Abstract The bag machine of the present disclosure is of the type which can produce bags made of various thermoplastic sheet material and can be adapted to make side weld or bottom weld bags. The following description will, however, be confined to the production of side weld bags. A roll of plastic web is mounted on an unwind stand and traverses a folding board constraining the web to fold along its longitudinal median or along a line spaced from and parallel to the longitudinal median in the event it is desired to produce wicketed bags having a lip with a pair of holes in which is inserted a U-shape wire called a wicket. Downstream of the folding board a gusseter is provided to produce a fold which permits greater expansion at the bottom of the bag. The folded and gusseted web thence comes under the influence of a reciprocating transversely disposed seal and cutter bar which divides the web, at longitudinally spaced intervals, to produce individual bags. The bags are then transported to a table which is provided with devices for arranging the bags into a stack.
An apparatus for making thin thermoplastic bags from an elongate folded web comprising means for supplying such web folded along a line intermediate its edges, means for accumulating a quantity of the folded web and for imposing a desired tension to the web, means for intermittently pulling the web from said accumulating means while causing the web to be withdrawn from said supply means at substantially a constant rate, means located between said web supply means and said accumulating means, for forming a gusset at the folded margin of the web.
Claim 2
Independent Claim
91 words
An apparatus for making thin thermoplastic bags from an elongate folded web comprising means for supplying such web folded along a line intermediate its edges, means for accumulating a quantity of the folded web and for imposing a desired tension to the web, means for intermittently pulling the web from said accumulating means while causing the web to be withdrawn from said supply means at substantially a constant rate, means located between said web supply means and said accumulating means, for forming a gusset at the folded margin of the web.
Claim 3
Dependent Claim
31 words
The apparatus of claim 1 wherein said gusset forming means comprises cooperating gusset forming members mounted on a frame which is movable relative to the longitudinal median of bag making apparatus.
Claim 4
Dependent Claim
29 words
The apparatus according to claim 1 wherein said gusset forming means includes vertically spaced rigidly mounted stationary plates having located therebetween a rotatable wheel resilieNtly biased between said plates.
Claim 5
Dependent Claim
40 words
The apparatus according to claim 3 wherein said plates are provided with at least one set of additional mounting holes so that they may be repositioned on the support therefor to present unworn plate margins to engage the moving web.
Claim 6
Dependent Claim
45 words
The apparatus according to claim 3 further comprising means mounting said rotatable wheel for pivotal movement toward and away from said plates, and means for holding said wheel away from said plates to facilitate threading of a new roll web through said gusset forming means.
Claim 7
Dependent Claim
41 words
The apparatus according to claim 5 wherein said wheel mounting means is connected to a spring which is arranged to impart a selected preload to said wheel dictated by the depth of the gusset desired and the machinability of the web.