US3355996A

US3355996A - Bag making machine

Info

Publication number: US3355996A
Application number: US467299A
Authority: US
Inventors: William R Medleycott; Robert F Nowalk
Original assignee: Superpac Inc
Current assignee: Superpac Inc
Priority date: 1965-06-28
Filing date: 1965-06-28
Publication date: 1967-12-05
Anticipated expiration: 1984-12-05

Description

1957 w. R. MEDLEYCOTT ETAL 3,355,995

BAG MAKING MACHINE Filed June 28, 1965 5 Sheets-Sheet 1 no F 3 D60 1967' w. R. MEDLEYCOTT ETAL 3,355,996

BAG MAKING MACHINE 5 Sheets-Sheet 2 Filed June 28, 1965 MMMA ATTORNEYS Dec. 5, 1967 W. R. MEDLEYCOTT ETAL BAG MAKING MACHINE Filed June 28, 1965 5 Sheets-Sheet 5 +6 INVENTORS FIG. 5.

WILLIAM R. MEDLEYCOTT 8 BY ROBERT F. NOWALK ATTORNEYS Dec. 5, 1967 Filed June 28, 1965 FIG. 9v

w. R. MEDLEYCOTT ETAL 3,355,996

BAG MAKING MACHINE 5 Sheets-Sheet 4 INVENTORS WILLIAM R. MEDLEYCOTT 8x BY ROBERT F. NOWALK ATTORNEYS Dec. 5, 1967 w. R. MEDLEYCOTT ETAL 3,

BAG MAKING MACHINE Filed June 28, 1965 5 Sheets-Sheet 5 I6 26 24 I j t g d 1 ll L20 ll 2e fee F l 6. IO.

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1 1 l Z ---r:-

FIG. ll.

INVENTORS WILLIAM R. MEDLEYCOTT 8 BY ROBERT E NOWALK ATTOR N EYS United States Patent Ofitice 3,355,996 Patented Dec. 5, 1967 3,355,996 BAG MAKING MACHINE William R. Medleycott, Willingboro, N.J., and Robert F.

Nowalk, Hatboro, Pa., assignors to Superpac, Inc, Warrington, Pa., a corporation of Pennsylvania Filed June 28, 1965, Ser. No. 467,299 2 Claims. (Cl. 93-8) ABSTRACT OF THE DISCLOSURE Doubled-over thermoplastic material forming a web having a fold line is fed past a perforator to form an easy-tear opening strip. Gusseting wheels receive the web and move the fold line inwardly to form inner and outer panels. Heat-sealing means seal the inner panels to the outer panels to form a gusset. Cutter-sealer means cut transversely across the web to form edges of a side of a bag and seal the side edges.

This invention relates to a bag making machine and more particularly relates to a machine for making bags of thermoplastic material having a pair of outer panels sealed at the side edges, a double-thickness handle at the top formed of outer and inner panels with the inner panels sealed to the outer panels along seal lines at the bottom of the handle, and a gusset extending between the seal lines to form a top panel for the bag.

The primary object of the invention is to provide a bag having an integral handle and capable of containing relatively thick articles such as, for example, paper towel rolls or food cans.

Another object is to provide a bag making machine with gusset sealing means which does not burn the Web being processed into a bag even though a station of the machine is operated intermittently.

The inventions and its objectives will be understood from a reading of the following description in conjunction with the drawings in which:

FIGURE 1 is a view in elevation, partly schematic and partly in section, of a machine in accordance with the invention;

FIGURE 2 is a top plan view of the machine of FIG- URE 1;

FIGURE 3 is a partial view on an enlarged scale of a portion of the top plan view of FIGURE 2;

FIGURE 4 is a side elevation, partly in section, of the apparatus shown in FIGURE 3;

FIGURE 5 is a vertical section of the machine taken along the plane indicated by the lines 5-5 in FIGURE 2;

FIGURE 6 is a vertical section taken along the planes indicated by the lines 6-6 in FIGURE 5;

FIGURE 7 is a fragmentary side view of apparatus which isconne-cted to the apparatus of FIGURE 6;

FIGURE 8 is an end view of the apparatus of FIG- URE 7;

FIGURE 9 is a side elevation, partly in section, of perforator apparatus which forms an element of the invention;

FIGURE 10 is a view in elevation of a bag formed by the machine; and

FIGURE 11 is a horizontal section of the bag taken along the'plane indicated by the lines 11-11 in FIG- URE 10.

