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:
May. 22, 2012
Filed:
Sep. 25, 2009
Tetsuya Shimizu, Anjo, JP;
Kenichi Tsuchida, Hazagun, JP;
Akitomo Suzuki, Anjo, JP;
Kazunori Ishikawa, Toyota, JP;
Tetsuya Shimizu, Anjo, JP;
Kenichi Tsuchida, Hazagun, JP;
Akitomo Suzuki, Anjo, JP;
Kazunori Ishikawa, Toyota, JP;
Aisin AW Co., Ltd., Anjo, JP;
Abstract
A hydraulic control apparatus for an automatic transmission includes a first solenoid valve, a second solenoid valve, a third solenoid valve, a preliminary shift speed switch valve, and an oil pressure supply switch valve, which is switched between a normal-state position where the first, second, and third working fluid pressures can be supplied to the hydraulic servos of the first, second, and third friction engagement elements, respectively, and a failure-state position where the first and second preliminary oil pressures can be supplied to the hydraulic servos of the first and second friction engagement elements, respectively, and a line pressure can be supplied to the hydraulic servo of the third friction engagement element, during a failure that causes de-energization.