US3002431A - Machine for forming folded top and bottom ends of a bag - Google Patents

Description

Oct. 3, 1961 M. RAWE 3,002,431

MACHINE FOR FORMING FOLDED TOP AND BOTTOM ENDS OF A BAG Filed Dec. 12, 1957 5 Sheets-Sheet l i i-L IN V EN TOR.

M. RAWE Oct. 3, 1961 MACHINE FOR FORMING FOLDED TOP AND BOTTOM ENDS OF A BAG Filed Dec. 12, 1957 5 Sheets-Sheet 2 i lql INVENTOR.

M. RAWE 3,002,431

MACHINE FOR FORMING FOLDED TOP AND BOTTOM ENDS OF A BAG Oct. 3, 1961 5 Sheets-Sheet 5 Filed Dec. 12, 1957 MMQ INVENTOR.

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MACHINE FOR FORMING FOLDED TOP AND BOTTOM ENDS OF A BAG Filed Dec. 12, 1957 M. RAWE Oct. 3, 1961 5 Sheets-Sheet 4 IN V EN TOR.

By m M- Oct. 3, 1961 RAWE 3,002,431

MACHINE FOR FORMING FOLDED TOP AND BOTTOM ENDS OF A BAG Filed D80. 12, 1957 5 Sheets-Sheet 5 i 'gi 3,602,431 MACEHNE FOR FQRMING FOLDED TUE AND BQTTOM ENDS OF A BAG Martin Rowe, Tecklenburg, Westphalia, Germany Filed Dec. 12, 1957, Ser. No. 702,482 Qlaims priority, application Germany Dec. 13, 1956 6 Claims. (Cl. 93-48) The present invention relates to machines for manufactoring bags. In particular, the present invention relates to machines for forming folded top and bottom ends of a bag.

In conventional machines of this type the ends of a hat tubular bag-forming blank are folded into partially complete bag ends which are respectively located in vertical planes while the remainder of the blank remains in a horizontal plane. With such machines it is necessary to turn the partially complete bag ends through 90 into a horizontal plane'in order to be able to apply glue thereto, and this requirement of turning the bag ends through 90 raises great problems in actual practice because of the relative stiffness of the sheet material of the bag.

In order to overcome this problem it has already been proposed to deflect the end portions of the flat tubular blank into a pair of vertical planes while the remainder of the blank remains in a horizontal plane, and then these end portions are folded into the partially complete bag ends while the end portions are in these vertical planes. However, this type of construction is not suitable for the manufacture of bags of relatively short lengths because the folding devices and the like which act on the end portions of the blank require a considerable amount of volume, and because of the space which is taken up by these mechanisms they cannot be located beside each other at a distance short enough to provide bags of relatively short lengths. While it might be possible to arrange such folding devices one behind the other' in partly overlapping relationship along the path which is provided for the blank, such an arrangement is not practical because this would necessitate folding of the end portions of the blank separately with the folding of one end portion taking place after the folding of the other end portion. Because only one end portion would be folded at a time the blank would necessarily become distorted and would create great difficulties in the manufacture of a good bag. Moreover, with such an arrangement of the folding mechanisms the size of the machine would be undesirably large.

One of the objects of the present invention is to overcome the above drawbacks by providing a machine which is capable of manufacturing a relatively short bag while at the same time simultaneously folding both ends of the blank and also While requiring the partially complete bag ends to be turned through only an extremely small angle into a horizontal position to receive glue, so that no particular difficulties arise because of the relatively stiil sheet material used for the bag.

Another object of the present invention is to provide a bag-forming machine which is capable of having its various components located close to each other in a relatively small space.

A further object of the present invention is to provide a machine of the above type with means for applying Patented ct, 3, 1961 glue to the ends of a relatively short blank which is to be formed into a relatively short bag.

