US2734431A - Machine for making window bags - Google Patents

Description

Feb. 14, 1956 H. L. BARTELT MACHINE FOR MAKING WINDOW BAGS Filed April 14, 1952 5 Sheets-Sheet 1 Feb. 14. 1956 H. L.. BARTELT MACHINE FOR MAKING WINDOW BAGS 3 Sheets-Sheet 2 Filed April 14, 1952 Feb. 14, 1956 Filed April 14, 19,52

H. l.. BARTELT MACHINE FOR MAKING WINDOW BAGS 3 Sheets-Sheet 3 Wou/'old bl. )"5 QAM/pw' man* frommen/f UIltCd StatCS ce 2,734,431

tenfed Feb. 14, 195s- MAGHINE FOR- WINDGW ABAGS par lif'fa Donald E. Banen Airplicaiion April .14; 1952; serial No.V v22:2;119 i6 aiii. (iii. "93:5

which between the member and the bracket. During a dwell of the strips, the rise of a cam 50 on the camshaft 25 engages a follower roller 51 carried at the lower end of the lever 42 turning the latter about its pivot against the force of a contractile spring 518, which acts between the frame 24 and the lower end of the lever, and swinging the shoe forward to cross-seal the strips.

Severance of the bags is accomplished herein by two vertical opposed blades 52 and 53 disposed on opposite sides of the strips 18 and 19 and located beyond the feed rollers 29 and 30 at the cutting station 21. The blade 53 is stationary on the frame 24 and the other blade 52 is mounted on the upper end of an upright lever 54 pivoted intermediate its ends on a rock shaft 55. During dwelling of the strips, the rise of a cam 56 on the camshaft 25 engages a follower 57 journaled on the lower end of the lever 54 rocking the latter and swinging the blade 52 toward the blade 53 to cut the strips between the edges of the seal 13a.

As more fully set forth in my prior application, the machine thus far described operates in successive cycles each comprising one revolution of the camshaft 25 to complete the formation of one bag and cut the same olf from the leading end of the strip. In the first part of the cycle, the rollers 29 and 30 are turned to draw material from the roll 35 past the folder 39 and advance the folded strip a distance equal to the width of the bag as determined by the photocell controlled mechanism 33. During the ensuing dwell of the strip, the heated shoe 40 and the cutter 52 are advanced simultaneously to form the cross seal 13a at the station 20 and sever the previously formed seal at the station 21.

In accordance with the present invention, the strip feeding, seal actuating and cut-off mechanisms of the bag forming machine are utilized advantageously to perform the additional functions of forming the window sheet 15, locating the same properly with respect to the window opening 14, sealing the sheet to the wall 11 around the window, and cutting the sheet to a desired length. To accomplish this, a strip 59 of transparent window material is placed alongside the strip 17 before folding of the latter so that the window strip becomes attached to the folded strip by the cross seal 13a and is thus held properly positioned relative to the window 14 preparatory to sealing of the window strip to the outer strip 18 at a subsequent sealing station 60.

,ln order that the transparent strip 59 may enter the bag forming path in the proper relation to the strips 18 and 19, a roll 61 (Figs. l and 2) of transparent strip material is carried on the ends of the arms 37 above the roll 35 where it is unwound and advanced over the straightening rollers 36 alongside the sheet 17 of bag material. The roll 61 is supported by a horizontal shaft 62 the ends of which are journaled in brackets 63 rigid with and depending from the outer ends of the arms 37. Preferably the transparent strip 59 is somewhat less than half as wide as the sheet 17 and is unwound with its left edge, as viewed in Fig. 2, lying along the center of the sheet. The proper relation of the strip and the sheet is obtained by placing the roll 61 on the right side of the shaft 62 and holding it in that position by collars 64 which abut against the ends of the roll and are secured to the shaft by set screws 65.

From the rolls 35 and 61, the sheet 17 and the transparent strip 59 are advanced over the folding mechanism 39 where the sheet is folded longitudinally. Since the transparent strip lies over only one side of the sheet (Fig. 6), it is not folded and, upon leaving the folding mechanism, is disposed between and parallel to the strips 18 and 19 formed by the fold as shown in Figs. 7 and 8.

