Method for forming a hose comprising a flat web material as well as a hose formation device and a system for producing bags

Abstract

A method of forming a hose from a flat web material includes supplying the flat web material via a feeding device, folding the edges of the flat web material with at least one hose formation tool, with the edge sections subsequently overlapping, and connecting to each other parts of the overlapping edge sections, A target position of at least one edge is determined after the edges have been folded over, with the actual position of at least one edge being determined by a measuring device. In the event of a deviation of the actual position from the target position, the hose formation tool is moved, via an actuator, at least perpendicular relative to the direction of transportation of the flat web material.

Claims

1. A method of forming a hose from a flat web material, said method comprising: supplying the flat web material via feeding devices; folding over edges of the flat web material with at least one hose formation tool, with edge areas subsequently overlapping; connecting parts of overlapping sections with one another; determining a target position of at least one of the edges after the folding over of the edges; determining an actual position of the at least one of the edges with a measuring device; and in an event of a deviation of the actual position from the target position, to make a correction, moving the hose formation tool via an actuator at least perpendicular relative to a direction of transportation of the flat web material, the measuring device being moved simultaneously with the hose formation tool, such that, after the correction has been made, the actual position becomes a new target position.

2. The method according to claim 1, wherein the flat web material is a plastic web.

3. The method according to claim 2, wherein the plastic web is a coated plastic web.

4. The method according to claim 1, further comprising a step of providing the flat web material with perforation cuts prior to the hose formation.

5. The method according to claim 1, wherein the hose formation tool is arranged on a frame, and the frame is moved.

6. The method according to claim 1, wherein the measuring device is an ultrasound sensor or an electro-optic sensor.

7. The method according to claim 1, wherein the actual position of the edge is determined after the edges of the flat web material have been brought into the overlapped position.

8. The method according to claim 1, wherein the actual position of the edge is determined before the overlapping edges are connected to each other.

9. A hose formation device for forming a hose from a flat web material, said device comprising: at least one feeding device for supplying a flat web material; at least one hose formation tool for folding lateral edges of the flat web material, such that edge areas thereof are overlapping; at least one device for connecting parts of overlapping edges; a device for fixing a target position of at least one of the edges after the edges are folded over; a measuring device for determining an actual position of the at least one of the edges; and in an event of a deviation of the actual position from the target position, to make a correction, an actuator for moving the hose formation tool at least perpendicular relative to a direction of transportation of the flat web material, the measuring device being moved simultaneously with the hose formation tool, such that, after the correction has been made, the actual position becomes a new target position.

10. The hose formation device according to claim 9, wherein the feeding device includes a device for inserting perforation cuts into the flat web material.

11. The hose formation device according to claim 9, wherein the hose formation tool is arranged on a frame, and the frame is arranged so as to be displaceable.

12. The hose formation device in accordance with claim 11, further comprising guide devices which extend substantially perpendicular relative to the direction of transportation of the flat web material, and with the frame including sleds which are displaceable on the guide devices.

13. The hose formation device in accordance with claim 9, wherein the measuring device is an ultrasound sensor or an electro-optic sensor.

14. The hose formation device according to claim 9, wherein the measuring device is arranged, relative to the direction of transportation of the flat web material, downstream of the at least one hose formation tool.

15. The hose formation device according to claim 9, wherein the measuring device, relative to the direction of transportation of the flat web material, is arranged upstream of the device for connecting the parts of the overlapping edges.

16. The hose formation device according to claim 9, further comprising a control device, to which the actual position of the at least one edge can be transmitted by the measuring device, with which the actual position can be compared with the target position, and with which control signals can be transmitted to the actuator.

17. A system for making bags, said system comprising: a hose formation device for forming a hose from a flat web material, the hose formation device including at least one feeding device for supplying the flat web material, at least one hose, formation tool for folding lateral edges of the flat web material, such that edge areas thereof are overlapping, at least one device for connecting parts of overlapping edges, a device for fixing a target position of at least one of the edges after the edges are folded over, a measuring device for determining an actual position of the at least one of the edges, and in an event of a deviation of the actual position from the target position, to make a correction, an actuator for moving the hose formation tool at least perpendicular relative to a direction of transportation of the flat web material, the measuring device being moved simultaneously with the hose formation tool, and, after the correction has been made, the actual position becoming a new target position; a separating device for separating the hose into hose sections; and a bottom production device for providing a bottom at at least one end of the hose sections.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The individual figures show:

(2) FIG. 1 a side view of a hose formation device according to the invention

(3) FIG. 2 a top view of a hose formation device according to the invention

(4) FIG. 3 a view of the section A-A in FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(5) Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

(6) FIG. 1 shows a side view of a hose formation device 1 according to the invention. The hose machine comprising the hose formation device first comprises an unwinding device 2, in which a coil 3 of a flat web material 4 rotates in the direction of the arrow 5. The flat web material 4 is guided via a deflection roll 6, which represents a simple example of a feeding device of the flat web material 4 to the hose formation device 1.

