DEVICE AND METHOD FOR CUTTING OFF AND PROVIDING A FILM PART UNIT FROM A FOOD PACKAGING FILM STRIP

Abstract

The present invention proposes a device (1) that saves time and costs and is reliable and gentle on material for cutting off and providing a film part unit (20) from a food-packaging film strip (7), comprising a cutting station (2) which is adapted to intermittently cut off film part units (20) from a food-packaging film strip (7) which intermittently passes through the cutting station (2) in a conveying direction (5), characterized in that the cutting station (2) is adapted to pre-cut a film part unit (20) in one working step, where the film part unit (20) remains connected to the film strip (7), and to cut off from the film strip (7) a film part unit (20) that adjoins in the conveying direction (5) and has already been pre-cut in a preceding working step. The invention also relates to a corresponding method.

Claims

1. Device (1) for cutting off and providing a film part unit (20a, 20c) from a food-packaging film strip (7), comprising a cutting station (2) which is adapted to intermittently cut off film part units (20a, 20c) from a film strip (7) which intermittently passes through said cutting station (2) in a conveying direction (5), characterized in that said cutting station (2) is adapted to pre-cut a film part unit (20a) in one working step, where said film part unit (20a) remains connected to said film strip (7), and to cut off from said film strip (7) a film part unit (20b) that adjoins in the conveying direction (5) and has already been pre-cut in a preceding working step.

2. Device (1) according to claim 1, characterized in that said cutting station (2) comprises a knife assembly (11) defining said film part unit (20a, 20b, 20c), where a severing knife (31) in said conveying direction (5) arranged last provides a cut transverse to said conveying direction (5) which separates said film part unit (20b) from said film strip (7).

3. Device (1) according to claim 2, characterized in that said knife assembly (11) comprises at least one pre-cutting knife (32), in particular several pre-cutting knives (32) spaced apart, extending from said severing knife (31) against said conveying direction (5) and/or at an angle to said conveying direction (5).

4. Device (1) according to claim 2 or 3, characterized in that said knife assembly (11) comprises a further severing knife (33) which is arranged in said conveying direction (5) upstream of said severing knife (31) and provides a cut transverse to said conveying direction which completely cuts off at least one film part (29) of said film part unit (20a) from said film strip (7).

5. Device (1) according to claim 4, characterized in that at least one further pre-cutting knife (35), in particular several further pre-cutting knives (35) spaced apart, extend from said further severing knife (33) at an angle to and/or against said conveying direction (5).

6. Device (1) according to one of the claims 2 to 5, characterized in that, said cutting station (2) comprises a movable punch knife (10) with said knife assembly (11).

7. Device (1) according to one of the preceding claims, characterized in that said device (1) comprises a movable transfer unit (3) which is adapted to selectively couple to a pre-cut film part unit (20b) located in said cutting station (2) and move it in said conveying direction (5), in particular, to move it out of said cutting station (2).

8. Device (1) according to claim 7 and to the extent depending on claim 2, characterized in that said transfer unit (3) is adapted to move a film part unit (20b) located in said cutting station (2) with its connection point (30) to said film strip (7) to that location where said severing knife (31) provides a cut transverse to said conveying direction (5).

9. Device (1) according to claim 7 or 8, characterized in that said transfer unit (3) is adapted to couple and/or decouple said film part unit (20b, 20c) only on one side of the film.

10. Device (1) according to one of the claims 7 to 9, characterized in that, said transfer unit (3) comprises a suction device, in particular a suction plate (18).

11. Device (1) according to one of the preceding claims, characterized in that said device (1) comprises a film conveyor unit (4) which can selectively couple and hold a partial section of said film strip (7) in said conveying direction (5) located upstream of said cutting station (2) and/or move it in said conveying direction (5).

12. Device (1) according to claim 11, characterized in that said film conveyor unit (4) and said transfer unit (3) are connected to one another by way of a movable rigid structure, in particular by way of a carriage (6).

