US2083037A - Phonograph turntable drive - Google Patents

Description

June 8, 1937. w, SCHWTTGEN 2,083,037

PHONOGRAPH TURNTABLE DRIVE I Fi led Nov. 27, '1955 INVENTOR. 4 WILLIAM A. SCHMITTGEN ATTORNEY.

Patented June 8 1937 UNITED STATES PHONOGRAPH. TURNTABLE DRIVE William A. Schmittgen, Elyria, Ohio, assignor to The General Industries Company, Elyria, Ohio,

a corporation of Ohio Application November 27, 1935, Serial no. 51,878

4 Claims. (Cl. 27439) This invention relates to phonograph mecha-- nisms and particularly to means for supporting and driving the turntables thereof.

The turntables of phonographs and the like are commonly driven by an electric or other motor and the speed of the motor is stepped up or stepped down by a gear type transmission. The torque applied by the motor to the turntable therefore is undulating in character, the

torque while continuous having wave-like variations therein caused by the successively engaging and disengaging teeth of the gears in the transmission.

Furthermore, vibrations in the motor and transmission mechanism are transmitted through the shaft to the turntable supported on the shaft. Both ofthese types of vibrations, transmitted to the turntable, modify and distort to greater or lesser degree the sound record reproo duced from the record supported on the turn- 2 table.

It is therefore an object of this invention to v provide an improved means for supporting and turning the turntable of a phonograph or the like which will prevent transmission to theturntable of vibrations of the driving mechanism.

Another object is to provide, in connection with the turntableshaft of a phonograph or like mechanism, means for absorbing variations of 3o torque and longitudinal and lateral vibrations of the shaft.

Another object is to provide an improved phonograph or like turntable drive.

Another object is to provide an improved phonograph or like turntable support.

Other objects will be apparent to those skilled in the art to which my invention appertains.

My invention is fully disclosed in the following description taken in connection with the accompanying drawing, in which:

Fig. 1 is a side elevational view with parts broken away of. a turntable drive embodying my invention;

Fig. 2 is a sectional view taken approximately from the plane '2- -2 of Fig; l; I

Figs. 3, 4 and 5 are, respectively, plan, front elevational and side elevational views illustrating separately an element'shown in combination with other elements in Fig. 1;

, Figs. 6, 7 and 8 are, respectively, plan, front elevational and side elevational views of another I element separately shown. Referring to the drawing, I have indicated generally at I a. housing within which is con tained a driving motor and transmission gears preferably of the same diameter as the washer 4 invention when the motor in the for driving a vertical turntable shaft 2, illustrated as projecting upwardly out of the housing A pin 3 extends diametrically through the shaft above the housing I, preferably being 5 driven into a hole in the shaft.

A metal clutch washer 4, rests upon the pin 3, the washer having a central perforation 5 upwardly through which the shaft 2 is telescoped. The washer 4 has, at diametrically opposite portions thereof where it rests upon the pin 3, pairs of downwardly projecting lugs 6-6 engageable with opposite sides of the opposite end'portions of the pin 3. Thus the lugs 66 provide, in effect, notches the sides of which embrace opposite end portions of the pin whereby rotation of the shaft 2 will positively be transmitted to the washer 4. The lugs 6-5 may suitably be pressed out of the metal of the washer 4 as plainly illustrated in the drawing. 20

Resting upon the upper side .of the washer 4 as viewed in Figs. 1 and 2, is a cushioning washer I of suitable cushioning or vibration-absorbing material such as rubber. The washer I is and has a central perforation 8 therethrough substantially fitting .the shaft 2 telescoped through the perforation. The cushioning washer 1 is provided with a pair of diametrically oppo site perforations 99 into which project teeth Ill-ill extending upwardly from the-washer 4. The teeth Ill-lll'are preferably formed by pressing them out of thematerial of the washer 4.

