EP0527743A1

EP0527743A1 - Process and machine for tying up parcels or stacks with a ribbon of solderable plastics material

Info

Publication number: EP0527743A1
Application number: EP91905072A
Authority: EP
Inventors: Peter Lüdtke
Original assignee: Maschinenfabrik Gerd Mosca AG
Current assignee: Maschinenfabrik Gerd Mosca AG
Priority date: 1991-03-06
Filing date: 1991-03-06
Publication date: 1993-02-24
Also published as: WO1992015486A1

Abstract

Selon un procédé de ficelage de paquets ou de piles, on tire (4) d'un dévidoir un ruban (4) en matière plastique soudable, le début (5) du ruban est retenu à proximité du coin postérieur inférieur d'un paquet ou d'une pile (1) qui est poussé contre une partie tendue (8) du ruban, parallèlement au côté inférieur du paquet ou de la pile (1), puis on conduit le ruban (4) autour du paquet ou de la pile (1) jusqu'au coin où est retenu le début (5) du ruban et on y forme une boucle (17, 18) que l'on tire parallèlement à la zone initiale (21) du ruban d'enficelage, dont la partie (17) qui s'étend dans le sens d'avancement et qui recouvre la zone initiale (21) du ruban est soudée à la zone initiale (21). La partie de ruban ficelant le paquet ou la pile (1) est coupée du reste du ruban (4). La partie de ruban ficelant le paquet ou la pile est coupée du reste du ruban (4) à l'extrémité de la partie (18) de la boucle (17, 18) qui s'étend en sens opposé au sens d'avancement, immédiatement avant, pendant ou après le soudage, et les deux parties ou couches (17, 18) de la boucle sont pressées l'une contre l'autre, puis soudées l'une à à l'autre et à la zone initiale (21).According to a method of bundling bundles or stacks, a ribbon (4) of weldable plastic is pulled (4) from a reel, the beginning (5) of the ribbon is retained near the lower rear corner of a bundle or of a pile (1) which is pushed against a stretched part (8) of the ribbon, parallel to the lower side of the packet or of the pile (1), then the ribbon (4) is led around the packet or of the pile ( 1) to the corner where the beginning (5) of the ribbon is retained and a loop (17, 18) is formed there which is pulled parallel to the initial zone (21) of the insertion ribbon, the part of which ( 17) which extends in the direction of advance and which covers the initial zone (21) of the tape is welded to the initial zone (21). The part of ribbon stringing the package or stack (1) is cut from the rest of the ribbon (4). The part of ribbon stringing the packet or the stack is cut from the rest of the ribbon (4) at the end of the part (18) of the loop (17, 18) which extends in the opposite direction to the direction of advance, immediately before, during or after welding, and the two parts or layers (17, 18) of the loop are pressed against each other, then welded to each other and to the initial zone (21 ).

Description

Name: Method and machine for strapping

Parcels or stacks with a band made of weldable plastic

The invention relates to a method for strapping packages or stacks according to the preamble of claim 1 and to a strapping machine according to the preamble of claim 3.

Such a method and such a strapping machine are known from DE 39 18 674. In the known method, the upper part of the loop formed by the loop puller, which is adjacent to the starting area of the strapping, becomes the. Beginning area of the strapping by means of a heating tongue and pressure jaws welded and the strapping thus closed is separated from the rest of the belt on the side of the welding device pointing in the feed direction after the gripper has previously grasped the new beginning of the belt. With this method, it is necessary that the gripper, which detects the beginning of the strip, moves from the side of the welding device in the feed direction to the other side of the welding device and has to be rotated through 360 ° in each working cycle.

The invention has for its object to provide a method for strapping packages or stacks, in particular newspaper stacks, in which the transfer of a gripper from a position in front of the welding device into a position behind the welding device is not necessary.

This object is achieved by the features of patent claim 1.

The invention is also based on the object of creating a machine for strapping packages or stacks, which can tie up packets or stacks advanced on a conveyor line in rapid succession with little mechanical effort and with high operational reliability.

This object is achieved by the features of patent claim 3.

The use of an ultrasonic welding head has the advantage of immediate operational readiness compared to a heating tongue because preheating is not necessary. An ultrasonic welding head quickly and reliably welds the two layers of the loop between the initial area of the tying against the counterplate and the loop folded on the ultrasonic welding head to the initial area of the tying. The double overlap of the starting area of the tying by the folded loop ensures that the two parts or layers of the loop nestle against the underside of the package or stack and that there is no end protruding from the package or stack that can lead to injuries.