With the above objects in view, the present invention includes in a machine for forming folded bag ends, a support means and a transporting means carried by the support means for transporting a flat tubular bag-forming blank along a predetermined path in a predetermined plane with the blank located in this plane. in accordance with the present invention, the end portions of the blank are deflected, While the blank is being transported along the predetermined path, through less than into a pair of oppositely inclined planes which make angles of less than 96 with the predetermined plane along which the blank is transported by the transporting means. A pair of folding means are carried by the support means, in accordance with the present invention, for simultaneously folding the deflected end portions of the blank while these end portions are still in the pair of oppositely inclined planes, the pair of folding means folding the end portions into partially complete bag ends. Thereafter the structure of the invention applies glue first to one of the partially complete bag ends and then to the other of the partially complete bag ends wi h a pair of glueepplying means which are arranged one behind the other along the path of movement of the blank in partly overlapping relationship, so that the pair of glue-applying means are capable of applying glue. to a relatively short bag length even though the structure for applying the glue requires such a space that the pair of glue-applying means could not be located beside each other and still apply glue to the relatively short bag lengths.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional obiects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

E6. 1 is a partly schematic side elevation view of a machine according to the present invention;

FIG. la is a fragmentary perspective view of a blank in a position in which one of its end portions is engaged by a deflecting and guiding rail;

FIG. 2 is a transverse sectional view taken along line Ill-11 of PEG. 1 in the direction of'the arrows and showing part of the transporting means as well as structure for forming folding grooves in the blank;

FIG. 3 is a fragmentary transverse sectional View taken along line ill-4H of FIG. 1 in the direction of the arrows and showing the structure for opening the end portions of the tubular fiat bag-forming blank;

FIG. 4 is a transverse sectional view taken along line lV-IV of FIG. 1 in the direction of the arrows, FIG. 4

showing the structure for folding the ends of the blankinto partially complete bag ends;

PEG. 4a is a plan view of the structure shown at the upper right hand side of FIG. 4, as seen in the direction of the arrow at the upper right part of FIG. 4;

PEG. 5 is a fragmentary sectional transverse view taken along line V-V of FIG. 1 in the direction of the arrows and showing one of the glue-applying means of the present invention;

16. 6 is a fragmentary transverse sectional view taken along line VI-Vi of FIG. 1 in the direction of the rows and showing the other of the glue-applying means of the present invention; and

FIG. 7 is a fragmentary transverse sectional view taken along line Vll Jli of FIG. 1 and showing the structure for providing grooves in the partialiy complete bag ends so that these grooves will form fold lines along which the flaps of the bag ends may be folded to form the complete ends of the bag.

Referring to FIG. 1 in which the entire machine is schematically illustrated, it will be seen that the machine includes a support means made up of a machine frame 3 which is carried by a base piate 2;. The frame 1 carries a transporting means which is made up in part by a pair of transporting rolls and 5' shown at the left of FIG. 1, and this transporting means transports the fiat tubular bag-forming blank 4 along the predetermined path which is a straight line extending from the left to the right of FIG. 1 in a predetermined horizontal working plane 3 indicated in PEG. 1. The blank 4 is arranged with its axis extending across the path of movement of the blank so that the opposite open ends of the blank are arranged at opposite side of the path along which the blank is transported by the transporting means. The transporting means first transports the blank to a device 6, the details of which are shown in FIG. 2, for providing scoring grooves in the blank so that these grooves provide fold lines along which the blank is folded. After passing through the scoring means 6 the blank is engaged by an additional set of transporting rolls 7 of the transporting means and is advanced to the right, as viewed in FIG. 1, along a deflecting means which includes deflecting and guiding rails 8 which deflect the end portions of the blank which extend beyond the scoring lines simultaneously through less than 90 into a pair of oppositely inclined planes which make less than 90 with the horizontal working plane 3 (see PEG. la), and this angle through which the end portions of the blank are deflected is indicated at alpha in FIG. 4.

