EP0126878B1 - Web feeding and guiding device for a packaging machine - Google Patents

Abstract

A feeding means for feeding a material web in a packaging machine comprises feeding chains, sprocket wheels and an engagement element for feeding the feeding chains. In order to facilitate the insertion and clamping of the material web the engagement member is designed such that in a first portion of the travelling section the movable clamping member is lifted from the fixed clamping member in a substantially vertical direction and in a second portion of the travelling section following the first portion the movable clamping member is additionally moved laterally away from the edge of the material web to be gripped.

Description

The invention relates to a transport device according to the preamble of claim 1.

Such a transport device is known from DE-OS 30 22 065. This is designed so that when the movable clamp part is lifted, it simultaneously lifts and is tilted outwards from the location of the material web. The transport device is designed so that in the closed state, in which the film is gripped, the bracket is prevented from tipping backwards. In the known device, the overrun element has a plurality of centering recesses which are arranged on a circle extending parallel to the chain wheel, so that the distance from the circle to the plane of the chain wheel is always the same.

Such a transport device is also known from DE-OS 22 24 854. In this case, the fixed clamp parts are firmly connected to bushings in which a bolt which is fixedly connected to the movable clamp parts is slidably guided in such a way that inclination of the bolt and thus the movable clamp part is avoided.

From AT-PS 31 64 28 a transport chain with lateral angle plates attached to the chain links is known, the lateral angle plates having horizontal bolts which engage in elongated holes on the movable bracket part. The interacting with such a transport chain, designed as thrust washers have pocket-like recesses which cooperate with the chain links so that the movable bracket parts are raised and lowered obliquely. As a result, the clamping jaw of the movable clamp part is not lowered vertically onto the clamping jaw of the fixed clamp part and can thereby cause the material web to shift when it is closed. Furthermore, both the structure of the chain links and the thrust washer are complicated.

DE-OS 23 55 921 and EP-OS 0 039 056 transport devices of the type described above are known, in which the casserole element has such an inclined surface that the clip parts running on it are not only raised but also tilted to the side, so that the distance between the clamp parts of the guide chains running on both sides of the lower track increases and becomes larger than the lower track.

The object of the invention is to provide a transport device of the type described in the opening paragraph, in which simultaneous unimpeded insertion and secure gripping of the material web is made possible even if the width of the material web fluctuates due to the production process. In particular, the movable clamp part should have as far as possible no component of movement against the center of the material web when gripping the material web, so that pushing of the material web against this center is avoided.

This object is achieved by a transport device according to claim 1. In addition, since the movable clamp part in the section of the actual lifting and the section of the actual lowering moves perpendicularly with respect to the fixed clamp part, it is achieved that the chain is stressed considerably less than a chain in which lifting and tipping take place at the same time.

The developments of the invention are described in the subclaims.

• Figur 1 eine Seitenansicht einer Verpackungsmaschine mit Transporteinrichtung in schematischer Darstellung ;
• Figur 2 einen Schnitt durch einen Teil einer ersten Ausführungsform der erfindungsgemäßen Verpackungsmaschine entlang der Linie 11-11 in Fig. 1 ;
• Figur 3 eine Teildarstellung einer zweiten Ausführungsform entsprechend der linken Hälfte der in Fig. 2 gezeigten Darstellung entlang der Linie 111-111 in Fig. 4 ;
• Figur 4 eine Seitenansicht von Transportkette mit Auflaufscheibe in Richtung der Pfeile IV-IV in Fig. 3, um 90° gedreht ;
• Figur 5 einen Schnitt entlang der Linie V-V in Fig. 4 ;
• Figur 6 einen Schnitt durch eine geschlossene Halteklammer gemäß der zweiten Ausführungsform entlang der Linie VI-VI in Fig. 4 ;
• Figur 7 eine Teildarstellung einer dritten Ausführungsform entsprechend der in Fig. 3 gezeigten Darstellung entlang der Linie VII-VII in Fig. 8 ;
• Figur 8 eine Seitenansicht der Transporteinrichtung nach der dritten Ausführungsform in Richtung der Pfeile VIII-VIII in Fig. 7 ; und
• Figur 9 eine abgewickelte Darstellung des Verlaufs der Führungsnut bei der dritten Ausführungsform.

