HYDRAULIC DEVICE FOR STEPLESS TRANSMISSION

摘要

A hydraulic device is provided with a switching valve (1140) located at a portion which is upstream of a primary regulator (1110) and is downstream of that position of a sub-path (1105) to which a first bypass path (1117) is connected. The switching valve (1140) is switched between an interrupting state in which supply of hydraulic oil to that portion of the sub-path (1105) which is downstream of the switching valve (1140) is interrupted and an interconnecting state in which supply of the hydraulic oil to that portion of the sub-path (1105) which is downstream of the switching valve (1140) is permitted. In the hydraulic device, when the switching valve (1140) is being switched to the interconnecting state, a first check valve (1118) is closed as the discharge capacity of a main pump (1102) is increased, causing the supply route of the hydraulic oil discharged from a sub-pump (1103) to be automatically switched according to the discharge capacity of the main pump (1102). On the other hand, when the switching valve (1140) is being switched to the interrupting state, the first check valve (1118) is opened, causing the hydraulic oil discharged from the sub-pump (1103) to be introduced into a main path (1104).