US2440420A

US2440420A - Control mechanism for sound reproducing

Info

Publication number: US2440420A
Application number: US523384A
Authority: US
Inventors: Fred Van Eps
Original assignee: Individual
Current assignee: Individual
Priority date: 1944-02-22
Filing date: 1944-02-22
Publication date: 1948-04-27
Anticipated expiration: 1965-04-27

Description

April 27, 1948'. r F. VAN EPs 2,440,420

- CONTROL MECHANISM FOR SOUND REPRODUCING 7 Filed Feb. 22; 1944 INVENTOR. Fred 7 3292 E708 i k% wv Patented Apr. 27, 1948 CONTROL MECHANISM FOR SOUND V I REPRODUCING l I Fred Van Eps, Plainfield, N. J. Application February 22, 1944, Serial No. 523,384 (o1. 274-1)" 10 Claims.

The invention relates to a control mechanism or control device for sound reproducing apparatus for phonograph records and the like and more particularly to a control mechanism for sound reproducing means having a turntable associated therewith and by means of which selected portions of the sound record may be played or de leted at will.

In the use of phonographs and other sound reproducing apparatus it is often desirable to stop the reproduction at a precise point of the sound track for the purpose of copying, recording I or broadcasting of selected portions of the records. Heretofore, this has been accomplished by disengaging the pickup mechanism from the sound track at the selected point and then again bringing it into engagement with the other portions of the record to be played or reproduced.

I It has been found very difiicult to make accurate reproductions or deletions with this type of arrangement for the reasonthat it is almost impossible to reengage the jewel point at the precise point of the sound track once it has been raised from the record. ,This can readily be understood from the fact that the average commercial record usually has 120 to 150 grooves to an inch. Thus the replacement of the point of necessity becomes somewhat'haphazard, and if the record is kept revolving with the turntable, accurate reproduction or deletions becomes next to impossible. On the other hand, if the record is stopped from revolving together with the tumtable, a swishing sound will be heard when the turntable is again started for the reason that it takes at least one revolution to build up proper reproduction speed.

For this and other reasons it has been found impractical to do any copying or recording by using this type of control mechanism.

It is, therefore, among the objects of the present invention to provide a, control device by means of which the reproduction may be stopped instantaneously at any point of the sound track without disengaging the point of stylus from the sound grooves.

Another object is to'provide a stop device for the record without stopping the rotation of the turntable. V

A further general object is to providea device ofthe character described which will perform efiiciently the purpose for which it is intended; which is simple and economical of construction; which can be manipulated expeditiously, conveniently and safely with accuracy and which easily can be assembled and installed on a conventional sound reproducing apparatus.

Other objects and advantages inherent in the invention will become apparent from the following description and accompanying drawing which disclose by way of example an embodiment of the invention.

In the drawing:

Figure 1 is a top plan view of a;phonograph table showing the device of the invention mounted thereon. v

Figure 2 is a fragmentary top plan view of the device drawn to an enlarged scale.

Figure 3 is a section taken along the line 3-3 of Figure 2, and i Figure 4 is a section taken along the line 4-4 of Figure 2.

Referring in greater detail to the drawinathe phonograph table or base I0 is provided with a conventional felt covered rotatable turntable H, which supports a disc record It.

Pivotally mounted on the table In is "the playing arm or tone arm [3 having at its free end a pickup mechanism l4, 7

The turntable is provided with a-central pivot I5 over which the record l2 his The rotation of the table is accomplished'by a motor or spring not shown in the drawing.

The pickup mechanism is of the usual wellknown construction and will not be described in detail herein. Operative engagement of the pickup mechanism with the sound track of the record is brought about by a needle or stylus of the conventional type (not shown in the drawing).

The stop device or control mechanism according to the invention comprises a plate [6 of steel or other magnetic material which is provided with a. hub ll fitting over the pivot I5 of the turntable II. One side of the plate is provided with a frictional covering Ilia, such as rubber, for engaging the ungrooved portion of the record [2.

This frictional covering should provide suiiicient frictional connection between the disc Hi, When arrested, and the record l2 to overcome the frictional drive connection between the turntable II and the record [2.

In this connection it might be remarked parenthetically that the conventional record has a central ungrooved portion which usually bears the title of the record and the manufacturer's identifying trade-mark or symbol.

It will be understood that due to the frictional contact between the record I2 andthe plate [6, the latter normally will rotate-with the record and the turntable. 5 i

netic device from said disc upon deenergization of said magnetic device.

6. Control mechanism for sound reproducing apparatus and the like employing a rotatable disc record, comprising a disc of magnetic material for mounting concentrically on thetop of the record, said disc having a driving connection with the central top surface portion of the record so that said disc normally will be rotated jointly with said record, a gimbals frame mounted above said disc, an electro-magnetic device supported in said gimbals frame for arresting the rotation of said disc and said record upon energization, and anti-magnetic means carried by said electromagnetic device for supporting it on said disc out of direct contact therewith.

7. Control mechanism for sound reproducing apparatus and the like employing a rotatable disc record, comprising a disc of magnetic material for mounting concentrically on the top of the record, said disc having a driving connection with the central top surface portion of the record so that said disc normally will be rotated jointly with said record, a gimbals frame mounted above said disc, an electro-magnetic device supported in said gimbals frame for arresting the rotation of said disc and said record upon energization, and spring means carried by said frame for urging said disc away from said electro-magnetic device.

8. Control mechanism for sound reproducing apparatus and the like employing a rotatable disc record, comprising a disc of magnetic material for mounting concentrically on the top of the record, said disc having a driving connection with the central top surface portion of the record so that said disc normally will be rotated jointly with said record, and a stationary magnetic device mounted above said disc upon the energization of said spring urged means for supporting said electro-magnetic device on said disc.

9. Control mechanism for sound reproducing apparatus and the like employing a rotatable disc record, comprising a disc of magnetic material for mounting concentrically on the top of the record. said disc having a driving connection with the central top surface portion of the record so that said disc normally will be rotated jointly with said record, a gimbals frame mounted above said disc, an electro-magnetic device supported in said gimbals frame for arresting the rotation of said disc upon energization, and spring urged means carried by said frame for supporting said electromagnetic device on said disc.

10. Control mechanism for the operation of apparatus for reproducing sound from sound records, comprising a rotatable turntable, a disc record frictionally engaging said turntable so as to be rotated thereby, electro-magnetically controlled means for arresting the rotation of said record without stopping the rotation of said turntable, said means comprising a disc of magnetic material concentric with said record having a frictional covering so as to provide suflicient frictional connection between said disc, when arrested, and said record to overcome the frictional drive connection between said turntable and said record.

FRED VAN EPS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,187,129 Bertolucci June 13, 1916 1,255,143 Ebeling Feb. 5, 1918 1,384,011 Cortella May 25, 1920 1,595,141 Cortella Aug. 10, 1926 1,798,196 Dyer Mar. 31, 1931 1,955,497 Harvey Apr. 17, 1934 2,093,862 Burhoe Sept. 21, 1937 2,278,680 Thompson Apr. 7, 1942 2,293,219 Rieber Aug, 18, 1942 FOREIGN PATENTS Number Country Date 19,667 Great Britain Aug. 28, 1912