In the following description, embodiments of the machine according to the invention are explained in more detail with reference to the drawings. The drawings show in

1 to 6 show six different operating states of the strapping machine according to the invention in a schematic representation, FIG. 7 shows a schematic representation of the machine after pulling the loop and shortly before welding.

In Fig. 1, the band 4 is made of weldable plastic, which is guided by a band feed, which is formed here by the supply roll 3, to a gripper consisting of lower part 6 and upper part 7, a chord 8 for a package 1 which is on a between the supply roll 3 and the gripper 6, 7 arranged conveyor section 2 against the tensioned chord 8 is advanced. The packs 1 can be fed by means of conveyor belts or pushers located on both sides of the strapping plane. The beginning of the band 5 is first held by the gripper 6, 7.

In Fig. 2, the package 1 has moved the tendon 8 as far as to the right that the band 4 surrounds the package 1 on its underside, front and top. Between the underside of the pact 1 and the. Beginning area 21 of the band 4, the upper part 10 of a clamp 9, 10 and a counter plate 13 are inserted, which form part here. After the band 4 is clamped and held between the lower part 9 and the upper part 10 of the clamp, the gripper 6, 7 releases the beginning of the band 5. The upper part 7 of the gripper is withdrawn from the tying level. A smooth stripper 14 which can be pushed in and retracted into the Umschnü¬ tion plane smoothes the beginning of the tape 5 released by the gripper 6, 7 by pressing it against the counter plate 13 and ensuring that the beginning of the tape 5 and the. Plant. The starting area 21 and the counter plate 13 extend from the beginning of the band 5 to the clamp 9, 10. As soon as the back of the package 1 has reached the counterplate 13, the belt feeder 15 arranged above the chord 8 presses the belt 4 downward, with a distance below the conveyor path 2, so that the belt 1 envelops the package 1 on all sides. This state is shown in Fig. 3. Above the band feeder 15, which is lowered downwards, and below the level of the. Start area 21, a loop puller 16 can be inserted into the constriction plane, which is movable in the direction of advance parallel to the counterplate 13 and below the. Start area 21, a loop which is drawn from an upper one , the start region 21 adjacent part 17 and a lower part 18 leading back to the band feeder 15.

As shown in FIG. 4, the open gripper 6, 7 is brought into the constriction plane in this operating state. The 1 upper part 7 of the gripper is located between the upper part 17 of the loop and the lower part 18 of the loop, so that when closing the gripper 6,7 the lower part 18 of the loop in the vicinity of the lowered belt feeder

5 15, that is, in the end region of the loops 17, 18 is detected.

In FIG. 5, an ultrasonic welding head 12 located below the counter plate 13 and below the loop 17, 18 moves up and welds both parts or layers 17, 18 of the

10 loop against the. 21 initial range. The knife 20 and the lower part 6 of the gripper 6, 7 run ahead, so that the band 4 and a band beginning 5 'of the following working cycle are clamped in before the welding head 12 carries out the welding. The ultrasonic welding head 12

15 presses the two parts 17, 18 of the loop against the initial region 21 of the strapping lying on the counterplate 13 and welds the two layers of the folded loop 17, 18 against the initial region 21.

20 As shown in FIG. 6, the loop puller 16, the band feeder 15, the clamp 9, 10, the counter plate 13 with the upper part 22 of the clamp 7.22 as well as the ultrasonic welding head 12 and the knife 20 return to their respective positions ¬ starting positions. The tied package 1 is free and

25. The tendon 8 is ready for the tying of the next package. The gripper 6, 7 holds the new band beginning 5 'until, according to FIG. 2, the clamp 9, 10 takes over the holding.

0 In the operating state shown in FIG

Downward movement of the belt feeder 15 triggered by a sensor or by a light barrier. The sensor or the light barrier reports to the drive of the belt feeder 15 when a package or a stack has passed the movement level of the belt feeder 15. After the clamp 9, 10 has taken over the holding of the. Start area 21 and the gripper 6, 7 has released the band start 5, the upper part 7 of the gripper he withdrawn 6.7 from the tying level. In the operating state shown in FIG. 5, this upper part 7 of the gripper is brought into the constriction plane in order to grasp together with the lower part 6 the part 18 of the loop 17, 18 running from the loop puller 16 to the band feeder 15 in the vicinity of the band feeder 15. The parts 6, 7 of the gripper can be displaced vertically independently of one another, so that they can be shifted from a lower position to the higher position shown in FIG. 5.

