EP2999632A1

EP2999632A1 - Device and method for folding open packaging sleeves

Info

Publication number: EP2999632A1
Application number: EP14711993.7A
Authority: EP
Inventors: Immo WEIDNER; Jürgen BLÜMEL; Thomas Vetten; Franco ZAGAR; Bernd VON BIRGELEN
Original assignee: SIG Technology AG
Current assignee: SIG Combibloc Services AG
Priority date: 2013-05-23
Filing date: 2014-03-25
Publication date: 2016-03-30
Also published as: BR112015029244A2; US20160107779A1; JP2016522124A; TW201446595A; DE102013105260A1; WO2014187592A1; ZA201508205B; AU2014270728A1; RU2015155246A; MX2015015631A; CN105246784A

Abstract

A device (12) for folding open packaging sleeves (10) is shown and described having: an apparatus (13) for providing the flat packaging sleeves (10), a transfer unit (14) which can be rotated about a rotational axis (27), and at least one suction element (24) for attracting the packaging sleeves (10) by suction, wherein the suction element (24) is at a spacing (26) from the rotational axis (27), and a transport belt (15) with at least one cell (31) which is intended to receive the packaging sleeves (10). In addition, a method for folding open packaging sleeves (10) is shown and described. In order to achieve a situation where reliable folding open and transferring of the packaging sleeves (10) to the conveyor belt is possible even in the case of a simple construction and in the case of a simple process sequence, it is proposed that the spacing (26) between the suction element (24) and the rotational axis (27) is constant, with the result that the packaging sleeves (10) are guided along a circular path (25).

Description

Apparatus and method for unfolding package coats

The invention relates to a device for unfolding packaging coats comprising: a device for providing the flat packing shells, a transfer unit which is rotatable about a rotation axis and has at least one suction element for sucking the packing shells, wherein the suction element is at a distance from the axis of rotation, and a Conveyor belt with at least one for receiving the

Packing coats particular cell.

The invention further relates to a method for unfolding of pack coats, comprising the following steps: providing the packaging coats by means of a device, sucking and continuing the packaging coats by means of a transfer unit rotating around a rotation axis with at least one suction element, and unfolding the packaging coats by inserting the packaging coats into one a cell attached to a conveyor belt.

In the field of packaging technology, numerous devices and methods are known, with which flat packing shells can be unfolded in order to subsequently fill them with contents. These are often expensive

Folding devices are required which pull apart the flat packing sheaths from both sides to bring them into the unfolded form.

Such a folding device is known from EP 0 112 605 A2. The flat packing shells are sucked in from both sides by suction elements.

Subsequently, the opposing suction elements from each other

led away, leaving the opposite sides of the packing jacket

be pulled apart and the packing jacket is unfolded. The solution described in EP 0 112 605 A2 has the disadvantage that the structure of the

Auffaltvorrichtung is very complex, since the packing jacket from both sides with Suction elements to be sucked, which can be moved towards and away from each other.

Another possibility for unfolding flat pack coats is known from WO 96/23655 A1. In this Auffaltvorrichtung the packing shells are inserted in the flat state in cells of a conveyor belt. On each cell a pivotable arm is attached to a suction member intended to fold the packing shells from the flat state to the tubular state. This unfolding device also has the disadvantage of a complex structure, since a pivotable arm with a suction element must be provided on each cell.

On separate Auffaltvorrichtungen can be dispensed with, however, if a relative speed, which arises for example in the transfer of packing coats from a first station to a second station of a filling plant, is exploited to unfold the packing coats. In other words, while it is still being fed from the first station of the plant, the package casing is already "hitting" a component of the second station of the plant which continues the package casing and is folded in this manner from US 3,060,654 The unfolding of the packaging shells is carried out by a rotating unit, which removes the flat packing sheaths from a magazine and transfers them to a conveyor belt This step is shown in particular in FIGS. 15a to 15f . The

Packing jackets are transferred from the rotating unit to the

Conveyor belt unfolded and clamped between two L-shaped brackets which are attached to the conveyor belt. One leg of the L-shaped bracket is on the

Conveyor belt attached, the other leg is from the conveyor belt and should hold the packing jacket sideways. At one end of the protruding leg a hook is provided which is intended to hold the packing jacket in position between the two brackets. The rotating unit has arms with suction cups, the perform a radial movement in the direction of the conveyor belt in addition to a rotational movement in order to transfer the packing shells to the conveyor belt. The insertion of the packing shells between the two L-shaped brackets is made possible by inserting the packing shells at a point where the conveyor belt is arcuate, so that the protruding legs of the L-shaped brackets are not parallel but spread apart. Only after the introduction of

Packungsmäntel is the conveyor belt in a straight course, wherein the spread of the protruding legs of the bracket goes back and the packing jacket between the now parallel extending projecting legs of the bracket is clamped.

