Improvements in Sound Recording and Reproducing Machines.
Year: 1898

page_text: Date of Application, 12th July, 1898-Accepted, 26th Nov., 1898
COMPLETE SPECIFICATION.
Improvements in Sound Recording and Reproducing Machines.
I, ELDRIDGE REEVES JOHNSON, of No. 108, North Front Street, City of. Cam-
den, State of New Jersey, United States of America, Machinist, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed to be particularly described and ascertained in and by the following
statement:
-
My invention relates to certain improvements in sound recording and re-
producing machines and in mechanism for actuating the same and has for its
object to provide an improved form of machine which may be driven by a small
spring motor.
A further object of the invention is to provide an improved form of sound box
and stylus carrying board and to provide for the accurate and delicate adjust-
ment of the stylus bar with respect to the diaphragm. A further object of the
invention is to provide an improved form of support for the trumpet and to
simplify the construction of the same and the connection between the trumpet
and the sound box.
A further object of the invention is to simplify and improve the supporting
mechanism of the table or platform which carries the record disk.
A still further object of the invention is to provide an improved form of spring
motor for actuating the machine and to provide means for regulating the speed
of rotation of said motor, and a still further object is to provide for the regu-
lation of the speed of rotation of the record carrying platform independent of the
means of governing the speed of the motor.
Further objects of the invention are generally to simplify cheapen and im-
prove the appearance of the machine, as more fully set forth hereinafter.
In the accompanying drawings:-
Fig. 1 is a perspective view of a sound recording and reproducing machine
constructed in accordance with my invention.
Fig. 2 is a sectional plan view of the same on the line 2-2, Fig. 3.
Fig. 3 is a longitudinal sectional elevation of the same on the line 3—3,
Fig. 2.
Fig. 4 is a transverse sectional view of the same on the line 4-4, Fig. 2.
Fig. 5 is a diagram illustrating the action of the motor governing device.
Fig. 6 is a transverse sectional view on an enlarged scale, on the line 6-6,
Fig. 1.
Fig. 7 is a similar view illustrating a modification of the structure shown in
Fig. 6.
Fig. 8 is an elevation of the sound box.
Fig. 9 is a sectional plan view of the same on the line 9-9, Fig. 8.
Fig. 10 is a view illustrating a portion of the sound box, drawn to an exag-
gerated scale.
Fig. 11 is a detached perspective view of the rear face of the sound box, and
Fig. 12 is a detached perspective view of the stylus and its support.

page_text: Referring to the drawings, A represents a suitable platform or base to which
is secured a framework, B, comprising upper and lower plates b, provided with
suitable bearings for the reception and support of a number of vertically
arranged shafts, a, a, a, a³, the latter shaft serving as a support for the circular
platform, C, on which the record disk is carried. The shaft, a, is squared at its
upper end to form a winding post and is adapted to receive a suitably shaped
key. This shaft is secured to one end of a spiral spring, the opposite end of
which is secured to one of the posts of the frame and is provided with suitable
ratchet mechanism such as is ordinarily employed in clock work to prevent the
uncoiling of the spring immediately upon the removal of the winding key. The
shaft, a, is connected to the shaft, a³, by suitable train of gearing, c, which trans-
mits the rotations of the shaft, a, to said shaft, a³, and effects the rotation of the
platform, C.
On the shaft, a³, is secured a worm wheel, d, the teeth of which intermeshi
with a worm, d, on a transversely disposed shaft, d², supported at its opposite
ends in suitable bearings the arrangement being such that as the train of
gearing, c, rotates the worm wheel, d, will revolve the worm, d, and its shaft at
a comparatively high rate of speed. On the worm shaft is secured a fan, D,
which is rotated with the shaft and serves to govern and regulate the speed of
rotation of the clockwork gearing.
The fan, D, is formed preferably from a single sheet of stamped brass or other
suitable metal and comprises two blades, e, e, which are connected at their oppo-
site ends by angular strips, et, to the worm shaft, d. The metal of which the
fan and its supporting arms are formed is very light and resilient and the
arms, el, are each bent at about a right angle and at their outer ends are con-
nected to the blades in a central or nearly central position so that if there is any
tendency to increase the speed of rotation of the train of gearing the arm will
yield and the fan blades will move further and further from the centre of
rotation. The angle at which the blades are set is such that when rotating there
will be a constant tendency to spread and when this tendency is increased by the
action of centrifugal force due to a higher rate of speed than the normal the
distance between the blades will increase and the air will offer much greater
resistance to their travel thus increasing the load on the clockwork and reducing
its speed.
In Fig. 5 the full lines designate the normal position of fan blades when the
motor is travelling at the proper speed and the dotted lines represent one position
which such blades may assume when the speed is increased. The degree of
bending of the arms, e¹, will at all times be governed by the speed of rotation of
the motor and in this way it is possible to at all times preserve an even and
regular speed and thus insure the more perfect reproduction of the record.
The shaft, a³, is provided with a pin, f, on which the central hub, c, of the
platform C, rests, said hub being cut away or notched at ², for the reception of
the projecting end of said pin, the construction being both simple and economical
and at the same time affording a secure support for the table and enabling
the rotations of the shaft, a³, to be transmitted to said table.
In some cases it may be desirable to provide for a means of adjustment of the
speed of rotation of the table, independent of the fan governor I employ a friction
brake in the form of a small plate spring, g, secured at one end to one of the
plates, b, of the motor frame and near its opposite end being provided with a
shoe, g, of felt, rubber or some similar material which may be pressed into con-
tact with the periphery of the shaft, a³, by means of a screw, 93, formed at one
end of elongated rod, g³, which extends out through the casing of the machine.
The motor and its governing fan are enclosed by a small metallic casing, G.
suitably shaped to conform to the outlines of the motor and its governor and
secured to the platform, A.
To one side of the casing is secured a spring stop, H, the upper end of which
projects slightly above the table, C, and on the inner face of this spring is se-

