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:
Mar. 24, 2015
Filed:
Feb. 05, 2014
Hitachi Automotive Systems, Ltd., Hitachinaka-shi, Ibaraki, JP;
Ryo Tadokoro, Atsugi, JP;
Shinichi Kawada, Isehara, JP;
Atsushi Yamanaka, Atsugi, JP;
Hiroyuki Nemoto, Hitachi, JP;
Hitachi Automotive Systems, Ltd., Ibaraki, JP;
Abstract
In a valve timing control system of an internal combustion engine employing both an electric-motor-driven intake valve timing control device for changing intake valve timing and an electric-motor-driven exhaust valve timing control device for changing exhaust valve timing, the intake valve timing control device includes a less-friction roller speed reducer having a toothed gear and configured to transmit torque by repeated relocations of each of rollers rolling and relocating from one of two adjacent teeth of the toothed gear to the other. In contrast, the exhaust valve timing control device includes a planetary-gear speed reducer having a friction greater than a friction of the roller speed reducer and configured to transmit torque by meshed-engagement of toothed gears in mesh with each other.