TW202227262A - An apparatus and a method for manufacturing block bottom bags, and a block-bottom bag - Google Patents

Abstract

The invention relates to an apparatus and a method for manufacturing block bottom bags, and a block-bottom bag. A single apparatus to make block bottom bags is disclosed incorporating features such as inspecting the thermoplastic film for flaws, transferring the thermoplastic film at high speed, rejecting defective parts of the thermoplastic film without interrupting the production flow, and more, in a holistic manner. Accordingly, the apparatus of invention has a thermoplastic film preparatory means (b), an inspection and sensing means (c), a thermoplastic film cut length cutting means (d), a transportation means (e), a defect rejection means (f), a top and bottom edge opening means (g), a valve patch application means (h), a top and bottom end folding means (i), a cover patch application means (j), a stacking means (k), and a main automation and controlling means (l) consisting of controlling unit (41) for controlling the process of manufacture of bag (32) from film.

Description

Square bottom bag and device and method for making square bottom bag

The present invention relates to a device for making square bottom bags from tubular films using thermal welding, making the bags recyclable.

Thermoplastic bags are known, which are formed from tubes of thermoplastic material that are cut transversely to the axis of the tube and then joined together along the cut lines. The main disadvantage of these known bags is that when filled, they assume the shape of a pillow or cushion, which is disadvantageous when it is desired to stack the bags and one of the waste of material since the "pillow corners" will only hold a small amount of material shape.

On the other hand, known "square bottom" bags or parallelepiped bags have been constructed in the past using one or more layers of paper or similar material and using an adhesive to hold the bottom forming part in place. Bottom molding components are typically formed by suitable cutting and folding in the opposite ends of the blanks or tubes from which the bags are constructed (which are not fully recyclable according to current environmental codes/standards).

Square bottom bags or pouch bases or ends are typically formed in machines in which lay-flat tubular members of thermoplastic film are folded into one piece at their equal ends. Bag making machines typically include several stations designed to perform specific functions that ultimately result in the manufacture of a complete square bottom bag. However, due to the evolution of these machines over the past few decades, especially due to the increased speed at which the machines have grown, several new aspects need to be viewed. such as less time for changing rolls at the unwinding station to reduce production losses, fast and even cutting of the cut pieces and transfer from one direction to another, good bonding of sheets to top and bottom for Forming a bag and efficient transport are some of the main aspects of the machine to look at. A typical machine includes processing stations such as for opening the ends of the continuous conveying tubular section into bottom squares forming an open bottom and for securing and closing the bottom using valve leaf or tube insertion and for attaching bottom cover plates to Close the station on the bottom.

As packaging requirements and consumer demands evolve, many new features need to be incorporated into bag converting machines. Furthermore, square bottom bag machines are conventionally used to process webs of fabrics, these bags are prone to moisture and are not perfectly waterproof, thus requiring waterproof bags with the highest product protection. Due to the known technology of these machines and the limitations of the procedures they employ to use their work, woven bags with many modifications and adaptations of units and parts are required to produce a bag using thermoplastic film. Some of these are related to aspects such as: high-speed stretching and edge guiding of thermoplastic film rolls; pre-treatment of thermoplastic film surfaces such as perforations, anchor holes; detection of thermoplastic film defects; high-speed cutting; high-speed transfer Thermoplastic films; return of defective parts of thermoplastic films without interrupting the production process, etc., which are not considered in a holistic manner. Several of these aspects have been considered individually, however, there is no single device that incorporates all of these aspects. Also, the synchronous control of all these units working as a single machine is a huge challenge.

In one of the patent applications CN1201923C ('1923), it discloses a double-layer polyethylene valve bag and a method of making the same. This double-layer bag is made by a complicated method to cover the polyethylene inner and outer tubes with pinholes so that the pinholes on the inner and outer tubes are not in the same position, and the oblong openings at both ends of the double-layered tube are folded into Multi-layer multi-edge geometric upper and lower bottom surfaces, a valve port is installed on the short edge of the upper bottom surface, a layer of fabric is pasted on the upper and lower bottom surfaces, and then the heated high pressure mold is applied to cover the jacket mold. The one-time multi-edge pressure welding of the lower bottom surface and the upper bottom surface of the lining layer using a liner mold makes it possible to form a double-vented double-bottom three-dimensional rectangular polyethylene valve bag. However, the patent ('1923) does not disclose any apparatus for making bags or an automated process for making bags to increase production rates.

Another patent application CN102328774 ('774) discloses a packaging bag, a square bottom valve bag containing thermoplastic plastic and a method of making the same. In this patent ('774), the sealing at the ends is done by hot air and the cover sheet applied at the ends to seal the bag can be plastic or cloth, this kind of joining of different materials requires precision and is therefore costly time, this will eventually slow down the production rate. Furthermore, the patent ('774) does not disclose any apparatus for making bags or an automated process for making such bags.

The present invention differs from these prior art arrangements by the fact that the "square bottom" or parallelepiped bag is constructed entirely of heat-sealable thermoplastic material, wherein the bottom is formed contactlessly and joined to the bag by a heat welding step the side wall. Additionally, the pouches of the present invention may be formed from one or more layers of thermoplastic material.

