Title:
HYDRAULIC PRESSURE CONTROL CIRCUIT OF CONSTRUCTION MACHINE
Document Type and Number:
Japanese Patent JP2020094642
Kind Code:
A
Abstract:
To independently control a supply flow rate, an exhaust flow rate and a regeneration flow rate to a stick cylinder in a construction machine having first and second spool valves for sticks respectively connected to first and second hydraulic pressure pumps.SOLUTION: A poppet valve 20 for controlling a supply flow rate from a first hydraulic pressure pump 11 is provided on an upstream side of a first spool valve 18 for a stick, and the first spool valve for the stick is configured to supply oil to a stick cylinder 9 without limiting a flow rate from the poppet valve. During elongating the stick cylinder, the poppet valve controls the supply flow rate to a head side oil chamber 9a from the first hydraulic pressure pump, the first spool valve for the stick controls the regeneration flow rate to the head side oil chamber from a rod side oil chamber 9b, and a second spool valve 19 for a stick controls the supply flow rate to the head side oil chamber from the second hydraulic pressure pump 12 and the exhaust flow rate to an oil tank 15 from the rod side oil chamber.SELECTED DRAWING: Figure 2
Inventors:
NAKAJIMA HIDEKI
KIYASU KOICHI
KIYASU KOICHI
Application Number:
JP2018233210A
Publication Date:
June 18, 2020
Filing Date:
December 13, 2018
Export Citation:
Assignee:
CATERPILLAR SARL
International Classes:
F15B11/044; E02F9/22; F15B11/024; F15B11/17
Domestic Patent References:
| JP2010230060A | 2010-10-14 | |||
| JP2005221026A | 2005-08-18 | |||
| JP2019002531A | 2019-01-10 |
Foreign References:
| WO2016158708A1 | 2016-10-06 | |||
| WO2000055509A1 | 2000-09-21 |
Attorney, Agent or Firm:
Tetsuo Hirose
Suzuki Yuko
Hirose Ikuo
Suzuki Yuko
Hirose Ikuo