| 摘要 |
<p>PURPOSE:To conduct speed change operation quickly and comfortably by providing control means for automatically changing a characteristic of a pressure regulating mechanism disposed in a pressure oil supply path to a speed change hydraulic clutch according to propulsion load information before speed change. CONSTITUTION:A highpass valve 19 for opening a spool 19A by pressure to a hydraulic clutch C, a lowpass valve 20 for closing a spool 20A and an orifice are integrated in parallel connecting state into a case 22. An urging force changing mechanism 23 is adapted to change and regulate pressure for opening and closing the spools of the highpass valve 19 and the lowpass valve 20 through a rotary shaft 27, eccentric cams 28A, B and rods 24, 25 by a driving motor 37. Further, the driving motor 37 is controlled by control means for computing various kinds of sensor signals according to the use condition. Accordingly, control conformable to running condition can be conducted to accomplish quick and comfortable speed change operation correctly and with small work.</p> |