(7) The deflection roll 6 is shown in this exemplary embodiment as a counter roll for the cutting roll 7, by which perforations can be inserted in the flat web material. The cutting roll 7 carries one or more perforating knives 8. The functions of the deflection roll 6, thus deflecting and providing counter pressure in the perforation process, are here only combined for reasons of better visibility, however in practice they are usually separated.

(8) The actual hose formation process begins already in the area between the deflection roll 6 and the hose formation device 1 by the edges 10 and 11 being guided upwards, thus in the direction z. Here, for example the compression roll 12, which holds the central part of the flat web material 4 at a fixed position in reference to the z-axis, and the guiding sheet 13 which from the outside applies lateral guiding forces for the flat web material are supportive. The compression roll 12 and the guide sheets 13 are examples for a plurality of potential hose formation tools, which may be used to provide the future hoses with the desired appearance. Additional examples for hose formation tools have already been provided in the general description of the invention.

(9) All of these hose formation tools are arranged at a frame 15, allowing the hose formation tools to be displaced in reference to the frame for adjustment and/or for preparing the production via suitable adjusting and fastening devices and to be fastened subsequently.

(10) It is easily discernible at the example of the guide sheets 13 that lateral forces are applied to the flat web material which may lead to a displacement of the hose in the z-direction and/or the y-direction.

(11) Additional hose formation tools are discernible in FIG. 3, which can be called lateral fold inserts 14. The lateral folds 18 that can be generated this way are preferably used for the production of certain bags or sacks because after their filling frequently almost a cuboid is formed, which offers advantages during storage and transportation. Particularly hoses with lateral edges can be produced in a particularly advantageous fashion on a device according to the invention using the method according to the invention because it particularly comprises hoses with lateral folds, primarily when they comprise staggered perforations, with the correct position of the edges after the hose formation being crucial, here.

(12) In the further progression of the hose formation process the edge areas of the flat web material are placed over top of each other such that already the cross-sectional contour represents a hose, which is still open in the longitudinal direction. This is clearly discernible in FIG. 3. The overlapping area 16 of the edge areas and/or the edges of the flat web material 4 is discernible in FIG. 2. The exterior folding edges of the hose can also be called lateral or exterior edges 17.

(13) In the further progression of the hose transportation in the direction z the sensor unit 20 follows, which is clearly discernible in FIG. 3. It includes a U-shaped profile 21 fastened at the frame 15, which carries the transmitter 22 and the receiver 23 of the sensor. The hose formation tools are arranged and embodied such that the edge 11 extends between the transmitter 22 and the receiver 23.

(14) A change in position of the edge 11 in the y-direction can therefore be detected by the sensor, with the sensor being implemented such that it can determine the extent of the change in position. The receiver transmits respective values or signals via a data line 24 to the control unit 25. Said control unit converts this information into control information which is sent via the control line 26 to the actuator 27.

(15) The actuator drive is arranged fixed, for example by way of a screw connection, to the floor of the facility, and via displacement elements it causes a shift of the frame in the y-direction. The actuator may for example be a rotating electric motor, which acts via transmission elements 28, such as a spindle-spindle nut arrangement or a rack and pinion arrangement, upon the frame 15. A linear drive, for example a linear electric motor, is possible and would also be operational without transmission elements.

(16) The frame 15 rests on the sled 30, which in turn rest on the guide rails 31 and are displaceable along thereof. The contact between the sled and the guide rails can be formed here by sliding or roll elements.

(17) For the completion of the hose 9, here another permanent connection of the edge areas of the already deformed flat web material 4 is necessary, which already overlap in the overlapping area 16. For this purpose an extrusion device 32 is provided, by which molten plastic can be applied in the overlapping area 16 between the edge sections. With a compression roll, following in the x-direction but not shown here, the overlapping area is then compressed such that after the setting of the plastic here a solid connection results. However, many other types of connections are also possible.

(18) The now finished hose 9 is generally deformed in the winding device 33 into a hose coil 34 (see FIG. 1), which then can be fed to a bagging machine.

(19) However it is also possible that a further processing machine directly follows the hose machine, without first requiring hose coils to be formed.

(20) The invention being thus described, it will be apparent that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be recognized by one skilled, in the art are intended to be included within the scope of the following claims.

LIST OF REFERENCE CHARACTERS

(21) TABLE-US-00001 1 Hose formation device 2 Winding device 2 3 Coil 4 Flat web material 5 Arrow (direction of rotation of the coil 3) 6 Deflecting roll 7 Cutting roll 8 Perforation roll 9 Hose 10 Edge 11 Edge 12 Compression roll 13 Guide sheet 14 Lateral fold insert 15 Frame 16 Overlapping area 17 Lateral or exterior edges 18 Lateral folds 19 20 Sensor unit 21 U-shaped profile 22 Transmitter 23 Receiver 24 Data line 25 Control unit 26 Control unit 27 Actuator 28 Transmission elements 29 30 Sled 31 Guide rail 32 Extrusion device 33 Winding device 34 Hose coil