US2342457A - Tone arm - Google Patents

Description

Feb. 22,4 1944. R DALLY I l Y 2,342,457

TONE ARM Fild. 0G11. 16, 1942 Pemba ret. ze, 1944.

UNITED STATES PATENT oFElcE e t Y 2,342,457

TONE ABM Boy Daily, Racine, Wis., slsilnor to Webster Electric Company, Racine. Wis.. a corporation o! Delaware lclaim.

'I'he present invention relates to tone arms and is particularly concerned with the provision of an improved device for holding the tone arm in fixed position adjacent the turntable when it is not being used. l

One of the objects of the invention is the provision of an improved tone arm support construction by means of which the tone arm may be most conveniently mounted in a fixed relation to its support adjacent the turntable whenever it is not being used. A

Another object of the invention is the provision of an' improved tone arm support of the class described which is sturdy, capable of being manufactured at a low cost and adapted to hold the tone arm securely and to release it when desired.

Another object of the invention is the provision of an improved tone arm and tone arm support construction in which the channel construction oi' the tone arm is used for engaging a compressible support by means of friction in such manner that it may be forced on the support and forcibly removed Without necessity for providing any latches.

Other objects and advantages of the invention will be apparent from the following description and the accompanying drawing in which similar characters of reference indicate the same parts throughout the several views.

Referring tothe single sheet of drawings,

Fig. l is a fragmentary plan view of a tone arm carried by a support and provided with a turntable and an auxiliary supporting member constructed according to the invention;

Fig. 2 is a bottom plan view of the tone arm; and

Fig. 3 is a fragmentary sectional view taken on the plane corresponding to the line 3 3 of Fig. 1 and looking' in the direction of the arrows showing the details of the construction of the auxiliary support whenthe tone arm is supported on it.

Referring to the drawing. ill indicates the support for the turntable and tone arm which may consist of the top panel of a phonograph housing. The top panel III is provided with a suitable column II adapted to support the tone arm l2 at the left end of Fig. l for a limited universal movement. The tone arm I2 is adapted to pivot laterally on the column II to follow the groove in the record, and it is also adapted to pivot upward on a horizontal axis so that the tone arm may be lifted from the record or placed upon it.

The tone arm I2, which is shown in bottom plan in Fig. 2, is preferably of a channelled construcf crystal pickup I5 is merely exemplary of one type 'tion 33 is enlarged to provide of reproducing mechanism carried by the tone arm. 'The crystal pickup I5 is provided with a checkl I6 carrying a stylus I'l. 'I'he conductors I8. and I9 from the crystal pickup I5 extend longitudinally of the interior of the channelled tone arm I2 to the fixed connectors 20, 2|. The side.

flanges I4 and I5 preferably extend around the full outer Wall. oi the tone arm, but the bottom of the tone arm is preferably open and the anges I 4 and I5 are` preferably relatively thick at the intermediate part of the arm where they are adapted to engage the auxiliary support 22. The auxiliary support 22 is shown in detail in Fig. 3, and it comprises a column carried by the panel I0 and adapted to support the tone arm in its fixed position. This column may consist of a screw bolt 23, the head 24 of which is preferably of the countersunk type provided with a slot 25 for a screwdriver, and the lower threaded end 26 of also passes through a tubular member 30, which may be made of metal or suitable insulating material such as a phenolic condensation compound. i Y

The tubular member 3Il has a through bore 3i for passing the screw bolt 23. Its lower endl 32 is preferably plane so as to engage the panel I0 and to provide a suitable base. The lower end pora larger area for the end or base surface 32.

At its upper end the tubular member 30 may also have a plane surface 34 for engaging the resilient compressible head 35. The resilient compressible head 35 comprises a substantially cylindrical member of resilient rubber or other suitable resilient material such as a printers roll composition. n It has an axial throughbore 36 for passing the screwl bolt 23, and has a countersunk depression 31 for receiving the head 24 of the screw bolt. Its upper corners 38 are preferably rounded to provide atapered surface adapted to enter between the anges I4 and I5 of the tone arm more readily.

The resilient head 35 is fixedly supported on the column 22 by means of the bolt 23 and tubular member 30. It is preferably located on the panel I0 opposite the turntable 39 and slightly spaced from the turntable in such a position that the tone arm may be lifted from the record and it may have its channel brought into registry with the top of the head 35 and then the tone arm may be forced down upon the head 35. The flanges I4 and I5 then compress the head 35 as the head 35 passes between the flanges, and the tone arm is frictionally engaged on the head. It may be removed from the auxiliary support 22 by merely lifting it and overcoming the friction which holds it on the head, but the friction is-suflicient to support the weight of the tone arm when the phonograph is inverted. Furthermore, the height of the column 22 may be made such that when the vtone arm is carried by the auxiliary support 22,

its upper flange I3 is just -below the cover of the phonograph which is secured by a suitable lock so that the tone arm cannot come off the` auxiliary support 22.

It will thus be observed that I have invented an auxiliary support for tone arms which is adapted to receive the tone arm and hold it when the tone arm is merely pressed upon it. The height of the column is such. that the needle is always held out of contact with the panel or turntable or record, and the column may also be made of such height that the tone.

arm is carried immediately below the cover of the phonograph so that it cannot be accidentally dislodged from its auxiliary support. This auxiliary support may be constructed at a low cost; it is sturdy and capable of being used for a long period of time without repair. It is convenient because it is only necessary to push the tone arm down upon it when it is to be secured on the support, and it is only necessary to pull the tone arm off when it is to be used.

The head 35, being of cylindrical shape, does not affect its operation if it should rotate slightly upon the supporting bolt 23, as it is always in proper position -to be engaged by the tone arm. The rotation of the head permits new surfaces to be brought into engagement with the tone arm and enables the user to compensate for any wear that takes place.

Since the head 35 is of compressible material, it may be expanded laterally by -means of the threaded member 23 and tubular member 30 which are adapted to place a compression on the end surfaces of the cylindrical member 35 to expand it into a larger diameter and into better frictional engagementv with the tone arm whenever necessary.

While I have illustrated a preferred embodi- V ment of my invention, manymodifications may be madewithout departing from the spirit of the invention, and I do not wish to be limited to the precise details of construction set forth, but desire to avail myself of all changes within the scope of the appended claim.

Having thus described my invention, what I claim as new and. desire to secure by Letters Patent of the United States, is:

In a phonograph, the combination of a supi porting panel with a column for supporting a tone arm, an auxiliary support for the free end of said tone arm, comprising a tubular sup,-

porting member having an enlarged bas'e for

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