In addition, therefore, there is also a need to provide a single apparatus for making square bottom bags that incorporates features such as the following in a holistic, seamless, and advantageous manner: detecting defects in thermoplastic films; Transfer thermoplastic films; return defective parts of thermoplastic films without interrupting the production process, and more.

Thermoplastic films can be produced from blown film extruders, which involve a process of extruding plastic through a circular die, followed by "bubble" expansion. Mainly polyethylene (HDPE, LDPE and LLDPE) but a wide variety of other materials are available as blends with these resins or as a single layer in a multilayer film structure, these include PE used to form thermoplastic films , PP, PA and EVOH.

Films of this type and bags made therefrom are widely used in industrial packaging (eg, shrink films, stretch films, bag films or container liners), consumer packaging (eg, frozen product packaging films, transport packaging shrink films, food cling film, packaging film, or forming, filling and sealing packaging films), laminating films (e.g. aluminum or paper lamination for packaging (e.g.) milk or coffee), barrier films, films for packaging medical products, Agricultural films (eg, greenhouse films, crop forcing films, silage films, silage stretch films).

In accordance with the present invention, apparatus and procedures for making square bottom bags using suitable thermoplastic films are now disclosed.

Thermoplastic films, which are fragile in nature, need to be handled and handled very precisely during bag making. The various procedures involve the need for an accurate and specific functionality such that the production rate is high (preferably 120 to 140 bags per minute or more), and at the same time achieve bags of the desired strength when filled with 40 to 50 kg of material Withstands drop test.

The device of the present invention has the following stations or units with their specific functionalities: a) A thermoplastic film roll feed member comprising a thermoplastic film edge guide and stretching unit b) a thermoplastic film preparation member, which itself includes A preparation member, which, as the case may be, consists of a thermoplastic film perforated member Positioning hole punching member, and A thermoplastic film cleaning member c) a detection and sensing member, which includes a detection unit d) A thermoplastic film cutting length cutting member consisting of a high-speed cross-cutting machine e) a transport member with a transfer unit f) a defective retraction member for rejecting defective parts into the retraction area g) a top and bottom edge opening member comprising An edge-opening member is selected, which is positioned vertically An opening member with a rotating mechanism h) A valve plate unit, which is used as storage, transportation and heat welding/sealing member of the valve plate i) a top and bottom folded member j) A cover slip unit, which serves as a storage, transport and thermal welding member for cover slips k) a stacking member l) One main automation and control component

In some embodiments of the invention, some of the aforementioned stations are combined.

The main object of the present invention is to provide an apparatus for making square bottom bags from recyclable thermoplastic films.

Another object of the present invention is to provide a monolithic device adapted to manufacture square bottom bags based on recyclable thermoplastic films by incorporating features such as the following in a holistic manner: Defects; transfer of thermoplastic film in high-speed programs; return of defective parts of thermoplastic film without interrupting the production process; thermal welding of valve plates and cover plates, etc.

A further object of the present invention is to provide an apparatus suitably adapted to process thermoplastic films to form square bottom bags.

Yet another object of the present invention is to provide an automated device for making square bottom bags from recyclable thermoplastics.

Yet another object of the present invention is to provide an automated process for making square bottom bags from recyclable thermoplastics.

Detailed Description of the Invention with respect to the Figures :

According to the invention, there is provided a device for making cross-bottom bags from flat tubular cut-outs (2) of film made from thermoplastic film rolls (1).

As shown in Figures 1 and 1A, the device of the present invention includes various units enumerated below and having specific functionalities: Ø A thermoplastic film roll feeding member (a) consisting of A stretching unit (3), which is used for the role of stretching the film Optional - thermoplastic film edge guide (not shown) Ø Thermoplastic film preparation member (b), which consists of a preparation member, which is optionally composed of thermoplastic film perforation units (5) A preparation member consisting of a positioning hole punching member (44) and a thermoplastic film cleaning member (not shown) as appropriate Ø A detection and sensing member (c), which consists of a detection unit (4) Ø A thermoplastic film cutting length cutting member (d), like a high-speed cross-cutting machine and a beveling machine unit (7) o a transport member (e) consisting of the following A lateral transfer unit (8) for transferring the film from the X direction to the Y direction Ø A defective retraction member (f), which rejects defective film cut pieces to the ejection area (40) Ø A top and bottom edge opening member (g) consisting of an end opening unit (9) having One of the vertical positioning edges open the component as appropriate It has an opening member with a rotating mechanism Ø A valve plate application member (h) consisting of a valve plate unit (10) for storing, transporting and heat welding the valve plate to one end of the membrane Ø A folding member (i) for the top and bottom folding of the membrane (14, 15) Ø A cover sheet application member (j), which consists of a cover sheet unit (16) for storage, transportation and thermal welding of the cover sheet o a stacking member (k) consisting of a stacker unit (31) for storing processed bags made of film Ø A main automation and control member (m) consisting of a control unit (41) for controlling the procedure of making bags (32) from the film

Some of these units can be collectively called out in configurations placed at sides A and B, as can be seen from FIG. 1 . The film movement is shown by the arrows in the X and Y directions, the main purpose of the direction change of the bag from X to Y is to allow easy handling of the sides of the bag.