In the operating state shown in FIG. 5, the upper part 7 of the gripper 6, 7 and the end region 22 of the counterplate 13 pointing counter to the feed direction form a further clamp 7, 22, which clamps the band 4 stretched around the package or stack 1 holds in the area of the beginning of the upper part 17 of the loop 17, 18 before the loop puller 16 is withdrawn from the strapping plane. This upper part 7 of the gripper 6, 7 and lower part 7 of the second clamp 7.22 also forms a separating device with the knife 20. The lower edge of the upper part 7 of the gripper 6, 7, which is in the feed direction, is designed as a shear bar which, together with the knife 20, welds the lower part 18 of the loop 17, 18 from the new beginning of the band 5 'gripped by the gripper 6, 7. separates. The knife 20 can be vertically movable independently of other parts of the machine, but it can also be fixed rigidly to the lower part 6 of the gripper 6, 7 in such a way that the band is cut shortly before the gripper 6, 7 clamps the new beginning of the band 5 ' .

7, the operating state according to FIG. 4 is shown enlarged. Here the tape 4 drawn off from a supply roll is guided over a roll serving as a tape feed 11. The chord 8 forms between this tape feed 11 and the gripper 6, 7. Before the ultrasonic welding head 12 is brought up to weld the two parts 17, 18 to the. Beginning area 21, the second clamp 7, 22 clamps the starting area of the upper part 17 of the. Loop 17.18 tight to maintain the tension of the tying when pulling the loop puller 16 out of the tying plane just prior to welding.

So that the packs or stacks 1 can be strapped without stopping, the strapping machine can be moved in the forward stroke direction of the packs or stacks 1 at the conveying speed of these packs or stacks 1 and can be moved back at a greater speed against the feed direction. The greater this return speed, the smaller the distances between the packages 1 on the conveyor line 2.

In order to also be able to carry out a strapping transversely to the feed direction of the conveyor section 2, the conveyor section 2 has a transversely running gap of, for example, 8 cm, so that a strapping plane can be set up in this gap with a gripper, 6, 7. a first clamp 9, 10, a counter plate 13, a second clamp 7, 22 and an ultrasonic welding head 12 with a knife 20

The tendon 8 located next to the conveyor path 2 is turned out by means of a protuberance which can be moved transversely to the conveyor path 2 and whose end face is somewhat higher than the packages or stacks to be strapped. Before a package or stack reaches the gap, the protuberant moves from one side of the conveyor section 2 to the other side, so that the package or the stack can move into the inverted chord 8. The package or the stack 1 then stops above the transverse gap, and the belt feeder 15 moves into its lower position, so that the loop puller pulls a loop 17, 18 under the counter plate 13 and the ultrasonic welding head 12 pulls the folded loop 17 , 18 welds against the. Start area 21 of the strapping. The protuberance detects the tendon 8 by means of a relatively thin sheet which turns the tendon 8 in transverse direction to the conveyor path 2 and that without difficulty in the further transport of the packages 1 from the gap between the side wall of the package 1 and the Umschnürimg slides out. This machine for cross-wise tying has the advantage that it is composed largely of the same parts and units.

SPARE BLADEΓ Reference symbol list:

1 package or stack

2 conveyor line

3 supply roll 4 tape

5 Beginning of the band

6 lower part of the gripper

7 upper part of the gripper 8 tendon

9 lower part of the clamp

10 Upper part of the clamp

11 tape feed

12 welding head 13 counter plate

14 smooth scrapers

15 belt feeders

16 loop pullers

17 upper part of a loop 18 lower part of the loop

20 knives

21. Starting area of the tying

22 Upper part of the second clamp 7.22

Retractable from the tying level:

9; 10? 13? 14? 16

Movable up and down: 6; 7? 15? 12? 20th

REPLACEMENT LEAF

Claims

PATENT CLAIMS:

1. Method for tying up parcels or stacks, with a tape (4) made of weldable plastic that can be pulled off a supply roll, in which the tape beginning (5) near the rear lower corner of a against a tensioned chord (8) of the tape ( 4) advanced package or stack (1) is held parallel to its underside and the band (4) is guided around the package or stack (1) to the corner with the beginning of the band (5) and there is a loop (17, 18) is drawn parallel to the starting area (21) of the tying band (4), the part (17) extending in the direction of advance and overlapping the starting area (21) is welded to the starting area (21) and the closed tying of the package or stack ( 1) is separated from the rest of the band (4), characterized in that shortly before, during or after the welding, the strapping at the end of the part (18) of the loop (17, 18) which runs counter to the feed direction from the rest of the band (4 ) is separated and both parts or layers (17, 18) of the loop are pressed against one another and welded to one another and to the starting area (21).

