HYDRAULIC DRIVE DEVICE FOR CONSTRUCTION MACHINERY - HITACHI CONSTRUCTION MACHINERY

Title:

HYDRAULIC DRIVE DEVICE FOR CONSTRUCTION MACHINERY

Document Type and Number:

WIPO Patent Application WO/2014/192458

Kind Code:

A1

Abstract:

The purpose of the present invention is to limit wasted energy consumption due to throttled pressure loss of pressure compensated valve during combined operation in which two actuators with large maximum required flows are driven simultaneously, while also responding flexibly to the various flow balances required by the two actuators. When the required flow of a boom cylinder (3a) is smaller than a specified flow, the boom cylinder (3a) is driven by only the pressure oil discharged from a single flow-type main pump (202), and when larger than the specified flow, is driven by merging said pressure oil with the pressure oil discharged from the first discharge port (102a) of a split flow-type main pump (201). When the required flow of an arm cylinder (3b) is smaller than a specified flow, the arm cylinder (3b) is driven by only the pressure oil discharged from the second discharge port (102b) of a split flow-type main pump (102), and when larger than the specified flow, is driven by merging the pressure oils discharged from both the first and second discharge ports (102a, 102b).

Inventors:

TAKAHASHI KIWAMU (JP)
TSURUGA YASUTAKA (JP)
TAKEBAYASHI YOSHIFUMI (JP)
MORI KAZUSHIGE (JP)
NAKAMURA NATSUKI (JP)

Application Number:

PCT/JP2014/061205

Publication Date:

December 04, 2014

Filing Date:

April 21, 2014

Export Citation:

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Assignee:

HITACHI CONSTRUCTION MACHINERY (JP)

International Classes:

F15B11/02; E02F9/22; F15B11/17; F15B11/00

Foreign References:

JP2002206256A	2002-07-26
JP2008082521A	2008-04-10
JPH03260401A	1991-11-20
JP2011196438A	2011-10-06
JP2012067459A	2012-04-05

Other References: