MXPA98000739A - Zip closure strap and the method of placement of the longitudinal axis, transverse of the t - Google Patents

Abstract

The present invention relates to a method for manufacturing bags with closure in an automatic packaging machine of flexible material, wherein the method comprises the steps of: providing a sheet of thermoplastic sheet material having at its length and at regular intervals a stretch of strip of zipper fastener transversely attached to the center of this and having strips without zip fastener strips on two side edges, where the zip fastener stripe has male and female interlocking profiles, where one between the male and female interlocking profiles have a lattice wider than the other on at least one of its two lateral sides, where the largest width of the widest lattice is at least one flank that runs along, where one of the interlocking male and female profiles that has the widest lattice is attached to the blade, and the other of the interlocking male and female profiles is not in contact with the blade, and at least u n flank oriented in a direction of movement of the sheet on the horizontal machine automatic packaging of flexible material, where at least one flank is sealed to the sheet to join together the male and female interlacing profiles, provide a product conveyor to deposit a product To be packed in the sheet of thermoplastic sheet material, fold the two side edges of the sheet of thermoplastic sheet material towards each other and around the product, seal the two side edges of the sheet with each other to form a wrapping tube the product, seal the tube transversely with respect to the section of the zip fastener strip without sealing together the trusses of the male and female interlacing profiles, and cutting the sealed tube to separate each completed package from the following

Description

Zip fastener strip and method of positioning the longitudinal axis, transversal strip Cross reference of related applications This is a partial continuation (CIP) of the Application for the United States patent with serial number: 08 / 651,977 registered on May 21, 1996.

Background of the Invention 1. Field of the Invention The present invention relates to reclosable plastic bags of the type in which they are packaged for sale to the consumer of perishable food products and other goods, in retail stores. retail More specifically, the present invention relates to elaborately resealable plastic bags which are filled concurrently in forming, filling and sealing machines (FFS), horizontally or vertically, where an interconnecting zipper closure, plastic it is arranged transversely, in relation to the direction of movement of the sheet of thermoplastic material used to form the reclosable bags in the FFS machine. 2. DESCRIPTION OF THE PRIOR ART The present invention relates to improving the technique for making packaging and can be practiced in the production of thermoplastic bags and packaging of the kind that can be used for various consumer products, but which are particularly useful for food products that must be kept moist and in vacuum packaging, without leaking liquid until it is opened for the first time, to have access to the contained products, then these packages are closed again by zipper to protect any quantity of product without consuming yet. The indicated technique develops really well, but, nevertheless, it is still susceptible of improvements that contribute to increase the efficiency and cost effectiveness. A problem that still prevents the production of continuous sheet material packages equipped with a slide fastener is the difficulty to achieve a satisfactory seal of the bag or packaging that does not allow any type of leak, where the zipper and the zipper The film is joined by means of the closure that extends through the lateral areas of the (transverse) seal that separate one bag or package from the next. This problem occurs when the slide fastener is longitudinal with respect to the direction of movement of the sheet of thermoplastic material that is used to form the reclosable bags in the FFS machine, in which case the bar is sealed laterally or transverse they should be flattened and sealed from the zip fastener, while sealing the sheet of thermoplastic material from which the gaskets are made, the difficulty with which this is consistently and successfully achieved is reflected in the high occurrence of leaking gaskets. Numerous attempts have been made to solve this problem. Among the approaches that have been made is the replacement of the transverse zipper closure by a longitudinal slide fastener. When this slide fastener is provided, the transverse seal bars associated with the FFS machine do not flatten the slide fastener, while making or forming the side seal, although these bars can seal the slide fastener on the sheet of thermoplastic material transversely. without flattening them The present invention relates to the provision of a transverse zipper closure for re-closing plastic bags or packages, which are manufactured either in horizontal or vertical machines. More specifically, the present invention is directed both to the zip fastener strip and to the method for securing the zip fastener strip transversely on the sheet of thermoplastic material from which the reclosable bags are made on an FFS machine.

Summary of the Invention According to the above, the present invention features a zip fastener strip for a resealable bag or package, which is manufactured and filled using a machine that forms, fills and seals. In particular, the zip fastener strip is designed to be positioned transverse to the movement through the machine of the laminated thermoplastic material that is used to form the packages. The laminated thermoplastic material comprises a male interconnection profile, having a male interconnecting member and a male band co-extruded therein.; and a female interconnection profile and a female coextruded band therein. The male interconnect member engages under instantaneous pressure within the female interconnect member to join the male and female interconnection profiles. One of the male and female bands is wider than the other male and female bands in at least one of the two directions from the male and female interconnection members in the closed fastener strip. The greater amplitude of the width of the male and female bands means that it has a flange that extends beyond the other band on one and possibly on both sides. The zip fastener, as a consequence, can be joined transversely in the laminated thermoplastic material by sealing the flange of the male and female band or the flanges therein without sealing the male and female bands together. The present invention also comprises a method for joining this slide fastener transversely in the laminated thermoplastic material during the production of plastic bags or packages in the FFS machine. In this situation, a length of the slide fastener is attached to the laminated thermoplastic material, each time it is put to rest as it advances (increased or continuous) in or towards the FFS machine. This method includes the step of providing a slide fastener of the variety described above. The length of the zip fastener strip is then arranged transversely in the laminated thermoplastic material, with the widest part of the male and female bands in contact with the sheet and with the flange, or the flange if there is only one , oriented in the direction of the movement of the sheet. Then, the flange or flanges seal the sheet without sealing the male and female bands together. Next, various specific ways of arranging the length of the slide fastener in the laminated thermoplastic material will be described. Finally, the present invention comprises a method for manufacturing reclosable gaskets in a form, fill and seal machine. The method includes the step of providing a laminated thermoplastic material having a length of zip fastener strip attached thereto at regularly spaced intervals, as described above. Then, the conveyor belt of the product deposits it, at regularly separated intervals, to be packed in the laminated thermoplastic material. Then, the two lateral edges of the sheet are bent towards each other and around the product, and sealed with one another to form a tube that encloses the product. Then, the tube is sealed transversely on each length of the slide fastener without the bands of male and female interconnecting profiles sealing against each other. Then, the tube is cut transversely, adjacent to each length of the slide fastener to separate each completed package from the next. The present invention will now be described in more complete detail, frequently referring to the figures identified below.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view of a first embodiment of the slide fastener of the present invention; Figure 2 is a cross-sectional view of a second embodiment of the slide fastener; Figure 3 is a perspective view of an apparatus that is used to attach the slide fastener to the laminated thermoplastic material; Figure 4 is a perspective view of an alternative apparatus that is used for this purpose; Figure 5 is a perspective view of another apparatus that is used for this purpose; Figure 6 is a schematic view of a horizontal FFS machine; Figure 7 is a plan view of a laminated thermoplastic material, with zip fastener lengths attached thereto, which is used to produce the packages in the horizontal FFS machine; and Figure 8 is an enlarged cross-sectional view of a package that is formed in a horizontal FFS machine in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specifically, with reference to the Figures identified above, Figure 1 is a cross-sectional view of a first embodiment of the zipper strip 10 of the present invention. The zipper strip 10 comprises a male interconnecting profile 12 and a female interconnection profile 14. The male interconnecting profile 12 includes a male interconnecting member 16 which may have an arrow-shaped cross section or, as shown in Figure 1, a cross-section in the shape of an arrowhead, designed to make the slide fastener open more easily from one side than the other. The female interconnection profile 14 includes a female interconnect member 18 comprising two inwardly curved members that form a receptacle or channel in which the interconnecting member strands 16 can be snapped under instantaneous pressure. Both the male and the female interconnection profile 12, 14 include co-extruded