Combined Telephone Switch and Ringing Key.
Year: 1892

page_text: Date of Application, 14th Oct., 1892-Accepted, 17th Dec., 1892
COMPLETE SPECIFICATION.
Combined Telephone Switch and Ringing Key.
RICHARD WHITEHEAD 7 Well Road, Heeley, Sheffield, Telephone Engineer,
ALFRED DOXEY, 7 Well Road Heeley, Sheffield, Electrical Engineer, 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:-
In conjunction with the accessory apparatus combined in a telephone set, it is
customary to use an automatic switch, & ringing key, as two distinct pieces of
mechanism. The former put in action by hanging the telephone on the hook, the
latter by pressing a button or key by hand, when desiring to call up distant
station.
The present invention has for its object, the utilisation of the telephone lever as
a ringing key, in addition to its ordinary duties as an automatic switch. The call
signal being given by pressing down the telephone lever, instead of the usual key
provided for this purpose. An application of this principle is the following
See sectional drawing where (L) represents a telephone lever provided with the
usual hook for hanging up the telephone receiver. A metal bracket (B) is securely
fixed to the wood case (W) by means of screws (S & S¹). A screw passing
through lever at (C) is threaded into fixed metal bracket (B), & serves as an axis
on which the lever may move as a centre. Two ivory insulating pieces (1 & 1¹) are
screwed into arm of lever, & by means of these, its movements are transmitted to
a spring (M) electrically connected to line terminal of instrument.
Three contact stops are provided, marked respectively (c), (d), (e), with each of
which line spring (M) may engage.
I. When telephone receiver is placed on the hook, insulating piece (1) near axis
of lever is forced against line spring (M), causing it to move in contact with
intermediate stop (d). At this point ivory bushing (1) comes in contact with line
spring (M), preventing further movement for the time being, by reason of the
latter bushing being farther from axis of lever, consequently not acting on spring
to the same advantage.
Intermediate stop (d) is electrically connected to local bell, thereby placing local
instrument in a position to receive a call signal from distant station, when telephone
is normally resting on the hook.
II. In order to call up distant station, the operator places his hand on the lever,
& forcibly presses it down. Line spring (M) now glides over & leaves intermediate
stop (d) making contact with forward stop (c) electrically connected to copper
terminal of ringing battery. "Zinc of battery is to earth as usual," consequently
a current is sent to line ringing bell at distant station.
III. When the operator's hand is removed from the lever, line spring (M)
returns to its original position by reason of its elasticity, and a call signal may now
be received.
IV. On removing telephone from the hook, line spring (M) finally flies against
back stop contact (E) connected in the usual manner to secondary circuit of
instrument, which is now in readiness for conversation.
Provision is made for the opening and closing of local speaking battery by ivory
bushing (A) engaging spring (O). On taking telephone off hook, spring (0) by
its elasticity makes contact with stop contact (P) thus closing local battery
through microphone or primary circuit. When telephone is again hung on the
hook ivory bushing (A) forces spring (0) away from contact (P) and breaks the
circuit.

page_text: NATURE OF CLAIM.
Having now particularly described & ascertained the nature of my said inven-
tion, & in what manner the same is to be performed, I declare that what I
claim is
I. An application of the telephone lever as a ringing key, in addition to its
ordinary duties as an automatic switch, dispensing with a separate key for that
purpose.
II. A telephone lever totally insulated from line, or line & battery circuits
transmitting its movements to a suitable mechanism, through the medium of.
insulating pieces. Thereby avoiding chance of shock to an operator sending a call
signal when pressing down the lever.
III. The method of attaining the object of the said invention, by providing a
suitable mechanism, as the one described in which the telephone lever engages
three contacts viz., forward, back, & intermediate.
Dated this 13th day October 1892.
RICHARD WHITEHEAD.
ALFRED DOXEY.