IMPROVEMENTS IN TELEPHONIC APPARATUS
Year: 1883

page_text: "
LETTERS PATENT to William Robert Lake, of the firm of Haseltine, Lake
& Co, Patent Agents, Southampton Buildings, London for an 'Invention of
"IMPROVEMENTS IN TELEPHONIC APPARATUS communicated to him from
abroad by Henry Clay of Philadelphia, Pennsylvania, United States of
America
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 3rd July 1883.
"
WILLIAM ROBERT LAKE of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings London "IMPROVEMENTS IN TELEPHONIC APPARATUS
communicated to me from abroad by Henry Clay of Philadelphia Pennsylvania
United States of America
This invention relates to telephonic apparatus and comprises improvements in
call bells, transmitters, receivers, and switch boards, all as hereinafter described.
In the accompanying drawings
Figure 1 is a view of the interior of the box containing the call-bells constructed
according to this invention.
Figure 2, is a vertical section thereof, and
Figures 3 and 4 are detail' views hereinafter described.
Figure 5 is a vertical section on the line x, x, Figure 6, of a transmitter
constructed according to this invention.
Figure 6 is a section on the line y, y Figure 5 and
Figure 7 is a section on the line 2, 2, Figure 5,
Figure 8 is an end view of a telephonic receiver constructed according to this
invention.
Figure 9 is a side elevation thereof.
Figure 10 is a longitudinal section on the line x x Figure 9.
Figure 11 is a transverse section on the line y, y Figure 10, and
Figure 12 is a view similar to Figure 11, certain parts being removed.
Figure 13 is a side elevation, partly sectional, of a switch-board constructed
according to this invention.
Figures 14 and 15 are top views of parts thereof, and,
Figure 16 is an end view of the parts shown in Figure 15.

page_text: Referring to Figures 1 to 4, A indicates the box of a telephone call-bell in which
is also contained the transmitter, and B indicates the hook on which the telephonic
ear-piece or receiver is hung, the same having an insulated axis a which is supported
on the frame C within the box. A.
The end of the hook B within the box is formed with an inwardly projecting
nose b and an outwardly projecting hook c, with either of which is adapted to
engage an insulated pin or stud D projecting laterally from a spur wheel E which
is mounted on a shaft F, and engages with a wheel G, the shaft H whereof carries
a spur wheel J, which engages with a pinion. K whose shaft L has fixed to it the
rotary armature M of the magnet N, the several shafts named being sustained on
the frame C. The shaft F also carries a ratchet wheel P and a coiled spring Q,
both rigidly secured to the said shaft; the said ratchet, wheel has engaging with it
a pawl R which is hung on the arm or lever of the bell hammer to be hereinafter
referred to. Adjacent to the pawl R is pivotted an elbow lever S the upper or
outer limb of which projects under the pawl R, or is otherwise connected therewith.
To the wheel E, at a right angle to the axis thereof, is pivotted a dog T, one end
of which is attached to the outer end of the coiled spring Q, and the other end is
adapted to engage with the lower or inner limb of the elbow lever S.
V indicates magnets between which vibrates the arm or lever W of the bell
hammer X, the bell or bells Y being properly supported on the box A. Z indicates
a spring for returning the hook B to its normal position, the same being properly
secured to the said hook and the frame C; and Z₁ indicates a pawl mounted on the
frame C and engaging with the ratchet-wheel P for preventing improper rotation
thereof.
Suitable wires d, e run from the armature M and magnet N, and wires f, y,
run from the hook B and magnets V to hooks A' which are secured to the rear
of the box A.
A indicates the back-board, which attached to the wall or elsewhere, is adapted
to sustain the box A and the parts thereof, the said board having plates A¹ with
which the wires / leading from the instrument to the place of service are connected,
the said plates being so disposed that when the box is hung in position, the
hooks A and the plates A are in contact and in electric connection.
.
