WO2016071261A1

WO2016071261A1 - Method and device for producing bags from tubular bag bodies

Info

Publication number: WO2016071261A1
Application number: PCT/EP2015/075409
Authority: WO
Inventors: Herbert Fürst
Original assignee: Starlinger & Co Gesellschaft M.B.H.
Priority date: 2014-11-04
Filing date: 2015-11-02
Publication date: 2016-05-12
Also published as: BR112017007870B1; CN110154448A; CN107073862B; BR112017007870A2; EP3017940A1; CN110154448B; CN107073862A; EP3017940B1

Abstract

A device (1) for producing bags from tubular bag bodies (10) comprises a transport device (2) which transports the bag bodies in a flat manner transversely to the longitudinal extent (L) thereof in a transporting direction (T) at a transport rate (V). While being transported, the bag bodies pass through processing stations (30, 40, 50, 60, 70, 80) by way of which at least one end region (13) of each bag body is formed into a cross bottom and optionally a cover sheet (19) is applied to the cross bottom. A transfer device (4) moves the bag bodies (10) to be transported by the transport device at a transfer rate (U), with respect to bag bodies conveyed at a transport rate (V), by a feeding distance (Δy) in the transporting direction (T) and then transfers them to the transport device (2). The feeding distance (Δy) is selected such that successive bag bodies overlap one another, wherein the overlapping width preferably corresponds to once or twice the height (h) of the triangular corner fold (14) which is produced when the bottom side flaps (15, 16) are folded over.

Description

Method and apparatus for making bags of tubular

bag bodies

The invention relates to a method and an apparatus for producing sacks of tubular bag bodies, wherein the bag body preferably made of a fabric of plastic tapes or a nonwoven plastic material (eg plastic fleece) or a composite of the fabric of plastic tapes and the nonwoven plastic material or with a a plastic film connected to a network structure are produced, wherein the material optionally at least one side with at least one plastic layer and / or at least one plastic film, eg an OPP film is coated. The bag bodies are transported on a transport device lying flat transversely to its longitudinal extent at a transport speed in a transport direction, wherein the bag body undergo processing stations during their transport, with which at least one end portion of each bag body formed into a cross bottom and optionally a cover sheet is applied to the cross bottom.

Chest bags, also called cross-bottom bags, are sacks of parallelepiped shape, which are manufactured in bag making machines by providing tubular bag bodies whose open end portions are folded into cross bottoms. The bag bodies are guided lying flat through the clothing plant, so that two layers of the tubular bag body abut each other. For bottom formation, the two layers are separated at the end portions of the tubular bag body, and one of the two layers is folded over as a side flap by 180 ° to itself, creating an open bottom, in which the other layer forms a second side flap. By folding a layer at the end of the tubular bag body arises at the front and rear of this end portion each have a triangular corner impact. This process is also known as "mounting." In a further processing sequence, valve blades can be inserted (for producing "box valve bags" that can be filled with filler through the valve) and the final floor configuration is made by overlapping the bottom side doors. The overlapping bottom side flaps are glued together or thermally welded depending on the material of the bag body. Alternatively or additionally, bottom cover sheets can be placed on the overlapped bottom side flaps and glued or welded to them. Such a Sackkonfektionsanlage is described in the patent AT 408 427 B. The throughput of sack confectioning equipment is significantly dependent on the transport speed at which the hose sections to be assembled are transported through the clothing plant. As a disadvantage of the known from the patent AT 408 427 B Sackkonfektionsanlage the intermittent operation of this system has been found that limits the throughput of processed to bag bodies. The time required for cyclic mounting of the floors, including the required fixation of the raised floors, may even be an upper limit to the performance of the entire sack making apparatus.

This disadvantage was overcome by the device disclosed in EP 2 441 574 B1 for forming open trays on bag bodies, which enables a continuous conveying of the bag bodies, which led to an increase in transport speed and productivity.

The transport speed of bag bodies in Sackkonfektionieranlagen could be further increased by the invention described in EP 2 711 166 AI, with which the clock frequency of a workpiece holder in the transfer area of bag bodies was increased by the longitudinal transport to the transverse transport.

