| 摘要 |
PURPOSE:To reduce a cost of a hydraulic multiplier by communicating the inlet of the multiplier to the upper side of a flow rate control valve device and applying an oil pressure in a working chamber of the multiplier to force a spool of the flow control valve device so as to increase a discharged oil pressure of a hydraulic pump. CONSTITUTION:A flow control valve F/C involves a piston 44 and a spool 24 which is slidably fit inside a cylinder bore 23. A spring 47 is disposed between the spool 24 and the piston 44 and a chamber 46 as well, which is communicated with a passage 40 communicated with a power steering P/S. Due to a pressure difference between the chambers 32, 46, the spool 24 is moved right against the spring 47 so that the chamber 32 is connected to a passage 48 which is communicated with a reservoir R to restrain the pressure difference from a further increase. The input inlet 57 of a multiplier B is communicated with a hydraulic pump joint port 27 of the control valve F/C. Additionally, a working oil pressure chamber 59 of the multiplier B is communicated with an oil chamber 98 at the right side of the piston 44 via a passage 97. A pressure in the oil pressure chamber 59 is applied via the piston 44 to power the spool 24 so as to increase a discharged pressure of a pump. |
