Title:
MOTOR DRIVE CIRCUIT
Document Type and Number:
Japanese Patent JPS5821002
Kind Code:
A
Abstract:
PURPOSE:To prevent the abnormal rise in pressure at the time of additional acceleration, by providing a pressure control valve in a circuit connected between a tank and a supply/discharge circuit which connects a counterbalance valve and a directional control valve, so that the pressure control valve acts for a prescribed time. CONSTITUTION:When a directional control valve 4 is shifted to an operating position 4b, the pressure of oil from a pump 1 changes a counterbalance valve 7 to a left-hand position and the oil enters into the port 6a of a motor 6 and the oil from its other port 6b returns to a tank 2 so that the motor is driven. When the directional control valve 4 is returned to a neutral position and the driving of the motor 6 is stopped, the motor continues to rotate, because of the inertial force of the load, to perform pumping action. When the motor 6 is additionally accelerated by temporarily shifting the directional control valve 4 again to the operating position, a pressure control valve 14 keeps the pressure of an oil supply line 11a low for a response lag time to the shifting of the counterbalance valve 7 to an operating position, to avoid the enclosure of pressure between the valve 7 and the motor to prevent the abnormal rise in the pressure of the supply and the return lines.
Inventors:
MATSUNAGA CHIHARU
Application Number:
JP11794281A
Publication Date:
February 07, 1983
Filing Date:
July 28, 1981
Export Citation:
Assignee:
TOSHIBA MACHINE CO LTD
International Classes:
F15B11/00; (IPC1-7): F15B11/00