The operation of this part of the apparatus is as follows, that is to say, the ear-
piece or receiver having been removed from the hook B, the spring Z raises the
said hook, by which action the pin or stud D is released from the hook cand
engaged by the nose b.
The passage of the pin from the said hook to the nose b sets the train of wheels
in motion and rotates. the armature M., the latter creating an electric current
which rings the call-bell of the instrument desired for communication.
After service, the ear-piece is replaced on the hook B and its weight draws the
hook downward and thus releases the pin or stud D from the nose b. Owing to
the spring which has been properly adjusted previously, tlie wheel E now
revolves until the pin or stud D is arrested by the hook c the latter having been
placed in the path of the pin or stud D by the downward motion of the hook B.
By the revolution of the wheel, the train of wheel work is put in motion, and
the current generated passes through the magnets V, causing the armature W to
vibrate and the bell haimmer X to strike the bells Y and automatically disconnecting
the wires at the central office. This disconnection is effected by the action, of the
electric current upon an automatic combination of devices hereinafter described.
The vibration of the armature W operates the pawl R, which in turn winds the
ratchet wheel P, it being held or locked by the catch pawl Z', 'Since 'the 'ratchet
wheel P and spring Q are secured to the same shaft, it is evident that the spring Q
will be wound up. To prevent its being too tightly wound, I attach to the end
of the spring opposite to that secured to the shaft F, one end of the dog T, while
the other end rests against the lower end of the elbow lover S as has been stated.
This end is so constructed as to encircle the shaft F, thus permitting the lower end
of the dog T to be in constant contact with the elbow-lever S. The end of the

page_text: elbow-lever S opposite to the end encircling the shaft F passes under the pawl R.
Should the spring Q now be wound too tightly it will draw one end of the dog T
toward the shaft F thus forcing the elbow-lever S to raise the pawl R clear of
the ratchet wheel P, as may be distinctly seen in Figure 2. This having been
done it is evident that the bell may continue to be rung by the current without
being retarded by the too close winding of the spring Q.
The electric current enters the box through one of the wires h and leaves it by
the other. These wires are respectively attached to hooks A¹, one on each side of
the box. The wire g connects one of said hooks to the magnet V, and the wire d
connects the said magnets to the revolving armature M of the generator. The
electrical current following the line of conductors thus far described, passes to,
and through, permament magnet N, and thence through wire e to a contact point
or electrode e¹. When the telephone is hung on the hook, this electrode is in
contact with the hook B, which is connected electrically with the other hook A¹,
thus completing the circuit excepting the necessary external connections between
the two wires h, h, which need not be here described. The circuit in practice will
sometimes be reversed, as it is equally operative whichever may be the direction of
the current. When the telephone is not on the hook B, the latter is drawn up by
spring Z, as shown, and the circuit is broken between it and the electrode e', The
current cannot pass through the mechanism of the call bell under such circum-
stances, but will pass down the wire f to the said hook and thence directly away
from the said mechanism through electrical connections which need not here be
described.
As described, that portion of the instrument relating to the stud or pin D and
nose and hook b, c, is for exchange lines, giving a short alarm for "on
and long
ring for "off." In using the instrument for private purposes where the alarms are
just the reverse, I place the extension of the hook B underneath the shaft F instead
of overhanging the same, and allow the stud or pin D to be at rest on the lower
side. It is evident that thus I get the long ring upon removing the ear-piece, and
the short one upon replacing it.
The current generated by the mechanism in one bell or signalling instrument is
not sufficient to wind its motor. The spring Qis wound by the action of the
armature lever W and the intervening devices, the said lever being caused to
vibrate by the magnets V, as their polarity is changed by the current created by
the generator of the central office or distant station. At the same time this
current rings the bells Y by the stroke of the hammer X carried by the said
armature lever. During this operation, the mechanism in the case A is motionless
except the said armature lever, the pawl R carried thereby, the wheel P, and the
arbor F to which the inner end of the spring Q is attached. When the mechanism
referred to within the case A is in operation, it partly winds its own spring Q and
also winds the corresponding spring of a distant instrument as before stated, and
of as many instruments as are on the circuit. These devices are used in connection
with a strong generator at the central office, the main dependence being on the
currents created thereby.
