US3129871A - Bags - Google Patents

Description

A. F. BECKER Apr-i121, 1964 BAGS 3 Sheets-Sheet 1 Filed Sept. 26, 1961 April 21, 1964 A. F. BECKER BAGS Filed Sept. 26, 1961 5 Sheets-Sheet 2 April 21, 1964 A. F. BECKER BAGS Filed Sept. 26, 1961 i 5 Sheets-Sheet 3 United States Patent fice 3,129,871 BAGS Arnold F. Becker, San Pedro, Calif., assignor to Bemis Bro. Bag Company, St. Louis, Mo., a corporation of Missouri Filed Sept. 26, 1961, Ser. No. 140,810 2 Claims. (Ci. 22962.5)

This invention relates to valve bags, and more particularly to pasted valve bags and the manufacture thereof.

Among the several objects of the invention may be noted the provision of a pasted valve bag with an improved tuck-in valve sleeve having a cuff which provides ample space for tuck-in of the sleeve after the bag has been filled; and the provision of a method of manufacturing such bags in which the sleeves are formed from a continuous web of sleeve material and combined with the bags in a continuous operation. Other objects and features will be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the constructions and methods hereinafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

FIG. 1 is a schematic side elevation showing the manufacture of bags in accordance with this invention;

FIG. 2 is a perspective illustrating certain steps performed in FIG. 1;

FIG. 3 is a top plan view of a string of sleeves made according to FIGS. 1 and 2 and showing a sleeve segmented from the string;

FIG. 4 is a bottom plan of FIG. 3;

FIGS. 5 and 6 are enlarged detail views;

FIG. 7 is a schematic plan view showing bag tubes being fed through a sidewise bottomer and having sleeves applied thereto; and

FIG. 8 is an enlarged section through a completed bag taken in effect on line 88 of FIG. 7.

Corresponding reference characters indicate corresponding parts throughout the several view of the drawings.

Referring to the drawings, there is generally indicated at 1 in FIGS. 1 and 7 a bag bottomer of a type such as is referred to in the art as a sidewise bottomer. It will be understood that in this type of bottomer, flat bag tubes B are fed forward sidewise (as distinguished from lengthwise) one after another, and the ends of each tube are formed with pasted closures. Such a bottomer is shown, for example, in Rawe U.S. Patent 2,707,421. FIG.7 shows one end of each tube of such a series of tubes being fed forward one after another through the sidewise bot tomer, this end being the end including the corner of the tube where a valve is to be formed and a valve sleeve S applied. As shown for the tube at the left of FIG. 7, the end of the tube is opened up to form end flaps 3 and 5 and first and second side flaps 7 and 9, and a pattern of paste P is applied. End flap 3 may be referred to as the valve flap, being located at the valve corner of the bag tube. The paste pattern includes stripes extending across flaps 3 and 5 lengthwise of the bag and a stripe extending across side flap 9 transversely of the bag. The stripe extending across valve flap 3 has a relatively narrow portion P1 extending closely adjacent the inner end edge of flap 3 between lines L1 and L2 on which flaps 7 and 9 are subsequently folded to complete the closure. The flaps 3 and 5 are oriented lengthwise as regards the direction of 3,129,871 Patented Apr. 21, 1964 plied to valve flap 3. In FIG. 7, a sleeve S has been applied to the bag tube at the center. Then, as shown for the tube at the right of FIG. 7, side flap 7 is folded over on line L1 on the sleeve S and end flap 5, and side flap 9 is folded over on line L2 on side flap 7 to complete vthe formation of the closure.

Sleeve S is a tuck-in sleeve, i.e., a sleeve which extends out of the bag at the valve corner of the bag, an outer part of the sleeve being folded under and tucked in between the rernainder of the sleeve and valve flap 3 after the bag has been filled. In accordance with this invention, sleeve S is also a so-called cuffed sleeve, having a cuff C by means of which it is secured by pasting to the inner end of the valve flap 3 in such manner as to provide ample space underneath the sleeve for tucking in the folded outer portion of the sleeve.

