A device for producing a corner fold at a tubular bag body

Abstract

The invention relates to a device for producing a corner fold at a tubular bag body, which has a folding tool that can be inserted into the bottom opening of the bag body to produce the corner fold. In order to improve the production capacity and reliability of the device, a linear transport system with at least one mover is provided, wherein the folding tool is fixed to the at least one mover.

Description

Technical Field

[0001] The invention relates to a device for producing a corner fold at a tubular bag body, which has a folding tool which can be inserted into the bottom opening of the bag body to produce the corner fold. Background Art

[0002] Such a device is known, for example, from EP 2441 574 B1. According to this device, the bottom opening of the bag is formed by means of a surrounding expansion tool. EP 2441 574 B1 also describes that a second expansion tool can be provided independently of the first expansion tool. Then, an expansion tool is used for each bag, while the second expansion tool forms the bottom of the subsequent bag. Both tools are driven by servomotors and are subjected to strong acceleration forces.

[0003] However, due to the limited installation space, the number of expansion tools cannot be increased further. This limits the production capacity of the device, because both tools can only be operated at a maximum preset speed and acceleration. Summary of the invention

[0004] Therefore, the object of the present invention is to increase the production capacity and reliability of the device.

[0005] This object is achieved by the features of patent claim 1. Further preferred embodiments are contained in the dependent claims.

[0006] The basic idea of ​​the invention is to provide a linear transport system for guiding and controlling at least one folding tool. For example, a linear transport system is known from DE 102012204919 A1. The linear transport system comprises a base profile on which a plurality of movers can be guided and controlled according to the principle of a linear motor. By fastening the folding tool to one or more movers, the folding tool can be controlled precisely and highly dynamically. In principle, the number of movers and the number of folding tools fastened to the movers can be increased arbitrarily.

[0007] According to a preferred embodiment, a second mover is provided with a second folding tool for producing oppositely disposed corner folds of the bottom opening.

[0008] According to another preferred embodiment, a third mover with a third folding tool and a fourth mover with a fourth folding tool are provided for producing two subsequent opposite corner folds of the bag body.

[0009] According to a further preferred embodiment, a fifth mover is provided, to which a suction connection is fastened for opening the bottom opening.

[0010] According to another preferred embodiment, a sixth mover is provided, to which a pressing tool is fixed for pressing the generated corner fold. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Further details and advantages of the invention are described with reference to the accompanying drawings. In these drawings:

[0012] Figure 1 A linear transport system is shown, which has four movers and folding tools fastened to the movers,

[0013] Figure 2 A detailed view showing a folding tool, and

[0014] Figure 3 Shown is an overall view of the device according to the invention. DETAILED DESCRIPTION

[0015] Figure 1 A linear transport system 101 with four movers and folding tools fixed to the movers is shown. According to its basic structure, the linear transport system 101 consists of a base profile 102 with a guide rail 105, on which any number of movers 103 can be moved. The drive occurs via a coil package 104 integrated in the base profile 102, which is controlled by power electronics likewise integrated in the base profile 102. Each mover 103 has a transmitter flag (Geberfahne, or transmitter tab) 106, by means of which the position of the mover can be detected by the control electronics.

[0016] The basic profile 102 can be assembled from various components. Thus, the desired geometry, length and radius of the basic profile 102 are formed by the number and selection of components. Complex wiring is omitted because the power electronics and the travel measurement system are integrated in the basic profile.

[0017] Speeds of approximately 4 m / s can be reached without any problems with the movers with very high positioning accuracy. The movers can be accelerated, braked, positioned and synchronized. They can assume absolute and relative positions to one another. They can be grouped and accumulated or they can generate clamping forces while moving.

[0018] Figure 2 Detailed view of the folding tool 107 is shown. The folding tool consists of two holding arms 201 and 202, which are each fixed to one side of the mover 103. At the ends of the holding arms 201 and 202 there are respectively outwardly directed expansion plates 203 and 204, with which a corner fold can be produced in the bottom opening of the bag. In addition, as Figure 1Of course, the retaining arms 201 and 202 with the expansion plates 203 and 204 can also be fixed not to one mover but to two different movers. In this case, the retaining arms 201 and 202 can be constructed so that once the two movers are closely adjacent in position, the expansion plates 203 and 204 are located according to Figure 2 in the same relative position.

