Patent · US Expired

Precompression pump

US5803318A · kind A · utility

33Cited by
3References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 28, 1996
Grant dateSep 8, 1998
Priority date
Expiry dateOct 28, 2016

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB05B11/1025
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A precompression pump has a hollow cylindrical pump body 1 extending axially between a first end 1a and a second end 1c, an annular piston 3 sliding axially in the pump body, the piston and the pump body defining a pump chamber 6, and a push rod 40 for controlling the piston and sliding axially inside it. The push rod includes an outlet channel 41a, 42a which opens out inside the pump body via a lateral opening 42b, and the piston is displaceable relative to the push rod to close the lateral opening or to put it into communication with the pump chamber. A resilient precompression spring 47 urges the piston towards the pump chamber and towards a rest position in which it closes the lateral opening of the outlet channel, and a central section of the piston is isolated from the pump chamber, at least while the piston is in the rest position.

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