EP0445429A1 - Packaging station for a packaging machine, in which a stack of articles is tied with a tying strap - Google Patents

Abstract

A packaging machine in which a stack of goods (1) is strapped with a packaging band (2) has a work table (19) with a turntable (18) which consists of individual sectors. These are at a distance (46) from one another diametrically to the axis of rotation (39), one of which is located above a guide channel (44) for the packaging tape (2). In addition, devices are provided for lowering a transport device (1o) from the area of the turntable (18). These measures make it possible to strap a stack of goods (1) with a plurality of packaging straps (2) crossing one another in a packaging station. <IMAGE>

Description

The invention relates to a packaging station according to the preamble of claim 1.

Packing stations of this type are primarily used for strapping magazine stacks with an elastic packaging band made of plastic, which is stretched and the ends of which are welded together. In packaging stations of this type, a work table is provided which has a guide channel which can be opened toward the stack of goods and which is supplemented laterally above the work table and above this to form a closed guide path, these regions of the guide path located above the work table being formed in a guide frame. In the transport direction, transportable drive belts are provided in front of and behind the guide channel for the packaging belt, by means of which a stack of goods is transported centrally over the guide channel or, after being strapped with a packaging belt, is transported further in the transport direction. If a stack of goods is to be strapped with packaging tapes crossing one another, then the stack of goods strapped with a packaging tape is placed in a first packaging station downstream turntable rotated by 90 degrees and then transported to a similar second packaging station. This known configuration requires two corresponding packaging machines and an intermediate rotating device, which is disadvantageous in terms of equipment and the space required.

The invention has for its object to design a packaging station so that a stack of goods can be strapped in it with several intersecting packaging tapes.

This object is achieved according to the invention in a packaging station of the generic type by the features in the characterizing part of claim 1. The essence of the invention is that the stack of goods in the packaging station is rotated after strapping with a first packaging tape and then strapped with a further packaging tape, it being possible in principle to provide three or more strapping. Usually, however, two straps are sufficient, ie the stack of goods is rotated 90 ° between the strapping processes. To enable the turntable to be turned, the transport device can be lowered. The design with the sectors forming the turntable has the result that in each rotational position of the turntable provided for a strapping process, the guide channel for the packaging tape to the good stack is completely open, so that the packaging tape after welding to the Create a good stack can and the stack of goods can be transported further.

Claim 2 specifies a particularly simple type of storage for the sectors of the turntable. Claim 3 reproduces in a particularly simple manner how, when driving only one sector, the other sectors each participate in the preferred reciprocating rotary movement, although it is nevertheless ensured that the guide channel is in each case exposed to the stack of goods.

Claim 4 specifies a particularly simple embodiment of the respective driver device, claim 5 reproducing structural details on this. Claim 6 gives the details of an unlocking device for the driver devices.

The development according to claim 7 specifies how the transport device is brought out of the turntable in order to enable its rotations. The claims 8 to 1o indicate the constructive advantageous embodiments for this.

Fig. 1

eine Verpackungsmaschine mit einer Verpackungsstation nach der Erfindung in schematischer perspektivischer Darstellung,

Fig. 2

einen Querschnitt durch die Verpackungsstation, der hauptsächlich die Transporteinrichtungen zeigt,

Fig. 3

eine Draufsicht auf den Arbeitstisch der Verpackungsstation und

Fig. 4

eine Mitnehmereinrichtung und eine Entriegelungsvorrichtung in vergrößertem Maßstab.

Further details, advantages and features of the invention result from the following description of an embodiment of the invention with reference to the drawing. It shows

Fig. 1

a packaging machine with a packaging station according to the invention in a schematic perspective view,

Fig. 2

a cross section through the packaging station, which mainly shows the transport devices,

Fig. 3

a plan view of the worktable of the packaging station and

Fig. 4

a driver device and an unlocking device on an enlarged scale.

A packaging machine, in which only good stacks 1 indicated in FIG. 2, which are preferably magazine stacks, are strapped with a packaging band 2, have a lower, approximately cuboidal machine frame 3 and a machine frame arranged thereon Packing station 4 on. A supply roll 5 is attached to the side of the frame 3, pulled off the packaging tape 2 and shot into the packaging station 4 by means of a so-called shooting device 6, loosely enveloping a stack of goods 1. The insertion device 6 consists of a pair of rollers 7 which can be driven at high speed and a drive motor (not shown in the drawing). By reversing the direction of rotation of the pair of rollers 7, the band 2, the free end of which is held in the packaging station 4, is pulled back against the insertion direction 8 until it lies against the stack of goods 1. When the band 2 is shot in, it is guided in a guide track which is formed in a guide frame 9 mounted on the frame 3 and is only indicated in the drawing. Such a packaging station, as described so far, is generally known in practice and is widely used.

