| 摘要 |
<p>PURPOSE: To speedily secure oil supply to a clutch and initially set pressure of transmission. CONSTITUTION: First and second input ports 4, 5 respectively connected with a solenoid valve 3 and a hydraulic pressure supply source PL in a changeover valve 2 are alternately changed over with each other by moving a spool 10. An orifice 8 is arranged between an output port 6 and a clutch 7. An upstream side of the orifice is communicated with one end of the spool through a second oil passage 15, while a downstream side of the orifice is communicated with the other end of the spool through a third oil passage 16. When oil is flowed through the solenoid valve 3 and the first input port due to starting of transmission, the spool is moved downward by the pressure on the upstream side of the orifice. The oil is flowed from the hydraulic pressure source through the second input port. After completion of oil supply to the clutch, pressure difference with respect to the orifice is reduced and the spool is moved in the opposite direction by a return spring 13, for opening the first input port. The clutch is controlled by a pressure control valve with an intially set pressure immediately after completion of oil supply.</p> |