To form the window 14, a cutter or punch 66 is disposed at a station 58 between the folding mechanism 39 and the cross sealing station 20 where it may be operated by the camshaft 25 during each dwell of the strips 18 and 19 to cut the window in the strip 18. Herein, the

punch comprises a male die 67 (Fig. 3) on the inside of the strip 18 and a female die 68 on the outside, the two dies having complemental cutting surfaces which, when moved together, punch out the hole 14. In the present instance, the hole is generally square and hence the cutting surfaces of the dies are also square as will be seen in Fig. 1.

The male die 67 is mounted on the front of a iiat vertical plate 69 projecting downwardly between the strip 1S and the transparent strip 59 from a horizontal arm 70 fast on an upright bracket 71 which is suitably bolted to the frame 24. Since the window cutting station 58 is in advance of the cross sealing station 20, the strip 18 is free to pass in front of the plate 69 while the strips 19 and 59 pass behind and, therefore, the plate does not interfere with the advance of the strips. The female die 68 is supported by a rigid vertical plate 72 carried on the upper end of an upright lever 73 pivoted intermediate its ends on a shaft 74 secured to the frame. Acting between the frame and the lower portion of the lever is a contractile spring 75 which normally urges the female die away from the male die and holds a follower roller 76 journaled on the lower end of the lever against a cam 77 on the camshaft 25. While the strips are dwelling and the cross sealing and cut-off operations are being performed, a rise 78 of the cam engages the follower roller to swing the lever and move the female die toward the male die thus punching out a portion 79 of the strip 18 to form the window. During the cutting, the plate 69 is held against lateral shifting or bending by a vertical idler roller 80 journaled on the bracket 71 near the bottom of the plate and bearing against the latter through the strips 19 and S9 to serve as a backing.

The cut out portion 79 is ejected through a hole 81 formed in the plate 72 and alined with the dies 67 and 68. lf desired, the ejection may be assisted by air jets tiowing from horizontal passages 82 (Fig. 3) formed in the male die and communicating with a compressed air supply line 83 through a vertical passage 84 in the plate 69. A valve S5 (Fig. 1) is interposed in the supply line and is actuated by a cam 86 on the camshaft 25 in timed relation with the swinging of the lever 73 so that compressed air is admitted to the passages 82 immediately after the portion 79 is punched out by the dies.

In order that the strip 18 may ride over the male die 67 during the next advance without being torn around the window 14 by the die, stripper 678 (Fig. 9) are disposed along the opposite side edges of the die and serve to guide the strip outwardly around the cutting edges of the die. As shown, the strippers 67a are in the form of strips riveted to the plate 69 along their outer edges with their inner edges 67b bent outwardly to lie alongside and ush with the side edges of the die. When the lever 73 swings the female die 68 forwardly, the latter depresses the stripper edges 67ID permitting the dies to punch the window and, as the female die is retracted, the stripper edges spring out even with the male die to present a smooth continuous surface over which the strip 18 moves during the next advance by the feed rollers 29 and 30.

From the punching station 58, the strips 18, 19, and 59 are advanced to the station 60 between the photocell 34 and the cross-sealing station 20 Where the Iseal 16 joining the transparent strip 59 to the strip 18 around the window 14 is formed. To form this seal, the areas of the strip 18 surrounding the window and the corresponding areas of the transparent strip are pressed together between two sealing elements 87 and 88 (Figs. 4 and 5) disposed at the station 60. In the present instance, the scaling element 87 is a fiat hard rubber plate vertically ,suspended from a horizontal arm 89 projecting forwardly from the bracket 47 upstanding from the frame 24 and projects into the bag forming path between the transparent strip 59 and the strip 19. The other element 88 comprises a vertical plate 90 with laterally projecting shoes 91 having sealing srfaces facing the rubber plate S7. The sealing surfaces are arranged to form a square alined with and corresponding in size and shape to the areas of the strips 18 and 59 joined by the seal 16. Electrical heaters 92 are embedded in the plate 90 to heat the shoes 91 above the fusing temperature of the bag material so that, when the sealing element 88 is moved to press' the strips 18 and 59 against the surface of the rubber plate,` the strips are fused together.

