Improvements in Apparatus for Recording and Reproducing Articulate Speech and other Sounds.
Year: 1893

page_text: Date of Application, 7th Feb., 1893
Complete Specification Left, 7th Nov., 1893-Accepted, 3rd Feb., 1894
TRUVIDIONAL SPECIFICATION.
Improvements in Apparatus for Recording and Reproducing
Articulate Speech and other Sounds.
CHARLES ADAMS-RANDALL, "Mattapoisett," 3 Woodstock Road, Bedford
Park, W., Electrical and Mechanical Engineer, do hereby declare the nature of
this invention to be as follows:-
:-
This invention relates to improvements in phonographs or speaking machines and
more particularly relates to that class of apparatus in which the material used for
making the sound-record upon, or for containing the sound-record, is in the form
of a ribbon or tape, and the invention has for its object, the improved construction
of this class of apparatus and the material used therewith, with a view to
simplification, convenience of use and improved results.
To this end the invention consists generally of a suitable base or table, to which
is secured a frame, standard or support that carries the operative parts, such as, &
rotating supporting-roller or drum over and upon which the material in ribbon-
form is carried, such roller being fixed upon a shaft or bearing driven manually or
automatically, means being provided for drawing the material through the machine,
with means for automatically rewinding the same as it is passed through the
machine. Suitable guides for guiding the material, and a reel or reels or a roller
or rollers for supporting or carrying the material in the ribbon or tape-form or in
bands, together with new and novel devices for recording articulate speech and
other sounds upon the material, and means for reproducing such recorded sounds
are provided.
The invention also particularly consists of special means for holding and
dampening the diaphragm or vibrator, and in the arrangement of the vibrator and
the parts acting in unison therewith.
The invention further consists of special and novel means for supporting the
recording or reproducing point or points independently of and detached from the
diaphragm and in the method of supporting such parts upon a fixture separate from
and independent of the frame or standard carrying the moving or rotating parts.
The devices preferably used by me for recording and reproducing speech and
other sounds, hereinbefore referred to, consist generally of a swinging or adjust-
able arm, arranged over the material, containing, or for receiving the sound-record,
such arm having a recess or chamber formed therein or thereon, over or within
which the diaphragm is held by means of a ring of metal or other material
bearing upon the diaphragm at its edge, said ring being held in place by
adjustable spring fingers or arms, secured upon the apparatus, the free ends of
same resting upon the ring.
The diaphragm, or vibrator used, is preferably made from thin steel, or very
hard aluminium of proper thickness, tension being put upon the diaphragm, by
means of the adjustable spring-fingers that hold the ring in place.. I sometimes
use, to insure the proper stiffness or tension of the diaphragm, without putting
stress or set upon the same, a circular non-metallic piece of vulcanite or celluloid or
similar material, having a diameter of about of that of the free diameter, of the
diaphragm, and about 6'4 or more in thickness, such circular piece being secured to
the diaphragm with glue, cement or similarly.
The recording or reproducing point or points are supported upon a flat spring of
proper stiffness, preferably held upon the swinging arm carrying the diaphragm,
one end of said spring being fixed, the opposite end being loosely held in place, the
flat spring passing under or across the diaphragm means being provided for