bands with the male and female interconnection members 16, 18. It can be seen that the band 20 of the male interconnection profile 12 is wider than the band 22 of the profile of female interconnection 14. As a consequence of the above, the band 20 has a guide flange 24 and a drag flange 26, which together make the amount by which the band 20 is wider than the band 22. As will be clear then, the guide and drag flanges 24, 26 are so named since, when the strip of the slide fastener 10 is joined to the laminated thermoplastic material that is fed into the FFS machine, the guide flange 24"guide" the strip of the cross-linked zipper closure 10 towards the machine, and the dragging flange 26"pulls". Finally, the guide flange 24 resides on the inside of the mouths of the bags or plastic packaging that are manufactured and concurrently filled with the consumer product in the FFS machine. While the male interconnection profile 12 shown has both the guide and drag flanges 24, 26, in return, both flanges 24, 26 could, alternatively, be part of a female interconnection profile 14. The closure strip of rack 10 is transversely disposed in the laminated thermoplastic material during the manufacture of plastic bags or packages in an FFS machine. The zipper strip 10 is placed with the male and female interconnection profiles 12, 14 attached as shown in Figure 1, in the laminated thermoplastic material with the male interconnection profile 12 resting thereon. The heat seal bars 28 or the like, applied against the guide and drag flanges 24, 26, as suggested by the arrows in Figure 1, seal the male interconnection profile 12 to the laminated thermoplastic material (which is not sample) without sealing the band 22 of the male interconnection profile 12. The heat sealing materials 30 can be applied on the outside of the band 20 of the male interconnection profile 12, including the outer sides of the guide and drag flanges 24, 26, as well as the inner side of the drive flange 26 and on the outer side of the band 22 of the female interconnection profile 14, to facilitate sealing Laminated thermoplastic material. The drag flange 26 can also be separated from the rest of the band 20 by perforations. The outer sides of the guide and drag flanges 24, 26 are joined to the laminated thermoplastic material before the sheet of material reaches the shoulder in the vertical FFS machine, or before the sheet of material enters the FFS machine. Then, when the sheet of material is bent to form a tube with the side edges sealed on a tongue or with an overlap seal, the laminate is sealed to the inner parts of the drive flange 26, as well as to the outer sides of both bands 20, 22 without sealing the portions towards the strips 20, 22 together. Figure 2 is a cross-sectional view of an embodiment of a slide fastener strip 40 of the present invention. The common elements both for the zipper strip 40 and for the zipper strip 10 were described above, and indented in Figure 2, with the use of the same reference numbers. A comparison between Figure 1 and Figure 2 indicates that the zipper strip 40 lacks a drag flange 26, but is identical to the zipper strip 10 in all other respects. As with the zipper strip 10, the zipper strip 40 is transversely disposed on the laminated thermoplastic material during manufacture of the plastic bags or packages in the FFS machine. The male interconnection profile 42 lies in the laminated thermoplastic material. The heat sealing rods 28 or the like, are applied to the guide flange 24, indicated by the arrows in Figure 2, seal the male interconnection profile 24 in the laminated thermoplastic material (not shown) without sealing the band 22 of the female interconnection profile 14 with the band 44 of the male interconnection profile 42. As before, while the male interconnection profile 42, shown, has a guide flange 24, in turn, the guide flange 24 may alternatively be , part of a female interconnection profile 14. Both the zipper strips 10 and 40 shown in Figures 1 and 2, respectively, can be extruded from a polymeric resin material, such as for example low density polyethylene ( LDPE). The heat sealing materials 30 can be applied, as shown, by co-extrusion or by coating followed by extrusion of the zip fastener strips 10, 40. Ethylene vinyl acetate (EVA) copolymers can be used as materials heat seal 30. Figure 3 is a perspective view of an apparatus that is used to attach the zipper strip 10 to the laminated thermoplastic material 50, which moves in the direction of the arrows therein towards the machine. FFS. The laminated thermoplastic material 50 moves intermittently in increments equal to the length of the lengths of the packages that are produced. Each time the laminated thermoplastic material 50 is allowed to rest, a length of the zip fastener strip 10 is sealed transversely to the length of the front upward side thereof. The tape of the slide fastener 10 is provided from a roll or other form of supply that is not shown in Figure 3, and is fed through a stationary clamp 52, and through a reciprocating trigger 54, which includes the clamp 56. and a guillotine 58, the latter is used to cut the strip 10 when required.

