Improvements in Switch Apparatus for Use in Distributing Electricity for Telephonic, Telegraphic, and other Purposes.
Year: 1895

page_text: Date of Application, 17th June, 1895
Complete Specification Left, 17th Mar., 1896-Accepted, 17th June, 1896
IONAL DIECIFICATION.
Improvements in Switch Apparatus for Use in Distributing
Electricity for Telephonic, Telegraphic, and other Purposes.
I, ROBERT PIPPETTE, of 51, Upper Tulse Hill, London, S.W., do hereby
declare the nature of this invention to be as follows:-
:-
1. My invention relates to improvements in switches for electric currents of all
kinds and in the operation thereof. These switches may either be operated
directly by hand or electrically. Among their uses, they are applicable to
automatic electric exchange for any system of electric telegraphy, telephony,
telautography, signalling etc., for the purpose of telegraphy, signalling &c., and for
electric power and lighting.
2. In the description of this invention, I make special reference and application
of these improvements to the systems instruments and their modifications
substantially shown and described and operated as specified in Patents No. 16,768,
1892, and No. 11,294, 1893. I do not however confine these improvements solely
to such systems and instruments since they may be used for electric exchange in
general whether an exchange operator intervenes or not.
3. In the aforesaid Patents, I use the making and breaking of circuits, positive
and negative currents, and timers for the purpose of operating the switching
instruments. There are other properties and effects of electricity and timers
which may be utilised for the same purpose, the particular property and effect
chosen for use in any particular case varying with the nature and duration
of the current used after the connection is made, and in some cases with the
required duration of the aforesaid current. Therefore I may substitute or add any
of the improvements hereinafter described for the operation of the switches
instruments &c. described in the aforesaid Patents where it may be advantageous
to do so.
4. The object of my invention is to utilise the various properties and effects of
electricity and those of timers for the purpose of electric switching and signalling,
to simplify the manipulations and operations required in switching, to reduce the
apparatus necessary at all points connected, to reduce all parts to their simplest and
most efficient elements, to the end, that persons using my invention shall need no
special skill training or practice in the operation thereof.
5. For the transfer of energy from one point to another for the operation of
switching instruments the operation of parts of switching instruments and the
various signalling instruments at the different points, I make use of the properties
and effects of electricity as follows.
6. As shown in Figures 6 and 7 and others, I use the making and breaking of
circuits for the purpose of operating electro-magnets.
7. I use relays included in the circuits where it is required to reinforce the line
current or to work the instruments indirectly by local battery power.
8. As the operation of the instruments involves the making and breaking of
circuits with the consequent production of sparks at the contact surfaces tending to
destroy them, I reduce such effects as much as possible by the employment of
infusible and inoxidizable metals for the surfaces, the use of carbon contacts,
compound metal and carbon contacts wherein the spark is taken by the carbon,
long metal contacts for a similar reason and rubbing contacts. Sometimes I do
not break the circuits at all, but shunt the current into other conductors or short
circuit the working circuit.

page_text: One
9. For suppressing the spark, I employ condensers in the usual-manner to take
the excess current. For a similar purpose, I employ accumulators formed of strips
of lead or lead wire in sulphuric acid and water; their poles being connected
to the magnets in the same manner as the poles of condensers to take the excess
current and give it up again through the magnets until they are neutralized.
or more such cells may be joined in series as may be required. Sometimes it is
only necessary to employ a cell formed by two copper wires or plates dipping in
water, the wires being connected to the magnet in the same manner as the poles of
the above mentioned accumulators.
10. Where it is necessary that the circuit through a magnet such as M in Figure 13
should be completed until the armature ARM reaches the magnet M, the following
switch may be used. In Figure 1, SP and SP 2 are two springs fixed to the
insulating block IB and connected to the respective poles of the magnet circuit.
SP carries an insulating block IB 2 of the form shown of which the face F is
covered with a metal plate connected to the spring SP. SP 2 carries-a-metal-
-projection-P-only, connected to spring SP 2. Both springs tend to press towards
one another. PN is a pin attached to the armature of the magnet or other moving
part and oscillates between SP and SP 2 and striking them alternately.
In its normal position, PN touches SP and bends it up causing the spring SP 2
to follow and the projection P will touch the spring SP at F thus closing the
'circuit. On the current passing the armature of the magnet is attracted and
with it the pin PN will move until it touches the spring SP 2 and bends it down.
SP following, the projection P will be pulled away from F and suddenly escape
'and rest in the notch of the block 1B 2 and thus break the circuit. On the recoil
of the armature the same process will be repeated.
11. Formerly, the switchboard contacts of the exchange instruments have been
formed by metal bars gecured to the backing of the switchboard. I now also form
them of metal wires W, Figures 2 and 3 strained over the face of the switchboard
which may consist of an open framework with studs ST'at intervals, to which the
strained wires are fastened by staples screws or simply let into notches N, Figure 3.
The moving contact operated by the switching instrument is shown in Figure 4
and consists preferably of a central metal disc D with insulating projections or
cogs C to slip in between the contact wires W aforesaid. The disc D is axled in
a frame F and is operated and connected by the switchcord of the switching
instrument in the usual manner. Such wires may be placed radially and the
contact wheel rotated on an arm turning about a fixed centre.
12. I also use the passing of currents of different polarities, positive and negative,
through the circuits in order to operate polarized armatures.
13. It being at times difficult to cause the polarized needles and armatures to
retain their central position of rest between the poles of the electro magnets even
by the use of check springs, I use two or more polarized armatures about the same
electro magnet, so arranged that only one shall leave its stop at a time when
attracted by the magnet.
In Figure 5, PA and PA 2 are two polarized armatures turning about the
centres C and C 2 and normally kept against the stop screws SS and SS 2 by the
springs SP and SP 2 or equivalent device. A current in one or the other
direction will cause both armatures to be attracted and repelled one way or the
other by the poles of the magnet M. But while one will leave its stop and
perform its duty, the other will be the more strongly pressed against its stop.
a similar manner, I may use two such magnets in series or parallel each attracting
its own polarized armature.
ID
14. In former switching instruments as shown in Figure 1 of the Patent
No. 11,294, 1893, after the connections have been made, a magnet with a polarized
armature is left in the circuit of the joined lines to receive the resetting currents
which must be sent in different directions from either end or the subscribers'
stations.
I now arrange that the magnet aforesaid shall be put in a shunt to earth from
2

page_text: the joined linewires so that like currents from both ends of the joined linewires
will affect it alike, the leakage not being sufficient to interfere with the
signalling.
"
15. I also use another method of operating the magnets as shown in Figure 6.
The key K may transmit currents from the battery BY in either direction into a
circuit containing the two electro magnets M and M 2. Their cores are magnetised
by induction from neighbouring magnets or are permanent in themselves. The
recoil of the springs of the armatures ARM and ARM 2 will just overcome
the attraction of the magnets and normally keep them away from their poles. The
current in passing through each will strengthen one magnet causing it to attract
its armature and weaken the magnetism of the other so that its armature remains.
The reversal of the current by the key K will have just the contrary effect and
weaken the magnet first mentioned and strengthen the second. The armatures
when attracted will perform their prearranged duties. The two magnets may be
in parallel instead of in series as shown.
16. The armatures shown in Figure 6 may normally be attracted by and to the
cores of the magnets the effect of a current through them being to strengthen one
magnet and neutralize the magnetism of the other allowing the armature to leave
its poles and perform the prearranged duty.
17. I also use difference of current strength caused by varying the resistance or
varying the electro motive force, and also difference of direction of current as
follows.
In Figure 7, K is a key in circuit with the contact C, the resistance R,
battery BY, the electro magnet M. The armature ARM when not attracted will
rest against the stop S. SP is a spring which resists the movement of the
armature ARM when attracted a certain distance by the magnet.M.
The circuit may be normally opened or closed.
I now suppose that normally the key K is kept closed. A current passes
through the circuit sufficient to cause M to attract ARM to the spring SP where
its further progress is stayed. If key K is opened, the armature ARM falls back
against the stop S and may thus complete a local circuit if required, or perform
any other required duty. If key K is pressed down so as to come into contact
with C 2 thus short circuiting the resistance R, the current, in the circuit increases
and the armature ARM overcomes the pressure of the spring SP and is attracted
further towards the magnet M and performs any prearranged duty.
18. Similarly we may arrange that the key K shall be able to sweep across the
contacts of several resistances in series all of which may be normally in circuit.
For the magnet M, a solenoid with movable core is substituted which according to
the strength of the current regulated by the resistances in circuit will take up a
corresponding number of positions within the solenoid for the purposes required.
We may substitute for the solenoid several magnets similar to M. The
springs SP fitted to each are arranged to give way under the varying pressures of
the magnets caused by the varying resistances inserted in circuit.
19. In place of opening the circuit shown in Figure 7, the variation of the
currents may be obtained as follows.
To keep the armature ARM in its normal position a definite resistance R should
be put in circuit. To cause the armature ARM to recoil, the movement of the
key K would insert further resistances, that is, instead of opening the circuit and
inserting an infinite resistance; while to bring the armature into the third position
the resistance R is short circuited or lessened by the action of the key K
as before shown. Also by decreasing or increasing the number of cells in the
battery BY by means of a key similar to K, the same effects may be gained. Also
by increasing or reducing the electro motive force of the battery BY by inserting
less or more cells in the circuit in opposition to the battery BY. In this manner
the current in the circuit may be reduced to zero or reversed.
20. Further PA, Figure 7 is a polarized armature operated by the magnet M2,
capable of performing any assigned duty. It is operated by reversing the current

page_text: from the battery BY by a key similar to K, Figure 6, so that while the magnet M
operates its armature by difference of current strength, the magnet M2 will
operate its armature by difference in direction of current. One magnet M may be
fitted with both the armature operated by current strength as ARM and
another PA 2 operated by direction of current. The reversing of the current may
be brought about by opposing and overbalancing the electromotive force of the
battery BY. More than one key K, resistance R, magnets M 2, M, and battery BY
may be included in the same circuit.
Also for the purpose of switching and the like, I may use circuits worked from
both ends ou the single and double current duplex or quadruplex systems in order
to utilise the lines to their utmost capacity, whether such systems are formed on.
the principles of difference of current, difference-of-direction, difference of electro
motive-force, or leakage.
21. The resistances, such as I use in the before mentioned systems and elsewhere,
may be readily made out of slips of lead pencil with sliding clips on the same, and
if required with coarse and fine screw motions for the adjustment of the lengths
included in the circuits. According to the mode of manufacture, and the ingredients
of the pencils, pencils of almost any suitable resistance can be obtained for the
purpose.
22. I also make use of the static electricity generated by induction friction,
dynamically, and chemically as follows.
Figure 8 shows a key K, battery BY, P a fixed metal plane, P 2 a movable
metal plane connected to the other pole of the battery BY. P3 P3 P3 are
connected metal planes also connected to the key K and P4 P 4 connected
metal planes also connected to the battery BY and movable about the axis AL.
When the key K is depressed it allows the free electricity from the battery BY to
pass along the circuit to the plane P and by induction and attraction on the electricity
of the opposite sign from the other pole of the battery BY in the plane P 2 to draw
the latter and operate any mechanism or circuit connected to it and in a similar
manner to attract the planes P 4 P 4 in between the planes P 3, P 3, P 3, thus
turning the former on the axle AL and operating any mechanism connected thereto.
23. With regard to the thermo effects of the electric current, I may mention the
passing of a current through a conductor, heating it, causing it to expand and
operate any mechanism connected, and on the cessation of the current, the
contraction by cooling may be used for any mechanical purpose. Such conductor
may be a wire, spring, or strip of metal.
24. The chemical effects of electricity may be used by causing a current to pass
'through a liquid decomposing it. If a gas result, this may be used to displace the
liquid in a bell and raise it by buoyancy and operate any connected mechanism.
If a metal or solid result, this may be deposited on a conductor and by the added
weight draw it down and operate any connected mechanism.
25. By the combination of the various properties herein before mentioned and
also by the use of timers in conjunction, I inay procure almost any number of
different effects which may be used as desired in the operation of these systems of
electric switching and signalling.
26. For the purpose of this invention, I use timers as shown and described in
Patents No. 16,768, 1892 and No. 11,294, 1893 as follows.
In Figure 9, the key K when depressed will close a circuit containing the
battery BY and the electro magnet M causing it to attract the armature ARM
when the latter will draw the hook H forward in opposition to the spring SP. On
breaking the circuit, the spring SP draws back the hook H and operates the
timer T, so that if the circuit remains open long enough after each contact of the
key K, the timer T or hook H will effect the operation desired.
27. As a timer, I may use any of the forms shown and described in Patents
No. 16,768, 1892, and No. 11,294, 1893, which may vary according to the desired
length of the period, from the inertia of some moving part of the apparatus such
as an armature and the like, a pendulum, bellows, dash pot, and the like to a train

page_text: of wheels regulated by a pendulum, fan, or bellows, whose movement may still
more be retarded by dipping or immersing them in liquids and the like.
In
28. A timer may also be operated only when the key K is depressed.
Figure 10, the key K, when depressed, will close a circuit containing the battery BY
and the electro magnet M causing it to attract the armature ARM. The latter
in its normal position presses back the spring SP to which is attached the hook H.
Therefore when ARM is attracted, the spring is released and the hook H operates
the timer T, so that if the circuit be closed long enough, the timer will effect the
operation desired.
29. Similarly in Figure 11, the armature ARM when attracted will pull and bend
spring SP attached to the toothed wheel TW and bring into operation the timer T
which will allow the wheel TW to turn at a given speed, and if the circuit be
kept closed long enough, the arm AM will then effect the operation desired.
30. Similarly the recoil of the armature ARM in Figure 12 may be used to
raise a detent D from the toothed wheel TW. When the armature ARM is
attracted, the detent D touches the wheel TW and completes a circuit containing
an electro magnet operating the hook H, which by a step by step movement rotates the
wheel TW in opposition to the spring SP or releases a mechanism which shall
rotate the wheel TW. Thus if the armature ARM be attracted long enough, the
wheel TW will be rotated far enough to effect the operation desired. The recoil
of the armature ARM will raise the detent D and release the wheel TW.
31. The armature ARM may also operate two timers, one to come into action
during the time it is attracted and the other after it has recoiled. In a similar
manner, it may be arranged that the armature when attracted shall slowly store
energy in a spring from which it will be released on the recoil of the armature and may
be applied to working another or the same timer if desired thus doubling the length
of the period.
a
At this point, it may be said in reference to the use of timers which effect a
certain operation after the circuit is closed for a certain interval of time,
that the signalling currents should be shorter in duration than the period of the
timer.
32. I also use the speeds at which the currents are sent for the purpose of
operating timers. In Figure 13, K, BY, M, and ARM are used for the same
parts as shown in Figure 12. When the armature ARM is attracted by the
magnet M, the hook H will engage with the first of the hooks of the multiple
hook H 2, drawing forward the spring SP. If the circuit is broken, the recoil of
the spring SP will by the hook H 3 operate the timer T at a certain speed. If the
armature ARM be again attracted before the timer has gone a certain distance
and allowed the hook H 2 to retire far enough, the hook H will engage with the
second hook of the hook H 2 and thus draw the spring SP forward a greater
distance and cause it to perform some prearranged duty and so on.
Thus I may
arrange as many hooks as I like on the multiple hook H 2.
If in the present.
instance the armature ARM be attracted after the timer has gone a certain distance,
the first stroke only will be repeated and no further action takes place. Thus for the
purpose shown, when the interval between the attractions of the armature ARM
is shorter than a fixed interval, the spring SP will perform its assigned duty, but if
the interval exceed the limit, the spring SP will only be drawn forward a certain
given distance and then recoil.
For the purpose of sending two or more currents in quick succession with one
depression of the key, a special key is used which in its descent sweeps over two
or more contacts.
33. By using this device, two or more effects may be obtained from a magnet
without change in the direction of the current as will be shown hereafter.
For instance, if currents with relatively long intervals between them be used
for signalling, groups of currents with relatively short intervals between them may
be used as shown to operate the switching apparatus.
34. A timer may also be used to act for a definite time after the first switching

page_text: current of each group, after which time the changes required take place, but this
labours under the disadvantage that the interval of time between the groups of
currents will vary and the person using the instrument will be uncertain when to
begin the next group of currents. This may be got over by using a telltale timer
at the point of similar period which shall inform the operator when the period of
the exchange timer is ended.
35. I also use timers to regulate the making and breaking of circuits in connection
with electro magnets on the instruments as follows.
In Figure 14, M represents the magnet in circuit with the key K, battery BY
the armature ARM and spring contact C. When the key K is closed, the
magnet M will attract its armature ARM, but the hook H will rotate the toothed
wheel TW or move any other mechanism required, break the circuit at the
contact C and engage the_hook H.2-with-the-timer T, so that before the
armature ARM can again recoil and make contact at C, it will have to operate
the timer T which may be set to any required speed. This comes in especially
where the key used for switching may be kept down all the time until the apparatus
shown in Figure 14 has completed the number of breaks in the line circuit
corresponding to the number required, such breaks being noted by any kind of
signal actuated by an electro magnet in circuit near the key.
36. Where the period of a timer is longer than can be conveniently measured by
such a timer as shown at T Figure 10, I sometimes use an arrangement similar to
that shown in Figure 14 where the armature ARM causes the hook H to operate
the toothed wheel TW, which carries a pin or projecting contact or by a simple
device completes the magnet M circuit until the toothed wheel TW shall make
part or a complete revolution by a series of impulses from the hook H, each
separated by an interval measured by the timer T.
37. The timers used in this invention are sometimes locked or stopped. if in
motion by the following arrangements.
In Figure 15, the armature ARM, when attracted by the magnet M, draws with
it the spring SP and when the spring SP recoils the hook H attached to it
operates the timer T. The timer may be locked on the descent of either the
armature ARM or spring SP by an arm or other projection from either of the
latter touching the wheel or pendulum or as shown, the timer T may be locked
until the armature has recoiled to its normal position in the following manner.
The armature ARM in its normal position raises the detent D from the
toothed wheel TW of the timer T and frees it, but if attracted the armature
allows the detent D to fall on the wheel TW of the timer and locks it. until the
armature resumes its normal position.
38. In the same manner one timer may lock and release another by the recoil of
the first timer raising a deteut from the second.
39. I have before mentioned the use of the duplex and quadruplex systems of
increasing the capacity of a line. In Figure 16 is shown a multiplex system for
the same purpose.
Figure 16 shows three stations A, B, C connected by one linewire L. The
instruments at stations B and C are similar to that at A now to be described.
The distributor at station A contains two series of circuit segments numbered
from 1 to 12. Numbers 1 and 2 and 11 and 12 only shown. CS is the correcting
segment. An enlargement of segment CS is shown in Figure 17.
It consists
of two plates E and F so shaped and situated that the correcting trailer CT when
passing will be in contact with both for a little distance. An arc of 60° includes
the first circuit segment and the correcting segment, therefore the trailers will be
60° apart as shown, and as one leaves the correcting segment, the next will touch
the first circuit segment.
After passing the correcting segment each trailer
drops and will touch nothing until it arrives at the slope SL which raises it to
the level of the segments.
A portion of the slope SL may be covered with
velvet to clean the trailer contacts. There may be of course one trailer only and
the series of circuit segments repeated all round the track of the trailer.

