Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B70/00—Making flexible containers, e.g. envelopes or bags
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B70/00—Making flexible containers, e.g. envelopes or bags
  • B31B70/26—Folding sheets, blanks or webs
  • B31B70/262—Folding sheets, blanks or webs involving longitudinally folding, i.e. along a line parallel to the direction of movement
  • B31B70/266—Folding sheets, blanks or webs involving longitudinally folding, i.e. along a line parallel to the direction of movement involving gusset-forming
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B2160/00—Shape of flexible containers
  • B31B2160/10—Shape of flexible containers rectangular and flat, i.e. without structural provision for thickness of contents
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B—MAKING CONTAINERS OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
  • B31B70/00—Making flexible containers, e.g. envelopes or bags
  • B31B70/74—Auxiliary operations
  • B31B70/86—Forming integral handles or mounting separate handles
  • B31B70/864—Mounting separate handles on bags, sheets or webs

Definitions

• the present invention relates to a process for manufacturing flexible plastic bags or possibly paper and, more specifically, so-called bellows bags.
• the invention also relates to a device for implementing this process as well as to the bags obtained by this process.
• the flexible plastic bags with bellows which are intended for the packaging and transport of various articles, for example clothing articles after their retail sale, are generally made from a sheath made of plastic which is scrolled in a flattened form and which is cut so as to form sheath sections whose lower opening is closed by welding and whose upper opening receives two rigid or semi-rigid bars internally provided each of a handle, the sheath being folded before cutting and welding, so as to form on the two edges parallel to the longitudinal direction of the sheath, each time a bellows intended to reduce the apparent width of the bag while giving it a capacity sufficient reception.
• the bars for their part, have an elongated longitudinal shape whose length corresponds substantially to the width of the folded bag with its bellows.
• the bars and possibly the handles that they carry, include means for mutual locking by snap-fastening allowing a closing and an opening of the bag.
• the manufacture of bars is carried out by plastic injection molding in a specially designed mold so as to be able to mold, at the same time, the two bars (with their handles) from the same bag, the two bars being present in the mold side by side at a short distance with the handles extending on both sides.
• an operator or a mechanism grabs the two bars still connected by the fracturable injection bridges while they are still hot, to fold them against each other so as to interpenetrate the snap-on locking means with which the bars and possibly the handles are provided.
• Such an operation does not present any particular difficulties in the case of bags without bellows.
• British patent 1,367,952 describes a method and a device for welding plastic bars provided with handles inside the opening of bags comprising bellows. No details are given on the length of the bars and this document simply discloses the idea of automatically carrying out the insertion of bars which was carried out manually. This device was never implemented and we continued to place the bars manually in the bags.
• French patent 2,027,997 describes a process allowing the welding of the bars inside the opening of a bellows bag, the bars having a length which is practically equal to the width of the bag. To carry out this operation, this document provides for making notches or cuts in the bellows so as to obtain extensions of the flat faces of the bag and not to be hampered by the presence of the bellows. Such a process requires an additional operation on the bag and leads to a weakening of its solidity.
• German patent 1,937,480 describes a device for positioning a bar in which the length of the bars is sufficiently short so as not to be obstructed by the bellows.
• the present invention proposes to remedy these drawbacks and to provide a method of manufacturing bags of flexible material such as plastic or paper of the bellows type, provided with bars with handles, which eliminates the manual intervention hitherto necessary and therefore reduces the cost price.
• Another objective of the invention is to provide a device for the implementation of this method which is simple and reliable.
• Yet another objective of the invention is to eliminate the operations of assembling bars at the outlet of the mold, thereby increasing the rate of molding and eliminating an operator or a mechanism.
• the subject of the invention is a method of manufacturing bags made of flexible material, in particular plastic or paper, having lateral bellows, in which a flattened sheath of plastic is produced, the two edges of the sheath are folded inwards so as to form two lateral bellows, the sheath is cut into individual bags whose bottom is welded, there is produced by injection molding, for each bags, two bars each carrying a handle as well as closure means capable of cooperating with each other on the bars whose length is clearly greater than the distance separating the two bellows, and the bars are fixed by welding or gluing by their external faces against the internal edges of the opening of the bag, characterized in that one brings separately the two bars opposite the opening and, separating the two edges of the opening from one another, the two bars arranged simultaneously are introduced s parallel to each other but separated by a space allowing the passage of the two bellows between the bars, after which the internal faces of the two edges of the bag are fixed against their respective bars.
• the method is implemented continuously with the formation of the bag from the sheath and the bars are advantageously presented in stacks, for example, from reserves or bar chargers arranged symmetrically with respect to the plane of the bag. .
