Patent ID: 6519918
Filing Date: 2003-02-18
Classification: B29C,B29D,B31B,B65B,B65D,Y10S

Abstract:
A method of making a resealable package having front and back faces and a reclosable interlocking seal having a female outer part and a male inner part, comprising the steps of,a) transporting in lengthwise direction a web of flexible packaging material of selected width and indeterminate length having thermoformable strips of a length substantially greater than the strip width affixed to the web with the strip length oriented transversely to the running length of the film at package length intervals, b) passing said film over a forming collar and around a cylindrical forming tube and forming a longitudinally sealed cylindrical tube of packaging film with the thermoformable strip inside the film tube in substantially ends-abutting relationship, and with the surface of the strip not secured to the film in facing relationship within the tube, c) moving the portion of the tube within which the strip is disposed between a pair of spaced apart heated male and female forming dies, d) moving said dies toward one another to press the face of the strip not secured to the film against itself to form two apposed strip faces extending entirely across the film tube, and continuing to move said dies toward one another into mating position and forming the central part of the strip extending across the film tube into a recess of said female die to form a tip of an arrowhead shape of the reclosable seal, e) moving toward one another into closed position a pair of interlock forming heated dies positioned at opposite sides of the female die to press portions of the margins of the strip immediately adjacent to the central part of the strip inward against one another to complete the inner male and outer female parts of the reclosable interlocking seal held between the female die and the pair of interlock forming heated dies while partially retracting the male die, and f) fully retracting the male and female dies to their initial positions.