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:
Mar. 24, 2015
Filed:
Oct. 26, 2011
Tetsuya Shimizu, Anjo, JP;
Tomomi Ishikawa, Anjo, JP;
Tomoya Jinno, Anjo, JP;
Kenichi Tsuchida, Nishio, JP;
Kazunori Ishikawa, Toyota, JP;
Tetsuya Shimizu, Anjo, JP;
Tomomi Ishikawa, Anjo, JP;
Tomoya Jinno, Anjo, JP;
Kenichi Tsuchida, Nishio, JP;
Kazunori Ishikawa, Toyota, JP;
Aisin AW Co., Ltd., Anjo, JP;
Abstract
A power transmission device that transmits power from a motor to a wheel via a hydraulically driven friction engagement element and that includes a mechanical pump driven by the motor to produce a hydraulic pressure that is regulated by a pressure regulating valve; an electric pump that produces a hydraulic pressure; a switching mechanism that either switches an output pressure of the regulating valve or an output pressure of the electric pump to a servo of the engagement element based upon a signal pressure, and a drain valve that opens to drain oil when a hydraulic pressure of a preset pressure or more is applied, and the switching mechanism connects to the drain valve to allow communication between the electric pump and the drain valve in the first state, and shut off communication between the electric pump and the drain valve.