A thermoplastic film roll feed member (a) supplies a thermoplastic film roll (1) supported on a stretcher unit (3). The roll is stretched in the form of a tubular film. The stretching machine unit (3) can be single station or multi-station. Here, single and multi-station depicts the number of rolls that can be installed on the stretcher unit such that an ideal roll is installed opposite the active roll. During a roll change, the operator quickly changes from an empty roll to a full roll, which minimizes roll change lead time. Therefore, the main aspect of a multi-station stretcher unit is the presence of a plurality of side-by-side stations, each station having a unique shaft (45), so that multiple rolls can be loaded, which additional rolls can be utilized during replacement.

Now, the tubular film is advanced through the thermoplastic film making member (b) comprising a perforated unit (5) in which there is at least one set of perforated rolls (6). The perforated roller (6) comprises a plurality of pin-shaped fins protruding outwards, which are called nano due to their equally small size (preferably in the range of 0.5 to 0.7 mm diameter) perforation. The needles are preferably spread over the roll at a density of 80 to 90 needles per square centimeter and form a cluster. Due to the clustering of the needles and their iso-dense nature, they create nanoperforated pores in the film.

The term nano in nano-perforation is well known to those skilled in the art, so that it refers to the size of the needle, which is very small when compared to the normal size used to make bags from film. As an example, the normal size of the needle diameter may preferably be in the range of 1 to 1.5 mm, wherein the nanometer size such as the needle diameter may preferably be in the range of 0.5 to 0.7 mm. These holes are essential for removing trapped air inside the tubular thermoplastic film during filing of the bag.

In addition, punching members (44) are used as appropriate to make positioning holes and complete the cleaning of the thermoplastic film. Cleaning can be accomplished by a jet of air traveling over the tubular membrane at a low output velocity.

The tubular film now travels through one of the detection and sensing members (c) comprising the detection unit (4), so that any defects in the film can be monitored and can be processed to the side opening unit (after being cut by the cutting unit (7) 9) Remove the defective area before. The detection unit (4) further comprises a transmitter (42) and a receiver unit (43) which captures an image of the thermoplastic film traveling through it, and any change in color of the thermoplastic film or any cracking or breaking is detected by the transmitter/ The receiver unit indicates and detects defects. The defect locations are sensed and stored in a database in the control unit (41).

In one of the embodiments, a detection and sensing member (c) is placed before the preparation member (b). Once a defective tubular film is detected by the detection unit (4), the machine will stop, thereby stopping the further advancement of the tubular film into the perforation unit (5). This activity will increase the lifetime of the perforated unit (5), since only defect-free films are allowed to travel through the perforated unit (5). Defects can be in the nature of bulges, tears, or protrusions of any kind that will obstruct the perforation needle.

To make a desired cut length of the bag, the thermoplastic film is advanced through a thermoplastic film cut length cutting member (d) comprising a cutting unit (7), wherein the film is cut into pieces having predetermined lengths generally depending on the size and shape of the bag. The cutting of the thermoplastic film is done according to the feedback stored in a database. A tubular film is obtained which is now cut by the cutter unit (7) into cut pieces (2) of the desired length with top and bottom ends (2A, 2B). In general, cold cutting methods are used to cut the film into the desired cut pieces (2), which has one advantage over thermal cutting operations. During the thermal cutting operation, the upper and lower layers of the film are sealed together, which requires extra work to separate in a subsequent stage.

A high speed cutter unit (7) is incorporated to increase the speed of the cutting operation by up to 25% to 30%, ie 120 to 140 bags/min. Here, a signal from the detection unit (4) is sent so that defective parts or areas containing defects are cut without wasting the film. Therefore, the cutting machine is adapted to cut the thermoplastic film with high accuracy at the desired program speed. Furthermore, this adaptation of the cutting unit (7) is done due to the cross-cutting operation performed by the cutting machine. Thanks to this operation, the machine can run continuously without reducing speed.

In conventional bag cutting systems, the movement of the cutting machine is perpendicular to the movement of the cutting element, which restricts the machine from operating at high speed because the machine has to slow down during each cutting stroke. This type of mechanism may also be referred to as time travel. Stop and go program.

The cutting pieces ( 2 ) are transported to the further station by means of transport means (e). The transport member comprises a transverse transfer unit (8) comprising a positive transport effect at a speed much higher than a system in which the cutting pieces (2) are transported in a single plane on a single conveyor Grip transfer mechanism. This transfer unit (8) is able to transfer the cut pieces (2) of thermoplastic film from the X-direction to the Y-direction at a higher speed without slowing down the machine.

Defective thermoplastic film pieces sensed by the detection unit (4) are cut by the cutter and removed from the in-line process via the defect return member (f) into the ejection area (40), so that only the defect-free pieces continue and so on until Transportation to further downstream stations.

In one of the embodiments, the lateral transfer unit (8) can be constructed such that the cutting element (2) does not stop but can be transferred in an oblique pull. This oblique pulling approach causes the cutting element (2) to gradually move in an oblique plane and change the direction from X to Y.

The defect-free pieces are now transferred to an edge opening member (g) comprising an end opening unit (9), wherein the top and bottom ends (2A, 2B) are opened for the purpose of folding. Opening of the ends can be performed using a rotating mechanism or a mechanism operating in a vertical plane. The sides are opened by a suction member or any kind of member (such as a two-layer clamp configuration of an openable membrane) before being subjected to a rotating mechanism. The opened layer of the film is subjected to contour structures that rotate so that during movement in the Y direction, the bag is opened. The end opening station (9) is located at both side A and side B, so that the same opening of the top and bottom ends of the film cutter (2) is obtained.

