The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 31, 1992
Filed:
Jun. 04, 1990
Jose E Valls, Jr, Ponce, PR (US);
Vassallo Research and Development Corporation, Coto Laurel, PR (US);
Abstract
Plastic pipe has a cylindrical body having longitudinally extending concentric walls spaced from the longitudinal axis of the pipe. The walls are connected by ribs extending generally radially between the walls and longitudinally of the pipe. The pipe is provided with a generally annular resilient axially extending sealing ring entrapped at the end of the pipe by removing an end portion of the ribs, heating and bending an end wall portion so as to entrap a portion of the sealing ring, while permitting a second portion of the ring to axially project beyond the end of the pipe to provide impact resistance to the pipe end. A further embodiment involves omission of the sealing ring and welding the small gap remaining after heating and bending an end wall portion to seal the pipe end.