The trigger 54 alternates each time the laminated thermoplastic material 50 momentarily stops. When the trigger 54 moves outwardly above the laminated thermoplastic material 50, the clamp 56 closes on the tape of the slide fastener 10, while the stationary clamp 52 is opened, such that the trigger 54 pushes a length of tape of the zipper closure 10 from the roll. The outer end of the trigger 54 is a probe 60, which allows the guide flange 24 and the drive flange 26 of the zip fastener tape 10 to protrude from the sides thereof. As shown in Figure 3, the trigger 54 is in its retracted position. When in its forward position, which is not shown, the probe 60 extends into the space between the upper sealing jaw 62 and its corresponding lower sealing jaw 64, the latter being on the underside of the laminated thermoplastic material 50. The guide and drag flanges 24, 26 extend outwardly between the upper and lower jaws 62, 64. When the jaws 62, 64 are closed, the bars 28 seal the flanges 24, 26 in the laminated thermoplastic material 50. Then, the jaws 62, 64 open; the guillotine 58 cuts the next length of the zipper strip 10; the clamp 56 opens and the clamp 52 closes. Then, the trigger 54 retracts towards the position shown in Figure 3, while the laminated thermoplastic material 50 moves a length equal to the length of the package being manufactured to repeat the process. Figure 4 is a perspective view of an alternative apparatus that is used to attach the zipper strip 10 to the laminated thermoplastic material 50. As before, the laminated thermoplastic material 50 is transported in the direction of the arrow to the FFS machine. , and it moves intermittently in an increment equal to the length of the package length that is manufactured. Again, each time the laminated thermoplastic material 50 is momentarily stopped, the length of the zipper strip 10 is transversely sealed along the side of the top face thereof. The zipper strip 10 is dispensed from a roll or other supply that is not shown in Figure 4, which is pulled by means of a first clamp 70, which alternates back and forth along the mechanism 74 in the passage with a second clamp 72. The first and second clamp 70, 72 grip the guide flange 24 of the zipper strip 10 to pull the zipper strip 10 transversely along the laminated thermoplastic material. The second clamp 72 secures the zip fastener strip 10 in position, while sealing to the upper side of the laminated thermoplastic material 50. A stationary guillotine 76 is used to cut the fastener strip 10 when required. Each time the laminated thermoplastic material 50 is momentarily stopped, the second clamp 72 provides the length of the strip of the slide fastener 10, which is cut by means of the stationary guillotine 76, transverse to the outside thereof, in the position shown in Figure 4. At the same time, the first clamp 70 moves in the passage with a second clamp 72, a length of the strip of the slide fastener 10 is moved through the guillotine 76. the upper sealing jaw 62 and its corresponding lower jaw 64, the latter located on the lower side of the laminated thermoplastic material 50, seals the guide flange 24 and the drive flange 26 of the zipper strip 10, while the second clamp 72 holds the guide flange 24. Then, the first clamp 70 and the second clamp 72 are retracted from the positions shown in Figure 4, the first clamp 70 is retracted e to a position adjacent to the guillotine 76, and the second clamp 72 retracts upwards from the guillotine 76 along the zipper strip 10. Then, the laminated thermoplastic material 50 moves a length equal to the length of the package being manufactured to repeat the process. Figure 5 is a perspective view of another apparatus that is used to join the strip of the slide fastener 10 with the laminated thermoplastic material 50. The laminated thermoplastic material 50 is transported in the direction of the arrow to the FFS machine and, as previously, it moves intermittently in an increment equal to the length of the length of the package being manufactured. Again, each time the laminated thermoplastic material 50 is momentarily stopped, the length of the