Year: 1897

page_text: I, EDWARD PRIDDLE, Engineer, of Horsell Road Works, Highbury, in the County
of London, do hereby declare the nature of this invention to be as follows:-
This invention for improvements in telephones relates to apparatus specially
applicable in systems where a central or common battery is used for a number or
group of stations, and has for its object to produce a cheap, eflicient and thoroughly
protected apparatus.
According to this invention the transmitter, receiver and call push form
practically one cylindrical body, the receiver with the push being capable of being
removed therefrom and such removal or replacement effecting necessary alterations
of the connections.
The microphone or transmitter consists of a small carbon or similar conducting
dish or cell pivotted along a diameter on the base and in close proximity to the
microphone carbon diaphragm but with a soft felt or other separating washer so
that the granules which are placed in the cell bear evenly on the diaphragm.
This arrangement prevents any packing of the granules in the cell or dish. The
metallic axis of the dish is connected by a flexible conductor to one say the + pole
of the battery and the diaphragm through a contact spring that bears against it
and projects above the perforated protecting face of the transmitter to the line.
The cylindrical case of the transmitter is provided with two L projections pointing
inwards and one of which covers the diaphragm contact spring.
The receiver case is a metal ring with a flange that is pushed between the
L projections and thus frees the contact spring from off the microphone diaphragm
and thus also connects the receiver case, to the line wire.
The ring
contains the receiver mechanism and the call push and is screwed inter-
nally and the ear piece and push rosette are screwed in, and between them is
placed another ring which carries the magnet and coils, the various parts being
clamped between the ear piece and rosette, thus ensuring the parts being clamped
parallel to each other, and the strain being equally divided.
The push is formed in the front of the receiver, the contact spring being con-
nected to the case and thus when the receiver is in position to the line. The
spring also bears against a contact connected to the bell, the other terminal of
which is connected to the other or pole of the battery. When forced inwards
by the push the bell contact spring makes contact with another piece connected
to the first or positive pole. Either the transmitter base or case is made of
insulating material and carries the insulated terminal.
-
Dated this 5th day of V. 1907
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.

page_text: 1, EDWARD PRIDDLE, Engineer, of Horsell Road Works, Highbury, in the 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:-
This invention for improvements in telephones relates to apparatus specially a
applicable in systems where a central or common battery is used for a number or
group of stations, and has for its object to produce a cheap, efficient and thoroughly
protected apparatus.
According to this invention the transmitter, receiver and call push form
practically one cylindrical body, the receiver with the push being capable of being
removed therefrom and such removal or replacement effecting necessary alterations
of the connections.
i
The microphone or transmitter consists of a small carbon or similar connecting
dish or cell pivotted along a diameter on the base and in close proximity to the
microphone carbon diaphragm but with a soft felt or other separating washer so
that the granules which are placed in the cell bear evenly on the diaphragm.
This arrangement prevents any packing of the granules in the call or dish. The
metallic axis of the dish is connected by a flexible conductor to one say the + pole
of the battery and the diaphragm through a contact spring that bears against it
and projects above the perforated protecting face of the transmitter to the line.
The cylindrical case of the transmitter is provided with two projections pointing
inwards and one of which covers the diaphragm contact spring.
The receiver case is a metal ring with a flange that is pushed between the
projections and thus frees the contact spring from off the microphone diaphragm
and thus also connects the receiver case, which is in contact with bell, to the line
wire. The ring contains the receiver mechanism and the call push and is screwed
internally and the ear piece and push rosette are screwed in, and between them is
placed another ring which carries the magnet and coils, the various parts being
clamped between the ear piece and rosette, thus ensuring the parts being clamped
parallel to each other, and the strain being equally divided.
The push is formed in the front of the receiver, the contact spring being con-
nected to the case and thus when the receiver is in position to the line. The
spring also bears against a contact connected to the bell, the other terminal of
which is connected to the other pole of the battery. When forced inwards
by the push the bell contact spring makes contact with another piece connected
to the first or positive pole. Either the transmitter base or case is made of
insulating material and carries the insulated terminal.
-
In the accompanying sheet of illustrative drawings:-Fig. 1 is a front elevation
of the telephonic apparatus in its normal position and Fig. 2 is a side elevation
of the same.
Fig. 3 is a similar view to Fig. 1 showing the receiver and bell push
removed from the transmitting apparatus. Fig. a back elevation of the trans-
mitting apparatus. Figs. 5 and 6 are respectively front and back elevations of
the receiving apparatus, the diaphragm being removed. Fig. 7 is a sectional
side elevation of the same. Fig. 8 is a section showing the contacts of bell push.
C
The transmitter «, receiver and call push e normally form practically one
cylindrical body as shown clearly in Figs. 1 and 2. The receiver b and call push
are formed at the opposite ends of a short cylinder, provided with a flanged that fits
in and is retained behind the semicircular undercut projecting ribe on the
transmitter case: [
The microphone or transmitter comprises the outer brass case a, having the semi-
circular shaped ribe on its face and the projecting brass grating f. Secured with
the case a is a shallow ebonite or insulating dish or box g by means of strips 1