Meanwhile, with the increase of the transport speed to the limits of the performance of along the transport path of the bag body arranged means for forming the cross bottoms, in particular hot air welding devices for attaching bottom cover sheets and / or valves to the bag bodies, encountered. Therefore, an increase in the throughput of Sackkonfektionieranlagen can not be achieved by a further increase in the transport speed of the bag body.

Another Sackkonfektionieranlage is disclosed in DE 12 16 196 B. In this document, the possibility is raised to reduce the workpiece speed after the removal of the workpieces from the longitudinal conveyor region, which would also reduce the distance of the workpieces from each other at the same time. However, such an embodiment is discarded as being impractical because one would refrain from realizing it because of the complexity and expense of the device.

In clothing plants for box bags or box valve bags according to the prior art tubular bag bodies are fed transversely to its longitudinal extension of a continuously moving transport device and go through their transport different processing stations, such as a bottom opening device. Such a clothing plant is shown schematically in FIG. When transporting the bag body in the transverse direction of the repeat (x), which is the distance between the front longitudinal edges or the rear longitudinal edges of two successive bag body (10), usually set fixed and remains constant even when processing differently wide (b) tubular bag bodies , Thus, the throughput of bag bodies by the Sackkonfektionieranlage essentially of the transport speed (V) of the transported bag body and the repeat depends. Especially with bag bodies of small width (b) resulting from the fixed repeat (x) relatively large distances (y) between the bag bodies (10), which prevent the transport potential of the Sackkonfektionieranlagen is fully utilized.

A further disadvantage of the fixed set repeat is that hot air welders needed for attaching the ground cover sheets run empty between the successive bag bodies, whereby considerable energy in the form of hot air is released to the environment unused as a shutdown and Restarting the hot air welding devices between successive sacks for technical process reasons is not possible.

It is therefore an object of the present invention to increase the throughput of bag bodies in Sackkonfektionieranlagen without increasing the transport speed of the bag body.

This object is achieved by an apparatus and a method for producing sacks of tubular bag bodies with the features of claims 1 and 11, respectively. Advantageous embodiments of the invention are set forth in the subclaims and the description below.

The device according to the invention and the method according to the invention for producing sacks from tubular bag bodies are particularly suitable for processing bag bodies which are made of a fabric made of plastic tapes or a nonwoven plastic material (eg plastic fleece) or a composite of the fabric made of plastic tapes and the nonwoven fabric. Plastic material or a plastic film connected to a network structure are made, wherein the material is optionally coated on at least one side with at least one plastic layer and / or at least one plastic film, such as an OPP film. The bag bodies are transported lying flat transverse to their longitudinal extent at a transport speed in a transport direction, wherein formed on the bag bodies during their transport at least one end portion to a cross bottom and optionally a cover sheet is applied to the cross bottom.

To be transported bag body are moved by at least one transfer device in relation to transported at transport speed bag body by a feed distance in the transport direction and then moved at the transport speed, wherein the movement of the bag body on the feed path at least partially takes place at a transfer speed which is greater than the transport speed. By this measure, the length of the repeat is adjusted and can be adjusted to a predefined distance between adjacent bag bodies by the feed distance is calculated and controlled in dependence on the width of the bag body so that the predefined distance between successive bag bodies or between the cover sheets sequentially Sack body results.

A particularly good utilization of processing stations, such as a hot air welding station is achieved when the feed distance is selected so that successive bag bodies overlap, preferably the overlap width corresponds to the single or double height of the triangular corner impact, which results when turning the bottom side flaps. In the latter case, at least one of the successive bag bodies, a longitudinal section facing the other bag body, which has a width which corresponds to the height of the corner impact, is folded over.

In one embodiment of the invention, the transfer device comprises a first transport device and a second transport device, the bag body move lying transversely to its longitudinal extent in the transport direction, the first transport device upstream of the second transport device is arranged and the transport speed of the first transport device is higher than the transport speed the second transport device. In this embodiment, an overlapping arrangement of the bag body can be achieved with little equipment.