,Referring first to FIGURE 1, a bag making machine in accordance with the invention has a sealing station 2 which is provided with means for continuously forming a gusset in a web 4 and sealing the ends of the gusset, and a cut-off station 6 which is provided with means for intermittently cutting transversely across web 4 to form edges of a side of a bag and seal the side edges. A compensator 8 is positioned between sealing station 2 and cut-ofl? station 6 and is provided with means for compcnsating for the intermittent action of cut-off station 6 so that the web 4 remains taut throughout its passage through the machine.

Referring now to FIGURES 10 and 11, a bag 10, made of thermoplastic material such as polyethylene or polypropylene, is produced by the machine and comprises outer panels 12 joined to inner panels 14 along fold lines 16, with the inner panels 14 being joined together along an inner fold line 18.

Each inner panel 14 is sealed to its associated outer panel 12 along a seal line 20 in such a fashion that a gusset 22 is formed between the seal lines 20 and accordingly extends between outer panels 12. The upper portion of inner panels 14 and outer panels 12, above seal lines 20, form a handle 24 of double thickness and have a hand hole 26 formed therein.

Side edges 28 of bag 10 are sealed together and bottom 30 of the bag is open when delivered from cut-01f station 6, and is adapted to be sealed closed after being loaded with three rolls of paper hand towels 31 as shown in FIGURE 10, or other material.

Gusset 22 is provided with parallel perforations 32 on each side of fold line 18 to form an easy-tear opening strip 34 having cross-perforations 35. Accordingly, bag 10 may be opened to remove its contents by punching a finger through cross-perforations 35 and pulling on easytear strip 34.

Referring to FIGURES 1 and 2, sealing station 2 includes a perforator 36 for perforating the inner part of what is to be gusset 22 in order to provide the opening strip 34.

The means for providing hand holes 26 in handle 24 are shown in cut-off station 6 and include a punch die 38 positioned above an anvil 40, and an air blower 42. Punch die 38 reciprocates to punch the outline of hand hole 26 in handle 24 when the web 4 is in position on anvil 40. Air blower 42 blows the tab formed by punch die 38 away from web 4 to leave hand hole 26.

A support frame 44 is provided for supporting the various rollers of the machine including a feed roll 46 of doubled over thermoplastic material which forms a web 4 having the fold line 18 which is folded inwardly by the machine. Web 4 is trained downwardly and horizontally over a series of

tension rollers

48, 50, 52, and 54, and then is trained upwardly to pass through perforator 36 which perforates the web near fold line 18 to form the easy-tear strip 34.

Proceeding horizontally from perforator 36, Web 4 comes in contact with a pair of gusseting wheels 56 which are mounted, as shown in FIGURES 3 and 4, on support frame 44 by a support 58. Gusset wheels 56 fold the line 18 inwardly into the opening between upper plate 59 and lower plate 61 of gusset bracket 63.

Rollers

60 and 62 are positioned above and below the web 4 at what is to become the bottom of the bag and are in contact with the web and serve to prevent creases or slack in the web which might be caused by the gusseting operation.

From

rollers

60 and 62, web 4 passes through a series of

tensioning rollers

64, 66, and 68 and then passes downwardly for the next operation, that of sealing the gusset.

The gusset sealer apparatus comprises a series of

spacer rollers

70, 72, 74, and 76, a first gusset sealer 78 which seals gusset 22 to one outer panel 12 along seal line 28, and a second gusset sealer 80 which seals the gusset 22 to the other outer panel 12.

After sealing, web 4 passes over a guide roller 82 to a roller 84 and a rubber nip roll 86 which is power 8 driven and pulls the web 4 from feed roll 46 in a continuous manner.

