HYDRAULIC CONTROL DEVICE FOR AUTOMATIC TRANSMISSION

• Main Authors: YOSHIOKA YUHEI, MIYAMOTO NOBUHIKO, ISHIKAWA KAZUNORI, HYODO YOSHIMITSU, TSUCHIDA KENICHI
• Format: Patent
• Language: English
• Published: 30.06.2014
• Subjects: BLASTING; ENGINEERING ELEMENTS AND UNITS; GEARING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MECHANICAL ENGINEERING; THERMAL INSULATION IN GENERAL; WEAPONS

PROBLEM TO BE SOLVED: To provide a hydraulic control device for an automatic transmission, which can be more simply constructed to hydraulically control a friction engaging element to be controlled to engage in a predetermined state of a forward stage or in a stage of a reverse stage, while discharging a hydraulic pressure from a hydraulic servo of the friction engaging element via an orifice when discharging a reverse range pressure or quickly when discharging a forward range pressure.SOLUTION: A B-4 control valve 37 includes: an input port 37g communicated with a forward range pressure output port 25b; an input port 37e for inputting a reverse range pressure Pwhile bypassing an orifice 71, and for discharging the reverse range pressure Pwhile passing through the orifice 71; an output port 37f communicated with a hydraulic servo 56 of a fourth brake B-4, and communicated with the input port 37g when located at a left half position and communicated with the input port 37e when located at a right half position; a communication port 37d communicated with the output port 37f when located at an intermediate position; and a communication port 37c communicated with the communication port 37d when located at the intermediate position, for discharging hydraulic pressure, not via the orifice 71.