Patent · US Expired

Plastic pipe with locking integral end connection

US4875714A · kind A · utility

58Cited by
21References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 28, 1988
Grant dateOct 24, 1989
Priority date
Expiry dateSep 28, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/5367
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

Plastic, such as polyolefin, pipe having a locking integral end connection. The pipe is fabricated with male and female end connections in order that the pipe may be press-fitted together with the interior and exterior forming a flush uninterrupted surface. One or more radial ribs and grooves are formed on the interior of the female connection while a registering series of ribs and grooves are formed on the exterior of the male connection. The ribs and grooves are of an interfitting axially extending wedge shaped configuration to provide a locking engagement to resist any tendency for separation. Interfitting corners of the ribs and grooves may be rounded to distribute stress and minimize damage when the pipe ends are fitted together. The ends of the pipe are bevelled in order that the ends pressed together engage and by the slight resiliency of the polyolefin pipe construction permit the slight expansion and contraction of the ends to provide a locking interfit of the respective ribs and grooves in the two ends. A reinforcing sleeve may be used over the coupling for additional strength. The wall thicknesses of the end connection and width of the ribs and grooves are particularly d…

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