page_text: 40. Synchronism is thus secured.
One trailer CT or more as required, called the correcting trailer, touches the
segments at a point farther from the axis than the rest, so that in its passage it
will touch the correcting segment which the other trailers miss. The arın of the
trailer CT is also lengthened.
The path of the trailer CT is barred by the spring SP. If the correction of the
instrument require it, the trailer CT will touch the spring SP and be retarded
by it more and more until the spring SP touches the screw S, when the trailer CT
would be stopped altogether. In practice. this would not often occur as the
spring SP would be taken out of the path of the trailer CT before any stoppage.
took place. When the trailer CT touches the spring SP a local circuit including
the battery BY 2 and the magnet M 2 is closed. The office of M 2 is to retard
the phonic wheel or other mechanism driving the trailer. When the trailer CT is
in contact with the plates E and F of the segment CS and the spring SP touches
the contact screw S 2, another local circuit will be closed including the battery BY 2
magnet M 3 and the contacts between the screw $2 and the armature of the
magnet M carrying the spring SP so that the circuit can only really be closed
when the magnet M attracts its armature and the trailer CT joins the segments E
and F. The office of M 3 is to accelerate the phonic wheel.
41. When the trailer CT is in contact with the plate F of the segment CS,.
the linewire L on the right of the station is connected to the magnet M and a
branch of the linewire on the left of the station including the battery BY. A
similar battery may be used with advantage in a similar position at the other
stations but only one is really necessary.
42. The office of the magnet M is to lift the spring SP out of the path of the
trailer CT and to make contact between the armature and the screw S 2. The
connections of arm No. 6 with the instruments for sending and receiving are shown..
No condensers are shown.
I suggest that the connection between the phonic wheel and the trailers
should be a frictional one, as if the trailers were stopped, the wheel would not be
brought to rest.
43. If battery BY be taken out of the circuit, the trailers CT at all stations.
would be stopped by the springs SP. On inspection, a circuit will be seen to be
completed at each station from line wire to linewire through the trailer CT, the
plate F of the segment CS and the magnet M. Now switch in the battery BY,
and all the magnets M will be operated, the springs SP be raised and the
trailers CT released. In practice, one phonic wheel will now and again lag behind
the others and the trailer CT will be late in arriving at the segment CS, then the
circuit through the magnets M will remain open until the late trailer touches
the segment CS when the circuit will be completed and the springs SP raised as
before.
44. I will now show how the slow wheels are accelerated and the fast wheels.
retarded.
For instance, if the trailer CT of station A arrive at the contact F of the-
segment CS while the others are touching segments E and F, the circuit will be
completed the armatures of magnets M at stations B and C will be attracted, the
springs SP will be raised and the local circuits through the magnets M 3 closed
and the trailers CT accelerated.
If at the moment the circuit is formed through the magnets M, the trailers CT
have advanced so that they are clear of the plate E and only touch the plate F the-
springs SP will alone be raised.
If before the circuit is formed through the magnets M, the trailers CT have
touched the springs SP, they will be mechanically retarded by compressing the
springs and the circuit through M2 being closed the phonic wheels will be
retarded. Thus it will happen, that one or other of the trailers CT will be
accelerated or retarded, so we may assume that they cannot vary very much either
way. It is however a good plan to allow one station such as A to set the rate for

page_text: the other trailers in which case the magnets M2 and M.3. may be omitted. By
allowing the spring SP a little more freedom, there is formed a neutral ground
between the points when the accelerating magnet is operated and the operation of
the retarding magnet.
The instruments connected as shown at arm 6 may be worked by positive
currents and the correction effected by negative currents from the battery BY
acting on a polarized relay at each station sensitive only to such negative
currents.
.
45. In a modification, the phonic wheel or other motor may be omitted and the
apparatus arranged at each station so that a current from the battery BY will
cause the magnets M to operate their armatures and store up sufficient energy in a
spring to carry the trailer of each station round one revolution, the regulation
being applied by a pendulum or fan or other timer, the correction being attained
by the magnets M 2 and M 3 regulating the depth to which the pendulum or fan
dips in a bath of mercury or other liquid.
46. As before-shown,-f-transmit the motion of the armatures of magnets or other
moving parts for the purpose of rotating wheels or moving other parts by means
of hooks or pallets, and I also use propelments clutches or any escapement such as
the anchor capable of transmitting any motion received by them to a wheel or
similar device.
47. The electro magnets used have often to apply a force over a long distance.
As it is economical to keep the armature of an electro magnet in the strongest part
of the field, I adopt the usual device of applying the power of a magnet to a lever
at a point nearer the centre or fulcrum about which it acts and take off the power
from the lever at a point situated at a greater distance from the centre as may be
required.
48. I also employ the following device for the same purpose. In Figure 18 is
shown a magnet M whose office is to operate some device which shall in turn operate
some further device. In this case, the magnet M operates the hook H which in
turu will operate the multiple hook H 2.
On depressing the key K, the magnet M attracts its armature ARM and draws
down the hook H 2 a distance of one tooth and then breaks the circuit or short
circuits the magnet M by a device similar to an electric bell break or a break
described and shown in Figure 1 or a slide contact. By the impulse of a recoil
spring, the armature returns to its normal position and again closes the circuit or
opens the short circuit of the magnet M when the armature is again attracted as
before and so on, until the hook H 2 is stopped or the circuit is broken at the
key K. As the movement of the armature ARM may be in the strongest part of
the field of the magnet M, it may be acted upon with great power over a short
distance and move very rapidly, so that its effect is that of a long pull while it
takes place in a very short period of time.
49. Another device for the same purpose is shown in Figure 19. It is required
to draw the lever LV or similar device downwards. To LV is attached the rod R
carrying the armatures ARM and ARM 2 of the magnets M and M 2. The
armatures may slide on the rod R above but their descent is prevented by the
collars CL and CL 2 upon which they normally rest.
The lever LV is connected
to one pole of a battery and carries a contact C which can sweep over the
contacts C1 and C2 respectively connected to the magnets M and M 2, the other
ends of the magnet coils being connected as required to the pole of the battery
through the wire W.
Contact C is normally in connection with contact C 1 thus bringing the maguet M
into circuit. Upon closing the circuit of the battery by a key or other device,
the magnet M is operated and causes it to attract its armature ARM to it and by the
pressure of the armature on the collar CL will draw down the rod R and lever LV.
The contact C also moves and when the armature ARM rests on the poles of M,
contact C breaks contact with contact C1 of magnet M and sends the current
through the magnet M 2 which in turn attracts its armature ARM 2 drawing down

page_text: the lever LV still further while the armature ARM of magnet M is left on
the poles of magnet M. In this manner three or more magnets may be utilized.
50. In a modification of the above, the rod R may be rigidly fixed to the lever LV
and curved about the centre about which LV turns and the magnets M and M 2
would be arranged in the same locus to act on the armatures ARM and ARM 2.
51. In Figure 20 is shown a hook H employed to rotate the toothed wheel TW.
When H is operated by the armature ARM of an electro magnet or by another
moving part, the action takes place so suddenly that it is of the nature of a blow
and the tendency is to jerk the wheel TW round farther than is necessary.
I neutralize this by increasing the tension of the recoil spring SP if used, or by
increasing the pressure of the detent or rachet DT, or by increasing the pressure
of the hook H on the wheel TW when it touches it.
52. I also increase the pressure of the hook H on the wheel TW as follows.
Normally the shaped projection P from the hook arm bears against the pin PN
and H is kept away from the wheel TW. The book arm being movably connected
to the armature ARM is kept pressed towards the wheel TW by a spring SP 2
and it thus happens that when the hook is operated it touches the wheel TW in
accordance with the form or shape of the projection P bearing on the pin PN and
comes into contact and presses on the wheel TW as may be desired.
53. also increase the pressure of the hook H on the wheel TW by fixing as
may be convenient arms or projections from the hook arm H, which as it moves
shall come into contact with fixed guides or pins and force it against the wheel TW
such as the projection P2 against the pin PN 2, or the projection P 3 against the
pin PN 3, or the projection P 4 against the pin PN 4.
54. I also arrange for the same purpose of preventing unnecessary movement of
the toothed wheel TW, that the hook arm when operated shall cause a friction
brake to bear more or less on the wheel TW, or the hook arm itself may carry a
curved damper formed of leather or velvet which shall embrace the wheel preventing
any movement after the hook comes to rest.
55. In order to be more certain as to the distance the toothed wheel T W moves,
I sometimes use the following arrangement shown in Figure 21.
The hook H when operated will engage with the toothed wheel TW fixed to the
axle AL. On the same axle is another toothed wheel TW 2 in which the
detent DT may engage. DT is movably connected to the recoil spring SP which
plays between the adjustable stops or screws SC and SC 2. Normally the hook H
raises the detent DT from the wheel TW 2, but when operated it allows the detent
to fall on the wheel TW 2 and this by engaging in its teeth confines the movement
of the wheel TW 2 and through it the motion of the wheel TW and the operation
of the hook H within certain limits as set by the screws SC and SC 2. When the
hook H rises, it raises the detent DT which latter springs back into its normal position.
If the wheel TW 2 be set to move on the axle AL within certain limits in
relation to the wheel TW, the spring and set screws SC and SC 2 may be
dispensed with.
56. may also cause an armature to move relatively slowly by making it in its
descent to operate a timer of short period formed by clockwork, liquid or gaseous
friction, such as a dashpot or bellows, or the hook may be operated by the recoil
spring instead of directly by the action of the magnet's armature.
57. In Patents No. 16,768, 1892 and No. 11294, 1893, the switching and ringing
currents sent by the calling subscriber are in one direction while the resetting
current is in the reverse direction. As pointed out in paragraph 92 of the Patent'
No. 11,294 1893, the subscriber called, B, has to ring up the calling subscriber A
by sending his resetting current. This is a complication to be avoided if possible.
I therefore arrange that the ringing current ou reaching the station called shall
traverse a magnet acting on a polarized armature in such a way that the battery
connections are reversed by mercury or other switches so that ringing and
switching from either end are performed without shifting the battery connections
by hand. When the station called, B, wishes to ring off, the resetting key is
B

page_text: touched and the passage of the current through the aforesaid -magnet will change
the poles of the battery again and the station will be operated as usual.
The changing of the battery poles may also be performed by the subscriber
called, B, by hand with any suitable switch for the purpose.
I have mentioned that these switches should change or reverse the battery but
the same result will be obtained by changing the connections of the subscriber's
station with respect to the line and the earth.
58. I will now show the adoption of this system of switching to the ordinary
multiple switchboards used in telephony wherein the connections are made by
means of switchcords, pegs, spring jacks, and the like. The place of the operator
is taken by the switching apparatus, and the subscribers themselves operate the
switch by sending one or more groups of currents of electricity.
59. The principle of the electrical parts of the switching apparatus is similar to
that shown in Figure 198 of Patent No. 11,294, 1893. The switchcords pegs and
spring jacks may be of any convenient and suitable pattern without-interfering
with the operation-of-the-switch. The relative positions shown are those to be
recommended.
60. In the usual manner, the multiple switch, if large enough, is divided into
two or more separate similar sections each containing spring jacks representing all
the subscribers on the exchange. Each section is fitted with a switching apparatus
now to be described, and also with the switchcords of a certain number of
subscribers, each of whom may use the switching apparatus of this particular
section for inserting his switch peg into any spring jack.
61. In Figure 22, SK represents one such section of the multiple switchboard.
Some of the spring jacks are represented by the dots J, J. These are arranged in
panels in regular horizontal and vertical rows.
For the purpose of description, I will suppose that the numbers of the subscribers
on the exchange run up to four figures or digits, and that any one subscriber A
wishes to switch on to or insert his switch peg into the spring jack of any other
subscriber, B, whose number contains four digits.
62. Every subscriber including A and B, is supplied with an ordinary telephonic
equipment as shown at A Figure 23, wherein E is the earth or return wire con-
nection. M, a magneto, T, a telephone receiver and transmitter, BL, the bell,
1, 2, 3, 4 and 5, switch contacts. Normally 2 touches 3, when ringing 2 auto-
matically touches 1, when speaking 3 touches 4. The key 7 is normally in contact
with 5. The exact detail of the telephonic equipment is not of great moment, but
each station should possess a source of electricity such as the battery BY whence
a current of electricity may be sunt to the exchange for operating the switch.
The battery BY is connected to earth and the contact 6. When the key 7 is
depressed, it will leave contact 5 and touch contact 6 allowing a current to pass to
line L. As it is necessary to send a current in the reverse direction to the switching
currents for resetting the instrument, 1 use the magneto, which is turned in the
contrary direction to that when ringing through. Otherwise we should use a
reverse current from the battery BY in which case the key 7 would be a pole
changing switch of some kind.
63. Referring to any one subscriber, for instance A, subscriber A is connected
to the exchange by one linewire L, which after traversing the electro magnet PM,
Figure 23, terminates in the spring contact S 8. The spring S 9 is connected to
earth. The spring S 10 is connected to the switchpeg SP by means of the switch-
cord SC. Spring S 11 is connected to the spring jacks of the subscriber. The
spring S and contact screw S2 form part of the circuit including the switching
magnet SM Figure 22, the local battery, the armature PA, Figure 23 and the
contact screw S3. Normally spring S8 is in contact with springs S9 and S 11
and the spring S touches the contact screw S 2.
64. Subscriber A first sends to the exchange by depressing the key 7, a group
of switching currents corresponding to the first digit of the number of subscriber B.
These pass through the relay magnet PM, the springs S8 and S 9 to earth. The

page_text: magnet PM deflects the polarized armature PA which touches the screw S 3 and
closes the circuit of the switching magnet SM and the local battery. The
magnet SM operates its armature ARM carrying the moving hook MH. The
position of MH is controlled by the timer T the latter being operated by the same
magnet SM.
The deflection of the armature PA pushes the rod RD carried by the rod RD 2
centred at the point CE and connected to the hook HK forward in such a manner
that the hook HK comes in the path described by the rod RD 3 when turned
about the axis of and by the rod RD 4. The operation of the magnet SM
attracting its armature ARM with its moving hook MH draws down the lever LV
turning the rod RD 4 and with it the rod RD 3 about the centre of rod RD 4
and pulls down any hook HK which may be in the path of RD3. Thus the
hook HK of subscriber A is pulled down, and with it the stop ST attached to
the hook HK descends through the hole H in the shelf SH. For the time being
the rod RD 4 is kept in its lower position by the hook HK 2 against the pressure
of a spring which tends to replace it in its normal position.
65. The hook HK is attached to the lever LV 2 turning about the centre CE 2.
The lever LV 2 is moved by the hook HK and its other end rises moving the
lever LV 3 turning about the centre CE 3 in such a manner that the spring SP
carrying two hooks HK 3 and HK 4 is raised above the ends of the springs S
and S 8 while the other end of the lever LV 3 descends and almost rests on the
rod RD 3 when the latter is in its normal position.
66. While the hook MH is operating the lever LV it also operates the
lever LV 4 turning a rod RD 5 carrying the rod RD 6 not shown but similar
to the rod RD 3. The rod KD 6 simultaneously raises the hook HK 5 and releases.
the carriage CG which up to the present time has been detained in its normal
position by the hook HK 5.
The carriage CG is a frame carried on the rail RL by the two grooved
wheels W and W 2. The side of the rail RL is cut as a rack RK. A toothed
wheel TW engages in the rack RK. The wheel TW is connected by the
rod RD 7 to a similar toothed wheel TW 2 gearing in a similar rack RK 2 on
the rail RL 2. These wheels TW and TW 2 preserve the parallelism of the
carriages CG and CG 2, which are rigidly connected by the rods RD 8 and RD 9.
The carriage CG 2 is kept vertical by the grooved wheels W 3 and W 4 which
are guided by but do not necessarily rest on the rail RL 2.
67. After the release of the carriage CG from the hook HK 5, the whole
system moves to the left under the impulse of the falling weight WT transmitted
by the cord CD over the wheel W 5 until the carriage meets the stop ST, which
slips into a slot in a spring striking plate in such a manner as to prevent any
motion of the carriage CG either to the right or left.
68. The movement of the rod RD 6 touches a lever on the carriage CG causing
the rod RD 10 to move to and fro on its axis. The rod RD 10 is studded with
pins at intervals on the first of which the stop ST 2 normally rests. The
rod RD 10 passes through the central part of the stop ST 2 where two sloping
pallets are fixed. The stop ST 2 can likewise move up and down on the rods RD8
and RD 9 to which it is attached by the collars CL and CL 2. Every motion
of the rod RD 10 allows the stop ST2 to fall on the next pin, every to and fro
movement allowing it to fall vertically a distance of ten spring jacks until the
required ten is reached. Any backward movement of the stop ST 2 is prevented
by a detent hook carried by it catching in the teeth of a rack cut on one of the
rods RD 8 or RD 9.
Thus the first group of switching currents has depressed the stop ST, brought
the carriage CG to the stop ST and caused the stop ST 2 to descend to the required
division of spring jacks.
The timer T now comes into operation and shifts the hook MH into the second
position.
69. The second group of switching are sent in the same manner and through

page_text: the same conductors as the first group, again operating the magnet SM which
again operates the timer T and by the hook MA moves the lever LV 5 thus
turning the rod RD 5 in the reverse direction to the last. The movement of the
rod RD 6 causes the escapement ES on the carriage to vibrate releasing tooth by
tooth the wheel TW 3 gearing in with the rack RK 3 and allow it to descend by
the weight of the rod RD 10. The rod RD 10 is held by the rack RK 3 and
partakes of its motion so that the stop ST 2 is lowered until it arrives at the
required line of spring jacks.
70. The second group of switching currents finished, the timer T comes into
operation and transfers the hook MH into its third position. The third group of
switching currents is sent in the same manner and through the same conductors as
the second group operating the magnet SM which again operates the timer T and
by the hook MH operates the lever-L-V-6-and-through-it the rod RD 11 axially
RD 11 is similar in all respects to the rod RD 10 and controls the movement of the
stop ST 3 similar to the stop ST 2, and which slides along the guide rods RD 12
and RD 13 to the left under the impulse of the falling weight WT 2 transmitted
by the cord CD 2. Any backward motion of the stop ST 3 is prevented by a
detent on the stop engaging in a rack cut on one of the rods RD 12 and RD 13.
71. Simultaneously the hook MH pulls down the spring SP 2 carrying the drum DR
fitted with a toothed wheel to gear with the toothed wheel TW 4. According to
circumstances, the wheel TW 4 may be set in motion by the pulling down of the
spring SP 2 or always be kept in motion. In either case, the drum DR partakes of
the motion of the wheel TW 4 and begins to wind up the cord CD 3 upon it. The
spring SP2 is kept down by the hook HK 6 fitted to the armature ARM 2 of the
magnet M 2. The cord CD3 is fastened to and passes several times round the drum DR2
on the carriage CG to a drum on the axle of the toothed wheel TW 5 on the slide SL.
After passing once or twice round the latter drum to which it is also fastened it
terminates in the weight WT 3. The drum DR 2 is provided with a toothed
wheel on the same axle in which a detent usually engages so as to prevent it
turning in the direction of the drum DR, but at the present moment the
drum DR 2 is free as the detent above mentioned is forced away from the toothed
wheel by the stop ST.
72. The slide SL is a frame capable of moving vertically on the guide rods RD 8
and RD 9, to which it is attached by the collars CL 3 CL4 CL 5 and CL 6. By
the pull of the cord CD 3, the slide is pulled up in such a manner that the cup or
clip CP moves upwards and passing over the nose N of the switch peg SP shown
in Figure 23 and also in Figure 24, until it reaches its highest point when a pro-
jection from the interior of the clip slips over the recess R of the switch peg and
holds it against all backward pull due to the weight WT 4. Directly this happens
the circuit of the magnet M 2 and a local battery is closed and M 2 attracts its
armature ARM 2 releasing the wheel and drum DR from the wheel TW 4. At
the same time, the hook detent D centred at CE 4 which has hitherto held the
slide moves to one side and then the slide SL is free to descend taking with it the
switchpeg SP and the cord SC until it is stopped by striking the stop ST 2 to
which it is now connected by the hook HK 7 slipping over the pin P.
At the end of the third series of switching currents we have the switch peg
lowered to the level of the row of spring jacks in which subscriber B's spring jack
is to be found.
73. The timer T now comes into operation and transfers the hook MH to the
fourth position. The fourth group of switching currents is sent in the same
manner and through the same conductors as the third group again operating the
magnet SM, which again operates the timer T, and now by the hook MH operates
the hook HK 2 thus releasing the rod RD3 which springs back into its normal
position and allows the stop ST to rise, when the carriage CG under the force of
the weight WI travels to the left until stopped by the piu P2 which also raises
the lever LV 7 turning with some friction on the centre CE 5 sufficiently to
strike the stop ST 3 when the carriage CG travels to the right. The detent of