The side edges 28 of bag are cut and sealed in cutoff station 6 in a. conventional manner such as that illustrated. and described in US. Patent No. 2,947,345 which issued on Aug. 2, 1960, to G. T. Schjeldahl for a machine for making, articles. from multiple thermoplastic webs. Web 4 is drawn over rollers 88;, 90, 92 and take-up roller 94 by a pair of draw rolls 96 and delivered. to a cuttersealer knife 98. that is reciprocably positioned over abackup roll: 100 which is preferably a Teflon roller.

Compensator 8' keeps web 4 taut throughout its travel through the machine despite the. fact that the web is moved intermittently in cut-off station 6. andyet is moved continuously in sealing station 2. Compensator 8 includes.

a pivoted compensator arm 102 which is free at oneend 104 and is pivoted at the other end 106. A series of rollers 108 are mounted near free end 104,. and another series of rollers 110 are fixedly mounted and spaced. away from the arm rollers 108. A weight 112 is adjustably positioned on compensator arm 102.

Web 4 is threaded between arm rollers 108 and fixed rollers 110, and arm rollers 108 are moved with compensating, arm 102 away from fixed rollers 110 when web 4. has its movement stopped: in cut-off station 6,, thereby keeping the web taut. When movement of web 4 resumes in cut-off station 6, compensating arm 102 moves upward,- ly about its pivot and arm rollers 108 move closer to fixed rollers 11-0.

The .intermittent motion of web 4 in cut-off station 6 is controlled by an electronic eye 114. which is actuated by markings 116 that are spaced along web 4.

Gusset sealers

78 and 80 are similarly constructed and. the following description of sealer 78 applies equally well to sealer 80. Referring to FIGURES 3 and. 4, gusset sealer 78 includes an. electric heater unit 118 that contacts web 4 and is electrically connected to a heater control 120 which is pivotally connected, to a support 122 mounted on frame 44. An air-vacuum. ram 124. is operatively connected to an arm 126 extending from heater control 120. Ram 124 moves upwardly to move heating element 118. away from web 4- when the web isnot moving, and. thereby prevents heater element, 118 from burning through the web. Ram 124 is connected to an air line 14.8 having a solenoidoperated valve 150 connected to main switch 152, by an electrical conductor 154.

Referring to; FIGURES 58, compensator arm 1021's. moved downwardly about its pivoted end 106 by gravity, and is moved upwardly as web 4 is being pulled out of compensator 8 so that the shortened web in compensator 8 pulls rollers 108 toward rollers 110. An electric conductor 127 extends from master switch 152 to a variable speed motor 129 which drives nip roll 86. Another conductor 131 extends from motor 129 to a potentiometer 133. The position of compensator arm 102- determines the position. of a segment gear 135 and a split pinion. gear 137 mounted on one end of a shaft 139, and, thereby controls the speed of motor 129 and nip roll 86 to control the speed of web 4.

An arm 141 is mounted on the other end of shaft 139 and is driven by a link 143 which is connected to a bracket 146 mounted on compensator arm 102. Accordingly, in response to the position of compensator arm 102, link 143 moves arm 141 and rotates shaft 139 and segment gear 135 to rotate pinion gear 137 to adjust potentiometer 133 to change the speed of motor 129. When web 4 is stopped in cut-off station 6, compensator arm 102 is moved downwardly by the continuous feed of web 4 to compensator 8 and the distance between

rollers

108 and 110 is increased to take up any slack in the web and keep it taut. When web 4 is moving in cut-off station 6, compensator arm 102 moves upwardly by the speed of web 4 leaving compensator 8 and the distance between rollers 108. and 110 is decreased. This compensator 8 allows for fast movement of the web in cut-off station 6.

While the above description has outlined the operation of the essential parts of the machine, a brief summary of the operation may clarify its overall operation.

A feed roll 46of doubled-over thermoplastic material is mounted on support frame 44 and a web 4 of the material is trained over

rollers

48, 50, 52 and 54 and is passedthrough perforator 36 which perforates web 4 near its fold line 18 to form what isv to become an easy-tear open strip 34 of the bag 10.

Web 4 then passes through gusseting wheels 56 which fold the fold line 18.inwardly to form the inner panels 14 and outer panels 12.