The solution shown in US 3,060,654 initially has the disadvantage of a very complex construction. This is due to the fact that the arms of the rotating device should not only perform a rotary movement, but also to perform a movement in the radial direction to pull the packing coats from the magazine and to guide in the direction of the conveyor belt. Another disadvantage is the lack of variability of the structure. Since the packing shells are to be clamped in the manner described above between two L-shaped brackets, the insertion of the packing shells must be in the bracket at a point at which the conveyor belt passes from an arcuate course in a straight course. Inserting and fixing the packing shells in front of or behind this

Transition area is not provided in contrast.

The invention is therefore based on the object as well as the above-mentioned and previously described method to design and further develop the above-mentioned method such that, even with a simple construction and a simple procedure a reliable unfolding and transfer of the packaging coats on the task the conveyor belt is made possible. This object is achieved in a device according to the preamble of claim 1, characterized in that the distance between the suction element and the axis of rotation is constant, so that the packing shells are guided along a circular path, An aspect of the present invention is that the suction - and Thus, also sucked by the suction elements packing shells - are guided along a circular path. Through this geometrically simple leadership of

Suction elements and the packing shells, the transfer unit can be constructed particularly uncomplicated and inexpensive, for example, the transfer unit may have a cylindrical drum as the main component.

In particular, it is not necessary to mount the suction elements movable in the radial direction. This greatly facilitates the storage or attachment of the suction elements to the transfer unit. In addition, the supply of suction elements with negative pressure is facilitated by the fixed position of the suction.

Finally, the transfer unit of a device according to the invention is characterized by a particularly great robustness, as can be largely dispensed with movable components. The elimination of moving parts also has (food) hygienic advantages, since the lubrication of these parts is also eliminated. According to one embodiment of the invention, it is provided that the conveyor belt runs straight in the region of the device. By a straight course of the

Conveyor belts will be the insertion of the packing coats in the on the

Conveyor belt attached cells easier because the cells are during a longer distance in sufficient proximity to the transfer unit as in a curved course of the conveyor belt. In addition, no centrifugal forces occur in a straight course of the conveyor belt, which is especially at high

Operating speeds advantageous est. When the conveyor belt leaves the area of the device, however, a straight course of the conveyor belt is no longer required; In this area, the conveyor belt can also be deflected. Alternatively it can be provided that the conveyor belt is curved in the region of the device. In particular, the conveyor belt in the area of Device along a circular path. The arrangement of the device in a curved or circular portion of the conveyor belt has the advantage that even those areas in which the conveyor belt is deflected, can be exploited. This allows a particularly compact design of a system for folding, filling and sealing of Verpackungsmänteln.

A further embodiment of the invention provides that the device has at least one movably mounted finger with a projection for separating the flat packing shells. The height of the projection preferably corresponds to the height of a flatly folded packing sheath. The finger can be moved back and forth. This linear movement in the longitudinal direction can be superimposed by a movement in the transverse direction, so that the finger moves in total along an approximately oval trajectory. This construction ensures that the finger with the projection engages exactly one packing jacket and pushes it away from the stack during each cycle of movement The finger may have a well-defined stroke, so that the stacked packing jacket can be advanced into a desired position in order to be sucked by the suction elements can. By varying the stroke, the location at which the suction elements attack the packing shells can be changed. The stroke can, for example, in the range between 1 cm and 4 cm, in particular between 2 cm and

3 cm lie.

