| 摘要 |
PURPOSE:To increase durability of solenoid valves, by directly supplying the oil pressure from a hydraulic pressure source to the hydraulic servo of an input pulley via a shift sequence mechanism and an input pulley modulator valve mechanism not through a speed reduction ratio control valve at steady running operation of a speed changer. CONSTITUTION:The oil pressure from a hydraulic pressure source 20 is directly supplied to the hydraulic servo of an input pulley 150 in a V-belt type stepless speed changer 140 at its steady running operation via a shift sequence mechanism 60 and an input pulley modulator valve mechanism 66 not through a speed reduction ratio control valve 51 operated by upshift and downshift solenoid valves 55, 56. Accordingly, a speed, at which driving power of an engine in each throttle opening is balanced with running resistance on the fixed land, is obtained, and its necessary hydraulic servo pressure of the input pulley is supplied from tne input pulley modulator valve mechanism, causing a number of on-off operating times of the solenoid valves 55, 56 to decrease at steady running and downshift maintaining time of a speed reduction ratio control mechanism, thus durability and reliability of the valve can be improved. |