• action is preferably taken by suction on the external faces of the two edges.
• One can, simultaneously, tighten the bellows by exerting on their internal top a push in the plane of symmetry of the bag.
• the positioning and welding of the bars in the opening of the bag can be carried out at the same time as the cutting and welding of the bottom of the bag.
• the method according to the invention results in a high-speed production of bags, for example, of the order of 20 bags per minute, and this under conditions of very high reliability, and eliminating the need to collect the two bars of the same bag after they have been molded, which simplifies the mold and increases its production rate while eliminating the work station or the mechanism responsible for bringing the two bars out of the mold .
• the invention also relates to a device for the implementation of this method, characterized in that it comprises means making it possible to present a sheath or a bag already cut from the sheath in a flattened position, means, preferably by suction, making it possible to separate, by a certain distance, the two edges of the opening of the bag and to unfold, at least partially the bellows, means for presenting, on either side of the plane of symmetry of the bag, two bars arranged in parallel and spaced from each other by a sufficient distance so as no longer to be hampered by the presence of the bellows, and introduce said bars into the opening thus formed in the vicinity of the internal faces of the corresponding edges of the bag, and means for welding or gluing said edges against the bars.
• the means presenting and maintaining the bars in the opening of the bag are designed so as to allow, once the bars are placed in the opening, the bringing together of the two bars towards each other, and possibly the snap of their mutual assembly means, for example, under the effect of welding jaws, which makes it unnecessary to insert a support piece between the two bars during welding, and then authorizes the delivery of a closed bag .
• the presentation means of the bars are preferably supplied by two bar loaders arranged symmetrically with respect to the plane of symmetry of the bag and associated with means such as movable fingers to release the end bars, facing each other, from the two chargers and the bring it into the opening of the bag.
• the bars can be made so that they can be snapped against each other to form two stacks that are stable by themselves, which eliminates the need for chargers.
• the device preferably comprises a station ensuring both the cutting and the welding of the bottom of the bag at the same time as the positioning and the welding of the strips and, in this case, a bag position detector is advantageously provided such as, for example, an optical sensor sensitive to an inscription repetitively disposed on the sheath, which can advantageously be presented on a coil or even be fabricated in place, in the case where it is produced by folding and welding a edge.
• the bags can be evacuated advantageously by planning to bring the bag or the sheath, during the positioning and welding of the bars, on a table which is capable of tilting after the implementation of the various operations so the bag slides by its own gravity into a receiving device allowing automatic counting and stacking.
• bars with completely conventional handles provided with lugs and mutual snap-on holes it is also possible to provide for giving the snap-on hole a dimension, in the direction of the length of the strip, greater than the corresponding dimension of the lug or male latching element so as to allow, even in the event of differential withdrawal of the cooling strips after molding, assembly by latching of the bars and the invention also relates to bags having such bars.
• FIG. 1 represents a view of a bag manufactured according to the invention
• FIG. 2 represents a view of a bag with a variant of bars according to the invention
• FIG. 3 represents a schematic elevation view of a device according to the invention
• FIG. 4 diagrammatically represents the opening of the bag front view at the time of insertion of the bars
• Figure 5 shows a view similar to Figure 4, in vertical section.
• the bag shown in Figure 1 has two main faces 1 and two side bellows 2 with a bottom 3 closed by welding.
• the opening of the bag has, inside, two stiffening bars 4 of molded plastic material provided with their handles 5 as well as snap-on assembly means such as lugs 6 and holes 7. It is thus possible to bring the two bars with their handles, one from the other and, making the pins penetrate the holes, assemble the bars and handles to each other and close the bag.
• FIG. 2 it can be seen that the lugs and circular holes in FIG. 1 can be replaced by dry lugs square or rectangular tion 8 penetrating into rectangular or oblong holes 9 of greater length, which allows closing even if the distances between pins and holes of the same bar are slightly different from the corresponding centers of the other bar.
• the device for implementing the method according to the invention comprises a coil 10 supporting a winding of a flexible plastic sheath 11 which is unwound under tension by being returned on a roller tension 12 to a bellows forming station 13 of a completely conventional type in which the two bellows 2 are formed, on the two sides of the sheath 11.
• the sheath can come from extrusion or be obtained by folding and welding of a film.
• This bellows training station 13 will not be described in more detail, being of a very usual type.
• the sheath with its bellows passes through the hot air heating device 14, of an equally conventional type, after which, the sheath, with its bellows, passes over a set of three cylinders 15, of which a cylinder is recalled with an effort on the other two so as to ensure fixing of the folds, previously heated, of the bellows.