According to a further teaching of the invention, it is provided that the device has a shaft for guiding the packing shells whose center plane has an offset relative to the axis of rotation of the transfer unit. The length of the offset can be, for example, in the range between 1 cm and 6 cm, in particular between 2 cm and

4 cm are. The offset ensures that the suction elements the

Do not suck in the packaging coats in their middle, but in their edge area. In this way, the introduction of the packaging coats is facilitated in the cells, since the packing coats protrude particularly far from the suction elements when they are sucked in its edge region. In a further embodiment of the invention, it is provided that all suction elements are arranged at the same distance from the axis of rotation of the transfer unit. The

Transfer unit may have more than one suction element. If several

Suction elements are present on the transfer unit, it is advantageous all

To arrange suction elements in the same radial distance from the axis of rotation of the transfer unit to be able to safely suck the packing coats. The suction elements may be arranged in a row such that each packing jacket is sucked in by several suction elements at the same time. In addition, several rows of suction elements may be provided on the transfer unit. In this way, several packing shells can be sucked and unfolded with each revolution of the transfer unit. Preferably, the rows of suction elements are arranged distributed in identical intervals to one another uniformly over the circumference of the transfer unit.

According to a further embodiment of the invention, it is provided that the suction elements are inclined by an angle with respect to a tangential plane contacting the circular path. The angle may be, for example, in the range between 1 ° and 10 °, in particular between 3 ° and 6 °. The suction elements are preferably inclined in the direction of the direction of rotation of the transfer unit. The inclination has the advantage that the suction elements do not get caught on the packaging coats stored in the magazine. This danger is due to the fact that the circumferential edges of non-inclined suction elements lie in a tangential plane, so that seen in the direction of rotation foremost and rearmost point of a non-inclined Saugelements have a greater radial distance from the axis of rotation than that

Center of the suction elements, which lies exactly on the circular path, along which the suction elements are guided. Due to the inclination of the suction elements can thus be achieved in particular that the seen in the direction of rotation foremost point of the suction elements is again within the circular path, along which the

Suction elements are guided. In addition to reducing the risk of collision, the suction elements can better by the inclination on the packing shells be put on. Alternatively, or in addition to the inclination of Saugeiemente and the magazine, which contains the packaging coats, even by one

A further embodiment of the invention provides that the cells have two rigid side walls. In addition, a rigid rear wall may be provided. Under a rigid wall, a wall is understood that is rigid and in particular is not pivoting or folding. Rigid sidewalls offer a better

Stop point for the packaging coats as flexible or yielding side walls, whereby the unfolding of the packaging coats is facilitated. A rigid back wall provides a good attachment for the side walls.

With regard to these embodiments, it is further proposed that the side walls of the cells project perpendicularly from the rear wall and / or the conveyor belt. By the vertical course of the side walls, the unfolding of the packing shells is supported, as well as the packing shells in the unfolded state should have 90 ° angle.

Another teaching of the invention provides that the cells at least one

Have spring element for clamping the packing jacket in the cell. Due to the flexible spring element of the packing jacket is held securely in the cell. In order to be able to introduce a packing jacket into the cells, the spring element can be pushed back from the packing jacket or bent to the side. The spring element ensures, especially in the case of rigid cells, a secure hold of the packaging shells, since rigid cells themselves do not have a high clamping effect. For rigid cells without spring elements, the clamping effect must therefore be applied solely by the elasticity of the packing jacket, which has proved to be less reliable especially at high operating speeds than the use of spring elements. For this teaching is further proposed that the end of the spring element is hook-shaped. Due to the hook shape, the packing shells can be grasped particularly well behind and can be reliably held in the cell. According to a further embodiment of the invention, it is provided that the minimum distance between the circular path of the suction elements and the rear wall of the cell is smaller than the length of the side walls of the cells. By this arrangement it is achieved that the suction elements very close to the side walls of the cell

pass by and even "dive" into the cell in the area between the two side walls, which ensures a complete unfolding of the

Packungsmäntei, as the packing coats are pushed deep into the cells and only by the suction elements and the cell for unfolding

required forces are introduced into the packing jacket. The depth at which the suction elements "dive" into the cells can be in the range between 1 mm and 10 mm, depending on the format of the packaging material.

The above-described object is achieved in a method according to the preamble of claim 14, characterized in that the transfer unit leads the Packungsmäntei along a circular path with a constant distance between the suction element and the axis of rotation

As has already been described above in connection with the device according to the invention, the guidance of the packing case along a circular path has the advantage of a particularly simple procedure, in particular, no displacement of the packing element in the radial direction has to take place.

