CZ20021318A3 - Process for producing hose-like bags and apparatus for making the same - Google Patents

Abstract

A strip of a flat packaging material (1) is cut by a knife (8) to two separated strips (1.1, 1.2). each strip (1.1, 1.2) passes over its own leading edge (2.1, 2.2) into an assigned molding device (3.1, 3.2), where it is molded around a filling tube (7.1, 7.2) into the form of a hose (14.1, 14.2) the longitudinal overlapping parts of which are sealed in an elongate sealing apparatus (5.1, 5.2). In addition, the controlled strip (1.2) is guided over a straightening roller (11) fastened on a swing arm (18). The swing of the arm (18) corresponds to the slip or advance of the controlled strip (1.2) relative to a control strip (1.1). The direction and magnitude of the swing is converted to an electric signal, which accelerates or decelerates the movement of a second feeding device (4.2) relative to a first feeding device (4.1) and adjusts the feed of both the longitudinally sealed hoses (14.1, 14.2) such that both the hoses (14.1, 14.2) are always in the same position at the spot of transverse sealing and separating jaws (6) and before transverse sealing of the hose bag pair. From one roll of the packaging material (1) that is moving continuously, pair of hose-like bags are simultaneously made.

Description

BACKGROUND OF THE INVENTION The present invention relates to a method for continuously forming two hose bags from a single roll of packaging material, filling them and closing the filled bags, and an apparatus for performing the method.

BACKGROUND OF THE INVENTION

Methods and apparatus are known for forming tubular bags from wrapping material that is rolled into the tubing longitudinally and transversely. For transverse welding, the bag filled with the packaged goods is closed and at the same time the bottom of the next bag is formed before it is filled. Filled bags are separated after closing. There are also known devices that create and pack two hose bags. EP-A-122477 discloses an arrangement in which a pair of identical devices for parallel forming bag bags is provided. Both devices work in a cycle of one bag. The transversal welding devices grasp the hose bags in the upper position and detach the closed hose bags in the lower position. In particular, it protects the displacement device for transversally welding the hose bags from one position to another and back. DE Patent No. 19601598 discloses a similar device which creates, fills and closes two parallel bags at the same time. It protects an arrangement in which there are two pairs of clamping jaws per bag and one pair of welding jaws in the space between them. The horizontal movement of the clamping jaws of both bags is simultaneous. The horizontal movement of the welding jaws is completely independent of the movement of the jaws. DE-A-19627892 discloses a packaging device in which the film is cut and fed to a device in which hoses are formed and tubing bags are formed from hoses. They fill and close. The invention defines a welding jaw drive perpendicular to the direction of movement of the film. It protects the articulated arrangement of the lever system where the pivot points of the levers are located on the movable elements. The required drives are provided by linear motors. The whole system is managed by a computer.

A disadvantage of known methods and apparatus for forming tubular bags in which the wrapping material moves in an intermittent cycle is that it does not allow overlapping times for the wrapping material movement and the welding time. It does not allow maximum utilization of the duty cycle time. The welding time, which is important for some types of packaging material, cannot be set. It is fixed by the length of the bag and the number of bars of the machine. The length of the longitudinal jaw, which is fixed, limits the maximum length of the bags, and in the case of short bags, the welding is repeated to the already welded region of the longitudinal weld. The arrangement with the lever system states that it also allows a continuous way of working. A method and apparatus for making tubular bags in parallel, ensuring their desired length and proper placement of the possible printing on the bags in a continuous process of their manufacture are not disclosed in the prior art.