Referring to Figures 5, 6 and 7, A indicates the box of the transmitter having
the usual opening a, and B indicates the sounding board which is secured within
the said box and has firmly attached to its centre a carbon block C.
D indicates bars, strips, or plates of metal, the outer ends of which are fixed to
pieces E of metal or other suitable material, the said pieces being firmly attached
to the sounding board or diaphragın B. The inner ends of the plates D have
secured to them platinum points or electrodes F which are in contact with the
carbon block C, as more clearly shown in Figure 6. A wire G is connected with
one of the plates D and the post d. A wire H is connected with the other
plate D and passing through the primary circuit of an induction coil J of usual
construction, is connected with the post b, the said coil being properly secured to
the box A. The posts b, d, are connected with a battery or other source of
electricity as usual.

page_text: The fine wire of the coil envelopes the coils of the wire H and has its outer ends
connected with the posts c, c, which are connected with the line and ground
respectively as usual, the core of the coil being a bundle of wires e, as shown in
Figure 5.
It will also be seen that the block C forms a bridge to the two electrodes, the
whole being arranged in series in an electric circuit whereby the current passes
undivided from one electrode to the other by the carbon block or bridge, thus
giving two distinct and independent points of electrical variation by receiving
vibratory effects from four distinct points of the sounding board or diaphragm and
causing the enunciation to be more perfect.
I am aware that it is not new to form a transmitter with two electrodes which
impinge upon the diaphragm and are included in the circuit-so as to cause the
current to pass in multiple are through the instrument. I am also aware that it is
not new to support the two electrodes on the diaphragm.
Referring to Figures 8 to 12. A indicates a compound or complex magnet
formed of the poles or limbs a, a. b connected as at a¹, the poles a, a, being northi
and the pole b south, or vice versa.
B indicates the cap of the ear piece or receiver C; and D a spool which is secured
within the said cap B, at the back thereof, and has the legs of the magnet A passed
through it, so that their ends project beyond the inside thereof.
To the ends of the poles or limbs a. a, is secured an annulus E with, which is
magnetically connected a diaphragm F, it being noticed that the pole b occupies a
position adjacent to the inner face of the centre of the diaphragm, but is not in
contact therewith, as more readily seen in figure 10.
G indicates à coil of wire which is within the spool D the said wire enclosing
the entire magnetic field, that is to say, the poles a, a. and b collectively, but not
surrounding any one of said poles individually. This wire coil forms part of an
electric circuit, being connected to binding posts and screws G¹, G¹, and is the
magnetizing helix of the magnet. If desired, a permanent magnet may be
employed instead of a temporary one.
The action of the current coming from the connected instrument over the wires
which enter or are secured to the posts G¹ is continued through the coil G around
the entire magnetic field, and as the current varies, the magnetism in the magnet
also varies and exerts its action on the diaphragm F causing the same to vibrate,
and thus to emit sounds corresponding to those received by the instrument at the
other end of the line.
It will be seen that as the diaphragm is firmly connected with the poles a of the
compound magnet through the annulus E, and the said diaphragm free to move
opposite the pole b, its vibrations become more violent and the transmitted sound
more audible.
By the use of the magnet and passage of the wire of the coil G in planes at a
right angle to the axis of the pole b and partly around the two poles a. I obtain an
instrument which will convey and deliver the sound with but slight loss of its
intensity.
The diaphragm acting as a keeper being in close proximity to the south pole and
magnetically connected with the north pole, augments and strengthens the magnetic
curves and causes the instrument to continually become more effective in action
instead of diminishing.