page_text: cured a small lug, h, which may enter a recess, h¹, formed in the side of the
casing. When the spring is moved with its securing screw and pivot to such
position that the lug, h, enters the recess, h, the spring will come into contact
with the periphery of the table and prevent the rotation of the same thus acting
as a means of holding the table stationary during the winding of the spring or
whenever it becomes necessary to change the record disks. By pulling out-
wardly on the spring and then slightly moving it until the lug, h, is out of line
with the recess, h, the spring will be forced out of contact with the periphery
of the table and will not interfere with the rotations of the latter.
Referring now to Figs. 8 and 12 inclusive I represents the sound box formed
of a single piece of cast metal. The front face of the box is curved in form and
around its outer edge is formed a circular flange, i, and within the flange is a
seat, ¹, for the reception of the diaphragm. The rear portion of the box is en-
larged to form a channel, j, connecting with the central opening, j, at the front
face of the box, but at a right angle thereto so that the trumpet may be con-
veniently attached to the box without the expense of auxiliary elbows or joints
such as are ordinarily employed.
The diaphragm, k, is formed of a disk of thin sheet metal or other suitable
material and is confined in place by a wax or gum of slightly elastic nature
which will permit of the vibrations of the diaphragm in response to the undula-
tory movement of the stylus. In fastening the diaphragm in place the sound
box is heated and a quantity of wax is placed all round the seat, , the
diaphragm which is just a trifle less than the diameter of the recess which it is
to occupy is then carefully pressed down upon the wax causing some portion of
the wax to exude between the periphery of the diaphragm and the inner wall
of the flange i, as more clearly shown in the exaggerated view Fig. 10.
The stylus support is in the form of a thin sheet of resilient metal stamped
and bent to form a strip 1, having its two ends bent at right angles to the main
body of the strip. The end, 7', as shown more clearly in Fig. 12 is provided with
two outwardly extending nibs or feet, 12, which rest against the centre of the
diaphragm and serve to insure a close joint between the diaphragm and the end
of the strip, a wax of slightly elastic nature being employed to bind the two to-
gether and extending partly over these two nibs or feet, 12. The opposite end, 3,
of the supporting strip is adapted to a small recess formed in the periphery of
the sound box and is provided with an elongated slot, 1, through which passes
a securing screw, m, the slot permitting of the adjustment of the strip to any
desired position and insuring the proper contact between the end, 11, of the strip
and the diaphragm, k. On the strip, 7, is secured a boss, n, having a transversely
disposed opening for the reception of the stylus, m', of the usual character, the
stylus being held in proper position by a set screw, n³.
In the recording or reproducing of sound waves the stylus supporting strip, I,
is so adjusted that the end 7, of the strip will be in perfect contact with the
diaphragm and as the latter is moved under the impulse of sound waves or as
the stylus is moved in the reproduction of recorded sound waves the strip will
bend to and fro with the juncture of the portions, 1, 13, of the strip or at a point
between there and the edge of the flange, i.
The trumpet, R, provided at its smaller end with an annular ring, r, from
which projects a small circular flange, r¹, adapted to enter the opening, j, in
the sound box and thus serving as a means of firmly connecting the trumpet to
the sound box.
About midway between the ends of the trumpet the latter is provided with a
diametral tube, s, through which extends a rod, t, secured to or forming part
of a supporting bar, t, the lower end of which is adapted to fit into a recess or
orifice in a bracket, V, projecting from the base, A. The upper portion of the
bar, t¹, is curved to conform to the contour of the trumpet and at its juncture
with the rod, t, is provided with a shoulder, u, between which and the face of
the trumpet is placed a washer, u¹, of rubber or other yielding material. At the