page_text: the drum DR 2 can now engage with it and prevent any motion when pulled by
the cord CD 3.
At the same time, the hook MH operates the escapement ES 2 similar to the
escapement ES in such a manner as to allow the toothed wheel TW 6 to move
the rack RK 4 gearing in with it to the left carrying the rod RD 11 and the
stop ST 3 with it.
74. The fourth group of switching currents ended, the timer T comes into
operation and transfers the hook MH into the fifth position completing the circuit
of the magnet SM automatically, when the hook MH is again operated and pulls
down the druin DR upon the wheel TW 4 to which it is held by the hook HK 6.
As a result, the cord CD 3 is wound up on the drum DR and the carriage CG is
brought back to the right until it strikes the stop ST 3 which lifts the rachet or
detent off the toothed wheel of the drum DR 2, when the cord CD3 begins to
turn the drum of the toothed wheel TW 5 in opposition to the weight WT 3.
75. The wheel TW 5 gears in with the rack RK 5 Figure 23 carried on the
rail RL 4 by the toothed wheel TW 7 and the wheel W 6. The rack RK 5 is also
kept in position by the contact of the wheels TW 7 and W 6 with the rail RL4,
the left hand portion of which is cut as a rack RK 6. The motion of the
wheel TW 5 tends to move the rack RK 5 forward towards the switchboard
carrying with it the cup CP, which is centred on the wheel TW 7. When the
wheel TW 7 reaches the rack RK 6 it gears into it and passing along turns the
cup CP up for 90° so that the nose N of the switchpeg SP is pointing directly to
the spring jack required. The wheel TW 7 now reaches the end of the rack RK 6
and is kept in position by the hook HK 8 detaining the pin P 3 but the wheel TW 5
continues to turn and forces the switchpeg into the spring jack of subscriber B
where it is retained as will be shown. The circuit of the magnet M 2 is completed
by the rack RK 5 and releases the drum DR from the wheel TW 4 when the
weight WT 3 asserts itself and turns the wheel TW 5 in the opposite direction
retracting the rack RK 5 and with it the cup CP, the halves of which are rather
feebly held together by a spring and passes easily over the back of the switch peg,
the hook HK 8 is removed from and releases the pin P 3 and the cup falling, the
rack RK5 reaches its normal position.
76. On the slackening of the cord CD 3, the deteut of the drum DR 2 which
was raised by the stop ST 3 falls into gear with the toothed wheel of the drum DR 2.
and prevents any motion of the drumm DR 2 when pulled by the cord CD 3. The
hook MH at the same time turns the rod RD4 on its axis by operating the
lever LV 8 when the rod RD 3 raises the end of the lever LV 3 and brings down
the spring hooks HK3 and HK 4 until the springs S and S8 are caught by the
detent hooks HK 9 and HK 10. This opens the magnet SM circuit by separating
the springs S and the screw S2. It also puts the line L into circuit with the
switch ord and peg by contacting springs S8 and S 10 and earths the spring jacks
of A by contacting springs S9 and S 11.
77. I will now explain the essential parts of the switchpeg SP. The switch-
cord SC after passing through the hole H in the shelf SH and before reaching the
switchpeg, passes through the ring R attached to the arm AM centred at CE 6.
By the pressure of a spring it tends to turn towards the face of the switchboard
in such a manner,
that after the switch peg is drawn out by the cup CP, the cord
is pulled towards the switchboard out of the way of succeeding switchcords as
shown by the dotted lines.
78. Whatever may be the system of multiple switchboard employed, the switch-
peg first consists of a metal thimble TH, inside which the switchcord SC is
fastened, and the other connections made. The body of the peg consists of a
hollow electro magnet EM whose function is to attract the detent D 2 which forms
its armature.
'
When the peg is pushed home into the spring jack by the cup CP, the
detent D2 catches in the face ring of the jack and thus holds the peg in the
spring jack.

page_text: Sometimes, for a purpose to be presently mentioned, the spring SP is fitted, and
when the peg is pressed home the spring is compressed. If the detent D be
attracted by the electro magnet EM, the spring SP will expel the peg from the
spring jack.
.
79. The electro magnet EM is in circuit with the armature PA, the contact
screw S4, and the magnet M 3 not shown of which the armature will operate the
lever LV 7 and a local battery. The magnet PM has a supplementary winding,
normally in circuit with a local testing battery, the thimble TH and nose N, but
when the hooks HK 3 and HK 4 are operated, a spring contact is moved which
transfers the circuit of the thimble and nose alone to the other pole of the afore-
said testing battery.
The spring jacks of each subscriber are fitted with a testing wire passing to each
spring jack. The nose of any switchpeg-will-come-into-contact with this test wire
when in the spring jack, therefore the nose of A's switchpeg is now in contact
with B's test wire thus placing it in connection with the testing battery
aforesaid.
80. Now the switchpeg is in the spring jack, a ringing current passing from
A's line through the magnet PM and B's magnet PM will deflect B's armature PA,
and by a mercury switch cut off his earth connection and so the ringing current
can pass to B's station. Conversation takes place as usual.
Directly after the peg has been pushed home in the spring jack of B, the circuit
of the magnet SM is closed by the return of the rack RK and the latter draws
the drum DR into connection with the wheel TW 4 when the cord CD 3 is again
wound upon the drum DR and drags the carriage CG with the stop ST 3 back to
the starting point, a projecting pin at the starting point pushes aside the detent
preventing the rotation of the drum DR 2 and a projecting vertical rod pushes
aside the detent keeping the slide SL in its assumed position and allows it to be
pulled upwards until it reaches the top, when the stop ST 2 is released from the
slide SL by the lever of the hook HK 7 striking a portion of the carriage CG,
and falls back on the first stud of the rod RD 10, and sets the hook of the detent D
to catch the slide SL by the pin P 4. The slide SL completes the circuit of the
magnet M 2 and releases the drum DR, and the slide SL being free falls back
on the detent D. The hook HK 5 as before shown keeps the carriage in its normal
position. At the same time the hook MH is replaced in its normal position and
the switch is ready for another call.
81. Ou the finish of the conversation, one or the other subscriber sends the
resetting current which is in the reverse direction to the switching currents and the
armature PA is deflected in the opposite direction contacting the screw S4 and
completing the circuit of a battery and the magnets M 3 and EM. The armature
of M 3 by means of the lever LV 9 will turn the rod RD 14 about its axis and
thus cause the rod RD 15 to strike the book HK 11 which has been pushed out by
the movement of the arniature PA transmitted by the rod RD 16 hung from the
rod RD 17 centred at CE 7, and the lever will pull the books HK 3, HK 4, HK 9,
and HK 10 away from the contact springs and reset the instrument.
82. If another peg should be switched on to the same spring jack of subscriber B
occupied by A's switch peg, its nose N would strike the thimble TH of A's peg
and a current would pass through the suppler entary coil of the magnet PM of
the switching subscriber from the testing battery and by deflecting his armature PA
similarly reset the switch.
83. If a switch peg be inserted into one of B's spring jacks at another section
of the switchboard, the same effect takes place as A's spring jack's nose N touches
the testing wire which runs through all B's sp ng jacks and puts the testing wire
in connection with one side of the testing bati ry, so that the resetting circuit is
operated in a similar manner.
84. Where it is necessary to do so, the first switching current of any subscriber
will also disconnect the remainder of the subscribers belonging to that section by

page_text: an earth bar similar to the rod RD3 and connect the switching subscriber to earth.
through his own contact springs. At the termination of the switching operation
the earth is again restored.
85. In the following figures, I have only shown the systems applied to ringing.
bells at the different points but other telegraphic or telephonic instruments may be.
inserted and operated as may be convenient.
86. In Figure 25 is shown a system of connections of two or more points A, B,.
to the exchange EX. A separate speaking or ringing wire SW, SW 2, runs from
each point to the exchange EX and there terminates in a contact similar to C, C 2..
CW is a common speaking or ringing wire common to all points. SWW is a
switching wire common to all points in circuit with an electro magnet M and
the battery BY. RW is a common return wire or the earth passing through
each point. BW is a common battery wire passing through each point. If
batteries be used at each point and earth used as a return, the wires BW and RW
may be omitted.
87. If a point, for instance A, wishes to speak to another point B whose number
is for example No. 4, point A presses his key SK four times each time operating
the magnet M. The first current passing round the magnet M will attract the
armature ARM and by the hook H4 depress the spring SP3 and the timer
hook H 3 which engages with the timer toothed wheel and operates the timer T
and also draws away the detent D from the toothed wheel TW by means of the
hook H 2 operated by the arm AM hinged on the armature ARM thus releasing
the wheel TW if before operated and it returns to its starting point being drawn
back by the recoil spring SP.
88. As shown above, the first current has drawn down the timer hook H3 which
is now operating the timer T, we shall find that the lever LV hinged to the timer
spring SP 3 and embracing the hook arm AM is not now in contact with the
pin PN and thus the hook H is at liberty to move towards the wheel TW being.
pressed towards it by the spring SP 2 so that the next current passing round the
magnet M in operating its armature ARM will again depress the timer hook H 3.
and also pull the hook H down but the latter will engage with the toothed
wheel TW and rotate TW a distance of one tooth bringing the contact arm CA
into contact with the first contact C connected to the first point and so on for
next current until the required contact is reached. The wire CW is now
through the arm CA in contact with the required point's wire SW 2 through the
contact C 2.
89. When the timer has finished its period, the hook H3 rises with the
spring SP 3 and causes the lever LV to touch the pin PN and thus draw the.
hook H out of contact with the wheel TW and bring the hook H2 within
the range of the detent D, so that the first current of another set of switching
currents will operate the detent D and reset the wheel TW and contact CA as
above shown.
90. After having switched on to some given point, the calling point can ring up..
the given point by means of the key K2 which disconnects the bell B from.
contact 2 and transfers it to contact 1 of the key K 2 when it is to receive
signals. This key is a Morse key through which the ringing will take place as
usual.
91. The key K and key K 2 are compounded under one key as shown in
Figure 26. The key K 3 as shown is kept in the position shown by a spring and
is connected to the wire CW Figure 25. In the position shown in Figure 26, it
presses on the shaped spring forming contact 3 and puts it in contact with contact 2,.
key K 3 is however insulated from contact 3. If depressed in its present position
it will press the contact 4 into connection with the contact 5 thus sending a
switching current through the magnet M and operate the switch as before shown.
After the switching is finished the key K 3 is moved to the right and allows the
spring SP to rise and separating the contact 3 from contact 2 and then touches:
the upper portion of contact 3. When depressed, the key K 3 leaves the upper-

page_text: portion of contact 3 and touches the contact 6-thus sending a ringing current to
_the-common-line CW. It is however quite possible to use a separate bell to
receive instead of one bell for both purposes.
92. In a modification, the contact CA, Figure 25, when at zero or in its normal
position makes contact with the first point's line SW, so that one switching
current sent will reset the instrument and put the line CW in connection with the
first point.
93. In a modification of the system shown in Figure 25, one or more bells may
be introduced into the circuit formed by the switching wire SWW which may ring
when the switching current is sent. This is an audible signal of the point wanted
and is very useful in a house.
94. In
a modification of the system shown in Figure 25, the speaking
wires SW, SW 2 and the like may be connected to a separate system of bells
ringing in the exchange or at any other point or points with separate indicators
for each wire at the exchange and a common_return-wire-passing through each
_ point-and-a-key-at-each point which will when required separate the contacts 1
and 2 and join 2 to the return wire of the bell system for the time being when the
bell system has to be used.
95. In a modification of the system shown in Figure 25, the special battery
wire BW is omitted and the timer after the switching is finished cuts the magnet M
out of circuit so that the switching wire SW W for the time being becomes the battery
wire for ringing and the like, the timer being so arranged that it reintroduces the
magnet M after a certain number of seconds after the switching is finished or after
the last ringing current is sent.
96. In a modification of the system shown in Figure 25, the special switching
wire may be omitted, and the wire CW may be used for switching, the timer after
switching cutting off the switching magnet for a few seconds so that the wire CW
may be used as the ringing wire and the like.
97. In a modification of the system shown in Figure 25, the wires CW and SWW
are omitted the switching and speaking being carried on through the special
wires SW and SW 2 from each point, an electro magnet being inserted in each
circuit to connect the particular calling point's wire to the moving contact CA,
the timer disconnecting the switching circuit and resetting if required or the
resetting may be determined by some effect of the aforesaid magnet in the wire of
the calling point.
98. In a modification of the system shown in Figure 25, we may do away with
the common wire CW by arranging that the switching key of the switching point
for instance A shall connect the speaking wire SW to the battery wire while
switching for the following purpose.
The switch at the exchange is fitted with the locking arm similar to LA
Figure 28 which shall be released by the first switching current and allowed to
sweep over the contacts C and the like. The locking arm is in circuit with a
magnet and the battery BY in such a manner that when the locking arm touches
the contact of the switching point the timer will cut off the battery BY and the
magnet aforesaid and connect the locking arm to the contact arm CA so that
communication between the switching station and the called station will take place
through the locking arm and the moving contact arm CA.
99. In a modification of the system shown in Figure 25, each point may have a
separate instrument similar to that shown with separate switching and ringing
wires and a common return wire being used if required. Where the earth and
batteries are used at each point, the two latter wires may be dispensed with.
100. In a modification of the system shown in Figure 25, each switching
operation consists of at least two groups of currents through the switching wires,
the first will bring the arm similar to the contact arm CA to the fixed contact of
the signalling point, after which the timer will change the hook H to the mechanism
moving the contact arm CA and will as there shown move the latter to the fixed
contact of the point required. The former arm and the arm CA being connected,

page_text: communication between the two points may be effected. The first current of each
switching operation will reset the instrument as before shown.
101. In the system shown in Figure 27, each point is connected to the exchange
switching instrument by a line Ľ which after passing through the magnet M
terminates in the contact C. MC is a moving contact arm turned about the
centre CE by the toothed wheel TW which operated by the electro magnet of
which the circuit is closed by the armature of the switching relay magnet SRM.
If a point, for example A, wishes to switch on to a point B, whose number may be
four, A depresses key K four times sending a current from the battery BY into
the line L. The first current passes through the magnet M to battery BY and
joins the line L to the switching relay magnet SRM operating its armature and
advancing the contact MC one tooth, the succeeding currents advancing the
contact MC to the fourth contact C. After the switching operation, the timer
operated by the local switching magnet disconnects the magnet SRM-from the
battery BY and joins it to the moving contact MC so that there is formed a
conductor between the two points through which ringing may take place, each
current operating the magnet SRM which in turn operates the local switching
magnet whose armature now operates the timer only.
If no ringing current passes for a certain time, the timer resets the whole
instrument and all connections assume their normal position.
102. The above system involves the use of a separate magnet similar to M
and M for each point as shown in Figure 27. By the following arrangement one
is sufficient for all points. See Figure 28.
The lines L, L, from each point, for instance, A and B, are first connected to the
common contact CC, to the locking arm LA, the relay magnet SRM and the
battery BY to the wire RW and also to the fixed contacts AC and BC, the other
points being connected to the contacts CCC. The first switching current from any
point, say A, operates magnet SRM and releases the locking arm LA which under
the force of a spring and train of wheels, and at a speed regulated by a timer if
necessary and very quickly sends LA sweeping over the contacts C, C, and the
like. At the same time the common contact CC is disconnected from all the other
wires, when LA reaches the switching point's contact C, in this case AC, the current
is reestablished and the magnet SRM again operates and locks the locking arm LA
to that contact. Further switching currents passing through SRM operate the
moving contact MC turning about the same centre as the arm LA and bring it into
contact with the required fixed contact, for instance, BC.
103. The timer now disconnects the magnet SRM from the battery BY, and
connects it to contact MC as before described, ringing and speaking take place as
before described.
104. If it be necessary that the number of the switching point be automatically
sent to the required point, the signalling arm SA will, after the last switching
current, be released by the timer and by sweeping over the series of contacts or by
a simple make and break device send a number of signalling currents from the
battery BY to the point required until the arm SA touches the arm LA, and is
there stopped.
105. Where a separate magnet is used in each line, as shown in Figure 27, the
first current through any one of them may set up a stop at the contact of the
signalling point to stop the arm LA.
The passage of the locking arm or the moving contact over each fixed contact
may be used to depress the fixed contact and cut it off from the earth or return wire.
106. In Figure 29 is shown a modification wherein two or more points A and B
are each connected to the exchange EX by a separate switching wire SW and a
separate speaking or ringing wire RGW. The wire SW from each point termi-
nates in a magnet M and thence passes to a common switching relay magnet SRM
to the battery BY and to the common return wire RW. The relay magnet SRM
operates a circuit containing a local switching magnet which operates a timer as
before shown. It also moves one or more axles AL Figure 30 in such a manner
C

page_text: that the books H have a slight down and up motion from their present position, the
timer at the end of its period giving the axle AL a slight upward motion above its
present position.
107. As aforesaid, each point has also a separate ringing and speaking wire RGW
terminating in the moving contact MC special to each point. The part of the
instrument special to each point is shown in Figure 30. If a given point, for
example A wishes to speak to another point B, for instance No. 5, A taps his
switching key SK five times thus completing the circuit through contacts 1 and 2,
wire SW, magnet M, the relay magnet SRM, the battery BY and the return
wire RW, thus operating the magnets M and SRM. The magnet SRM causes the
local switching magnet aforesaid to act and turn the axle AL and the hooks H up
and down five times and operate the timer and if a sufficient interval of time elapses
since the last current is sent.the.axle--AL-will-be-turned-upwards-slightly for a
purpose to be hereinafter explained.
The office of the magnet M will now be explained by reference to Figure 30.
Each point is provided with a special apparatus as there shown, with the exception
of the axle AL which is common to every instrument, a hook H on the same being
appropriated to each instrument as shown. The first current from the switching
point passes through the magnet M causing it to attract its armature ARM carrying
the hook H 2 hinged to it and prevented from falling lower than shown by the
arm AM.
The hook H 2 pulls with it the arm AM 2 projecting from the
arm AM 3 jointed to and carried by the spring SP which also carries the spring SP 2
forcing the arm AM 3 outwards until the arm AM 4 stops it by touching the
spring SP as shown.
108. The hook H 2 drawing AM 3 with it forces the arm AM 5 under the hook H
and short circuits the magnet M. The magnet SRM being operated, the axle AL
is turned slightly downwards each time taking the arm AM 3 with it, which by the
hook H 3 operates the toothed wheel TW carrying the contact arm MC over the
fixed contacts FC, which are fixed rods shown in section and common to all
the switching instruments, until the required contact is reached, when ringing and
conversation may be carried on through the wire RGW.
it.
The first operation of the arm AM 3 carried the step S below hook H 2 and
when AM 3 is raised by the recoil spring SP the step S carries the hook H 2 with
When the timer finishes its period, the hook H on the axle AL is raised a
little and releases the arm AM 5 thus forcing the arm AM 3 to fly back out of
reach of the hook H, so that if the axle AL is operated by any other points it will
not interfere with this one. At the same time the magnet M is put in circuit with
the wire SW.
109. To release, a switching current is sent through the magnet M which again
attracts its armature ARM but this time the hook H 4 pulls the arm AM 6 of the
detent D and allows contact MC to fly back to zero, the hook H 2 then slips off
the step S into its normal position and the apparatus is ready for another call.
110. In a modification of the above instrument it may be arranged that the first
current of any series shall reset the instrument, as shown in Figure 25. Thus the
hook H 2 shall only pull the arm AM 2 into connection with the hook H, and the
timer shall cause the hook H 2 to first release the detent D and then shift towards
and operate the wheel TW as shown in Figure. 25.
111. There are some important applications of the principle shown in para-
graphs 32 and 33 where currents passing in a line with less than a certain interval
of time between them shall operate certain mechanism, currents with more than a
certain interval shall not affect the aforesaid mechanism but operate other mechanism,
and I may add that currents with a still longer interval between them may operate
neither of the foregoing mechanisms but may operate other mechanisms and so on.
112. In Figure 31, the key K when in its normal position touches the pin PN
putting the line L in connection with the speaking or signalling instrument T, and
is raised above the plane of the contacts SC, SWC, and RC. If pressed down and
turned about its centre to either of the contacts SC, SWC, and RC, it will sweep

page_text: over the intervening contacts sending currents from the battery BY to the line L
in rapid successions. They will operate the magnet M and its armature ARM
once for each current sent and by the hook H operate the toothed wheel TW.
The arm from the toothed wheel TW supports the moving hook MH, which
transmits the movement of the armature ARM 2 of the magnet M 2 to either of
the hooks SWH or RH for the operation of a switching instrument not shown.
When hook H is operated it rotates the toothed wheel TW against the tension of
the recoil spring of TW, the recoil being regulated by a timer which allows it to
move back at a relatively quick rate.
113. If one current be sent from the key K, the wheel TW will be rotated one
tooth and the book MH will be raised a little. If the circuit be opened and no
current be sent for a relatively long interval of time, the wheel TW will recoil and
nothing further happen.
114. If the person wishes to switch or operate the switching instrument, he moves
key K to the contact SWC thus sending two currents in quick succession through
the magnet M and operating the wheel TW in quick succession because the timer
aforesaid has not time enough to pull back the wheel TW between the currents
and the hook MH will be raised to the switching hook SWH. At the same time
the circuit through M 2 will be closed by the ar.nature ARM and the switching
instrument will be operated through the armature ARM 2.
115. The switching currents now sent will not rotate the wheel TW farther
because in the interval between them, the wheel TW slips back a little at the rate
of the first timer and then gears in with a much slower timer which for a relatively
long space of time will keep the wheel TW in its present position and although
hock H will operate the wheel for each switching current sent it will not cause the
wheel TW to be rotated past its present position.
116. After the switching is completed, a second or two is allowed to elapse
and the wheel TW will again slip back to the pin PN and the switching
instrument itself will connect the line L to the point required as before shown
in Patents No. 16768, 1892, and No. 11294, 1893. Ringing and resetting may be
performed in the usual manner through the switching instrument or by touching
the contact RGC with the key K and resetting by sweeping round the key K
until it touches the contact RC thus sending three currents to line, these in the
same manner as those shown for the switching operation will operate the
wheel TW three times in rapid succession and bring the hook MH to the hook RH
and reset the switching instrument.
The operator is not aware that he sends the currents in quick succession as the
movement of the key K to the particular contact required performs the operation
automatically.
117. This particular use of timers may be used anywhere two or more effects are
required and for any system of exchange described in Patents No. 16768, 1892, and
No. 11294 1893.
118. To show a further application of the same principle, see Figure 32. Four
or more points A, B, C, D, are connected by the linewire L passing through the
return wire RW through the battery BY ard each of the magnets M at the four or
more points A, B, C, D, and then returning to the keys K at each point through
which L may be connected to the return wire.
The instrument used at each point is shown in Figure 33, where M is the magnet.
above mentioned. Its armature ARM moves the hook H which operates the
toothed wheel TW carrying a spring hook H2. TW is drawn back by the
spring SP carrying the multiple hook MH engaging in the timer T. The hook H 2
is situated at a different position in relation to a timer of long period T2 at each
station in such a way that two movements of the wheel TW will bring H 2 into
engagement with the wheel TW 2 at the first station A, three at the second
station, four at the third station and so on. On approaching TW 2, the hook H 2
slides up the plane P and only when on this plane will it engage with the
wheel TW 2 for if it be propelled past the plane it slips below it and on its return
will not engage at all with the wheel TW 2.