Upon the upper side of the cushioning washer I is a pair of clutch teeth ll-ll extending inalignment diametrically across the cushioning washer and preferably formed integrally there-. with. The clutch teeth l'l are wedge-shape in cross-section as plainly shown in Fig. 1 having inclined sides Iii-l2. 49

The turntable I3 is provided with a hub 14 on the underside thereof and secured thereto in any suitable manner, for example by being riveted thereto by means ofa flange IS. The hub 14 is preferably of substantially the same 45 diameter as the washers 4 and I and has a bore therethrough for telescoping it over the shaft 2. The lower face of the hub l4 rests upon the. upper face of the cushioning washer I 'and is provided with diametrically aligned clutch recesses lS-IS, the sides of whichare tapered to substantially coincide with the inclined sides 12-42 of the clutch teeth ll.

In the operation of the embodiment .of my housing I is operated to turn the shaft 2, the pin 3 on the shaft engages the lugs i6 and turns the washer '4, which in turn, by means of the teeth iii-Ill in the perforations 8-4, turns the cushioning washer 1 and it in turn, by means of the clutch teeth H and clutch recesses l2, turns the hub l4 and through it the turntable l3.

Vibrations in general in the shaft 2 are absorbed, before reaching the huh I! and turntable l3, by the cushioning washer 9. Rotational or torque irregularities and undulations are absorbed partly by the friction between the cushioning washer 1 and the lower end of "the hub ll resting thereon and partly by the toothed engagement of the cushioning washer I with the hub I4.

The tooth-and-recess engagement at l2-l6 provides a positive drive for the turntable from the shaft 2, but 'at the same time a yielding or cushioned drive.

By sloping the faces 12 of the rubber clutch tooth H and the corresponding faces of the recesses it, there will be a maximum amount of torque at which the turntable l3 will be lifted and the clutch tooth II will ride thereunder. ,This slipping amount of torque may be predetermined to be far in excess of that required to normally drive the turntable at any time, but provides for slipping of the drive, so that if a careless operator should by hand give a powerful spinning movement to the turntable, the force of such spinning movement will not be transmitted through the shaft to the gearing and to the motor and cause undue wear or injury thereto.

In the embodiment illustrated, the cushioning washer 1 is drivenby the teeth It and perforations 9. If desired, the teeth 9 and the perforations may be omitted and the cushioning washer I secured to the upper side of the disc 4 in the position illustrated by vulcanizing or by any suitable adhesive.

My invention is not limited to the exact details of construction shown and described. Changes and modifications may be made within the spirit 01' my invention without sacrificing its advantages and within the scope of the appended claims.

I claim: V

1. In a phonograph mechanism of the type comprising a vertical drive shaft and a turntable having a hub telescoped over the shaft, a support and drive for the hub comprising a pin v extending through the shaft, a metal disc telescoped on the shaft resting on the pin, a tooth on the disc engaged by the pin to rotatethe disc with the shaft, a rubber washer telescoped on the shaft and resting on the metal disc, mutual inter-engaging means on the disc and washer whereby the washer will be rotated with the disc, the hub resting on the rubber washer, a pair of opposite toothed recesses in the hub and a pair of rubber teeth integral with the rubber washer projecting into the toothed recesses.

2. A mechanism as described in claim 1 and in which the toothed recesses have opposite upwardly converging faces permitting disengage: ment of the hub and washer by a torque action overcoming the weight of the parts supported by the washer.

3. In a phonograph mechanism of the type comprising a vertical drive'shaft and a turntable telescoped over the shaft, a support on the shaft for the turntable, and means .to rotate the turntable by the shaft comprising mutually engaged projection and recess means, one on the support and the other on the turntable and one composed of rubber or like cushioning material, and said projection and recess means being disengageable upon the occurrence of a torque action overcoming the weight of the turntable.

4.In a phonograph mechanism of the type comprising a vertical drive shaft and a turntable telescoped overthe shaft, a support on the shaft for the turntable, and means to rotate the turntable by the shaft comprising mutually engaged WILLIAM A. .SCHMITIGEN.

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