Patent · US Expired

Hydraulic displacement pump having two stroke length

US6267571A · kind A · utility

9Cited by
5References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 17, 1999
Grant dateJul 31, 2001
Priority date
Expiry dateAug 17, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S417/90
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A pump having both a short stroke pumping mode and a long stroke pumping mode. The pump has two material cylinders, each with an attached hydraulic cylinder for operating a piston rod extending through both the material and hydraulic cylinders. The piston rods are driven by hydraulic fluid supplied to the hydraulic cylinders and are synchronized so that as one piston rod extends, the other piston rod retracts. The piston rods draw material into the material cylinders when retracting, and pump material out of the material cylinders when extending. To pump in a short stroke mode, a diverter valve is placed between the hydraulic pump and the hydraulic cylinders which diverts an amount of hydraulic fluid to the cylinders, causing the hydraulic pistons to only be extended about half the length of the hydraulic cylinder.

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