HYDRAULIC DRIVE DEVICE FOR CONSTRUCTION MACHINE

• Main Authors: NAKAMURA YUTA, KAYANE MASAHIRO, ICHIMURA KAZUHIRO, KODAKA KATSUAKI
• Format: Patent
• Language: English; Korean
• Published: 31.12.2013
• 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

[Problem] To permit guiding oil of a high pressure in an oil passage section, which communicates a valve device and a filter to each other, to a relief valve by a relatively inexpensive structure even when clogging occurs in a filter arranged in an oil passage communicating the valve device and the relief valve to each other. [Solution] A hydraulic pump (20) and a charge valve (25), to which pressure oil is fed from the hydraulic pump (20) via an oil passage (26), are arranged. Arranged in the charge valve (25) are a valve device, for example, an on/off valve (33) switchable according to pressure oil delivered from the hydraulic pump (20), a relief valve (34) specifying a maximum of switching pressure for the on/off valve (33), and a filter (36) arranged in an oil passage (35) communicating the on/off valve (33) and the relief valve (34) to each other. In the oil passage (35), a check valve (37) is arranged in parallel with the filter (36) such that a flow of pressure oil from a side of the on/off valve (33) toward a side of the relief valve (34) is allowed but a flow of pressure oil from the side of the relief valve (34) toward the side of the on/off valve (33) is prevented.