page_text: taking into notches in the dish and secured to the casing by the screws 2. Pivoted
on the bottom of the dish or box 9 is a carbon cell h which is electrically connected
through its axle and the metal strip 3 to the terminal 4 on the back of the insulat-
ing box g. On the top of the box y is shellaced or otherwise secured the carbon
disc electrically connected to the metal piece 14 on the insulating box g. The
carbon granules bear evenly and lightly against the disc . The spring contact /
also fixed on the box g normally makes contact with the piece 5 but when the
receiver is in its normal place, out of use, the flanged acts against the free end of
the contact and breaks contact with piece 5 and makes connection with the
casing of the instrument. The spring contact is connected to the line and the
metal pieces 6 and 7 on the back of the box y respectively to the bell and battery.
The receiver comprises the brass casing with its flange d. Fitting loosely
within the case b is a brass ring m having internal projections r, to which is secured
on opposite sides by the screws S the permanent magnets n. Between the
magnets on the opposite side of the case is the insulating base p. The ring is
secured in and connected with the case 6 by the screw 14.
The contact spring o is in connection with the casing m and thus with the case b
and makes contact normally with the contact piece 9 on the base 7. When fixed
inwards the contact spring breaks contact at 9 and makes contact with the piece 10
also fixed on the base p. The permanent magnet n has two poles 11 projecting
from its surface and surrounded by insulated wire coils 19 connected at one end
to the contact 12 on the base and at the other end to the contact piece 10. The
iron diaphragm s fits within the case band is attracted to the poles 11. The ebonite
ear piece screws into the end of the case containing the diaphragm and the
piece with its push button into the other end.
The connections are as follows: The contact pieces 3, 6 and 7 of the trans-
mitter are connected respectively to the contact pieces 10, 12 and 9 of the receiver.
The circuits are as follows:-In the normal position on a current being sent
into line, it passes through the spring, cases a, b, ring m, spring o, contact 9,
contact 6, and bell, thus ringing the bell. If the push c is operated the current
passes from the battery through the contacts 7, 10, spring o, ring m, cases b, a,
spring to the line.
When the receiver is taken from off the transmitter, the spring makes contact
with the piece 5 and thus with the carbon disc of the transmitter. The current
thus passes from the battery through the contact pieces 7, 9, 10 receiver coils 19
contact pieces 12, 3, through the transmitter, contact piece 5 and spring to
the line.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:-
-
1. The combined transmitter, receiver and bell push, forming normally one
cylindrical body substantially as described with reference to the drawings.
2. The combined receiver and bell push arranged at opposite ends of a ring
substantially as described with reference to the drawings.
3. The improved transmitting apparatus substantially as described with reference
to the drawings.
4. The improved receiving apparatus substantially as described with reference
to the drawings.
5. The improved microphonic contact substantially as described.
6. The improvements in telephonic apparatus substantially as described with
reference to the drawings.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.