The device according to the invention for producing sacks of tubular bag bodies has proved to be particularly efficient when the processing stations comprise a bottom opening station and the transfer device is arranged downstream of the bottom opening station. So that the device according to the invention can be operated automatically, the width of the bag body is detected by a sensor.

For a gentle treatment of the bag body and for an exact recording of the bag body and transfer to the transport device, the speed with which bag body can be moved on the feed line, be controlled according to a speed profile. The speed profile includes accelerating to the transfer speed and, after a length of time dependent on the length of the feed distance, braking to the transport speed.

With the device according to the invention, the bag making can be further improved and automated even higher, if based on the detected bag width and the predefined distance of successive bag body, the cover sheet nominal position and the desired length of the cover sheets and optionally calculates the desired valve leaf position of valve leaves and based on this information cover sheets are cut to the desired length and applied to the bag body when they have reached the cover sheet set position, and optionally the valve sheets are applied to the bag body when they have reached the desired valve leaf position ,

For reliable handling, the transfer device preferably has holding means for gripping, holding and releasing the bag body, wherein the holding means can be designed as mechanical grippers and / or vacuum cups. A controller controls the times at which the holding means grasp and release the bag bodies. If at least two holding means are provided which are movable independently of one another, it is possible by means of suitable control to align misaligned bag bodies by different movements of the holding means. Misalignments may e.g. caused when cutting the bag body.

The invention will now be described in more detail by means of embodiments with reference to the drawings.

Fig. 1 shows a schematic representation of a Sackkonfektionieranlage according to the

Principles of the invention.

FIG. 2 shows a perspective view of a bag making machine according to an embodiment of the invention. FIG. Figures 3 and 4 show plan views of bag bodies during their transport on the transport device, showing the distances between successive ones

Illustrate bag bodies.

Figures 5 and 6 show plan views of bag bodies during their transport on the transport device, showing the distances between successive ones

Illustrate bag bodies according to the invention.

Fig. 7 shows a schematic representation of another embodiment of a

Sack making plant according to the principles of the invention.

Fig. 8 shows schematically a transport device of a Sackkonfektionieranlage according to the prior art.

With reference to FIGS. 1 and 2, the principle of the device 1 according to the invention and of the method according to the invention for producing sacks of tubular bag bodies 10 will now be explained and described with reference to an exemplary embodiment. The device 1 comprises a transport device 2, which transports the bag body 10 lying flat transversely to its longitudinal extension L at a transport speed V in a transport direction T. The bag bodies have a front side edge 11 and a rear side edge 12, between which the width b is measured. Guide rails 3 hold the bag body 10 in the correct position on the transport device. The bag bodies 10 are made of a stretched plastic tape fabric or a nonwoven plastic material (eg, nonwoven fabric) or a composite of the fabric of plastic tape and the nonwoven plastic material or a plastic film bonded to a net structure and are preferably provided with a coating of a polymer , Composites may also include plastic films, paper sheets or metal foils. The coating preferably has a layer of an OPP film, furthermore printing layers, etc.

In the embodiment of FIG. 2, a hose 10a is fed from a storage device or an inline hose-forming machine, not shown, to a cross-cutting device 8 which cuts tubular bag bodies 10 from the hose 10a and feeds them to the transfer device 4 described in detail below.

During their transport on the transport device 2, the bag body 10 through processing stations with which at least one end portion 13 of each bag body 10 is formed into a cross bottom and a cover sheet 19 is applied to the cross bottom. In the described embodiment, the processing stations described below are formed. In other embodiments of the invention However, not all of these processing stations realized, or there may be other processing stations (quality inspection, printing device, etc.) are provided.

