US1708320A - Sound-box mounting - Google Patents

Description

April 9, 1929. M NYSTROM 1,708,320.,

S OUND BOX MOUNTING Filed May 25, 1927 .5 0 j [if Fig-5 I :I l rvij ,*-r*:

Inventor: F295 Hutin N strom.

Patented A 9 19 UNITED STATES 1.7%,326 PATENT OFFICE.

MARTIN NYSTR-OM, OF CHICAGO, ILLINOIS, ASSIGNOR TO BRUNSWICK-BALKE- COLLENDER COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE,

' SOUND-BOX Application filed May 25 7 This invention relates to sound boxesfor talking machines and has a special relation to mountings by which the sound boxes are secured to tone arms.

An object of the invention is to provide an especially durable and simple vibration insulating mounting for sound boxes.

Other objects and advantages will appear as the description proceeds.

Fig. 1 is a side elevational view, partly in section, of a sound box and tone arm connection embodying the invention;

Fig. 2 is a rear elevational view of the sound box;

Fig. 8 is a side elevational view of one end of the tone arm;

Fig. 4 is a front elevational view of the same; and

Fig. 5 is a sectional view taken on the line 5-5 of Fig. 4.

Referring to the drawings 1 indicates a sound box casing having a diaphragm 2. The back plate 4.- of the sound box casing is provided with a sleeve 7 formed integral therewith or otherwise attached thereto, which is spaced outwardly of an opening 8 in the back plate.

A tone arm 10 has secured thereon by means of pins or rivets 11. or in any other suitable manner, a collar 12 made of metallic material such as aluminum for example. While aluminum is preferable, it will be understood that other metals may be used. Lead, for example, has been employed, but due to its weight would not be so desirable as aluminum. The collar 12 constitutes substantially an enlargement of the end of the tone arm and is of such a size and thickness that it will fit snugly in the sleeve 7 on the sound box. Two of the pins or rivets 11 may extend beyond the outer face of the collar and are adapted to engage in bayonet slots 13 provided in the sleeve 7 for detachably securing the tone arm to the sound box.

. In order to obtain a tight and snug connection between the tone arm or sound conveying tube 10 and the sound box casing, the collar 12 may be provided with plurality of cushions 14 preferably of soft rubber. although cork or other resilient material may be used, adapted to bear against the back plate 4 when the parts are assembled. In the construction illustrated three such cushions spaced an equal distance from each other are provided, although a smaller or larg- MOUNTING.

1927. Serial No. 193,994.

or number may be used. The cushions 14 are disposed in openings 15 provided in the collar and are held in place by friction or an adhesive substance such'as glue. The rear of the openings 15 communicate with the atmosphere by means of small ducts 16 which permit the escape of air when the cushions are forced into the openings and thus facilitate the assembly of the cushions. As the cushions bear against the back plate, they maintain the sleeve in engagement with the pins 11 and prevent vibrations set up in the sound box from causing the sleeve to rattle against the pins.

The novel mounting prevents relative movement between the sound box and the tone arm and also prevents vibrations in the sound box from being transmitted to the tone arm and in fact, acoustically insulates the sound box. Thus vibration of the tone arm is prevented and the quality of reproduction of the talking machine is enhanced.

The aluminum collar 12 will remain in operative condition indefinitely as it will not corrode nor will it be torn away or otherwise damaged when the operator removes or replaces the sound box.

While the collar is shown secured to the tone arm, it will be understood that it may be connected to the sleeve or, if preferred, it may be placed on the inside of the tone arm, in which case the sleeve would also be connected on the inside; the main object being to effectively sound insulate the two members from each other.

While I have described a preferred form of my invention in detail, I do not wish to be limited to the exact form shown for many changes may be made within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim as new and desire to secureby Letters Patent of the Jnited States is 1. The combination of a sound box, a sleeve, a tone arm having a tubular end, arranged coaxially within said sleeve a metallic collar interposed between the sleeve and the tubular end and resilient cushioning members seated in said collar and extending therefrom, said metallic member serving as a rigid support for said resilient projections.

2. The combination of a sound box cas ing having a back plate with an opening therein, a sleeve formed integral with said back plate and spaced outwardly from the opening, tone arm having a collar secured thereto means for mounting said collar-on" saidsleeve and resilient'means carried by said collar and compressed between said collar and said back plate when'the parts are assembled. 5

3. The combination of a sound box casing provided with a back plate having an opening and a sleeve on said back plate, a

tone arm having" a. collar secured thereto pressed between said collar and said back plate adjacent said opening; therein when the parts are assembled, and means for detachably securing said collar tosaid sleeve.

The combination. of a sound boxhaving anopening a tone arm having an enlarged end which is provided with a pluralityof openings,a plurality of cushions fitting in said openings respectively, and projecting therefrom and engaging said sound box adjacent said opening and means to detachably secure-said tone. arm 'tosaid T NYSTROM;

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