-
ts
By winding the wire in an adverse direction upon the centre pole, it augment
the magnetic action of both the north pole and south pole to a greater degree than
when wound in the same direction around all poles. Because of the centre pole
being in opposition to the other poles the magnetic current induced in a coil of wire
in its proximity would be in a degree opposed to a current induced in the same
coil from the outer poles, therefore by having the coil adversely wound or twisted
or crossed upon the centre pole to correspond with the magnetic curves there the
same as in the outer poles, I increase the electromotive force of the instrument in
proportion to the strength of the said magnetic curves; this, however, is but one

page_text: coil not surrounding any one pole individually, but all the poles collectively as it is
not three coils on three poles, but one coil on three
Referring to Figures 13 to 16. A indicates a perforated metallic plate in
electrical, connection with the telephone at the central office, and B indicates a
magnet which is properly supported on a base B₁ to which the plate A is attached.
C indicates an armature for the electro-magnet B. This armature is mounted on
the base B¹, and two catches D D are pivotted to it at the end opposite to the said
magnet. Two levers. E E are pivotted to the said base and are arranged to abut
respectively against the said catches, D, D, when in normal position. This position
is upright as shown in the drawings but a horizontal or inclined arrangement may
be adopted instead. The said levers are provided with springs or weights for
holding each of them in said normal position and they are insulated from the said
catches at the points of contact. They are also insulated from each other by the
base B¹ which is a non-conductor of electricity..
F indicates the line wires which lead to the subscribing stations each wire
depending from the plate A through one of the perforations thereof and having at
the top a metallic piece G which is held in contact with the wall of the perforations
of the plate A, the wire having an attached weight H or being otherwise weighted
to insure the contact of the piece G and plate A. The top of each wire terminates
in an eye J, which, when the wire is raised, may be fitted on either of the two
levers E, and to each wire between the said eye and, the piece G is secured an
insulating plug K, whereby the wires may be handled and operated with safety.
To complete the circuit a wire extends, as shown, from ground 1 to the
telephonic apparatus or instrument of the subscriber on line 31. The circuit is
then through the said ground 1, the instrument on line 31 the line wire F 31 of
the said instrument, the plate A, thence through a wire to the central office
telephone and thence through a wire to ground 2.
The operation is as follows, that is to say:-When subscriber N° 31 wishes to
communicate with some other subscriber, he first removes his telephone or receiver
from its hook, which forms part of the signalling instrument or call hereinbefore
set forth. As described, this removal allows the mechanism of the said signalling
instrument to close the circuit with the central office through the connections
above described. After the central office learns the requisition from subscriber
N° 31 the operator takes the eye J 31 of line wire F 31 and attaches it to lever E.
In so doing the eye J 31 is necessarily brought into electrical contact with the
catch D for the said lever and lifts the said catch. As this catch is in metallic
connection with the generator by means of the wire C¹, a momentary circuit is
established through the telephone of subscriber 31, and this produces a gurgling
noise which notifies him that his requisition is attended to.
The wire F and eye J of the subscriber who is called for, are then manipulated
in like manner, and when the said metallic eye raises the catch D with which it
comes in contact it completes a momentary circuit for the said subscriber's notifi-
cation through the said catch and connections, like those above described, except
that the signalling instrument, and not the telephone, of the latter subscriber is in
the said circuit. He will then be notified by the sounding of his bell.
Both the eye J 31 of the first named subscriber and the eye J 37 of the latter
subscriber (see Figure 13 for latter eye) are by, this time in electrical contact with
their respective levers E on which they are hung. The instrument. 37 of this
latter subscriber has ground connections and line wire connections similar to those
of instrument 31. The circuit is then from ground of, instrument 31,,through its
ground wire, the said instrument, the line wire F 31, the eye J 31, the lever E
through wire to the magnet B, from, the magnet B. through wire to the other
lever E on which the eye J 37 is hung, thence through the said eye and the line-
wire F 37 through the instrument of subscriber 37 and its ground wire to the
ground.
