HYDRAULIC CIRCUIT STRUCTURE FOR HYDRAULICALLY CONTROLLED CLUTCH, TRANSMISSION

摘要

PURPOSE:To enhance the cooling efficiency of oil by providing a large capacity main pump and a small capacity sub-pump so as to constitute an oil pump assembly thereby reducing loss in the output of an engine which is consumed by the oil pump assembly. CONSTITUTION:In a hydraulic control circuit for a transmission, an oil pump assembly is composed of a large capacity main pump 1a and a small capacity sub-pump 1b. A pump change-over valve 41 is disposed between pressure oil discharge passages 44a, 44b from the main pump 1a and the sub-pump 1b and a supply passage 45 led to a clutch and the transmission and a passage 46 led to an oil cooler 40. An oil filter 43 is disposed in a suction side passage 47 led to both pumps 1a, 1b.