page_text: 119. If station C wishes to ring up station B, C depresses his key K thrice in
quick succession thus operating each magnet M and moves the hook H 2 thrice
forward at all stations. At station A, it will be moved past the plane P and slip
below it. At station B, it will rest upon it and engage with the wheel TW 2, and
its effect at stations C and D will be not to reach the plane P. Therefore only
at station B will the backward motion of the hook H 2 operate the timer T2
and bring the local ringing circuit into operation so that each time the key K
at C is depressed, the bell at B will be rung and in like manner the key K at B
may be used to ring a bell at C which is automatically put into connection by the
operator there.
The instruments may all return to their normal condition if no ringing currents
pass through the circuit for a given interval of time and thus reset the system.
120. The switches shown and described in the before mentioned patent specifica-
tions and in this specification may all be used for the transmission of currents for
electric lighting but now purpose describing a switch for lighting from batteries
such as the Leclanché where the light should not be continued for any length of
time so that the ordinary switches are not admissible and presselles and pushes keep
the operator pressing as long as he wants the light. The object of this switch is to
include the action of a timer which shall open the switch after a certain number of
seconds or minutes.
121. In the first instance, the timer is at the switch itself, and the motion of
turning on the switch will store up energy in a timer which will work the timer
and after a certain interval open the switch. The timer may be arranged to
give an audible sound or reduce the light of the lamp as a signal that it is going to
release the switch.
122. The ticking or operation of a timer being objectionable in a room, in the
second form the timer is placed in a central position and is common to the
switches at the different points. The closing of any switch automatically completes
a circuit for the instant which operates the timer, and on completely closing
the switch a magnet is introduced into the tinier circuit which will at the
end of the timer's period receive a current transmitted by the timer and open the
lamp switch and its own circuit.
123. In another form, the closing of the lamp circuit energises a magnet in the
same circuit of which the function is to operate a timer, and also a magnet in the
same circuit at the lamp switch, which while the current flows will keep the lamp
switch closed but the timer after the termination of its period, cuts off the battery
for an instant and thus sets free the lamp switch and at the same time all other lamp
switches which may be closed.
124. In order to limit the necessary range of the moving contacts of the telephone
switches, use the following disposition of parts. In Figure 34 I show the moving
contact holders MC, MC 2, MC 3, and MC 4. MC can make contact with any fixed
contact on the switchboard SB, each of which is connected by a separate wire in
a flexible cable to a contact on the moving contact holder MC 2. Each contact
on MC 2 can make contact with any one of a certain number of contacts on the
switchboard SB 2. Each contact in
one group of contacts on the switch-
board SB 2 is connected by a separate wire in a flexible cable to a contact on the
moving contact holder MC 3, and each contact in another group of contacts on
the switchboard SB 2 is connected by a separate wire in a flexible cable to a contact
on the moving contact holder MC 4 and so on. Each contact on MC 3 can make
contact with any one of a certain number of contacts on the bar switch-
board SB 3 and each contact on MC 4 can make contact with any one of a certain
number of contacts on the bar switchboard SB 4 and so on for more moving contacts
similar to MC 3 and MC 4, and switchboards SB 3 and SB 4.
The bars or contacts on the switchboards SB 3 and SB + are common to all
subscribers' switching instruments and are each connected to the linewire of a
.subscriber. The contacts on the switchboards SB and SB 2 are special to the
subscriber's switching instrument..
vilre

page_text: 125. The moving contacts shown may be moved by a switching instrument or
by the hand of an operator by the handles H, H2, H3 and H4.
If a subscriber wishes to switch on to another sitbscriber for instance No. 128,
the contact holder MC is operated and makes contact with the first contact on the
switchboard SB. The contact holder MC 2 is moved so that each contact carried
by it makes contact with the second contact of its special group and similarly the
contact holder MC 4 is moved so that each contact carried by it makes contact with
the eighth contact of its special group so that the only communication formed lies
between the contact MC and the subscriber No. 128.
Dated this Seventeenth day of June 1895.
Improvements in Switch Apparatus for Use in Distributing
Electricity for Telephonic, Telegraphic, and other Purposes.
I, ROBERT PIPPETTE of 51, Upper Tulse Hill, London, S. W., do hereby
declare the uature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
1. My invention relates to improvements in switches for electric currents of all
kinds and in the operation thereof. These switches may either be operated
directly by hand or electrically. Among their uses, they are applicable to
automatic electric exchange for any system of electric telegraphy, telephony,
telautography, signalling etc., for the purpose of telegraphy, telephony, telauto-
graphy, signalling etc., and for electric power and lighting.
1A. Referring to the drawings left with my Provisional Specification:
-
Figure 1 shows a quick make and break switch as described in section 10.
Figures 2 and 3 show the methods of using strained wires for the fixed contacts
of switches, and Figure 4 shows a moving contact suitable for use with such
strained wires. These figures are described in section 11.
Figure 5 shows an arrangement of polarized armatures about the poles of an
electro magnet, as described in section 13.
Figure 6 shows an arrangement for the selective working of magnets in series,
as described in section 15.
Figure 7 shows an arrangement for operating magnets by difference of current
strength and direction, as described in sections 17 &c.
Figure 8 shows an arrangement for operating mechanism by the use of movable
conductors charged with static electricity as described in section 22.
Figure 9 shows the method of using a timer coming into operation after the
circuit is opened, as described in section 26.
Figure 10 shows a method of using a timer which is put into action when the
circuit is closed, as described in section 28.
Figure 11 shows another method of using a timer put in action when the circuit
is closed, as described in section 29.
.0
Figure 12 shows a method of using a timer put in action after the circuit is closed,
the timer period being lengthened, as described in section 30.
Figure 13 shows a method of operating a timer by quickly following currents, as
described in section 32.
Figure 14 shows a method of regulating the making and breaking of circuits by
a tinier, as described in section 35.
Figure 15 shows a method of locking a timer during the attraction of the armature,
as described in section 37.
Figures 16 and 17 show a method of utilizing one linewire for the circuits of two
or more instruments, as described in sections 39, etc.

page_text: _Figure 18 shows a method of enlarging the scope or reach of a magnet, as
.described in section 48.
Figure 19 shows another method of doing the same thing, as described in
.section 49.
Figure 20 shows various methods of limiting the action of the armature of a
magnet, as described in section 51.
Figure 21 shows another method of limiting the action of the armature of a
magnet, as described in section 55.
Figures 22 and 23 show a method of applying this invention to switchboards
worked by switch pegs, cords and spring jacks, as described in sections 58, etc.
Figure 24 shows the internal arrangements of a switch peg used in the last
mentioned system as described in sections 78, etc.
Figure 25 shows an electrically controlled switch with five lines to each point, as
described in sections 86, etc.
Figure 26 shows_a_station-key-as-used-with the above described system, as
described in section 91.
Figure 27 shows an electrically controlled switch with three lines to each point,
as described in section 101.
Figure 28 shows an electrically controlled switch with two lines to each point,
as described in sections 102, &c.
Figures 29 and 30 show an electrically controlled switch with four wires to each
point as described in section 106.
Figure 31 shows a method of controlling a switch by currents following one
another at short intervals of time, as described in section 112.
Figures 32 and 33 show switches worked on the same principle, as described in
sections 118, &c.
Figure 34 shows a method of working a multiple switch with movable switch
bars, as described in sections 124, &c.
1B. Referring to the drawings left with my Complete Specification:-
Figures 35 and 36 show a modification of the quick make and break switch shown
in Figure 1, and as described in sections 10E, &c.
Figure 37 shows another modification of the quick make and break switch shown
in Figure 1, and as described in section 10G.
Figure 38 shows a more detailed drawing of the switch shown in Figure 28, and
. as described in sections 105A, &c.
Figure 39 shows a modification of the system shown in Figure 32, and as
.described in sections 119B, &c.
Figure 40 shows the details of an electric light switch with the timer at the
-switch, as described in sections 123A, &c.
Figure 41 shows the details of an electric light switch with the timer in a central
position as described in sections 123B, &c.
Figures 42 and 43 show details of the multiple switch shown in Figure 34, and
are described in sections 125A, &c.
1c. In describing this invention, and also in the descriptions of the Patents
Nos. 16,768, 1892, and 11,294, 1893, it is quite possible that I have given names
to the apparatus and parts thereof &c. which in actual practice and work may not
technically be correct, therefore the names drawings and descriptions are to be
considered rather as giving the best information at command in order to describe
these inventions.
2. In the description of this invention, I make special reference and application
of these improvements to the systems instruments and their modifications substan-
tially shown and described and operated as specified in Patents No. 16,768, 1892,
and No. 11,294 1893. I do not however confine these improvements solely to
such systems and instruments since they may be used for electric exchange in
general whether an exchange operator intervenes or not.
3. In the aforesaid Patents, I use the making and breaking of circuits, positive
and negative currents, and timers for the purpose of operating the switching

page_text: instruments. There are other properties and effects of electricity and timers which
may be utilised for the same purpose, the particular property and effect chosen for
use in any particular case varying with the nature and duration of the current
used after the connection is made, and in'some cases with the required duration of
the aforesaid current. Therefore I may substitute or add any of the improvements
hereinafter described for the operation of the switches instruments &c. described in
the aforesaid Patents where it may be advantageous to do so.
4. The object of my invention is to utilise the various properties and effects of
electricity and those of timers for the purpose of electric switching and signalling,.
to simplify the manipulations and operations required in switching, to reduce the
apparatus necessary at all points connected, to reduce all parts to their simplest and
most efficient elements, to the end, that persons using my invention shall need no
special skill training or practice in the operation thereof.
5. For the transfer of energy from one point to another for the operation of
switching instruments the operation of parts of switching instruments and the various
signalling instruments at the different points, I make use of the properties and effects
of electricity as follows.
6. As shown in Figures 6 and 7 and others, I use the making and breaking of
circuits for the purpose of operating electro-magnets.
7. I use relays included in the circuits where it is required to reinforce the line
current or to work the instruments indirectly by local battery power.
8. As the operation of the instruments involves the making and breaking of
circuits with the consequent production of sparks at the contact surfaces tending.
to destroy them, I reduce such effects as much as possible by the employment of
infusible and inoxidizable metals for the surfaces, the use of carbon contacts,.
compound metal and carbon contacts wherein the spark is taken by the carbon,
long metal contacts for a similar reason and rubbing contacts. Sometimes I do not
break the circuits at all, but shunt the current into other conductors or short.
circuit the working circuit.
9. For suppressing the spark, I employ condensers in the usual manner to take.
the excess current. For a similar purpose, I employ accumulators formed of strips
of lead or lead wire in sulphuric acid and water, their poles being connected to the
magnets in the same manner as the poles of condensers to take the excess current
and give it up again through the magnets until they are neutralized. One or more
such cells may be joined in series as may be required. Sometimes it is only
necessary to employ a cell formed by two copper wires or plates dipping in water,
the wires being connected to the magnet in the same manner as the poles of the
above mentioned accumulators.
10. Where it is necessary that the circuit through a magnet such as M in
Figure 13 should be completed until the armature ARM reaches the magnet M,
the following switch may be used. In Figure 1, SP and SP 2 are two springs
fixed to the insulating block IB and connected to the respective poles of the magnet
circuit. SP carries an insulating block 1B 2 of the form shown of which the face F,
that nearest the projection P, is covered with a metal plate connected to the
spring SP. SP 2 carries a metal projection P only, connected to spring SP 2.
Both springs SP and SP 2 tend to press towards one another. PN is a pin
attached to the armature of the magnet or other moving part and oscillates up and
down between SP and SP 2 and striking them alternately.
In its normal position, PN touches SP and bends it up causing the spring SP 2
to follow by its own elasticity as above described and the projection P will touch
and be put into contact with the spring SP by means of the metal plate on the
face Fthus closing the circuit. On the current passing the armature of the
magnet is attracted and with it the pin PN will move downwards until it touches
the spring SP 2 and bends it down. SP following by its elasticity as above
described, the projection P will be pulled away from F and suddenly escape and
rest in the notch of the block IB 2 and thus break the circuit. On the recoil of
the armature the same process will be repeated.

page_text: 10A. The quick make and break shown in Figure 1, its modifications and the like
is of more than ordinary importance in an automatic switch of the kind shown in
Figure 28 wherein many operations formerly brought about manually at the stations
connected to it, are made by the switch itself.
10B. When the currents used are passing through the switch contacts, the contacts
should be relatively still to get the best effect for if they move
or shake
disturbances are set up in the circuits which upset the working of the switch and
destroy clear speaking on the lines connected.
10c. The movement which operates any one of the working circuits of the switch
should at a certain point be as it were independent of the movement of the switch,
otherwise the movement of the main switch being arrested exactly at the moment
of the separation of the switch contacts the motion which should separate the
switch contacts further is also arrested and the contacts being restored by the
--recoil-springs-they-again make contact and a chattering or vibration is set up and
the working of the switch stopped.
10D. The power to work a switch costs money and for economy the less power
used the better. It has been found that while it is quite practicable to work a
switch by giving it all the power it wants, it is much better to reduce the friction
to a minimum by raising the moving contacts of the supplementary switches from
the fixed contacts before altering their position and then again placing them on the
fixed contacts, such movement taking place in the same plane or at right angles or
at any other angle to that which alters their position.
MH is
10E. Figure 35 shows a modification of the switch shown in Figure 1.
the moving hook of the automatic switch of which the switch shown in the figure
forms part. The arm AM is moved up and down by the hook MH. AM is
centred at CE and is continued and terminates in the arms AM 2 and AM 3.
AM 2 and AM 3 so embrace the arms AM 4 and AM 5 centred at CE 2 that in
whichever direction about the centre CE AM 2 and AM 3 turn they strike AM 4
and AM 5 so that the arm AM 6 is raised. AM 6 carries the block IB. AM 7 is
centred at CE 3 and carries a pin PN which comes into contact with the block IB.
The spring SP tends to pull AM 7 to the left.
If the arm AM be pulled downwards, the spring SP 2 attached to AM will be
pressed against the arm AM 7. The latter will be prevented from moving by the
pin PN catching in the side of IB, but presently the arm AM 2 will touch AM 4
and lift IB out of the path of the pin PN and then the arm AM 7 will move
forward under the impulse of the spring SP 2. Similarly if AM be lifted the
arm AM 7 will be held by the block IB until the arm AM 3 touches the arm AM 5
and again lifts IB when the spring SP will draw AM 7 back.
If IB and arm AM 7 be furnished as contacts similar to IB 2 and P in Figure 1,
this switch will open and close them in the same manner.
10F. In Figure 35, I show an improvement which allows the moving contacts to
rise from the fixed contacts into the air so that they may be moved without
grinding on the fixed contacts. The moving contacts MC Figure 35, can move in
the plane of the paper when pressed by the arm AM 7 about the centre CE 4 and
thus be caused to touch the fixed contacts C C &c. on the contact board B. The
aforesaid contacts C C &c. are shown in Figure 36, which is another view of the
switch shown in Figure 35. When arm AM 7 moves to the left, the spring SP 3
raises the contacts MC from the contacts C &c. when as shown in Figure 36 they
may be moved without difficulty about the centre CE 5 without touching the
contacts C, C &c.
10G. In Figure 37 is shown a further modification of the switch shown in
Figure 1. As in Figure 35, MH is a moving hook of the automatic switch which
will engage in one of the series of steps ST the front of which is shown in the
sketch just below. The steps ST are fixed to the arm AM and the moving
hook MH by engaging at certain intervals in the different steps ST may cause AM
to take up as many positions as there are steps. AM is centred at CE, and carries
two arms AM 2 and AM 3 which so embrace the arms AM 4 and AM 5 centred
.....