SUMMARY OF THE INVENTION

These drawbacks are largely overcome by the method of forming tubular bags, in which the flat wrapping material is first cut longitudinally into two parallel strips of wrapping material. Each strip of packaging material is formed into a separate hose with overlapped edges. Each hose is closed longitudinally with a longitudinal seam and packaged goods are inserted into each hose. Both hoses are provided with a transverse seam that forms the bottom of the two adjacent upper hose bags and closes the two adjacent lower hose bags that separate from the upper hose bags. SUMMARY OF THE INVENTION The principle of the invention is that the formation of hoses, the formation of hose bags, the insertion of goods into the hose bags, the closure of filled hose bags and the separation of filled and closed pairs of hose bags proceed with continuous movement of the packaging material. Continuous movement of the wrapping material is provided by the separate movement of each parallel strip of wrapping material, one of which is the driving band and the other is the driving band. The longitudinal displacement of the two moving belts of the wrapping material is continuously detected and the slip or lead of the controlled wrapping material strip relative to the wrapper control strip is evaluated. Depending on the value of the detected advance or slip, a corresponding acceleration or deceleration of the sliding movement of the controlled web of packaging material is produced. Thus, when forming hoses with overlapping edges, simultaneously welding the side seam on each hose, closing and separating the filled hose bags and forming the bottom of the subsequent hose bags with a transverse seam, two hose bags are simultaneously formed.

The apparatus for carrying out this method comprises a knife for cutting the packaging material into two belts, one of which is a control material wrapper and the other is a controlled material wrapper. It further includes position and mark sensing sensors, a forming device for forming overlapped tubing from each wrapping web, longitudinal welders for forming a longitudinal seam on the overlapped tubing, and transverse welding and separating jaws for closing and separating filled tubular bags and forming The invention is based on the fact that two adjustable guide edges are provided behind the knife in the direction of movement of the packaging material for guiding each strip of packaging material to its associated forming device. Each guide edge is provided with a separate drive to adjust its position, and its own position sensor to sense its position. Behind each leading edge is an optical sensor for sensing centering marks located on each wrapping web and an edge sensor for detecting the edge of the wrapping web. There is an alignment roller between the second guide edge and the second optical sensor. The alignment roller is mounted on the swing arm. The swing arm is equipped with a leveling position sensor to monitor the swing of the arm. The alignment position sensor is electronically connected to the second driving device of the second shifting device. The controlled web of wrapping material abuts the second leading edge and the alignment roller.

An advantage of the method and apparatus of the invention is that it provides for the simultaneous formation of pairs of tubing bags, their filling, sealing and separating of filled tubing bags while continuously moving the packaging material from one foil. It eliminates unwanted unproductive operations that are necessary in the clock mode. Since the longitudinal welding, filling, transverse welding and separating of the hose bags take place during the continuous movement of the packaging material, the maximum utilization of the working cycle time is achieved in this way. Productivity is considerably higher than the intermittent cycle method. The device allows easy and quick adjustment for different lengths of hose bags and adjustment of welding time. It allows to create pairs of hose bags of the same width and pairs of hose bags of uneven width _y by changing the position of the knife and adjusting the forming device.

Overview of the drawings

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be explained in more detail with reference to the drawing, in which: FIG. 1 shows an overall diagram of the apparatus in a front perspective view, FIG. 2 shows a plan view of the wrapping material in longitudinal and transverse direction; provide strip control, hose formation, displacement, longitudinal welding, filling, transverse welding, and separation of filled hose bags in front view and FIG. 4 of a packaging material hose and a first filling tube in cross section passing through a horizontal plane above the displacement device and longitudinal welding machine.