As shown in FIGS. 1 and 2, sleeves S are formed from a continuous web W of suitable valve sleeve material, which, for example, may be creped kraft paper. At 11 in FIG. 1 is indicated a draw roll for drawing the web from a supply roll R. Idler rolls such as indicated at 13 are provided for guiding the web around the draw roll. The web has a width somewhat greater than twice the Width of the sleeves to be formed therefrom. From the second idler roll 13, the web passes through a cuff cutter generally indicated at 15 which functions to make cuff cuts such as generally indicated at 17 in the web recurring at valve sleeve length intervals longitudinally of the web. Each cuff cut defines a cuff C. The cuff cutter essentially comprises a rotary knife 19 and a fixed knife 21 formed to make cuff cuts of the desired shape, as next described.

As shown in FIGS. 2 and 5 each cuff cut 17 is generally of broad U-shape, including a curved base cut 23 extending transversely of the web, relatively short side cuts each designated 25 extending generally longitudinally of the Web, and outwardly curved wing cuts 27 at the ends of side cuts 25. The latter trail the base portion 23 as regards the direction of travel of the web, which is indicated by an arrow in FIGS. 1 and 2, and wing cuts 27 are at the trailing ends of the side cuts. The side cuts :25 are spaced transversely of the web a distance somewhat greater than the width of the sleeves S to be formed from the web, and are equally spaced on opposite sides of a line corresponding to the longitudinal center line of the sleeves.

From the cuff cutter 15 the Web W (now having cuff cuts 17 therein) passes through a creaser comprising upper and lower rotary creasing members 29 and 31 (see FIG. 1) which function to form a crease 33 (see FIG. 2) extending transversely across the web between the ends of the wing cuts 27 of each cuff out. As shown in FIGS. 1 and 2, web W travels horizontally through the creasing members, and thence passes around a horizontal idler roll 35 and vertically downward. In passing downward around idler roll 35, it passes between idler roll 35 and a cuff-folding roll 37. As appears from FIG. 2, when the web W changes direction from horizontal to vertical in passing around idler roll 35, each cuff C tends to continue on in horizontal direction and, for a brief instant, projects out over the cuff-folding roll 37. Then, as the cuff travels down with the web, it is folded upward on the respective crease 33 and flattened back against the web. As a result of folding back the cuffs, openings 0 are left in the web.

The web W, with the folded-back cuffs C, then travels .around an idler roll 39 from which it passes to an adjustable cuff register roll 41 and thence to a pastor generally indicated at 43. This paster comprises a paste wheel 45 rotating in a paste reservoir 47 and adapted to apply a stripe of paste 49 (see FIG. 2) to one margin of web W. At.51 in FIG. 1 is generally indicated an endless belt conveyor trained around pulleys 53 and 55 to have an upper reach inclined downward in forward direction.