zipper strip 10 is sealed, transversely, along the upper side thereof. The zipper strip 10 is provided from a roll or other supply, which is not shown in Figure 5, which is pulled from it by means of a perforated belt 80 placed between the chambers 82, 84, joined by vacuum or suction. The suction through the perforated belt 80 is used to transport the zipper strip 10. The stationary guillotine 85, through which the strip of the slide fastener 10 passes, is used to cut the strip of the slide fastener 10. when it is required Each time the laminated thermoplastic material 50 is momentarily stopped, the perforated belt 80 provides a length of the strip of the slide fastener 10 transversely, along the laminated thermoplastic material 50. The guide flange 24 and the drive flange 26 of the the zipper 10 pulls extend beyond the two sides of the perforated belt 80 and the chamber 82, which extends into the space between the upper sealing jaw 62 and its corresponding lower sealing jaw, the latter being on the underside of the laminated thermoplastic material 50. The guide and drag flanges 24, 26 extend outward from the upper and lower sealing jaws 62, 64. The vacuum is turned off. When the jaws 62, 64 close, the heat sealing bars 28 seal the flanges 24, 26 in the laminated thermoplastic material. The jaws 62, 64 then open, and the laminated thermoplastic material 50 moves a length equal to the length of the package being manufactured. Then, the vacuum goes on; the guillotine 86 cuts the strip of the zipper closure 10; and the perforated belt 80 drives the portion of the zipper strip 10 transversely along the laminated thermoplastic material 50 to repeat the process. Any of the above apparatus for attaching the zipper strip 10 with the laminated thermoplastic material 50 can be used in the manufacture of the packages in a horizontal or vertical FFS machine. In this sense, Figure 6 is a schematic view of a horizontal apparatus. A roll 90 of a laminated thermoplastic material 50 provides the sheet 50 intermittently at a length equal to that of the packages being manufactured and filled. A length of the zip fastener strip 10 is applied by means of an applicator of the slide fastener 92, which can include any of the described apparatuses, in the center of the laminated thermoplastic material 50, as shown in Figure 7, leaving sufficient material along the side edges 96 of the laminated thermoplastic material 50 to be bent towards one another and thus joined in a tongue overlap or seam. The accumulator 94 is used to convert the intermittent movement of the laminated thermoplastic material 50 into a continuous movement. A product conveyor 98 carries the product 99 to be packaged towards the wrapping machine 100, which comprises a forming area 102, a sealing area 104 and a transverse sealing area 106. In the forming area 102, the two side edges 96 of the laminated thermoplastic material 50 are folded up and around the product. In the sealing area 104, the two side edges 96 are sealed against each other with a tongue seal to form a continuous tube of film with the product and the zipper strips 10 inside. In the transverse sealing area, the bands of the zipper strip 10 are sealed with the laminated thermoplastic material 50, without sealing the bands together, and the packages separate from one another along the lines 112, and they are carried forward by means of the conveyor belt 108. Figure 8 presents 110 formed in accordance with the above and contains the product 99 itself. In this package the upper (wide) flange 26 of one of the profiles is sealed with the portions of the film web forming the lower part of the pack 114 as well as the upper part of the pack 116. The other wide flange 24 of this profile is secured to the portions of the web of the film forming the lower part of the pack 114 while the narrow flange 22 of the other profile is only secured to the portions of the band of the film forming the upper part of the package 116. Modifications to the above will be obvious to those skilled in the art. ca, but do not provide an invention so modified that it falls outside the scope of the appended claims.