At the bottom end (2B) of the membrane cutting element (2), a valve plate (11) is now glued. A valve disc applying member (h) includes a valve disc unit (10), the valve disc unit (10) further comprising a shaft member (45) mounted to freely rotate so as to continuously and smoothly complete the supply of the valve disc (36) ) on the valve coil (12). The valve plate unit (10) further comprises a piece of welding unit (13) which cuts the valve plate (36) into a valve plate cutting piece (11) having a desired length and sticks it on the bottom end of the film cutting piece (2).

Furthermore, more details of the wafer bonding unit are shown in FIG. 2, which are described in detail in a later stage of the description of the specification. The valve plate (11) can be a membrane of the same material as the membrane cutting element (2) or can be made of a composite material that provides sufficient strength to the valve and can be firmly adhered to the substrate. The fixing of the valve plate (11) and the cutting element (2) can be done by any kind of means, such as thermal welding, hot melt gluing or by ultrasonic methods.

The cut piece (2) with the open end is sent to a folding member (i) comprising a top folding unit (14) and a bottom folding unit (15) for folding to form the bottom of the square bottom bag. Both the top and bottom folding units (14, 15) are identical in construction and are placed at side A and side B, respectively.

In addition, the folded end of the cutting element (2) is provided with a cover to seal the bag end forming the sealed square bottom bag. The thus folded end of the cutting piece (2) is transferred to a coversheet application member (j) comprising a coversheet unit (16) which further comprises a coversheet roll (18). These rolls of cover sheets supply cover sheets (37) separately to the bottom and top ends of the folded film cutters (2). This individual supply of cover sheets (37) can be facilitated by providing two cover sheet rolls (18) identical in construction and mounted on a single frame. The cover sheets (37) supplied from the cover sheet roll (18) are cut into cover sheet cut pieces (17) to the desired length and glued on the top and bottom of the film cut pieces (2). The cutting and pasting mechanism is completed by the sheet welding unit (13).

The device of the present invention includes a plurality of chip bonding units (13), so that the method of pasting the chips can be individually completed at different desired stations.

The now formed bag (32) is further conveyed into the stacker unit (31) by the stacker member (k) at the desired position for stacking.

All program parameters at each unit level form (a to k) are stored in the main automation and control component (m) as a database and provide feedback to the different units so that the units can function and can be individually in operation to change.

In one embodiment, the apparatus of the present invention can produce a thermoplastic square bottom bag using only the following units: Stretch unit Cutting unit Lateral transfer unit Top and bottom opening units Valve application unit Top and bottom folding units Cover sheet application unit, and Stacking unit

In another embodiment, optional units such as a perforation unit, inspection unit, and retraction unit would enhance the speed of the machine so that defective cuts of thermoplastic film can be sensed and easily ejected from the production line.

FIG. 2 shows a piece of welding unit ( 13 ) that is identical in construction to apply both the valve sheet ( 11 ) and the cover sheet ( 17 ) but placed in different positions, as can be seen from FIG. 1 . The sheet welding unit (13) includes a frame (19) on which a first idler roller (20), a second idler roller (21), and a third idler roller (22) are mounted so that it will Tension is provided to the sheet stretched from the rolls (12, 18). A pressure roller (23) is also mounted on the frame (19) so that it exerts less pressure on the sheet (36/37) at the first end (33), and the hot drum (27), the master cutter A roller (24) is present at the second end (34) so that the cutting of the sheet (36/37) can be properly accomplished. The master cutter roll (24) contains a set of blades or sharp knives that cut the sheet into pieces by rotating about an axis (35). The hot drum (27) preheats the sheet cutting element (11/17) so that in a subsequent stage, the sheet can be adhered to the film cutting element (2) with good adhesion.

A first sensor (25) is provided to sense the edge of the sheet (36/37) so that any lateral displacement of the sheet (36/37) can be corrected. A second sensor (26) is provided to sense the print marks (if any) so that the sheet is cut at a predetermined length by sensing the print marks.

The aforementioned print marks are pre-printed on the sheet (36/37) with a predetermined length. This predetermined length is the sheet length (L) required to cover the top and bottom folded ends of the bag (32), as shown in FIG. 4 . The print mark sensor or second sensor (26) is specifically designed to recognize the print and instruct the master cutter (24) to cut the sheet (36/37) to a predetermined length.

In one embodiment, the apparatus of the present invention can also produce a thermoplastic film bag (32) without the use of the first sensor (25). In this case, a lateral displacement of the sheets (36/37) which can hinder the quality of the produced bag (32) can be observed.

In another embodiment, the apparatus of the present invention can produce a thermoplastic film pouch (32) without using the second sensor (26) for pouches (32) produced from unprinted thermoplastic film. Unprinted films do not include a printed mark after each cut length location or printed area. The basic meaning of the print mark sensor (26) is that it senses the print mark and cuts the film to a desired length so that the printing of the film is not hindered.

In yet another embodiment, the position of the idler rollers (20, 21, 22) can be altered in position such that a tension is maintained in the sheet (36/37).

