Improvements in Electrical Signalling Apparatus.
Year: 1889

page_text: COMPLETE
SPECIFICATION.
[Communicated from abroad by ALFRED WALKER JONES, BENJAMIN FRANKLIN JONES,
and EDWARD LOWE MARTIN, all of Kansas City, Jackson County, State of
Missouri, United States of America, Gentlemen.]
Improvements in Electrical Signalling Apparatus.
I, OLIVER IMRAY, of No. 28 Southampton Buildings, Chancery Lane, in the County
of London, Fellow of the Institute of Patent Agents, do hereby declare the nature
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:―
My invention relates to apparatus. for the electrical transmission of signals at
different points upon a continuous conducting line.
The operator at a telegraphic or telephonic station in order to call any station on
the line, usually transmits impulses in a series constituting the "call" for that
particular station, but these impulses act on the instruments at other stations requiring
the operators at these to give attention in order that they may know whether the call
is addressed to them or not. Upon telephone lines also, the frequent, sometimes
almost continuous, ringing of the call bell is a source of great annoyance.
It is therefore desirable to have simple and practically accurate means whereby a
series of signals constituting a call for one station can be transmitted without affecting
the call instruments at others of the stations.
In warfare, various means have been contrived for exploding torpedoes and mines at
the exact time when their destructive power is greatest.
My invention is especially applicable for this purpose, by connecting the conductor
to the explosives through apparatus so arranged that any one of the explosives can be
fired without affecting the others.
My apparatus is also adapted to bring into action instruments such as call bells,
visible or other signals which will respond only to a particular combination of impulses
and will to any different combination respond only partially or not all; the completed
operation closing a local circuit in which the signal is included.
I also provide simple means whereby, from a central or controlling station, a given
combination of electrical impulses may be automatically transmitted, and whereby,
also an initial series of alternate makes and breaks are sent to put all the instruments
in operative condition, each ready to receive the combination of impulses for which
it is suited. This combination can then be sent, affecting only the instrument
suited to it.
The accompanying drawings represent apparatus according to my invention, as I
shall now describe.
Fig. 1 is a side elevation and Fig. 2 is a plan of the apparatus.
Fig. 3 is a diagram showing the several circuits and illustrating the mode of
operation.
Figs. 4 and 5 are side views in detail of the escapement in two different
positions.
Fig. 6 is a vertical cross section of the escapement.
Fig. 7 shews to an enlarged scale in side view and plan, the forms and positions of
the escapement pins or keys.
Fig. 8 is a side elevation showing a modification.
1 is a base of wood, or other suitable material from which extend two uprights 2
connected at the top by a cross bar 3, which, as well as the uprights 2, is preferably
of conducting material. A little distance below 3, adjustable centres 4 and 5 carry a
rock spindle 7 having a projecting arm 8 with a contact piece 9 which when the arm 8
rises meats an adiustable contact 10.

