Improvements in Hand Telephones, and in Compound Switches therefor.
Year: 1896

page_text: Date of Application, 11th May, 1896
Complete Specification Left, 11th Feb., 1897-Accepted, 3rd Apr., 1897
PROVISIONAL SPECIFICATION.
Improvements in Hand Telephones, and in Compound Switches
therefor.
We, MAX BINSWANGER, Electrician and FRANCIS GEORGE BELL Electrician,
both of No. 71 Queen Victoria Street, in the City and County of London do
hereby declare the nature of this invention to be as follows:→
Our invention relates to improvements in the arrangement of hand telephones,
and in compound switches therefor, and has for its object the simplification of the
apparatus generally.
In order that our invention may be the better understood, we have appended the
accompanying sheet of drawings in which Figure 1 is a side elevation of a form of
hand telephone shown partly in section, and with the connections shown diagram-
matically for sake of greater clearness. Figure 2 is a front elevation of the same.
Similar letters of reference indicate corresponding parts in both views.
In carrying our invention into effect we mount a transmitter T and a receiver R
upon a stalk S which may be hung up by a suitable suspender s. It is one of the
features of our invention that the suspension of the combined instruments in no
way influences the operation thereof. A rocking lever switch L is pivotted at a
within the stalk S and may be depressed at the end b, breaking contact between
the metal strip i and the pin e. Said metallic strip forms the base of the lever L,
and in the normal position of the latter, the contact between i and e is established
by the flat spring d touching both. When the end b is depressed, this contact is
broken, and contact established between the strip i and pin f also through the
spring d. When the opposite end c of the lever L is depressed, contact is broken
between i and e and established between i and the pin h. There are three line
wires, marked 1, 2 and 3. The wire leading to the battery is marked 1, and the
line wire and bell wire are respectively marked 2 and 3. The bell is distinct from
the combined instrument, and may be placed in any position relatively thereto.
The strip i upon the lever L is always connected with the line wire 2 through the
tension spring 9 and in the normal position of L said line wire 2 is connected with
the bell wire 3 through spring g strip i spring d and pin e, as shown. When the end c
of said lever L is depressed the line wire 2 is connected to the battery wire 1 by
means of the screw h. The distant bell is operated by this movement, and the normal
position of the lever L leaves the home bell circuit closed. The depression of the
end b of said lever L establishing contact between id and puts the receiver R
and the transmitter or microphone T into circuit with the line wire 2 and battery
wire 1 for the ordinary purposes of telephonic communication. In the case chosen
for illustration, we have shown a simple or direct acting instrument which may be
dapted to an ordinary electric bell for signalling purposes, and is operated
lirectly by the battery current, or primary circuit. In cases where a secondary
ircuit with an induction coil is employed the contacts id fare modified accordingly
y duplication, the action of the lever L and the operation of the instrument
emaining the same.
Dated this 20th day of Annil 190c
FREDK. WALKER,
73 St. Stephen's Road, Upton Park, London, E.,
Agent for the Applicants.

page_text: Improvements in Hand Telephones, and in Compound Switches:
therefor.
We, MAX BINSWANGER, Electrician and FRANCIS GEORGE BELL, Electrician
both of No. 71 Queen Victoria Street in the City and County of London, 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 :-
Our invention relates to certain improvements in the arrangement of hand
telephones, and in compound switches therefor, and has for its object. the simpli-
fication of the apparatus generally.
In order that our invention may be the better understood, we refer in the
description to the sheet of drawings appended to our Provisional Specification in
which Figure 1 is a side elevation of a form of hand telephone, shown partly in
section, and with the connections shown diagrammatrically for sake of greater
clearness. Figure 2 is a front elevation of the same.
Similar letters of reference indicate corresponding parts in both views.
In carrying our invention into effect we mount a transmitter T and a receiver R
upon a stalk S which may be hung up by a suitable suspender s. It is one of the
features of our invention that the suspension of the combined instruments in no
way influences the operation thereof. A rocking lever switch L is pivotted at a
within the stalk S and may be depressed at the end 6 breaking contact between
the metal strip i and the pin e. Said metallic strip forms the base of the lever L,
and in the normal position of the latter the contact between i and e is established
by the flat spring d touching both. When the end 6 is depressed, this contact is
broken, and contact established between the strip and pin f, also through the
spring d. When the opposite end c of the lever L is depressed, contact is broken
between i and e, and established between i and the pin h. There are three line
wires, marked 1, 2, and 3. The wire leading to the battery is marked 1, and the
line wire and bell wire are respectively marked 2, and 3. The bell is distinct from
the combined instrument and may be placed in any position relatively thereto.
The strip i upon the lever L is always connected with the line wire 2 through the
tension spring g and in the normal position of L said line wire 2 is connected with
the bell wire 3 through spring g, strip i, spring d, and pin e as shown. When the
end c of said lever L is depressed, the line wire 2 is connected to the battery
wire 1, by means of the screw h. The distant bell is operated by this movement,
and the normal position of the lever L leaves the home bell circuit closed. The
depression of the end 6 of said lever L establishing contact between i, d and f puts
the receiver R and the transmitter or microphone T into circuit with the line
wire 2 and battery wire 1 for the ordinary purposes of telephonic communication.
In. the case chosen for illustration we have shown a simple or direct acting
instrument, which may be adapted to an ordinary electric bell for signalling
purposes, and is operated directly by the battery current, or primary circuit.
In cases where a secondary circuit with an induction coil is employed, the
contacts i, d, fare modified accordingly, by duplication, the action of the lever L
and the operation of the instrument remaining the same.
We do not confine ourselves to the exact form of the combination hand
instrument herein described, the essential features of our invention being in the
general simplicity of the construction thereof, and the combination of parts whereby
said instrument is independent of any external switch or like apparatus.

page_text: 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:-
First. In a hand telephone the combination of parts substantially as and for the
purposes herein set forth, and shown by the appended drawings.
Second. In a hand telephone the employment of a rocking lever L, contact
strip i, springs d and g and contacts ef h connected as herein described and shown,
in combination with a receiver R and transmitter or microphone T as also described
and shown by the appended drawings.
Third. The telephone switch consisting in the lever L, pivots a and contacts d,
e, f, g, h, i, arranged substantially as berein described with reference to the
drawings.
Dated this 20th day of April 1906
FREDK. WALKER,
73 St. Stephen's Road, Upton Park, London, E.,
Agent for the Applicants.