EP0532947A1 - Method and device for conveying and closing packages - Google Patents

Abstract

A method and a device for sealing packages is specified, in which packages which are preferably in the form of bags are moved forwards between an upper belt (16) and a lower belt (12). The distance between the upper belt (16) and the lower belt (12) is adjusted to the height (h) of a package (18, 18%) by a slewing belt (14) which is rotatably connected to the upper belt (16) by means of its rear end (13), seen in the direction of transport, and which projects obliquely upwards from the upper belt (16) in the direction of incoming packages (18, 18%). The upper belt (16) and the slewing belt (14) are held for example in a suspended manner by spring elements (22, 24), so that both can escape upwards, when the slewing belt is horizontally aligned, by means of the slewing belt (14) which initially rests obliquely on the package (18, 18%), until the slewing belt (14) rests horizontally on the top of the package (18, 18%) and the upper belt (16) is therefore adjusted to the height of the package. <IMAGE>

Description

The invention relates to a method for transporting and closing packaging, in which the packaging is advanced between at least one upper band and at least one lower band and then closed by fastening a closing part.

The invention further relates to a device suitable for carrying out the method.

After a piece of packaging has been inserted into a bag-shaped packaging, it is closed in a conventional manner after a closing part, which is usually designed as a tab, is folded down by pressing the self-adhesive closing part onto the outside of the packaging.

In addition, closing by sticking a self-adhesive label is also common.

After the packaging has been filled, it can be transported between a lower belt and an upper belt to the clamping unit, where the packaging is closed.

Since the packaging height is determined by the distance between the upper belt and lower belt, the distance between the upper belt and lower belt must be readjusted if the height of the packaging changes when the type of packaging is changed.

Manual adjustment of the distance between the upper belt and lower belt is mechanically complex and time-consuming. Furthermore, the risk of incorrect settings is not excluded, which can damage the packaging or the contents of the packaging. Additional disadvantages arise from differences in the height of the packaging within a batch. While the packaging and its contents can be deformed at a higher height, there is a risk that a lower height of the packaging will not ensure proper transport, so that there may be a jam in the packaging machine.

In addition, methods and devices for packaging are known in which an automatic adjustment is made to the height of the packaging, but here the transport route and the speed, i.e. the number of cycles per minute, limited by the masses to be moved. In such arrangements, the function of different units must also be coordinated.

The present invention is accordingly based on the object of providing a method and a device for transporting and closing packaging, with which reliable function is ensured in a simple manner even when the height of the respective packaging changes frequently.

This object is achieved in that, in a method of the type mentioned, the distance between the upper belt and lower belt is set by a swivel belt protruding from the upper belt against the direction of transport, for which purpose the upper belt and the swivel belt are spring-loaded before the packaging is brought into a lower basic position be held in suspension, and the swivel belt with its front end, viewed in the direction of transport, is initially placed obliquely upwards, whereupon the swivel belt is aligned horizontally when a package is fed up to a predetermined distance from the swivel belt, whereby the one-sided on the packaging to the system coming swivel band is lifted until the swivel band lies horizontally on the top of the packaging and at the same time the top band is adjusted to the height of the packaging.

With regard to the device, this object is achieved according to the invention in that, in a device of the type mentioned at the outset, the upper belt is vertically movable parallel to the lower belt against a spring force, in that a swivel belt is provided which, viewed in the direction of transport, has a rear end that is rotatable with the upper belt is connected and with its, seen in the direction of transport, front end can be adjusted obliquely upwards by means of a lifting cylinder, that the swivel band and the upper band are kept somewhat suspended by at least one spring element, whereby they are acted upon with a low vertical force, and that the swivel band is above the lifting cylinder can be aligned horizontally in order to adjust the distance of the swivel belt, which initially lies obliquely against the packaging, and of the upper belt from the lower belt to the height of the packaging.

According to the present invention, the upper belt is set to a distance from the lower belt which is predetermined by the height of the respective packaging, by means of the swivel belt which projects obliquely upwards in the direction of the incoming packaging. Before the packaging is brought in, the upper belt is held in a lower basic position by the spring force and the swivel belt is tilted upwards.

