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:
Oct. 31, 2006
Filed:
Oct. 29, 2004
Seiichi Kinugasa, Anjo, JP;
Masanori Onoda, Anjo, JP;
Kazuhito Enomoto, Anjo, JP;
Kiyotomo Miura, Anjo, JP;
Naoyuki Fukaya, Anjo, JP;
Satoru Wakuta, Anjo, JP;
Masatoshi Adachi, Toyota, JP;
Akira Murakami, Toyota, JP;
Seiichi Kinugasa, Anjo, JP;
Masanori Onoda, Anjo, JP;
Kazuhito Enomoto, Anjo, JP;
Kiyotomo Miura, Anjo, JP;
Naoyuki Fukaya, Anjo, JP;
Satoru Wakuta, Anjo, JP;
Masatoshi Adachi, Toyota, JP;
Akira Murakami, Toyota, JP;
Aisin AW Co., LTD, Aichi-ken, JP;
Toyota Jidosha Kabushiki Kaisha, Aichi-ken, JP;
Abstract
A failsafe hydraulic circuit designed to avoid simultaneous engagement of two friction engagement elements (e.g., clutches, brakes, etc.) incorporated in a speed change apparatus of a motor vehicle or the like. If a first failsafe valve is in the open position state and a first engaging pressure is supplied to a first hydraulic servo via the first failsafe valve, the first engaging pressure is also input to a first oil pressure switch via a second failsafe valve being in the closed position state. Therefore, using the first oil pressure switch, it can be detected that the first engaging pressure is supplied to the first hydraulic servo. Furthermore, if the first engaging pressure is, for example, greater than the set pressure of the first oil pressure switch, this situation can also be detected. Such detections provide confirmation of normal operation of the first failsafe valve and the second failsafe valve.