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. 09, 1999
Filed:
Dec. 30, 1996
Aisin AW Co., Ltd., , JP;
Abstract
A pressure regulating valve in a hydraulic control system for an automatic transmission according including a pressure regulating unit having a spool made slidable in a valve sleeve 10. An electromagnetic unit for causing a hollow core (or stator) is provided to attract a plunger (or movable element) arranged on a push rod communicating with the spool. The spool is moved by a spool moving mechanism in a direction to increase the flow from an input port to an output port to thereby raise an output pressure from an output port when the output pressure is lowered by a leakage. The spool position is controlled to control the output pressure in accordance with a balance among a spring force of spring means fitted in the valve sleeve, a feedback force resulting from the output pressure, and an electromagnetic attraction to be established in response to an electric signal provided to the electromagnetic unit having the hollow core and the plunger. In another embodiment, an input pressure feedback port is provided in the valve sleeve, and spool position control is additionally dependent upon an input pressure feedback force provided to the input pressure feedback port.