According to one embodiment of the method, it is proposed that the

Transfer unit rotates at an angular speed, which is always greater than zero. The transfer unit should therefore be stopped at any time, as would be the case with an intermittent operation. The angular velocity can

for example, fluctuate around an average value, whereby the course of the Angular velocity repeated in each packing jacket in the same way. A cyclic variation of the angular velocity allows optimization of the insertion of the packaging shells into the cells. The transfer unit can also rotate at a constant angular velocity. A constant

Angular velocity has the advantage of a particularly efficient

Process management. In particular, no extra energy is needed for that

Accelerating and decelerating the transfer unit can be used. In addition, a constant angular velocity has a positive effect on the service life of the machine, while operation with changing angular velocity or even intermittent operation usually shortens the service life.

A further embodiment of the method provides that the conveyor belt moves at a speed which is always greater than zero. As was previously done for the angular velocity of the transfer unit, should also

Conveyor belt are never stopped. A cyclic variation of the

However, speed, such as a mean variation, is possible. In order to ensure the synchronization between the transfer unit and the conveyor belt, the course of the speed must also be repeated here in the same way for each packing jacket. The conveyor belt can also move at a constant speed. Both the amount and the direction of the speed of the conveyor belt can be constant.

Preferably, the speed of the conveyor belt corresponds approximately to

Path speed with which the suction elements are guided along the circular path. In a cyclic variation of the angular velocity of

Transfer unit and the speed of the conveyor belt should this

Correspondence in any case for the average speeds and in particular for the speeds at the moment of delivery of the packing coats are met. In this way, a synchronous run between transfer unit and conveyor belt can be achieved and ensured that the of the

Suction elements sucked packing coats and their associated cells are brought together with exact timing. The unfolding of the packaging coats succeeds However, since the front edge of the packing jacket has a greater radial distance from the axis of rotation of the transfer unit than the suction elements and therefore also has a higher web speed than the suction elements and the cells.

In a further embodiment of the method is proposed that the

Packing coats are singled in the device by a movably mounted finger, which moves with a stroke in the range between 1 cm and 4 cm. The stroke in the direction of the packing shells corresponds to the distance by which the stacked packing sheath is advanced. By a variation of the stroke, the attack position of the suction elements can be changed to the packing coats.

After an embodiment of the method, it is proposed that the suction elements build up an underpressure in the angular range of 350 ° <φ <10 °; in particular, it can be provided that the suction elements build up a negative pressure in the angular range of approximately φ = 0 °. The angle of rotation φ begins in the region of the magazine at 0 ° and increases in the further course of the rotation of the transfer unit. The negative pressure can already be built up to 10 ° before reaching the magazine, in the range of the minimum distance between suction elements and conveyor belt is the Drehwinke! preferably about 180 °. Depending on the arrangement of magazine and

However, the conveyor belt can also have other values in the area of the conveyor belt of the rotation angle] and, for example, lie in the range between φ = 120 ° and φ = 270 °. The negative pressure should preferably be built up just before reaching the magazine by air is sucked.

A further embodiment of the method provides that the suction elements in the angular range of 125 ° <φ <145 ° again reduce the negative pressure. In particular, it can be provided that the suction elements in the angular range of about φ = 135 ° reduce the negative pressure again. The vacuum should be reduced to the

Let go of coat. This is done, for example, by terminating the Suction. The negative pressure should be released after the packing jacket has contact with the cell, but before the suction elements have reached their minimum distance to the conveyor belt. In an arrangement of the conveyor belt in the range of φ = 180 °, the negative pressure should therefore in the range between 125 ° (ie 55 ° before reaching the minimum distance to the conveyor belt) and 145 ° (ie 35 ° before reaching the minimum distance to the conveyor belt) degraded again become. With an arrangement of the conveyor belt, which deviates from the 180 ° position, results in a corresponding manner for the removal of the negative pressure

different rotation angle range.

