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. 31, 1990
Filed:
Dec. 24, 1987
Takashi Iino, Saitama, JP;
Yoshihiro Katagiri, Saitama, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A hydraulically operated continuously variable automotive transmission includes a transmission ratio controlling member and a hydraulic actuator operatively coupled to the transmission ratio controlling member for continuously operating the transmission ratio controlling member to increase or reduce the transmission ratio of the continuously variable automotive transmission. A control valve is provided for applying a controlling hydraulic pressure to the hydraulic actuator dependent on the difference between a first control force commensurate with an indication of the automobile driver's intention of acceleration or deceleration and a second force commensurate with the engine rotational speed, in order to change the direction in which the hydraulic actuator is operated. The control valve includes, but is not limited to, a cylinder having two ports communicating with the hydraulic actuator, a port communicating with a source of hydraulic pressure, and a port communicating with an oil tank, a first spool slidably disposed in the cylinder and slidable dependent on the difference between the first and second control forces for selectively bringing the ports into and out of communication, a second spool slidably disposed in the first spool and movable in response to a control force commensurate with a control signal, and variable restrictions disposed between the first and second spools for varying the amount of controlling hydraulic pressure applied to the hydraulic actuator.