13. Device (1) according to one of the claims 11 to 12, characterized in that, said film conveyor unit (4) comprises a clamping device (24, 25) which can selectively clamp said partial section of said film strip (7) on both sides of said film strip (7).

14. Device for cutting off and providing a film part unit (20a, 20c) from a food-packaging film strip (7), where film part units (20a, 20c) are intermittently cut off from a film strip (7) which runs intermittently in a conveying direction (5), characterized in that said film part unit (20a) is pre-cut in one working step, where it remains connected to said film strip (7), and a film part unit (20b) adjoining in said conveying direction (5) and already pre-cut in a preceding working step is cut off in the same working step from said film strip (7).

15. Method according to claim 14, characterized in that said film part unit (20a) is pre-cut into at least one film part (28) that is connected to said film strip (7) and at least one film part (29) that is completely cut off from said film strip (7).

16. Method according to claim 14 or 15, characterized in that said film part unit (20a) is pre-cut with a knife assembly (11) and said adjacent film part unit (20b) is also cut off with said knife assembly (11), in particular with a punch knife (10) which is comprised by said knife assembly (11).

17. Method according to one of the claims 14 to 16, characterized in that said pre-cut film part unit (20b) is moved with its connection point (30) to said film strip (7) to a position in said conveying direction (5) at which it is cut off from said film strip (7) during a pre-cutting step of a trailing film part unit (20a).

18. Method according to one of the claims 14 to 17, characterized in that said pre-cut film part unit (20b) is selectively coupled by a transfer unit (3), in particular by a movable suction device, especially by a movable suction plate (18), and moved in said conveying direction (5).

19. Method according to one of the claims 14 to 18, characterized in that said film part unit (20c) cut off from said film strip (7) is moved to a downstream processing station (16).

20. Method according to one of the claims 14 to 19, characterized in that a partial section of said film strip (7), which in said conveying direction (5) is upstream of said pre-cut film part unit (20b), is moved simultaneously with said pre-cut film part unit (20b) in said conveying direction (5), in particular at a uniform distance from said pre-cut film part unit (20b).

Description

[0027] For better understanding of the invention, a possible embodiment of the invention shall be explained in more detail with reference to the figures described below, where

[0028] FIG. 1 shows a schematic lateral view of a device according to the invention in a state in which a film part unit is located already pre-cut in a cutting station;

[0029] FIG. 2 shows the schematic view of FIG. 1 in a state in which a transfer unit has moved into the cutting station and couples the pre-cut film part unit;

[0030] FIG. 3 shows the schematic view of FIG. 2 in a state in which the transfer unit has moved the pre-cut film part unit, still connected to the film strip, out of the cutting station to a defined position;

[0031] FIG. 4 shows the schematic view of FIG. 3 in a state in which the cutting station has cut off the already pre-cut film part unit from the film strip and has pre-cut a subsequent film part unit in the same working step;

[0032] FIG. 5 shows the schematic view of FIG. 4 in a state in which the transfer unit has conveyed the cut-off film part unit to a downstream processing station;

[0033] FIG. 6 shows a schematic top view of a film part unit, not yet pre-cut, with film parts still connected;

[0034] FIG. 7 shows a schematic top view of a pre-cut film part unit with partially separated film parts;

[0035] FIG. 8 shows a schematic top view of a film part unit that is entirely cut off from the film strip with the film parts separated;

[0036] FIG. 9 shows a schematic top view of the cutting side of a punch knife;

[0037] FIG. 10 shows a schematic view from above of the device shown in FIG. 3.

[0038] The configuration of the device according to the invention shall first be described with reference to FIGS. 1 and 6 to 10.

[0039] As can be seen in FIG. 1, device 1 comprises a cutting station 2, a transfer unit 3 and a film conveyor unit 4.