Exemplary embodiments of the invention are described below with reference to the figures. From the figures show:

• Figure 1 is a side view of a packaging machine with transport device in a schematic representation;
• Figure 2 shows a section through part of a first embodiment of the packaging machine according to the invention along the line 11-11 in Fig. 1;
• FIG. 3 shows a partial representation of a second embodiment corresponding to the left half of the representation shown in FIG. 2 along the line 111-111 in FIG. 4;
• FIG. 4 shows a side view of a transport chain with a thrust washer in the direction of the arrows IV-IV in FIG. 3, rotated through 90 °;
• 5 shows a section along the line VV in Fig. 4;
• 6 shows a section through a closed retaining clip according to the second embodiment along the line VI-VI in Fig. 4;
• FIG. 7 shows a partial representation of a third embodiment corresponding to the representation shown in FIG. 3 along the line VII-VII in FIG. 8;
• Figure 8 is a side view of the transport device according to the third embodiment in the direction of arrows VIII-VIII in Fig. 7; and
• Figure 9 is a developed representation of the course of the guide groove in the third embodiment.

The invention is used in particular in a deep-drawing packaging machine which is generally designated by the reference number 1 in FIG. This has a machine frame 2, on the input side of which a roller 3 with foil material is arranged, from which the material web 4 is drawn off from this foil material and is guided via a deflection roller 5 to a transport device 6.

The transport device 6 has in a known manner on both sides of the material web endless chain runs 7, which are guided and driven at their deflection points via chain wheels. Holding clips are fastened to the chain links in a known manner, with which the material web 4 is gripped laterally and through the processing stations of the deep-drawing packaging machine is guided. On the exit side, the material web is released again by the holding clips.

As can best be seen from FIG. 2, the transport chains 8, 9 run on chain wheels 10, 11, which are mounted in the machine frame 2 in a known manner by means of roller bearings and axles. The right and left chain center with the associated drive devices are mirror-symmetrical. Therefore only one page is described.

A description is first given with reference to FIGS. In the embodiment shown there, each chain link has a retaining clip 12. This has a fixed clamp part 13 in the form of an angle plate riveted onto the bolt 14 of the chain link. Furthermore, a movable clamp part 15 is provided, which is designed in the form of a box-shaped clamp with a movable clamping jaw 151, side walls 154, 155 and abutments 156, 157 bent over at the bottom. The fixed clamp part 13 has a fixed jaw 131 with a bore 132. On the underside of the fixed jaw 131, axially aligned with this bore, a collar bushing 133 is provided, which is firmly connected to the fixed jaw. A compression spring 23 is provided between the collar 139 of the collar bushing and the lower legs of the movable clamp part forming the abutments 156, 157, which biases the movable clamping jaw 151 into the closed position.

At its end facing away from the chain, the movable jaw 151 has a cutting edge 153 which, in the closed position, engages in a notch 138 provided on the fixed jaw 131.

On the underside of the upper part of the movable clamping jaw facing the fixed clamping jaw there is provided a fixing bolt 152 which is firmly riveted to the movable clamping jaw and which is arranged so that it is aligned coaxially with the collar bush 133 in the closed state of the holding clamp, and the outside diameter of which is selected that it can slide in the flange bushing. Its length is chosen so that it is first a path in the flange bushing and then emerges from this.

The fixed clamp part 13 has two side parts 134, 135 in the form of tabs bent forward substantially at a right angle, into which guide pins 136, 137 are introduced. The movable clamp part 15 has elongated holes 158 on each of its side walls 154, 155. The elongated holes 158 extend parallel to the direction of the bolt 152. The bolt-shaped guide pins 136, 137 are received by the adjacent elongated holes 158.