With the end portions of the blank deflected into the pair of oppositely inclined planes the blank is transported by the transporting means toa means shown in FIG. 3 for opening the ends of the blank. This opening means takes the form of a suction and spreading device 9. After leaving the opening means 9 shown in FIG. 3 the blank with its ends still deflected into the pair of oppositely inclined planes, respectively, reaches the pair of folding means shown in FIG. 4 which simultaneously fold the deflected bag ends into partially complete bag ends. The arrangement of the end opening means 9 and folding means it along the path of movement of the blank is indicated in FIG. 1. FIGS. 4 and 411 show the details of the folding means, and these details are described below. The blank leaves the pair of folding means 10 with both ends of the blank folded into planes which are respectively perpendicular to the oppositely inclined planes into which the end portions of the bag blank were deflected, and then a further deflecting means carried by the support means 1, 2 deflect the partially complete bag ends through relatively small angles into horizontal planes where the partially complete bag ends are adapted to receive applications of glue. At this time the blank is transported by the transporting rolls 11 indicated in FIG. 1, these rolls 11 also forming part of the transporting means of the structure of the invention. The transporting rolls 11 deliver the blank to tong-like gripping devices 12 carried by moving endless chains 13, and these gripping devices deliver the blank 4 to a pair of giue-applying means shown in FIGS. 5 and 6, respectively, the blank being first d livefed to -applying means 14 shown in FIG. 5 and then m the lue-applying means 15 shown in FIG. 6. The pair of glue-applying means apply glue first to one and then to the other of the partially complete bag ends, and after passing through the pair of glue-applying means the blank is moved through an additional scoring means 16, the details of which are shown in FIG. 7, and this latter scoring means provides a pair of scoring grooves in each partially complete bag end so that the partially complete bag end may then be folded in a known and conventional manner into the finished bag end.

The drive of the machine is taken from an electric motor 17 which drives a belt 18 which cooperates with a flywheel 19 so as to rotate the latter (FIG. 1). Through a suitable gear drive 24 which is driven by the flywheel 19, the drive is transmitted to a pair of drive shafts 21 which extend along the entire length of the machine. From these drive shafts 21 suitable bevel gear drives 22 transmit the drive to chains 23 which actuate the transporting rolls 5 and the scoring device 6. In the same way the drive for the transporting rolls 7 is derived from bevel gears 24 and chains 25 which cooperate with the drive shafts 21. The suction and spreading means 9 which opens the bag ends derives its drive from the bevel gears '26 which are driven from the shaft 21, while the pair of folding means 10 are driven by bevel gears 27 which cooperate with the drive shaft 21. A pair of auxiliary drive shafts 23 and sets of bevel gears 29 and 29' serve to deliver the drive from the shafts 21 to the endless chains 13. The glue-applying means 14 and 15 as well as the final scoring means 16 derive their drive from the bevel gears 30, 3% which also cooperate with the main drive shafts 21.

According to the present invention the suction and spreading means 9 shown in FIG. 3 and the pair of folding means 19 shown in FIGS. 4 and 4a are inclined with respect to the horizontal working plane 3 so that the end portions of the tubular flat blank are worked on while they are neither in a vertical nor in a horizontal plane, but rather while they are in a pair of oppositely inclined planes which make relatively sharp angles of less than 99 with the horizontal plane of the remainder of the blank. In this way it is possible to arrange the pair of end opening means 9 as Well as the pair of folding means Cid so close to each other along the central longitudinal axis of the machine that it is possible to work on extremely short bag lengths while simultaneously forming both ends of the bag. If the end portions of the blank were folded into the horizontal plane 3, then the spreading and folding devices could not be located close enough to each other in order to manufacture short bags. On the other hand, with the relatively stiff sheet material of the bags, great difficulties would arise if, in order to arrange the end opening and folding devices close to each other the ends of the blank were folded into a vertical plane. In this latter case the partially complete folded bag ends would have to be turned through a full into the horizontal plane in order to be able to receive glue at the glueing stations 14 and 15'. Such a turning of the partially complete bag ends through 90 results in stresses and the formation of creases which are very undesirable, when the material of the blank is relatively stiff, as is conventional.