The valve sheet cutters ( 11 )/cover sheet cutters ( 17 ) are sucked by suction rollers ( 28 ) so that they are conveyed and placed perfectly on the film cutters ( 2 ) without any lateral displacement. However, the suction cylinder (28) includes a plurality of micro-holes (38) through which suction is generated. As shown in Figure 3, a heat gun (30) injects a burst of air between the sheet (11/17) and the film cutter (2) through a nozzle (39) so that it creates a heating zone. The temperature of the hot zone can be adjusted by adjusting the amount of air to be injected by the heat gun (30). Keep the temperature of the heating zone just below the melting temperature of the film or better plastic (ie in the range of 80° to 100° or better 95°) so that the film (2) and sheet (11/17) do not Melted but produced a good bond. There is a support or pressure roller (29) that provides a base to the film (2) and a positive drive to the film (2). Once the flap is in place, the square bottom bag is ready to be transported to the stacking station (31).

All operations are controlled in a synchronized manner using an electronic control and automation system. The main control system has facilities for inputting the required control and program parameters through the man-machine interface. In one embodiment, some stations are manually operable.

Figure 4 shows a bag (32) with a square bottom end made of thermoplastic film cut (2), with valve cut (11) at one end and cover cut (17) at the other end.

According to the present invention, it differs from prior art arrangements in that a "square bottom" or parallelepiped bag is constructed entirely of heat-sealable thermoplastic material, wherein the bottom is formed using an external cover/seal plate using a non-contact heat welding step And joined to the side wall of the bag. The pouches of the present invention may be formed from one or more layers of thermoplastic material. In addition, the film material of the bag body and its sealing plate can be of a similar type or of a different type.

The present invention also discloses a method for making square bottom bags from thermoplastic film, which involves the following steps: The thermoplastic film roll (1) is stretched from the stretcher unit (3). The film now enters the perforated unit (5), where nano-preformed marks are produced on the film by means of a perforated roll (6). Furthermore, the film is brought into the detection unit (4) and detected in the detection unit (4). The inspected film is cut into desired lengths or cut pieces (2) by the cutting unit (7), so that the opened top (2A) and bottom (2B) ends are produced. The film cutting piece (2) is transferred from the X direction to the Y direction by the transfer unit (8). The opening of the membrane (2) at the ends is accomplished by the end opening unit (9). In addition, glue the valve disc cutting piece (11) to the bottom end (2B). Process the valve disc cut (11) by cutting the valve disc roll (12) to the desired length by means of the disc welding unit (13). Now fold the top and bottom ends (2A, 2B) of the film cutting piece (2) by means of the top and bottom folding units (14, 15). In addition, glue the cover cut pieces (17) to the folded top and bottom ends (2A, 2B). The cover sheet cut (17) is processed by cutting the cover sheet roll (18) to the desired length by means of the sheet welding unit (13) to form a bag (32) with a square bottom end. The bag (32) is further sent to the stacker unit (31) for further storage.

Accordingly, the device of the present invention has several embodiments.

In a preferred embodiment, the present invention discloses an apparatus for making square bottom bags from sections of tubular film. Characterization of the device is that the device includes the following stations: - a thermoplastic film roll feed member (a) consisting of a stretching unit (3) for the role of stretching the film and optionally a thermoplastic film edge guide; - a thermoplastic film preparation member (b), which itself is composed of a preparation member having a selected thermoplastic film perforating unit (5) or a selected positioning hole punching member (44) and a thermoplastic film cleaning member; - a detection and sensing member (c), which consists of a detection unit (4); - a thermoplastic film cutting length cutting member (d) in the form of a high-speed cross-cutting machine or a beveling machine unit (7); - a transport member (e) consisting of a transverse transfer unit (8) for transferring the film from the X direction to the Y direction; - a defective return member (f), which sends the defective film cut to the ejection area (40); - a top and bottom edge opening member (g), which itself consists of an end opening unit (9) having a vertically positioned edge opening member and an opening member with a rotating mechanism; - a valve plate application member (h) consisting of a valve plate unit (10) for storing, transporting and thermally welding the valve plate to one end of the membrane; - a folding member (i) for the top and bottom folding of the membrane (14, 15); - a cover sheet application member (j) consisting of a cover sheet unit (16) for storage, transport and thermal welding of the cover sheet; - a stacking member (k) consisting of a stacker unit (31) for storing processed bags made of film; and - A main automation and control member (m) consisting of a control unit (41) for controlling the procedure of making bags (32) from film.

In a further embodiment, the stretcher unit (3) is a single-station or multi-station, wherein in the case of a multi-station stretcher unit, a plurality of side-by-side stations are provided, each station having a unique shaft (45) to facilitate the loading of multiple volumes.

In another embodiment, the film perforating unit (5) is provided with at least one set of perforating rollers (6) comprising 80 to 90 needles per square centimeter protruding outwardly in a cluster A plurality of pin-shaped fins densely distributed on the roller.

In yet another embodiment, the diameter of the needle is in the range of 0.5 mm to 0.7 mm.

In yet another embodiment, the detection unit (4) comprises a transmitter (42) and a receiver unit capable of capturing an image of the thermoplastic film traveling through it and detecting any defects or changes in the color of the thermoplastic film (43), or any cracks or breaks are indicated by the transmitter/receiver unit and the defect is detected.

