Title:
FLOW RATE CONTROLLER OF MULTIPLE FIXED DISPLACEMENT PUMP
Document Type and Number:
Japanese Patent JPS596405
Kind Code:
A
Abstract:
PURPOSE:To save energy by having at least one of a plurality of pumps operate according to variation in quantity of oil for an actuator by means of a relief valve and if the quantity required by it exceeds the capacity of oil supply by the pump, setting the pressure at the relief valve of each pump by means of sensors. CONSTITUTION:When pumps are driven with change-over valves 67 to 69 taking positions as shown in the drawing, a part of the oil discharged from the pump 31 flows back into a tank 57 so that the first relief valve 51 exhibits the same specified prssure Pm as that of the second relief valve 73. The oils discharged from the pumps 32 and 33 are returned into tanks 57 via the first relief valves 52 and 53, respectively. An actuator which is connected to a pipe line AC is operated and if the quantity of oil required by it exceeds the displacement of the pump 31, the pressure in a large diameter chamber 70 is reduced due to the pressure drop in a high pressure line 40 so that a staged piston 91 is moved left to set the pressure at the relief valve 51 maximum. A position sensor 109 is then actuated to switch a change-over valve 68 to take a position B, assuring the needed flow rate.
Inventors:
HATA KENTAROU
MIYAUCHI KOUJI
NISHIMUNE HISAAKI
MIYAUCHI KOUJI
NISHIMUNE HISAAKI
Application Number:
JP11579782A
Publication Date:
January 13, 1984
Filing Date:
July 02, 1982
Export Citation:
Assignee:
KAWASAKI HEAVY IND LTD
International Classes:
F04B49/00; F15B11/17; (IPC1-7): F04B49/00; F15B11/16
Attorney, Agent or Firm:
Kenzo Ota
Next Patent: JPS596406