page_text: at CE 2 that when AM moves either up or down they will cause the detent D to
leave one of the notches N, N 2, &c. in the quadrant Q. The detent D is kept
pressed against the quadrant Q by the spring SP fixed to the arm AM 6. AM 6 is
centred at CE 3 and carries the moving contacts MC and MC 2 which may be
brought by the operation of the switch in contact with the fixed contacts similar
to C fixed on a board or other contact support. The arm AM 7 is centred at CE 4
and transmits the pressure of the spring SP 2 to the arm AM 6. The spring SP 3
tends to draw the arm AM 6 downwards but is weaker than the spring SP 2.
When MH descends, it presses down the pin PN and relieves the arm AM 6 from
the pressure of the spring SP 2 so that AM 6 is now only acted upon by the
spring SP 3. The arm AM 3 pulls down the arm AM 5 and causes the detent D
to escape from the notch N and the arm AM6 is moved downwards by the
spring SP 3 and thus operates the contacts. On MH rising it lifts AM with it
and the arm AM 2 touches the arm AM 4 and again lifts the detent D from the
notch N 2, in which it last fell, and the spring SP 2 being stronger than the
spring SP 3 forces the arm AM 6 upwards and operates the contacts, and in
accordance with the step ST in which MH works so the contacts will be operated,
higher or lower as the case may be.
11. Formerly as described and shown in Patent Specifications Nos. 16768, 1892
and 11294, 1893, the switchboard contacts of the exchange instruments have been
formed by metal bars secured to the backing of the switchboard. 1 now also form
them of metal wires W, Figures 2 and 3 strained by screws weights or other means
over the face of the switchboard which may consist of an open framework with
studs ST at intervals, to which the strained wires are fastened by staples screws or
simply let into notches N, Figure 3. The moving contact operated by the
switching instrument is shown in Figure 4 and consists preferably of a central
metal disc D revolving on the axle shown with insulating projections or cogs C to
slip in between the contact wires W aforesaid, when the contact disc D is propelled
across the contact wires in a direction at right angles to them. The disc Dis
axled in a frame F and is operated and connected by the switchcord of the
switching instrument in the usual manner as the moving contacts described in the
aforesaid Specifications. Such wires may be placed radially and the contact wheel
rotated on an arm turning about a fixed centre.
12. I also use the passing of currents of different polarities, positive and negative,
through the circuits in order to operate polarized armatures.
13. It being at times difficult to cause the polarized needles and armatures to
retain their central position of rest between the poles of the electro magnets even by
the use of check springs, I use two or more polarized armatures about the same electro
magnet, so arranged that only one shall leave its stop at a time when attracted by
the magnet.
In Figure 5, PA and PA 2 are two polarized armatures turning about the
centres C and C2 and normally kept against the stop screws SS and SS 2 by the.
springs SP and SP 2 or equivalent device. A current in one or the other direction
will cause both armatures to be attracted and repelled one way or the other by the
poles of the magnet M: But while one will leave its stop and perform its duty,
the other will be the more strongly pressed against its stop. In a similar manner,
I may use two such magnets in series or parallel each attracting its own polarized
armature.
14. In former switching instruments as shown in Figure 1 of the Patent
No. 11,294, 1893, after the connections have been made, a magnet with a polarized
armature is left in the circuit of the joined lines to receive the resetting currents
which must be sent in different directions from either end or the subscribers'
stations.
I now arrange that the magnet aforesaid shall be put in a shunt to earth,
from the joined linewires so that like currents from both ends of the joined
linewires will affect it alike, the leakage not being sufficient to interfere with the
signalling.

page_text: 15. I also use another method of operating the magnets as shown in Figure 6.
The key K may transmit currents from the battery BY in either direction into a
circuit containing the two electro magnets M and M 2. Their cores are magnetised
by induction from neighbouring magnets or are permanent in themselves. The
recoil of the springs of the armatures ARM and ARM 2 will just overcome
the attraction of the magnets and normally keep them away from their poles. The
current in passing through each will strengthen one magnet causing it to attract its
armature and weaken the magnetism of the other so that its armature remains. The
reversal of the current by the key K will have just the contrary effect and weaken
the magnet first mentioned and strengthen the second. The armatures when
attracted will perform their prearranged duties. The two magnets may be in
parallel instead of in series as shown.
16. The armatures shown in Figure 6 may normally be attracted by and to the
-cores-of-the-magnets, the-effect-of-a-current-through-them-being-to-strengthen-one-
magnet and neutralize the magnetism of the other allowing the armature to leave
its poles and perform the prearranged duty.
17. I also use difference of current strength caused by varying the resistance
or varying the electro motive force, and also difference of direction of current as
follows.
In Figure 7, K is a key in circuit with the contact C, the resistance R,
battery BY, the electro magnet M. The armature ARM when not attracted will
rest against the stop S. SP is a spring which resists the movement of the
armature ARM when attracted a certain distance by the magnet M.
The circuit may be normally opened or closed.
I now suppose that normally the key K is kept closed. A current passes
through the circuit sufficient to cause M to attract ARM to the spring SP where
its further progress is stayed. If key K is opened, the armature ARM falls back
against the stop S and may thus complete a local circuit if required, or perform any
other required duty. If key K is pressed down so as to come into contact with C2
thus short circuiting the resistance R, the current in the circuit increases and the
armature ARM overcomes the pressure of the spring SP and is attracted further
towards the magnet M and performs any prearranged duty.
18. Similarly we may arrange that the key K shall be able to sweep across the
contacts of several resistances in series all of which may be normally in circuit.
For the magnet M, a solenoid with movable core is substituted which according to
the strength of the current regulated by the resistances in circuit will take up a
corresponding number of positions within the solenoid for the purposes required.
We may substitute for the solenoid several magnets similar to M.
The
springs SP fitted to each are arranged to give way under the varying pressures of
the magnets caused by the varying resistances inserted in circuit.
19. In place of opening the circuit shown in Figure 7, the variation. of the
currents may be obtained as follows.
To keep the armature ARM in its normal position a definite resistance R should
be put in circuit. To cause the armature ARM. to recoil, the movement of the
key K would insert further resistances, that is, instead of opening the circuit and
inserting an infinite resistance; while to bring the armature into the third position
the resistance R is short circuited or lessened by the action of the key K as
before shown. Also by decreasing or increasing the number of cells in the
battery BY by means of a key similar to K, the same effects may be gained.
Also by increasing or reducing the electro motive force of the battery BY by
inserting less or more cells in the circuit in opposition to the battery BY. In this
manner the current in the circuit may be reduced to zero or reversed.
20. Further PA, Figure 7 is a polarized armature operated by the magnet M 2,
capable of performing any assigned duty. It is operated by reversing the current
from the battery BY by a key similar to K, Figure 6, so that while the magnet M
operates its armature by difference of current strength, the magnet M 2 will operate
its armature by difference in direction of current. One maguet M may be fitted

page_text: with both the armature operated by current strength as ARM and another PA 2,
operated by direction of current. The reversing of the current may be brought
about by opposing and overbalancing the electro-motive force of the battery BY.
More than one key K, resistance R, magnets M 2, M and battery BY may be
included in the same circuit.
Also for the purpose of switching and the like, I may use circuits worked from
both ends on the single and double current duplex or quadruplex systems in order
to utilise the lines to their utmost capacity, whether such systems are formed ou
the principles of difference of current, difference of direction, difference of electro
motive force, or leakage.
21. The resistances, such as I use in the before mentioned systems and elsewhere
may be readily made out of slips of lead pencil with sliding clips on the same, and
if required with coarse and fine screw motions for the adjustment of the lengths
included in the circuits. According to the mode of manufacture, and the
ingredients of the pencils, pencils of almost any suitable resistance can be obtained
for the purpose.
22. I also make use of the static electricity generated by induction friction,
dynamically, and chemically as follows.
Figure 8 shows a key K, battery BY, P a fixed metal plane, P 2 a movable
metal plane connected to the other pole of the battery BY. P3 P3 P3 are
connected metal planes also connected to the key K and P 4 P 4 connected metal
planes also connected to the battery BY and movable about the axis AL. When
the key K is depressed it allows the free electricity from the battery BY to pass
along the circuit to the plane P and by induction and attraction on the electricity
of the opposite sign from the other pole of the battery BY in the plane P 2 to
draw the latter and operate any mechanism or circuit connected to it and in a
similar manner to attract the planes P4 P 4 in between the planes P 3, P 3, P 3,
thus turning the former on the axle AL and operating any mechanism connected
thereto.
23. With regard to the thermo effects of the electric current, I may mention the
passing of a current through a conductor, heating it, causing it to expand and
operate any mechanism connected, and on the cessation of the current, the
contraction by cooling may be used for any mechanical purpose. Such conductor
may be a wire, spring, or strip of metal.
24. The chemical effects of electricity may be used by causing a current to pass
through a liquid decomposing it. If a gas result, this may be used to displace the
liquid in a bell and raise it by buoyancy and operate any connected mechanism.
If a metal or solid result, this may be deposited on a conductor and by the added
weight draw it down and operate any connected mechanism.
25. By the combination of the various properties herein before mentioned and
also by the use of timers in conjunction, I may procure almost any number of
different effects which may be used as desired in the operation of these systems of
electric switching and signalling.
26. For the purpose of this invention, I use timers as shown and described in
Patents No. 16,768, 1892 and No. 11,294, 1893 as follows.
In Figure 9, the key K. when depressed will close a circuit containing the
battery BY and the electro magnet M causing it to attract the armature ARM
when the latter will draw the hook H forward in opposition to the spring SP. On
breaking the circuit, the spring SP draws back the hook H and operates the
timer T, so that if the circuit remains open long enough after each contact of the
key K, the timer T or hook H will effect the operation desired.
27. As a timer, I may use any of the forms shown and described in Patents
No. 16,768, 1892, and No. 11,294, 1893, which may vary according to the desired
length of the period, from the inertia of some moving part of the apparatus such as
an armature and the like, a pendulum, bellows, dash pot, and the like to a train of
wheels regulated by a pendulum; fan, or bellows, whose movement may still more
be retarded by dipping or immersing them in liquids and the like.

page_text: 28. A timer may also be operated only when the key K is depressed. In
Figure 10, the key K, when depressed, will close a circuit containing the
battery BY and the electro magnet M causing it to attract the armature ARM.
The latter in its normal position presses back the spring SP to which is attached
the book H. Therefore when ARM is attracted, the spring is released and the
hook H operates the timer T, so that if the circuit be closed long enough, the
timer will effect the operation desired.
29. Similarly in Figure 11, the armature ARM when attracted will pull and
bend spring SP attached to the toothed wheel TW and bring into operation the
timer T which will allow the wheel TW to turn at a given speed, and if the
circuit be kept closed long enough, the arm AM will then effect the operation
desired.
30. Similarly the recoil of the armature ARM in Figure 12 may be used to
raise a detent D from the toothed wheel TW. When the armature ARM is
attracted, the detent D touches the wheel TW and completes a circuit containing
an electro-magnet operating the hook H, which by a step by step movement rotates
the wheel TW in opposition to the spring SP or releases a mechanism which shall
rotate the wheel TW. Thus if the armature ARM be attracted long enough, the
wheel TW will be rotated far enough to effect the operation desired. The recoil
of the armature ARM will raise the detent D and release the wheel TW.
31. The armature ARM may also operate two timers, one to come into action
during the time it is attracted and the other after it has recoiled. In a similar
manner, it may be arranged that the armature when attracted shall slowly store
energy in a spring from which it will be released on the recoil of the armature and
may be applied to working another or the same timer if desired thus doubling the
length of the period.
At this point, it may be said in reference to the use of timers which effect a
certain operation after the circuit is closed for a certain interval of time, that the
signalling currents should be shorter in duration than the period of the timer.
32. I also use the speeds at which the currents are sent for the purpose of
operating timers. In Figure 13, K, BY, M, and ARM are used for the same parts
as shown in Figure 12. When the armature ARM is attracted by the magnet M the
hook H will engage with the first of the hooks of the multiple hook H 2, drawing
forward the spring SP. If the circuit is broken, the recoil of the spring SP will
by the hook H 3 operate the timer T at a certain speed. If the armature ARM
be again attracted before the timer has gone a certain distance and allowed the
book H 2 to retire far enough, the hook H will engage with the second hook of the
hook H 2 and thus draw the spring SP forward a greater distance and cause it to
perform some prearranged duty and so on. Thus I may arrange as many hooks as
I like on the multiple hook H 2. If in the present instance the armature ARM
be attracted after the timer has gone a certain distance, the first stroke only will be
repeated and no further action takes place. Thus for the purpose shown, when
the interval between the attractions of the armature ARM is shorter than a fixed
interval, the spring SP will perform its assigned duty, but if the interval exceed the
limit, the spring SP will only be drawn forward a certain given distance and then
recoil.
For the purpose of sending two or more currents in quick succession with one
depression of the key, a special key is used which in its descent sweeps over two or
more contacts.
33. By using this device, two or more effects may be obtained from a magnet
without change in the direction of the current as will be shown hereafter.
For instance, if currents with relatively long intervals between them be used for
signalling, groups of currents with relatively short intervals between them may be
used as shown to operate the switching apparatus.
34. A timer may also be used to act for a definite time after the first switching
current of each group, after which time the changes required take place, but this
labours under the disadvantage that the interval of time between the groups of

page_text: currents will vary and the person using the instrument will be uncertain when to
begin the next group of currents. This may be got over by using a telltale timer
at the point of similar period which shall inform the operator when the period of
the exchange timer is ended.
35. I also use timers to regulate the making and breaking of circuits in connection
with electro magnets on the instruments as follows.
In Figure 14, M represents the magnet in circuit with the key K, battery BY
the armature ARM and spring contact C. When the key K is closed, the
magnet M will attract its armature ARM, but the hook H (shown as 11 in the
figure) will rotate the toothed wheel TW or move any other mechanism required,
break the circuit at the contact C and engage the hook H 2 with the timer T, so
that before the armature ARM can again recoil and make contact at C, it will
have to operate the timer T which may be set to any required speed. This comes
in especially where the key used for switching may be kept down all the time
until the apparatus shown in Figure 14 has completed the number of breaks in the
line circuit corresponding to the number required, such breaks being noted by any
kind of signal actuated by an electro magnet in circuit near the key.
36. Where the period of a timer is longer than can be conveniently measured
by such a timer as shown at T Figure 10, I sometimes use an arrangement similar
to that shown in Figure 14 where the armature ARM causes the hook H to
operate the toothed wheel TW, which carries a pin or projecting contact or
by a simple device completes the magnet M circuit until the toothed wheel TW
shall make part or a complete revolution by a series of impulses from the hook H,
each separated by an interval measured by the timer T.
37. The timers used in this invention are sometimes locked or stopped if in
motion by the following arrangements.
In Figure 15, the armature ARM, when attracted by the magnet M, draws
with it the spring SP and when the spring SP recoils the hook H attached to it
operates the timer T. The timer may be locked on the descent of either the
armature ARM or spring SP by an arm or other projection from either of the
latter touching the wheel or pendulum or as shown, the timer T may be locked
until the armature has recoiled to its normal position in the following manner.
The armature ARM in its normal position of recoil raises the detent D from
the toothed wheel TW (shown as IW) of the timer T and frees it by pressing
back the hook shown on the upper end of the detent D and turning it about a
centre below the wheel TW, but if attracted the armature allows the detent D
to fall on the wheel TW of the timer and locks it until the armature resumes its
normal position.
38. In the same manner one timer may lock and release another by the recoil of
the first timer raising a detent from the second.
39. 1 have before mentioned the use of the duplex and quadruplex systems of
increasing the capacity of a line. In Figure 16 is shown a multiplex system for
the same purpose.
Figure 16 shows three stations A, B, C connected by one linewire L. The
instruments at stations B and C are similar to that at A now to be described.
The distributor at station A contains two series of circuit segments Numbered
from 1 to 12. For clearness, segments numbers 1 and 2 and 11 and 12 the first
and last segments of each series only are shown. The circuits of arm No. 6 are
connected to segments 11 and 12. CS is the correcting segment. An enlarge-
ment of segment CS is shown in Figure 17. It consists of two plates E and F so
shaped and situated that the correcting trailer CT when passing will be in contact
with both for a little distance. An arc of 60° includes the first circuit segment
and the correcting segment, therefore the trailers will be 60° apart as shown, and
as one leaves the correcting segment, the next will touch the first circuit segment.
After passing the correcting segment each trailer drops and will touch nothing
until it arrives at the slope SL which raises it to the level of the segments.
A portion of the slope SL may be covered with velvet to clean the trailer contacts.

page_text: There may be of course oue trailer only and the series of circuit segments repeated
all round the track of the trailer.
40. Synchronism is thus secured.
One trailer CT or more as required, called the correcting trailer, touches the
segments at a point farther from the axis than the rest, so that in its passage it
will touch the correcting segment which the other trailers miss. The arm of. the
trailer CT is also lengthened.
The path of the trailer CT is barred by the spring SP. If the correction of the
instrument require it, the trailer CT will touch the spring SP and be retarded by
it more and more until the spring SP touches the screw S, when the trailer CT
would be stopped altogether. In practice, this would not often occur as the
spring SP would be taken out of the path of the trailer CT before any stoppage
took place. When the trailer CT touches the spring.SP a local circuit including
the battery BY 2 and the magnet M 2 is closed. The office of M 2 is to retard the
When the trailer CT is in
phonic wheel or other mechanism driving the trailer.
contact with the plates E and F of the segment CS and the spring SP touches
the contact screw $2, another local circuit will be closed including the battery BY 2
magnet M3 and the contacts between the screw S2 and the armature of the
magnet M carrying the spring SP so that the circuit can only really be closed
when the magnet M attracts its armature and the trailer CT joins the segments E
and F. The office of M 3 is to accelerate the phonic wheel.
41. When the trailer CT is in contact with the plate F of the segment CS, the
linewire L on the right of the station is connected to the magnet M and a branch
of the linewire on the left of the station including the battery BY. A similar
battery may be used with advantage in a similar position at the other stations but
only one is really necessary.
42. The office of the magnet M is to lift the spring SP out of the path of the
trailer CT and to make contact between the armature and the screw S 2. The
connections of arm No. 6 with the instruments for sending and receiving are shown.
No condensers are shown.
I suggest that the connection between the phonic wheel and the trailers should
be a frictional one, as if the trailers were stopped, the wheel would not be brought
to rest.
43. If battery BY be taken out of the circuit, the trailers CT at all stations
would be stopped by the springs SP. On inspection, a circuit will be seen to be
completed at each station from linewire to linewire through the trailer CT, the
plate F of the segment CS and the magnet M. Now switch in the battery BY,
and all the magnets M will be operated, the springs SP be raised and the
trailers CT released. In practice, one phonic wheel will now and again lag
behind the others and the trailer CT will be late in arriving at the segment CS,
then the circuit through the magnets M will remain open until the late trailer
touches the segment CS when the circuit will be completed and the springs SP
raised as before.
44. I will now show how the slow wheels are accelerated and the fast wheels
retarded.
For instance, if the trailer CT of station A arrive at the contact F of the
segment CS while the others are touching segments E and F, the circuit will be
completed the armatures of magnets M at stations B and C will be attracted, the
springs SP will be raised and the local circuits through the magnets M 3 closed
and the trailers CT accelerated.
If at the moment the circuit is formed through the magnets M; the trailers CT
have advanced so that they are clear of the plate E and only touch the plate F
the springs SP will alone be raised.
If before the circuit is formed through the magnets M, the trailers CT have
touched the springs SP, they will be mechanically retarded by compressing the
springs and the circuit through M 2 being closed the phonic wheels will be
retarded. Thus it will happen, that one or other of the trailers CT will be

page_text: accelerated or retarded unless the trailer be on the neutral ground, so we may
assume that they cannot vary very much either way. It is however a good plan
to allow one station such as A to set the rate for the other trailers in which case.
the magnets M 2 and M 3 may be omitted. By allowing the spring SP a little-
more freedom, or by shortening the plate E, there is formed a neutral ground.
between the points when the accelerating magnet is operated and the operation of
the retarding magnet.
The instruments connected as shown at arm 6 may be worked by positive
currents and the correction effected by negative currents from the battery BY
acting on a polarized relay at each station sensitive only to such negative currents..
45. In a modification, the phonic wheel or other motor may be omitted and the
apparatus arranged at each station so that a current from the battery BY will
cause the magnets M to operate their armatures and store up sufficient energy in a
spring to carry the trailer of each station round one revolution, the regulation,
being applied by a pendulum or fan or other timer, the correction being attained
by the maguets M 2 and M 3 regulating the depth to which the pendulum or fan-
dips in a bath of mercury or other liquid.
46. As before shown, I transmit the motion of the armatures of magnets or
other moving parts for the purpose of rotating wheels or moving other parts by
means of hooks or pallets, and I also use propelments clutches or any escapement
such as the anchor capable of transmitting any motion received by them to a wheel
or similar device.
47. The electro magnets used have often to apply a force over a long distance..
As it is economical to keep the armature of an electro magnet in the strongest part.
of the field, I adopt the usual device of applying the power of a magnet to a lever
at a point nearer the centre or fulcrum about which it acts and take off the power
from the lever at a point situated at a greater distance from the centre as may be
required.
48. I also employ the following device for the same purpose.
In Figure 18 is
shown a magnet M whose office is to operate some device which shall in turn
operate some further device. In this case, the magnet M operates the hook H
which in turn will operate the multiple book H 2.
On depressing the key K, the magnet M attracts its armature ARM and draws
down the hook H 2 a distance of one tooth and then breaks the circuit or short.
circuits the magnet M by a device similar to an electric bell break or a break
described and shown in Figure 1 or a slide contact. By the impulse of a recoil
spring, the armature returns to its normal position and again closes the circuit or
opens the short circuit of the magnet M when the armature is again attracted as
before and so on, until the hook H 2 is stopped or the circuit is broken at the
key K. As the movement of the armature ARM may be in the strongest part of
the field of the maguet M, it may be acted upon with great power over a short.
distance and move very rapidly, so that its effect is that of a long pull while it'
takes place in a very short period of time.
49. Another device for the same purpose is shown in Figure 19. It is required
to draw the lever LV or similar device downwards. To LV is attached the rod R.
carrying the armatures ARM and ARM 2 of the magnets M and M 2. The
armatures may slide on the rod R above but their descent is prevented by the
collars CL and CL2 upon which they normally rest. The lever LV is connected.
to one pole of a battery and carries a contact C which can sweep over the
contacts C1 and C 2 respectively connected to the magnets M and M 2, the other
ends of the magnet coils being connected as required to the pole of the battery
through the wire W.
M
Contact C is normally in connection with contact C 1 thus bringing the magnet
into circuit. Upon closing the circuit of the battery by a key or other device, the
magnet M is operated and causes it to attract its armature ARM to it and by the
pressure of the armature on the collar CL will draw down the rod R and lever LV..
The contact C also moves and when the armature ARM rests on the poles of M;