In yet a further embodiment, the cutting member (d) comprises a cutting unit (7) operating according to a cold cutting principle.

In a still further embodiment, the edge opening member (g) comprises an end opening unit (9), wherein the top and bottom ends (2A, 2B) are opened using a rotating mechanism or a mechanism operated in a vertical plane, and wherein The sides are opened by a suction member or any kind of member (such as a clamp configuration of two layers of openable membrane) before being subjected to a rotating mechanism, and wherein the opened layer of the membrane is subjected to contour structures that rotate such that in the Y direction During this movement, the bag is opened.

In another embodiment, the valve plate applying member (h) includes a valve plate unit (10), which itself includes a valve plate unit (10) that is mounted to rotate freely so as to continuously and smoothly complete the application of the valve plate (36). Supply the valve sheet roll (12) on a shaft piece (45), and cut the valve sheet (36) into valve sheet cutting pieces (11) of desired length and stick it to the bottom end of the film cutting piece (2) One piece of welding unit (13) above.

In yet another embodiment, the sheet welding unit ( 13 ) fixes the valve sheet ( 11 ) with the cutting piece ( 2 ) using means such as thermal welding, hot melt gluing or by using ultrasonic methods.

In yet another embodiment, the folding member (i) comprises a top folding unit (14) and a bottom folding unit (15) folded to form the bottom of the square bottom bag, and wherein the top and bottom folding units ( 14, 15) are identical in construction and are placed at side A and side B, respectively.

In a further embodiment, the cover sheet application member (j) comprises a cover sheet unit (16) which itself comprises a separate supply of the cover sheet (37) to the folded film cutter (2) The bottom and top two cover rolls (18).

In yet a further embodiment, the two cover sheet rolls (18) are identical in construction and are mounted on a single frame.

In a still further embodiment, a piece of welding unit (13) is used to cut the cover sheet (37) into cover sheet cut pieces (17) to the desired length and glued on the top and bottom of the film cut pieces (2).

In another embodiment, the sheet welding unit (13) comprises: a frame (19) on which a first idler roller (20), a second idler roller (21), and a third idler roller (22) are mounted. thereon to provide tension to the sheet stretched from the rolls (12, 18); a pressure roller (23) which is also mounted on the frame (19) to apply pressure to the sheet (33) at the first end (33). 36/37); a heated drum (27), and a master cutter roll (24) present at the second end (34) to cut the sheet (36/37), wherein the master cutter roll ( 24) contains a set of blades or sharp knives, and wherein the hot drum (27) preheats the sheet cutting (11/17) so that in a subsequent stage the sheet can be adhered to the film cutting (2) with good adhesion .

In a further embodiment, a first sensor (25) is provided to sense the edge of the sheet (36/37) so that any lateral displacement of the sheet (36/37) can be corrected, and a second sensing is provided A cutter (26) senses the print marks and cuts the sheet in a predetermined length by sensing the print marks.

In yet another embodiment, a suction roller (28) is provided to suction the valve sheet cutter (11) or the cover sheet cutter (17) to convey and place the same on the cutter (2) , wherein the suction cylinder (28) includes a plurality of micro-holes (38) through which suction is generated, and a support or pressure roller (29) is provided to provide a positive drive to the membrane (2).

In a still further embodiment, a heat gun (30) with a nozzle (39) is provided to inject a burst of air between the sheet (11/17) and the film cutting member (2) to create a heating zone which heats The temperature of the zone is regulated by the amount of air to be injected by the heat gun (30).

In a yet further embodiment, the temperature of the heating zone is maintained just below the melting temperature of the film or better plastic (ie, in the range of 80°C to 100°C or better 95°) such that the film ( 2) and the sheets (11/17) do not melt but produce a good bond, after which the square bottom bag is ready to be transported to the stacking station (31).

In another embodiment, an electronic control and automation system is used to control all operations in a synchronized manner, and wherein the main control system has facilities for entering the desired control and program parameters through a human-machine interface.

In another embodiment, some stations are operated manually.

In another embodiment, a method of making square bottom bags from thermoplastic film using the apparatus disclosed in the preceding embodiments. This method has the following characterization steps: a) stretching a thermoplastic film roll (1) from the stretcher unit (3); b) advancing the tested film through a perforated unit (5), wherein nano-preformed markings are produced on the film by a perforated roll (6); c) Detection of the perforated film in the detection unit (4), whereby the perforated film is cut into cut pieces (2) by the cutting unit (7), so that the top (2A) and bottom (2B) ends which are then opened are produced ); d) using the transfer unit (8) to transfer the cutting piece (2) from the X direction to the Y direction; e) opening the membrane (2) at the ends using the end opening unit (9); f) Attach the valve plate cutting piece (11) to the bottom end (2B); h) Fold the top and bottom ends (2A, 2B) of the cutting element (2) using the top and bottom folding units (14, 15) respectively; i) Attaching the cover sheet cut (17) to the folded top and bottom ends (2A, 2B), thereby forming a pocket (32) with a square bottom end.

In yet another preferred embodiment, the present invention discloses a square bottom bag made of a tubular film, the bag having a parallelepiped bottom, characterized in that the bag is constructed entirely of heat-sealable thermoplastic material, wherein the bottom is It is formed by non-contact thermal welding and is joined to the sidewall of the bag.