On the machine frame 3, on the one hand a transport device 1o for transporting a stack of goods 1 in the transport direction 11 through the packaging station 4 and on the other hand a rotating device 12 for rotating a stack of goods 1 by 90 ° in the direction of rotation 13 is provided around the stack of goods 1 to be strapped in only one packaging station 4 in two directions with a packaging tape 2.

The rotating device 12 has a turntable 18 formed from four quarter-circular plate-shaped sectors 14, 15, 16, 17, which is explained in more detail below. The turntable 18 is arranged in a work table 19 which is arranged on the frame 3. The work table 19 and the sectors 14 to 17 have recesses 20, 21 which are each assigned to one another in pairs and which extend in the transport direction 11, as can be seen in particular in FIG. 3.

The transport device 10 has a total of four conveyor belts 22, two of which are arranged parallel to one another and two in each case one behind the other in the transport direction 11. They are guided around drive rollers 23 mounted on the frame 3, which are driven by a common drive motor 24 arranged in the frame 3 by means of a common drive belt 25 which, as can also be seen in FIG. 2, is guided over a deflection roller 26 arranged in the frame 3.

Each of the two conveyor belts 22 arranged parallel to one another and assigned to a drive roller 23 are guided over a series of deflection rollers 27 which are freely rotatably mounted in a pivotable frame 28. They are guided over these deflection rollers 27 in such a way that a transport section 29 projects through the corresponding recess 2o in the work table 19 and another transport section 3o through the corresponding recess 21 in the corresponding sector 14, 15, 16 or 17 of the turntable 18, such as it is particularly indicated on the left in FIG. 2. The corresponding transport section 29 or 3o in this case protrudes slightly beyond the top of the work table 19 or the turntable 18.

Each pivotable frame 28 is pivotable about the axis 31 of the corresponding drive roller 23. For this purpose, it is provided with a base plate 32 to which a downwardly extending actuating arm 33 is fastened, at the lower end of which a piston rod 34 of a piston-cylinder drive 35 which can be acted upon hydraulically or pneumatically is articulated by means of a joint 36. The cylinder 37 of the corresponding piston-cylinder drive 35 is in turn articulated on an abutment 38 of the frame 3. In the retracted position of the piston rod 34, the frame 28 with the corresponding conveyor belt 22 is in its swiveled-up transport position shown on the left in FIG. 2, in which the transport sections 29, 33 through the corresponding recesses 20, 21 over the top of the work table 19 or of the turntable 18 protrude. In the extended position of the piston rod 34, the corresponding conveyor belts 22 with the pivotable frame 28 are located in the pivoted down position shown in FIG. 2 on the right Position in which the transport sections 29, 33 are located below the top of the turntable 18 and the work table 19, in which they can therefore not force a transport movement in the transport direction 11 onto a stack of goods 1, which is located on the turntable 18, and in which in particular cannot hinder rotations of the turntable 18.

The four sectors 14, 15, 16, 17 of the turntable 18 are guided on the one hand on their outer circumference in a guide groove 4o of the work table 19 arranged concentrically to the axis of rotation 39 of the turntable 18. They are also guided on their side adjacent to the axis of rotation 39 in a corresponding guide groove 42 which is also arranged concentrically to the axis of rotation 39. This guide groove 42 is formed in a central part 43 of the work table 19 which is stationary and rotatable relative to the machine frame 3.

Below the work table 19, below the sectors 14 to 17 and below the fixed middle part 43, an upwardly opening guide channel 44 for the packaging tape 2 is formed, which runs transversely to the transport direction 11 and through which the packaging tape 2 after passing through Guide path in the guide frame 9 is shot in the direction 8. The guide channel 44 in the area of the turntable 18 can be completely open upwards, inter alia, by virtue of the fact that the sectors 14 to 17 — as can be seen in particular from FIG. 3 — are arranged with a distance 46 or 46 ′ from one another, leaving a distance. The four sectors 14 to 17 are connected to one another via driver devices 47, 47 ', so that when a sector 14 is pivoted in the direction of rotation 13 by an angle of rotation 48 of 90 °, the distance 46 or the distance 46 'alternates via the guide channel 44.