FIG. 6 shows a section through a closed holding clip according to the embodiment shown in FIGS. 3-5. In this closed state, the movable jaw 151 is pressed by the compression spring 23 with its cutting edge 153 toward the fixed jaw 131. As a result, the bolt 152 is moved into the flange bushing 133 by a certain amount. It can be seen from FIG. 6 that when the movable clamp part 15 is raised or lowered, it is moved in a direction perpendicular to the fixed jaw 131 as long as the bolt 152 is guided in the collar bush 133.

In addition to the chain wheel, a thrust washer 30 is provided, which lies in the area between the retaining clips deflected around the chain wheel axis and serves to open the clamping jaws for the purpose of threading and engaging or releasing the material web 4 to be guided. The thrust washer 30 is arranged concentrically with the sprocket axis 31. Its axis 32 forms an angle a with the chain wheel axis 31. The thrust washer 30 is rotatably supported by a ball bearing 33. The sprocket 10 and the thrust washer 30 are both mounted on a common sprocket shaft 34. In order to incline the thrust washer 30, a hub 36 with a bearing pin 37, which is keyed to the chain wheel shaft 34 by means of a wedge 35, is provided coaxially to the chain wheel axis 31. The axis of the bearing pin coincides with the axis 32 of the thrust washer and forms an angle α with the hub axis, which coincides with the chain wheel axis 31. The axis of the bearing journal is pivoted through the angle a at a point 38, which is determined by the intersection of a line of intersection 39, which is perpendicular to the center of the run-up surface, with the sprocket axis 31 or the sprocket shaft 34 can be fixed about the sprocket axis 31.

The thrust washer 30 has a run-up surface 40 which, as can best be seen from FIG. 3, has a flat section 41 on its side facing the material web 4 to be gripped, which extends from the outer edge of the thrust washer facing the material web to the cutting line 39 extends. This is followed by a convex section 42, which is delimited by a projecting guide edge 43.

The holding clamp 12 is opened by running it onto the thrust washer 30 in point 44 (FIG. 4). The movable clamp part 15 is lifted vertically by the guide of the bolt 152 in the collar bush 133 and the guide pins 136, 137 in the elongated holes 158, until the bolt 152 emerges from the collar bushing 133 at about point 45. Due to the inclined thrust washer 30, the concave section, as shown in FIG. 5, engages with the abutment 156, 157 at this point. A tilting process now begins, that is to say after the movable clamp part has been raised, due to the increasing distance between the ramp surface 40 and the chain wheel 10 due to the inclined position of the thrust washer 30, in which the movable clamp part moves over the position shown in FIG showed rolling position on the convex portion and guided by the guide edge 43 is tilted into the position shown in Figure 3. The width of the convex section 42 is thus selected so that from point 45 the movable clamp part 15 is continuously forced outwards by the convex section moving away from the chain edge 10 and the guide edge 43 into the inclined position shown in FIG. At point 46 the retaining clip is fully open and remains in the open position until point 47. The maximum extension is reached in point 48.

As can best be seen from FIG. 2, a guide drum 49 is freely rotatable between the opposite chain edges 10, 11 for deflecting the material web 4 drawn off from the supply roll 3. The position of the thrust washer 30 is set so that the run-up surface 40 reaches its maximum distance from the adjacent sprocket 10 at the angular position corresponding to point 48, which is on the same radius passing through the axis of rotation of the thrust washer and guide drum, on which point 50 lies on which the material web 4 strikes the guide drum 49. In the exemplary embodiment shown in FIG. 1, this point 50 lies on a horizontal line passing through the mentioned center point. It is thereby achieved that at the entry point of the material web, the movable jaw 151, which interacts with the fixed jaw 131 designed as a horizontal leg, is deflected to such an extent that the material web 4 can be threaded and guided onto the fixed jaw 131, without the material web 4 being movable Jaw 151 would come into contact. After turning further beyond point 48, the movable clamp part 15 first folds back to the vertical position up to point 53. At point 53, the bolt 152 plunges into the collar bush 133, whereupon there is a vertical backward movement of the movable clamp part into the closed starting position, the movable clamping jaw 151 firmly gripping the material web 4 by interaction with the fixed clamping jaw 131. The closed end position is reached in point 54. On the outlet side 54 ', the two thrust washers are designed accordingly, so that the opening and closing process takes place there in a corresponding manner and the material web is released.