Now the lifting cylinder is acted on so that the swivel belt moves downward with its end protruding counter to the transport direction. The inclined swivel belt thus comes to rest on the rear edge of the packaging, as seen in the transport direction, whereupon the swivel belt carries out a rolling movement on this edge, the front one The end of the swivel belt is moved down and the rear end of the swivel belt is moved up until the swivel belt lies horizontally on the top of the packaging and the upper belt is adjusted to the height of the packaging.

The automatic adjustment of the top belt prevents incorrect settings and compensates for differences in the height of individual packaging. Likewise, the floating suspension eliminates the risk of damage to the packaging or the contents of the packaging as a result of incorrect settings. In this way, a malfunction is effectively avoided even in fully automatic continuous operation.

Since the swivel belt adjusts itself to the incoming packaging at an early stage, timely adjustment of the vertical position of the top belt to the height of the packaging is guaranteed. Since considerable inertial forces can occur during the parallel displacement of a conveyor belt, the adjustment speed and thus also the packaging speed is limited. Since the swivel belt is only pivoted with its front end and the rear end gradually contacts the packaging, disadvantages due to inertia are compensated for. The consequence of this is that the packaging speed can be increased considerably compared to conventional processes.

In a development of the method according to the invention, the lower belt, the upper belt and the swivel belt are stopped as soon as an incoming packaging has reached a predetermined distance from the swivel belt. The lower band, upper band and The swivel belt is then switched on again to advance the packaging as soon as the swivel belt is aligned horizontally and the swivel belt and top belt are adjusted to the height of the packaging.

This measure has the advantage that the packaging cannot move laterally during the adjustment movement of the swivel belt and the upper belt. The forces acting on the packaging are also kept particularly low in this way. Since the device operates intermittently due to the integrated clamping unit, the processing speed is not adversely affected thereby.

After the packaging has been transported between the horizontally set swivel belt and the lower belt to the subsequent upper belt, the swivel belt is again inclined upwards in order to enable the arrangement to be adjusted to the height of a subsequent packaging.

In a further development of the device according to the invention, the swivel belt and the upper belt form a continuous belt, the swivel belt being designed as a pivotable belt part of the upper belt projecting from the upper belt in the opposite direction of transport.

By forming the upper belt and swivel belt as a common belt, an additional drive for the swivel belt is superfluous and the structure of the arrangement is considerably simplified.

In a further development of the invention, the upper belt is guided vertically displaceably via at least one vertical support, and the swivel belt is held at its second end via the lifting cylinder, which engages one of the vertical supports at a fixed distance from the upper belt.

This measure has the advantage that both ends of the swivel belt are coupled to the upper belt, so that with a vertical displacement of the rear end of the swivel belt and thus also of the upper belt, the front end of the swivel belt is simultaneously shifted vertically by a corresponding amount.

In a further embodiment of the invention, a control device is provided which emits a switching signal to a switching valve for the lifting cylinder in order to incline the swivel belt before the arrival of a package, which further emits a switching signal when a predetermined distance between the incoming packaging and the swivel belt is reached, in order to To stop the upper belt, the swivel belt and the lower belt and to switch the switching valve for the horizontal alignment of the swivel belt, and which emits another switching signal to put the upper belt, the swivel belt and the lower belt into operation again after the swivel belt has been aligned horizontally.

If a package reaches a predetermined distance from the swivel belt, the belts are stopped by the control device and the lifting cylinder, which is preferably designed as a double-acting pneumatic cylinder, is activated until the swivel belt and upper belt have adjusted to the height of the packaging, whereupon the belts be put back into operation via the control device.

Once the swivel belt and the upper belt are set to the height of the respective packaging, the packaging is advantageously between the lower belt and a continuous tread on the top, which is through the upper belt and the upstream, horizontally aligned swivel belt is formed, transported.

In a further embodiment of the invention, the spring force of the spring elements is largely independent of the spring travel.

This prevents the restoring force from changing as a function of the spring travel. This ensures that regardless of the height of the packaging, the contact pressure of the upper belt on the top of the packaging is largely constant.

One way to achieve such a spring characteristic is to design the spring elements as gas pressure springs. In addition, however, other configurations, e.g. possible in the form of mechanical springs.