2. The method according to claim 1, characterized in that the welding of the two parts or layers (17, 18) of the folded loop with the initial region (21) of the tying is carried out by ultrasound.

3. Machine for strapping packages or stacks (1), with a removable from a supply roll (3) tape (4) made of weldable plastic, in which the packages or stacks (1) by feeding on a conveyor line (2) one before to tie up bundles or stacks (1), the stretched chord (8) of the band (4) turns out between a gripper (6, 7) holding the beginning of the band (5) and one at a distance A belt feeder (15) is arranged above the conveyor line (2), a belt feeder (15) being arranged above the tensioned chord (8), the starting position of which is located at a distance above the tops of the packs or stacks (1) and after Passage of a package or stack (1) can be lowered to a height below the conveyor section (2) and in doing so moves the flipped tendon (8) towards the beginning of the band (15) and a loop puller in the lowered position of the band feeder (15) (16) can be pushed into the constriction plane and can be moved in the feed direction, which pulls a loop having an upper part (17) and a lower part (18) under the starting area (21) and a welding device is provided which covers the starting area ( 21) of the strapping is welded to the upper part (17) of the loop (17, 18) and a separating device (20) is provided which separates the strapping from the rest of the band (4), the gripper (6 , 7) the newly formed strip beginning (5 ') for the following working cycle is detected, characterized in that an ultrasound welding head (12) which can be moved upward and which is arranged under the loop (17, 18) Parts (17, 18) of the loop are welded to the start region (21) of the strapping and the separating device (20) is arranged in such a way that it cuts through the band (4) at the end of the lower part (18) of the loop.

4. Machine according to claim 3, characterized in that above the ultrasonic welding head (12) between the initial region (21) of the strapping and the underside of the package or stack (1) a counter plate (13) can be inserted, the end region pointing in the feed direction the upper part (10) forms a first clamp (9, 10) and its end region, which points against the direction of advance, forms the upper part (22) of a second clamp (7, 22).

5. Machine according to .Anspruch 3 or 4, characterized in that the gripper (6,7) with its lower part (6) and upper part 1 (7) and the knife (20) are controlled in their upward movement so that after the formation of the loop (17, 18) they lead the upward movement of the ultrasonic welding head (12) and first the tying band between the

5 upper part (7) and the upper part (22) of the second clamp (7, 22) is clamped, then the knife (20) which slightly leads the lower part (6) of the gripper (6, 7) and cuts the band (4) and the gripper (6, 7) detects the new beginning of the band (5 ') and then the ultrasonic welding head (12) presses the 0 loop (17, 18) together and against the. Beginning area (21) and welds the three band sections together.

6. Machine according to one of claims 3 to 5, characterized ge indicates that the knife (20) on the lower part (6) of the 5 gripper (6, 7) is attached and the lower edge of the upper part (7) of the upper part (7) lying in the feed direction Gripper is designed as a shear bar.

7. Machine according to one of claims 3 or 6, characterized in that it can be moved in the feed direction at the feed speed of the packages or stacks (1) and after completion of a constriction with the spacing of the packages or stacks (1) on the conveyor line ( 2) adjusted speed is reversible. * 5

8. Machine according to one of claims 3 to 8, characterized ge indicates that a the conveyor section (2) transversely running gap one of the first machine corresponding strapping machine for a transverse strapping is arranged 0, in which the tensioned tendon (8) next to the conveying path (2) is located and the tendon (8) can be protruded by a protuberance that can be pushed forward transversely to the conveying path (2), so that a package or a stack (1) can enter the protruding tendon (8) and in which the protuberance can be pulled out of the constriction parallel to the conveyor section (2) and moved back into its starting position in front of the tendon (8) and between this starting position of the protuberance and one side of the conveyor line (2), on which the gripper (6, 7), the second clamp (7, 22) and the counterplate (13) are also arranged, a belt feed (11), a belt feeder (15) and a loop puller (16) are arranged.

9. Machine according to one of the .Claims 3 to 8, characterized in that a insertable into the constriction plane and the initial region (21) of the constriction against the counter plate (13) pressing smooth stripper (14) is provided, which after smoothing the beginning of the band (5) which is bent off by the gripper (6, 7) can be pushed back out of the tying level.

REPLACEMENT LEAF