Title:
HYDRAULIC CIRCUIT FOR DRIVING INERTIAL MASS
Document Type and Number:
Japanese Patent JPS5839805
Kind Code:
A
Abstract:
PURPOSE:To prevent the occurrence of abnormally high pressure in a hydraulic circuit for driving inertial mass such as a hydraulic shovel's swinger, by providing pipe passage maximum pressure setting means between an actuator for driving the inertial mass and changeover valves for controlling the actuator. CONSTITUTION:When the swinger of a hydraulic shovel or the like is to be driven by the hydraulic motor 1 of a hydraulic circuit, a changeover valve 4 is shifted to a position B1 to supply pressurized oil from a hydraulic pump 3 to the motor through pipe passages 6, 10, 18. When an arm or the like is to be driven by a hydraulic cylinder 2, another changeover valve 5 is shifted to a position B2. A relief valve 31 for setting the maximum pressure of the pipe passage 18 is provided in a pipe passage 32 for connecting the passage 18 and a tank communication pipe passage 13 to each other. Another relief valve 33 for setting the maximum pressure of a pipe passage 19 is provided in another pipe passage 34 for connecting the pipe passages 19, 13 to each other. The set pressure levels of the relief valves 31, 33 are made slightly higher than those of other relief valves 20, 22.
Inventors:
TANAKA HIDEAKI
Application Number:
JP13838881A
Publication Date:
March 08, 1983
Filing Date:
September 04, 1981
Export Citation:
Assignee:
HITACHI CONSTRUCTION MACHINERY
International Classes:
E02F9/22; F15B11/16; (IPC1-7): E02F9/22
Domestic Patent References:
| JP55067249B |
Attorney, Agent or Firm:
Kenjiro Take