Improvements in and relating to Prepayment Devices for Use with Telephones.
Year: 1897

page_text: Date of Application, 20th May, 1897-Accepted, 3rd July, 1897
COMPLETE SPECIFICATION.
Improvements in and relating to Prepayment Devices for Use with
Telephones.
I, SIEGFRIED SILBERBERG, of 79 W. 118th Street, in the City and State of New
York, United States of America Merchant, 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:-
This invention relates to telephonic prepayment systems of that class in which
any person may obtain the use of a telephone at a public station by paying
a certain fee, and without the aid of an attendant at the instrument either for the
protection of the telephone company or as an assistant to the customer.
Coin operated vending devices are well known, and the same principle is car-
ried out in this invention except that instead of a coin being used to actuate the
mechanism, a key or peculiarly shaped piece of metal is used. The object in
making this substitution is to avoid placing money in public places to be a
temptation to dishonest persons to break into the box or receptacle and secure
the money. It is my intention to place the keys on sale at convenient places
where they may be obtained in any quantity by persons having use occasionally
for a telephone. In this way the key of course, becomes of value, but it is not
a legal tender, and is therefore not so tempting to dishonest persons.
By my invention, a person desiring the use of a telephone may approach
the instrument insert a key, and then ring up the central office.
If the connec-
tion desired can be obtained, the customer manipulates the apparatus to carry the
key entirely into the structure where it falls into a receptacle, upon which the
central office operator, who has been automatically notified of the fact that the
key is deposited, makes the required connection and permits conversation to be
carried on.
If the desired connection cannot be made on account of the line be-
ing busy" or for any other cause, the central office notifies the would-be
customer, and the key which has only been partially inserted into the apparatus,
may be withdrawn for use at a later time on the same or some other instrument.
The mechanism for carrying out this invention is of simple character and is
adapted to be applied directly to the casings of instruments now in use.
6.
The construction and combination of apparatus hereinafter described and
claimed constitutes this invention.
Referring to the accompanying drawings. Figure 1 represents a side elevation
of the improved apparatus, the front of the casing being removed to show the
mechanism, and a side elevation of the magneto call box of the telephone being
shown in the background.
Figure 2 is a vertical central section of the toll apparatus and a partial front
elevation of the telephone box to which it is attached.
Figure 3 illustrates a sectional view along the line of Figure 1.
Figure 4 shows a section along the line y-y. Figure 1.

page_text: а паше.
Figure 6 is a similar view of the key carriage.
Figures 7 and 8 are illustrations of the key holder with its surrounding parts,
the key being inserted in Figure 8.
Figure 9 is a plan of the key.
Figure 10 represents a diagram of the electrical circuits of the telephone
showing how the toll apparatus is inserted.
I have illustrated in the drawings a portion only of the ordinary telephone
instrument, consisting of the magneto call box A. Against one side, preferably
the right hand side, of the box I fasten in any suitable manner the casing B
enclosing the mechanism constituting my invention. The upper part of this
casing is provided with two windows, one of which discloses to view a dial b
with finger b', and the other an indicator 62 of a counting device or register. In
the lower front part of the case B a cylindrical key holder c provided with a
keyholder c', is mounted to oscillate in a barrel fixed in the casing. This key-
holder carries a bolt c which normally projects into a notch in the barrel to
prevent the oscillation of the holder. This bolt is provided with a projection c
passing into the keyway and adapted to be engaged by the key to lift the bolt
out of the notch and permit of the oscillation of the keyholder.
At A is shown the end of the shaft of the magneto instrument upon which is
usually fastened the crank by which the central office is rung up. In applying
my invention the crank is removed from the end of this shaft and is applied to the
outer projecting end of the main shaft d of my apparatus, this main shaft being
in alignment with and practically forming an extension of the shaft A. The
crank is represented by d. Upon the end of the shaft A' is rigidly fixed a large
wheel e with its periphery provided with well defined notches e and with its hub
formed on its outer face or provided with one member of a suitable clutch, the
other member of which is on the abutting end of the shaft d. The teeth or
other equivalent parts of the clutch are so arranged that when the shaft dis
turned to the right, or in the usual direction for ringing up the central office,
the parts of the clutch will engage and the magneto will be operated. The main
shaft d is mounted in a frame f shown in perspective in Figure 5 and consisting
of two upright parts fl and f, the latter having an extension f³ with a dovetailed
track or groove f, which will be described hereinafter. The part of the clutch
is keyed to the shaft, but adapted to slide longitudinally thereon; it is constantly
forced towards the member by a spring e surrounding the shaft and located
between the frame f¹ and the clutch member . Between the members fl and f
of the frame the shaft carries a loose pinion g having upon its inner face a clutch
member adapted to engage with a corresponding member which is keyed to
the shaft, but adapted to slide thereon, and which is held against g by the spring 4
g. The teeth of this clutch are opposed to those of the clutch e², e, so that when
it is locked or gripped, the other is unlocked and sliding, hence, from the above
description, it will be understood that the clutch g', glocks and carries the pinion
with the shaft only when the crank is turned to the left, or in the reverse
direction to that used when ringing up.
4
In the guide f' is placed the carriage shown in Figure 6. This carriage is
provided with a projection h fitting into the dovetailed groove and adapted to
slide therein, and, in addition, is furnished with a rack engaging with the
pinion g, so that the rotation of the latter causes the carriage to slide in its guide
way. The pinion, however, can be turned in only one direction by the shaft, and 5
to provide for the return movement of the carriage, I pass a rod h² through a
longitudinal hole 3 in the carriage and insert a spring between one end of the
rod and one end of the carriage. The movement of the carriage under the action
of the pinion compresses the spring, and when the pinion is released the spring
returns the carriage to its normal position as shown in Figure 1. The key used 5
consists of a flat metal plate shown in Figure 9 and letterd K, provided near its for-
ward end with two rectangular notches k, k located opposite to each other and

