US1489257A - Support for mounting phonograph motors and the like - Google Patents

Description

April 8 1924. 1,489,257

G. R. LEGGETT ET AL SUPPORT FOR MOUNTING PHONOGRAPH MOTORS AND THE LIKE Filed Oct. 18, 1920 H 4 F m I] ,m 1 F- A 8 III i pr. 8, i924.

irao srras PAE GEORGE E. LEGGIETT AND JAMES LEE, 0F WATEBBUBIY, CONNECTICUT, ASSIGNOBS T0 SQOVILL MANUFACTURING COMP, A. CORPORATION 0F CONNECTICUT.

SUPPORT FOR MOUNTING PHONOG t MOTORS AND THE Application filed October 18, 1920. Serial Ho. 417,835.

To all whom it may concern:

Be it known that we, Gnonen R. Lneern'r and James LEE, citizens of the United States, residing at Waterbury, county of New Haven, and State of Connecticut, have invented certain new and useful Improvements in Supports for Mounting Phonograph Motors and the like, fully described and represented in the following specification and the accompanying drawings, forming a part of the same.

This invention relates to certain improvements in supporting devices for the motors of phonographs and similar motor driven instruments.

It is the especial object of the invention to produce a motor suspension by the employment of which the noise caused by the .vibration of the motor is counteracted or .deadened so that this noise is not transmitted to the instrument frame and is rendered practically unaudible, this suspension being of such character and material as to provide a substantially rigid support for the motor to permit of the winding up of. the motor.

It has been found in practice that this result may be obtained by providing a motor support of a resonant material in which vibrations may be set up, this support having a period of vibrations different than that set up by the motor and secured to the frame or casing forming a part of thecabinet of the phonograph or like instrument, this sup port being secured to the frame so as to leave a portion free to vibrate, as between the points of attachment, and by securing or attaching the motor to this support at the free portion. To effect the best results the support should be of a material and dimensions having a vibratory period slower than the vibration period of the motor, and the support should be of suificient length between the points where the motor is attached to it and the points where it is attached to the frame to permit the sound waves set u therein by the motor vibration to trave over a distance greater than one of the slowest wave lengths, so that the sound waves set up in the support will meet and counteract and deaden the higher wave lengths set up by the motor, and preferably to effect the greatest sound deadening results, the distance the support extends beyond the points of attachment of the motor should the frame to which thesupport is attached and at the same time to permit of the required rigidity for permitting the winding of the motor.

One such construction for effecting the results aimed at is shown in the aocompany ing drawing, in which- Figure l is a. side view partially in section showing parts of a phonograph cabinet frame with the motor supported in accordance with the invention.

Figure 2 is a side view of the construction shown in Fig. l. 1

Referring now to these drawings, the invention has been illustrated as embodied in a phonograph of the rotary flat disc type, but it will be understood that it is intended to and may be used in supporting the motor driving mechanism of other types of phonographs or other types of motor driven musical instruments. As shown'the motor mechanism is secured to a frame 1, which may be the top or table of a phonograph cabinet. The motor mechanism for operating the phonograph comprises a motor frame 2 and a spring motor 3 of the usual type, shown in Fig. 1. 1

Attached to the lower side of the frame or base 1 is a support of resonant material having a period of vibration slower than that of the motor whi h is supported by it. While the dimensions of this support and the material of which it is made, may

be widely varied, the support will be of a sufliciently rigid material to support the motor so that it may be properly wound and will be dimensioned so that itwill extend beyondthe points at which the motor is attached to it a sufiicient distance so that the wave lengths set up therein may travel a suflicient distance to counteract the higher period wave lengths transmitted to it by the motor.'

In practice it has been found that a support in the form of a pair of strips 4, 5 of leaded brass will provide a material of sufliciently slow vibration period and rigidity to effect the purposes desired and in the best constructions the support will be in the form of these strips. These strips 4, 5 are secured to the support in any suitable manner, as for instance, by screws 6 and nuts 7, and referably insulating discs or washera 8 0 rubber or other suitable sound insulating material are provided between the 110 the strips.

strips and the base, these insulating discs 'also acting to raise the strips away from the discs so as to allow a. free portion between the supporting screws, so that vibrations of the desired character may be set up in The motor frame 2 is attached to these supporting strips 4, 5, being in the (particular .construction illustrated, suspen ed from the strips so as to be out of the way when the base or table 1 is mounted in the phonograph cabinet, and the motor frame 18 secured to these strips at the free portion, that is, the portion between the points of attachment of the strips to the base or table' 1. Preferably insulating washers or discs 10 of rubber or other suitable sound insulating material are lo-* cated between the motor frame and the strips, and these discs 10 with the disc 8 aid in deadening the sound.

The strips 4, 5 as shown, extend beyond the points of attachment of the motor a sufficient distance so that the vibrations set up in the strips may cross and counteract the higher wave lengths transmitted to the strips from the motor. The distance that the strips extend beyond the motor may, of course, be widely varied depending on the dimensions of the strips and the space which is permitted by the dimensions of the base or table 1.

The motor mechanism drives a shaft 11 through gear connections, not necessary to describe, which operates the turn table 12 which sup rts the record disc.

With this construction the. vibratory hum of the motor is practicall eliminated and a support provided'of su cient rigidity to properly support the motor mechanism and permit of its being wound, any wobbling of the motor being eliminated which would interfere with the winding operation.

'While one construction, which has been found in practice to effect the object and results of the invention has been shown and described, it will be understood that various changes may be made in the form of the supports and the material of which the su ports are made without departing from til invention.

What we claim is: Y

1. In a motor support for phonographs I and similar motor driven instruments, the

combination of a base, a rigid su port of resonant material attached to the base and having a portion free therefrom between the oints of support in which vibrations may e set up, a motor mechanism secured to the and similar motor driven instruments, the

combination of a base, a rigid support of resonant material attached to the base and having a portion free therefrom in which vibrations may be set up, and a motor mechanism secured to the support at its free portion said support having a fundamental vibration period sufliciently slower than the vibration period of the motor mechanism which is transmitted to the support at normal running speed, said support extending beyond the points of attachment of the motor at each side a distancesuflficient to permit the slower vibrations of the support to counteract the higher vibrations produced by the motor and cause the resultant Vibrations to be substantially inaudible.

3. In a motor support for phonographs and similar motor driven instruments, the combination of a base, a pairof rigid strips of leaded brass secured to the base at each and similar motor driven instruments, the

combination of a base, a pair or rigid strips of leaded brass secured, to the base at eachof their ends and free therefrom between the points of attachment, anda motor frame secured to the free portion ofthe stri the free portions of the stri s extending yond the motor frame at eac side.

5. In a motor support for phonographs too and similar motor driven instruments, the

combination of a base, a pair of rigid resonant metal strips secured to the base at each of their ends and free therefrom between the points of attachment, and a motor mechanism secured to the strips between their points of attachment to the base. 1

In testimony whereof we have hereunto set our hands. Y

- GEO. R. JAMES LEE.

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