Pulley 53 is located adjacent the paste wheel 45. The web travels upward between the paste Wheel and pulley 53. The latter is positively driven to drive the belt con veyor in the direction indicated by the arrow on the conveyor in FIG. 1. The web passes around the portion of the conveyor trained around pulley 53 and under a rotary creaser 57. Pulley 53 is formed as a female creaser and rotary creaser 57 acts in conjunction therewith to form two longitudinally extending creases 59 (see FIGS. 2 and 6) in the web and in each cuff C located slightly inward from side cuts 25 of the cuff cuts 17. These creases 59 define the width of sleeves S. The upper reach of the conveyor passes over a table 61. As the web travels along with the upper reach of the conveyor over the table, the side portions 63 and 65 of the web lying outward of creases 59 are folded over at these creases by folding means such as indicated at 67 in FIG. 1 to bring the margins of the web into overlapping relation and to cause them to become pasted together by the stripe of paste 49. The web is thereby converted into a series or string of integrally connected valve sleeves S. In the string, each sleeve S comprises a flat tube, one wall of which is constituted by side portions 63 and 65 and the other wall of which is designated 69. Creases 59, on which portions 63 and 65 are folded over, define the side edges of the sleeve or tube S. The sleeve or tube S has a longitudinal tube seam '71 where the margins of the web are overlapped and adhered together by paste 49. At one end (the leading end) of each sleeve or tube S is the cuff C, which is folded back upon the sleeve or tube S. Cuts 25 are located in wall 63, 65 of the sleeve or tube S, on opposite sides of the longitudinal seam 71, and the cuff C extends from one cut 25 around one side edge 59 of the sleeve or tube S, across wall 69 of the tube, and around the other side edge 59 of the sleeve or tube S to the other out 25. The narrow end portions of the cuff which lie on the outside of wall 63, 65 are designated C1. Wall 63, 65 of each sleeve or tube S has an extension 73 projecting beyond the cuifed end of the sleeve or tube S, each extension 73 being integrally connected along a line such as indicated in phantom at 75 in FIGS. 24 to the next sleeve or tube S in the string.

The string of valve sleeves S travels off the leading end of the upper reach of conveyor 51, passes under an idler roll 77 and between a pair of draw rolls 79. Thence it passes through a cutter generally indicated at 81 which functions almost completely but not fully to sever the string on lines 75. For example, cutter 81 functions to cut the string at 75a, "75b and 756 as indicated in FIGS.

3 and 4, leaving narrow tongues of the web material such as indicated at 75d interconnecting the individual sleeves S in the string. Cutter 81 essentially comprises a rotary knife 83 and a fixed knife 85 formed to make incomplete cuts as described.

The string passes from the cutter 81 between so-called forwarding rolls 87 and thence between so-called snap-off rolls 8). Both the forwarding rolls and the snap-01f rolls are positively driven, but the snap-off rolls 89 are driven at a faster speed than the forwarding rolls 87 so as to cause each successive sleeve S exiting from the nip of the forwarding rolls to be snapped off at the line 75, the narrow tongues 75d tearing apart as appears in FIGS. 2-4. Thus, the sleeves S are segmented from the string.

At 91 is indicated an endless chain trained around sprockets 93, 95, 97 and 99. This chain is driven in the direction indicated by the arrow in FIG. 1. It carries a series of sleeve gripper units each generally indicated at 181. Three such gripper units are shown in FIG. 1. These are spaced at equal intervals along the length of the chain. Each gripper unit comprises a jaw 103 carried by the chain and fixed against movement relative to the chain, and a jaw 105 pivoted at 1497 on the chain for pivotal movement relative to the chain between open and closed position relative to the jaw 103. The sprockets are so located that the chain has a lower forwardly travelling reach generally aligned with the path of the string of sleeves S. As each gripper unit 101 comes around with the chain around the sprocket 93 at the trailing end of the lower reach of the chain, the pivoted jaw of the unit is open as appears in FIG. 1 and the leading end of a sleeve S segmented from the string as previously described enters the gripper unit, the sleeve being forwarded for entry of its leading end into the gripper unit by a lower forwarding sector 109 and an upper forwarding roll 111. The latter is coaxial with sprocket 93. The leading end of the sleeve comes under the fixed jaw 103. Then the pivoted jaw 105 swings closed to grip the sleeve. The action of the pivoted jaw may be under control of any suitable means, such as a fixed cam track cooperating with a cam follower on the pivoted jaw.

A sleeve S gripped .by a gripper unit 16d on chain 91 is carried along with the lower reach of the chain and delivered into position on end flap 3 of the partially formed closure on one of the series of bags B being fed forward through the bottomer 1. When the sleeve has been carried into proper position on the end flap 3, the pivoted jaw 195 of the gripper unit opens to release the sleeve, and the gripper unit travels up and away with the chain around sprocket 95. An endless belt 113 trained around pulleys 115 and 117 (the former being coaxial with sprocket 99) holds the sleeve in position on the end flap 3 after the pivoted jaw 105 has opened.

