| 摘要 |
PROBLEM TO BE SOLVED: To surely carry out the control of an opening and closing operation of a clutch valve. SOLUTION: The hydrostatic continuously-variable-transmission (CVT) carries out the continuously variable speed changing by connecting a hydraulic pump P and a hydraulic motor M via a closed hydraulic circuit, and by variably controlling the displacement of the hydraulic motor. Its clutch apparatus CL comprises a clutch valve (a valve composed of a valve spool 70) for communicating and intercepting a high pressure side hydraulic passage and a low pressure side hydraulic passage which compose the closed hydraulic circuit, a governor mechanism for generating a governor force corresponding to an input rotational speed of the hydraulic pump P, and for applying the governor force in the closing direction of the clutch valve, a spring 63 for applying an energizing force in the opening direction of the clutch valve, and a cushioning mechanism having a variable oil chamber 78a and an oil reservoir chamber 78b for cushioning the opening and closing motion of the clutch valve operated according to the governor force and the energizing force. COPYRIGHT: (C)2005,JPO&NCIPI |
