Electrical Apparatus for Raising the Shutters of Telephone Indicators.
Year: 1893

page_text: Date of Application, 2nd May, 1893
Complete Specification Left, 1st Feb., 1894-Accepted, 3rd Mar., 1894
PROVISIONAL SPECIFICATION.
[Communicated from abroad by SoCIÉTÉ GÉNÉRALE DES TÉLÉPHONES (Reseaux
Téléphoniques et Constructions Électriques), of 41, Rue Caumartin, Paris,
. France, Manufacturers.]
Electrical Apparatus for Raising the Shutters of Telephone
Indicators.
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery
Lane, in the County of London, Chartered Patent Agent, do hereby declare the
nature of this invention to be as follows:-
This invention relates to means of electrically raising the shutters of the indicators
employed in telephone exchanges.
For each subscriber, as is well known, there is an indicator, by the fall of the shutter
of which, the operator is informed of the subscriber who calls, and it is the business of
the operator, when thus informed, to close the shutter and make communication with
the subscriber. According to the present invention the closing of the shutter is
effected, not by the hand of the operator, but electrically, in the following manner.
On the hinge of each shutter is fitted, free to revolve, a pulley from which a chain
or cord passes to the core of a solenoid, which is held back by a spring. By means
of a stud on the pulley under the fallen shutter, the shutter is raised when the
solenoid is excited by an electric current, which is transmitted to it.in the following
manner-
Immediately under the spring jack of each subscriber there is an insulated metal
block having in it a plunger pressed forwards by a spring. When the operator is
called, and sees by the fall of a shutter which subscriber calls him, before inserting
his plug in the jack of the subscriber, he inserts it in the block below, pushing in the
plunger till it makes a contact by which the solenoid belonging to the fallen shutter
is put in circuit with the battery.
+
'
The core of the solenoid (which preferably is mounted on rollers when the
solenoid is horizontal) being attracted, causes the pulley to make a partial revolution,
by which the shutter is raised to the position where it is held by the usual catch.
When there are indicators to shew that subscribers have ended their conversation,
the shutters of these are raised by similar means.
Dated this 2nd day of May 1893.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Electrical Apparatus for Raising the Shutters. of Telephone
Indicators.
1, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane,
in the County of London, Chartered Patent Agent, 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 means of electrically moving the shutters of the
indicators employed in telephone exchanges.
For each subscriber, as is well known, there is an indicator, by the fall of the
shutter of which, the operator is informed of the subscriber, who calls, and it is the

page_text: business of the operator, when thus informed, to close the shutter and make
communication with the subscriber. According to the present invention the closing
of the shutter is effected, not by the hand of the operator, but electrically, as
shall describe referring to the accompanying drawings.
Fig. 1 is an elevation of an indicator shutter furnished with appliances' for
raising it electrically.
Fig. 2 is a side view shewing together the two indicators of a subscriber, that is
to say the call indicator which is the higher, and the indicator for the end of the
conversation which is below.
The shutter is hinged to the plate e by a pin b in the two parts cel of the plate e
which is fixed on the front plate X, and free in the parts ff of the shutter i. A
grooved pulley h on which is wound a small chain is mounted on the pin 6 free to
turn thereon but held in position by the conical head of the pin. This pulley has
a stud which forms a stop against the plate X when the shutter falls, and
another stud (Figs. 1 and 2) which serves to raise the shutter i. The action of
the chain which passes over the small pulley h, an action which causes the raising
of the shutter, is produced electrically by means of solenoids which may be
arranged horizontally or vertically. The horizontal arrangement is preferable as
being more simple and less inconvenient, and yet all parts of the system can easily
be dismounted; as will be seen, the solenoids are independent of one another, so
that any one can be replaced if required without touching the others.
Fig. 2 shews the arrangement with horizontal solenoids.
Each call indicator A and each stop indicator A' has a corresponding sole-
noid S and S¹ one being shewn separately in section by Fig. 3 and in end view by
Fig. 4; it has a central copper tube B which serves as guide to the soft iron core C.
This core, shewn separately in plan by Fig 6, and in transverse section Fig. 7 is
arranged as a carriage having two soft iron rollers D D' held in forks E E cut in
the soft iron of the core.
To the core C is attached by a pin g the chain x, the other end of which after
passing round the pulley h.is attached to an opposing spring F, which is attached
to an adjusting screw G passing freely through holes of the plates or support HH',
so that the spring F can be strained more or less by turning the nut I. The small
screw (see the end view Fig. 5) serves to fix the adjusting screw G.
The-current is sent into the solenoid S of the indicator shutter which has to be
raised by means of keys within reach of the operator's hand.
Figs. 8 and 9 shew. this arrangement in transverse section and in plan. It consists
of a band V of ivorine in which are imbedded and fixed by screws copper
dowels m to each of which are soldered two spring blades o o also imbedded in the
ivorine. To the springs o is fixed by screws vol a copper block J, through a hole
in which slides a metal rod p integral with a plunger q which can slide in the
dowel m.
The exterior face of g is hollowed at a to the same shape as the end of the
spring jack plug r. A helical springs surrounds the rod p.
The end of p stops against a screw u lodged in a copper piece K. These
copper pieces are also imbedded in the ivorine. On each piece K are screwed two
bent blade springs y y'. The spring blades o and y extend between two spring
blades z 2 in the connecting band L, and it is to these blades that the conductors
for the battery and the solenoid are soldered.
Each band V holds as many dowels m as there are spring jacks in a band of the
same size. To each spring jack corresponds a dowel m, two springs o, a plunger q
and p, a block J, a block K and two springs y y'. The thickness of the band is the
same as that for the spring jacks.
The action is as follows:-
I
When a subscriber causes the shutter of his indicator to fall, the operator, before
inserting the plug in this subscriber's jack to answer him, pushes the plug into the
dowel m, forcing back q and causing p to come in contact with the screw u and so
close the circuit of the solenoid which operates to raise the shutter. The

page_text: operator then withdraws the plug and inserts it in the subcriber's jack immediately
above.
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. Electrical apparatus for raising the shutters of telephone indicators,
constructed and operating substantially as described with reference to the
accompanying drawings.
2. In combination with each shutter a pulley with a stud for stopping it and with a
stud for raising the shutter, a chain with adjustable spring and a solenoid having
its core attached to the chain, substantially as described.
3. The construction of solenoid core with antifriction rollers, substantially as
described with reference to Figs. 3, 6 and 7.
4. The contact apparatus for closing the circuit of the solenoid by insertion of
plug substantially as described with reference to Figs. 8 and 9.
Dated this 1st day of Feburary 1894.
ABEL & IMRAY,
Agents for the Applicant.