Furthermore, in accordance with the present invention, the pair of glue-applying means 14 and 15 are arranged one behind the other in partly overlapping relationship, so that glue may be applied to both of the end portions of the bag one after the other. With such an arrangement the pair of glue-applying means are also capable of operating with blanks of extremely short lengths without in any way interfering with each other, as would be the case if the pair of glue-applying means were arranged directly beside each other.

The scoring means 6 which is illustrated in FIG. 2 provides during transportation of the blank a pair of score lines thereon adjacent and parallel to the ends of the blank so that the end portions of the blank may be deflected downwardly at these score lines. The structure at the left side of FIG. 2 for providing one of the score lines and for simultaneously transporting the blank is identical with the structure shown at the right side of drive 42, 42 in the manner indicated in FIG. 3.

FIG. 2, this structure at the right side being a mirror image of the structure at the left side, so that only the structure at the left side of FIG. 2 will be described. Both of these structures are respectively carried by the portions 1a and 1b of the supporting frame 1. Thus, as may be seen from FIG. 2 a shaft 31 is carried by the frame portion la, and this shaft is supported for turning movement by the frame portion 1a and fixedly carries a sprocket wheel 32, a transporting roll 33, and a scoring disc 34. The sprocket chain 23 cooperates with the sprocket wheel 32 for rotating the latter and the shaft 31 therewith. The machine frame it also turnably supports a shaft 35 which fixedly carries a pair of lever arms 36 and 36, and the lever arms 36 turnably support a grooved scoring disc 37 which receives in its peripheral groove the periphery of the scoring disc 34. Thus, the periphery of the disc 34 extends into the groove 37 of the disc 37. The lever arm 36 carries a counterpressure roll 38 which cooperates with the transporting roll 33 for transporting the blank. The discs 37 and 38 are pressed downwardly toward the discs 34 and 33, respectively, by suitable springs or weights. As was mentioned above, a mirror image of this structure at the left of FIG. 2 is provided at the right, as shown in FIG. 2, for simultaneously transporting and scoring the opposite end portion of the bag blank. The frame portions 1a and lb are adjustable transversely to the longitudinal axis of the machine so that the scoring means shown in FIG. 2 may be adjusted for relatively long blanks as well as for relatively short blanks.

Thus, as the blank is transported through the structure shown in FIG. 2, the pair of discs 34 will press grooves into the blank, and the end portions of the blank which respectively extend beyond these grooves will be engaged by the guides 8 of FIG. 1 so as to be deflected thereby respectively through angles of less than 90 into the op positely inclined planes E and E indicated in FIG. 3.

' With the end portions of the moving blank located in these planes E and E, the end portions of the blank are engaged by the rotating nozzles 39 and 39 of the end opening means shown in FIG. 3. Thus, a pair of suction nozzles 39 and 39 operate on one of the end portions of the bag blank, while another pair of suction nozzles 39 and 3E operate on the other of the deflected blank end portions. Each pair of cooperating suction nozzles 3% and 39 are respectively carried by a pair of hollow shafts 4t and 443 which are respectively placed in communication with any suitable vacuum pump or the like for providing the suction. Each pair of shafts 4t and 4d are supported for rotation about their axes, respectively, by a triangular frame member 41, and the shafts 4t and so extend parallel to the plane E or E. The frame members 4-1 are respectively arranged on a pair of transverse supporting frame members 49 and 49' carried by the frame portions la and la, on the one hand, and lb and lb, on the other hand, as is evident from FIG. 3. The shafts it? and 4d at each side of the structure shown in FIG. 3 are driven from the drive shaft 21 through the bevel gears 24 and the bevel gear The bevel gear drive 42 is connected with the gear 42 through any suitable gearing or the like. With this arrangement the pairs of cooperating suction nozzles 39 and 39' move together with'the end portions of the bag and simultaneously pull the opposite side walls of each end portion apart from each other so as to open and spread apart each of the end portions of the blank. The pairs of cooperating nozzles 39 and 39 simultaneously rotate in opposite directions. The details of the structure shown in FIG. 3, except for the inclined mounting thereof, are known in and of themselves and are shown in US. Patent 2,707,421, particularly in FIGS. 1 and thereof.