page_text: opposite end of the rod, t¹, is a nut, v, and between this and the face of the, trum-
pet is a similar washer, v. By supporting the trumpet in this manner the usual
brackets are avoided and the appearance of the instrument materially improved.
In the modified structure shown in Fig. 7 the tube, s, is soldered or otherwise
secured to the bottom of the trumpet but otherwise the connection with the sup-
porting post, t, is the same as that described with reference to Fig. 6.
When the instrument is not in use or the record disks are being changed the
sound box and trumpet are turned with the supporting post, t, as a pivot until
they rest upon a support, y, formed of a strip of wire having its upper end bent
to conform to the contour of the sound box.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is:
1. A governing device for a spring motor for use in sound recording and re-
producing machines, comprising a revolvuble fan having its blades hung to or
formed integral with supporting arms formed of resilient material.
2. A governor for use in sound recording and reproducing machines com-
prising fan blades and angularly disposed supporting arms, said arms being
adjusted to alter the plane of rotation of the blades under the influence of air
pressure, substantially as specified.
3. A governor for use in sound recording and reproducing machines formed
of a single sheet of stamped metal and comprising fan blades and angular sup-
porting arms, said arms merging into blades at the centre of the opposite ends
of said blades and being bent at about a right angle at a point between the centre
of rotation and the juncture with the blades, substantially as specified.
4. A fan governor for use in sound recording and reproducing machines com-
prising a rotatable shaft, arms, e¹, projecting therefrom, said arms being bent
at a right angle and fan blades, e, secured to or formed integral with said arms,
substantially as specified.
5. In combination, a revolvuble shaft or spindle, a pin, f, extending there
through, a circular record carrying platform, C, a hub, c, on said platform
having notches or recesses for the reception of the projecting ends of said pin,
and means for rotating said shaft or spindle, substantially as specified.
6. In combination, a rotatable shaft or spindle, a record carrying platform
supported thereby, means for rotating said spindle a friction brake, g, adapted
to bear against the periphery of said shaft, and an adjusting screw hearing
against said brake and adapted to regulate the friction between the brake and
the shaft, substantially as specified.
7. The combination with the clockwork mechanism and governor of the
casing G, and platform, A, surrounding and embracing said clockwork me-
chanism and governor, a shaft or spindle, a³, a record carrying platform carried
thereby, and a friction brake adapted to bear against the periphery of said
shaft, 3, substantially as specified.
8. The combination of the circular record carrying table, means for revolving
the same, a stop mechanism adapted to bear against the periphery of said table,
said stop mechanism comprising a movable spring, a support therefor, a lug, h,
on said spring adapted to bear against a supportor to enter a recess therein,
substantially as specified.
9. The combination of the motor mechanism, a casing therefor having
recess, h¹, a circular record carrying platform adapted to be rotated by said
motor mechanism, a spring, H, pivoted to said casing and adapted to make con-
tact with the periphery of the table, and a lug, h, secured to said spring and
adapted to enter the recess, h¹, or to bear against the surface of the casing,
substantially as specified.
10. A sound box having in its front face a circular recess for the reception of
a diaphragm and having its rear face enlarged to form a passage on
a line

page_text: parallel with the front face of the diaphragm and communicating with a cen-
trally located opening or passage extending from the front face of said sound
box, substantially as specified.
11. The combination with a sound box having in its rear face a sound con-
ducting passage or opening extending parallel with the diaphragm and having
its walls formed integral with the sound box, of a trumpet, and an annular
flange on the end of said trumpet adapted to said passage or opening, substan-
tially as specified.
12. The combination of the sound box, I, having openings or passages, j, j', a
diaphragm in said sound box, a trumpet, a ring, r, provided at the smaller end
of said trumpet, and an annular flange, r, projecting from said ring and adapted
to the opening, j, substantially as specified.
13. The combination of the sound box, I, having a circular flange, &, and a
diaphragm seat, i, of the diaphragm, k, of a diameter less than the diameter of
the inner wall of the flange, i, and an elastic connection between the periphery
of the diaphragm and its seat, substantially as specified.
14. The combination of the sound box, a diaphragm secured thereto, a stylus,
and a stylus supporting strip, l, having one of its ends bent at a right angle to
the length of the strip and provided with projecting nibs or feet, 12, for contact
with the diaphragm, substantially as specified.
15. A stylus support comprising a strip of thin sheet metal having its opposite
ends bent at a right angle to the length of the strip, one of such ends being pro-
vided with an elongated slot for connection with a support and the opposite end
having projecting nibs or feet for contact with a diaphragm, substantially as
specified.
16. The combination with the sound box and diaphragm of the stylus
support, 7, having its opposite ends bent at right angles to the length of the
support and connected respectively to the diaphragm and to the sound box, a
boss, m, secured to the support and recessed for the reception of a stylus, and a
set screw, n, for holding the stylus in position, substantially as specified.
17. A trumpet for a sound recording or reproducing machine having a trans-
versely extending tube and a supporting bar or rod extending through said tube
and adapted to hold the trumpet in position.
18. In a sound recording and reproducing machine having a flat circularly
operated record disk a trumpet supported sound box provided rigidly upon the
small end of the trumpet, said trumpet being pivotally secured in position to
allow of the free movement of the stylus in recording or reproducing sound.
19. The combination of the trumpet, a transverse tube, s; secured to or formed
integral therewith, a supporting bar, t¹, having a rod, t, secured to or formed
integral therewith and extending through said tube, a nut, v, on the outer
threaded end of said rod and washers of yielding material arranged in
contact with the opposite sides of the trumpet, substantially as specified.
Dated this 12th day of July 1898
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.