In an advantageous development of the invention, the spring force of the spring elements is adjustable.

This has the advantage that the spring force can be matched to the rigidity of the packaging and the sensitivity of the packaged goods.

In a further embodiment of the invention, the clamping unit is fastened to a holder which can be moved in the vertical direction together with the upper belt.

In this way it is ensured that the distance between the clamping unit and the packaging is kept constant regardless of its height. This ensures that the function of the clamping unit is independent of the packaging height and uniform work is guaranteed. Thus, even with different packaging heights, a secure closure of the packaging is guaranteed and damage due to excessive pressing due to different distances from the packaging is avoided. Likewise, the even contact pressure ensures a perfect seal, so that poorly sealed packaging is avoided.

In a further embodiment of the invention, a guide plate extending in the feed direction of the lower belt is provided for the vertical installation of a closing part which projects laterally from a package.

As a result, the closing part is brought into a suitable position during the feed movement in order to be closed by means of the closing unit arranged below.

In an additional development of the invention, the closing unit has a hold-down device for holding down the top of the packaging, a side slide for folding the closing part over the hold-down device and a vertically movable closer for closing the packaging from above.

Since these known devices are fastened according to the invention to a holder which can be moved together with the upper band in the vertical direction, it is ensured that the hold-down device, regardless of the height of the packaging, holds the top thereof down uniformly, the side slide always correctly with respect to the closing part is positioned and the closer presses the closing part onto the top of the packaging with an even contact pressure.

It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own without departing from the scope of the present invention.

Fig. 1a

eine Funktionsskizze einer erfindungsgemäßen Vorrichtung in stark vereinfachter, schematischer Darstellung in einer ersten Bewegungsphase;

Fig. 1b

eine Darstellung gemäß Fig. 1a, jedoch in einer zweiten Bewegungsphase, in der sich das Schwenkband an die Oberseite der Verpackung angelegt hat;

Fig. 1c

eine Darstellung gemäß Fig. 1b, jedoch in einer dritten Bewegungsphase, in der die Verpackung das Schwenkband bereits passiert hat und zur Schließeinheit gelangt ist und

Fig. 2

eine perspektivische Ansicht der Vorrichtung gemäß den Fig. 1 bis 1c in leicht abgewandelter Ausführung und in vereinfachter Darstellung.

Preferred exemplary embodiments of the invention are shown in the drawing and are explained in more detail in the description below. Show it:

Fig. 1a

a functional sketch of a device according to the invention in a highly simplified, schematic representation in a first movement phase;

Fig. 1b

a representation of Figure 1a, but in a second phase of movement, in which the swivel band has placed itself on the top of the package.

Fig. 1c

a representation according to FIG. 1b, but in a third movement phase, in which the packaging has already passed the swivel belt and has reached the closing unit and

Fig. 2

a perspective view of the device according to FIGS. 1 to 1c in a slightly modified version and in a simplified representation.

A packaging device, designated as a whole by the number 10, has three driven belts according to FIGS. 1a-1c, a lower belt 12, an upper belt 16 and a swivel belt 14 connected to the upper belt 16. The swivel belt 14 forms together with the upper belt 16 a continuous belt driven by a common drive. The swivel belt 14 is designed as a pivotable component of the upper belt 16 which projects from the upper belt 16 in the opposite direction of transport. The connection between the rear end 13 of the swivel belt 14 and the upper belt 16 forms a common deflection roller between the two belts.

A package 18 to be closed lies on the lower belt 12 and is moved forward by this in the transport direction, which is indicated by the arrow 34.

A stationary support 38 running parallel to the upper belt 16 is attached to the machine frame 36. The upper belt 16 is guided in a vertically displaceable manner on the carrier 38 via two parallel vertical supports 48, 50. The vertical beams 48, 50 are rigidly connected to a longitudinal beam 40 parallel to the upper band 16. Two spring elements 22, 24, which are designed as adjustable gas pressure springs (pneumatic cylinders with throttle valve), are arranged between the longitudinal beam 40 and the fixed beam 38.

The front end 15 of the swivel belt 14 projects from the upper belt 16 counter to the direction of advance and is at its front end 15 via a lifting element, which is designed as a pneumatic lifting cylinder 64, at a fixed point of application 17 of the vertical support 48 arranged on the side of the swivel belt 14 held.

