Drive device with belt and stepped speed pulley
US4047721A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 16, 1976 |
| Grant date | Sep 13, 1977 |
| Priority date | — |
| Expiry date | Apr 16, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B19/18
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A record player drive, comprising a belt pulley concentrically disposed relative to and connected with a turntable, a motor having a motor shaft containing sections of different diameters, and a drive belt connecting the belt pulley with the motor shaft. A guide fork shifts the belt on the sections, and an operating element stepwise sets different turntable-rotational speeds. A holder keeps the operating element in positions corresponding to drive rotational speeds of the turntable, and an elastic coupling is disposed between the guide fork and the operating element for exerting a shifting force on the guide fork when the operating element is moved with blocked guide fork in another drive position. A switch opens and closes the motor electric circuit, and a blocking device blocks the shifting movement of the guide fork, and is coupled with the switch such that with opened electric circuit the blocking is operative and with closed electric circuit is inoperative.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.