The sealing element 88 is mounted on the upper end of a vertical lever which is rocked by a cam onthe camshaft 25 to swing the shoes 91 toward the rubber plate 87. Preferably this sealing element is carried by the same lever 42 which supports the shoe 40 and, for this purpose, is secured to the upper end of a second arm 93 rigid with and upstanding from the sleeve 43o-alongside and in ad- Vance of the lever arm 41. `To make the lever assembly more rigid, the shoes 40 and 91and the plate 90 may be formed as a singlepiece 94 which is mounted on the arms 41 and 93 by .bolts 95 projecting loosely through the arms and threaded into the back of the plate 90. Springs 96 surrounding the bolts and acting between the arms and the plate pertnit yielding of the latter so that the shoes 40 and 91 will engage the strip 18 firmly when pressing the strips being sealed against the sealing element 87.

To maintain the rubber plate 87 vin its vertical position when the seal 16 is being formed, a backing plate 97 is disposed in back of the rubber plate o'n the outside of the stripv19 and acts through the latter to hold the' rub ber plate against any substantial lateral shifting. The baekingplate is supported by the same bracket 47 which supports the backing member 46 and is yieldably mounted onthebracket by bolts 98and springs 99 in the same manner as the backing member ,46is mounted.

With` the transparent strip v59 attached to the strip 18, the feed rollers 29, and 30 unwind a length of the transparentstrip corresponding tothe length of bag material 17` unwound `from the roll 35 and advance the transparentl strip concurrently with the wall strips 18 and 19. Thus each portion of the strip 59 which is to formone of the transparent pieces 15 is maintained in aline'rnent withits associated window 14 by the.A same mechanism which advances the strips 18 and 19. With this construcf tion, the transparent piece is moved along the path of thel machine inexact synchronism with the bag walls 11 and 12 without the use of additional feed mechanism.

When the bags reach the cutting vstation v21, the

transparent strip 59 is cut into lengths corresponding, .to the Width of the transparent pieces 15. By making the transparent pieces of the same vwidth as thebags, the blades 52 and 53 may be usedtocut the strip since the latterpasses between the blades with the strips 18 and 19'. Thus, when the blade 5 2 is swung forward, the transparent .piece is cnt frorn the strip 5 9 at the same time that thevend bag is severedfrom the strips 18 an'd19. In the operation of the machine, the sheet materiall? is nn'wound from the roll 35 and drawn over the folding mechanism 89 to form the two strips 18 and y1 9. ,.Since the, transparent strip 59 isrjoined tothe strip 1 8 by the seals 13a and 16, it is unv'voun'd from the roll 461 at .the s ame time and in synchronismwith the sheet material 1 7. With the transparent strip lying over only one sideof the sheetmateriah it is not folded as it passes throughfth'e folding mechanism fand is disposed between and 'parallel to the strip 18 and 19 upon completion ofthe folding operation. During each revolution of the camshaft 25, ythe three strips are advanced together by the feed rollers through a distance vcorresponding to the width ofthe bags 1 0 and then, d ue to the operationofthe indexing mechanism 38 and the brake 32a,.are stopped.

While the strips Aare dwelling, the rise o f each o f the cams 77, 50, and 56 engages its respective follower roller swinging the levers 73, 4 2, and 5 4. 'I husthefemale die 68 is swung toward the male die 67 and cuts a. window 14 in the vstrip 18 and; asthe female :die is retracted bythe 'sprin`g`75,",tl`1"e cam 86 actuates the valve 85 to permit compressed air to flow through the jetV orifices 82 'and eject the cutot portion 79. While one window is being cut out, the shoes 91 seal the strip 18 to the transparent strip 59 around another window which had previously been cnt and advanced to the station 60 and tle shoe v'40, being o n .the same lever 42 as the shoes 91, swings' for- Ward with the latter and cross-seals the three strips between the window ,being sealedy and the window which was sealed during the previous cycle'. At the Sametime, the blades 52 and 53 cut the window sheet 15 from the transparent "strip rand sever the bag 10 at the leading end of the strips. After these o'pe'rations" have been coinpleted; the yindexing mechanismv `33 again is effective to turn' the feed rollers 29 and 30 and advance the three strips vthrough a' distance e'qualo th'e width of the' bags and, during a subsequent dwell of the strips; the above operations are repeated.

