US1513187A - Sound reproducer for talking machines - Google Patents

Description

c. SCRABIC SOUND REPRODUCER FOR TALKING MACHINES Filed April 5, 1922 2 Sheets-Sheet 1 i I I awue/ wtoz a1! flaraiik I c. SCRABIC SOUND REPRODUCER FOR TALKING MACHINES z'sheezs-snee'. 2

: Filed April 5, 1922 box.

Patented Get. 28, 1924.

ED SITES CARL SGRABIG, or UQRBANA, OHIO.

SOUND nnrnonuonn roe TALKI G ACHINESJ Application fiiled' April 3,

To all whom it may concern:

Be it known that CARL ScRA ro, a citizen of the United States, residing at Urbana, in the county of Champaign and State of Ohio, has invented certain new and useful Improvements in Sound Reproducers for Talking Machines, of which the following is a specification. Y i

This invention relates to an improved sound reproducer or sound box for talking machines, and has for an object theprovision of a sound box wherein the diaphragm will be mounted to vibrate within a closed chamber for the purpose of confining within the sound box the sound disturbances created by the vibration of.thecdia-. phragm and preventing such disturbances from unduly escaping or becominguselessly dissipated into the atmosphere without being amplified, and to providec a common source of sound amplitude. v An object of the invention resides in mounting the diaphragm so that similarior' exact conditions will prevail on both sides thereof for the purpose of securing uniformity in the amplitude or pitohof the erence denote like and corresponding-parts throughout the several views thereof;

In said drawing: 5 i

Figure -1 is a vertical longitudinal sectional viewtaken through the sound box constructed in accordance with the present invention, I

- Figure 2 is a sectional view taken on the plane indicated by the line 22of Figure 1, 4 i

Figure 3 is a sectional view on the line 3-3 of Figure-J1, and x V Figure 4 is a side elevation of the sound.

Referring more particularly to the -details of the invention the numeral 1 designates the improved sound box comprising 1922. Serial No. 548,982.

upon the outer edge of which is placed and. secured a cover plate 5, the latter being. se-- curedas at 6. to the flange 4, and when connected as shown this .casing will producean enclosed air tight chamber 7 inwhicha diaphragm 8 will be supported for vibration.

the present invention in its entirety; In the i The sound box is adapted to be connected with the outer; end of a tone iarm 9"and my preferred structure for effecting this connection: consists in providing-the outer The said collar is provided-with radially extending knife edge studs or trunnionsi 1 1, which are adapted to be received within. bayonetslots*12,1 provided ,in an exterior sleeve-'13, which is rigidly carried by the casing. 2'. The sleeve 13' terminates forwardly in an annular vertical flange 15, and

an annular gasketlo is arrangedto be situated between the flange 15 and the wall3. of the'casing to prevent direct contact of adjoining metallic parts. Screws 17 are employed to directlfybonnect the flange 15 with :the wall 3; The forward ends of the collar lOand sleeve 13 are provided with registering-annular grooves, in which is seateda ring 18 of rubber or-other resilientmaterial,

which is confined between the wall 3 and the fiber Washer. .119 also fseated within the grooves contained in the, ring 18. By this construction it will be seen that-thefSound box may be detachably andffiexibly connected-with the outer end of the tone arm by first inserting the sleeve 13 over the collar 10 sothat the studs'll will bereceived 3 within the longitudinally"extending portions of the bayonetslots 12. Then, by'ro-- tating the sound box bodily aboutthe tone 1 within the circularly disposed portions of.

arm -9, thesaid studs 11 will be positioned the slots 12, ,thus securely locking the re- 7 producer in an operative position upon the tone arm; When the studs 11 are in'the circular portions of the slots 12thering' 18 will becom'nressed, causing the same toexercise. a sufficient degree of pressure toretain the studs in the'slightly enlarged. ends of the slots 12; and thereby preventing loss of adjustmenton the' part of the sound box.