page_text: having along one face a cam groove kl. This groove commences at the forward
extremity of the key and midway between the edges, and gradually curves
toward one edge as it runs to the rear of the key. The carriage before described is
provided wth two lugs 5 and 6 which are located directly at the back of the
5 keyholder with an opening between them in line with the keyhole e¹. When
the key is inserted through the key hole, it passes through the opening between
these two lugs, until the two notches are in the same plane with the lugs
at which time the key may be rotated, the narrow part of the key
between the notches just fitting between the lugs as shown in Figure 3. When
the key is in this position, however, it cannot be withdrawn or forced inward by
pushing or pulling the key itself, because the lugs will engage with the shoulders
of the notches and prevent such movements. The cylindrical key holder is
provided, inside the case, with a radial finger 6 which projects into an elongated
opening in the bolt i. This bolt is suitably supported transversely of the case
in loops 2, and carries at one end an angular projection engaging with one of
the notches in the wheel e and preventing its rotation. The bolt is held in this
position by the spring it.
In the back of the case is mounted a heavy vertical rod J preferably square in
in cross section and having a rack j on one of its corners. The lower end of this
rod is stepped in a slit tube j' which acts as a guide for the rod.
In the upper
part of the casing is a train of clock work M with one of the wheels of which the
rack is in engagement. The rod carries a metallic strip which is a little longer
than the length of the stroke of the rod and is electrically insulated from the rod
This strip has two projections and I, adapted to make contact with a fixed
finger as the rod rises and falls in the manner hereinafter described. The
extreme upper end of the rod is provided with a lug which, when the rod is
carried to the extremity of its upward stroke strikes a finger and turns the
counting and registration mechanism & one point or notch. The rod is elevated
by means of a curved lever o pivotted at the joint o and connected with the rod
by means of links pivotted to trunnions on the rod, the lever being forked
at the end to straddle the rod when it moves upward. The 'opposite end of the
lever projects downwards to a point directly opposite the keyway and
immediately behind the lugs h, h on the carriage, as shown in Figure 1. It
is formed with a right angled notch of having a vertical side against which the
end of the key is adapted to strike, and a horizontal side under which the end of
the key is adapted to rest.
In Figure 10 a diagram of the ordinary telephone circuits is shown, the main
line being indicated by wires w and w¹. Across the two wires, and shunting the
telephone apparatus, is a circuit containing a battery phaving one of its
terminals connected to the contact finger and the other by means of a flexible
connection with the insulated strip 7. Thus when the lugs make contact
with the finger 12 an impulse is sent over the main line from battery 2 to the
central station which may be indicated there by the ringing of a bell or operation of
any other suitable annunciator. In the bottom of the casing B a suitable
receptacle B is provided into which the keys K fall and are retained until
removed by an authorised person who opens the receptacle by releasing the lock B².
The operation of the mechanism is as follows. A person desiring the use of the
telephone first provides himself with a key which he may obtain at a drug store,
barber's shop, or other more or less public place by paying ten or fifteen cents er
whatever the toll for an ordinary conversation may be. He passes the key into
the key hole c¹ until it is stopped by the end of the lever o, the key then being
in the same vertical plane as the end of the lever. When the cam groove k¹ en-
gages with the lug e the latter immediately begins to rise with the further progress
of the key, until the bolt is entirely free of the notch c. He then gives the key
a quarter turn and entraps it by reason of the engagement of the lugs h and he
with the notches ; at the same time he forces the key a little further in to send
its forward end beneath the horizontal shoulder on the extremity of the lever o.