In the first embodiment shown in FIG. 2, the features which correspond to the previously described embodiment are identified by the same reference symbols. The two sides are again mirror images of each other so that only one side is described.

The fixed clamp part 13 'is designed as an angle piece, the vertical web of which is connected to the chain link by means of the bolt 14 and which has a horizontal fixed jaw 131. The fixed jaw has a bore 56. The movable clamp part 15 'has a fixing bolt 152' which, on its end facing away from the thrust washer 30 ', has a movable clamping jaw 151' designed as a riveted mushroom-shaped or spherical cap-shaped head 55 which, in the closed state, interacts with a material web and interacts with the fixed clamping jaw 131 holds on. On the side facing away from the head, the bolt 152 ′ has a ring 57 near its other end. In contrast to the first exemplary embodiment, the collar bush 133 is not firmly connected to the fixed clamping jaw 131. Between the collar bushing 133 and the ring 57, the compression spring 23 is provided, which abuts the collar bushing 133 at one end and the ring 57 at its other end and which prestresses the movable clamp part 13 'into the closed position.

The thrust washer 30 'is mounted in the same way as in the embodiment described first. However, the run-up surface 40 'differs from the embodiment described above. The thrust washer has centering bores 58, which are designed as countersunk bores in the example shown. The centering bores 58 are circumferentially offset from one another on a circumferential line. Their angular spacing corresponds to the angular spacing of the retaining clips 12 guided around the chain wheel. The thrust washer 30 'has on the side facing the chain wheel 10 a plurality of recesses 61 which are offset with respect to one another in the circumferential direction. The sprocket 10 has on its side 59 facing the thrust washer 30 'a corresponding number of projecting areas 60, the shape of which is designed such that they can engage with an adjacent recess 61. The protruding areas 60 are arranged so that they engage in the area in which the pulley and sprocket are closer together.

The centering holes 58 are circumferentially distributed such that a centering hole 58 is assigned to a jaw in the direction parallel to the axis 31. The centering bores take over the guidance of the associated bolts by engaging in the associated bores and being guided and held therein. The lateral deflection takes place through the side wall of the centering hole, which corresponds to the guide edge 43 of the embodiment described first.

A third embodiment of the invention is shown in FIGS. 7 and 8. Components that correspond to the previous embodiments are identified by the same reference numerals. The embodiment according to FIGS. 7 and 8 differs from the second embodiment according to FIGS. 3-5 in particular in that, instead of the thrust washer 30, a plurality of sliders 62 moved with the sprocket 10 are provided, each of which functions in a part of the section Corresponds to ramp area 30. The sliders 62 are arranged on the inner end face of the sprocket 10 at the same distance from the sprocket axis in such a position and at such a distance from one another that the outer surface of the slider 62 forming the run-up surface 40 with the movable clamp parts 15 of the holding clamps 12 fed with the chain comes into engagement. The distance of the run-up surface 40 from the sprocket axis is equal to the distance of the run-up surface 40 of the thrust washer 30 from its axis 32. In the same way as the run-up surface of the thrust washer 30, the run-up surface of the slider 62 has a flat section 41 and a convex section 42 which is delimited by a projecting guide edge 43. In addition, the run-up surface 40 of the slide 62 is delimited on the side facing away from the chain wheel 10 by a second guide edge 73.