In the position shown in FIG. 1a, a pack 18 to be closed lies on the beginning of the lower belt 12. Since the packaging 18 does not touch the projecting swivel belt 14 or the upper belt 16, the arrangement formed by the upper belt 16 and the swivel belt 14 is located in FIG a lower vertical basic position, which is predetermined by the lowest position of the vertical supports 48, 50 in the vertical guides 49, 51 or by the maximum extension length of the gas pressure springs.

The pneumatic lifting cylinder 64, which is designed as a double-acting lifting cylinder, is acted upon in this position in such a way that the swivel belt 14 is inclined upwards. The gas pressure springs are set so that even a small upward force is sufficient to move the swivel belt 14 and the upper belt 16 from the basic position upwards.

If, according to FIG. 1b, a package 18 is transported on the lower belt 12 up to a predetermined distance from the swivel belt 14, the swivel belt 14, upper belt 16 and lower belt 12 are stopped and the lifting cylinder 64 is extended. As a result, the swivel belt 14 comes into contact with its running surface 19 on an edge of the packaging 18. As the lifting cylinder 64 is extended further, the front end 15 of the swivel belt moves downward, while the rear end 13 of the swivel belt 14 moves upwards on the edge of the packaging 18. The swivel belt thus rolls with its tread 19 on the packaging 18 until the swivel belt 14 lies horizontally on the top of the packaging 18 and the upper belt 16 connected to the swivel belt 14 has thus adjusted to the height of the packaging. The extension length of the lifting cylinder 64 is dimensioned such that the swivel belt 14 can only pivot out into the horizontal position, but not further.

The belts are now put into operation again, and the packaging 18 is transported further in the direction of arrow 34 between the swivel belt 14 and the lower belt 12 or between the subsequent upper belt 16, now aligned in its vertical position, and the lower belt 12. Finally, the package 18 is closed by a closing unit 30 indicated by a broken line in FIG. 1c, for which purpose the upper band 16 and the lower band 12 are stopped. The closing unit 30, the individual components of which can be seen in more detail in FIG. 2, can be lowered onto the packaging 18 together with the upper belt 16.

This has the consequence that the distance between the top of the package 18 and the closing unit 30 is always set consistently due to the vertical orientation of the upper belt 16, which ensures a constant function.

After a package 18 has been transported between the swivel belt 14 and the lower belt 12 to the subsequent upper belt 16, the lifting cylinder 64 is switched over again, so that the swivel belt 14 is again inclined upwards and can be aligned with the next incoming package.

Details of the structure of the packaging device according to the invention can be seen in more detail in FIG. 2. This device differs from the device according to FIG. 1 only in that the upper belt 16 and the swivel belt 14 consist of two separate belts which are rotatably connected to one another are. For the rest, the structure of the two versions is completely identical. In Fig. 2 movable connections or guides between round bars and beams are indicated by a circle or ellipse drawn around the respective bar at a distance. As already explained, the upper belt 16 is rigidly connected to the two vertical supports 48, 50, which are vertically displaceable in the vertical guides 49, 51 of the fixed support 38. The swivel belt 14 fixed at its rear end 13 to the upper belt 16 is held at the front end 15 via the lifting cylinder 64, the lifting cylinder 64 being fixed to a mounting plate 65 which is fastened to the second vertical guide 49 below the fixed support 38.

A control device 66 for controlling the feed movements of the belts and the lifting cylinder 64 is indicated by the number 66. The double-acting lifting cylinder 64, which is designed as a pneumatic cylinder, is controlled by the control unit 66 via a switching valve 60. Furthermore, a sensor 58 is arranged on the lifting cylinder 64, which emits a switching signal to the control device 66 as soon as the lifting cylinder 64 has been fully extended, and thus the swivel belt 14 is aligned horizontally.

The longitudinal beam 40 is rigidly connected to the two rod-shaped vertical beams 48, 50. The spring elements 22, 24 in the form of gas pressure springs are arranged between the longitudinal beam 40 and the fixed beam 38, as has also already been explained.

