Patent · US Expired

Method and apparatus for manufacturing foldable conduit

US4527319A · kind A · utility

24Cited by
25References
57Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 28, 1981
Grant dateJul 9, 1985
Priority date
Expiry dateSep 28, 2001

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T156/1741
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A sleeve of plastic material from an extruder is molded by a blow molding apparatus into a tubular structure which includes two top walls longitudinally connected at base ends and apex ends. A splitting apparatus splits the longitudinally connected base ends apart to form two top walls. The top walls are oriented with their base ends upward. An extruder extrudes a flow of softened plastic which is divided by a manifold into four flows. Four applicators connected with the manifold apply beads of softened plastic along each top wall base end. A ribbed roller presses flexible strips against the plastic beads on each of the top walls. The flexible strips are fed from rolls of finite length mounted on a stand. The stand holds operating rolls and back up rolls. A splicing apparatus splices the trailing end of each operating roll with a leading end of the corresponding back up roll. An accumulator accumulates a reserve of the flexible strip between splices and feeds out the reserve during a splice such that the flexible strip is fed continuously to the ribbed roller. A perforator apparatus perforates the flexible strip and a vent trimmer perforates the top wall. A puller clamps the condui…

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