| 摘要 |
<p>PURPOSE:To improve responsiveness of a reduction ratio control valve at the time of down shifting and to enable rapid down shifting, by giving a load by a spring in a moving direction of a spool at the time of the down shifting. CONSTITUTION:At the time of down shifting a solenoid valve 85 is turned on and a hydraulic oil chamber 816 is decompressed. A spool 812 is moved rapidly to the left by a load of a spring 811 and line pressure of a hydraulic oil chamber 815, a hydraulic oil duct 2 is connected with a drain port 814 for decompression and an input pulley is actuated rapidlly in an expanding direction to increase a torque ratio. As a solenoid valve 84 is turned on and the hydraulic oil chamber 815 is decompressed at the time of up shifting, the spool 812 is moved to the right, line pressure of a hydraulic oil duct 1 is supplied to the hydraulic oil duct 2 which results in actuation of an input pulley in a closing direction and a decrease of the torque ratio.</p> |