While the above description contains many specificities, these should not be construed as limiting the scope of the invention, but as exemplification of one of its preferred embodiments. It must be appreciated that based on the disclosure given above, modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the scope of the present invention should be determined not by the illustrated embodiments, but by the scope of the appended invention claims and their legal equivalents.

1: Thermoplastic film roll 2: Film cutting pieces 2A: Top 2B: Bottom 3: stretcher unit 4: Detection unit 5: perforation unit 6: perforated roller 7: Cutting unit 8: Transfer unit 9: End Open Unit 10: Valve unit 11: valve plate cutting parts 12: Valve roll 13: Sheet welding unit 14: Top Folding Unit 15: Bottom Folding Unit 16: Coverslip unit 17: Cover Sheet Cutting Pieces 18: Cover Sheet Roll 19: Frames 20: First idler roller 21: Second idler roller 22: Third idler roller 23: Pressure Roller 24: Master cutting machine 25: First sensor 26: Second sensor 27: Hot Drums 28: Suction Roller 29: Pressure roller 30: Heat Gun 31: Stacker unit 32: bag 33: First End 34: Second End 35: Shaft 36: valve plate 37: Coverslip 38: Micropore 39: Nozzle 40: Ejection area 41: Control unit 42: Launcher 43: Receiver 44: Punching components 45: Shaft (a): Feeding member (b): Preparation of components (c): Detection and Sensing Components (d): Cutting member (e): Transport components (f): Return the component (g): Top and bottom edge opening members (h): valve plate application member (i): Folding member (j): Cover sheet application member (k): Overlapping member (m): Main automation and control components L: sheet length

Figures 1 and 1A show the device of the present invention in a schematic form.

Figure 2 shows a soldered/sealed device.

Figure 3 shows the working principle of the soldered/sealed device.

Figure 4 shows a square bottom bag made of recyclable thermoplastic film.

1: Thermoplastic film roll

2: Film cutting pieces

2A: Top

2B: Bottom

3: stretcher unit

4: Detection unit

5: perforation unit

6: perforated roller

7: Cutting unit

8: Transfer unit

9: End Open Unit

10: Valve unit

11: valve plate cutting parts

12: Valve roll

13: Sheet welding unit

14: Top Folding Unit

15: Bottom Folding Unit

16: Coverslip unit

17: Cover Sheet Cutting Pieces

18: Cover Sheet Roll

31: Stacker unit

32: bag

36: valve plate

37: Coverslip

40: Ejection area

41: Control unit

42: Launcher

43: Receiver

Claims (26)

