Patent · US Expired

Piston, method of making the piston and piston and cylinder unit comprising the piston

US5174192A · kind A · utility

0Cited by
4References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 15, 1991
Grant dateDec 29, 1992
Priority date
Expiry dateOct 15, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49256
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A piston for a door closer comprises metal cups on opposite ends of a stem. A plastics ring is a snap-fit in one of the cups and protrudes from that cup to seal against the wall of a cylinder. A groove in the side wall of the cup for receiving a rib on the ring is formed by pressing a substantially flat blank before the blank is formed into the cup.

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