Patent · US Expired

Hydraulic pump assemblies

US4778350A · kind A · utility

1Cited by
8References
6Claims
0Family size

Assignees

Inventors

Key dates

Filing dateFeb 27, 1987
Grant dateOct 18, 1988
Priority date
Expiry dateFeb 27, 2007

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF04B23/02
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A hydraulic pump assembly includes a cam shaft, a pair of high pressure plunger pumps opposed to each other on a first common axis, each of the high pressure plunger pumps having a first plunger of small diameter perpendicular to the cam shaft for reciprocation by engagement therewith, a low pressure plunger pump arranged on a second axis angularly displaced with respect to the first common axis in a circumferential direction of the cam shaft, the low pressure plunger pump having a second plunger of large diameter perpendicular to the cam shaft for reciprocation by engagement therewith, an accumulator arranged to temporarily store hydraulic fluid under pressure discharged from the low pressure plunger pump, and a relief valve arranged to release an excessive hydraulic pressure from the accumulator for maintaining the hydraulic pressure in the accumulator in a predetermined value. The high pressure plunger pumps are arranged to be supplied with the hydraulic fluid under pressure from the accumulator.

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