초록 ▼

A vertical form, fill and seal packing machine and method for making recloseable bags having a safety seal exterior to a recloseable seal. The machine produces durable, substantially air-tight bags at high speed and provides for the production of different size and make of bags and different amounts

A vertical form, fill and seal packing machine and method for making recloseable bags having a safety seal exterior to a recloseable seal. The machine produces durable, substantially air-tight bags at high speed and provides for the production of different size and make of bags and different amounts and types of product in the bags. The machine includes a film drive and pinch roll pair, a pair of film pull belts, and a pair of zipper drive rollers for pulling the plastic film and zipper strip through the machine. The production of different size bags is facilitated by having the film drive roll, pull belts, and zipper drive rollers simultaneously driven in bag length increments by a common drive source. Also, to accommodate the production of different size bags, the machine includes a programmable control system, an optical mark sensor, and an adjustable film path length. Further, the machine and method of the present invention ensures reliable seals along the edges of each product-filled bag by having the zipper drive rollers and a bag grabber mechanism stretch the bag material prior to squeezing the excess air out of the product-filled tube and then cross-sealing and severing the bag material. The machine includes a bag squeezer unit having opposing squeeze plates or pads for removing excess air and/or compacting the product to form a reduced size, recloseable bag.

대표청구항 ▼

[ What is claimed as invention is:] [18.] In a method of forming separate, product-filled, reclosable bags from a heat sealable plastic film and zipper which form a plastic tube, the improvement comprising:horizontally elongating the plastic tube transverse to its length prior to severing and format

[ What is claimed as invention is:] [18.] In a method of forming separate, product-filled, reclosable bags from a heat sealable plastic film and zipper which form a plastic tube, the improvement comprising:horizontally elongating the plastic tube transverse to its length prior to severing and formation of seals using tensioning means, andsqueezing the excess air from each product-filled bag prior to final formation thereof using a pair of opposing, rigid, planar squeeze plates mounted to a rotary actuator assembly and having flat inner surfaces which are brought into contact with the sides of the bag to remove excess air therefrom and at least partially compact the product therein.