Patent · US Expired

Heating device for sealing material to effect different bond strengths

US4735675A · kind A · utility

19Cited by
11References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 26, 1982
Grant dateApr 5, 1988
Priority date
Expiry dateApr 26, 2002

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C66/919
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The present invention is used to heat seal seams, and the like, of item holding means such as plastic bags holding loose fill product like beans, hard candy, pretzels, potato chips, etc. The heating station of the present invention has at least two independently controlled heating positions in each half of a pair of jaws and each heating position is heat insulated from the other and each respectively can provide different amounts of heat to material coming in contact therewith. Accordingly, the bonded areas of item holding means can be manipulated to control local package characteristics, i.e., sealed to have a stronger bond strength at one location that at another location, adjust tear properties to suit marketing methods (such as hole punched top seals) and to control seal integrity.

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