The sleeve forming and delivering means above described is driven in synchronism with the bottomer 1 for delivering a sleeve S for each bag tube B fed through the bottomer, with the delivery of the sleeves phased with the feed of bag tubes so that each sleeve is delivered onto valve flap 3 of a bag tube with the cuff C of the sleeve overlying the inner end margin of the valve flap 3, i.e., with the crease 33 substantially in register with the inner end edge 119 of the valve flap 3. It will be observed that each sleeve is delivered with its wall 69 and culf C on the bottom for this purpose. Also, the path of the web W and the string of sleeves S into which the web is formed, and of the individual sleeves segmented from the string, is registered with the path of the bag tubes being fed through the bottomer so that the longitudinal center line of each sleeve delivered to a bag tube is substantially in register with the center line of the valve flap 3.

Draw roll 11, rotary knife 19, rotary creaser members 29 and 31, culf-folding roll 37, rotary knife 83 and forwarding rolls 87 are all driven, in synchronism with bottomer 1, at such speed as to produce one sleeve for each bag tube fed through the bottomer. The drive for these elements may be via a change gear from the bottomer, permitting change of speeds by changing gears for producing sleeves of different length. Paste wheel 45, pulley and female creaser 53, draw rolls 79 and draw roll 11 are driven off the output of the change gear via a variable speed drive which enables adjustment of tension on the sleeve material. Snap-Off rolls 89, forwarding sector 109 and forwarding roll 111, chain 91 and belt 113 are driven at a speed such as to deliver the sleeves at the same speed as the speed of bag tube feed through bottomer 1. Cuff register roll 4 1 is adjustable for varying the length of sleeve material between cuff cutter l5 and sleeve cutter 81 to provide for proper registration of cuff cut and sleeve cut. Draw rolls 79, cutter 81 and forwarding rolls 87 are part of a unit 121 which may be adjusted in position so that the distance between forwarding rolls 87 and snapoif rolls 89 may be varied for various sleeve lengths.

From the above, it will be apparent that each completed bag has a closure at one end comprising the inwardly directed end flaps 3 and 5 and the first and second side flaps 7 and 9, with end flap 3 constituting a valve flap. Sleeve S, which is a tuck-in sleeve, and which comprises a flat tube, overlies the valve flap 3. The first side flap 7 is folded over on the outer wall 63, 65 of the sleeve on tube S and the end flap 5, and the second side flap 9 is J folded over on the first side flap 7 and adhered thereto by paste P. The sleeve or tube S has the pair of cuts 25 extending inward from one end thereof defining the cufi C, this cufi being folded back on the outside of the sleeve or tube S. The sleeve or tube S is positioned on valve flap 3 With cuff C overlying the margin of flap 3 at the inner end of flap 3 (see FIG. 8) with the sleeve or tube S extending outward over the flap 3. Cufi C is adhered to the flap 3 by the paste at P1.

More particularly, the cuts 25 are located in the outer Wall 63, 65 of the sleeve or tube S, and the cuff C extends from one cut 25 around one side edge 59 of the sleeve or tube S, across the inner Wall 69 of the sleeve or tube S, and around the other side edge 59 to the other out 25. The sleeve or tube S actually consists of a rectangular section of the valve sleeve material W folded to form the sleeve or tube S with overlapping adhered-together margins in the outer Wall 63, 65 forming the longitudinal seam 71, cuts 2 being located on opposite sides of this seam (see FIGS. 2 and 3). The folding back of the cuff leaves extension 73 of wall 63, 65 projecting inward beyond crease 33 which is located at the inner edge of flap 3.