The rotary drive 49 for the turntable 18 is a linear drive designed as a hydraulically or pneumatically actuated piston-cylinder drive, the cylinder 50 of which is articulated on the machine frame 3 by means of a joint 51, and the piston rod 52 of which is articulated on the underside of a sector 14 53 is attached. If the piston rod 52 is extended from the cylinder 50 as shown in FIG. 3, then the distance 46, which is delimited on one side by the sectors 14, 15 and on the other side by the sectors 16, 17, is over the guide channel 44. On the other hand, when the piston rod 52 is retracted into the cylinder 50, the sector 14 - in FIG. 3 clockwise - is pivoted by the angle of rotation 48, the other three sectors 15, 16, 17 being carried along. As a result, the distance 46 ′, which is delimited between the sectors 17, 14 on one side and the sectors 15, 16 on the other side, passes through the guide channel 44. When the piston rod 52 is extended again, all four sectors 14 to 17 become again - in Fig. 3 counterclockwise - pivoted back into the position shown in Fig. 3. For this reason, the direction of rotation 13 is marked with a double arrow.

In principle, the driver devices 47, 47 'are of identical design; the driver devices 47 and 47 'associated with a distance 46 and 46' are only constructed mirror-symmetrically to one another, as can be seen in FIG. 3. It will therefore only be one in Fig. 4 enlarged driver device 47 described. It has a pawl 55 which can be pivoted on the underside of a sector 16 about a swivel joint 54 and which is pulled against a stop 57 attached to the same sector 16 by means of a pretensioned tension spring 56 also fixed on the underside of the corresponding sector 16. In this rest position, which can be referred to as the driver position, it rests with an end face 58 against a driver stop 59 which is formed on the adjacent sector 15. If all four pawls 55 are in their rest position as described, then all four sectors 14 to 17 are at the distance 46 and 46 'to one another as described.

Two unlocking devices 6o are arranged in the machine frame 3 and are assigned to the two driver devices 47, 47 'which fix the distance 46 or 46' just above the guide channel 44. 3, these two unlocking devices 6o are thus arranged below the sectors 16, 17. They have a pivotable unlocking lever 61 which is pivotally mounted in the machine frame 3 about a fixed pivot bearing 62. The unlocking lever 61, which is designed as a two-armed lever, has an unlocking pin 63 at one end, which, when the unlocking lever 61 is pivoted, can be pivoted about the pivot bearing 62 against a contact surface 64 of the pawl 55, as a result of which this counteracts the force of the tension spring 56 - in FIG. 4 in Counterclockwise - from the system against the driver stop 59 and the stop 57 can be pivoted out in such a way that the section 65 of the pawl 55 bridging the distance 46 is pivoted out of the area of the distance 46.

To pivot the unlocking lever 61, an unlocking drive 66 serving as a hydraulically or pneumatically actuated piston-cylinder drive is provided, the cylinder 67 of which is articulated on the machine frame 3 by means of a joint 68 and the piston rod 69 of which on the end of the unlocking lever 61 opposite the unlocking pin 63 attacks the latter. When the piston rod 69 is extended, the unlocking pin 63 is outside of an attack on the pawl 55. When the piston rod 69 is retracted, the pawl 55 is pivoted out of its driving position shown in FIG. 4 and releases the distance 46.

A welding unit 7o for the packaging tape 2 is arranged below the middle part 43, which serves as a turntable guide, which is assigned to the guide channel 44 in this area and which is part of a welding device 71 arranged in the machine frame 3. Details of the welding device 71 with the welding unit 7o are not shown and are not explained, since they are common in so-called strapping machines or packaging machines in which material stacks 1 are strapped with a plastic packaging tape 2.

If a stack of goods 1 has moved onto the turntable 18 in the transport direction 11, then the shoot-in device 6, a packaging tape 2, the end of which is previously located in the area of the welding unit 7o, that is to say below the middle part 43, is guided around the outside of the stack of goods 1, it being guided in the guide track in the guide frame 9. From there it slides into the guide channel 44 in the shooting-in direction 8 and is held in the welding unit 7o. Then the packaging tape 2 is tensioned by reverse driving the pair of rollers 7 of the insertion device 6. Here, the guide track in the guide frame 9, on the one hand, and the guide channel 44 below the work table 9 are opened, so that the packaging tape 2 can emerge from the guide and lay around the stack of goods 1. These devices for opening the guideway and the guide channel 44 are generally customary and known in practice. As a result of the tensioning, the band 2 is stretched around the stack of goods 1, whereby - as can be seen in particular from FIG. 2 - it does not rest on the underside of the stack of goods 1, but is stretched downwards to the welding unit 7o. Since such packaging tapes 2 consist of elastic, weldable plastic, this is easily possible. The strip 2 is then welded and cut off in the welding unit 7o. The strapping process described up to this point is known and generally customary. In this strapping process, the two driver devices 47, 47 ', which are located in the region of the guide channel 44, are removed from their driver position.

Then these two driver devices 47, 47 'are brought back into their driver position, in which the unlocking devices 6o are pivoted into their inoperative position, which is shown in FIG. 4. For transporting the stack of goods 1 on the turntable 18 and possibly also during the strapping process, the transport devices 10 are in their swiveled-up position shown on the left in FIG. 2.