• the sheath with its bellows then passes into a storage area 16 of a usual type whose variable length makes it possible to tune the continuous and step-by-step rhythms of the parts of the device upstream and downstream of the area 16.
• rollers 18 then return the sheath to a table 19 capable of pivoting between the position shown in solid lines and the position shown in broken lines around an axis 20 by virtue of the traction of a jack 21.
• the table 19 comprises in particular two rigid crosspieces 22, 23.
• the cross member 23, the position of which can be adjusted by a jack 30, is integral with the station 31 for positioning and welding bars 32 similar to bars 4 but provided with a rib 33 and a handle of reinforced thickness 34.
• This station comprises a plate 35 integral with the cross-member 23 and ending with a porous transverse suction element 36 followed by a fixed heating jaw 37. It also comprises a movable upper assembly having, at the end of a suitable support, an elongated suction element 38 and a heating jaw 39, the assembly being actuated by a jack 40.
• the distance between the welding jaw 27 and the set of jaws 37, 39 corresponds to the length of the bag and can be adapted to bags of different lengths by acting on the jack 30.
• the bars 32 are freely stacked in two chargers 41, 42 arranged symmetrically on either side of a horizontal plane 43 passing a little above the plate 35.
• These chargers have, at their two opposite ends, means dispensing individual bars comprising, for example, rotary members with pins and fingers pushed back by jacks 44, 45.
• the control of these mechanisms is ensured so that the loaders simultaneously present an upper bar and a lower bar each arranged horizontally , the two bars being parallel and located in the spacing shown in FIG. 4.
• a bar gripping mechanism is advantageously provided between the two magazines 41 and 42. This mechanism not only is capable of presenting the bars horizontally and parallel in the position shown in Figure 4, but also to move the assembly ble of these corx bars horizontally in the direction of the jaws 37, 39, with their associated suction elements 36, 38.
• the bars can be temporarily secured to one another by snap-fastening, one can do without the chargers and provide, for example, simple means for guiding the stacks of bars.
• the bar gripping mechanism which grasps the two bars coming from the loaders, can, for example, have two crews movable simultaneously in the horizontal plane towards and away from the bag and movable in opposite directions in the vertical direction for s '' approach or move away from each other.
• Each crew can comprise, for example, a first bar engaging in the female part of the rib 33 by marrying its internal shape without exceeding the bar and a second bar fitting to the male part of the rib 33, the two bars being clamped towards each other in the manner of jaws which, when clamped, hold the bar in the horizontal position shown in FIG. 5.
• the operation is as follows: The sheath 11 with its bellows is delivered to the table 19 by the rollers 18 and slides horizontally until its end is disposed opposite the jaws 37, 39, in the axial position shown in the figure 5.
• the obtaining of this position that is to say the stopping of the movement of the rollers 18, is controlled by the position detector 29.
• the rollers 18 being stopped, the sheath is stationary while the storage area 16 supports the sheath part which is located upstream and which, coming from the reel 10 and passing through the stations 13, 14 and 15, runs continuously.
• the devices 26 and 28 are actuated and cause the cutting of a section of sheath which must form the bag as well as the welding of the bottom 3 of the bag by the heating jaw 27.
• the jack 40 causes the descent of the 'set of elements 38, 39 so that the end of the bag intended to form the opening of the bag is caught between the elements 36, 37, on the one hand, and the elements 38, 39, on the other hand.
• the elements 36 and 38 are connected to a source of vacuum and the edges of the bag are applied by suction against these elements and, consequently, against the jaws 37 and 39.
• the jack 40 then causes movement in the opposite direction until the position shown in FIGS. 4 and 5 is obtained in which the two edges of the sheath 11 forming the bag are spaced from one another, the bellows taking the semi-open position shown in FIG. 4.
• the delivery mechanisms of the magazines 41 and 42 took two bars and brought them into a position spaced apart on either side of the plane 43 as shown in FIG. 4.
• the presentation mechanism is then advanced and the bars 32 advance horizontally until they come to occupy the position of FIG. 5 in which their parts intended for welding are arranged inside the opening without being obstructed by the bellows, as seen in FIG. 4.
• the cylinder 40 then lowers the heating jaw 39 in the direction of the arrow and the bars are finally applied one against the other while the heating jaws are supplied with electric current and are heated rapidly to cause the welding of the two walls 1 on the external faces of the respective bars 32.
• the station formed by the table 19 rocks around its axis 20 and the bag slides into a receiving device 46 designed to count the bags and stack them to deliver them to a suitable store.
• the device then returns to its initial position and the rollers 18 are again actuated to form a new bag.

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• Making Paper Articles (AREA)
• Bag Frames (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=9317391

Family Applications (1)

Country Status (4)

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Family Cites Families (6)

• 1985
  • 1985-03-20 FR FR8504127A patent/FR2590520B1/fr not_active Expired
• 1986
  • 1986-03-13 JP JP61501585A patent/JPS62502252A/ja active Pending
  • 1986-03-13 EP EP86901892A patent/EP0215083A1/de not_active Withdrawn
  • 1986-03-13 WO PCT/FR1986/000082 patent/WO1986005442A1/fr not_active Ceased

Non-Patent Citations (1)

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