Finally, it is proposed that the suction elements suck the packing shells at a distance away from their center, which lies in the range between 0 cm and 6 cm, in particular between 1 cm and 3 cm. The distance to the center can be in the range between 10% and 40% of the width of the packing shells. By the

Off-center suction of the packing shells is the leading edge of the

Packungsmantels significantly further from the suction element than the rear edge. This facilitates a sufficiently deep insertion of the packaging coats into the cells.

The invention will now be described with reference to a preferred one

Embodiment illustrative drawing explained in more detail. In the drawing show:

Fig. 1A is a known from the prior art blank for folding a

Pack casing,

FIG. 1B shows a packing jacket known from the prior art, which is formed from the blank shown in FIG. 1A, in the flat folded state, FIG. 1C shows the packing jacket from FIG. 1B in the unfolded state, FIG. Fig. 2 shows an inventive device for unfolding

Packungsmänteln in a plan view, and

Fig. 3 is a known from the prior art system for filling

Packs of food.

In Fig. 1A, a known from the prior art blank 1 is shown, from which a packing jacket can be formed. The blank 1 may comprise a plurality of layers of different materials, for example paper, cardboard, plastic or metal, in particular aluminum. The blank 1 has a plurality of fold lines 2, which are intended to facilitate the folding of the blank 1 and divide the blank 1 into several areas. The blank 1 may be subdivided into a first side surface 3, a second side surface 4, a front surface 5, a rear surface 6, a sealing surface 7, four bottom surfaces 8 and four surface surfaces 9. From the blank 1, a

Packing jacket are formed by the blank 1 is folded such that the sealing surface 7 connected to the front surface 5, in particular can be welded.

FIG. 1B shows a packing jacket 10 known from the prior art in the flat folded state. Those already described in connection with Fig. 1A

Features are provided in Fig. 1B with corresponding reference numerals. Of the

Packing jacket 10 is formed from the blank 1 shown in FIG. 1A. For this purpose, the blank 1 has been folded such that the sealing surface 7 and the front surface 5 are arranged overlapping, so that the two surfaces can be welded together flat. As a result, a longitudinal seam 11 is formed. In FIG. 1B, the packing jacket 10 is shown in a flat folded state. In this state, one side surface 4 (hidden in Fig. 1B) lies below the front surface 5 while the other side surface 3 lies on the rear surface 6 (obscured in Fig. 1B). In the flat folded state, several

Packungsmäntel 10 are stacked particularly space-saving. Therefore, the packing shells 10 are often stacked at the place of manufacture and stacked transported to the place of filling. Only there are the packing coats

stacked and unfolded to be filled with content, such as food. FIG. 1C shows the packing jacket 10 from FIG. 1B in the unfolded state. Again, the features already described in connection with FIG. 1A or FIG. 1B are provided with corresponding reference numerals. The unfolded state is understood to be a configuration in which an angle of approximately 90 ° forms between the two respectively adjacent surfaces 3, 4, 5, 6, so that the

Packing jacket 10 - depending on the shape of these surfaces - has a square or rectangular cross-section. Accordingly, the opposite side surfaces 3, 4 are arranged parallel to each other. The same applies to the front surface 5 and the rear surface 6. The packing shells 10 used can have different dimensions

The width of the side surfaces 3, 4 may be in the range between 30 mm and 80 mm The width of the front surface 5 and the rear surface 6 may be in the range between 40 mm and 120 mm Flat folded packing shells The widths of the side surfaces 3, 4 and the front and rear surfaces 5, 6 can therefore be in the range between 50 and 30 mm (30 mm + 40 mm) and 200 mm (80 mm + 120 mm) By way of example, for a filled and sealed package with a filling volume of 80 ml, outer dimensions of 47 mm × 32.5 mm × 55 mm are obtained, and for a package with a filling volume of 2000 ml, this results in external dimensions of 114 mm × 74 mm × 245 mm.