[0019] Figure 3 An overall view of the device according to the invention is shown. Figure 1 The linear transport system already described is installed in a fixed position in the device, while the conveyor belt 301 moves below it in the transport direction 302. The tubular bag 303 moves on the conveyor belt 301. The bag 303 is ensured not to slip relative to the conveyor belt 301 by a retaining device not further shown. For example, the retaining device can be realized by a corresponding magnet. Another possible solution is to provide holes in the conveyor belt 301 and to generate a vacuum under the conveyor belt 301, which sucks the bag 303 to the conveyor belt 301. For example, the bag 303 can be made of paper, plastic film or woven plastic belt or plastic thread.

[0020] In terms of transport direction, Figure 3 In front of the device shown in FIG. 3 there is a station with which the hose end of the bag body 303 is lifted from the conveyor belt 301 and folded vertically upwards. In order to produce a defined folding line, a so-called pre-folding strip 304 is provided here. The pre-folding strip 304 can be fixed in a fixed position relative to the conveyor belt 301, or it can be moved together with the conveyor belt 301. Which feasibility is installed in the device depends on various production parameters, such as the material of the bag body 303 and the transport speed of the conveyor belt 301.

[0021] After the bag 303 leaves the above-mentioned station, the vertically folded hose end passes through two oppositely placed suction connections 305 and 306, which open the two tube layers of the bag 303 so that the bottom opening 307 is formed in the manner shown. Depending on the application, the suction connections 305 and 306 can also be implemented as suction strips. In addition, the suction connections 305 and 306 can also be fixed in a fixed position relative to the conveyor belt 301, or can be moved together with the conveyor belt 301. Which feasibility scheme is installed in the device also depends on various production parameters here.

[0022] After the bottom opening 307 has been formed, the tube 303 enters the area of ​​the linear transport system 101. The mover 308 moves into the position shown at the appropriate moment, so that the folding tool 309 engages with the bottom opening 307 and produces a first corner fold. In a corresponding manner, the mover 310 moves into the engagement position to produce the opposite second corner fold of the bottom opening 307.

[0023] Then, movers 311 and 312 perform the same actions with reference to the subsequent tube, which were previously described for movers 308 and 310 with reference to tube 303. During this time, movers 308 and 310 are moved again into a waiting position to be able to perform actions on the subsequent tube at a given time.

[0024] according to Figure 3 , the mover is only used to move the folding tool. Of course, other actions can also be performed by the mover.

[0025] For example, suction connections may be fixed to the mover, which open the two tube layers of the bag before the corner fold is produced, so that a bottom opening is formed. For this purpose, a small suction turbine can be driven by the guide rollers of the mover, which generates negative pressure for the suction connection.

[0026] Likewise, a pressing tool can also be fixed to the mover, which pressing tool is pressed onto the produced corner fold after the corner fold has been produced, in order to produce a defined fold edge in the corner fold.

[0027] Reference numerals list

[0028] 101 Linear transport systems 102 Basic profile 103 Movers 104 Coil Pack 105 guide 106 Transmitter Flag 107 Folding tools 201 Holding arm 202 Holding arm 203 Expansion Plate 204 Expansion Plate 301 Conveyor Belt 302 Transport direction 303 Bag 304 Pre-folded slats 305 Suction connector 306 Suction connector 307 Bottom opening 308 Movers 309 Folding tools 310 Movers 311 Movers 312 Movers

Claims

1. A device for producing a corner fold at a tubular bag body, It has: a folding tool that can be inserted into the bottom opening of the bag body to produce a corner fold; A linear transport system having at least one mover, wherein the folding tool is fastened to the at least one mover, Features A second mover is provided, which has a second folding tool for producing oppositely disposed corner folds of the bottom opening, Therein, the at least one mover and the second mover can be guided and controlled according to the principle of a linear motor.

2. The device according to claim 1, wherein: A third mover with a third folding tool and a fourth mover with a fourth folding tool are provided for producing two oppositely disposed corner folds of the subsequent bag body.

3. The device according to any one of claims 1 to 2, wherein: A fifth mover is provided, to which a suction connection is fixed for opening the bottom opening.

4. The device according to any one of claims 1 to 3, wherein: A sixth mover is provided, to which a pressing tool is fixed for pressing the generated corner folded portion.

Images