The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Apr. 26, 2022

Filed:

Sep. 27, 2019
Applicant:

Doosan Infracore Co., Ltd., Incheon, KR;

Inventor:

Hyeonsik Ahn, Seoul, KR;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F15B 11/05 (2006.01); E02F 9/22 (2006.01); F15B 13/02 (2006.01);
U.S. Cl.
CPC ...
E02F 9/2225 (2013.01); E02F 9/2267 (2013.01); F15B 11/05 (2013.01); F15B 13/026 (2013.01); F15B 2211/40569 (2013.01);
Abstract

A control system for construction machinery includes a hydraulic cylinder operable by a working oil discharged from a hydraulic pump, a control valve arranged between the hydraulic pump and the hydraulic cylinder to control an operation of the hydraulic cylinder according to a position of a spool therein, the control valve having a first spool position for draining the working oil discharged from a chamber of the hydraulic cylinder to a drain tank, and a pressure compensated valve installed in a return hydraulic line through which the working oil discharged from the control valve at the first spool position is drained to the drain tank, the pressure compensated valve being configured to control a flow rate of the working oil passing through the pressure compensated valve according to a pressure difference between a front end and a rear end of the control valve.


Find Patent Forward Citations

Loading…