Rollers

60 and 62 prevent creases from forming in the web during the gusseting operation. Then the web is trained

overrollers

64, 66, and 68 and passes downwardly to the

gusset sealers

78 and 80. The inner panels 14 are spread. apart by

rollers

70, 72, 74and 76, one of which is positioned on each side of the gusset sealers. The first gusset sealer 78 contacts and seals one outer panel 12 to its associated inner panel 14, and second gusset sealer contacts and seals the other outer panel to its associated. inner panel. Sealing. lines 20 are formed and the portion of the inner panels between the sealing lines forms a gusset 22. The upper portion of inner panels 14 forms a double thickness handle 24 with the upper portion of outer panels 12.

The web 4 is continuously drawn from feed roll 46- through perforator 36, gusseting wheels 56 and first and

second sealers

78 and 80 by a nip roll 86.

The Web 4 moving through cut-off station 6 is intermittently moved so that the cutting operation occurs when the web is stopped. Each side edge 28 of the bag 10 iscutand simultaneously sealed by the operation of cutter and sealer knife 98, and the web is intermittently drawn through, cut-off station 6 by draw'rolls 96. This intermittent motion of the web 4. is controlled by electronic eye.

114 which responds to markings 116 on web 4.

Also; at the cut-off station 6, punch die 38 cuts the outline of a hand hole 26 in the web, and air blower 42 blows the tab out of the hand hole.

compensator 8 compensates for the intermittent feed of the web 4. in the cutter-sealer station 6 so that the gusseting and gusset sealing may be accomplished in a continuous, fashion and keeps the web taut throughout its passage through the machine. Compensator 8 solves the serious problem of how to prevent gusset sealers78 and 80 from burning web 4. when the web is stopped in station 6.

It is to be understood that the form of the invention herewith shown and described is to be taken as a presently preferred embodiment, Various changes may be made in the shape, size and arrangement of parts. For example, equivalent elements may be substituted for those illustrated and described herein, parts may be reversed, and. certain features of the invention may be utilized independently of the use of other features, all without departing from the spirit or scope of the invention as defined in the subjoined claims.

What is claimed is:

1. 1n a machine for making bags of thermoplastic material, a gusset sealer for a web of said material having an inner fold line connecting together two inner panels and a pair of outer fold lines connecting the inner panels to outer panels, comprising a series of spacer rollers adapted to separate the inner panels, a first heater means adapted to contact the web and heat seal one inner panel to its associated, outer panel along a seal line without 5 6 sealing to the other inner panel, and a second heater References Cited. means adapted to contact the web and heat seal the other UNITED STATES PATENTS inner panel to its associated outer panel along a seal hne Without sealing to the first-said inner panel, whereby the $925,119 2/1960 Jaqlllfey inner panels form a gusset between the seal lines. 5 2,971,874 2/1961 C n 938 2. The machine in accordance with claim 1 having 3,146,147 8/1964 Naser 93-8 means for withdrawing the heater means from contact with the web when the web is not moving. GERALD A. DOST, Primary Examiner.

Claims

1. IN A MACHINE FOR MAKING BAGS OF THERMOPLASTIC MATERIAL, A GUSSET SEALER FOR A WEB OF SAID MATERIAL HAVING AN INNER FOLD LINE CONNECTING TOGETHER TWO INNER PANELS AND A PAIR OF OUTER FOLD LINES CONNECTING THE INNER PANELS TO OUTER PANESL, COMPRISING A SERIES OF SPACER ROLLERS ADAPTED TO SEPARATE THE INNER PANELS, A FIRST HEATER MEANS ADAPTED TO CONTACT THE WEB AND HEAT SEAL ONE INNER PANEL TO ITS ASSOAICTED OUTER PANEL ALONG A SEAL LINE WITHOUT SEALING TO THE OTHER INNER PANEL, AND A SECOND HEATER MEANS ADAPTED TO CONTACT THE WEB AND HEAT SEAL THE OTHER INNER PANEL TO ITS ASSOCIATED OUTER PANEL ALONG A SEAL LINE WITHOUT SEALING TO THE FIRST-SAID INNER PANEL, WHEREBY THE INNER PANELS FORM A GUSSET BETWEEN THE SEAL LINES.