page_text: 1
Depending from the rock spindle 7, extend downwards two radii 12 carrying a
curved plate or are 13 concentric with the axis of 7.
A short arm 14 projecting from 7 is connected by jointed links 15 and 16 to a
soft iron bar 17, the end of 16 passing loosely through the end of 17. The bar 17
is pivotted at its other end to a support 18 which may be one of the cores of an
electro magnet 18ª as shewn in Fig. 1, or may be simply a bracket as shown
in Fig. 8.
The rock spindle 7 has also an arm 20 carrying a weight 19 nearly vertically over
the centre, so that the weight exerts its minimum force when the spindle is in normal
position as shewn in Fig. 1. In order to retard the movement of the rock spindle 7
and its arms, I connect the end of the arm 8 to the rod 21 of a loose piston working
in a cylinder 22 which is charged with oil or other liquid not liable to be affected by
changes of temperature.
From one side of the arc 13 project keys 23 having the form of double and single
staples, arranged as hereafter explained.
Below the arc 13 is attached a concentrically bent bar 24 carried by legs 25,
which are bent at their lower ends to a right angle as shewn in Fig. 6. The ends 26
of the bar 24 are prolonged beyond the legs 25 and are curved downwards.
On the base 1 is placed an electro magnet 27 having its armature 29 on a lever 28
fulcrumed at 28ª and acted on by a spring 30 attached to a
adjustment.
screw 31 for.
Set screws 33 and 34 form stops for the lever 28 when it is caused to vibrate by
electrical impulses exciting the magnet 27.
To the armature lever 28 is attached a rod 35 of such length that its end is vertically
below the rock spindle 7 at the side of the are 13. At the end of the rod 35 a finger 36
projects towards the are 13 and has its end turned down as shewn in Fig. 6, its
length being such that it may overlie and engage with the keys 23 as will be
explained.
The rod 35 has projecting down from it a plate 37 having its lower end formed as a
chair 38 having a fork 39 projecting up from it directly under the end of the
finger 36.
The two diverging branches 40 of the fork have pivotted between them an
escapement finger 41, the pivot of which is surrounded by a spring.42 urging the
finger towards the left. The pivot of 41 lies directly under the end of the finger 36.
Projecting laterally from the chair 38 is a bar 43 having attached to its end a piece
of insulating material 44, carrying a metal plate 45 curved back upon itself so that
its free end is directly over the curved bar 24.
On a bracket 46 is pivotted an arm 47 the free end of which lies beneath the
insulating piece 44 and is urged upwards by a spring 48 towards a stop 48°. From
the bracket 46 projects a contact piece 49 with which the arm 47 may make contact
when it is depressed (Fig. 4).
The keys 23 projecting from the are 13 are in the form of single and double
staples, the single representing a Morse dot and the double representing two dots in
succession or a dash.
These keys and the intervals between them are arranged in any predetermined
order, to express a combination of long or short electrical impulses.
Between successive staples having open spaces 50 there are intervals 51 of width
equal to the space 50. Also the staples may be not only single and double, but also
triple or multiple according to the combination desired. The last of the keys 23 has
a projecting end 36ª on which the finger 36 normally rests.
The apparatus so far described being the receiver at a local station has electrical
connections arranged as shewn in Fig. 3, where L is the line wire or cable in which is
included at each local station a relay R to close the circuit of a local battery L, B, with
the escapement magnet 27. A short circuit is formed for the local battery by a wire 52
from one pole to the curved contact. plate 45, and a wire 53 from the other pole to
the are 13 and bent bar 24. The magnet 18 lies in an independent circuit formied

page_text: by a wire 54 from one pole of another battery B to the contact pieco 49 and a
wire 55 leading from the arm 47 to the other pole of the battery. There may also
be a signal circuit having a battery B' and a call bell 56 which circuit is closed when
the contact 9 on the arm 8 is brought against the contact 10.
Assuming that by a key 57 or otherwise a series of electrical impulses are sent
along the line exciting the escapement magnet 27 at each impulse, the armature
lever 28 is caused to vibrate accordingly.
When its rod 35 is raised lifting the finger 36 from 36" and so releasing the first,
staple, the point of the finger 41 engages with one of the staple bars and the are 13
is then caused by the weight 19 to swing to the right as far as the diverging
branches 40 of the fork 39 permit. The extent of swing may be over two of the
spaces 50, if the impulse transmitted is of sufficient length to give time for the arc
moving as far as the escapement finger 41 permits. If a very brief impulse such
as that for a dot, is transinitted, the finger 36 is raised and immediately dropped,
allowing the are 13 to move only so far that the bent end of the finger 36 engages
in the next succeeding space 50 of the staple. If the next impulse should also be
equivalent to a dot, the finger 36 will drop through the interval 51, the insulating
piece 44 will then depress the arm 47, closing the independent circuit of the
magnet 18 so that its armature 17 is attracted, moving back the rock spindle 7
until the arc 13 is returned to its original position. At the same instant, the curved
plate 45 makes contact with the curved bar 24, short circuiting the battery L B, and
cutting the escapement magnet 27 out of circuit, thus preventing any impulses sent
along the line from acting on the finger 36 so as to interfere with the return of
the arc 13 to its normal position.
If the operator sends the combination of long and short impulses suited to the
arrangement of the staples on 13, he effects the step by step movement of the arc 13
throughout its complete stroke so that its final movement, bringing 9 and 10 into
contact, closes the signalling circuit and operates the call bell or other signal.
It being understood that upon a main line L. there are a number of apparatus such
as I have described at the various stations, each having an are 13 in which there is a
particular combination of the staple keys and intervals suitable for long and short
electrical impulses, an operator at the main station, knowing the special combination
belonging to each apparatus can call any particular station by manipulating the
transmitting key in such manner as to express the combination by which that station
is distinguished from the others. The other instruments will partly respond to the
series of impulses, but in all these, the fingers 36 will sooner or later drop through an
open interval 51, causing the parts to be restored to their normal position.
In order to secure accuracy of transmission of the impulses, instead of using a key
worked by hand, I may connect the line with an automatic instrument by which any
given combination of long and short electrical impulses may be transmitted, this
instrument being arranged so as in the first place to restore all the arcs 13 of the
various apparatus to their normal position, ready to receive the action of the impulses
to be transmitted. This automatic apparatus, as shewn in Fig. 3, consists of a con-
ducting disc, or cylinder 58, having in its periphery a series of open or insulated
spaces 59 with intervals 60 of lengths suited to the particular set of impulses to be
transmitted. This cylinder or disc is in electrical connection with the main line, and
a brush 61 resting upon its periphery is in connection with the battery. At a certain
point there is an interval 62 upon-which the brush normally rests, closing the main
fine circuit. As the disc or cylinder is rotated in the direction of the arrow, the
brush bears on a set of spaces 63, and intervals 64, giving successive short impulses
by which all the various apparatus are restored to their normal position. There is
then a long "make" 65 giving time for the ares 13 to recover their norinal positions
and the fingers 36 to come to rest upon the initial keys in each case. After the
make 65, come the spaces and intervals suited to the particular combination to be
transmitted.
The magnet 18 shewn in Fig. 1 may be arranged as shown in Fig. 8, and, instead

