Title:
CONSTRUCTION-MACHINERY HYDRAULIC CIRCUIT
Document Type and Number:
WIPO Patent Application WO/2020/031817
Kind Code:
A1
Abstract:
According to the present invention, left and right directional switching valves each have: a pump port that is connected to a pump; a first compensation port that is connected to an upstream side of a corresponding pressure compensation valve; a second compensation port that is connected to a downstream side of the corresponding pressure compensation valve; a pair of supply and discharge ports that are connected to a corresponding traveling motor; and a communication port. The communication ports of the left and right directional switching valves are connected to each other via a communication line. When a travel controller is operated to move a spool from a neutral position, the pump port is communicated with the first compensation port, and the second compensation port is communicated with one of the supply and discharge ports and with the communication port. The directional switching valves are each configured such that the degree of communication between the second compensation port and the communication port is increased as the amount of movement of the spool from the neutral position becomes larger.
Inventors:
AOKI SEIJI
TODE YOSHIYUKI
OHIRA MASAHIRO
NAKAJIMA HIDEKI
TODE YOSHIYUKI
OHIRA MASAHIRO
NAKAJIMA HIDEKI
Application Number:
PCT/JP2019/030114
Publication Date:
February 13, 2020
Filing Date:
August 01, 2019
Export Citation:
Assignee:
KAWASAKI HEAVY IND LTD (JP)
CATERPILLAR SARL (CH)
CATERPILLAR SARL (CH)
International Classes:
F15B11/16; B62D11/04; E02F9/22; F15B11/05
Foreign References:
| JP2015064024A | 2015-04-09 | |||
| JPH04261923A | 1992-09-17 | |||
| KR20050066038A | 2005-06-30 |
Attorney, Agent or Firm:
PATENT CORPORATE BODY ARCO PATENT OFFICE (JP)
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