Fig. 2 shows an inventive device 12 for unfolding

Packungsmänteln 10 in a plan view. The device 12 comprises a device 13 for providing, in particular for separating flat packing sheaths 10, a transfer unit 14 and a conveyor belt 15. The device 13, which is also referred to as a "magazine", has a housing 16 with a shaft 17, into which a stack of flat packing shells 10 can be placed in. The shaft 17 has a center plane 18, which is centered through the shaft 17 2, the center plane 18 can be oriented perpendicular to the conveyor belt 15. Alternatively, the center plane 18 can also be inclined with respect to this vertical line 13. The device 13 also has a plurality of fingers 19 arranged one behind the other in a row. each having a projection 20. The height of the projection 20 corresponds approximately to the height of a flat folded packaging jacket 10. To unstack the packing 10 coats perform the catcher 19 a cyclical movement, the hub 21 is indicated in Fig. 2 with an arrow through the Reciprocating the fingers 19 is achieved that the fingers 19 with its projection 20 pro

Movement cycle each push out a packing jacket 10 through an opening 22 of the device 13 to be taken over there by the transfer unit 14 can. The remaining packing shells 10 are continuously pushed by a force F directed in the direction of the fingers 19, so that a continuous stacking and separation of the packing shells 10 is ensured

The transfer unit 14 comprises a drum 23 to which a plurality of suction elements 24 are attached. The illustrated in Fig. 2 and so far preferred drum 23 has a cylindrical shape and thus a circular cross-sectional area. The four rows of suction elements 24 are arranged on a circular path 25 at a constant distance 26 or radius, wherein the circular path 25 through the center of the

Suction elements 24 extends The suction elements 24 are fixed in position, so that all suction elements 24 always have the same, unchangeable distance to a rotation axis 27 around which the drum 23 rotates at an angular velocity co and by a rotation angle φ. The device 13 and the transfer unit 14 are arranged such that between the rotation axis 27 of the transfer unit 14 and the

Through the stroke 21 of the fingers 19 and by the offset 28 ensures that the suction elements 24, the packaging coats 10 not in its center, but in its edge region suck. The suction elements 24 can be acted upon by (not shown in FIG. 2) lines with a negative pressure to the packing shells 10 in the region of

Suction device 13 (approximately at a rotation angle of φ = 0 °) and to pass in the further course of the rotation of the drum 23 to the conveyor belt 15 (approximately at a rotation angle of φ = 180 °). The suction elements 24 are preferably slightly inclined, so that the edges of the suction elements 24 lie in a plane 29 which is inclined α relative to a tangential plane 30 of the circular path 25 at an angle α in this way, the suction elements 24 are slightly in the direction of rotation of the drum 23rd inclined and can suck the packing coats 10 better.

The conveyor belt 15 runs straight in the section shown in FIG. 2 and has a speed v. In the conveyor belt 15 may be

For example, to act on a belt or a chain. On the conveyor belt 15 a plurality of cells 31 are attached, which serve to receive the packing shells 10. The cells 31 comprise a rear wall 32 and two side walls 33. The rear wall 32 runs parallel to the conveyor belt 15 and is connected thereto. The two side walls 33 are perpendicular from the rear wall 32; they are therefore arranged parallel to each other. The rear wall 32 and the two side walls 33 are made of metal and have no joints or the like, so that it is a rigid cell 31 so far. The cells 31 have two spring elements 34, wherein preferably on each side wall 33, a spring element 34 is arranged. The spring elements 34 are made of an elastic material, for example a

Spring steel or a flexible plastic made and have a protruding end 35 which is hook-shaped. Due to the hook shape, the

Spring elements 34 hold the packing shells 10 in the cells 31 and

Clamp.

The cells 31 are arranged at a constant distance 36 from one another, which is also referred to as a "stitch." This distance 36 corresponds approximately to the length of one

Arc segment, which along the circular path 25 between two adjacent Suction elements 24 extends; in four suction elements 24, the distance 36 thus corresponds to about a quarter of the circumference of the circular path 25. The transfer unit 14 is arranged opposite the conveyor belt 15 such that between the circular path 25 of the suction elements 24 and the rear wall 32 of the cells 31, a minimum distance 37 is formed is slightly smaller than the length of the side walls 33 of the cells 31 so that the suction elements 24 "dive" into the cells at a depth 37 'in the area between the two side walls 33. A collision can be prevented by placing in the side walls 33 of the cells 31 and in the spring elements 34

Recesses are provided, through which the suction elements 24 can be performed.