. ItY will be seen that a standard bag making Vmachine has been adapted to cut the windows 14 in the bags 10; 'cut the window sheets .15 to the proper size, position the sheet accurately with respect to vthe Window and seal the sheet `to 'the wall 1'1 around the window by the addition of only three vsimple mechanisms, namely, the shaft 62 and its support for mounting the roll 61 of transparent strip mat'eial 59,1l thepunchingv mechanism 66 and the sealing elements 87 and. 88. B`y usingthe feed rollers 29 and 30 and the knife blades 52 and 53 which advance and cut the strips 18 and 19 to -feed and cut the transparent strip V59, the transparent window sheet 15 is positionedautomatically. with respect t'o the bag walls V11 and 12. This synchronized movement of the strips achieves `a lhigh degree of accuracy and; as a result; 'the transparent sheet is always 'centered Vrelative to the 'vvindow V14V so' that ,the bags 10 are Vneatand well formed. In' addition,` such accuracy visobtained without the use of special synchronizing mechanisms by. utiliiing vthe mechanisms already present in the standard maehine.

I claim as my invention:

1. A bag making machine comprising, means for supporting a rst strip of material and guiding the same endwis'e along a predetermined path, mechanism for supporting a transparent strip alongside said iirst strip, means disposed along said path andoperable to fold said rst strip longitudinally around said transparent strip, rollers disposed in said path beyond said vfolding meansv and en# gageable with opposite sides of said folding stiip; an actuating mechanism for turning 'said 'rollers periodi; cally to advance said folded strip in succes's'ii'l'eV steps through distances corresponding to the width of the bags to be formed, V sealing 'elements disposed along-said path and engageable during dwelling of said strips the opposite sides of said folded strip to Vseal the saine 'to said transparent strip transversely of 'the strips, iriearsin` Cluding a cutter disposed along said path and operable during a dwell of the 'strips to cut a window in onfy de of said folded strip, ad "sealing members beyond id cutter anden'gageable with said one side and said trnsparent strip tose'althe same together aroundfthe window.

2. Apparatus for making bags from two' outside4 n strips and an intermediate transparent strip, 4saidappiatratiis having, in combination, mechanism 'for supporting the three strips of material side by side and Vadvent'ing the same endwise along a predetermined path through distances corresponding to the width of the bags to be formed, means including a cutter disposed along f path and operable tocut a window in one of the outside strips during dwelling of the strips, sealing elements disposed along said pathbeyond said cutter and engage'- able with said transparent Astrip and said one outside strip to seal the two strips Vtogether about the windvv, sealing members disposed, beyond sad @ne an agresse with said outside strips to seal thesame to said middle strip transversely of the strips and ybetween said windows thereby to form a bag, and a second cutter disposed along said path and beyond said sealing members and operable to cut said strips intermediate the edges of the transverse seal.

3. Apparatus for making bags from two outside wall strips and an intermediate transparent strip, said apparatus having, in combination, mechanism for supporting the three strips of material side by side and advancing the same endwise along a predetermined path through distances corresponding to the Width of the bags to be formed, means including a cutter disposed along said path and operable to cut a window in one of the outside strips during dwelling of the strips, sealing elements disposed along said path beyond said cutter and engageable with said transparent strip and said one outside strip to seal the two strips together about the window, and sealing members disposed beyond said cutter and engageable with said outside strips to seal the same to said middle strip transversely of the strips and between said windows thereby to form a bag.

4. In a bag making apparatus, the combination of, means for supporting a rst strip of material and guiding the same endwise along a predetermined path, means disposed in said path and operable to fold said strip longitudinally, rollers disposed in said path beyond said folding means and engageable with opposite sides of said -folded strip, an actuating mechanism for turning said rollers periodically to advance said strip in successive steps through distances corresponding to the width of bags to be formed, means including a cutter disposed along said path and movable into engagement with said strip to cut a window in the same, means for guiding a strip of transparent material endwise along said path and over said windows, sealing elements disposed along said path and engageable with the opposite sides of said rst strip to seal the same and said transparent strip together between said windows whereby said rollers advance said transparent strip with said first strip, and sealing members beyond said cutter and engageable with both of said strips to seal the same together around said windows.