The processing stations are shown symbolically in Fig. 1 for reasons of clarity only by arrows. A folding station 30 serves to fold the end portions 13 of the bag body 10 from the flat state about the guide rails 3 upwards. A bottom opening station 40 is used to pull the two folded-up layers of the end portions 13 of the bag body 10 from each other and fold in opposite directions by 90 °, creating an open bottom 17 is formed, which has two side flaps 15, 16, of which a side flap 16 to 180 ° is folded back onto the wall of the bag body 10. By folding over the side flaps 15, 16 is formed at the front and rear of the open bottom 17 each have a triangular Eckeinschlag 14. In a valve sheet insertion station 50, a valve sheet 18 is placed on the open bottom 17 of the bag body 10 and optionally by gluing or thermal welding fixed. Thereafter, in a bottom forming station 60, the final cross-bottom configuration is made by wrapping the bottom side flaps 15, 16, while the triangular envelopes 14 are reduced in size at the front and rear bottom end portions, but are retained in their triangular shape. Since the side flaps 15, 16 are folded over at mutually parallel folding edges, the triangular envelopes have the shape of an isosceles triangle whose hypotenuse extends between end points of the folded edges. The embossed bottom side flaps 15, 16 are glued together depending on the material of the bag body or thermally welded when they overlap each other. However, there are also embodiments of bags in which the bottom side flaps 15, 16 do not overlap each other. In the illustrated embodiment, a cover sheet applicator station 70 for applying a bottom cover sheet 19 to the embossed bottom side flaps 15, 16 and a hot air welding station 80 for fixing the bottom cover sheet 19 on the embossed bottom side flaps 15, 16 are also provided. The topsheet application station 70 and the welding station 80 may be integrated with one another. As an alternative to the welding station 80, a gluing station can also be provided.

According to the invention, the device 1 has a transfer device 4, the bag body 10 are supplied either transversely or longitudinally. The transfer device 4 passes the supplied bag body 10 in transverse arrangement on the transport device 2 by means of a movement in the transport direction T. Invention s moves the transfer device 4 to be transported bag body 10 with respect to transported at transport speed V bag body by a feed distance Äy in the transport direction T and passes them then to the Transport device 2, wherein the transfer device 4, the bag body 10 moves in the transport direction T at least partially with a transfer speed U, which is greater than the transport speed V. So while the bag body 10 in the supply to the transfer device 4 have a distance yl from each other and with the transport speed T move in the transport direction, they have after the transfer to the transport device 2 a reduced distance y2 from each other, which comes about by the movement of the feed distance Äy. The feed distance Äy can thus be calculated as follows:

Feed distance Äy = bag body distance yl - bag body distance y2

By reducing the distance of adjacent bag bodies from yl to y2 between the tubular bag bodies during transport, the original length of the repeat xl is shortened by the feed distance ay to the repeat length x2. Thus, the throughput of bag bodies 10 can be increased by the device 1 at a constant transport speed T.

As shown in FIG. 2, the transfer device 4 may comprise retaining means 4b for gripping, holding and releasing the bag bodies. In this embodiment, the holding means 4b are designed as mechanical grippers, which are fastened to endless belts 4a revolving around pulleys 4c, 4d. One of the pulleys 4c is driven by a drive 7 which is (automatically) controlled by a controller 6 which can also drive the holding means 4b. As an alternative to grippers, the holding means 4b may also be designed as vacuum cups. By means of the controller 6, the feed distance Äy can be calculated and changed. Further, the controller 6 can control the speed of the drive 7 and controls the timings at which the holding means 4b grip and release the bag bodies 10.

Since, according to the invention, the spacings y1, y2 between the bag bodies 10 and the bottom cover sheets 19 are varied, the processing stations 30, 40, 50, 60, 70, 80 provided in the apparatus 1 are also single drives, for example controlled by the control 6 , Switches and actuators equipped to respond to the variable bag distances. For reasons of clarity, the connection of the controller 6 with the transfer device 4 and the processing stations 30, 40, 50, 60, 70, 80 is not shown in FIGS. 1 and 2. This connection is either point-to-point (serial or parallel), or a network connection. The controller 6 includes a computer, with which the feed distance Äy depending on the width (b) of the bag body 10 can be calculated so that there is a predefined distance y2 between successive bag bodies 10, 10 or between the cover sheets of successive bag body (distance y3, see Fig. 1). The controller 6 controls the transfer device 4 according to the calculated feed distance Äy.

