Patent · US Active

Hydraulic circuit for construction machine and control device for same

US9725884B2 · kind B2 · utility

7Cited by
2References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 28, 2014
Grant dateAug 8, 2017
Priority date
Expiry dateSep 18, 2035

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF15B2211/7142
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A hydraulic circuit of a construction machine including center bypass passages, into which a pressurized oil from hydraulic pumps is supplied, includes a directional control valve group in tandem with the center bypass passages; a bleed-off valve on a downstream side of each center bypass passage; and a merging circuit that merges the pressurized oil supplied into one center bypass passage and that in another center bypass passage, wherein each directional control valve includes a first internal passage that flows the pressurized oil into the center bypass passages, and a second internal passage that supplies the pressurized oil to a hydraulic actuator, wherein the center bypass passages and the first internal passage form a parallel passage, wherein an opening area of the bleed-off valve is changed, wherein the merging circuit includes a merging directional control valve that controls an inflow direction of the pressurized oil to be merged.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.