The unfolding of the packing shells 10 takes place by the following steps: First, a packing sheath 10 is pushed out of the feeding device 13 through the projection 20 of the finger 19 through the opening 22. There will be the

Packing jacket 10 sucked by a suction element 24 of the transfer unit 14 and continued along the circular path 25. After about one-third revolution of the drum 23 (rotation angle of φ = 120 °), the packing jacket 10 approaches the conveyor belt 15 and its associated cell 31. The transfer unit 14 and the conveyor belt 15 are arranged relative to each other such that an in

Seen in the direction of rotation, the leading edge 38 of the packing jacket 10 first abuts the cell 31. Strictly speaking, a corner between the rear wall 32 and one of the side walls 33 of the cell 31 serves as a stop for the edge 38. As soon as the edge 38 of the packing jacket 10 touches the cell 31, forces in the packing jacket are only at two locations apart from centrifugal forces 10 introduced: first, in the region of the suction element 24, which leads the packing jacket 10, and secondly on the front edge 38 of the packing jacket 10. These two locations have a distance 39 to each other. By a certain arrangement of the transfer unit 14 relative to the conveyor belt 15 and by certain movement speeds and directions of movement of transfer unit 14 and conveyor belt 15 is achieved that the distance 39 during insertion of the package shell 10 in the cell 31 is continuously reduced. In this way, two become each other directed forces 40, 41 introduced into the packing jacket 10, which cause the packing jacket 10 is unfolded. The unfolding of the packaging shells 10 thus takes place exclusively by the action of the suction elements 24 and the cell 31 on the packing jacket 10; however, separate unfolding devices are not required.

For the described type of unfolding is a precise and sufficiently deep

Introduction of the packing shells 10 in the cells 31 required. This succeeds despite the simple rotational movement of the drum 23, mainly due to the fact that the suction elements 24, the packing shells 10 not in the middle, but in one

Vacuum 42 away from its center. This distance 42 corresponds approximately to the sum of the stroke 21 and the offset 28 and may for example be in the range between 0 cm and 6 cm and in particular between 1 cm and 3 cm, in relation to the width of the packing shells 10, the distance 42 to the center in Range between 10% and 40% of the width of the packaging 10 coats.

FIG. 3 shows a system 43 known from the prior art for filling food packs (EP 0 112 605 A2). The individual stations of the system 43 are shown only schematically in FIG. 3, since FIG. 3 is merely intended to serve as a possible field of application of a device 12 according to the invention for the purpose of FIG

Unfolding of Packungsmänteln 10 to illustrate. The packing shells 10 (not shown in FIG. 3) are unfolded by a station 44 and transferred to the cells 31 of the conveyor belt 15. The station 44 can be replaced by the device 12 according to the invention. The system 43 comprises a first rotary 45 in which the gable surfaces 9 of the packing shells 10 are prefolded. The packing shells 10 then pass through a station 46, in which the bottom surfaces 8 of the packing shells 10 are prefolded. After the prefolding, the

Bottom surfaces 8 of the pack coats 10 folded in a station 47 and sealed. Subsequently, the conveyor belt 15 is guided around a second rotary 48, in which the sealed on the underside of the packaging coats

Be filled with food. In a further station 49, the gable surfaces 9 the packing shells 10 folded and sealed Finally, the now filled and sealed packing shells 10 are removed in a further station 50 from the cells 31 of the conveyor belt 15 and discharged from the system 43 again.

LIST OF REFERENCE NUMBERS

1: cut

2: fold line

3, 4: side surfaces

5: front surface

6: rear surface

7: sealing area

8: floor area

9: gable area

10: packing jacket

11: longitudinal seam

12: Device for unfolding packaging coats

13: device for providing packaging coats 14: transfer unit

15: conveyor belt

16: housing

17: shaft

18: middle plane

19: fingers

20: lead

21: stroke

22: opening

23: drum

24: suction element

25: circular path

26: distance

27: rotation axis

28: offset

29: level

30: tangent plane 31: cell

32: rear wall

33: side wall

34: spring element

35: End of the spring element

36: distance of the cells

37: Minimum distance

37 ': depth

38: edge of the packing jacket

39: distance

40, 41: Forces

42: distance

43: Plant

44: station (unfolding)

45: Rotary (prefolding gable surfaces)

46: station (prefolding floor areas)

47: station (bottom seal)

48: rotary (filling)

49: station (gable sealing)

50: station (discharge)