page_text: This rotary movement of the key carries with it the key holder c, and through
the finger throws the bolt i out of engagement with the wheel e.
He may
then let go of the key, leaving it projecting partially out of the case, the end of
the lever o meanwhile preventing the backward rotation of the key under the
action of the spring . The magneto shaft now being released, the customer
tings up the central office by turning the crank to the right, the motion being
transmitted through the clutch e, e. while the clutch y¹, g2 slips. If the central
operator can make the desired connection the customer is told to go ahead. He
then rotates the crank in the opposite direction which causes the clutch e, e
to slip and the clutch g', to lock and rotate the piston g. The carriage there-
fore begins to travel towards the rear of the case and the key is drawn into the
case by reason of the engagement of lugs hand h. The key in pushing against
the end of lever o swings that lever into the position shown in dotted lines in
Figure 1, lifting the rod J to the upper limit of its stroke, and the key, being
carried free of the keyholder c, falls into the receptacle B¹. As the rod J move
upwards two impulses from the battery p₁ are sent in rapid succession to the
central office and serve as a notification to the operator there that the key has
been deposited in the case. The operator then completes the connection between
the customer and the person for whom he has called, and they commence their
conversation. At the moment the rod J reaches the upper end of its stroke, the
lug operates the register and then the rod immediately commences to fall by its
own weight, but is retarded by the clock train. This train is constructed to limit
the period during which the customer shall use the instrument. If, for instance,
one key permits a customer to have conversation for three minutes, the rod will
fall in just three minutes, the fractions thereof being indicated by the index bl.
In falling, the circuit of the battery is closed twice, but this time, at an interval
of three minutes. When the central operator gets the second signal, she is at
liberty to cut off the conversation or permit the conversing parties to hurriedly
terminate their conversation.
As soon as the key is deposited the customer releases the handle and the
spring returns the carriage to its normal position, the boit i having meanwhile
gone to its normal position and locked the wheel e, thus making all parts ready
for another customer.
If, after ringing up the central office, the would-be customer finds he cannot
get the desired connection, he first slightly withdraws the key to release it from
the end of the lever and then rotates it backwards a quarter turn to carry the
notches out of engagement with the lugs and 6. He can then withdraw the
key and use it at any later time upon the same or another instrument.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is —
1. The combination with the calling instrument shaft of a telephone, of a
notched wheel mounted thereon, a bolt adapted to engage the notches of the said
wheel, an oscillatory key holder engaging with the said bolt and means whereby
a key may oscillate the said holder to release the said shaft, substantially as set forth
and as illustrated by the accompanying drawings.
2. The combination with the call instrument shaft of a telephone, of a notched
wheel mounted thereon, a bolt adapted to engage the notches of the wheel, an
oscillatory keyholder engaging with the bolt, a lock for the keyholder, and means
for releasing the holder and oscillating it to release the said shaft, substantially
as described and as illustrated by the accompanying drawings.
3. In a telephone toll apparatus, a main shaft provided with two clutches, one
connecting it with the calling apparatus and operative when the shaft is turned
in one direction only, and the other connecting it with the key carriage and
operative when the shaft is turned in the opposite direction, substantially as
described and as illustrated by the accompanying drawings.

page_text: 4. In a telephone toll apparatus operated by a key, the combination of a key,
a carriage with which the key engages when inserted, a shaft, and connections
between the shaft and carriage, whereby the latter is moved when the former is
rotated, substantially as described and as illustrated by the accompanying
drawings.
5. In a telephone toll apparatus operated by a key, the combination of a key
carriage with which the key engages when inserted, a shaft, connections between
the shaft and carriage whereby the latter is moved when the former is rotated,
and a clutch for disconnecting the shaft from the carriage, substantially as
described and as illustrated by the accompanying drawings.
6. In a telephone toll apparatus operated by a key, the combination of a key
holder, a key carriage, 'means for locking the carriage and key together, and
means for moving the holder to lock the key in or release it from the carriage,
substantially as described and as illustrated by the accompanying drawings.
7. In a telephone toll apparatus operated by a key, the combination of a key
holder and a key carriage adapted to engage with the key, the key holder being
adapted to oscillate to effect an engagement between the carriage and the key,
substantially as described and as illustrated by the accompanying drawings.
8. In a telephone toll apparatus operated by the insertion of a key, a main
shaft adapted to send in a call when rotated in one direction and to entrap the
key when rotated in the opposite direction, substantially as herein before
described and as illustrated by the accompanying drawings.
9. In a telephone toll apparatus operated by a key, a circuit closer, a weight
operating the same, a lever for lifting the weight and means whereby the inser-
tion of the key will enable the customer to lift the weight, substantially as
described and as illustrated by the accompanying drawings.
10. In a telephone toll apparatus operated by a key, a circuit closer, a weight
operating the same, a lever for lifting the weight, a clock train regulating the
return movement of the weight, and means whereby the insertion of a key will
enable the customer to lift the weight, substantially as described and as illustrated
by the accompanying drawings.