page_text: contact C breaks contact with contact C1 of magnet M and sends the current
through the magnet M 2 which in turn attracts its armature ARM 2 drawing down
the lever LV still further while the armature ARM of magnet M is left on the
poles of magnet M. In this manner three or more magnets may be utilized.
50. In a modification of the above, the rod R may be rigidly fixed to the
lever LV and curved about the centre about which LV turns and the magnets M
and M 2 would be arranged in the same locus to act on the armatures ARM
and ARM 2.
51. In Figure 20 is shown a hook H employed to rotate the toothed wheel TW.
When H is operated by the armature ARM of an electro magnet or by another
moving part, the action takes place so suddenly that it is of the nature of a blow
and the tendency is to jerk the wheel TW round farther than is necessary.
I neutralize this by increasing the tension of the recoil spring SP if used, or by
increasing the pressure of the detent-or-rachet DT, or-by-increasing the pressure
of the hook H on the wheel TW when it touches it, or by inserting a spring
between the hook and its attachment to the armature.
52. I also increase the pressure of the hook H on the wheel TW as follows.
Normally the shaped projection P from the hook arm bears against the pin PN
and H is kept away from the wheel TW. The hook arm being movably connected
to the armature ARM is kept pressed towards the wheel TW by a spring SP 2
and it thus happens that when the hook is operated it touches the wheel TW in
accordance with the form or shape of the projection P bearing on the pin PN and
comes into contact and presses on the wheel TW as may be desired.
53. I also increase the pressure of the hook H on the wheel TW by fixing as
may be convenient arms or projections from the hook arm H, which as it moves
shall come into contact with fixed guides or pins and force it against the wheel TW
such as the projection P 2 against the pin PN 2, or the projection P 3 against the
pin PN 3; or the projection P 4 against the pin PN 4.
54. I also arrange for the same purpose of preventing unnecessary movement of
the toothed wheel TW, that the hook arm when operated shall cause a friction
brake to bear more or less on the wheel TW, or the hook arm itself may carry a
curved damper formed of leather or velvet which shall embrace the wheel pre-
venting any movement after the hook comes to rest.
55. In order to be more certain as to the distance the toothed wheel TW moves,
I sometimes use the following arrangement shown in Figure 21.
The hook H when operated will engage with the toothed wheel TW fixed to
the axle AL. On the same axle is another toothed wheel TW 2 in which the
detent DT may engage. DT is movably connected to the recoil spring SP which
plays between the adjustable stops or screws SC and SC 2. Normally the hook H
raises the detent DT from the wheel TW 2 but when operated it allows the detent
to fall on the wheel TW and this by engaging in its teeth confines the movement
of the wheel TW 2 and through it the motion of the wheel TW and the operation
of the hook H within certain limits as set by the screws SC and SC 2. When the
hook H rises, it raises the detent DT which latter springs back into its normal
position.
If the wheel TW 2 be set to move on the axle AL within certain limits in
relation to the wheel TW, the spring and set screws SC and SC2 may be
dispensed with.
56. I may also cause an armature to move relatively slowly by making it in its
descent to operate a timer of short period formed by clockwork, liquid or gaseous
friction, such as a dashpot or bellows, or the hook may be operated by the recoil
spring instead of directly by the action of the magnet's armature.
57. In Patents No. 16,768, 1892 and No. 11294, 1893, the switching and ringing
currents sent by the calling subscriber are in one direction while the resetting
current is in the reverse direction. As pointed out in paragraph 92 of the
Patent No. 11,294 1893, the subscriber called, B, has to ring up the calling
subscriber A by sending his resetting current. This is a complication to be

page_text: avoided if possible. I therefore arrange that the ringing current on reaching the
station called shall traverse a magnet acting on a polarized armature in such a way
that the battery connections are reversed by mercury or other switches so that
ringing and switching from either end are performed without shifting the battery
connections by hand. When the station called, B, wishes to ring off, the resetting
key is touched and the passage of the current through the aforesaid magnet will
change the poles of the battery again and the station will be operated as usual.
The changing of the battery poles may also be performed by the subscriber
called, B, by hand with any suitable switch for the purpose.
I have mentioned that these switches should change or reverse the battery but
the same result will be obtained by changing the connections of the subscriber's
station with respect to the line and the earth.
58. I will now show the adoption of this system of switching to the ordinary
multiple switchboards used in telephony wherein the connections are made by means
of switchcords, pegs, spring jacks, and the like. The place of the operator is taken
by the switching apparatus, and the subscribers themselves operate the switch by
sending one or more groups of currents of electricity.
59. The principle of the electrical parts of the switching apparatus is similar to
that shown in Figure 198 of Patent No. 11,294, 1893. The switch-cords pegs and
spring jacks may be of any convenient and suitable pattern without interfering
with the operation of the switch. The relative positions shown are those to be
recommended.
60. In the usual manner, the multiple switch, if large enough, is divided into two
or more separate similar sections each containing spring jacks representing all the
subscribers on the exchange. Each section is fitted with a switching apparatus
now to be described, and also with the switchcords of a certain number of
subscribers, each of whom may use the switching apparatus of this particular
section for inserting his switch peg into any spring jack.
61. In Figure 22, SK represents one such section of the multiple switchboard.
Some of the spring jacks are represented by the dots J, J. These are arranged in
panels in regular horizontal and vertical rows.
For the purpose of description, I will suppose that the numbers of the
subscribers on the exchange run up to four figures or digits, and that any one
subscriber A wishes to switch on to or insert his switch peg into the spring jack of
any other subscriber, B, whose number contains four digits.
62. Every subscriber including A and B, is supplied with an ordinary telephonic
equipment as shown at A Figure 23, wherein E is the earth or return wire
connection. M, a magneto, T, a telephone receiver and transmitter, BL, the bell,
1, 2, 3, 4 and 5, switch contacts. Normally 2 touches 3, when ringing 2 auto-
matically touches I, when speaking 3 touches 4. The key 7 is normally in contact
with 5. The exact detail of the telephonic equipment is not of great moment, but
each station should possess a source of electricity such as the battery BY whence
a current of electricity may be sent to the exchange for operating the switch.
The battery BY is connected to earth and the contact 6. When the key 7 is
depressed, it will leave contact 5 and touch contact 6 allowing a current to pass to
line L. As it is necessary to send a current in the reverse direction to the
switching currents for resetting the instrument, I use the magneto, which is turned
in the contrary direction to that when ringing through. Otherwise we should use
a reverse current from the battery BY in which case the key 7 would be a pole
changing awitch of some kind.
63. Referring to any one subscriber, for instance A, subscriber A is connected
to the exchange by one linewire L, which after traversing the electro magnet PM,
Figure 23, terminates in the spring contact S 8. The spring S 9 is connected to
earth. The spring S 10 is connected to the switchpeg SP by means of the switch-
cord SC. Spring S 11 is connected to the spring jacks of the subscriber. The
spring S and contact screw S2 form part of the circuit including the switching
magnet SM Figure 22, the local battery, the armature PA, Figure 23 and the
E

page_text: contact screw. S.3. Normally spring S 8 is in contact with springs S9 and S.11 and
the spring S touches the contact screw S 2.
64. Subscriber A first sends to the exchange by depressing the key 7, a group
of switching currents corresponding to the first digit of the number of subscriber B.
These pass through the relay magnet PM, the springs S 8 and S9 to earth. The
magnet PM deflects the polarized armature PA which touches the screw S3 and
closes the circuit of the switching magnet SM and the local battery. The
magnet SM operates its armature ARM carrying the moving hook MH. The
position of MH is controlled by the timer T the latter being operated by the same
magnet SM.
The deflection of the armature PA pushes the rod RD carried by the rod RD.2
centred at the point CE and connected to the hook HK forward in such a manner
that the hook HK comes in the path described_by_the rod RD.3-when-turned-about-
-the-axis of and by the rod RD 4. The operation of the magnet SM attracting
its armature ARM with its moving hook MH draws down the lever LV turning
the rod RD 4 and with it the rod RD 3 about the centre of rod RD 4 and pulls
down any hook HK which may be in the path of RD 3. Thus the hook HK of
subscriber A is pulled down, and with it the stop ST attached to the book HK
descends through the hole H in the shelf SH. For the time being the rod RD 4 is
kept in its lower position by the hook HK 2 against the pressure of a spring which
tends to replace it in its normal position.
65. The hook HK is attached to the lever LV 2 turning about the centre CE 2.
The lever LV 2 is moved by the hook HK and its other end rises moving the
lever LV 3 turning about the centre CE 3 in such a manner that the spring SP
carrying two hooks HK 3 and HK 4 is raised above the ends of the springs S
and S 8 while the other end of the lever LV 3 descends and almost rests on the
rod RD 3 when the latter is in its normal position.
66. While the hook MH is operating the lever LV it also operates the
lever LV 4 turning a rod RD 5 carrying the rod RD 6 not shown but similar to
the rod RD 3. The rod RD 6 simultaneously raises the hood HK 5.and releases
the carriage CG which up to the present time has been detained in its normál
position by the hook HK 5.
The carriage CG. is a frame carried on the rail RL by the two grooved wheels W
and W 2. The side of the rail RL is cut as a rack RK. A toothed wheel TW
engages in the rack RK. The wheel TW is connected by the rod RD 7 to a
similar toothed wheel TW 2 gearing in a similar rack RK 2 on the rail RL. 2.
These wheels TW and TW2 preserve the parallelism of the carriages CG
and CG 2, which are rigidly connected by the rods RD 8 and 1RD 9. The
carriage CG 2 is kept vertical by the grooved wheels W 3 and W 4 which are
guided by but do not necessarily rest on the rail RL 2.
67. After the release of the carriage CG from the hook HK 5, the whole system
moves to the left under the impulse of the falling weight WT transmitted by the
cord CD over the wheel W 5 until the carriage meets the stop ST which slips into
a slot in a spring striking plate. in such a manner as to prevent any. motion of the
carriage CG either to the right or left.
68. The movement of the rod RD 6 touches a lever on the carriage CG causing
the rod RD 10 to move to and fro on its. axis. The rod RD 10 is studded with
pins at intervals on the first of which the stop ST 2 normally rests. The rod RD 10
passes through the central part of the stop ST 2 where two sloping pallets are
fixed. The stop ST 2 can likewise move up and down on the rods RD 8 and RD 9
to which it is attached by the collars CL and CL 2. Every motion of the
rod RD 10 allows the stop ST 2 to fall on the next pin, every to and fro movement
allowing it to fall vertically a distance of ten spring jacks until the required ten
is reached. Any backward movement of the stop ST2 is prevented by a detent
.hook carried by it catching. in the teeth of a rack cut on one of the rods RD 8
or RD 9.
Thus the first group of switching currents has depressed the stop ST, brought

page_text: the carriage CG to the stop ST and caused the stop ST 2 to descend to the required.
division of spring jacks.
The timer T now comes into operation and shifts the hook MH into the second.
position.
69. The second group of switching are sent in the same manner and through the,
same conductors as the first group, again operating the magnet SM which again.
operates the time T and by the hook MA moves the lever LV 5 thus turning the
rod RD 5 in the reverse direction to the last. The movement of the RD 6 causes.
the escapement ES on the carriage to vibrate releasing tooth by tooth the
wheel TW 3 gearing in with the rack RK 3 and allow it to descend by the weight
of the rod RD 10. The rod RD 10 is held by the rack RK 3 and partakes of its
motion so that the stop ST 2 is lowered until it arrives at the required line of
spring jacks.
70. The second group of switching currents finished, the timer T comes into
operation and transfers the hook MH into its third position. The third group of
switching currents is sent in the same manner and through the same conductors as
the second group operating the magnet SM which again operates the timer T and
by the hook MH operates the lever LV 6 and through it the rod RD 11 axially.
RD 11 is similar in all respects to the rod RD 10 and controls the movement of the
stop ST 3 similar to the stop ST 2, and which slides along the guide rods RD 12.
and RD 13 to the left under the impulse of the falling weight WT 2 trans-
mitted by the cord CD 2. Any backward motion of the stop ST 3 is prevented
by a detent on the stop engaging in a rack cut on one of the rods RD 12
and RD 13:
71. Simultaneously the hook MH pulls down the spring SP 2 carrying the
drum DR fitted with a toothed wheel to gear with the toothed' wheel TW 4.
According to circumstances, the wheel TW 4 may be set in motion by the pulling,
down of the spring SP 2 or always be kept in motion. In, either case, the
drum DR partakes of the motion of the wheel TW 4 and begins to wind up the
cord CD 3 upon it. The spring SP 2 is kept down by the hook HK 6 fitted 'to
the armature ARM 2 of the magnet M 2. The cord CD3 is fastened to and
passes several times round the drum DR 2 on the carriage CG to a drum on the
axle of the toothed wheel TW 5 on the slide SL. After passing once or twice.
round the latter drum to which it is also fastened it terminates in the weight WT 3.
The drum DR 2 is provided with a toothed wheel on the same axle in which a
detent usually engages so as to prevent it turning in the direction of the drum DR,
but at the present moment the drum DR 2 is free as the detent above mentioned is.
forced away from the toothed wheel by the stop ST.
72. The slide SL is a frame capable of moving vertically on the guide rods RD 8
and RD 9, to which it is attached by the collars CL 3 CL 4 CL and CL 6. By
the pull of the cord CD 3, the slide is pulled up in such a manner that the cup or
clip CP moves upwards and passing over the nose N of the switch peg SP shown in
Figure 23 and also in Figure 24, until it reaches its highest point when a projection
from the interior of the clip slips over the recess R of the switch peg and holds it
against all backward pull due to the weight WT 4. Directly this happens the
circuit of the magnet M 2 and a local battery is closed and M 2 attracts its
armature ARM 2 releasing the wheel and drum DR from the wheel TW 4. At
the same time, the hook detent D centred at CE4 which has hitherto held the
slide moves to one side and then the slide SL is free to descend taking with it the
switchpeg SP and the cord SC until it is stopped by striking the stop ST2 to
which it is now connected by the hook HK 7 slipping over the pin P.
At the end of the third series of switching currents we have the switch peg
lowered to the level of the row of spring jacks in which, subscriber B's spring jack
is to be found.
73. The timer T now comes into operation and transfers the hook MH to the
fourth position. The fourth group of switching currents is sent in the same manner
and through the same conductors as the third group again operating the magnet SM,

page_text: which again operates the timer T, and now by the hook MH operates the
hook HK 2 thus releasing the rod RD 3 which springs back into its normal position
and allows the stop ST to rise, when the carriage CG under the force of the
weight WT travels to the left until stopped by the pin P 2 which also raises the
lever LV 7 turning with some friction on the centre CE 5 sufficiently to strike
the stop ST 3 when the carriage CG travels to the right. The detent of the
drum DR 2 can now engage with it and prevent any motion when pulled by the
cord CD 3.
At the same time, the hook MH operates the escapement ES 2 similar to
the escapement ES in such a manner as to allow the toothed wheel TW 6 to move
the rack RK 4 gearing in with it to the left carrying the rod RD 11 and the
stop ST 3 with it.
74. The fourth group of switching currents ended, the timer T comes into
operation and transfers the hook MH into the fifth-position-completing the-circuit
-of-the magnet SM automatically, when the hook MH is again operated and pulls
down the drum DR upon the wheel TW 4 to which it is held by the hook HK 6.
As a result, the cord CD 3 is wound up on the drum DR and the carriage CG is
brought back to the right until it strikes the stop ST 3 which lifts the ratchet or
detent off the toothed wheel of the drum DR 2, when the cord CD3 begins to
turn the drum of the toothed wheel TW 5 in opposition to the weight WT 3.
75. The wheel TW 5 gears in with the rack RK 5 Figure 23 carried on the
rail RL by the toothed wheel TW 7 and the wheel W 6. The rack RK 5 is
also kept in position by the contact of the wheels TW 7 and W6 with the
rail RL 4, the left hand portion of which is cut as a rack RK 6. The motion of
the wheel TW 5 tends to move the rack RK 5 forward towards the switchboard
carrying with it the cup CP, which is centred on the wheel TW 7. When the
wheel TW 7 reaches the rack RK 6 it gears into it and passing along turns the
cup CP up for 90° so that the nose N of the switchpeg SP is pointing directly to
the spring jack required. The wheel TW 7 now reaches the end of the rack RK 6
and is kept in position by the hook HK 8 detaining the pin P 3 but the wheel TW 5
continues to turn and forces the switchpeg into the spring jack of subscriber B
where it is retained as will be shown. The circuit of the magnet M 2 is completed
by the rack RK 5 and releases the drum DR from the wheel TW 4 when the
weight WT 3 asserts itself and turns the wheel TW 5 in the opposite direction
retracting the rack RK 5 and with it the cup CP, the halves of which are rather
feebly held together by a spring and passes easily over the back of the switch peg,
the book HK 8 is removed from and releases the pin P3 and the cup falling, the
rack RK 5 reaches its normal position.
76. Ou the slackening of the cord CD 3, the detent of the drum DR 2 which
was raised by the stop ST3 falls into gear with the toothed wheel of the
drum DR 2 and prevents any motion of the drum DR 2 when pulled by the
cord CD 3. The hook MH at the same time turns: the rod RD4 on its axis by
operating the lever LV 8 when the rod RD 3 raises the end of the lever LV 3 and
brings down the spring books HK3 and HK 4 until the springs S and S8 are
caught by the detent hooks HK 9 and HK 10. This opens the magnet SM circuit
by separating the springs S and the screw S 2. It also puts the line L into circuit
with the switchcord and peg by contacting springs S8 and S 10 and earths the
spring jacks of A by contacting springs S9 and S 11.
77. I will now explain the essential parts of the switchpeg SP. The switch-
cord SC after passing through the hole H in the shelf SH and before reaching
the switchpeg, passes through the ring R attached to the arm AM centred at CE 6.
By the pressure of a spring it tends to turn towards the face of the switchboard in
such a manner, that after the switch peg is drawn out by the cup CP, the cord is
pulled towards the switchboard out of the way of succeeding switchcords as shown
by the dotted lines.
78. Whatever may be the system of multiple switchboard employed, the switch-
peg first consists of a metal thimble TH, inside which the switchcord SC is