A bracket 52 projecting at right angles is also arranged on the fixed support 38, two at its free end parallel guide rods 54, 56 extending in the vertical direction are fixed. These guide rods 54, 56 are used for vertical guidance of the closing unit, designated overall by the number 30, which is fastened to a holder 42 on the side member 40. The bracket 42 is rigidly connected to the side member 40. Starting from the holder 42, a vertical support 44 extends downward, to the lower end of which a hold-down 32 protruding horizontally in the direction of advance is fastened. The bracket 42 is guided on the two guide rods 54, 56 of the boom 52 in the vertical direction. In addition, a guide plate 46, which is also guided on the two guide rods 54, 56, is fixed at right angles to the vertical support 44 which extends downward from the holder 42. An additional gas pressure spring 23 is arranged between this guide plate 46 and the arm 52.

On the bracket 42, a closer 26 is also attached, which has a pneumatically movable rod with a horizontal closing plate 27 at the lower end. At the lower end of the vertical support 44 projecting downward from the holder 42, an angle support 53 is also attached, to which a side slide 28 is attached, the slide plate 29 of which can be moved pneumatically in the direction of the side wall of a package.

The closing unit 30, which consists of the slide 28, the closer 26 and the hold-down 32, can thus be moved together with the upper belt 16 in the vertical direction.

If a package arriving on the lower belt 12 reaches a predetermined distance from the inclined swivel belt 14, the swivel belt 14, the upper belt 16 and the lower belt 12 are stopped via the control unit 66, and the lifting cylinder 64 is extended via the switching valve 60, so that the swivel belt is lowered with its front end 15 downward until the swivel belt 14 with its tread 19 on the rear edge of the packaging 18 seen in the transport direction comes to rest and now, when the lifting cylinder 64 is extended further, the rear end 13 of the swivel belt 14 together with the upper belt 16 are raised until the swivel belt 14 with its tread 19 lies horizontally on the Has created top of the package 18.

In this way, the swivel belt 14 and the subsequent upper belt 16 automatically adjust themselves to a height h of the packaging.

The belts are now put into operation again via the control unit 66, and the packaging 18 is transported between the upper belt 16 and the lower belt 12 in the direction of the arrow 34 until it reaches the position on the closing unit 30 indicated by the number 18 '.

The packaging 18 is bag-shaped in the example shown and has a laterally projecting closing part 20 in the form of a flap which has to be folded upwards to close and must be pressed onto the top of the packaging. In order to fold up the closing part 20 into a vertical position, a guide track 62 with an oblique guide surface is arranged in the longitudinal direction of the lower belt 12, on which the closing part 20 rests and during the feed movement into the position at the Closing unit is erected upwards by the rising guideway 62. In the position of the package 18 'shown on the closing unit 30, the closing part 20 has been moved upwards and has been folded over onto the top of the package by the slide 28 which moves towards the side. The top of the package is additionally held down by the hold-down 32 in the position shown. In the folded-down position, which is indicated by the number 20 ', the closing part is finally pressed onto the top of the packaging by moving the closer 26 over its closing plate 27 with a front self-adhesive layer and thus glued.

In an alternative embodiment, the closure can also be done by sticking on a self-adhesive label.

The fact that the entire clamping unit 30 is adjusted to the height h of the packaging together with the upper belt 16 ensures that the clamping unit functions reliably. In particular, it is avoided that the packaging or its contents are damaged by excessive pressure or that the packaging is not completely closed.

In the case of a further feed movement, the packaging is finally moved out of the closed position, the hold-down 32 being gradually pulled out from under the closing part 20 'which is already glued to the front end.

After each pass through a package 18, the swivel belt 14 is again inclined upwards via the lifting cylinder 64. The distance between the swivel belt 14 is then subsequently established and the upper belt 16 again automatically to the level of a subsequent package 18.

It goes without saying that the terms used above are to be understood as not restricting horizontally and vertically, so that the entire packaging device can also be used in a slightly inclined position.

