Year: 1888

page_text: Date of Application, 17th Jan., 1888
Complete Specification Left, 5th Oct., 1888
Complete Specification Accepted, 9th Nov., 1888
I LEO EUGÈNE PERCY of 9 London Street Southwark, in the County of Surrey,
telegraph instrument maker, do hereby declare the nature of this invention to be as
follows:-
This Invention consists of a new Mouthpiece to be attached to the transmitter of
the telephone whereby the effect of the sounds which are required to be transmitted
through its agency are intensified-The apparatus comprising this new attachement is
constructed substantially in the following manner-A barrel or drum of volcanite,
brass or other suitable material of such size as to fit the transmitter of the telephone,
open at both ends and larger in the centre than at the ends, is provided internally
with a conical piece of such diameter that a small space is left between the exterior of
the said cone and the interior surface of the drum, the cone being fitted inside the
drum by means of small projections or arms at its base, and lying therein with its
base towards the telephone. The apex of this cone is thus in such a position that
the vocal or other sounds pass around it and between the surfaces of the Cone and the
drum, and the waves of sound striking the interior surface of the drum at a certain
angle, and are deflected into the transmitter of the telephone at a corresponding
angle, and condensed at a central point upon the electric diaphragm or otherwise-The
result of this arrangement is that the sounds transmitted are rendered much more
clear and distinct at the receiving end than at present, and the necessity of repeating
messages as is now the case, owing to indistinct transmission, is obviated-Vibration
is reduced to a minimum, and conversation can be carried on in almost a whisper.
Dated this Seventeenth day of January 1888.

page_text: COMPLETE SPECIFICATION.
A Mouthpiece to be Attached to the Transmitter of the Telephone.
I, LEO EUGENE PERCY of 9 London Street, Southwark in the County of Surrey,
Telegraph instrument maker, 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 :-
My invention has for its object to provide means whereby sound waves shall be con-
centrated centrally upon the diaphragm of a telephone transmitter.
In order that my invention may be the better understood I have appended the
accompanying sheet of drawings in which Figure 1 is an elevational view, and
Figure 2 is a sectional elevation of the device or appliance according to my invention.
Figure 3 is a detached elevational view of a cone to be hereinafter more particularly
described.
The device or appliance according to my invention comprises a drum or barrel
shaped mouthpiece A of metal or other suitable material, open at both ends, the
diameter of the middle portion a of which is greater than that of the ends b b¹, and is
provided with a strengthening band c which encircles the mouthpiece A at its greater
diameter a. The opening has attached thereto a hollow or recessed flange C, to
which are fixed two clamped arms D, Figure 1, to allow of the attachment of the
mouthpiece to a telephone transmitter. Within the hollow or recess of the flange C
is secured a pad or washer d (Figure 2), of any suitable pliable or resilient material
for the twofold purposes of preventing abrasion of the surface of the telephone
transmitter case, and of checking the vibration of the mouthpiece; to ensure which, a
layer of felt, cloth or other suitable material may be inserted between the clamps D,
and the case of the telephone transmitter above referred to.
Within the mouthpiece A above described is suspended upon suitable arms e a
cone E (Figures 2 and 3) of wood or other suitable material, the base of which, when
adapted to a telephone transmitter, would be opposite to and parallel with the diaphragın
thereof, the apex f of said cone being arranged centrally relatively to the opening b of
the mouthpiece A.
•
In the employment of my improved mouthpiece in conjunction with a telephone
transmitter, the action thereof is as follows, that is to say: -The sound waves, from
whatever source, entering at the opening 6, impinge upon the apex f of the cone E,
and, in their passage around, would follow a direction corresponding to the conforma-
tion of the cone, and would strike against the inner surface of the mouthpiece at a
point say at X, whence said sound waves would be diverted, and, following a direction
at an angle corresponding to that between the cone E and point a of the mouthpiece,
would meet at or near to the centre of the diaphragm of the telephone transmitter
aforesaid.
By the means above described, the sound waves, instead of being diffused over the
surface of the diaphragm of the telephone transmitter, are condensed and concentrated
upon the centre thereof, thus allowing of the conversion of sound waves into electrical

page_text: vibrations in such a manner as to ensure the transmission of verbal sound waves with
greater clearness of enunciation, and at the same time freed from the harsh vibrations
set up by the too close approximation of the loud sound waves of the human voice
upon the delicately suspended diaphragm of the telephone transmitter.
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 :-
The improved mouthpiece herein described for use in conjunction with telephone
transmitters whereby sound waves are concentrated and condensed upon the centre of
the diaphragm thereof substantially as and for the purpose set forth and shown in the
accompanying drawings.