For automatic operation of the device according to the Invention 1, a sensor 5 for detecting the width b of the bag body 10 is provided. The sensor 5 sends the detected width b to the controller 6. The sensor 5 may be camera-supported, for example, or detect the width b by means of light barriers.

In contrast to the prior art, in which the repeat is kept constant, the feed distance Äy is varied according to the invention as a function of the bag body width b and thus changes the length of the repeat. The smaller the bag body width b, the larger the feed distance Äy, around which the bag body is advanced. The distance y2 between the bag bodies 10 can thus be kept constant even with different bag body widths b.

For a gentle handling of the bag bodies and an exact picking up and transfer, the controller 6 controls the speed with which the transfer device 4 moves the bag bodies in the transporting direction T according to a speed profile. This speed profile includes the acceleration of the recorded bag body, which are supplied to the transfer device 4 at a speed lying between 0 and the transport speed V, on the transfer speed U and after a distance of the length of the feed stretch Äy dependent period of deceleration to the transport speed V. Farther On the basis of the detected bag width b and the predefined distance y2 of successive bag bodies, the controller 6 can calculate the desired position and desired length of the cover sheet 19 and optionally the desired position of a valve sheet 18 and control the cover sheet application station 70 based on this information she tailor a cover sheet 19 according to the desired length and applies it to the bag body 10 when it has reached the desired position. Similarly, the controller 6 controls the valve sheet insertion station 50 so that it applies a valve sheet 18 to the bag body 10 when it has reached the desired position. It should be noted that the length of the cover sheets mathematically results from the sack thickness determining measure by which the bottom side flaps 15, 16 are taken, since this measure the length of the fold edges, thus the length of the crossbeam and thus the length of the cover sheet 19th pretends. By fiction, contemporary transfer device 4 can be responded to width variations of the supplied bag body 10, and consequently increases the accuracy of the following processing stations and thus the quality of the bags are optimized.

Due to the smaller distance between the bag bodies 10, the efficiency of a hot-air welding device 80 for fixing the bottom cover sheets 19 is increased because the idling and the energy loss are minimized by unused emitted heat.

In many applications, the feed distance Äy is selected so that a predefined distance y2 between successive bag bodies is between 0 (i.e., the bag bodies are flush, see Fig. 3) and 5 cm (see Fig. 4). The shorter the distance of the bag bodies from each other, the shorter the time in which e.g. the hot air welding station 80 releases its thermal energy unused to the environment. Starting from this approach, in the embodiment according to the invention shown in FIG. 5, this distance is further reduced by overlappingly arranging adjacent bag bodies 10, 10 to the extent of the height h of the triangular envelopes. In mathematical terms, this results in a distance of -h between adjacent bag bodies. In order to bring the distance between the cover sheets 19 of adjacent bag bodies 10, 10 to 0, i. To arrange these flush, according to the invention in an extreme case (see Fig. 6), the overlap width of adjacent bag body 10, 10 can be selected as twice the height h of the triangular Eckeinschlags, resulting in a distance of -2h. For practical feasibility, however, it is necessary to fold at least one of the successive bag body a the other bag body facing longitudinal portion which has a width h.

It should be noted, however, that the extremely reduced distances between adjacent bag bodies 10, 10, as shown in Fig. 5 and Fig. 6, are not suitable for each subsequent processing station. For example, if the bag bodies 10 are pushed together by the transfer station 4 in Fig. 1 already at the transfer station that they overlap, folding the end portions 13 upwards at the folding station 30 and the opening of the end portions 13 at the bottom opening station 40 would not be possible. On the other hand, extremely close distances between the adjacent bag bodies also have the advantages described above. The present invention therefore also provides that the distances between adjacent bag bodies 10, 10 are reduced in several stages by arranging a plurality of transfer devices 4 according to the invention along the transport device 2. It can be after the example Floor opening station 40 may be arranged a second transfer station 4, with the distance y2 between adjacent bag bodies 10, 10 is reduced to -h. In Fig. 7, an embodiment of the inventive device for producing sacks of tubular bag bodies is shown schematically, which corresponds to that of Fig. 1, with the difference that in the embodiment of Fig. 7, the second transfer station 4 directly in front of the cover sheet application station 70 is arranged, whereby adjacent bag body 10, 10 can be pushed together even at the distance y2 = -2h. Alternatively, the distance may also be reduced stepwise with a second transfer station to the bottom opening station 40 and a third transfer station 4 directly in front of the cover sheet application station 70.