[0040] Transfer unit 3 and film conveyor unit 4 are positioned on a carriage 6 which moves to and fro along conveying direction 5 and pull a film strip 7 intermittently in conveying direction 5 through cutting station 2. Film strip 7 extends in the region of cutting station 2 in a taut and wrinkle-free manner, approximately along conveying direction 5.

[0041] Conveying direction 5 of film 7 is drawn as a dashed arrow in all figures.

[0042] Cutting station 2 comprises a punch 8 that moves to and fro linearly and perpendicularly to conveying direction 5 between an open retracted position and a closed cutting position and that comprises a punch knife 10 with a knife assembly 11 on a side 9 facing film strip 7. Punch 8 is driven by a linear actuator 12. Cutting station 2 further comprises a punching table 13 which is arranged opposite punch 8, so that film strip 7 runs between punch 8 and punching table 13. During operation, film strip 7 is pulled intermittently by transfer unit 3 over punching table 13.

[0043] Located in the conveying direction 5 upstream of cutting station 2 is a film supply unit 14 which rotatably supports film strip 7 in the form of a peelable film coil 15. Film coil 15 can be rotatably driven and/or braked to assist the peeling operation.

[0044] Disposed in conveying direction 5 downstream of cutting station 2 is a processing station 16 which comprises hollow molds 17 for molding packaging halves for hollow figurines.

[0045] Transfer unit 3 comprises a suction plate 18. Suction plate 18 is planar on its underside 19 facing film strip 7 and on its upper side 22 and in the open position of punch 8 can retract into pre-cutting unit 2 in order to there suction a pre-cut film part unit 20b by way of negative pressure, pull it out in conveying direction 5 from cutting station 2 and finally deposit it in processing station 16.

[0046] FIG. 10 shows suction plate 18 with a suctioned pre-cut film part unit 20b outside of cutting station 2. Suction plate 18 is provided with through holes 21 at locations at which during positioning in cutting station 2 on the underside 19 thereof individual film parts 28, 29 (hereinafter referred to as parts) of pre-cut film part unit 20b are located, so that the application of negative pressure from upper side 22 of suction plate 18 causes a negative pressure at underside 19 of suction plate 18. Parts 28, 29 of film part unit 20b can therefore be selectively coupled by planar underside 19 along the entire surface of their upper side.

[0047] Located on upper side 22 of suction plate 18 are negative pressure lines 23 which are connected to through holes 21. For the sake of clarity, negative pressure lines 23 are shown schematically only in FIG. 10, where only some of them are provided with reference numerals. They are controllably connected to a negative pressure reservoir which is not shown for reasons of clarity. For ease of understanding, pre-cut film part unit 20b suctioned onto underside 19 in FIG. 10 is shown with its parts 28, 29 in dashed lines. The same applies to a film part unit 20astill uncutbelow punch 8.

[0048] As can be seen in FIG. 10, suction plate 18 is attached to one end of movable carriage 6. Compared to film strip 7, suction plate 18 is disposed in the vertical direction on the side of punch 8 and spans film strip 7 like a bridge transverse to conveying direction 5. Transfer unit 3 can therefore move to and fro in a region above film strip 7 and between cutting station 2 and processing station 16.

[0049] As can be seen from FIG. 10 in conjunction with FIG. 1, film conveyor unit 4 there has four clamping jaws 24, 25, where two clamping jaws 24, 25 are disposed opposite each other on either side of film strip 7. Clamping jaws 24 respectively located on one film side are connected to each other via a cross member 26 of carriage 6 which stretches across the entire width of film strip 7 transverse to conveying direction 5. Clamping jaws 24, 25 are controllably movable between a state that is closed, thereby clamping film strip 7, and a state that is open, thereby releasing film strip 7.

