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:
Feb. 20, 2018
Filed:
Sep. 29, 2014
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, Aichi-ken, JP;
TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota, JP;
Abstract
A fitting clearance of a relief valve functions as an air bleeding orifice. When a discharge pressure reaches a relief pressure so that the relief valve turns into a relief state, a spool is moved so as to limit flow-out of hydraulic oil through the fitting clearance. As a result, generation of air trapping is suppressed by air bleeding function of the relief valve in a closed state. Air in a discharge oil passage is discharged quickly in the initial period of the startup of an electric oil pump, thereby improving rise-up of discharge pressure. During normal pump operation in which the relief valve is held in a relief state, pressure loss due to flow out of the hydraulic oil from the fitting clearance is suppressed and consequently, an electric oil pump having substantially the same discharge performance as conventionally can be used.