JPS5774804A - Turntable device - Google Patents

Abstract

PURPOSE: To obtain a turntable device which is flat and light, by providing a magnet bodies which are placed symmetrically on the inside surface of a turntable of a record player, and are magnetized to the opposite polarity alternately, providing plural coils on corresponding positions on a fixed substrate, and driving them.

CONSTITUTION: On the upper surface of a fixed substrate 1 on which a hub 2 and a hollowed place 2a are formed, a doughnut-like insurating plate 3 is stuck at a position with the hub 2 between, and on the insulating plate 3, coils S1W3 of an almost same shape are printed and arranged at almost equal intervals to the center and also at equal intervals to each other. On the insulating plate 3 positioned between each S1W3, position detectors V1W3, for instance, Hall elements are placed. Also, a turntable 9 which is placed so as to be opposed to the coils S1W3 is supported by a shaft 7, and on the inside surface, magnet bodies R1W4 which are printed on a thin ring-like synthetic resin body 10 and are magnetized and arrayed to the opposite polarity alternately are placed so as to correspond to the coils S1W3. A DC current supplied to the coils S1W3 is controlled by outputs of the detectors V1W3, and a speed of rotation of the turntable 9 is controlled.

COPYRIGHT: (C)1982,JPO&Japio