page_text: adjusting the diaphragm and spring into proper normal contact with each other. In
the reproduction of sounds I preferably use a bell-mouthed horn or trumpet of
aluminium.
.
That the vibration, jarring, friction or noises made by the moving or rotating
parts when in operation may not be transmitted through the diaphragm and the
sound-conveying tubes or trumpet, to the ear, I sometimes mount the vibrator or
diaphragm and the operative parts acting in unison therewith, upon a fixture or
standard separate from and independent of the frame or standard carrying the
moving or rotating parts.
The material used in the recording of speech and other sounds is of great
importance and I have found that with a suitable metallic alloy of two or more
metals, such as lead and tin, or lead, tin and aluminium or lead, bismuth and
aluminium, I have been enabled to get much better results than in the use of a
metal-foil having but a single element, and I preferably use the same.
February 20th 1893.
==
CHARLES ADAMS-RANDALL.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Recording and Reproducing
Articulate Speech and other Sounds.
I, CHARLES ADAMS-RANDALL, "Mattapoisett," No. 3, Woodstock Road,
Bedford Park, W. London, Electrical and Mechanical 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 :-
My invention relates to apparatus for recording and reproducing articulate speech
and other sounds, and is chiefly designed to simplify and improve the construction
and increase the efficiency and usefulness of the apparatus described in the
Specification of former Letters Patent granted to me and dated 18th June 1891,
No. 10,357.
One important feature of my said invention is the combination with the diaphragm,
which I preferably form of thin sheet steel or very hard aluminium or other suitable
metal, of an adjustable tension-regulator which exerts a variable pressure upon the
diaphragm between the centre and the circumference thereof. This tension-regulator
preferably comprises spring fingers or arms and an adjusting-device for regulating
the pressure exerted upon the diaphragm thereby. The said spring fingers or arms
bear directly upon the said diaphragm and retain the same in its seat. I prefer,
however, to employ a loose ring or annular piece which bears against the diaphragm
and is held against the same by an elastic tension device, serving also as a means of
dampening or varying the set or stiffness of the said diaphragm. In some cases,
however, accomplish this result by attaching to the centre of the diaphragm a
circular piece of vulcanite, celluloid or other suitable non-metallic material, having
a diameter equal to about one-third of that of the free diameter of the diaphragm
and about one sixty-fourth of an inch or more in thickness, the said circular piece of
material being attached to the diaphragm in any convenient manner.
My said invention, moreover, comprises other improvements hereinafter set
forth.
In the accompanying drawing I have shown how my said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a front elevation, partly in vertical section, showing one form of my
improved instrument.
Figure 2 is a rear elevation of the same, and
Figure 3 a plan, partly in horizontal section, some of the parts being removed.

page_text: Figure 4 is an end elevation of the instrument viewed from the left hand side of
Figure 1, some of the parts being removed, and the pivoted arm or plate hereinafter
described being shown in the vertical position.
Figure 5 is an end elevation of the instrument viewed from the right hand side of
Figure 1, some of the parts being removed, and the said pivoted arm being shown in
the vertical position.
Figure 6 is a section illustrating details of construction.
Figures 7, 8 and 9, are different views illustrating further details of
construction.
Figure 10 is a plan showing a modification of one part of my invention, and
Figures 11 and 12 are face and edge views of the diaphragm, illustrating another
modification of my said invention.
Like letters indicate corresponding parts throughout the drawing.
A is a frame or standard secured to the base B of the instrument, on which is also
mounted a separate post or standard A. C is the driving-shaft which is mounted
in the frame or standard A and is frictionally geared, by means of conical
pulleys, D, E, with a shaft F working between adjustable centres F¹ secured in the
frame or standard A, the pulley D being adjustable relatively to the pulley E to
compensate for wear by moving the said along the shaft C, the said pulley being
provided with a collar or hub D¹, and being secured on the shaft C by means of a
set-screw D. On the shaft F is fixed the rotary feed roller or drum G to which a
strip, tape or band 6 of suitable material for receiving the sound record or inden-
tations, is conducted from a reel K, the said strip or band being passed under a
guide-roller L.
To ensure sufficient grip or adhesion between the strip or band b and the feed-
roller G, a small tension-roller H is provided, preferably on the side remote from
the reel K, the said tension-roller being mounted on a lever J pivoted at J¹ to the
frame or standard A, and being held in position, either against the feed-roller with
the desired pressure or away from the said roller, at will, by means of a flat spring v
having a V-shaped lug v' at its free end which bears upon a suitable V-shaped tail-
piece J' on the lever J.
The feed-roller G is formed with a guide-channel to receive the strip or band b
as it passes from under the guide-roller L, the said channel being either formed with
a central groove at its bottom or being covered with a yielding substance to permit
of the recording or reproducing point or style S acting in an efficient manner upon
the strip or band b.
The detached post or standard A¹ supports a pivoted or swinging arm P formed
with a recess or seat P* in which the diaphragm R is held as hereinafter
described.
In the arrangement shown in Figures 1 to 6, the diaphragm R is held in its seat
and dampened by means of a tension-regulator comprising a non-metallic ring t
which bears upon the said diaphragm at or near its edge, and is elastically held
against the same by adjustable spring fingers or arms c, secured to the plate P and
bearing against the ring t, the pressure exerted by the said spring fingers or arms
being varied as required by means of the adjusting-screw d whereby the tension of
the diaphragm can be regulated.
The pivoted arm or plate P is fixed on a short shaft P' suitably mounted between
the adjustable centres A', and is provided with an adjusting screw P' which bears
upon a stud A' fixed in the frame or standard, A, for the purpose of regulating the
position of the said arm or plate relatively to the feed-roller G and the strip or
band b, the said arm or plate P being held in position by an automatically-acting
spring u which is V-shaped at its free end, and engages with a pin or projection u¹
on the arm or plate P.
To the arm or plate P is attached the style-carrying arm T which is provided
with a spring T and with a projection or stud which is held in contact with the
diaphragm. In the arrangement shown, the style S extends through a piece T' on
the upper side of the said arm T, and serves as the projection or stud to bear

