Hydraulic circuit for automatic transmission having area controlled shift actuator valve with flow force compensation

• Main Author: MILLS DAVID C
• Format: Patent
• Language: English
• Published: 12.08.2014
• Subjects: ACTUATING-FLOATS; BLASTING; COCKS; DEVICES FOR VENTING OR AERATING; ENGINEERING ELEMENTS AND UNITS; GEARING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HEATING; LIGHTING; MECHANICAL ENGINEERING; TAPS; TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; THERMAL INSULATION IN GENERAL; VALVES; WEAPONS

A hydraulic circuit (88) for an automatic transmission (10) that employs a shift actuation valve (96) that controls the actuation of the synchronizer (29) for selectively controlling gear engagement. The shift actuation valve (96) includes a valve member (114) having at least one valve element (122) with an outer diameter (162) and a metering face (164). The metering face (164) is adapted to control the flow of pressurized fluid between an inlet (108) and an outlet (110) of the valve body (102). The metering face (164) includes a flow force compensating annular void (166) disposed adjacent the outer diameter (162) and that is defined by a lead angle α measured between the outer diameter (162) and a line intersecting the outer diameter (162) and tangential to the annular void (166). A solenoid (104) is employed to move the valve member (114) between predetermined positions.