To mount the slide 62, fitting bores 63 are provided on the inner end face of the sprocket 10 in a circle around the sprocket axis 31, into which guide pins 64 arranged parallel to the sprocket axis 31 are inserted. On each of the guide pins 64, a slide is slidably mounted in the direction of the guide pin 64 and thus the chain wheel axis 31 via slide bearing bushes 66, 67 inserted in a bore 65. On the side facing the slider 62, the sprocket 10 has a cylindrical collar 68 with a plurality of recesses 72, which are used for guiding the sliders against rotation in the direction of the guide pins 64. A guide pin 64 is arranged in each of the cutouts 72. Through this storage, the individual slider 62 are rotated with the sprocket 10. However, their distance from the end face thereof can be changed by moving the slide in the recesses 72 on the guide pins 64.

To control the distance of the sliders 62 from the chain wheel 10, a cam guide system is used, which has a cam 69, which is attached to the chain wheel axis 31 on the side of the slider 62 and engages in a groove 71 arranged on the circumferential surface of a cam disk 70. The cam plate 70 is mounted on the sprocket shaft 34 in a rotationally fixed manner via the feather key 35.

The groove 71 extends in a ring around the circumferential surface of the cam disk 70 and is therefore always at the same distance from the chain wheel axis 31 in the radial direction. In the axial direction of the cam disk 70, it has the shape of a curve, i. H. a changing distance to the chain wheel 10 around the cam disk 70. As shown in FIG. 9, the groove 71 has a small first distance from the chain wheel 10 in a first section and the distance increases to a second distance in a subsequent second section. In a third section, the groove essentially maintains this second distance and then falls back to the first distance. The first section extends at an angle from approximately point 53 to point 45 in FIG. 8, the second section from point 45 to point 46, the third section from point 46 to point 47 and the fourth section from point 47 to point 53 .

In operation, a holding clip 12 runs onto a slide 62 at point 44. During the further movement from point 44 to point 45, the cam 69 is guided in the first area of the groove. As a result, the movable clamping jaw 151 is lifted vertically from the fixed clamping jaw 131 until the bolt 152 emerges from the collar bushing 133. Due to the increasing distance of the groove 71 from the sprocket 10 at point 45, the slide 62 is moved away from the sprocket 10 via the cams 69 and thereby tilts the movable clamp part 15 around the guide pins 136, 137 so that the movable clamping jaw 151 moves away from the material web. or is pivoted towards the chain. The movable clamp part 15 rolls onto the convex section 42 of the run-up surface 40 in the same way as with the run-up wheel 30. The clamp 12 is held in this position until the point 47 is reached. By decreasing the distance of the groove 71 from the sprocket 10 in the angular range between the point 47 and the point 53, the slider 62 is moved back to the sprocket 10 and the movable clamp part 15 is tilted back into the vertical position. In the following first section of the groove 71 between points 53 and 54, the slide is held by the groove 71 near the sprocket 10, and the movable jaw 151 is returned perpendicular to the fixed jaw 131.

A predetermined curve shape of the groove 71 was described above as an example. However, it is the advantage of the third embodiment that the curve shape of the groove 71 is freely selectable and thus the pivoting or tilting of the movable clamp part 15 depending on the angular position of the retaining clip 12 is freely controllable by a corresponding design of the groove 71.

The obliquely arranged thrust washer 30 or the shape of the annular groove 71 ensures that the movable jaw 151 is first lifted vertically from the fixed jaw 131, then pivoted outwards or towards the sprocket or away from the material web, then into one position swung back vertically over the fixed jaw and lowered vertically onto it. As a result, the material web can be easily gripped by the holding clip 12 without being pushed from the lateral holding clips to the center of the packaging machine.

Two embodiments of the clip opening device have been described in connection with the description of the second and third exemplary embodiments. As shown in the first embodiment with reference to the thrust washer, both the thrust washer and that in connection with FIGS. 7-9 can be written slide device can be used in connection with each bracket, which allows lifting and pivoting of the movable bracket part.