When the parties 31 and 37 have finished talking, the telephones of their

page_text: .apparatus, which causes the mechanism of the latter to be set in motion. This
generates a current of electricity as hereinbefore described and this current (which
flows through the circuit last described) is of sufficient strength to magnetize the
cores of the magnet B and attract the armature C, thereby raising the catches D
from the levers E. The weight H of the respective telephone wires F will then
cause the said levers to turn outwardly until the eyes J drop off from them, thus
breaking the current, The springs or weights of the said levers then return them
to their normal positions and the catches D fall again by their own weight (the
armature being no longer attracted) into the position shown in Figure 13.
Having thus fully described the said invention as communicated to me by my
.foreign Correspondent, and the manner of performing the same, I wish it understood
that I claim,
First In a telephonic call-bell, the hook B formed with a nose b and hook c,
in combination with the spur wheel E. having a pin or stud D; the gearing G,
J, K, the rotary armature M, and the magnet N, substantially as, and for the
purpose, set forth.
Second The hook B, in combination with the ratchet wheel P, the pawl R, the
arm or lever W of the bell hammer, the bell or bells Y and the magnets V
substantially as, and for the purpose, set forth
Third. The pawl R on the bell hammer arm or lever, in combination with the
elbow lever S, the dog T, the coiled spring Q, the spur wheel E having a stud D,
and the shaft F, substantially as, and for the purpose, set forth
Fourth. The box A, in combination with the back board A" having plates A1,
and with hooks A¹ which are secured to the said box, substantially as, and for the
purpose set forth.
Fifth In a transmitter for telephones, a sounding board or diaphragm in
combination with a carbon block attached to the said diaphragm, and two
supported electrodes, the said carbon block forming a bridge to the two electrodes,
the whole being arranged in series in an electric circuit, whereby the current
passes undivided from one electrode to the other, substantially as described
Sixth. In a transmitter for telephones,, a sounding board or diaphragm in
combination with a carbon block centrally attached thereto, and two supported
electrodes also attached to the said diaphragm, the whole being arranged in series
in an electric circuit, whereby the current passes undivided from one electrode to
the other, substantially as, and for the purpose, set forth.
Seventli. A magnet having three poles a a b the outer poles a a being of polarity
opposite to that of the central pole b, in combination with a helix or coil of wire
surrounding all of the poles collectively and passing in planes at a right angle to
-the axis of the said poles but in an adverse direction around pole b to the wire
partly surrounding the poles a a, substantially as shown and described.
Eighth. A magnet consisting of three or more limbs, the centre one being of
opposite polarity to the outer ones, collectively, surrounded by a helix or coil of
wire, but in adverse direction, around pole b to poles a a, in combination with an
armature or plate magnetically connected to the outer poles but free from the
centre one, substantially as and for the purpose, set forth
Ninth. A perforated metallic plate in electrical connection with the central
office telephone, in combination with catches and gravitating wires which are held
in contact with the said plate when not in use and adapted to be moved to form a
circuit through the said catches and the central office generator, while placing
different subscribers in communication.
-
Tenth. A magnet in combination with an armature having catches and levers or
electrodes, the said magnet .being included in a circuit between two connected
stations, substantially as, and for the purpose, set forth.
Eleventh. The perforated metallic plate connected with the central office
telephone, in combination with the wires having metallic pieces G, substantially
as, and for the purpose, set forth,

page_text: Twelfth. The combination of the line wires having the eyes J with the levers E
and the perforated plate, substantially as set forth,
Thirteenth. The perforated plate, in combination with the wires having metallic
pieces G, eyes J and insulating plugs K, substantially as, and for the purpose, set
forth.
In witness whereof I the said William Robert Lake have hereunto set my
hand and seal this Third day of July in the year of our Lord One thousand eight
hundred and eighty three.