A device for making square bottom bags from a tubular film, characterized in that the device comprises the following items: a thermoplastic film roll feeding member (a), which consists of a stretching unit (3) for stretching a roll of a tubular film and an edge guide for optional thermoplastic film; A thermoplastic film preparation member (b), which consists of a preparation member having an optional thermoplastic film perforating unit (5) or an optional positioning hole punching member and a thermoplastic film cleaning member; a detection and sensing member (c) , which consists of a detection unit (4); A thermoplastic film cutting length cutting member (d) in the form of a high-speed cross-cutting machine or a beveling machine unit (7); a transport member (e) consisting of a transverse transfer unit (8) for transferring the film cut pieces from the X-direction to the Y-direction; a defective return member (f), which sends the defective film cut pieces to the ejection area (40); a top and bottom edge opening member (g) consisting of end opening units (9); A valve plate application member (h) consisting of a valve plate unit (10) for storing, transporting and heat welding the valve plate to one end of the film cutting pieces; a folding member (i) for top and bottom folding (14, 15) of the film cutter; a cover sheet application member (j) consisting of a cover sheet unit (16) for storage, transport and thermal welding of the cover sheet; a stacking member (k) consisting of a stacker unit (31) for storing processed bags made of film cut pieces; and A main automation and control member (m) consisting of a control unit (41) for controlling the procedure of making bags (32) from film cut pieces. 8. The device of claim 1, wherein the stretcher unit (3) is a single station or a multi-station, wherein in the case of a multi-station stretcher unit, a plurality of side-by-side stations are provided, each station having a unique shaft to Facilitates the loading of multiple volumes. The device of claims 1 and 2, wherein the film perforating unit (5) is provided with at least one set of perforating rollers (6) comprising outwardly protruding in a cluster at 80 per square centimeter Pin fins scattered on the roller at a density of one to 90 pins. The device of claim 3, wherein the diameter of the needles is preferably in the range of 0.5 mm to 0.7 mm. 4. The device of claims 1 to 4, wherein the detection unit (4) comprises a transmitter (42) and a receiver capable of capturing an image of the thermoplastic film traveling through it and detecting any defects or changes in the color of the thermoplastic film transmitter unit (43), or any rupture or breakage is indicated by this transmitter/receiver unit. A device as claimed in claims 1 to 5, wherein the cutting member (d) consists of a cutting unit (7) operating according to a cold cutting principle. 6. The device of claims 1 to 6, wherein the edge opening member (g) consists of an end opening unit (9) in which the top and bottom ends (2A, 2B are opened using a rotating mechanism or a mechanism operating in a vertical plane) ), and wherein the sides are opened by a suction member or any kind of member such as a clamp configuration of two layers of an openable membrane before being subjected to the rotating mechanism, and wherein the opened layers of the membrane are subjected to a contoured structure, the contoured structure Rotate so that during movement in the Y direction, the bag is opened. The device of claims 1 to 7, wherein the valve disc application member (h) includes a valve disc unit (10), the valve disc unit (10) further comprising a valve disc unit (10) mounted on a free-rotating, continuous and smooth completion of the valve disc (36) supply a valve sheet roll (12) on a shaft, and cut the valve sheet (36) into valve sheet cutting pieces (11) of desired length and stick it to the film cutting piece (2) ) on the bottom end of a piece of welding unit (13). The device of claim 8, wherein the sheet welding unit (13) fixes the valve sheet (11) to the cutting piece (2) using means such as heat welding, hot melt gluing or by using ultrasonic methods. 9. The apparatus of claims 1 to 9, wherein the folding member (i) comprises a top folding unit (14) and a bottom folding unit (15) folded to form the bottoms of the square bottom pockets, and wherein the tops and bottom folding units (14, 15) are identical in construction and are placed at side A and side B, respectively. 10. The device of claims 1 to 10, wherein the cover sheet application member (j) comprises a cover sheet unit (16) which itself comprises a separate supply of cover sheets (37) to the folded film Two cover rolls (18) of the bottom and top ends of the cutting element (2). 11. The apparatus of claim 11, wherein the two cover slip rolls (18) are identical in construction and are mounted on a single frame. The device of claim 12, wherein the cover sheets (37) are cut into cover sheet cut pieces (17) to a desired length using a piece of welding unit (13) and adhered to the tops of the film cut pieces (2) and on the bottom. The device of claim 13, wherein the sheet welding unit (13) comprises a frame (19) on which a first idler roller (20), a second idler roller (21), and a third idler roller (22) are mounted thereon to provide tension to the sheet drawn from the rolls (12, 18); a pressure roller (23) also mounted on the frame (19) to apply tension at the first end (33) Pressure is applied to the sheets (36/37); a heated drum (27), and a master cutter roll (24) positioned at the second end (34) to cut the sheets (36/37) , wherein the master cutter roll (24) contains a set of blades or sharp knives, and wherein the hot drum (27) preheats the sheet cutting (11/17) so that in subsequent stages the sheet can be well Adhesive sticking on the film cutting part (2). 14. The device of claims 1 to 14, wherein a first sensor (25) is provided to sense the edge of the sheet (36/37) and correct for any lateral displacement of the sheet (36/37). The apparatus of claims 1 to 15, providing a second sensor (26) to sense any print marks present on the film and to cut the sheet to a predetermined length by sensing the print marks. As in the device of claim 14, a suction roller (28) is provided for sucking the valve sheet cutting piece (11) or the cover sheet cutting piece (17) to convey the same and place it on the cutting piece (2) ), wherein the suction cylinder (28) includes a plurality of micro-holes (38) through which suction is generated, and a support or pressure roller (29) is provided to provide a positive drive to the membrane (2). The apparatus of claim 17, wherein a heat gun (30) having a nozzle (39) is provided to inject a burst of air between the sheet (11/17) and the film cutting member (2) to create a heating zone, the The temperature of the heating zone is regulated by the amount of air to be injected by the heat gun (30). The device of claim 18, wherein the temperature of the heating zone is maintained just below the melting temperature of the film or better plastic, i.e. in the range of 80°C to 100°C or better 95°, The film (2) and sheet (11/17) do not melt but produce a good bond. The apparatus of claims 1 to 19, wherein an electronic control and automation system is used to control all operations in a synchronized manner, and the main control system has facilities for inputting the required control and program parameters through a human-machine interface. The apparatus of claims 1 to 19, wherein some of the stations may be manually operated. The device of claims 1 to 21, wherein the end opening unit (9) has a vertically positioned edge opening member provided with a rotating mechanism. An apparatus as claimed in claims 1 to 22, wherein the preparation member has a thermoplastic film perforation unit (5). The device of claims 1 to 24, wherein the preparation member has a positioning hole punching member and a thermoplastic film cleaning member. A method of manufacturing square bottom bags from thermoplastic films using the apparatus of claims 1 to 24, characterized in that the method comprises the following steps: a) stretching a thermoplastic film roll (1) from the stretcher unit (3); b) advancing the tested film through a perforated unit (5), wherein nano-preformed markings are produced on the film by a perforated roll (6); c) Detection of the perforated film in a detection unit (4), whereby the pre-perforated film is cut into cut pieces (2) by a cutting unit (7), so that a top end (2A) and a bottom end which are then opened are produced (2B); d) using the transfer unit (8) to transfer the cutting piece (2) from the X direction to the Y direction; e) opening the membrane (2) at the ends using an end opening unit (9); f) attaching the valve plate cutting piece (11) to the bottom end (2B); h) folding the top and bottom ends (2A, 2B) of the cutting piece (2) using top and bottom folding units (14, 15) respectively; i) Attaching the cover sheet cut (17) to the folded top and bottom ends (2A, 2B), thereby forming a pocket (32) with a square bottom end. A square bottom bag made of a tubular film, the bag having a parallelepiped bottom, characterized in that the bag is constructed entirely of heat-sealable thermoplastic material, wherein the bottom is formed and joined by non-contact heat welding to the side wall of the bag.

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