Claims (12)

Method for transporting and closing packages, in which the packages (18, 18 ') are advanced between at least one upper band (16) and at least one lower band (12) and then closed by fastening a closing part (20, 20') characterized in that the distance between the upper belt (16) and lower belt (12) is set by a swivel belt (14) protruding from the upper belt (16) in the direction of transport, for which purpose the upper belt (16) and the swivel belt (14) before the entry of a packaging (18, 18 ') are held in a lower basic position by spring force, and the swivel belt (14) with its lower end, viewed in the direction of transport, is initially placed obliquely upwards, whereupon when a package (18, 18') is advanced the swivel belt (14) is aligned horizontally up to a predetermined distance from the swivel belt (14), as a result of which the system (1, 18 ') comes to rest on one side e Swivel belt (14) is raised until the swivel belt (14) lies horizontally on the top of the packaging (18, 18 ') and the upper belt (16) is at the same time adjusted to the height of the packaging (18, 18'). Method according to claim 1, characterized in that the lower belt (12), the upper belt (16) and the swivel belt (14) are stopped as soon as an incoming packaging (18, 18 ') has reached a predetermined distance from the swivel belt (14), and that the lower band (12), the upper belt (16) and the swivel belt (14) for feeding the packaging (18, 18 ') are put back into operation as soon as the swivel belt (14) is aligned horizontally and thus the swivel belt (14) and the upper belt (16) the height of the packaging (18, 18 ') are set. Device for transporting and closing packaging, with at least one lower belt (12) and at least one upper belt (16) for advancing the packaging (18, 18 ') in the transport direction, characterized in that the upper belt (16) against a spring force parallel to the lower belt (12) is vertically movable that a swivel belt (14) is provided, which is rotatably connected with its rear end (13) as seen in the transport direction to the upper belt (16) and with its front end (15 as seen in the transport direction) ) can be adjusted obliquely upwards by means of a lifting cylinder (16), that the swivel belt (14) and the upper belt (16) are held in an approximately floating manner by at least one spring element (22, 24), with a small vertical force being applied downwards, and that the swivel belt (14) can be aligned horizontally via the lifting cylinder (16) by the distance between the swivel belt (18, 18 '), which initially lies obliquely on the packaging, and the upper belt (16) from the bottom band (12) to the height of the packaging (18, 18 '). Device according to claim 3, characterized in that the swivel belt (14) and the upper belt (16) form a continuous belt, the swivel belt (14) is designed as a pivotable belt part of the upper belt (16) protruding from the upper belt (16) in the opposite direction of transport. Apparatus according to claim 3 or 4, characterized in that the upper belt (16) is guided in a vertically displaceable manner via at least one vertical support (48, 50), and in that the swivel belt (14) at its front end (15) via the lifting cylinder (64) is held, which engages one of the vertical supports (48) at a fixed distance from the upper belt (16). Device according to one of Claims 3 to 5, characterized in that a control device (66) is provided which emits a switching signal to a switching valve (60) for the lifting cylinder (64) in order to move the swivel belt (14) before a packaging (18 , 18 ') which, when a predetermined distance between the incoming packaging (18, 18') and swivel belt (14) is reached, emits a switching signal to stop the upper belt (16), the swivel belt (14) and the lower belt (12) and to switch the switching valve (60) for the horizontal alignment of the swivel belt (14), and which emits a further switching signal to the upper belt (16), the swivel belt (14) and the lower belt (12) after the horizontal alignment of the swivel belt (14) in To put operation. Device according to one of claims 3 to 6, characterized in that the spring force of the spring elements (22, 24) is largely independent of the spring travel. Apparatus according to claim 7, characterized in that the spring elements (22, 24) are designed as gas pressure springs. Device according to one of claims 3 to 8, characterized in that the spring force of the spring elements (22, 24) is adjustable. Device according to one of claims 3 to 9, characterized in that the closing unit (30) is fastened to a holder (42) which can be moved in the vertical direction together with the upper belt (16). Apparatus according to claim 10, characterized in that a guide plate (62) extending in the feed direction of the lower belt (12) is provided for the vertical installation of a closing part (20, 20 ') which projects laterally from a package (18, 18'). Apparatus according to claim 10 or 11, characterized in that the closing unit (30) has a hold-down device (32) for holding down the top of the packaging, a lateral slide (28) for folding the closure part (20, 20 ') over the hold-down device (32) and one has vertically movable closers (26) for closing the packaging (18, 18 ') from above.

Images