An Improved Sound-conveying Tube or Mouthpiece for Telephonic Instruments.
Year: 1888

page_text: Date of Application, 21st Dec.. 1888
Complete Specification Left, 11th Mar., 1889
Complete Specification Accepted. 13th Apr., 1889
PROVISIONAL SPECIFICATION.
An Improved Sound-conveying Tube or Mouthpiece for Telephonic
Instruments.
We HENRY JAMES SAYER and ARTHUR EDWARD SAYER of 47 Ludgate Hill
Birmingham in the County of Warwick Metal Merchants do hereby declare the
nature of this invention to be as follows:-
The Invention, which is constructed throughout of Brass and other Metal, consists
of a conical tube or Cylinder, the diameter of which tapers from three and a quarter
inches or thereabouts at its mouth or widest part to one inch or thereabouts at its
extremity or narrowest part; the small end of the tube is without external addition
or ornament and fits into the circular opening or mouthpiece of the Telephonic
Instrument. The mouth of the tube is fitted with a bell-shaped polished or silver-
plated rim or resonator which opens outwardly like the mouth of a trumpet; the
inside of the tube is fitted with two thin annular flanges or circular diaphragms
with central apertures the inner rinis of which are inclined at an angle of about
forty five degrees away from the mouth of the tube the inside of the small end
or extremity of the tube is fitted with a loose spiral coil of metal wire. A
moveable. V shaped Suspender of soft metal wire with a foot or claw at each free
end is fixed to the tube by a hinge attachment for the purpose of suspending the
tube to the box of the Telephonic instrument.
The purpose for which the apparatus was designed and invented is to form a mouth
piece or voice-receiver for Telephonic instruments. Ty the construction and com-
bination of the parts and the nature of the metals use'l the sound-waves are collected,
their retrogression prevented and they are impinged in a concentrated forum on the
receiving disc of the Telephonic instrument and the articulation of the speaker is thus
conveyed in a manner much more clear and distinct than when this apparatus is
not used.
Dated this 20th Drambon 1888

page_text: COMPLETE SPECIFICATION.
An Improved Sound-conveying Tube or Mouthpiece for Telephonic
Instruments.
We HENRY JAMES SAYER and ARTHUR EDWARD SAYER of 47 Ludgate Hill
Birmingham in the County of Warwick Metal Merchants 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:―
The Invention consists of an instrument or apparatus to be attached to and used in
conjunction with Telephonic instruments for the purpose of receiving and aiding the
audible transmission of spoken sounds. By its use voice articulations are economised
developed and intensified so that messages delivered in a low tone of voice or in
whispers are transmitted through Telephonic instruments with greater clearness and
distinctness than loudly-spokon messages usually are without it. Shouting is thus
obviated and liability to mistakes diminished.
The Voice-Receiver is in shape a trumpet-mouthed conical tube or funnel with
hooked clips or suspenders as shown in Figure 1.
It consists of six parts namely
A. The Conical Tube or Funnel.
B. The trumpet-shaped mouth piece or bell reflector.
C. C. The diaphragms or sound reflectors.
D. The spiral coil or intensity coil.
E. The suspender or suspenders.
F. The eye-attachment for the suspender.
All the parts are constructed of metal and are combined to form the instrument in
the way shown in the sectional drawing figure 2.
The construction of the parts is as follows:-
The Conical Tube or Funnel (A) is made of Brass rolled to the thickness of one
fortieth of an inch or thereabouts and wrought or moulded into the requisite tapering
form and soldered or brazed at the seam in the manner usual in making brass tubes.
The length of the funnel may vary from three to eight inches, and the width at the
month may vary from three inches or less to six inches or more but it is essential
that the tube should taper and its diameter gradually diminish from the mouth to
the extremity and that the diameter at the extremity or small end should be about
one inch so as to be capable of fitting into the diaphragm of the Telephonic instrument
with which the Receiver is used. The most convenient size for the Tube would be:-
length about Five inches; Diameter at mouth, about three inches; Diameter at
oxtremity about one inch.
These are the measurements shown in the Drawings where the Instrument is
represented full size. The Tube is left open at each end and may be japanned,
painted, polished or ornamented in any suitable manner.

