US1426970A - Sound box - Google Patents

Description

H. J. DURBOROW.

SOUND BOX.

APPLICATION FILED DEC.16. 1920.

1,4269% Patented Aug. 22, 1922.

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Qpeciflcation of Letters Patent. P@ fij@mtd1 A 22 11% Application filed December 18,1920. serial Itc. 481,088.

To all whom it may concern:

Be it known that l, HARRY J. Dunsonow, a citizen of the United States, resldlng at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Sound Boxes, of which the following'ls a specification.

One object of my invention 1s to prov1de an improved sound box for talking machines, which will be instrumental 1n more accurately reproducing sound than devices previously used for this purpose Another object of my present inventlon 1s to distribute and equalize the impulse caused by the connection of the stylus bar to the diaphragm prior to the passage of the sound waves through the tone conducting portion of the machine.

A. further object is to make the devlce of my invention of a simple and durable construction which can be readily manufactured.

These objects, and other advantageous ends which will be described hereinafter, I attain in the following manner, reference being had to the accompanying drawings in which Figure 1 is an enlarged fragmentary sec tion taken centrally through a sound box made in accordance with my invention; the stylus bar being shown in outside view;

Figure 2 is a section taken on the hue 22 of Figure 1, v

Figure 3 is a front face view of a member whichforms a part of my invention in the construction illustrated,

Figure 4 is an edge view of said member, and

Figure 5 is a rear view of said member.

Referring to the drawings, 6 represents the frame of a sound box including a recess 7 in which is mounted a diaphragm 8;

said diaphragm being positioned between gaskets Q9 and 10; the gaskets being confined within the recess and between a ring 11 and a shoulder '12. A circular cavity 13 leads inwardly from theshoulder 12 and communicates with an axial passage 14 which forms a art of the sound conductis provided by a' nipple extension or sleeve 15 whereby the sound box can be attached to a tone arm or other sound conducting member as is common practice in the manufacture of talking machines. .llhe stylus bar 16 is centrally connected at 17 to the diaphragm 8.

A member 18, the detail construction of which is shown in Figures 3 to 5 inclusive, fits within the cavity 13 and is held between the inner surface or wall 19 of said cavity 13 and the gasket 10. This member 13 may be made of hard or tough springy wood and on its rear face has a number of radially extending grooves 21. These grooves communicate with each othen at the axis of the member 18 and lead outwardly to respective notches 22 which are cut into the. peripheral edge portion; said notches communicating with the space between the diaphragm 8 and the front face 23 of the member 18. The portions of the face 20 between the grooves 21 preferably engage the wall 19 and the gaskets 9 and 10 are preferably. made of rubber so as to resiliently hold the member 18} in place. Thus there is a solid portion of the member 18 interposed between the central connection of the stylus bar with the diaphra and the sound outlet 14; the diaphragm 8 also being spaced from-the face surface 23 of the member 18 to provide a chamber 24. The vibrations of the stylus bar 16 affect the diaphragm 8, the greatest impulse occurring adjacent the. axis or central portion of the diaphragm, and sound waves are set up in the chamber 24; the stronger waves occurring in the central portion of said space. Ordinarily these( stronger sound waves would precede other portions of the waves directly outward throughthe passage 14 if themember 18 were not present. With my improved structure, however, all of the sound waves are compelled to pass radially or to spread out from the axis of the chamber 2 1 and eventually pass through the notches- 22 and grooves 21 and finally pass through the passage.

' I have found in actual experience that a more clear and definite reproduction is produced by the construction above described and also that the member 18 serves as a resonator which greatly improves the quality of the sound.

The member 18 therefore forms a resonat= ing partition which also serves in the ca-' pacity as a distributor and equalizer for the sound waves set up by the vibration of the diaphragm.

- tion may be changed without departing from the spirit thereof, and hence ll do not limit myself to the preclse construction set forth, but consider that I am at liberty to .make such changes and alterations as fairly come within the scope of the appended claims.

ving thus described my invention, what I claim as new and desire to secure by Letters Patent is p 1. A resonating partition for use 1n a talking machinesound box case includmg a portion providing a sound outlet passage, said partition being located between the diaphragm and the sound outlet passage of one face and sound outlet openings communicating with said grooves, said grooves also being in communicatlon with said sound outlet passage of the case; substantially as described. 1

2. A resonating partition for use 1n a talking machine sound box case including 1 an inner wall having a sound outlet passage,

said partition being located between the rel-some die hragm and the'inner wall of the case, sai partition, having passages leading toward the axis thereof and being in com- -munication with the sound outlet paaage and with the; space between the partition and the diaphragm; substantially as described.

3. A resonating partition for use in a talking machine sound box case including an inner wall having a sound outlet passage, said partition being located between the diaphragm and the inner wall of the case, said partition having grooves in one face and notches communicating with said rooves, said partition being. adapted to e placed in said case with said face opposed to said wall of the case sothat said grooves provide passages communicating the case, said partition havlng grooves 1n with the outlet passage and with said notches; substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses. J

HARRY J. nnanonow.

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