Patent · US Expired

Heat control system for packaging machine

US4454704A · kind A · utility

14Cited by
10References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 18, 1981
Grant dateJun 19, 1984
Priority date
Expiry dateNov 18, 2001

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB65B2051/105
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A heat control system used in apparatus for packaging articles in a tray by applying a film of thermoplastic material over the articles in the tray. The apparatus includes a plurality of electrically operated heating units successively moving along a prescribed path and adapted to captivate each tray and the film over the articles in the tray between adjacent heating units as the heating units move along a prescribed portion of the prescribed path to press the film against opposite sides of the tray and heat the film to a temperature to cause the film to bond to the tray. The heat control system includes temperature control means for controlling the temperature of each of the heating units, detection means for detecting when each of the heating units is in position to press the film against the tray, and timing means connecting the temperature control means and the detection means so that the timing means is activated while the detection means detects that the heating unit is in position to press the film against the tray to cause the temperature control means to lower the temperature of the heating unit from a prescribed higher welding temperature sufficient to bond the film to th…

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