After moving beyond the end opening means 9 of FIG. 3, the blank whose open ends are still maintained in the oppositely inclined planes E and E reaches the pair of folding means shown in FIG. 4. Each of the folding means 10 shown in FIG. 4 includes a pair of folding fingers 43 and 43' of a folding device the details of which also are shown in US. Patent 2,707,421, al though in the latter patent the folding devices are arranged in vertical rather than inclined planes. As is explained in the latter patent, the folding fingers 43 and 43 enter into the open end of the bag blank. These folding fingers 43 and 43' at each side of the structure shown in FIG. 4 are carried, respectively, by a pair of endless sprocket chains 44 and 44', and the folding fingers form parts of cranks which have ends located in suitably curved grooves of the guides 45 and 45' so that the fingers 43 and 43 are automatically turned in proper synchronism with each other at the proper moments so as to fold each end portion of the bag in the desired manner. The fingers 43 and 43 at each side of the structure of FIG. 4 turn during operation on each of the end portions of the blank in the plane Q or Q, and the end portions of the blank are folded into these planes Q and Q, respectively, which are respectively perpendicular to the planes E and E, as is indicated in FIG. 4.

Before reaching the spreading means of FIG. 3 and the folding means of FIG. 4 each end portion ofthe blank includes a pair of fiat side wall portions located directly next to each other. The end opening means of FlG. 3 separates these side walls portions of each end portion from each other, and the folding means of FIG. 4 folds each of these end portions into the plane Q or Q which is perpendicular to the plane E and E, respectively. During this folding by the structure of FIG. 4, each of the side wall portions of each end portion of the blank is folded into a trapezoidal portion and a pair of triangular end portions overlapping the triangular end portions of the trapezoidal portion, and of course the triangular portions of one of the side walls of the end portion of the blank form continuations of the triangular portions of the other side walls of the end portion of the blank. In this way, after being worked upon by the folding means of FIG. 4, the free edge at each end portion of the blank defines a rectangle.

Thus, the pair of folding means is of FIG. 4foldsthe end portions of the blank into partially complete bag ends which are respectively located in the planes Q and Q of FIG. 4, and these partially complete bag end portions need only be turned through a relatively small angle into a horizontal plane in order to receive glue.. Thus, the right bag end portion of FIG. 4 which is partially complete and which is located in the plane Q is turned in a clockwise direction, as viewed in FIG. 4, into a. horizontal plane through an angle of less than while the left partially complete end portion of the blank of FIG. 4 which is located in the plane Q is turned in a counterclockwise direction, as viewed in FIG. 4, through a relativley small acute angle into a horizontal plane. It Will be noted that the end portions of the blank are spaced from each other by the distance aindicated in FIG. 4. With this extremely short bag length, it is pos sible to provide partially complete end portions in the planes Q and Q which, when they are turned in the above-described manner into the horizontal working plane, touch each other at their inner edges.

The turnable folding fingers 43, 43 are supported for turning movement by bearing members 48 and 43' which are carried by the sprocket chains which cooperate with,

the sprocket wheels 44 and 44, and while the fingers 43 and 3 turn so as to fold the end portion of the bag, they are located in the plane Q or Q and they move together with the bag blank along the path of movement through which the blank is moved by the transporting means,

The grooved guides 45 and 45' control the turning of the folding fingers 43 and 43, as indicated in U.S. Patent 2,707,421, so that these fingers 43 and 43' turn into the opened bag end portion at the right moment, and then during the continued movement of the blank fold the access;