The bag is adapted to be filled by entering a filling spout in the sleeve S and blowing the material with which the bag is to be filled (such as a pulverized or granulated material) into the bag through the spout. After the bag has been filled, it is taken off the spout, and the outer half of the sleeve S is folded under and tucked in underneath the inner half of the sleeve. With the cult C, full tuck-in to the point where the original outer end of the sleeve is entered between the cuff C and the overlying portion of the inner Wall (the wall 69) of the sleeve is readily accomplished. That is, the cufi C provides space for tucking the sleeve in as far as the inner end edge of flap 3 conceivably to the point where the end of the sleeve would engage crease 33. In this respect, it will be observed that the paste P1 is applied in a relatively narrow band (see FIG. 7) no Wider than cufi C, and does not extend outward beyond the edge of the cuif so as to avoid having the bottom wall of the sleeve as viewed in FIG. 8 stuck to flap 3. If it were stuck to flap 3, full tuck-in of the sleeve would be blocked.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

AS various changes could be made in the above con structions and methods without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A valve bag having a closure at one end comprising inwardly directed end flaps and first and second side flaps, one of said end flaps constituting a valve flap, a tuck-in valve sleeve comprising a fiat tube overlying said valve flap, said first side flap being folded over upon the outer Wall of said tube and the other end flap and being adhered thereto, said second side flap being folded over upon said first side flap and adhered thereto, said tube having a pair of cuts located in its outer wall extending inward from one end thereof defining a cutf, said cuif being folded back on the outside of the tube and extending from one cut around one side edge of the tube, across the inner wall of the tube, and around the other side edge of the tube to the other cut, said tube being positioned on said valve flap with said cuff overlying the margin of the valve flap at the inner end of the valve flap with the tube extending outward over the valve flap, and said cuff being adhered to the valve flap.

2. A valve bag as set forth in claim 1 wherein said tube consists of a rectangular section of valve sleeve material folded to form the tube with overlapping adhered-together margins in the outer Wall of the tube forming a longitudinal tube seam, said cuts being located on opposite sides of said seam.

References Cited in the file of this patent UNITED STATES PATENTS 2,660,100 Doyle Nov. 24, 1953 2,695,746 Woodward Nov. 30, 1954 2,955,517 Honsel Oct. 11, 1960 2,968,432 Craighead Ian. 17, 1961 2,977,038 La Fave Mar. 28, 1961 3,022,932 Vines Feb. 27, 1962 FOREIGN PATENTS 806,623 Germany June 14,

Claims (1)

1. A VALVE BAG HAVING A CLOSURE AT ONE END COMPRISING INWARDLY DIRECTED END FLAPS AND FIRST AND SECOND SIDE FLAPS, ONE OF SAID END FLAPS CONSTITUTING A VALVE FLAP, A TUCK-IN VALVE SLEEVE COMPRISING A FLAT TUBE OVERLYING SAID VALVE FLAP, SAID FIRST SIDE FLAP BEING FOLDED OVER UPON THE OUTER WALL OF SAID TUBE AND THE OTHER END FLAP AND BEING ADHERED THERETO, SAID SECOND SIDE FLAP BEING FOLDED OVER UPON SAID FIRST SIDE FLAP AND ADHERED THERETO, SAID TUBE HAVING A PAIR OF CUTS LOCATED IN ITS OUTER WALL EXTENDING INWARD FROM ONE END THEREOF DEFINING A CUFF, SAID CUFF BEING FOLDED BACK ON THE OUTSIDE OF THE TUBE AND EXTENDING FROM ONE CUT AROUND ONE SIDE EDGE OF THE TUBE, ACROSS THE INNER WALL OF THE TUBE, AND AROUND THE OTHER SIDE EDGE OF THE TUBE TO THE OTHER CUT, SAID TUBE BEING POSITIONED ON SAID VALVE FLAP WITH SAID CUFF OVERLYING THE MARGIN FO THE VALVE FLAP AT THE INNER END OF THE VALVE FLAP WITH THE TUBE EXTENDING OUTWARD OVER THE VALVE FLAP, AND SAID CUFF BEING ADHERED TO THE VALVE FLAP.

Images