In one embodiment of the device according to the invention, the transport device 2 is divided into a first transport device and a second transport device, the bag body 10 move flat transverse to its longitudinal extent L in the transport direction T, wherein the first transport device is disposed upstream of the second transport device and the transport speed of first transport device is higher than the transport speed T of the second transport device. The transport speed of the first transport device thus corresponds to the transfer speed U.

Furthermore, it is also possible for only one transfer station, which is located directly after the bottom opening station 40 or farther behind along the transport device, to reduce the distances between the adjacent bag bodies. This means that the floor opening station 40 has "more time" to open the floors while optimally utilizing the thermal energy of the welding station 80.

The fact that the distances between the bag bodies or the bottom cover sheets are varied, the processing stations such as soil opener, valve inserters and cover sheet applicators must be equipped with individual drives in order to respond to the variable bag distances.

Claims

claims:

1. Device (1) for the production of sacks of tubular bag bodies (10), wherein the bag body preferably made of a fabric of plastic tapes or a nonwoven plastic material (eg plastic fleece) or a composite of the fabric of plastic tapes and the nonwoven plastic material or a are produced with a network structure associated plastic film, wherein the material optionally at least one side with at least one plastic layer and / or at least one plastic film, eg coated with an OPP film,

with at least one transport device (2) which transports the bag bodies lying transversely to their longitudinal extent (L) at a transport speed (V) in a transport direction (T), the bag bodies during their transport processing stations (30, 40, 50, 60, 70 , 80), with which at least one end region (13) of each bag body is formed into a cross bottom and optionally a cover sheet (19) is applied to the cross bottom,

characterized by at least one transfer device (4) which moves the bag body (10) to be transported by the transport device with respect to transporting speed (V) by a feed distance (Äy) in the transport direction (T) and transfers it to the transport device (2), wherein the transfer device (4), the bag body in the transport direction (T) at least partially moves at a transfer speed (U) which is greater than the transport speed (V), wherein the feed distance (Äy) is selected so that successive bag bodies overlap, wherein preferably corresponds to the overlap width of the single or double height (h) of the triangular Eckeinschlags (14), which results when turning the Bodenseitenklappen (15, 16), wherein in the latter case at least one of the successive bag body facing the other bag body longitudinal portion (10b) which has a width equal to the height (h) of the E corresponds to folding, is folded over.

2. Apparatus according to claim 1, characterized in that the transfer device (4) holding means (4b) for gripping, holding and releasing the bag body, wherein the holding means preferably comprise mechanical grippers and / or vacuum cups.

3. Device according to claim 2, characterized in that at least two holding means (4b) are provided, which are movable independently of each other.

4. Device according to one of the preceding claims, characterized in that the transfer device comprises a first transport device and a second transport device, the bag body (10) lying transversely to its longitudinal extension (L) in the transport direction (T) move, wherein the first transport device upstream is arranged by the second transport device and the transport speed of the first transport device is higher than the transport speed of the second transport device.

5. Device according to one of the preceding claims, characterized in that the processing stations comprise a bottom opening station (40), and the transfer device is arranged downstream of the bottom opening station (40).

6. Device according to one of the preceding claims, characterized by a controller (6) which calculates the feed distance (Äy) as a function of the width (b) of the bag body so that a predefined distance (y2, y3) between successive bag bodies or between the cover sheets (19) successive bag body (10), and the transfer device (4) according to the calculated feed distance (Äy) controls.