7 blank end portion in the above-described manner, and finally after this folding the fingers turn away from the blank. In order that the two sets of folding fingers may be located in the planes Q and Q, respectively, and work on the deflected bag end portions in these planes, the pair of folding means 10 are mounted at their side walis 51 and 51' on the inclined supporting surfaces 46 of the traverse frame members 5% and 59' carried by the frame portions in, 1a and 1b, 1b and the upper plates 51' are carried by support members 47 which are fixed to the outer side frame members in and Rh. Thus, with this arrangement it is possible for the shafts of the sprocket wheels 44 and 44 to extend parallel to the planes Q and Q and perpendicular to the planes E and B. As a result of the inclined positioning of the pair of folding means 10, the inner plate portions 1a and 1b of the machine frame can be located directly next to each other in the manner illustrated in FIG. 4 without any conflict between the pair of closely arranged folding means. In this way it is possible to provide for an extremely short bag length a which is so short that when the partially complete end portions of the bag are turned into the horizontal plane their inner edges touch each other at the center of the blank, as was pointed out above.

The pair of glue-applying means 14 and 15 referred to above are illustrated in simplified fashion in FIGS. 5 and 6, and of course, as was pointed out above, the partially complete end portions of the blank are turned into the horizontally working plane before reaching the pair of glue-applying means shown in FIGS, 5 and 6, respectively. As may be seen from FlGS. l and 6, a glue container '52 is carried by a carrier member 53 which is supported by the frame part 11), and it will be noted from FIG. 6 that the carrier 53 extends over and beyond the frame part 1a. A glue-transporting roller 54 extends into the container 52 to receive a coating of glue, and this roller 54 is supported for rotation on the one hand by a bearing member 55' carried by the carrier member 53 and on the other hand by a bearing member 55 carried by the frame part 1b. A pair of bearing members 56 and 56 are respectively located above the bearing members 55 and 55, and these bearing members 56 and 56' support a shaft 57 for rotation about its axis, and this shaft 57 carries the glue-transferring and applying means 58 which applies the glue directly to one of the partially complete end portions of the bag. A pair of pressure rolls 59 and 59' are located on the glue-applying roll 58, and these rolls 59 and 59' are turnably supported by shafts 6t) and 60, respectively, which are carried by lever arms 61 and 61 which in turn are fixed to the shaft 62 which is supported for rotation about its axis by the machine frame. As is shown in FIGS. 1 and 6 a control lever 63 is fixed to the shaft 62 and cooperates with a cam 64. Through a drive 65, 65' the cam 64 is rotated in such a way that the shaft 62 is periodically turned through a predetermined angle through the lever 63 which cooperates directly with the cam 64, and the rolls 59 and 59 are only pressed downwardly when the blank is located betwen these rolls and the glue-applying roll means 58. When the blank is not located beneath the rolls 59 and 59' these rolls are raised away from the roll means 58 so that the rolls 59 and 59' cannot pick up any glue.

The glue-applying means 14 shown in FIG. 5 is of the same construction as that of FIG. 6 and is simply a mirror image thereof, the upper structure which includes the rolls 59 and 59 and the structure for controlling the same being omitted from FIG. 5 for the sake of simplicity. It will be noted that in FIG. 5 the carrier 53 extends from the frame member fa to the right over and beyond the frame member 11). Thus, the glue-applying means 15 is arranged on the support means along the path of movement of the blank behind the glue-applying means 14 (see FIG. 1) and in partially overlapping relation therewith (compare FIGS. 5 and 6), so that in this way in spite of the size of thepair of glue-applying means they may nevertheless apply the glue to the relatively short bag length even though these glue-applying means in themselves are relatively Wide as compared to the length of the bag and could not be located beside each other.

The pair of scoring means 16 shown in FIG. 7 are constructed similarly to the scoring means of FIG. 2. The pair of scoring means 16 are identical and are mirror images of each other, so that oniy the left scoring means of FIG. 7 will be described in detail. This left scoring means 16 of FIG. 7 is carried by the frame parts 1a and 1a, while the right scoring means is carried by the frame parts 1b and 1b. Each of the scoring means includes a shaft 66 which is supported by the frame members for rotation about its axis, and the shaft 66 carries a pair of scoring discs 67 and 67' Whose peripheries respectively extend into the scoring grooves of a pair of cooperating scoring rolls 68 and 68, respectively. These rolls are tnrnably supported by lever members 69 and 69, respectively, which are carried by an upper shaft which is turnably supported by the frame of the machine, and of course the rolls 68 and 68' are urged downwardly by suitable springs or weights.

