Hydraulic control apparatus for vehicular fluid- actuated power transmitting device provided with lock-up clutch

• Main Author: FUKUSHIMA HIROSHI,KATO NAOKI,TSUCHIDA KENICHI
• Format: Patent
• Language: English
• Published: 22.08.2007
• Subjects: BLASTING; ENGINEERING ELEMENTS AND UNITS; GEARING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MEASURING; MEASURING QUANTITY OF HEAT; MEASURING TEMPERATURE; MECHANICAL ENGINEERING; PHYSICS; TESTING; THERMAL INSULATION IN GENERAL; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR; WEAPONS

A hydraulic control apparatus for a vehicular fluid-actuated power transmitting device provided with a lock-up clutch and an oil cooler, the lock-up clutch being operable between an engaged state and a released state according to a difference between pressures of a working fluid in an engaging fluid chamber and a releasing fluid chamber, the oil cooler being connected to a fluid passage communicating with the engaging and releasing fluid chambers, and operable to cool the working fluid, the hydraulic control apparatus including an oil cooler by-pass valve operable to permit the working fluid to by-pass the oil cooler, and a low-temperature by-pass device operable to open the oil cooler by-pass valve, for permitting the working fluid to by-passes the oil cooler, when a temperature of the working fluid is lower than a predetermined lower limit.