An Improved Coin Operated Telephone Instrument for Public Call.
Year: 1898

page_text: Date of Application, 17th Jan., 1898-Accepted, 26th Mar., 1898
COMPLETE SPECIFICATION.
An Improved Coin Operated Telephone Instrument for Public Call.
We, FREDERICK JOHN CLENDINNEN of "Haven," Williams Road, Hawksburn,
Doctor of Medicine, and GEORGE ANDREW PHILIP WEYMOUTH, of City Road, South
Melbourne, Electrical Engineer, both in the Colony of Victoria, do hereby declare
the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
The object of our invention is to provide a telephonic call box or instrument for the
use of the public. By its aid the insertion of a coin into a slot enables a non
subscriber to communicate with the exchange. Should however the required sub-
scriber be engaged the coin is not forfeited but is ejected from the machine. Our
invention which is simpler than those that have preceeded it requires no skilled
attention in its operation, is applicable to any call box and can be quickly and
economically attached with the prospect of but little derangement.
Our invention consists of a telephone call box in which there is a slot for the
reception of a suitable coin. The ringing up circuit in this is normally open but on
the entry of a suitable coin the edges of the same close it. The exchange can then
be called in the usual way. If no connection however can be obtained with the
subscriber desired the money paid for the conversation is returned.
But in order that our invention may be better understood we will now refer to the
accompanying sheet of drawings which are to be taken as part of this specification
and read herewith.
Figure 1 represents a front elevation of the mechanism which for the convenience
of illustration is shewn as attached to a rectangular piece of ebonite or other insu-
lating material. The whole mechanism with the magneto can be in one call box or
it may be situated in another box attached to existing instruments.
Figure 2 shews a side elevation in which a coin has been released from the shoot
and is falling into the cash receipt box.
Figure 3 represents a back view of Figure 1.
Figure 4 a plan of Figure 3.
Figure 5 a perspective view on a small scale of our instrument when cased in and
attached to an existing telephone box though as before said in new instruments it
can all be in one case. On the bottom of the case surrounding our instrument is
seen the cash delivery box into which the coin falls if the would be user cannot attain
his ends.
Similar letters of reference indicate similar or corresponding parts where they
occur in the several views.
On reference to the drawings it will be seen that A is the line lever of an ordinary
telephone box having a magneto and bell and to the end of which the receiver and
transmitter W is hung. Above this lever is pivotted the bell crank lever B to the
lower arm of which by an adjusting or other link is connected the spring metallic
contact face C. This forms with D the two contact sides of the coin shoot both of
which are in the ringing circuit. This circuit is closed by the entry of the coin. On

page_text: the removal of the receiver and transınitter from its lever to communicate with the
exchange the said lever being freed from its weight is by a spring E lifted. The
arm A projecting from the lever strikes the upper arm of the bell crank lever B
which releases the coin and opens the ringing circuit. The coin then falls on to a
tilting platform F where it remains till the allotted time has been spent in conversa-
tion. At the expiration of the same the hanging of the receiver and transmitter on
the line lever causes the same to descend by its arm A¹ striking the top of the
lever G. This by a link H is connected to a lever I secured to the pivot pin J upon
which the platform F is pivotted. To J is secured a threaded rod K upon which is
an adjustable weight L. So that on the completion of a conversation and the
replacement of the receiver and transınitter the platform moves outward and the
coin falls into the cash receipt box in the interior.
But if the desired subscriber is engaged the exchange sends a battery current
through a relay (not shewn in the drawings) but, which is of such a resistance as not
to interfere with the speaking circuit. From this connection is made through a
solenoid and local battery. This solenoid M has connected to its lower core Na
lever O which is pivoted to a bracket Z. So that when the desired subscriber cannot
be obtained the tilting platform by the core N and lever 0 and link Y is moved
inwardly and the coin is ejected into the box X. The upper core N1 is hung by a
spring P to an arm Q projecting from a lever R pivotted at S and having on its
moving end a resetting piece T. Connected to the top of N¹ is the lower arm of a
bell crank lever. The upper arm U by the tension of the spring is pressed against
the ebonite thereby preventing the lever R from descending. But directly the core
is drawn into the solenoid the upper arm U is removed from beneath R and the latter
falls upon the stop V making contact therewith. The lever R is lifted and the arm
placed again beneath it by the lifting of the receiver and transmitter from the line
lever.
Should the exchange desire to ring up the proprietors of the shop or office in which
the call box is located it is accomplished by sending a battery current along the line
and through the aforesaid relay. This connects the local battery and solenoid and
withdrawing the arm U from beneath R allows the latter to fall onto V. The ringing
circuit is thereby completed. The removal of the receiver and transmitter from the
line lever causes the said lever to be raised by its spring and also resets the said
lever and arm and once more opens the ringing circuit.
If the exchange informs a person who has prepaid that the subscriber or other to
whom he wishes to speak is engaged the receiver and transmitter must not be placed
on its hook on the line lever until the coin is ejected. When once the coin is paid
the conversation must either be obtained or the coin returned before the receiver
and transmitter is hung.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1st. An improved coin operated telephone instrument for public call consisting of
a relay and a solenoid operating a tilting platform beneath the coin shoot all
as and for the purposes hereinbefore described and as illustrated in the
drawings.
2nd. An improved coin operated telephone instrument for public call having the
ringing circuit closed by the entry of a coin or by a battery current from the exchange
all as and for the purposes herein before described.
3rd. An improved coin operated telephone instrument for public call having
beneath the coin shoot a tilting platform which by the replacement of the receiver
and transmitter on its line lever discharges the coin into the cash receipt box
or on a battery current from the exchange through a relay and sole-
noid repays the said coin all as and for the purposes herein before described.
4th. An improved coin operated telephone instrument for public call consisting
of a coin shoot below which is a tilting platform retained vertically by a balance

page_text: weight and pivotted in bearings, said table being moved forwardly by a lever, and a
link attached to a lever moved by an arm on the line lever and moved backwardly
by a battery current which from the exchange and through a relay draws into a
solenoid a lower core attached to a lever having a link thereon connected to a lever
on the platform pivot pin or spindle all as and for the purposes berein before described
and as illustrated in the drawings.
5th. An improved coin operated telephone instrument for public call in which the
ringing circuit is closed by a battery current from the exchange passing through a
relay and a solenoid the upper core of which draws downwardly a bell crank lever
thereby releasing a lever which falls upon a stop and completes the circuit all as and
for the purposes herein before described.
6th. The combination and arrangement of the whole of the parts as hereinbefore
described and as illustrated in Figures 1, 2, 3, 4 and 5 of the accompanying
drawings and constituting our "Improved Coin Operated Telephone Instrument
for Public Call."
...
W. P. THOMPSON & Co.,
322, High Holborn, London, W.C., Patent Agents for the Applicant.