page_text: Partly let into the tube and soldered to the rim of its orifice is a mouth-piece (B.)
which expands or opens outward like the mouth of a trumpet.
This mouth-piece or bell-reflector is spun out of rolled copper or other suitable
metal the external rim being turned or curled back on itself and the inner rim
projecting down the mouth of the tube whose diameter it narrows as shown in the
sectional drawing Figure 2.
At a distance of about one inch down the throat of the tube is soldered a conical
diaphragm or dise of brass (C.) which extends into the cavity of the funnel to the
extent of about half an inch all round and is inclined down the tube at an angle of
about Forty five degrees.
About one and a half inches further down the tube is soldered another diaphragm
or disc of brass (C) somewhat similar in size shape and slope to that lastly described
but necessarily smaller in circumference.
Should the instrument be made of a greater length than Five inches then the
number of diaphragins may be increased in proportion.
The remaining part of the interior of the tube is fitted with a spiral coil of
wire (D.) of about Seventeen Birmingham Wire Guage. The wire is made of
copper or other metal of high conductivity, it is about five inches in length and
is twisted or coiled three or four times-one end is soldered to the inside of the
tube near to the last mentioned diaphragm and the other end is loose.
Should the instrument be made of larger size than shown in the Drawing then the
spiral coil may be lengthened in proportion.
AV shaped movable suspender (E) of soft round or square metal wire bent and
hooked at the ends is affixed to the outside of the tube by a metal loop or eye-
attachment (F.) Being made of soft metal wire the suspender may without injury
be opened or bent in order to fit various sized Telephone Boxes or instruments.
The object and use of the various parts are as follows:-
The tube or funnel receives and conveys the sound waves and by its conical shape
concentrates them and prevents their lateral dispersion.
The object of the bell reflector is threefold it widens the orifice of the funnel,
forms an ornamental mouth-piece, and by its inner rim prevents the retrogression and
assists the propulsion of sounds spoken into the instrument.
The object of the diaphragms is also to prevent the return or retrogression of
sounds committed to the Receiver and by their position conformation and structure
to compel the sound waves to continue their forward movement in the direction of
the receiving disc of the Telephonic instrument.
The object of the metal coil is to give the sound waves a movement both onward
and rotary to diminish the jarring sounds which otherwise are heard and to impart
greater intensity and resonance to voice-articulations.
The object of all the parts so combined in the order indicated and composed of the
aforesaid metals is to prevent all return dispersion and loss of sound to economise,
focus and develope the sound waves and to impart to them a rotary and onward
movement together with a clear and metallic resonance and finally to impinge them
in a concentrated form upon the receiving disc or conducting medium of the
Telephonic instrument with which this apparatus may be used.
The object of the Suspender is to affix the apparatus to a Telephonic Instrument.
The suspender is provided with books or claws at its fore ends which are contrived to
catch hold of the beaded edge of the top of the Telephonic box, and when the narrow
end of the tube is inserted into the diaphragm of the Telephouic instrument the
apparatus is in a position to be used and is removable at will.
Having now particularly described and ascertained the nature of our said Inven-
ion and in what manner the same is to be used or performed we declare that
what we claim is :-
1. The use of a conical tube for the purpose of receiving concentrating and trans-
mitting sound waves or voice articulations as herein described and set forth.
2. The use of brass in the construction of the said tube as herein set forth.

page_text: 3. The use or adaptation of a trumpet shaped mouth-piece at the orifice of the tube
as herein described and set forth.
4. The use of metal diaphragms as sound reflectors or propellers as herein described
and set forth.
5. The use of a metal coil to intensify the sound and distinctness to the articulation
and to diminish jarring as herein described and set forth.
6. The use of flexible and adjustable Suspenders which in a simple yet efficient
manner fix the apparatus in the position for use as herein described.
7. The combination of all or any of the above parts with the object of increasing
the voice conducting capabilities of Telephonic instruments as herein described and
set forth.
8. The use and application of brass copper and other suitable metals for all or any
of the parts or purposes aforesaid.
Lastly. The improvements in the construction and arrangement of Voice Receivers
for Telephonic instruments as herein described and set forth in the drawings annexed
hereto.
HENRY J. SAYER.
ARTHUR EDWARD SAYER.