page_text: of the dash pot 22, an electro magnet 66 the circuit of which is closed by the ascent of
the armature lever 17, may by attracting an armature on a lever 67 connected by a
link 68 to an arm on the rock spindle 7, give the required retardation to the
movement of the are 13 and its swinging frame. As this retardation is required
when the arc 13 swings from its normal position toward the point where the circuit
of the battery B₁ is made, but not while the arc moves back to its normal position,
the lever 17 which is raised by a spring 17" immediately after the restoration of 13
is effected, carries a contact, by which the circuit of the retarding magnet 66 is
closed, when the circuit of the restoring magnet 18" is opened, but when the circuit
of 18 is closed attracting the lever 17, the circuit of the retarding magnet 66 is
opened and no retardation interferes with the back stroke of 13.
The staple keys on the are 13 present wedge shaped sides underneath to the point
of the escapement finger 41, in order to ensure its engagement without obstructing
the action of the escapement lever. I also prefer to round the upper sides of these
keys so that the bent point of the finger 36 can pass easily over them.
Though I have shown a call bell as the instrument, brought into action, by
completely working out the combination upon any one of the apparatus, other
known signalling instruments may be substituted for it. The apparatus described
may be applied to telegraphic or telephonic lines, but is especially adapted for
exploding torpedoes or mines in warfare. For example a number of torpedoes
being anchored in various parts of a harbour, any one of them might be exploded
by the transmission of a particular combination of impulses acting on the arc 13 of
the apparatus connected to that torpedo..
As the main line L goes only to the relay R in each case, and the exploding fuse,
which would occupy a position corresponding with that of the call bell B' (Fig. 3)
is on a different circuit and may be at a distance from the main line, the cable or
conductor might generally be recovered without being injured by the explosion.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In an electric signalling apparatus intermediate between a conducting line and a
signalling instrument, in combination with a swinging are urged in one direction
by a weight and having on it a series of keys and intervals, a set of escapement
fingers worked by an armature lever which is caused to vibrate by impulses trans-
mitted along the line in such manner that these fingers allow the are to perform
its full stroke and then make contact for operating a signal when the succession
and duration of the transmitted impulses correspond with the arrangement of the
keys on the arc, but that, when the impulses do not correspond with the keys, the
said fingers become disengaged from the arc and make another contact bringing
into action a relay whereby the arc is restored to its initial position, substantially
as and for the purposes set forth.
2. In apparatus of the kind above referred to, the construction of the swinging are
with its keys of staple form, and its combination with a rocking spindle having one
arm loaded with a weight and another arm loosely linked to tlie armature lever of
a relay magnet, and carrying a contact, substantially as described.
3. In apparatus of the kind above referred to, in combination with the keys of
staple form on the swinging arc, the upper hooked escapement finger and the lower
finger pivotted to vibrate between stops, also the spring contact arm arranged
under the fingers so as to be depressed and make contact when the upper finger
drops through an interval between the keys, substantially as described.
4. For operating apparatus such as is above referred to, a contact key or a
revolving disc or cylinder with make and break parts of its periphery in combination
with a line wire, a relay, suitable local batteries and their circuit wires, substantially
as described with reference to Fig. 3.
5. For retarding the movement in the one direction of the swinging are above

page_text: referred to, the combination with its rocking spindle of a lover having an armature
facing the pole of an electro magnet, and contacts for the circuit of the magnet
operated by the armature lever of the relay magnet, substantially as described with
reference to Fig. 8.
Dinted thin with d..
1000
ABEL & IMRAY,
Agents for the Applicant.