Improvements in Telephones.
Year: 1891

page_text: Date of Application, 25th Feb., 1891-Accepted, 9th May 1891
COMPLETE SPECIFICATION.
Improvements in Telephones.
I PARNELL RABBIDGE of York Street Sydney in the Colony of New South
Wales Electrician 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 improvements in telephonic apparatus and its aim is to
combine in an instrument of a small and compact form, the microphone, switches,
call and telephone and to obviate the necessity of unhooking or detaching any
part of the instrument when in use; composing a combination which is durable and
reliable and may advantageously be used in the place of speaking tubes or house
bells as well as ordinary telephones.
The essential feature of my invention is the manner in which I accomplish the
operation of ringing up the telephone place with which it is desired to communicate
(which I will herein call the B station) by which operation the ringing circuit is
switched off and the speaking circuit is switched on when the instrument at
the B station is manipulated in a similar manner to that at the ringing up place
(which I will herein call the A station). This is done in the following manner.
The receiver is attached to one end of a support flexible or otherwise the other
end of which is attached to the switching arrangement in such a way that by
raising the receiver the current is switched on and rings the bell or call at
the B station and when the receiver at the B station is raised the ringing circuit is
switched off and the speaking circuit is switched on and speaking communication
is established. When the receivers are dropped at the A. and B station the current
is switched off and the battery is at rest. Thus it will be seen that the support
between the receiver and the switch arrangement is the main thing in my invention.
Though the arrangement of switches, contacts receiver-supports and other parts of
the instrument may be varied to suit space or convenience.
I will now fully describe one method how I may advantageously arrange the
switches, contacts and other parts and how by means of same I accomplish my
object.
I annex drawings to which I will refer as per numbers and lettering in same.
Figure 1 is a sectional view of the combination showing the respective positions
of the transmitter, switches, contacts electro-magnet actuating the armature (which
carries the bell hammer) and the bell all enclosed in the same receptacle.
Figure 1 shows the relative position of the receiver to Figure 1 the support
attached to the receiver, and the switch arrangement.
Figure 2 is a diagram of the arrangement of switches springs and other parts
regulating the various contact makers (at the bottom of the transmitter
compartment).
Figures 24 and 2B show the relative position of the receivers to Figure 2 (the
receiver in Figure 2B is shown in section).
Figure 3 illustrates the position (on the other side of the transformer compart-
ment) of the electro-magnet, the armature and the beil hammer.
Figure 4 shows the relative position of the contact points from the one to the
other of which the current may be switched as described below.
Figures 4 and 4B show the switch spring which switches the current from the
one contact point to the other.
Figure 5 shows the collar for the spindle (fully shown in Figure 2 and marked g)
to which the one end of the receiver carrying support is attached.
a is the containing case and the cover of same with the mouthpiece; c is a
partition dividing a into two compartments, a b and c are made of insulating
material.

page_text: C
On the side of c farthest away from I place the electro magnet à inside the
bell (as shown in Figures 1 and 3) this is my call or ringing contrivance. On the
other side of I attach two collars m (as shewn in Figures 2 and 5) through which
I put a metallic spindle (Figure 2). To the end of I attach the end of the
support to the other end off I attach the receiver ! (as shewn in Figures 1A, 2A
and 2) at about the centre of the spindle I firmly attach a collar g' of some
insulating material preferably ebonite or vulcanite. This collar is round excepting
on one side, where it is made flat (as shown in Figures 1, 44 and 4B). Above the
collar is a metal spring which is at one end attached to c (as shown in
Figures 1, 2, 4 and 4) the other end of abutting between the two contact
points and (as shown in Figures 1, 4, 44 and 4B). n is a collar of some insulating
material firmly attached to the spindle and to the outside of is fixed a metal.
commutator ring n²; ² is a brush collecting off the current from '; e is a
microphone held against the diaphragm el (Figure 1).
Having now described the construction of my invention I will proceed to describe
the manner in which it may be used.
I connect the line wire to and the return wire or carth to m; and his in
contact with when at rest. is connected to the one end of the coil d; the other
end of the coil d is connected to the armature support 2 which through the
armature spring connects to contact and thence to . This is my bell or ringing
circuit. is connected through the battery to the transmitter e and thence to the
commutator ring n²; n¹ connects by means of a special insulated conductor, passing
through or alongside off, with 1, and is connected with m through ƒ and g.
This
is my speaking circuit.
In consequence of the arrangement of the circuits and the general arrangement
of springs and contacts as described, I obtain the following results-when
raising / 1 (shewn at rest in Figure 4B) at the A. station I partly revolve y to the
position shown in Figure 44 thereby bringing the spring in contact with point &
causing the bell to ring at the B station. When the receiver at the B station is
raised in a similar manner, the bell at the B station is cut out of the circuit and
speaking communication is established.
When dropping the receivers at the two
stations the current is switched off' and the battery is at rest.
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 use of a support to the one end of which the receiver is attached, whilst
the other end communicates with the switch arrangement substantially as described
and in the manner set forth.
2. The switching on and off the current by raising or lowering the receiver,
substantially as described and for the purposes as set forth.
3. The general arrangement and combination of transmitter switches, contacts,
call, and the receiver-carrying-support substantially as described and for the
purposes as set forth.
Dated this 25th day of Fal 1901
AYRTON & THOMAS,
Patent Agents.