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:
Apr. 01, 1997
Filed:
Dec. 20, 1995
Hideo Furukawa, Wako, JP;
Tatsuyuki Ohashi, Wako, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A hydraulic pressure control system for a frictional engagement element such as clutches for a vehicle automatic transmission. The engagement state of the clutches, i.e., the normality of clutch state or operation is discriminated by detecting the degree of clutch engagement (clutch slippage), specifically by calculating a ratio between the input rotational speed and the output rotational speed, and by comparing the calculated ratio with the gear ratio designated by the shift command at that time. When the clutch is found to be normal, the hydraulic pressures on the releasing and engaging clutches are controlled for temporarily bringing the total torque transferred by the two clutches below the transmission input torque, i.e., for reducing the co-engagement amount to the required minimum. On the other hand, when it is ascertained that the clutch is not normal, the hydraulic pressures of the two clutches are controlled in a conventional manner.