The distance between the pair of scoring discs 67 and 67 corresponds to onehalf the width of the partially complete bag end portion and is centrally arranged with respect to the partially complete bag end portion, so that the scoring means 16 provides on each bag end portion a pair of scoring lines beyond which are located flaps which can thereafter be folded inwardly against each other and against the central part of the bag end portion along these scoring lines so as to provide the completed bag end. In this way a closed completely folded bag end is provided. As was mentioned above, the structure at the right of FIG. 7 is a mirror image of that at the left of FIG. 7, andbefore the pair of flaps of the right end portion of the blank which passes through the right scoring means of FIG. 7 are folded inwardly against each other a filling tube is located between and glued together with the flaps, in a known way, so that the bag may be filled through such a tube. Thus, the right end portion of the structure of FIG. 7 forms the top end of the bag, while the left portion of the structure of FIG. 7 forms the bottom of the bag. The devices for folding over the flaps at the partially complete bag end portions as well as for including a filling tube in one of the end portions of the bag are well known and are not further described or shown.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of bag manufacturing machines differing from the types described above.

While the invention has been illustrated and described as embodied in machines for forming the ends of a bag, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a machine for forming folded top and bottom ends of a bag, in combination, support means; transporting means carried by said support means for transporting a fiat tubular bag-forming blank along a predetermined path in a predetermined plane in which said blank is located, said blank having a pair of opposite end portions; means for deflecting said end portions of said blank while it is transported in said predetermined plane by said transporting means through substantially less than 90 into a pair of oppositely inclined planes which make angles of substantially less than 90 with said predetermined plane, respectively; and a pair of means, each inclined with respect to said predetermined plane, for folding the deflected end portions of the blank into partially complete bag ends while said end portions are in said pair of oppositely inclined planes, the angle of said inclined planes being less than 90 with respect to said predetermined plane by an amount which renders it possible for said pair of folding means to be adjacent to each other in a plane transverse to said predetermined path and to act simultaneously on the partially complete bag ends even in the case where the length of the bag is so short that the completed bag ends touch each other.

2. In a machine for forming folded top and bottom ends of a bag, in combination, support means; transporting means for transporting a flat tubular bag-forming blank having a pair of opposite end portions along a predetermined path in a predetermined plane in which said flat blank is located; deflecting means carried by said support means for deflecting said end portions of said blank from said predetermined plane through substantially less than 90 respectively into a pair of oppositely inclined planes which make substantially less than 90 with said predetermined plane, while said blank is being transported by said transporting means; and a pair of folding means carried by said support means, each inclined with respect to said predetermined plane, and each acting on one of the deflected end portions of the blank while said deflected end portions are in said pair of oppositely inclined planes, respectively, for folding said end portions into partially complete top and bottom bag ends, respectively, the angle of said inclined planes being less than 90 with respect to said predetermined plane by an amount which renders it possible for said pair of folding means to be adjacent to each other in a plane transverse to said predetermined path and to act simultaneously on the partially complete bag ends even in the case where the length of the bag is so short that the completed bag ends touch each other.

3. In a machine for forming folded top and bottom ends of a bag, in combination, support means; transporting means for transporting a fiat tubular bag-forming blank having a pair of opposite end portions along a predetermined path in a predetermined plane in which said flat blank is located; deflecting means carried by said support means for deflecting said end portions of said blank from said predetermined plane through substantially less than 90 respectively into a pair of oppositely inclined planes which make substantially less than 90 with said predetermined plane, while said blank is being transported by said transporting means; and a pair of folding means carried by said support means, each inclined with respect to said predetermined plane, and each acting on one of the deflected end portions of the blank while said deflected end portions are in said pair of oppositely inclined planes, respectively, for folding said end portions into partially complete top and bottom bag ends, respectively, said pair of folding means being located beside and closely adjacent to each other in a plane transverse to said predetermined path, the angle of said inclined planes being less than 90 with respect to said predetermined plane by an amount which renders it possible for the folding means to act simultaneously on the partially complete bag ends even in the case where the length of the bag is so short that the completed bag ends touch each other.

