HYDRAULIC CIRCUIT FOR CONSTRUCTION MACHINES

• Main Authors: SON, YOUNG-JIN, YUN, SEONG-GEUN
• Format: Patent
• Language: English; French; German
• Published: 21.10.2015
• Subjects: BLASTING; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR; DREDGING; FIXED CONSTRUCTIONS; FLUID-PRESSURE ACTUATORS; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; FOUNDATIONS; HEATING; HYDRAULIC ENGINEERING; HYDRAULICS OR PNEUMATICS IN GENERAL; LIGHTING; MECHANICAL ENGINEERING; SOIL SHIFTING; SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; WEAPONS

A hydraulic circuit for a construction machine is disclosed, which increases the temperature of hydraulic fluid up to an appropriate level for equipment operation even in a state where an operator does not sit on an operator's seat before starting working during the winter season or the like. The hydraulic circuit for a construction machine includes first and second hydraulic pumps and a pilot pump, a first hydraulic actuator connected to the first hydraulic pump through a first center bypass path, a second hydraulic actuator connected to the second hydraulic pump through a second center bypass path, an operation lever, a main control valve controlling flow directions of the hydraulic fluid supplied from the first and second hydraulic pumps to the first and second hydraulic actuators, respectively, first and second center bypass valves installed to be opened and closed on downstream sides of the first and second center bypass paths in the main control valve, and a switching valve installed to be opened and closed in a signal path between the pilot pump and the first and second center bypass valves.