Patent · US Expired

Stretcher for package forming

US4869048A · kind A · utility

55Cited by
7References
25Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 5, 1988
Grant dateSep 26, 1989
Priority date
Expiry dateAug 5, 2008

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C66/8242
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A method and apparatus for forming bags such as in a form, fill and seal machine wherein the bags are formed by drawing film downwardly over a filling tube and cross-sealing the bag tube and applying a lateral stretching force to the bag tube at the location of cross-sealing preventing wrinkles at the location of the seam formed by the cross-sealing with the stretching force applied at the extreme lateral edge of the film preferably by opposed cam surfaces at each of the bag edge which contact each other at a point just outside of the bag edges and progressively walk into the edge of the bag with the point of contact shifting in an outward direction while it progresses inwardly on the bag to apply a stretching force to the film of the bag for smoothing the entire width.

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