4. In a machine for forming folded top and bottom ends of a bag, in combination, support means; transporting means for transporting a flat tubular bag-forming blank having a pair of opposite end portions along a predetermined path in a predetermined plane in which said flat blank is located; deflecting means carried by said l0 support means for deflecting the end portions of said blank from said predetermined plane through substantially less than respectively into apair of oppositely inclined planes which make substantially less than 90 with said predetermined plane, while said blank is being transported by said transporting means; a pair of folding means carried by said support means for folding the deflected end portions of said blank while the latter is being transported by said transporting means into a pair of partially complete bag ends, each of said folding means being inclined with respect to said predetermined plane and both said folding means being located in a plane transverse to said predetermined path; and a pair of glue applying means located along said path after said pair of folding means for applying glue to said partially complete bag ends, said pair of glue applying means being arranged one behind the other along said path in partly overlapping relationship.

5. In a machine for forming folded top and bottom ends of a bag, in combination, support means; transporting means for transporting a tubular flat bag-forming blank having a pair of opposite end portions along a predetermined path in a predetermined plane in which said blank is located; deflecting means carried by said support means for simultaneously deflecting said end portions of said blank through substantially less than 90 into a pair of oppositely inclined planes, respectively, which make substantially less than 90 with said predetermined plane, while said blank is being transported by said transporting means; a pair of folding means carried by said support means after said deflecting means along said path, each of said folding means being inclined with respect to said predetermined plane and both simultaneously acting on the deflected end portions of said blank While said end portions are in said pair of oppositely inclined planes, respectively, for folding said end portions respectively into a pair of partially complete bag ends, the angle of said inclined planes being less than 90 with respect to said predetermined plane by an amount which renders it possible for said pair of folding means to be adjacent to each other in a plane transverse to said predetermined path and to act simultaneously on the partially complete bag ends even in the case where the length of the bag is so short that the completed bag ends touch each other; and a pair of glue applying means carried by said support means along said predetermined path after said pair of folding means for successively applying glue to said partial complete bag ends, said pair of glue applying means being arranged one behind the other along said path and in partly overlapping relationship.

6. In a machine for forming top and bottom ends of a bag, in combination, support means; transporting means carried by said support means for transporting a flat tubular bag-forming blank having a pair of opposite open end portions along a predetermined path in a predetermined plane in which said flat blank is located; deflecting means carried by said support means for deflecting said end portions of said blank, while the latter is being transported along said path by said transporting means, respectively through substantially less than 90 into a pair of oppositely inclined planes; opening means carried by said support means after said deflecting means for opening said end portions of said bag while said end portions are in said pair of oppositely inclined planes; a pair of folding means each inclined with respect to said predetermined plane and both carried by said support means along said path after said opening means for simultaneously folding the open end portions of the bag while said end portions are still in said pair of oppositely inclined planes into a pair of partially complete bag ends, respectively, the angle of said inclined planes being less than 90 with respect to said predetermined plane by an amount which renders it possible for said pair of folding means to be adjacent to each other in a plane transverse to said predetermined path and act simultaneously on the partially complete bag ends even in the case where the length of the bag is so short that the completed bag ends touch each other; and a pair of glue applying means carried by said support means after said pair of folding means along said path for applying glue to said partially complete bag ends, said pair of glue applying means being arranged one behind the other along said path in partly overlapping relationship.

References Cited inthe file of this patent UNITED STATES PATENTS Cosgrove Mar. 15, 1932 Marchev Oct. 1, 1940 Burroughs Oct. 2, 1951 Grarnegna June 9, 1953 FOREIGN PATENTS Germany Dec. 29, 1936

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