F: force

ω: angular velocity of the transfer unit φ: rotation angle of the transfer unit

v: Speed of the conveyor belt α: inclination angle

Claims

Patent claims

1. Device (12) for unfolding packaging jackets (10) with:

- a device (13) for providing the flat packaging jackets (10),

- a transfer unit (14) which is rotatable about an axis of rotation (27) and has at least one suction element (24) for sucking in the packaging casings (10), the suction element (24) being at a distance (26) from the axis of rotation (27). , and

- A conveyor belt (15) with at least one for receiving the

Packing jackets (10) determine cell (31),

characterized in that

the distance (26) between the suction element (24) and the axis of rotation (27) is constant, so that the packing jackets (10) are guided along a circular path (25),

2. Device according to claim 1,

characterized in that

the conveyor belt (15) runs straight in the area of the device (12).

3. Device according to claim 1,

characterized in that

the conveyor belt (15) is curved in the area of the device (12).

4. Device according to one of claims 1 to 3,

characterized in that

the device (13) has at least one movably mounted finger (19) with a projection (20) for separating the flat packaging jackets (10).

5. Device according to one of claims 1 to 4,

characterized in that

the device (13) has a shaft (17) for guiding the packaging jackets (10), the central plane (18) of which is opposite the axis of rotation (27).

Transfer unit (14) has an offset (28).

6. Device according to one of claims 1 to 5,

characterized in that

all suction elements (24) are arranged at the same distance (26) from the axis of rotation (27) of the transfer unit (14).

7. Device according to one of claims 1 to 6,

characterized in that

the suction elements (24) are inclined at an angle (α) relative to a tangential plane (30) touching the circular path (25).

8. Device according to one of claims 1 to 7,

characterized in that

the cells (31) have two rigid side walls (33).

9. Device according to one of claims 1 to 8,

characterized in that

the cells (31) have a rigid rear wall (32).

Device according to claim 8 or claim 9,

characterized in that

the side walls (33) of the rows (31) protrude vertically from the rear wall (32) and/or the conveyor belt (15).

11. Device according to one of claims 1 to 10,

characterized in that the cells (31) have at least one spring element (34) for clamping the

Have packing jacket (10) in the cell (31).

12. Device according to claim 11,

characterized in that

the end (35) of the spring element (34) is hook-shaped.

13. Device according to one of claims 1 to 12,

characterized in that

the minimum distance (37) between the circular path (25) of the suction elements (24) and the rear wall (32) of the cell (31) is smaller than the length of the side walls (33) of the cells (31).

14. Method for unfolding packaging jackets (10) comprising the following steps:

a) providing the packaging casing (10) by a device (13), b) sucking in and forwarding the packaging casing (10) by a transfer unit (14) rotating about an axis of rotation (27) with at least one suction element (24), and

c) unfolding the packaging casing (10) by inserting the packaging casing (10) into a cell (31) attached to a conveyor belt (15),

characterized in that

the transfer unit (14) guides the pack casing (10) along a circular path (25) with a constant distance (26) between the suction element (24) and the axis of rotation (27).

15. Method according to claim 14,

characterized in that

the transfer unit (14) rotates at an angular velocity (ω) that is always greater than zero.

16. Method according to claim 14 or claim 15,

characterized in that

the transfer unit (14) rotates at a constant angular velocity (ω).

17. Method according to one of claims 14 to 16,

characterized in that

the conveyor belt (15) moves at a speed (v) that is always greater than zero

18. Method according to one of claims 14 to 17,

characterized in that

the conveyor belt (15) moves at a constant speed (v).

19. Method according to one of claims 14 to 18,

characterized in that

the packing jackets (10) are separated in the device (13) by a movably mounted finger (19), which moves with a stroke (21) in the range between 1 cm and 4 cm

20. Method according to one of claims 14 to 19,

characterized in that

the suction elements (24) build up a negative pressure in the angular range of 350° < φ < 10°.

21. Method according to one of claims 14 to 20,

characterized in that

the suction elements (24) reduce the negative pressure again in the angular range of 125° < φ < 145°.

22. Method according to one of claims 14 to 21,

characterized in that

the suction elements (24) suck the packing jackets (10) at a distance (42) from their center, which is in the range between 0 cm and 6 cm, in particular between 1 cm and 3 cm.