Improvements in Mechanical Telephones and Insulators for the same.
Year: 1886

page_text: Date of Application, 2nd July, 1886.
Complete Left, 2nd Apr., 1887.
Complete Accepted, 3rd May, 1887.
Improvements in Mechanical Telephones and Insulators for
the same.
I, WILLIAM EDGAR LEA of Runcorn in the County of Chester, Engineer, do hereby
declare the nature of this invention to be as follows:-
This invention consists in a simple form of telephonic apparatus, by which for short
lengths, under say five miles, messages and other sounds can be sent. It is especially
applicable for private lines. The transmitter and receiver are alike, and consist of
1st. A large wooden or other mouthpiece.
2nd. A diaphragm of "vulcanized fibre," or other very tough, non expansive or
non stretching material, preferably of a non-metallic type.
This can be of any
diameter to suit volume of sound required, etcetera for ordinary messages eight inches
diameter will do.
3rd. Over this diaphragm, and preferably nailed to it, is a cover preferably a bush
plate or metallic soup plate nailed through the diaphragm to the (wooden) mouth
piece, or otherwise fixed in place. It has a wide hole at back in centre for the wire to
pass through, and is usually fastened face to the wall.
4th. A brass or other disc with projection passing through the diaphragm to which
the line wire is attached. The disc performs the double duty of a plate to tap upon,
to draw attention; a knocker plate in fact, and an abutment to hold the wire and
prevent it tearing away from the diaphragm. In order to carry the wire and prevent
it sagging down onto the bush plate, tension insulators are provided as follows; a cup
with a hole in the bottom is suspended by a wire, a block of rubber is placed in the
cup, and the suspension hook passing through the hole and the centre of the rubber is
held in position by a washer and nut at top, the line is tied to this by a wire. The
apparatus is fixed in the following manner, the receivers are each placed against a
wall or backing with a hole through it, corresponding with the central hole of the
receivers the two wires are then joined up, with the wire tightly stretched, and
supported at intervals by the insulators. If a corner has to be turned, the wire is
bent round a pulley supported on an insulator. If desirable, a line can be forked,
and both forks have a receiver, in this case, any one can be used, to talk to persons at
the other two instruments.
A
.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Patent Agents for the Applicant.

page_text: I, WILLIAM EDGAR LEA, of Runcorn in the county of Chester, 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 :-
This invention consists in a simple form of telephonic apparatus by which for short
lengths, under say five miles, messages and other sounds can be sent. It is especially
applicable for private lines. The transmitter and receiver are alike.
It is best described by aid of the accompanying drawings in which,
Figure 1 is a plan and Figure 2 a section of the telephone receiver or transmitter.
Figure 3 elevation of an ordinary insulator therefor and Figure 4 elevation of an
insulator at a bend in the wire.
"
Referring first to Figures 1 and 2. In these A is a large wooden or other mouth
piece. B is a diaphragmn of "vulcanized fibre or other very tough, non-expansive
or non-stretching material, preferably of a non-metallic type. This can be of any
diameter to suit volume of sound required, etcetera, for ordinary messages eight inches
diameter will do. The kind of material which I prefer is that known in America as
vulcanized fibre, and the manufacture of which is described, I believe in American
patents, dated November 12 1872 and June 11, 1878. I only know this latter
circumstance from seeing the material which I get from America marked with the
word patented and these dates. Over this diaphragm and preferably screwed to it is a
cover C, preferably a bush plate or metallic soup plate nailed through the diaphragm
to the (wooden) mouth piece, or otherwise fixed in place. It has a wide hole at back
in centre for the wire to pass through without touching and is usually fastened face to
the wall. D is a brass or other disc with projection passing through the diaphragm
to which the line wire is attached. The disc performs the double duty of a plate to
tap upon, to draw attention; a knocker plate in fact and an abutment to hold the wire
and prevent it tearing away from the diaphragm. In order to carry the wire and
prevent it sagging down onto the bush plate, tension insulators are provided as
follows, see Figures 3 and 4. E is a Brass or earthenware cup with a hole in the
bottom suspended by a wire F, a block of rubber G is placed in the cup and the
suspension hook H passing through the hole and the centre of the rubber is held in
position by a washer I and nut J at top. The line is preferably tied to this by a wire.
Where a bend in the wire has to be made the tension regulator instead of being
attached directly to the wire is attached to a yoke L as shown, and this is linked to
the wire by two or more links M at distances apart and of varying lengths if more
than two in number, so as to follow the line of curve of the wire.
The apparatus is fixed in the following manner, the receivers are each placed against
a wall or a backing N with a hole through it, corresponding with the central hole of

page_text: the receivers, the two wires are then joined up, with the wire tightly stretched and
supported at intervals by the insulators. If a corner has to be turned, the wire is
bent round a pulley supported on an insulator or suspended from the insulator by a
series of links as illustrated. If desirable a line can be forked, and both forks have a
receiver, in this case any one can be used to talk to persons at the other two instruments.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed, I declare that what I claim is :-
1st. The telephone receiver or transmitter as a whole, substantially as described in
Figures 1 and 2.
2nd. The insulating apparatus consisting of a cup C suspended from the support
and carrying a rubber or like non-conducting resilient block to which the wire carrier
is suspended, substantially as described.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Patent Agents for the Applicant.