DETAILED DESCRIPTION OF THE INVENTION

In a continuous process for the simultaneous production, filling, sealing and separation of two parallel hose bags, the continuous wrapping material 1, which is continuously unwound from a roll, is first slit lengthwise into two parallel straps of wrapping material, one of which is a control strip 1,1 and the second is a controlled belt 1,2. If it is desired that the two simultaneously formed tubing bags be of the same width, then the foil of the wrapping material (1) is cut into two strips 1.1, 1.2 of the same width. If it is desired that the two tubular bags formed at the same time be of different widths, then the packaging material sheet 1 is cut into two strips 1.1, 1.2 of different widths. Each strip 1.1, 1.2 of the wrapping material 1 is simultaneously formed into a separate hose with overlapped edges. At the same time, each hose is closed longitudinally with a longitudinal seam. Both hoses are also fitted with a transverse seam. This creates, on the one hand, the bottoms of the two adjacent upper tubular bags which are ready for insertion of the packaged goods. At the same time, two adjacent lower hose bags are closed which are filled with the packaged goods and which are separated from the upper hose bags after closing. All these operations take place with the continuous movement of the wrapping material 1. The continuous movement of the wrapping material 1 is ensured by the separate movement of each hose. In order to ensure that both hoses are at the same desired location before transverse welding, the longitudinal displacement of the two moving separate belts 1.1 and 1.2 is continuously measured. The slip or lead of the controlled belt 1.2 relative to the control belt 1.1 is continuously evaluated. According to the value of the detected advance or slip of the controlled belt 1.2 relative to the control belt 1.1, a corresponding acceleration or deceleration of the sliding movement of the hose formed from the controlled belt 1,2 is produced. This ensures that two hose bags are simultaneously formed in the same relative position.

In the device for forming a pair of hose bags with continuous movement of packaging material, the flat packaging material 1, which must be heat-sealable on at least one side, is placed on a roll at the rear of the device (Fig. 1). The packaging material 1 may be unprinted or is provided with a so-called endless print, or is printed with centering marks 16.1 and 16.2 (Fig. 2). The printing with the centering marks 16.1 and 16.2 is used when each hose bag requires that the printing on the bag always be in the same position. In the upper part of the apparatus there is a knife 8 for dividing one strip of flat packaging material 1 into two separate belts, one of which is a control strip 1.1 and the other is a controlled strip 1.2. The blade 8 is adjustable in the transverse direction to precisely adjust the desired belt widths 1.1, 1.2. In the exemplary embodiment, both belts are 1.1

1.2 of the same width. For guiding the two belts 1.1 and 1.2 of the wrapping material 1 into the corresponding forming devices 3.1 and 3/2, in which the hoses 14.1 and 2 are formed.

14.2. there are two guide edges 2.1 and 2.2 (Fig. 3) which have the shape of rollers. They are located on the top of the device. The first guide edge 2.1 serves to guide the control strip 1.1 to the first forming device 3.1. The second guide edge 2.2 serves to guide the controlled belt 1.2 into the second forming device 3.2. Under the action of the leading edges 2.1 and 2.2, the axis of each strip 1.1 and 1.2 is displaced from the original axis of each strip 1.1 and 1.2 by cutting with a knife 8 a distance x (FIG. 2). After displacement by the distance x, the axis of each strip 1,1 and 1.2 is shifted from the original axis to such an extent that it lies in a vertical plane in which the axis of the corresponding forming device 3.1 and 3.2 lies. The angle of rotation of each guide edge 2.1 and 2.2 can be changed and the change is made if the width of the hose bag is to be changed or if the longitudinal weld overlap is required. Changing the angle of rotation of the guide edges 2.1 and 2.2 is provided by the associated drives 12.1 and 12.2. The position of the guide edges 2.1 and 2.2 is sensed by the associated position sensors 13.1 and 13.2 (Fig. 3). When changing the width of the hose bag, the guide edges 2.1 and 2.2 shall be rotated to the desired position so that the axis of each strip 1.1 and 1,2, from which the hose of the changed width is to be made, passes through the vertical plane in which the axis of the corresponding forming device lies. 3,1 a

3.2. An edge sensor 15.1 is placed in front of each forming device 3.1 and 3.2

15.2 for detecting the edge of each strip 1.1 and 1.2 of the wrapping material T By gently turning the leading edges 2,1 and 2.2, the two stripes 1.1 and 1.2 are constantly maintained in the same position relative to the corresponding forming apparatuses 3,1 and 3/2. In this way, the same overlap y (FIG. 4) of the longitudinal weld region is maintained. Under each shaping device 3.1 and 3.2 there is a filling tube assigned to it 7.1 and 7.2 (Fig. 3). On each filling tube 7.1 a

