The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 26, 1978
Filed:
Dec. 09, 1977
Teruo Houshi, Oota, JP;
Sanyo Electric Co., Ltd., Moriguchi, JP;
Toyko Sanyo Electric Co., Ltd., Oora, Gunma, JP;
Abstract
An apparatus for rotatively driving a turn table comprising a motor including a rotor having an arrangement of a plurality of permanent magnet poles such that north and the south poles are alternately disposed in a circle on the turn table and a stator provided to be opposed to the arrangement of the permanent magnet poles and including three stator pole means for electromagnetically driving the rotor, three saturable core coils provided to be opposed to the rotor and disposed to bring about a phase difference of 120.degree. from each other with respect to the arrangement of the rotor magnet poles, an oscillator for providing a predetermined frequency signal, three amplitude modulators for amplitude modulating the oscillator signal as a function of the inductance value of the corresponding saturable core coils which varies in association with the revolution of the turn table, a diode for demodulating the amplitude modulated outputs of each of the modulators, an amplifier for amplifying each of the corresponding amplitude demodulated signals and supplying the same to one end of the corresponding drive coils of the stator pole means, and a feedback resistor coupled to the other end of each of the drive coils of the stator pole means, the other end of each of the feedback resistors being commonly connected.