page_text: fastened, and the other connections made. The body of the peg consists of a
hollow electro magnet EM whose function is to attract the detent D 2 which forms
its armature.
When the peg is pushed home into the spring jack by the cup CP, the
detent D 2 catches in the face ring of the jack and thus holds the peg in the
spring jack.
Sometimes, for a purpose to be presently mentioned, the spring SP is fitted, and
when the peg is pressed home the spring is compressed. If the detent D be
attracted by the electro magnet EM, the spring SP will expel the peg from the
spring jack.
79. The electro magnet EM is in circuit with the armature PA, the contact
screw S4, and the magnet M 3 not shown of which the armature will operate the
lever LV 9 and a local battery. The magnet PM has a supplementary winding,
ormally in circuit with a local testing battery, the thimble TH and nose N, but
when the hooks HK 3 and HK 4 are operated, a spring contact is moved which
transfers the circuit of the thimble and nose alone to the other pole of the aforesaid
testing battery.
The spring jacks of each subscriber are fitted with a testing wire passing to each
spring jack. The nose of any switchpeg will come into contact with this test
wire when in the spring jack, therefore the nose of A's switchpeg is now in
contact with B's test wire thus placing it in connection with the testing battery
aforesaid.
80. Now the switchpeg is in the spring jack, a ringing current passing from A's
line through the magnet PM and B's magnet PM will deflect B's armature PA,
and by a mercury switch cut off his earth connection and so the ringing current
can pass to B's station. Conversation takes place as usual.
Directly after the peg has been pushed home in the spring jack of B, the circuit
of the magnet SM is closed by the return of the rack RK and the latter draws the
drum DR into connection with the wheel TW 4 when the cord CD 3 is again
wound upon the drum DR and drags the carriage CG with the stop ST 3 back to
the starting point, a projecting pin at the starting point pushes aside the detent
preventing the rotation of the drum DR 2 and a projecting vertical rod pushes
aside the detent keeping the slide SL in its assumed position and allows it to be
pulled upwards until it reaches the top, when the stop ST 2 is released from the
slide SL by the lever of the hook HK 7 striking a portion of the carriage CG,
and falls back on the first stud of the rod RD 10, and sets the hook of the
detent D to catch the slide SL by the pin P 4. The slide SL completes the circuit
of the magnet M 2 and releases the drum DR, and the slide SL being free falls
back on the detent D. The hook HK 5 as before shown keeps the carriage in its
normal position. At the same time the hook MH is replaced in its normal position
and the switch is ready for another call.
81. On the finish of the conversation, one or the other subscriber sends the
resetting current which is in the reverse direction to the switching currents and
the armature PA is deflected in the opposite direction contacting the screw S4 and
completing the circuit of a battery and the magnets M 3 (not shown in figure)
and EM. The armature of M 3 by means of the lever LV 9 will turn. the
rod RD 14 about its axis and thus cause the rod RD 15 to strike the hook HK 11
which has been pushed out by the movement of the armature PA transmitted by
the rod RD 16 hung from the rod RD 17 centred at CE 6, and the lever will pull
the hooks HK 3, HK 4, HK 9, and HK 10 away from the contact springs and
reset the instrument. At the same time, a current from the local battery is sent
through the electro magnet of A's switch peg, operates its armature, when the peg
will be expelled by the spring SP and then pulled up to its normal position by the
weight WT 4.
82. If another peg should be switched on to the same spring jack of subscriber E
occupied by A's switch peg, its nose N would strike the thimble TH of A's peg
and a current would pass through the supplementary coil of the magnet PM of

page_text: ·
$
the switching subscriber-from-the testing battery and by deflecting his armature PA
similarly reset the switch.
83. If a switch peg be inserted into one of B's spring jacks at another section
of the switchboard, the same effect takes place as A's spring jack's nose N touches
the testing wire which runs through all B's spring jacks and puts the testing wire in
connection with one side of the testing battery, so that the resetting circuit is
operated in a similar manner.
84. Where it is necessary to do so, the first switching current of any subscriber
will also disconnect the remainder of the subscribers belonging to that section by
an earth bar similar to the rod RD 3 and connect the switching subscriber to
earth through his own contact springs. At the termination of the switching
operation the earth is again restored.
85. In the following figures, I have only shown the systems applied to ringing
bells at the different points but other telegraphic or telephonic instruments may be
inserted and operated as may be convenient.
86. In Figure 25 is shown a system of connections of two or more points A, B,
to the exchange EX. A separate speaking or ringing wire SW, SW 2, runs from
each point to the exchange EX and there terminates in a contact similar to C, C 2.
CW (the lower wire marked SW in Figure 25 should be lettered CW) is a common
speaking or ringing wire common to all points. SWW is a switching wire common
to all points in circuit with an electro magnet M and the battery BY. RW is a
common return wire or the earth passing through each point. BW is a common
battery wire passing through each point. If batteries be used at each point and
earth used as a return, the wires BW and RW may be omitted.
87. If a point, for instance A, wishes to speak to another point B whose number
is for example No. 4, point A presses his key SK four times each time operating
the magnet M. The first current passing round the magnet M will attract the
armature. ARM and. by the hook H 4 depress the spring SP 3 and the timer
hook H 3 which engages with the timer toothed wheel and operates the timer T
and also draws away the detent D from the toothed wheel TW by means of the
hook H 2 operated by the arm AM hinged on the armature ARM thus releasing
the wheel TW if before operated and it returns to its starting point being drawn.
back by the recoil spring SP.
88. As shown above, the first current has drawn down the timer hook H3 which
is now operating the timer T, we shall find that the lever LV hinged to the timer
spring SP 3 and embracing the hook arm AM is not now in contact with the
pin PN and thus the hook H is at liberty to move towards the wheel TW being
pressed towards it by the spring SP 2 so that the next current passing round the
magnet M in operating its armature ARM will again depress the timer hook H 3
and also pull the hook H down but the latter will engage with the toothed
wheel TW and rotate TW a distance of one tooth bringing the contact arm CA
into contact with the first contact C connected to the first point and so on for next
current until the required contact is reached. The wire CW is now through the
arm CA in contact with the required point's wire SW 2 through the contact C2.
89. When the timer has finished its period, the hook H 3 rises with the
spring SP 3 and causes the lever LV to touch the pin PN and thus draw the
book H out of contact with the wheel TW and bring the hook H 2 within
the range of the detent D, so that the first current of another set of switching
currents will operate the detent D and reset the wheel TW and contact CA
as above shown.
90. After having switched on to some given point, the calling point can ring up
the given point by means of the key K 2 which disconnects the bell B from
contact 2 and transfers it to contact 1 of the key K 2 when it is to receive signals.
This key is a Morse key through which the ringing will take place as usual.
91. The key K and key K2 are compounded under one key. as shown in
Figure 26. The key K 3 as shown is kept in the position shown by a spring. and
is connected to the wire CW Figure 25. In the position shown in Figure 26, it
;

page_text: presses on the shaped spring forming contact 3 and puts it in contact with contact 2,
key K 3 is however insulated from contact 3. If depressed in its present position it:
will press the contact 4 into connection with the contact 5 thus sending a switching
current through the magnet M and operate the switch as before shown. After the
switching is finished the key K 3 is moved to the right and allows the spring SP to
rise and separating the contact 3 from contact 2 and then touches the upper portion
of contact 3. When depressed, the key K 3 leaves the upper portion of contact 3.
and touches the contact 6 thus sending a ringing current to the common line CW..
It is however quite possible to use a separate bell to receive instead of one bell 'for
both purposes.
92. In a modification, the contact CA, Figure 25, when at zero or in its normal
position makes contact with the first point's line SW, so that one switching current.
sent will reset the instrument and put the line CW in connection with the first point.
93. In a modification of the system shown in Figure 25, one or more bells may
be introduced into the circuit formed by the switching wire SWW which may ring
when the switching current is sent. This is an audible signal of the point wanted
and is very useful in a house.
91. In a modification of the system shown in Figure 25, the speaking.
wires SW, SW 2 and the like may be connected to a separate system of bells
ringing in the exchange or at any other point or points with separate indicators.
for each wire at the exchange and a common return wire passing through each
point and a key at each point which will when required separate the contacts :1
and 2 and join 2 to the return wire of the bell system for the time being when
the bell system has to be used:
1
95. In a modification of the system shown in Figure 25, the special battery
wire BW is omitted and the timer after the switching is finished cuts the
magnet M out of circuit so that the switching wire SWW for the time being
becomes the battery wire for ringing and the like, the timer being so arranged
that it reintroduces the magnet M after a certain number of seconds after the
switching is finished or after the last. ringing current is sent.
96. In a modification of the system shown in Figure 25, the special switching
wire may be omitted, and the wire CW may' be used for switching, the timer after
switching cutting off the switching magnet for a few seconds so that the wire CW
may be used as the ringing wire and the like.
97. In a modification of the system shown in Figure 25, the wires CW
and SWW are omitted the switching and speaking being carried on through the
special wires SW and SW 2 from each point, an electro magnet being inserted
in each circuit to connect the particular calling point's wire to the moving
contact CA, the timer disconnecting the switching circuit and resetting if required
or the resetting may be determined by some effect of the aforesaid magnet in the
wire of the calling point.
98. In a modification of the system shown in Figure 25, we may do away with
the common wire CW by arranging that the switching key of the switching point
for instance A shall connect the speaking wire SW to the battery wire while
switching for the following purpose.
The switch at the exchange is fitted with the locking arm similar to LA
Figure 28 which shall be released by the first switching current and allowed to
sweep over the contacts C and the like. The locking arm is in circuit with a
magnet and the battery BY in such a manner that when the locking arm touches
the contact of the switching point the timer will cut off the battery BY and
the magnet aforesaid and connect the locking arm to the contact arm CA so that
communication between the switching station and the called station will take
place through the locking arm and the moving contact arm CA.
99. In a modification of the system shown in Figure 25, each point may have a
separate instrument similar to that shown with separate switching and ringing
wires and a common return wire being used if required. Where the earth and
batteries are used at each point, the two latter wires may be dispensed with.

page_text: 100. In a modification of the system shown in Figure 25, each switching
operation consists of at least two groups of currents through the switching wires,
the first will bring the arm similar to the contact arm CA to the fixed contact
of the signalling point, after which the timer will change the hook H to the
mechanism moving the contact arm CA. and will as there shown move the latter
to the fixed contact of the point required. The former arm and the arm CA
being connected, communication between the two points may be effected. The
first current of each switching operation will reset the instrument as before shown.
101. In the system shown in Figure 27, each point is connected to the exchange
switching instrument by a line L which after passing through the magnet M
terminates in the contact C. MC is a moving contact arm turned about the
centre CE by the toothed wheel TW which is operated by the electro magnet of
which the circuit is closed by the armature of the switching relay magnet SRM.
If a point,-for-example-A,-wishes-to switch on to a point B, whose number may be
four, A depresses key K four times sending a current from the battery BY into the
line L. The first current passes through the magnet M to battery BY and joins
the line L to the switching relay magnet SRM operating its armature and
advancing the contact MC one tooth, the succeeding currents advancing the
contact MC to the fourth contact C. After the switching operation, the timer
operated by the local switching magnet disconnects the magnet SRM from the
battery BY and joins it to the moving contact MC so that there is formed a
conductor between the two points through which ringing may take place, each
current operating the magnet SRM which in turn operates the local switching
magnet whose armature now operates the timer only.
If no ringing current passes for a certain time, the timer resets the whole
instrument and all connections assume their normal position.
102. The above system involves the use of a separate magnet similar to M
and M for each point as shown in Figure 27. By the following arrangement one
is sufficient for all points. See Figure 28.
The lines L, L, from each point, for instance, A and B, are first connected to
the common contact CC, to the locking arm LA, the relay magnet SRM and the
battery BY to the wire RW and also to the fixed contacts AC and BC, the other
points being connected to the contacts CCC. The first switching current from
any point, say A, operates magnet SRM and releases the locking arm LA which
under the force of a spring and train of wheels, and at a speed regulated by a
timer if necessary and very quickly sends LA sweeping over the contacts C, C,
and the like. At the same time the common contact CC is disconnected from
all the other wires, when LA reaches the switching point's contact C, in this
case AC, the current is reestablished and the magnet SRM again operates and
locks the locking arm LA to that contact. Further switching currents passing
through SRM operate the moving contact MC turning about the same centre as
the arm LA and bring it into contact with the required fixed contact, for
instance, BC.
103. The timer now disconnects the magnet SRM from the battery BY, and
connects it to contact MC as before described, ringing and speaking take place as
before described.
104. If it be necessary that the number of the switching point be automatically
sent to the required point, the signalling arm SA will after the last switching
current, be released by the timer and by sweeping over the series of contacts or by
a simple make and break device send a number of signalling currents from the
battery BY to the point required until the arm SA touches the arm LA, and is
there stopped.
105. Where a separate magnet is used in each line, as shown in Figure 27, the
first current through any one of them may set up a stop at the contact of the
signalling point to stop the arm LA.
The passage of the locking arm or the moving contact over each fixed contact
may be used to depress the fixed contact and cut it off from the earth or return wire.

page_text: 105A. In Figure 38 is shown a detailed drawing of the switch shown in
Figure 28.
Each station, for instance A &c., is connected by a linewire LA &c. to a spring
contact AC CC &c. and also to a fixed contact such as AF CF. In the figure,
the linewire LA should be lettered LC, and the linewire LC lettered LA. When
the switch is at rest, the bar EA, which forms the earth bar as well as an important
part of the switch, contacts the springs AC CC &c. EA is in circuit with the
earth or return wire through the magnet RM, the moving contact MC and
the earth contact EC. The wire to EA is also branched to the spring CS.
CS and CS 2 are two contact springs insulated one from the other, and each
carried by one of two toothed wheels TW and TW 2 both preferably carried on
one centre CE and supplied with recoil springs similar to RS. The springs CS
and CS 2 can be made to sweep over the contacts AF CF &c. The supple-
mentary switch movement Q is similar to that shown in Figure 35. The moving.
contacts MC &c hang from and move about the centre CE 2, the fixed contacts
being secured to the board BD. The moving and fixed contacts are again shown
in the sketch just above in order to make the connections clear.
The
The moving hooks H2 and H severally move the quick make and break
switch and operate the toothed wheels TW and TW 2. The arm AM causes
the moving contacts MC &c. to partake of the movement of the arm AM 2.
electro magnet SM is in the local circuit of the battery BY, the contact LC, the
armature ARM and contact MC 3. When the armature ARM is attracted by the
magnet RM, the local circuit is closed and the magnet SM operated. The circuit
is also branched to the moving contact holder to the moving contact. MC 2 and
fixed contact LC 2.
When operated, the magnet. SM attracts its armature ARM 2 fixed to the
arm AM 3 centred at CE 3 and against the tension of the spring SP. AM3
carries the timer hook TH which operates the timer T, and also the bearings B
and B2 in which the rod EA can turn on its long axis. The rod EA carries the
moving hook arm AM 2 the arm AM 3, the arm AM4 and the bent arm AM 5.
105B. In use, I will suppose that the station A wishes to speak to station C
whose number is for instance No. 3. Normally the contact MC 2 is over the
contact LC 2 but is prevented from touching it by the arm AM 3, and the
contact MC touches EC, and the springs CS and CS 2 are at zero. A depresses
his key K, and allows a current from his battery B to pass from the station to the
exchange switch. A bell in circuit at station A informs him that the current is
passing. His key is kept down. On reaching the exchange the current is distri-
buted among all the other stations through the bar EA and the springs AC CC &c.
and a portion finds its way through the magnet RM and to earth E. RM attracts
its armature ARM and closes the local circuit. SM is operated and attracts its
armature. In the descent of the bar EA, the arm AM 3 leaves the spring MC 2
and allows it to fall into contact with contact LC 2 thus closing the local circuit.
EA then leaves the springs AC &c. so that the circuit from station A is broken
and the armature ARM returus to its back stop. EA continuing to descend, the
hook H engages with the wheel TW carrying the spring CS and propels it
forward, a distance of one contact. TW is prevented from returning by the
detent DT. The hook H 2 operates the quick make and break Q, and the moving
contacts are raised from the board BD thus breaking all the circuits. The
end of the arm AM 5 is caught by the stop ST on the armature ARM. The
armature ARM 2 is now released and all in connection begins to rise under
the tension of the spring SP but is retarded by the timer T. In half a second or
so the quick make and break is operated and the circuits again closed. The same
operation is repeated until the contact CS touches the contact AF of the calling
station when the earth circuit is again established through the magnet RM and its
armature is attracted. As a result, the arm AM 5 escapes from the stop ST,
aud EA with all connected to it is moved by the spring SP 2 until AM 5 rests
against the stop ST 2. The moving contacts MC 2 and MC are now moved so
F

page_text: that MC2 will not contact LC 2 but MC will still touch EC. The book H will
now be able to operate the wheel TW 2. As the local circuit of SM is closed
through the contacts MC 3 and LC, the magnet SM is again operated and the
hook H turns the wheel TW 2 and the spring CS 2 moves forward the space of
one contact AF &c. and is prevented from returning by the detent DT 2. The
hook H 2 operates the make and break Q and the moving contacts MC and MC2
are raised and thus the circuit is broken between MC and EC. The result is that
the circuit from station A is broken, and the armature ARM is released and
breaks the local circuit, EA rises again and the timer T is operated until the quick
make and break restores the earth circuit and the cycle is repeated. But the
closing and opening of the station A circuit causes the bell at A to ring every
time the spring CS 2 is advanced a contact and this will go on until the number of
the station required is rung out when the person at station A will lift his key_K_
and breaks contact so that no further-current-from-his battery flows to line.
Now,
if he allows a second or two to go by, the timer suffers the rod EA to rise, the
quick make and break is operated and the arm AM 5 will escape from the
stop ST 2 and all in connection on the rod EA will change its position. Now
if A depress his key K again, a current is sent to the exchange to earth and as
before the magnet SM is operated and the rod EA descends. The hook H 2
operates the make and break Q and the contact MC flies up against the contact C
thus breaking the earth and putting A's line in connection with the line of
station C through the spring CS 2, and every current that passes through RM to
station C will operate the armature ARM and close the local circuit and keep the
switch going, that is from resetting but nothing further will be operated.
Now A and C can ring and talk as they like, and provided a current is sent
through RM sufficient to operate its armature at intervals, the connection will be
kept up.
When the use of the connection is finished with, A. and Cleave their instruments,
the rod EA continues to rise and the arm AM 6 catches in and releases the
detents DT and DT 2 allowing the springs CS and CS 2 to return to zero.
The
arm AM 4 touches the stop ST3 and turns the rod EA and all the hooks into
their normal position of rest, AM 3 rises and shields the contact LC 2 and finally
the quick make and break is operated and the earth contact is again established
by the springs AC &c. and contacts MC and EC and the instrument is ready to be
used again.
105c. The number of points using one instrument will lessen the initial current
through the magnet RM, so in some forms I use a delicate mercury switch to take
the first current. This is cut out and the relay switch RM &c. brought into use
by the instrument directly the local circuit is once closed.
Should this method from any cause prove ineffectual, I place an electro magnet in
each line before it reaches the contact springs AC CC &c. or the fixed contacts.
The armature of any one when attracted depresses a common contact closing the
circuit of the magnet RM and a local battery.
Or I break the earth bar EA into sections, each of which may contact a certain
number of the springs AC CC &c. Each section of the earth bar is connected to
an electro magnet special to it and thence to a common earth E. As before a branch
from each section of the earth bar is taken to a separate insulated contact on the
spring CS which will sweep only over the fixed contacts belonging to the points
in connection with its particular section of the earth bar, and for which purpose
each spring and set of contacts are fixed at a different distance from the
centre CE.
105D. Should there be a miss from any cause when the spring CS touches the
calling station contact AC &c., it is propelled to the end until it touches
the contact DC and allows a current to pass from the battery BY through
the magnet RM and operate it as before shown. The spring CS 2 then follows as
before and by a simple switch will break the circuit with the battery BY and in the
course of a few seconds the switch will again be reset."