Before the turntable 18 is pivoted by the rotary drive 49 by the angle of rotation 48 of 90 °, the transport devices 10 are pivoted into their pivoted-off position shown on the right in FIG. 2. For this purpose, the piston-cylinder drives 35 serving as a linear drive are acted upon in such a way that the piston rods 34 extend, as a result of which the pivotable frames 28 with the conveyor belts 22 are pivoted downward, so that the transport sections 3o out of the recesses 21 in the sectors 14 to 19 swing out downwards. Then the rotary drive 49 is acted on, so that the turntable 18 is pivoted by the angle of rotation 48. In this position, the unlocking devices 6o are actuated again, so that the driver devices 47, 47 ', which now bridge the distance 46' above the guide channel 44, are opened. Then a strapping process already described takes place again. The transport devices 10 can already be pivoted back into their swiveled-up transport position. However, they can also be swiveled up only after the strapping process has been completed. Then they are driven by actuation of the drive motor 44, so that the double with a packaging tape 2 strapped stack of goods 1 is moved out of the packaging station 4 of the packaging machine. At the same time, a new stack of goods 1 is already being moved into the packaging station 4. Due to the described alternate rotation of the turntable 18 in the opposite direction, the good stacks 1, which always arrive in the same order and direction beforehand, are each rotated alternately by 180 ° from the packaging station 4. In the case of magazine stacks which fold the folds on one side, that is, the folds of the paper layers, this has the advantage that they can then be stacked more easily, since magazine stacks are thicker on the side of the fold than on the opposite side.

Claims (10)

Packing station of a packaging machine, in which a stack of goods (1) is strapped with a packaging tape (2), with a work table (19) for receiving a stack of goods (1), with a transport device (1o) for transporting a good -Stacks (1) in a transport direction (11) in a strapping position and out of this position and with a guide device (guide frame 9 and guide channel 44) for guiding the packaging tape (2) around the stack of goods (1) in a shooting direction (8) transversely to the transport direction (11), the work table (19) being provided with a guide channel (44) which can be opened to the stack of goods (1) and runs transversely to the transport direction (11), characterized in that the work table (19) is at least partially formed by a turntable (18) which can be driven in rotation about an axis of rotation (39) and which consists of at least four sectors (14 to 17) which have at least two distances (46, 46 ') running diametrically to the axis of rotation (39). to each other iron, one of which is located above the guide channel (44), and that devices are provided for lowering the transport device (1o) from the area of the turntable (18). Packing station according to Claim 1, characterized in that the sectors (14 to 17) are mounted in guides (guide grooves 40, 42) of the work table (19) which are formed concentrically to the axis of rotation (39). Packing station according to claim 1, characterized in that only one sector (14) can be driven in rotation and that the sectors can be moved by means of driver devices (47, 47 ') bridging the distances (46, 46') and moving out of the area of the distances (46, 46 '). ) are coupled together. Packing station according to Claim 3, characterized in that each driver device (47, 47 ') has a pawl (55) which is pivotably mounted on a sector (14 to 17) and which, in a driver position, is at a distance (46) from an adjacent sector ( 15) bridging section (65) bears against a driver stop (59) on the adjacent sector (15) and which can be pivoted out of this driver position by means of an unlocking device (6o) in such a way that the section (65) no longer bridges the distance (46) . Packing station according to claim 4, characterized in that the pawl (55) rests with a prestressed spring (56) in its driving position against a stop (57) which is located on the sector (16) carrying the pawl (55). Packing station according to claim 4, characterized in that the unlocking device (6o) has a two-armed unlocking lever (61) mounted in a fixed pivot bearing (62), at one end an unlocking drive (66) engages and the other end with the pawl (55 ) can be brought into unlocking engagement. Packing station according to Claim 1, characterized in that the transport device (1o) has at least one drivable transport belt (22) arranged in front of and behind the guide channel (44) in the transport direction (11), at least one transport section (3o) of which through a recess ( 21) projects in a sector (14 to 17) to the side of the stack of goods (1) which can be moved out of the sector (14 to 17) from the side of the stack of goods (1). Packing station according to claim 7, characterized in that two transport belts (22) are arranged on each side of the guide channel (44) in the transport direction (11), of which one transport section (3o) each in a recess (2o) of a sector (14 to 17) is arranged. Packing station according to claim 7 or 8, characterized in that a conveyor belt (22) is mounted on a pivotable frame (28) by means of deflection rollers (27) which can be pivoted out of the turntable (18). Packing station according to claim 9, characterized in that a conveyor belt (22) can be driven by means of a drive roller (23) which can be driven in rotation about a stationary axis (31), and in that the pivotable frame (28) can be pivoted about the axis (31).

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