5. In a bag making machine having a plurality of stations successively disposed along a predetermined path, the combination of, a die member disposed at one of said stations and projecting into said path, a sealing member projecting into said path at a subsequent station, mechanism for supporting and advancing two strips of outside wall material and an intermediate transparent strip side by by side through successive steps along said path with a rst outside strip passing in front of said members, the second outside strip passing behind said members and the middle strip passing behind said die member and in front of said sealing member, a complemental die disposed in front of said die member and movable into engagement with the same to cut a window in said first outside strip, a sealing element disposed in front of said member and movable into engagement with said first outside strip to press the same and said middle strip against the member' and seal the strips together around said window, and means to move said die and said sealing element during dwelling of said strips.

6. Bag making apparatus having, in combination, means for supporting two strips of outside wall material and an intermediate transparent strip side by side and advancing the same endwise in successive steps along a predetermined path, means including a cutter disposed along said path and operable during a dwell of the strips to cut a window in one of the outer strips, a member disposed along said path beyond said cutter and projecting between the transparent strip and said one outer strip, said member having sealing surfaces facing said one outer strip and corresponding in size and shape to the edges of the one outer strip around the window, a sealing element disposed adjacent said member and on the outside of the other of said outer' strips and having a sealing surface facing the strips and extending transversely of the same, a sealing unit disposed on the outside of said one outer strip and movable toward and away from the strips, said unit having complemental sealing surfaces opposing the surfaces on said member and a sealing surface opposing and complementing the surface on said element, and means operable during dwelling of the strips to move said sealing unit against said strips to seal the three strips together transversely and to seal the one outer strip and the transparent strip together around a window.

7. In a bag making machine having stations successively disposed along a predetermined path, the combination of, mechanism for supporting two strips of outside wall material and an intermediate transparent strip side by side and advancing the same endwise along said path in successive steps, means including a cutter at one of said stations and operable during a dwell of said strips to cut a window in one of the outside strips, a sealing member disposed at a subsequent station and projecting into said path and between the other outside strip and said transparent strip, a sealing element disposed at said last mentioned station and movable toward the strips to press said one outside strip and said transparent strip against said sealing member and seal the two strips together around said window, and means operable during a dwell of the strips to move said sealing element toward said sealing member.

8. In a machine for making window bags, the combination of, means for supporting a first outside strip having windows formed therein at intervals of a predetermined distance, a second outside strip and an intermediate transparent strip in side by side relation, mechanism for advancing said strips endwise and intermittently through said predetermined distance, a member disposed along the path of said strips and projecting in between the other of said outside strips and said transparent strip, a second member disposed on the outside of said window strip and opposing said first member, said members having complemental sealing surfaces alined during dwelling of the strips with the edges of said windows, and means operable during dwelling of the strips to move said members together thereby to press said window strip and said transparent strip between said sealing surfaces and seal the two strips together around the window.

9. In a bag making machine having stations successively disposed along a predetermined path, the combination of, mechanism for supporting two strips of outside wall material and an intermediate transparent strip side by side and advancing the same endwise in successive steps along said path, a stationary member disposed at one of said stations and projecting between the transparent strip and one of the outer strips, a die bodily supported on said member and having cutting surfaces facing said one outer strip, a movable die disposed at said one station and having cutting surfaces opposing and complementing the surfaces on the stationary die, means operable during dwelling of the strips to move said movable die toward said stationary die thereby to cut a window in said one outer strip, and sealing elements disposed at a subsequent station and engageable with the outer strips between the windows to seal the outer strips to the transparent strip thereby to form bags.

l0. In a bag making machine having stations successively disposed along a predetermined path, the combination of, means for supporting two strips of material side by side, mechanism for advancing said strips endwise along said path step by step through distances corresponding to the width of the bags to be formed, a member disposed at one of said stations and projecting between said strips, a die bodily supported on said member and having cutting surfaces facing one of said strips, a movable die disposed at said one station and having cutting surfaces opposing and complementing the surfaces of the die on said member, means operable during dwelling of the' strips to move said movable die toward said other die thereby to cut a portion out of said one strip, and sealing elements disposed at a station subsequent to said first station and engageable with said strips to seal the same together transversely thereby to form 6 10 Grant et al Feb. 18, 1936 Flynn et al. May 17, 1938 Moore May 20, 1941 Robinson Feb. 10, 1942 Stevens et al. June 13, 1950

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