Claims (15)

1. A conveyance device for feeding a web (4) from an entrance side to an exit side in a packaging machine (1), comprising conveyor chains (8, 9) and sprocket wheels (10, 11) for guiding the conveyor chains (8, 9), each conveyor chain having chain links and clamp carriers (12) connected therewith for gripping an edge of the web (4), a fixed clamping member (13) connected with the associated chain link (13), and a movable clamping member (15), and a compression spring (23) for biasing the movable clamping member (15) into the closed position, and a take-up element (30, 62) being engageable with the movable clamping element (15) along a runway portion of the chain, characterized in that the take-up element (30, 62) is formed such that the movable clamping member (15) is lifted substantially vertically from the fixed clamping member (13) in the first section of the runway portion and is moved additionally relatively to the fixed clamping member (13) sideways away from the web edge to be gripped.

2. The conveyance device in accordance with claim 1, characterized in that the engaging place of the movable clamping element (15) with the take-up element (30, 62) is guided along a curve having a distance from the plane of the sprocket wheel (10, 11) varying along the runway portion.

3. The conveyance device in accordance with claim 1 or 2, characterized in that the take-up element (30, 62) is formed as take-up reel (30) being formed with a take-up surface (40) as engaging place and that the shaft (32) of the take-up reel (30) is arranged such that it forms an angle with the sprocket wheel shaft (31).

4. The conveyance device in accordance with claim 3, characterized in that the shafts (32) of the take-up reels (30) being situated at the entrance side are inclined relatively to the shafts (31) of the corresponding sprocket wheels (10,11) such that the distance of the take-up surfaces (40) is larger at the entrance side (48) than at the position of the take-up reels being shifted by 180°.

5. The conveyance device in accordance with claim 4, characterized in that the take-up surfaces (40) comprise their maximal distance at the entrance position (50) of the web (4).

6. The conveyance device in accordance with claim 4 or 5, characterized in that the take-up reels being arranged on the exit side are inclined in a corresponding way to the exit position (54').

7. The conveyance device in accordance with claim 1 or 2, characterized in that the take-up element is formed as a slider (62) being supported slidably in the axial direction of the sprocket wheel, the slider engaging in a keyway (71) extending along the runway portion, the distance of the keyway to the plane of the sprocket wheel varying along the runway portion.

8. The conveyance device in accordance with claim 7, characterized in that the sprocket wheel (10) comprises a cylindrical flange (68) having recesses (72) for guiding the slider (62) and that pins (64) are provided extending into the recesses (72), on each pin being supported a slider (62), respectively.

9. The conveyance device in accordance with claim 7 or 8, characterized in that a cam disk (70) is provided, the cam disk being fixed on the journal of the sprocket wheel (10) and comprising the keyway (71) on the surface thereof.

10. The conveyance device in accordance with one of the claims 1 to 9, characterized in that the fixed and the movable clamping members (13, 15) comprise side portions (134, 135 ; 154, 155), respectively, the side portions (154, 155) of one clamping member (15) comprising a slotted hole (158), and the side portions (134, 135) of the other clamping member (13) comprising pins (136,137) being guided in the slotted hole (158).

11. The conveyance device in accordance with claim 10, characterized in that the clamping carrier (12) comprises a joint by cooperating of the pins (136, 137) in the side portions of the fixed clamping member (13) with the slotted holes (158) in the side portions (154, 155) of the movable clamping member (15).

12. The conveyance device in accordance with claim 10 or 11, characterized in that a pin (152) being fixedly connected to the movable clamping member (15) is provided, the pin being arranged substantially parallel to the slotted holes (158) and being guided in a bushing (133) cooperating with the fixed clamping member (13).

13. The conveyance device in accordance with claim 12, characterized in that the bushing (133) is fixedly connected with the fixed clamping member (13).

14. The conveyance device in accordance with claims 12 or 13, characterized in that the pin (152) is emersed from the bushing (133) in the open position.

15. The conveyance device in accordance with one of claims 12 to 14, characterized in that the movable clamping member (15) is only movable in a plane parallel to the plane of the sprocket wheel during the first section of the lifting and is additionally tiltable with respect to this plane in a following second section.

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