7. Apparatus according to claim 6, characterized by a sensor (5) for detecting the width (b) of the bag body, which transmits the detected width to the controller (6).

8. Device according to claims 6 and 7 in conjunction with claim 2, characterized in that the controller (6) controls the times at which the holding means (4b) engage and release the bag body.

9. Device according to one of claims 6 to 8, characterized in that the controller (6) controls the speed at which the transfer device (4) moves the bag body in the transport direction (T), according to a speed profile that accelerates to the transfer speed (U) and after a dependent on the length of the feed distance (Äy) time duration, the deceleration to the transport speed (V).

10. Device according to one of claims 7 to 9, characterized in that the control (6) on the basis of the detected bag width (b) and the predefined distance (y2) successive bag body, the cover sheet target position and desired length of the cover sheet (19 ) and optionally the desired valve leaf position of a valve sheet (18) is calculated and Based on this information, a cover-applying station (70) controls that it cuts a cover sheet (19) according to the desired length and applies it to the bag body when it has reached the cover-sheet set position, and optionally an operation station for the valve sheet. Inlay (50) controls that it applies a valve sheet (18) to the bag body when it has reached the desired valve sheet position.

11. A method for producing bags from tubular bag bodies (10), wherein the bag body preferably made of a fabric of plastic tapes or a nonwoven plastic material (eg plastic fleece) or a composite of the fabric of plastic tapes and the nonwoven plastic material or one with a network structure connected plastic film are produced, wherein the material optionally at least on one side with at least one plastic layer and / or at least one plastic film, eg coated with an OPP film,

wherein the bag bodies are transported lying flat transversely to their longitudinal extent (L) at a transport speed (V) in a transport direction (T), wherein at least one end region (13) is formed on the bag bodies during their transport to form a cross bottom and optionally a cover sheet (19) is applied to the cross bottom, characterized in that to be transported bag body (10) with respect to transported at transport speed (V) bag body by a feed distance (Äy) in the transport direction (T) and then moved at the transport speed (V), wherein the movement of the bag body on the feed path (Äy) takes place at least in sections with a transfer speed (U) which is greater than the transport speed (V), wherein the feed distance (Äy) is selected such that successive bag bodies overlap, preferably the overlap width the single or double height (h) of the three in the latter case, at least in one of the consecutive bag bodies, a longitudinal section (10b) facing the other bag body, which has a width which corresponds to the height (h), corresponds to the second bag body. corresponds to the corner impact, is folded over.

12. The method according to claim 11, characterized in that the feed distance (Äy) as a function of the width (b) of the bag body is calculated so that there is a predefined distance (y2, y3) between successive bag bodies (10) or between the cover sheets (19) successive bag body results, and the movement of the bag body according to the calculated feed stretch (Äy) is controlled.

13. The method according to claim 12, characterized in that the width (b) of the bag body with a sensor (5) is detected.

14. The method according to any one of claims 11 to 13, characterized in that the speed at which the bag body on the feed line (Äy) are moved, is controlled according to a speed profile, the acceleration to the transfer speed (U) and after one of the Length of the feed distance (Äy) dependent period of time includes the deceleration to the transport speed (V).

15. The method according to claim 13 or 14, characterized in that based on the detected bag width (b) and the predefined distance (y2) successive bag body, the cover sheet target position and the desired length of the cover sheets (19) and optionally the valve sheet Target position of valve leaves (18) are calculated and based on this information cover sheets (19) are cut according to the desired length and applied to the bag body (10) when they have reached the cover sheet target position, and optionally the valve blades ( 18) are applied to the bag body when they have reached the desired valve leaf position.

16. The method according to any one of claims 11 to 15, characterized in that to be transported bag body (10) after opening a bottom in the bag body to the feed distance (Äy) in the transport direction (T) moves and then with the transport speed (V) to move , wherein the movement of the bag body on the feed path (Äy) at least partially with the transfer speed (U), which is greater than the transport speed (V).