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:
Aug. 23, 1988
Filed:
Jun. 25, 1987
Shigeki Saito, Katsuta, JP;
Masato Sakai, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An electric power steering apparatus comprises a steering shaft 34, a detector 27 for detecting an operation of the power steering apparatus, an electric motor 3 driven in response to an output of the detector 27 for generating an assisting force for a steering operation, and a reduction gear 1 including an input shaft 2 driven by the electric motor 3, an output shaft 13 connected to the steering shaft 34, and a planetary gear mechanism 36 for reducing the rotational speed of the input shaft 2 and transmitting the reduced rotational speed to the output shaft 13. The planetary gear mechanism 36 includes a sun gear 6 rotatable with the input shaft 2, a ring gear 8, planet gears 7 connected to the output shaft 13 and adapted to transmit revolving motion thereof around the sun gear 6 to the output shaft 13, and a gear case 18 for accommodating the sun gear 6, the ring gear 8, and the planet gear 7. As electromagnetic clutch 35 is accommodated in the gear case 18 and is switched over in response to the output of the detector 27 between a first position in which it locks the ring gear 8 unrotatably and a second position in which it releases the ring gear 8 to allow it to be rotatable with respect to the output shaft 13.