Patent · US Expired

Hydraulic pressure control circuit for a working machine

US6269637A · kind A · utility

3Cited by
1References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 7, 1999
Grant dateAug 7, 2001
Priority date
Expiry dateJul 7, 2019

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE02F9/2285
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

When a working implement comes close to a cab during operation, for efficiency, the operation should continue insofar as possible yet it is essential the working implement be prevented from striking the cab. To that end, a pilot pump oil line capable of supplying pilot pressurized oil to a solenoid proportional pressure reducing valve in a state where a control member is not manipulated, is provided in a stick contraction-side pilot oil line. When the working implement enters an interference prevention area, defined around the cab, the stick is automatically moved out so that the operation can continue yet the working element avoids the interference prevention area.

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