HYDRAULIC DRIVE DEVICE FOR TRAVELING WORK MACHINE

Title:

HYDRAULIC DRIVE DEVICE FOR TRAVELING WORK MACHINE

Document Type and Number:

WIPO Patent Application WO/2020/066483

Kind Code:

A1

Abstract:

Provided is a hydraulic drive device capable of a suitable hydraulic fluid supply when a traveling body of a work machine slips. The hydraulic drive device comprises a specific work actuator (27) that causes a work arm to perform a travel assist action during a slip; first and second travel motors (25R, 25L); first and second hydraulic pumps (31, 32); a travel switch valve (39) capable of switching between a neutral position (PN) and a travel straight position (PS); a communication throttle (39b) provided to a communication path through which a travel oil path and a work oil path in the travel straight position communicate; and a switch control unit (50) that switches the travel switch valve (39) to the neutral position (PN) when an independent operative action is carried out, and switches the travel switch valve (39) to the travel straight position (PS) when a specific combined operative action is carried out in which a forward travel operation and a specific work operation are performed simultaneously. The switch control unit (50) adjusts the opening degree of the communication throttle (39b) so as to commensurately reduce the flow rate in a communication path (39c) as the difference between a first pump pressure and a second pump pressure increases.

Inventors:

UEDA KOJI

Application Number:

PCT/JP2019/034476

Publication Date:

April 02, 2020

Filing Date:

September 02, 2019

Export Citation:

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Assignee:

KOBELCO CONSTR MACH CO LTD (JP)

International Classes:

F15B11/02; E02F9/22; F15B11/17

Foreign References:

JPH1150494A	1999-02-23
JPH0560236A	1993-03-09
JP2000017693A	2000-01-18
JP2000017693A	2000-01-18

Other References: