US2254907A - Apparatus for making bags and the like - Google Patents

Description

Sept. 2, 1941. A. POTDEVIN ETAL APPARATUS FOR MAKING BAGS AND THE LIKE Filed June 22, 1938 MM ATTo NEYs Patented Sept. 2, 1941 Adolph Potdevin, Garden City, and George E. Hampton, New York, N. Y., assignors to Potdevln Machine Company, Brooklyn, N. Y., a

corporation of New York Application June 22, 1938, Serial to. 215,130

2 Claims. (01. 93-19) This invention relates to an apparatus for the making of bags, being particularly well adapted for making bags of cellulose acetate cellulose hydrate, giassine and the like.

An embodiment of our invention is illustrated in the accompanying drawing, in which:

Fig. 1 is a part sectional elevational view of our improved apparatus; and

Figs. 2 and 3 are more or less explanatory views of the tubed material, as will be brought out hereinafter in detail.

Referring to the drawing in detail: The bag material is taken from any suitable source of supply and tubed about a cut-oil plate, designated 2. The plate 2 is a thin flatplate with up per and lower plane faces and is adapted to be reciprocated lengthwise of the machine and in timed relation with the other mechanism of the machine.

The plate 2 is'adapted to be moved forward or advanced, in the direction of the travel of the bag material which is wrapped or tubed about the plate, by cut-ofi blades or cutters 4 and 6 mounted in cut-oil rollers 8 and I0, respectively.

The plate is retracted by a lever l2 pivoted at M, one end of this lever extending through the tail of the cut-oil plate 2 as shown at IS. The lever I 2 is positively actuated rearwardly by a cam l8 driven by a chain 20, for example, it being understood, of course, that this cam or eccentric l8 1 is driven in timed relation with the rest of the machine so that the plate 2 will be retracted in the proper timed relation to the operation of the cut-ofi blades or knives 4 and 6.

Between the tail end of the plate 2 and the rollers 8 and Ill we provide forwarding rollers 22- and 24 the function of which is to advance the tubed material continuously through the machine to the cut-off rollers 8 and Ill.

The cutters 4 and 6 are set into the face of the rollers 8 and ill, respectively, and held in place therein, for example, by suitable screws 26, a land 28 being set into the face of each'of the rollers 8 and Ill beside the cutters.

The cutters, as will be seen from the drawing,

project slightly from the periphery of the rollers 8 and I0 but it will be appreciated that when the cut-off plate 2 is not being moved forwarder advanced by the cutters and lands the plate is free to be retracted positively by the retracting lever l2, as above explained.

The cut-oil rollers 8 and I0 are so set with respect to each other that the cutter 6, for instance, will perform its cutting operation ahead-of the cutter 4 which, as will be appreciated, will provid a projecting flap on the lower wall of the.

bag material. It is obvious that this order of, operation of the cutters may be reversed. The cut-off rollers are adjustable circumferentially so that the operation of the knives or cutters 4 and 6 may be adjusted to suit varying conditions and may be set with accuracy.

It is to be noted that the cutters 4 and 6 are not serrated but are smooth edged.

The plate 2 is of such length that when it. is in its retracted position it is picked up and advanced by the land 28 lying beside the cutter 4, so that as the cutter 6 engages the lower wall of the tubed material-30 it will roll overthe plane face of the hard metal cut-off plate 2 to cut through the lower wall of the tubed material with a smooth rolling pinch cut. This cut is shown in Fig. 2 and designated 32. As will be seen from the drawing, the cut extends transversely of the tubing or to a point adjacent the opposite edge, and inasmuch as the land 28 lying beside the cutter4 isbearingagainst the upper side of the plate the latter will be carried forward or advanced at cutter speed during the cutting operation. The operation just described is followed by a similar operation as the cutter 4 rolls over the upper face of the plane face of'the cut-off plate 2 partially to divide the upper wall of the tubed material with a rolling pinch cut as shown at 34in Fig. 2, the land 28 in the lower roller I0 engaging the lower face of the plate and moving the same forward at cutter speed.

These are partial severing or dividing operations and during these operations the bag tubing is in engagement with the rollers 88 which are just beyond the cutter rollers 8. and I0 and which keep the tubing from plugging.

Inasmuch as the cutters 4 and 8 engage only the plane faces of the cut-off plate 2 it will be appreciated, of course, that the edges of the tubed material for a distance at least equal to the thickness of the cut-ofl' plate are still uncut.

v the same in the direction of the length of the tubed material to finish -the dividing operation thereof, as shown at 42 and 44. This dividing operation is followed by cutting out or trimming the corners of the trailing end of each bag length.

In this connection, the rollers 38 are equipped with cams 46 for controlling cutter or punch operating levers 48, each pivoted at 50. Lying below the advancing bag length is a die plate 52, and springs 54 having one end secured to this die plate and their other ends to the free ends of the levers 48, as seen in Fig. 1. Attached to the levers 48 are die plungers 56 cooperating with the die plate 52 to cut out or trim the corners of the trailing end of each bag length, as shown at 58 in Fig. 2. The die plungers 56 are so shaped that the bottom 60 of each of the cut-outs 58, with the tubed material flat, as illustrated in Fig. 2, will be below the outer edge of each cut-out, that is, below the edge of the tube. The result of this type of a cut or trim is that when the tubed material is opened up, as illustrated in Fig. 3, the bottom of each notch is in the form of an inverted V, designated 62, and if tension is placed on the tube in the direction of the arrows on Fig. 3 tending to tear the tube at the comers, the tension is transferred from the edge of the end of the tube to below the apex Q2 of the inverted Vs 62, practically necessitating bursting of the material of the tube below the apex of each V before a tear can start.

It will be seen from all of the foregoing that we have provided a mechanism or apparatus adapted for use in the making of bags and the like wherein the bag material is tubed, partially divided into bag lengths by a rolling pinch cut, the dividing operation being completed by placing the tubed material under longitudinal tension, the comers of the trailing end of each bag length finally being trimmed. This end of the bag length is the open end of the finished bag 1. A bag making machine, comprising in combination tubing mechanism, means for continuously advancing the tubing, cutter carrying rollers in the path of the advancing tubing, for partially dividing thetubing into bag lengths, forwarding rollers adapted to engage the tube during said dividing operation, a second pair of rollers traveling at a higher peripheral speed than said forwarding rollers, the said second pair of rollers engaging the partially divided tubing to exert a pull on the tubing in the direction of its length to complete the dividing operation, and cutters adapted thereafter to cut back the opposed corners of the trailing end of the bag length to provide cut-backs at opposite edges of the tubing, said cut-backs being so shaped that the bottom of each of said cut-backs forms an inverted V when the bag length is opened.

2. A bag making machine, comprising in combination a smooth faced cut-off and tube forming plate, tube forming mechanism adapted to tube the bag material about said forming plate, said plate being mounted on the tube forming mechanism and the cutting end having reciprocating motion relatively thereto, forwarding means for advancing the tubing along said plate, a pair of rollers in the path of the tubing, a cutter carried by each roller, said cutters engaging the walls of said tubing at bag length intervals and rolling upon the smooth surfaces of said cut-off plate to cut through the upper and lower walls of the tubing transversely thereof with a pinch out, partially to divide the tubing into bag lengths, said plate being moved forward by the rollers and cutters during such operation, a cam actuated lever for returning said plate to its initial position after each cutting operation, rollers adapted to engage the partially divided tubing after the operation of the first mentioned cutters to complete the dividing operation, and cutters adapted thereafter to-cut back the opposed corners of the trailing end of the bag length to provide cut-backs at opposite edges of the tubing, said cut-backs being so shaped that the bottom of each of said cutbacks forms an inverted V when the bag length is opened.

ADOLPH POTDEVIN. GEORGE E. HAMPTON.

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