Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
HYDRAULIC PRESSURE REGENERATING DEVICE
Document Type and Number:
Japanese Patent JP2000110803
Kind Code:
A
Abstract:

To prevent breating when a motor is at low speed.

A shuttle valve 45 detects pilot pressure Pb1 or Pb2 generated by an operation lever device 53 for a boom. A pressure sensor 46 converts the pressure detected by the shuttle valve 45 into an electric signal. A controller 100 receives the signal from the pressure sensor 46 and a signal from a throttle volume 61. The controller 100 provides a solenoid proportional pressure reducing valve 43 with a drive current (i) to control a regenerating selector valve 42 toward the closing direction for regenerating return oil whose amount is proportional to the decrease of an engine speed if an arm is operated independently only through an operation lever device 52 for the arm when a reference engine speed (r) is lower than a nominal speed.


Inventors:
Ishikawa, Hiroji
Toyooka, Tsukasa
Nakamura, Tsuyoshi
Tomikawa, Osamu
Application Number:
JP1998000282289
Publication Date:
April 18, 2000
Filing Date:
October 05, 1998
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
HITACHI CONSTR MACH CO LTD
International Classes:
E02F9/22; F15B11/00; F15B11/16; (IPC1-7): F15B11/16; E02F9/22; F15B11/00
Attorney, Agent or Firm:
春日 讓



 
Previous Patent: CYLINDER POSITION CONTROLLER

Next Patent: HYDRAULIC CONTROL VALVE