page_text: 105E. By the separation of the bar EA from the springs AC &c., it will be
seen that the instrument is disconnected from all the other subscribers but those
calling and called so that the other stations can tell that the switch is engaged by
the bell at any particular station failing to ring when the key is depressed.
105F. Another spring CS 3 similar to CS may be caused to pass step by step
over the contacts but not touching any until it is stopped by the spring CS, at
each step the line circuit will be opened so that the number of the calling point
may be transmitted to the calling. point and the point called. When the arm CS 3
reaches the spring CS it breaks the local circuit and the switch is operated as
before described.
106. In Figure 29 is shown a modification wherein two or more points A and B
are each connected to the exchange EX by a separate switching, wire SW and a
separate speaking or ringing wire RGW. The wire SW from each point
terminates in a magnet M and thence passes to a common switching relay
magnet SRM to the battery BY and to the common return wire RW. The relay
magnet SRM operates a circuit containing a local switching magnet which
operates a timer as before shown. It also moves one or more axles AL Figure 30
in such a manner that the hooks H have a slight down and up motion from their
present position, the timer at the end of its period giving the axle AL a slight
upward motion above its present position.
107. As aforesaid, each point has also a separate ringing and speaking
wire RGW terminating in the moving contact MC special to each point. The
part of the instrument special to each point is shown in Figure 30. If a given
point, for example A wishes to speak to another point B, for instance No. 5,
A taps his switching key SK five times thus completing the circuit through
contacts 1 and 2, wire SW, magnet M, the relay magnet SRM, the battery BY
and the return wire RW, thus operating: the magnets M and SRM. The
magnet SRM causes the local switching magnet aforesaid to act and turn the
axle AL and the hooks H up and down five times and operate the timer and if a
sufficient interval of time elapses since the last current is sent the axle AL will be
turned upwards slightly for a purpose to be hereinafter explained.
The office of the magnet M will now be explained by reference to Figure 30.
Each point is provided with a special apparatus as there shown, with the exception
of the axle AL which common to every instrument, a hook H on the same
being appropriated to each instrument as shown. The first current from the
switching point passes through the magnet M causing it to attract its armature ARM
carrying the book H 2 hinged to it and prevented from falling lower than shown
by the arm AM. The book H 2 pulls with it the arm AM 2 projecting from
the arm AM 3 jointed to and carried by the spring SP which also carries the
spring SP 2 forcing the arm AM3 outwards until the arm AM 4 stops it by
touching the spring SP as shown.
108. The hook H 2 drawing A.M3 with it forces the arm AM 5 under the
hook H and short circuits the magnet M. The magnet SRM being operated, the
axle AL is turned slightly downwards each time taking the arm AM 3 with it,
which by the hook H 3 operates the toothed wheel TW carrying the contact
arm MC over the fixed contacts FC, which are fixed rods shown in section and
common to all the switching instruments, until the required contact is reached, when
ringing and conversation may be carried on through the wire RGW.
The first operation of the arm AM 3 carried the step S below hook H 2 and
when AM 3 is raised by the recoil spring SP the step S carries the hook H 2 with it.
When the timer finishes its period, the hook H on the axle AL is raised a little
and releases the arm AM 5 thus forcing the arm AM 3 to fly back out of reach
of the hook H, so that if the axle AL is operated by any other points it will
not interfere with this one. At the same time the magnet M is put in circuit with
the wire SW.
109. To release, a switching. current is sent through the magnet M which again

page_text: attracts its armature ARM but this time the hook H 4 pulls the arm AM 6 of the
detent D and allows contact MC to fly back to zero, the hook H 2 then slips off
the step S into its normal position and the apparatus is ready for another call.
110. In a modification of the above instrument it may be arranged that the first
current of any series shall reset the instrument, as shown in Figure 25. Thus the
hook H 2 shall only pull the arm AM 2 into connection with the hook H, and the
timer shall cause the hook H 2 to first release the detent D and then shift towards
and operate the wheel TW as shown in Figure 25.
11. There are some important applications of the principle shown in Para-
graphs 32 and 33, where currents passing in a line with less than a certain interval
of time between them shall operate certain mechanism, currents with more than a
certain interval shall not affect the aforesaid mechanism but operate other
mechanism, and I may add that currents with a still longer interval between
them may operate neither-of the foregoing mechanisms but may operate other
mechanisms and so on.
112. In Figure 31, the key K when in its normal position touches the pin PN
putting the line L in connection with the speaking or signalling instrument T, and
is raised above the plane of the contacts SC, SWC, and RC. If pressed down and
turned about its centre to either of the contacts SC, SWC, and RC, it will sweep
over the intervening contacts sending currents from the battery BY to the line L
in rapid successions. They will operate the magnet M and its armature ARM
once for each current sent and by the hook H operate the toothed wheel TW. The
arm from the toothed wheel TW supports the moving hook MH, which transmits
the movement of the armature ARM 2 of the magnet M2 to either of the
hooks SWH or RH for the operation of a switching instrument not shown.
When
hook H is operated it rotates the toothed wheel TW against the tension of the
recoil spring of TW, the recoil being regulated by a timer which allows it to move
back at a relatively quick rate.
113. If one current he sent from the key K, the wheel TW will be rotated one
tooth and the hook MH will be raised a little. If the circuit be opened and no
current be sent for a relatively long interval of time, longer than the period of the
timer, the wheel TW will recoil and nothing further happen.
114. If the person wishes to switch or operate the switching instrument, he moves
key K to the contact SWC thus sending two currents in quick succession through the
magnet M and operating the wheel TW in quick succession because the timer
aforesaid has not time enough to pull back the wheel TW between the currents
and the hook MH will be raised to the switching hook SWH.
At the same time
the circuit through M 2 will be closed by the armature ARM and the switching
instrument will be operated through the armature ARM 2.
115. The switching currents now sent will not rotate the wheel TW farther
because in the interval between them, the wheel TW slips back a little at the rate
of the first timer and then gears in with a much slower timer which for a relatively
long space of time will keep the wheel TW in its present position and although
hook H will operate the wheel for each switching current sent it will not cause the
wheel TW to be rotated past its present position.
116. After the switching is completed, a second or two is allowed to elapse and
the wheel TW will again slip back to the pin PN and the switching instrument
itself will connect the line L to the point required as before shown in Patents
No. 16768, 1892, and No. 11294, 1893. Ringing and resetting may be per-
formed in the usual manner through the switching instrument or by touching
the contact RGC with the key K and resetting by sweeping round the key Kuntil
it touches the contact RC thus sending three currents to line, these in the same
manner as those shown for the switching operation will operate the wheel TW
three times in rapid succession and bring the hook MH to the hook RH and reset
the switching instrument.
The operator is not aware that he sends the currents in quick succession as the

page_text: movement of the key K to the particular contact required performs the operation
automatically.
117. This particular use of timers may be used anywhere where two or more
effects are required and for any system of exchange described in Patents
No. 16768, 1892, and No. 11294 1893.
118. To show a further application of the same principle, see Figure 32. Four
or more points A, B, C, D, are connected by the linewire L passing through the
return wire RW through the battery BY and each of the magnets M at the four
or more points A, B, C, D, and then returning to the keys K at each point through
which L may be connected to the return wire.
The instrument used at each point is shown in Figure 33, where M is the magnet
above mentioned. Its armature ARM moves the hook H which operates the
toothed wheel TW carrying a spring hook H2. TW is drawn back by the
spring SP carrying the multiple hook MH engaging in the timer T. The hook H 2
is situated at a different position in relation to a timer of long period T2 at each
station in such a way that two movements of the wheel TW will bring H2 into
engagement with the wheel TW 2 at the first station A, three at the second
station, four at the third station and so on. On approaching TW 2, the hook H 2
slides up the plane P and only when on this plane will it engage with the
wheel TW 2 for if it be propelled past the plane it slips below it and on its return
will not.engage at all with the wheel TW 2.
119. If station C wishes to ring up station B; C depresses his key K thrice in
quick succession thus operating each magnet M and moves the hook H 2 thrice
forward at all stations. At station A, it will be moved past the plane P and slip
below it. At station B, it will rest upon it and engage with the wheel TW 2, and
its effect at stations C and D will be not to reach the plane P. Therefore only at
station B will the backward motion of the hook H 2 operate the timer T 2 and bring.
the local ringing circuit into operation so that each time the key K at C is
depressed, the bell at B will be rung, and in like manner the key K at B may be
used to ring a bell at C which is automatically put into connection by the operator
there.
The instruments may all return to their normal condition if no ringing currents
pass through the circuit for a given interval of time and thus reset the system.
119A. In order to arrange the systein as shown in Figure 32 for speaking, an
extra electro magnet would be placed in circuit near the battery BY for instance
near the letter L. This maguet when operated by the current passing through it
will put a timer in action which will take the battery BY out of circuit for a definite
period after the switching is performed and restore it if no current passes through
the line for a certain time to keep the timer alive.
119B. Again in Figure 39, we do away with the necessity of returning the line-
wire to the keys K by providing a battery at each station, and earthing both ends
of the main line wire L. Contact 1 is normally in connection with the contact 2
so that when one of the keys K is pressed down at any station, the current from the
station battery BY will pass through magnet M 2 and M 2 will operate a timer in
any well known manner. When the key K is raised a postponed action of the
armature of M 2 will cause contact 1 to leave contact 2 and touch contact 3 and
transmit a current from the battery BY 2 to the linewire L thus operating the
instruments at each station as above specified. This current only lasts for a
moment and if no further current passes the timer T will operate and prevent
any further current passing from the battery BY 2 to line for a certain time, and
unless it be kept alive or in motion by current passing from the points it will reset
itself.
120. The switches shown and described in the before mentioned Patent
Specification and in this Specification may all be used for the transmission of
currents for electric lighting, but I now purpose describing a switch for lighting
from batteries such as the Leclanché where the light should not be continued for
any length of time so that the ordinary switches are not admissible and presselles

page_text: and pushes keep the operator pressing as long as he wants the light. The object of
this switch is to include the action of a timer which shall open the switch after a
certain number of seconds or minutes.
121. In the first instance, the timer is at the switch itself, and the motion of
turning on the switch will store up energy in a timer which will work the timer
and after a certain interval open the switch. The timer may be arranged to give
an audible sound or reduce the light of the lamp as a signal that it is going to release
the switch.
122. The ticking or operation of a timer being objectionable in a room, in the
second form the timer is placed in a central position and is common to the switches
at the different points. The closing of any switch automatically completes a circuit
for the instant which operates the timer, and on completely closing the switch a
anagnet is introduced into the timer circuit which will at the end of the timer's period
receive a current transmitted by the timer and open the lamp switch and its own
circuit.
123. In another form, the closing of the lamp circuit energises a magnet in the
same circuit of which the function is to operate a timer, and also a magnet in the
same circuit at the lamp switch, which while the current flows will keep the lamp
switch closed but the timer after the termination of its period, cuts off the battery
for an instant and thus sets free the lamp switch and at the same time all other
lamp switches which may be closed.
123A. The electric light switch with timer is shown in Figure 40. The wires
from the lamp and battery are L and L 2. One goes to the spring SC, the other
to the contact C. The spring SC tends to touch C and light the lamp but is kept
away from contact C by the spring SP which terminates in the handle H. The
spring SP carries the multiple hook MH gearing in with the timer T. It is plain
that if the handle H be forced downwards, the lamp will be lighted and kept alight
as long as the timer keeps the spring SP from breaking the lamp circuit by raising
the contact SC.
123B. When the timer is separated from the switch, it may be used in common
by all the circuits, the same arrangements may however be used separately for each
.circuit.
In Figure 41, L or the circle in circuit on the right represents the lamp.
K the key or switch which will light the lamp when pressed down on contact C.
Ma magnet in the lamp circuit. Its armature ARM will be attracted when the
circuit is closed and keep the key K in contact with C by the detent D. BY is the
lighting battery. M 2 is an electro magnet whose armature works a timer in any
well known manner.
If the key K be pressed down, the lamp L will be lighted, the magnet M will
be operated and the key K held by the detent D. At the same time the
magnet M 2 is operated and the timer T put into action. Its effect is to short
circuit the magnet M 2 and at the end of a stipulated period to open the main
circuit of the battery at any convenient point such as S, and the magnet M will
release the key K and extinguish the lamp. The same thing will happen to any
other key in circuit, but if the timing arrangement be special to this switch, of
course it will only open the key K.
124. In order to limit the necessary range of the moving contacts of the
telephone switches, I use the following disposition of parts. In Figure 34 I show
the moving contact holders MC, MC 2, MC 3, and MC 4. MC can make contact
with any fixed contact on the switchboard SB, each of which is connected by a
separate wire in a flexible cable to a contact on the moving contact holder MC 2.
Each contact on MC 2 can make contact with any one of a certain number
of contacts on the switchboard SB 2. Each contact in one group of contacts on
the switchboard SB 2 is connected by a separate wire in a flexible cable to a
contact on the moving contact holder MC 3, and each contact in another group of
contacts on the switchboard SB 2 is connected by a separate wire in a flexible
cable to a contact on the moving contact holder MC4 and so on. Each contact

page_text: on MC 3 can make contact with any one of a certain number of contacts on the bar
switchboard SB 3 and each contact on MC 4 can make contact with any one of a
certain number of contacts on the bar switchboard SB 4 and so on for more moving:
contacts similar to MC 3 and MC 4, and switchboards SB 3 and SB 4.
The bars or contacts on the switchboards SB 3 and SB 4 are common to all'
subscribers' switching instruments and are each connected to the linewire of a.
subscriber. The moving contacts on the switchboards SB and SB 2 are special to
the subscriber's switching instrument.
125. The moving contacts shown may be moved by a switching instrument or by
the hand of an operator by the handles H, H2, H3 and H 4.
If a subscriber wishes to switch on to another subscriber for instance No. 128,
the contact holder MC is operated and makes contact with the first contact on
the switchboard SB. The contact holder MC 2 is moved so that each contact
carried by it makes contact with the second contact of its special group and similarly
the contact holder MC 4 is moved so that each contact carried by it makes contact.
with the eighth contact of its special group so that the only communication formed:
lies between the contact MC and the subscriber No. 128.
125A. In a modification of the above, the switchboard SB contains 100 contacts
each of which is connected with a moving contact holder similar to H 3 or H4 of
switchboards containing the contacts of 100 subscribers or points which may
be duplicated for metallic circuit working. Contacts for test wires may be similarly..
introduced.
The moving contact holder is shown in Figures 42 and 43. The holder consists.
of a metal bar B to which the spring contacts C are screwed. They are arranged
radially round the bar so that only one at a time is presented to and can..
touch the contacts on the switchboard to which it belongs. The handle HN may
be of wood or metal or other suitable material. When of wood, the spring S is.
fitted to it and connected electrically to the bar B. The handle HN slides in. the
metal socket SK, fixed in the framework F supporting the switchboards. Through SK,
this moving contact holder of the first holder H, is connected to the subscriber's line
and magnet PM which cuts off his earth at the exchange as before described, or if
this contact holder be a secondary holder similar to H 3 or H 4 it is connected to.
one contact on the board SB.
The extent to which the holder is pulled out is indicated by the rings RRR &c.,
and the extent to which it is turned on its long axis is indicated by a dial at the
end as shown in Figure 43 where the weighted needle N revolving on the centre C
retains its vertical position and shows by the figures which contact C is in use. The:
end of the bar B, E, slides to and fro and turns in a ring or bearing situated on..
the back framework supporting the switchboards.
Where each subscriber is supplied with three or more contacts on the switch-
boards each contact C on the moving contact holders is multiplied, the properly
situated contacts being insulated from one another and connected by similar
sockets SK to the parts required. .
125B. The instrument is used in this manner. If a subscriber wishes to speak
to another subscriber for example No. 1286, the operator to whom the calling
subscriber is allotted receives his call and then takes the handle H allotted to him.
and turns it so that the needle N points to 1 and pulls it out to the second ring..
This operation puts the subscriber's line into connection with the moving contact
holder of the secondary switchboard 12, then the operator turns the moving contact.
handle of the switchboard 12 so that the needle N indicates the figure 8 and pulls
it out to the 6th ring when the two subscribers are connected.
The other arrangements in connection with the multiple switch, such as indicators.
and the like are similar to those at present in use.
The first moving contact holder H allotted to each subscriber is so arranged that.
on pressing it inwards, it puts the calling subscriber in connection with the operator's.
speaking instrument, and when pulled out it breaks the calling subscriber's earth
connection.

page_text: Such a switch may be conveniently placed in the handle H and operated by a
small presselle on the side, and the same or a similarly situated one may also put
the operator in communication with the called subscriber.
The ringing current from the operator or from one subscriber to the other breaks
or restores the called subscriber's earth or return by the called subscriber's
polarized magnet PM as before shown in this Specification and in Specification
No. 11294 1893.
125c. It is evident that while each subscriber has a moving contact holder H it
is only necessary to supply him with one other or secondary contact holder
such as H3 &c. as it may be removed from switchboard to switchboard as
required for use, each switchboard being fitted with a tubular continuation of
the socket SK, the lower portion of which is cut away to expose the switchboard
contacts.
Each switchboard may have subscribers' contacts--on--both-sides and used
_ accordingly, and as before stated the subscriber's contacts may be strained
wires.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. The several electric exchange systems arranged constructed and operated
substantially as described in reference to Figures 22, 23, and 24; 25 and 26; 27;
28 and 38; 29 and 30; 31; 32 and 33; 39; 34, 42 and 43; with the modifications
described and operated as specified.
2. The multiplex system arranged constructed and operated substantially as
described in reference to Figures 16 and 17, with the modifications described and
operated as specified.
3. The several electrical exchange switching instruments and apparatuses
arranged constructed and operated substantially as described in reference to
Figures 22, 23 and 24; 25 and 26; 27; 28 and 38; 29 and 30; 31; 32 and 33,
39, 34, 42 and 43, with the modifications described and operated as specified.
4. The multiplex switching apparatus arranged constructed and operated
substantially as described in reference to Figures 16 and 17 with the modifications
described and operated as specified.
5. In an electrical exchange apparatus, wires for contacts, strained, to keep them
in place, arranged constructed and operated substantially as described in reference
to Figures 2, 3, and 4.
6. In an electrical exchange apparatus, the several devices arranged constructed
and operated substantially as described in reference to Figures 1, 9, 10, 11, 12, 13,
14, 15, 18, 19, 20, 21, 35 and 36, 37, used separately or together as required with
the modifications described and operated as specified.
7. An electrical exchange for telephony or other purposes in which the connections
are made by spring jacks or sockets, cords, and switch pegs, and each subscriber can
operate his switchcord and switch peg so as to put his line into connection with any
other without the intervention of an operator.
8. An electrical exchange for telephony or other purposes in which the
connections are made by spring jacks or sockets, cords, and switchpegs, and each
subscriber can operate his switchcord and switch peg so as to put his line into
connection with any other by sending one or more series of currents to the
exchange switching apparatus, the successive currents in each series being
separated by an interval of time which is less than a predetermined time interval,
and each series being separated from the preceding by an interval of time which is
longer than the said predetermined interval of time.
9. In an electrical exchange for telephony or other purposes, a switchpeg
whether inserted into the spring jacks or sockets by the subscriber by means of
switching apparatus under his control or by an exchange operator, which auto-
matically tests the line of the called subscriber. If the line of the called subscriber

page_text: is engaged the switch peg is automatically ejected; but if disengaged, is retained ;:
and if retained is also automatically ejected on ringing off.
10. In an electrical exchange for telephony or other purposes, the switch peg.
cord and arrangement of test wires and circuits for operating same, arranged
constructed and operated substantially as described with reference to Figures 22, 23.
and 24 with the modifications described and operated as specified.
11. In an electrical exchange for telephony or other purposes, a switch formed
of fixed contacts arranged in a plane and a moving contact holder formed of a
bar carrying one or more contacts which may be brought into contact with
certain of the fixed contacts as desired, the bar aforesaid moving for that purpose
lengthways, and rotating on its long axis, rings on the handle of the said bar to
show the distance the bar moves lengthways, and an indicator on the handle to
show how far it is turned axially, with or without switches on the handle for
supplementary purposes as arranged constructed and operated substantially as
described in reference to Figures 34, 42 and 43, with the modifications described
and operated as specified.
12. An electrical exchange system and apparatus in which each subscriber may
operate his switching apparatus by first sending a series of currents to the exchange
with less than a predetermined interval of time measured by a timer between them
which will operate a selecting device which will select the portion of the switch he
wishes to operate, such timer allowing the selecting device to resume its normal
position if the intervals between the currents be longer than the period of the
timer; when the selecting device reaches the portion of the switch to be operated,.
the circuit is kept closed or another circuit is closed and another timer of longer
period is brought into action which will keep the selecting device to the portion of
the switch selected in order that it may be operated by one or more series of currents,
each current of which is separated from one another and each series separated from
the preceding by time intervals shorter than the period of the last mentioned timer..
13: The switching systems for electric lighting as arranged constructed and
operated substantially as described in reference to Figures 40 and 41 with the
modifications described and operating as specified.
14. The switching apparatus for electric lighting arranged constructed and
operated substantially as described in reference to Figures 40 and 41 with the..
modifications described and operating as specified.
Dated this 16th day of March 1896.