Apparatus and method for forming handles in plastic bags

A method of forming plastic bags, comprising the steps of:

• providing a collapsed tube of thermoplastic film traveling in a longitudinal direction;
• forming pairs of closely-spaced, parallel transverse heat seals at bag-length distances apart;
• forming transverse lines of weakness between each of said pairs of transverse heat seals such that said collapsed tube includes a plurality of handleless bags interconnected along said transverse lines of weakness;
• and
• passing each of said handleless plastic bags between a rotary anvil and a rotary cutting die to form a pair of handles in each of said bags, said rotary anvil having a first axis of rotation, said rotary cutting die disposed adjacent to said rotary anvil and having a second axis of rotation substantially parallel to said first axis of rotation, said rotary cutting die including a rotatable cylindrical shaft, a blade shell mounted on said shaft, and a generally W-shaped blade formed on said blade shell, said blade having a base portion and a pair of substantially linear opposing legs, said base portion having an inverted, V-shaped configuration, said opposing legs extending upwardly relative to said base portion and outwardly relative to each other, said opposing legs being coupled to said base portion via transition portions, said blade creating a generally W-shaped incision in each of said handleless bags.

A method of forming plastic bags, comprising the steps of:

• providing a collapsed tube of thermoplastic film traveling in a longitudinal direction;
• forming pairs of closely-spaced, parallel transverse heat seals at bag-length distances apart;
• forming transverse lines of weakness between each of said pairs of transverse heat seals such that said collapsed tube includes a plurality of handleless bags interconnected along said transverse lines of weakness;
• and
• passing each of said handleless plastic bags between a rotary anvil and a rotary cutting die to form a pair of handles in each of said bags, said rotary anvil having a first axis of rotation, said rotary cutting die disposed adjacent to said rotary anvil and having a second axis of rotation substantially parallel to said first axis of rotation, said rotary cutting die including a rotatable cylindrical shaft and a generally W-shaped blade mounted to said shaft, said blade having a base portion and a pair of substantially linear opposing legs, said base portion having an inverted, V-shaped configuration, said opposing legs extending upwardly relative to said base portion and outwardly relative to each other, said opposing legs being coupled to said base portion via transition portions, said blade creating a generally W-shaped incision in each of said handleless bags.