7.2. A corresponding longitudinal welding machine 5.1 and 5.2 is placed. which serves to form a longitudinal weld on the corresponding strip 1.1 and 1.2 while simultaneously moving it, after forming it into a hose 14.1, 14.2 with overlapped edges. On each feed tube 7.1 and 7.2 opposite the longitudinal welding machine 5.1 and 5.2 there is a displacement device 4.1 and 4.2 made of vacuum feed belts. The displacement devices 4.1 and 4.2 serve to move the corresponding strip 1.1 and 1.2 formed into the hoses 14,1, 14.2 with overlapping edges. This is both the independent movement of the two belts 1.1 and 1.2 and at the same time the synchronous guiding of the shaped and longitudinally welded hoses 14.1, 14.2 into the transverse welding and separating jaws 6. The transverse welding and separating jaws 6 serve for transverse welding. bags and the bottom of the two subsequent hose bags are formed. It also serves to simultaneously separate two filled and closed tubing bags from two tubing bags prior to filling. If the packaging material 1 does not have a print or is provided with a so-called endless print, then both hoses 14.1, 14.2 are synchronized to the transverse welding and separating jaws 6 by means of the alignment roller 11. edge 2.2, and in front of the second forming device 7.2. The alignment roller 11 is mounted on a swivel arm 18 which is connected to the alignment position sensor 10. The alignment position sensor W, which is electronically connected to the second drive device 17.2, the second shifting device 4.2, serves to sense the position of the alignment roller H or to sense. the pivoting position of the pivot arm 18 on which the alignment roller 11 is located. If the packaging material 1 is printed, there is a centering mark 16.1 and 16.2 on each bag. The centering marks 16.1 and 16.2 are used to synchronize the input of the two strips 1.1 and 1.2 to the transverse welding and separating jaws 6. The first optical sensor 9.1 and the second optical sensor 9.2 are used to synchronize the corresponding centering marks 16.1 and 16.2.

The device works as follows. The foil of the web-shaped wrapping material 1 is unwound from a roll, and is divided into two parts by a knife 8, i.e. a control belt 1.1 and a control belt 1.2. Every belt

1.1 and 1.2 pass over their associated leading edge 2,1 and 2.2, thereby moving away from each other and moving their axes to a vertical plane in which the axes of their respective forming devices 3.1 and 3.2 lie. The edge position of each strip 1.1 and 1.2 is sensed by the associated edge sensors 15.1 and 15.2. By gently turning the edges, the two strips 1.1 and 1.2 are kept in the same position relative to their forming apparatuses 3.1 and 3.2. This ensures the same overlap in the area in which, after the two bands 1.1 and 1.2 have been formed into a hose 4.1, 4.2, a longitudinal muscle is formed. In each forming device 3,1 and 3.2, each band 11 and 12 of the packaging material 1 is shaped hoses 4.1, 4.2 with overlapped edges around the filling tube 7.1a 7.2 The shifting device 4.1 and 4.2 pushes the packaging material 1 shaped in the shape of a hose 4.1, 4.2 with the overlapped edges continuously downwards. Depending on the pivoting position of the swing arm 18, the alignment position sensor 10 evaluates whether the controlled web 12 of the wrapping material 1 is slipping or ahead of the control belt 11. Accordingly, the alignment position sensor 10 sends signals to the second drive device 17.2 to accelerate or slow the movement The longitudinal welding machines 5.1 and 5.2 continuously weld longitudinally the packaging material 1 shaped in the form of a hose 4.1, 4.2 at the overlapping edges. If the packaging material 1 does not have a print or is provided with a so-called endless print, the guidance of the two hoses 4.1 and 4.2 into the transverse welding and separating jaws 6 is synchronized by the electronic coupling between the alignment position sensor 10 and the second displacement device 4.2. If the packaging material I is printed with centering marks 16.1 and 16.2, the synchronization of the guidance to the transverse welding jaws 6 is ensured by the marker sensors 9.1, 9.2, in conjunction with the displacement device 4.1, 42. The transverse welding jaws 6 create transverse welds simultaneously on both On the one hand, both filled hose bags are closed by a transverse weld and, on the other hand, the bottom of the next pair of hose bags is formed before filling. At the same time, the pairs of filled and closed hose bags are separated from the pair of bottomed hose bags that are ready to be filled with the goods to be packaged and which are fed into the hose bags via the corresponding filling tube 7.1 and 72. hose bags with the same length, desired width, or with the exact placement of the print on both hose bags.

