Patent ID: 6254521
Filing Date: 2001-07-03
Classification: B29C,B29L,B31B,B31F,B65D

Abstract:
A bag making machine for producing stacks of folded flat plastic bags from a tubular gusseted web having a gusset in each side and each bag having a closed bottom end extended across said gusset web and having an inwardly opening V-shaped hinge pattern of creases within each said gusset with the bottom leg of the hinge pattern extending from the bottom end of the bag to the outer gusseted edge of the bag and the upper leg of the crease pattern extending from the bottom leg and outer gusseted edge of the bag to the inner gusset edge, said pattern unfolding the bottom portion of the bag including said hinge pattern and establishing a flat bottom wall upon opening of the folded flat plastic bag, comprising:a first section including means to form the gusseted flat tubular web into a series of segments each having a length equal to two bags, and comprising a creaser unit to form a W-crease pattern in said gussets of said web at an end seal line extended across said tubular gusseted web and between said adjacent bag segments to form said V-shaped crease pattern adjacent the opposite sides of said seal line, a slit/seal unit configured and operable to form a transverse thin end seal in said web at said end seal line and to sever the center of said seal to form adjacent bottom end seals of adjacent bag segments, and a stacking support configured and operable to receive and assemble said bag segments into a segment stack,a second section located to receive said segment stack and including a separation die on a severing unit aligned with the center of the segment stack and configured for severing a slug portion of said segment stack at the center portion of said segment stack to form bag stacks to the opposite sides of said segment stack and with said slug portion between said bag stacks and defining the open end of the bags in said bag stack, said separation slug portion being formed with a plurality of small interconnections to the adjacent bag stacks and interconnecting the bags in each bag stack to each other at said open ends, a separation unit including clamp units and a slug removal unit, a powered unit connected to said clamp units and a powered unit connected to said slug removal unit and configured to sequentially operate said clamp units and said slug removal unit to form the open ends of the bags in said bag stack without separation of the individual bags in each stack from each other, anda conveyor unit configured to grasp the downstream end of said segment stack at said stacking support and move and hold said segment stack within said severing unit and said separation unit, said conveyor unit configured to move the downstream bag stack from said separation unit and to return and grasp the upstream bag stack and move the upstream bag stack from said separation unit and then return to grasp another segment stack at said stacking support.