Patent · US Expired

Regenerative and anticavitation hydraulic system for an excavator

US4359931A · kind A · utility

19Cited by
13References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 19, 1981
Grant dateNov 23, 1982
Priority date
Expiry dateJan 19, 2001

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF15B2211/865
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydraulic system (40) for an excavator (10) which utilizes regeneration, minimizes cavitation, and provides hose break protection is disclosed. A valve assembly (50) is permanently connected to a hydraulic actuator (30) which is to be controlled. A hydraulic power supply (42) remote from the hydraulic actuator is connected to the valve assembly (50) through a pair of flexible hoses (56, 58). Pressurized hydraulic fluid can flow to the valve assembly through either of the flexible hydraulic hoses, but the valve assembly (50) includes a check valve (60) so hydraulic fluid return is only possible through one hose (56). A two position valve (62) is provided in the valve assembly (50) between a pair of operating ports (36, 38) on the hydraulic actuator (30). The two position valve (62) can be opened in response to a signal from the operator, connecting the two ports (36, 38) together to permit regeneration. The valve assembly (50) also includes a pressure relief valve (64) connected to one of the ports (38) to limit overpressure. A second check valve (66) is connected around the pressure relief valve (64) to permit hydraulic fluid to flow from a reservoir (43) to the hydraulic actuato…

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