page_text: against the diaphragm, so that the diaphragm acts directly upon the style. A
separate projection or stud may, however, be attached to the arm T for the purpose
above specified. Moreover the arm T may, if desired, be pivoted at one end to the
arm P and a spring be arranged to bear against its free end. An adjusting-screw T
is provided. by means of which' the arm is brought into the required position to
ensure the proper contact of the butt end of the point or style S with the diaphragm,
and since the arms P and T move together about.the pivots A³, the contact between
the point or style and the strip or band 6 may be varied by means of the adjusting-
screw P
The arm P is provided with an opening to receive the tube V for connection
with the mouth-piece or concentrator, which tube preferably has a diameter nearly
equal to that of the diaphragm.
The post or standard A has attached to it the reel-holder, which consists of a
flanged hub or bush K³ loosely mounted upon-a-pin or stud K¹, and provided with
a V-shaped projection or rib w¹ on which fits a corresponding groove w in the
reel, K, in such a manner as to ensure the rotation of the flanged hub with the
said reel. The reel is preferably made of paper, celluloid or other suitable light.
material, and the said flanged hub forms an efficient support or holder therefor.
If desired, suitable means may be provided for automatically rewinding the
metallic strip or band b as it is unwound from the reel and fed over the roller G.
And, if desired, instead of a strip wound on a reel, a continuous band of the record-
receiving material, may be used.
In Figure 10, I have shown a modification of my tension-regulator in which I
dispense with the ring t and arrange the spring arms or fingers c to bear directly
upon the diaphragm R.
Figures 11 and 12 illustrate another method of providing for dampening the
diaphragm, namely, by securing at its centre, with glue or other adhesive material,
a small circular piece R' of vulcanite, celluloid or other suitable non-metallic
material, of a diameter equal to one-third, more or less, of the diameter of the
diaphragm.
The material which I have found to be the most advantageous for the manufacture
of the recording band or strip, consists of a foil made from an alloy of lead and a
suitable percentage of one or more harder metals, such as tin, or tin and aluminium,
or bismuth and aluminium. In making a recording strip or band, therefore, I form
the same of a metal foil composed of from twenty to thirty parts by weight of
lead mixed with from seventy to eighty parts by weight of tin, or tin and
aluminium, or bismuth and aluminium, or other suitable harder metal or metals. I
am thus enabled to more easily make long lengths or strips of the foil of the
required thickness, and to obtain better results in respect of the recording and
reproduction of the sounds, than when a metal foil made from one metal alone is
employed. By using such alloys, moreover, I am enabled to make a foil which is
cheaper than ordinary tin-foil.
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 :-
First. The employment, in an instrument for recording or reproducing speech or
other sounds, of an adjustable tension-regulator exerting a variable pressure upon
the diaphragm between the centre and the circumference thereof, substantially as
hereinbefore described and for the purpose specified.
Second. The combination, with the diaphragm, of spring fingers or arms exerting
pressure thereon either directly or through the medium of a ring or annular piece,
and an adjusting device for varying the pressure exerted by the said spring fingers
or arms, substantially as, and for the purposes, set forth.
Third. The combination, with the pivoted or swinging arm in which the
diaphragm is held, of a spring arm attached thereto and carrying one or more
points or styles and having a projection or stud in contact with the diaphragm, and

page_text: an adjusting device for regulating the normal pressure of the said projection or
stud against the diaphragm, substantially as, and for the purposes, set forth.
Fourth. The improved apparatus constructed substantially as described with
reference to Figures 1 to 6 of the accompanying drawing and operating as, and for
the purposes, above specified.
Fifth. The combination, with the diaphragm, of a non-metallic stiffening piece or
dampener secured thereto by means of adhesive material, substantially as, and for
the purpose, specified.
Sixth. A recording or reproducing strip or band formed of metal foil composed
of lead and one or more harder metals mixed in or about in the proportions stated,
as, and for the purposes, above specified.
Dated the 7th day of November 1893
D. YOUNG & Co.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.