Byformingthestuds 113111 triangular or knife'shaped form the samewill act as trunnions, permitting of limited oscillation on the part of the casing 2 relative to the outer end of the tone arm. It will be observed that the sleeve 13 is formed in two parts, the outer part servingto conceal the studs 11 and the slots 12 so as 'topresent a neat and finished appearance to the sound box when the latter is in use. This construction is fully set forth in my co-pending applica tion Serial Number 4565M?) filed Mar. 28,

I The gist of the present invention resides inmounting the diaphragm 8 within the casing 2 so that'the diaphragm will be completely encased by the sound box and re 'moved from disturbing extraneous conditions, means being provided for directing sound disturbances created on both sides of theenclosed diaphragm to a common outlet, to insure unlformity 1n the amplitude of the sound disturbances set up on both sides of concentrically dispose-d within the enlarged bell shaped mouth 25 of the collar 10, however, itwill be observed that the adjoining walls of the-mouth 25rand the conduits 23 v and 24; are relatively spaced. To support the plate 20 within the casing, the wall 3 is provided with a plurality :of inwardly extend-ingscrews 2,6, which pass through open- -in'gs provided peripherally in the circumferential portion 22! of the'plat e 20, and fiberor other similar washers 27 surround the screws 26 and'are interposedbetween the wall 3 and the plate 20, so as to space the latter from the wall 3 to provide a space B whichcommunicate's with the space B existingbe tween the conduits 23 and, 24, which'space' B is in direct communication with the end of the tone arm 9. Coopera "tive with the plate 20 is a complimental plate 28, which is provided with an enlarged body portion 29 having an axial opening or conduit 30 formed therein which is of the same size as the conduit 23 and issituated in registration therewith. The. body portion 29 terminates near its periphery in a reduced wall 31 and is provided with acircumferential flange 32, arranged to receive the circumferential portion 22 of; the plate 20,-the said flange 32 being provided with threaded openings 33'17 1 h ,ree'ept onof the ends of the screws 26, whereby when the latter are tightened into place the'same will serve to securely retain the diaphragm plates 20 and 28 in assembled relationship. By effecting relative: approach between the plates 20 and 28 diaphragm gaskets 34 are compressed and retained with the circumferentially reduced portions 22- and 31 of said diaphragm plates, for the purpose of engaging with the perimeter of the diaphragm 8,'freely supporting the latter for vibration between said plates in a manner common to diaphragms of this character generally.

The outer plate 28 is spaced from the cover or diaphragmclosure 5, and similarly the flange 32 is spaced from the casing flange 4 for the purpose of producing spaces in engagement C and C" which communicate directly and freely with the spaces B and B. The closure 5 is formed witha vertical de ression 35 providing. a groove 36, in whic is-po sitioned for movement the upper end of a stylus 37 having direct connection with the diaphragm 8. 'The lower endof the groove 36 is provided with a compressible ring 38,

:which surrounds the stylus 37 with a suffidistantly from the diaphragm plates 20 and 28 so asto be capable of vibrating there'- b'etween" in conformity with the vibratory movement of the stylus. By forming the conduit 23 and the opening 30 of'the same diameter and in equally'spacing the diaphragm from the plates 20 and 28 sound disturbances created by the vibratory movement of the diaphragm will be of equal pitch or amplitude onboth sides thereof for the purpose of enabling thefsound disturbanc'es. to be properly equalized and to pass v in unison through the common outlet pro vided by the tone arm. I am aware'that structures have been heretofore proposed wherein a diaphragm is positioned for vibration within a closed chamber, and I therefore do not claim such a construction broadly, the present invention, however,

not only encases a diaphragm but produces a structure wherein the sources of amplitude on both sides of the diaphragm" are of substantially the same proportions and wherein the sound waves are discharged through a common outlet, namely, the tone arm, ofan associated amplifier;

What is claimed is: r In a sound reproducer for talking ma.-

chines, an enclosed casing, a diaphragm sup portlng structure mounted Within and spaced from the Walls of said casing, said structure including a compartment, a dia phragm mounted Within said compartment and spaced equidistantly from the Walls thereof, an oscillating stylus extending into said casing for cooperation With said diaphragm, and conduits of equal diameter sides of said diaphragm, a third conduit carried by the supporting structure and disposed in concentric spaced relation With an adjacent conduit, all of saidconduits being in communication With a commonsound 15 outlet.

In testimony whereof I aflix my signature.

CARL SGRABIC.

Images