To suppress driving belt slip when an engine is started by a simple circuit structure.
A primary pulley 20 is provided with hydraulic chambers P1, P2, and a secondary pulley 21 is provided with a hydraulic chamber S1. The hydraulic chamber S1 is connected to a secondary pressure passage 51 extending from an oil pump 50. A primary pressure passage 61 communicating with the hydraulic chamber P1 and a primary pressure passage 62 communicating with the hydraulic chamber P2 are connected to the secondary pressure passage 51. An oil passage opening/closing valve 68 opened/closed according to hydraulic pressure from the secondary pressure passage 51 is arranged in the primary pressure passage 62. When the engine is started from a state in which hydraulic fluid is led to flow out from the hydraulic chambers P1, P2, S1, the primary pressure passage 62 is disconnected by the oil passage opening/closing valve 68 until discharge pressure of the oil pump 50 is increased. Thereby, the hydraulic fluid is guided to the secondary pulley 21 without being consumed by the primary pulley 20 and clamp force of the secondary pulley 21 is rapidly increased.
OGAWA HIROSHI
| JP2005036820A | 2005-02-10 | |||
| JPH08219267A | 1996-08-27 | |||
| JP2005155897A | 2005-06-16 | |||
| JPH0428268A | 1992-01-30 |
| WO2006046849A1 | 2006-05-04 |
Yoshitaka Kozuka
Akiko Tsutsui