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:
Jul. 17, 1990
Filed:
Oct. 19, 1988
Hideo Koyama, Tokyo, JP;
Koji Sasajima, Tokyo, JP;
Kazuya Maki, Aichi, JP;
Kouji Yamaguchi, Saitama, JP;
Yoshikazu Ishikawa, Saitama, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A hydraulic continuously variable speed transmission with a direct clutch valve comprises a hydraulic pump, a hydraulic motor, a hydraulic closed circuit for hydraulically connecting the both, a direct clutch valve placed in the closed circuit, a speed reduction ratio control actuator, and a direct clutch valve controlling device for controlling operations of said direct clutch valve to block the closed circuit when the speed reduction ratio becomes substantially '1'. The direct clutch valve controlling device maintains a direct connecting state when an actual engine speed is higher than a direct clutch disconnecting reference engine speed at the speed reduction ratio of approximately '1'. Then, the direct clutch valve control device releases the blocking of the closed circuit by the direct valve when a drop of the actual engine speed from the direct clutch disconnecting reference engine speed exceeds a predetermined amount corresponding to the vehicle speed.