Claims (10)

Claims

1. A zip fastener strip for reclosing gaskets or bags, this fastener strip comprises: a male interconnect profile, and this male interconnect profile has a male interconnect member protruding therefrom; and a female interconnection profile, this female interconnection profile has a female interconnecting member and a female band that co-extrudes therein, the male interconnecting member is snapped under instantaneous pressure within the female interconnecting member to join these interconnection profiles male and female, wherein one of the male and female bands is wider than the other of the male and female bands in at least one of the directions from the male and female interconnecting members, the largest amplitude of the widest of the male and female bands are at least one flange extending, widthwise, beyond the other of the male and female bands, such that the strip of the slide fastener can be attached to the laminated thermoplastic material which is sealed to the less to a flange thereof without sealing the male and female bands together.

2. The zip fastener strip according to claim 1, wherein one of the male and female bands is wider than the other of the male and female bands only in one of the two directions from the male and female interconnection members, The greater amplitude of the width of the male and female bands are flanges that extends beyond the other of the male and female bands in one of the two directions.

3. The zip fastener strip according to claim 1, wherein one of the male and female bands is wider than the other of the male and female bands in both directions from the male and female interconnecting members, the The greater amplitude of the width of the male and female bands are the two flanges that extend beyond the other of the male and female bands in opposite directions from the male and female interconnecting members.

4. The method of joining the zip fastener strip transversely into the laminated thermoplastic material during the production of plastic bags or packages having transverse zip fasteners in a machine for forming, filling and sealing, the sheet moving in a length equal to that of the bags and packages being manufactured, the length of the zip fastener strip is attached each time the sheet is stopped, this method comprises the steps of: providing a zip fastener strip having male and female interconnection profiles, one of the male and female profiles has a band wider than the other on at least one of the two lateral sides thereof, the greater amplitude of the wider band is in at least one flange a throughout it; arranging a length of the strip of the slide fastener transversely in the laminated thermoplastic material, one of these male and female interconnection profiles has a wider band that is in contact with the sheet and at least one of the flanges is oriented in the direction of movement of the leaf; and sealing at least one of the flanges in the laminated thermoplastic material without sealing the bands of the male and female profiles together.

The method according to claim 4, in which one of the male and female interconnection profiles has a band wider than the other on the two lateral sides thereof, the greater amplitude of the wider band is a flange It runs along each lateral side of it.

6. The method according to claim 4, wherein the step of disposing the length of the strip of the slide fastener transversely in the laminated thermoplastic material is carried out by means of a reciprocating trigger having a clamp and a guillotine , this clamp is provided for pulling the zip fastener strip from a transverse supply in the sheet and the guillotine is provided for cutting the length of the fastener strip.

7. The method according to claim 4, in which the step of arranging the length of the zip fastener strip transversely in the laminated thermoplastic material is carried out by means of a pair of reciprocal clamps separated by a stationary guillotine, both reciprocal clamps grip the strip of the zip fastener by means of at least one of the flanges thereon, one of the alternating clamps transfers the length of the zipper strip cut by the guillotine on the sheet of the laminated thermoplastic material and fastens the length during the step of sealing, and the other of the alternating clamps pull the zip fastener strip from a supply thereof to the guillotine.

The method according to claim 4, wherein the step of arranging the length of the zipper strip transversely in the laminated thermoplastic material is carried out by means of a vacuum converter and a guillotine, the mechanisms of the vacuum converter pull the zip fastener strip from the fastener supply and pull the lengths cut by the guillotine into the laminated thermoplastic material.

9. The method according to claim 4, wherein the movement of the sheet is increased.

10. The method for the manufacture of resealable packages in a machine for forming, filling and sealing, horizontal, this method comprises the steps of: providing a laminated thermoplastic material having regular intervals over the entire length of the strip of zip fastener joined transversely along the center thereof and having strips without a zip fastener strip on the two side edges thereof, the zip fastener strip having male and female interconnection profiles, one of these male and female interconnection profiles have a band wider than the other on at least one of the side sides of the mass, the greater amplitude of the wider band is at least one flange running the entire length, one of the Male and female profiles have a wider band that joins the sheet, the less one of the flanges is oriented in the direction of the movement of the sheet on the machine to form, fill and seal horizontal, at least one of the flanges is sealed on the sheet to join the male and female interconnection profiles therein; providing a product conveyor that deposits the product to be packaged in the laminated thermoplastic sheet; folding the two side edges of the laminated thermoplastic sheet towards each other and around the product; sealing the two lateral edges of the sheet with one another to form a tube that encloses the product itself; sealing the tube transversely in each of the lengths of the zipper strip without sealing the bands of the male and female profiles together; and cut the sealed tube to separate each complete package from the next.