| 摘要 |
PROBLEM TO BE SOLVED: To relieve a shock at piston moving time by constituting a hydraulic servo mechanism to control a swash plate angle out of a solenoid valve and a manual swash plate angle control valve composed of a piston and a spool arranged on the inside, and controlling the swash plate angle by controlling a movement of the piston. SOLUTION: A hydraulic servo mechanism 61 changes a swash plate angle of a swash plate of a cradle type hydraulic pump by vertically moving a pin shaft 190 by vertically moving a piston 71 of a manual swash plate angle control valve by controlling a solenoid valve 73 in a switching system. In the piston 71, a spool 72 is slidingly fitted/installed on the inside so that the spool 72 is vertically moved by rotating a travel neutral cam 149 and a crank arm 159 through a shock absorbing spring 162 by rotation of a travel shift arm 151. Thus, shift in a traveling HST type continuously variable transmission mechanism can be lightly performed without a shock by rotating the swash plate by operating the piston 71 and the spool 72. |