Industrial applicability

The invention is used in the packaging technique in the simultaneous and continuous production of two tubular bags and the packaging of products in these tubular bags.

Claims (3)

PATENT CLAIMS A method for forming hose bags, in which one sheet of flat packaging material (1) is first cut lengthwise into two parallel strips (1.1, 1.2) of packaging material (1), each of which forms a separate hose (14.1, 14.2) with overlapped edges, which are longitudinally closed with a longitudinal seam, packed goods are inserted into each hose (14.1, 14.2), whereupon both hoses (14.1, 14.2) are provided with a transverse seam which forms the bottom of two adjacent upper hose bags and closes two adjacent lower hose bags separating from the upper hose bags, characterized in that forming the hose bags by forming two strips (1.1, 1.2) of the packaging material (1) into hoses (14.1, 14.2) with overlapping edges, closing the hoses (14.1, 14.2) with a longitudinal seam, loading goods, closing the pairs of hose bags and separating filled and closed pairs of hose bags takes place with continuous movement of the packaging material (1). 1.1, 1.2) of the packaging material (1), in which the mutual longitudinal displacement of the two moving belts (1.1, 1.2) of the packaging material (1) is continuously detected, the slippage or advance of the controlled web (1.2) of the packaging material (1) relative to the control a strip (1.1) of the wrapping material (1) and, depending on the value of the detected advance or slip, a corresponding acceleration or deceleration of the sliding movement of the controlled strip (1.2) of the wrapping material (1) is produced by forming the hoses (4.1, </ 4.2) , by welding the side seam on each hose (14.1, 14.2) and by closing the bottom with a transverse seam, two hose bags are formed simultaneously. Apparatus for carrying out the method according to claim 1, comprising a knife (8) for cutting the wrapping material (1) into two belts (1.1, 1.2), one of which is a control strip (1.1) of the wrapping material (1) and the other is a controlled strip (1.2) packaging material (1), sensors (9.1, 9.2) (13.1, 13.2) for position and mark sensing, forming device (3.1, 3.2) for forming hoses (4.1,44.2) with overlapping edges from each strip (1.1, 1.2) of wrapping material (1), longitudinal welding machines (5.1, 5.2) for making longitudinal seam on each hose - $ 4.1,44.2) with overlapping edges and transverse welding and separating jaws (6) for closing and separating filled tubular bags and for forming the bottom of subsequent tubular bags, characterized in that two adjustable guide edges (1) are provided behind the knife (8) in the direction of travel of the packaging material (1) 2.1, 2.2) for guiding each strip (1.1, 1.2) of the packaging material (1) to its associated forming device (3.1, 3,2), each leading edge (2.1, 2.2) is provided with a separate drive (12.1, 12.2) for adjusting its position, and its own position sensor (13.1, 13.2) to sense its position, behind each guide edge (2.1, 2.2) is provided optical sensor (9.1, 9.2) centering marks (16.1, 16.2) disposed on each strip (1.1, 1.2) of the wrapping material (1) and an edge sensor (15.1, 15.2) to sense the edge of the strip (1.1, 1.2) of the wrapping material (1), 2.2) and the second optical sensor (9.2) is an alignment roller (11) mounted on a swivel arm (18) provided with an alignment position sensor (10) for monitoring the swivel arm (18), wherein the © / alignment position sensor (10) is electronically connected to the second driving device (17.2) of the second shifting device (4.2) and the controlled web (1.2) of the packaging material (1) abuts the second leading edge (2.2) and the alignment roller (11).