[0050] Transfer unit 3 and film conveyor unit 4 are connected rigidly and at a defined distance from each other by way of two longitudinal members 27 of carriage 6 which extend parallel to each other and parallel to conveying direction 5. The respective ends of longitudinal members 27 are connected to each other by two cross members 26 as well as suction plate 18. Suction plate 18 is disposed movable in the vertical direction, i.e. perpendicular to conveying direction 5, in a manner controllable by actuators, not shown, on longitudinal members 27. Carriage 6 is driven by a controllable movement unit, not shown, and moved to and fro in conveying direction 5.

[0051] FIG. 6 shows a film part unit 20a in a state where it is still uncut. The points where punch knife 10 provides cuts are shown in dashed lines. The total of presently 6 rectangular parts 28, 29 of film part unit 20a are arranged in the array 3 x 2 and share one end of film strip 7 completely among each other. The number of parts 28, 29 and their arrangement in conveying direction 5 and transverse to conveying direction 5 can be varied at random, as necessary, by way of the configuration of knife assembly 11, as shall be explained further on.

[0052] FIG. 7 shows a film part unit 20b in the pre-cut state. Pre-cut film part unit 20b comprises six parts 28, 29, where three parts 29 are already completely cut off from remaining film strip 7 and from each other, and three further parts 28 are respectively still connected to film strip 7 at a side edge 30. Side edges 30 represent the connection point of pre-cut film part unit 20b to remaining film strip 7. Parts 29 completely cut off from film strip 7 are arranged in one row next to one another across the entire width of film strip 7 at the point of film strip 7 which in conveying direction 5 is the outermost one.

[0053] FIG. 8 shows a film part unit 20c in its fully cut off state. All six parts 28, 29 are completely cut off from adjoining parts and from remaining film strip 7.

[0054] FIG. 9 shows punch knife 10 of punch 8 with knife assembly 11.

[0055] Knife assembly 11 comprises a severing knife 31 which in conveying direction 5 is arranged last and provides a cut that is transverse to conveying direction 5 and that separates pre-cut film part unit 20b at connection point 30 of film strip 7 when moved out of the cutting station. Severing knife 31 is there an elongate blade which extends perpendicular to conveying direction 5 and plumb-vertical to the film strip end located in cutting station 2.

[0056] Knife assembly 11 further comprises two spaced blade-like pre-cutting knives 32 which extend from severing knife 31 against conveying direction 5 and in parallel thereto.

[0057] Knife assembly 11 also comprises a further blade-like severing knife 33 which is arranged in conveying direction 5 upstream of severing knife 31 and also provides a cut transverse to conveying direction 5 across the entire width of film strip 7. Further severing knife 33 extends parallel to severing knife 31 and perpendicular to pre-cutting knives 32. The cut provided by this further severing knife 33 completely separates parts 29 shown in FIG. 6 from film strip 7 at dashed line 34.

[0058] Knife assembly 11 comprises two further blade-like pre-cutting knives 35 which extend parallel to and against conveying direction 5 from further severing knife 33 and there continue pre-cutting knives 32. The common length of pre-cutting knives 32, 35 corresponds to the length of cuts 36 in FIG. 7 in conveying direction 5 running parallel to the conveying direction.

[0059] When comparing knife assembly 11 shown in FIG. 9 with film part unit 20a shown in dashed lines in FIG. 6, it becomes clear that knife assembly 11 defines the format of film part unit 20a. Film part unit 20a is separated by knife assembly 11 into individual parts 28, 29, where all parts 28, 29 can be used in the downstream treatment processes.

[0060] The mode of operation of device 1 according to the invention and the method according to the invention shall be explained in more detail with reference to FIGS. 1 to 5. FIGS. 1 to 5 schematically show device 1 in temporally successive working steps. Motions of individual members, which are performed in a directly subsequent working step, are indicated by arrows for better understanding.

[0061] Clamping jaws 24, 25 are open in the state shown in FIG. 1. Located on punching table 13 is a pre-cut film part unit 20b in a state as shown in FIG. 7.

[0062] Suction plate 18 is located in conveying direction 5 at the level of hollow molds 17. Individual parts 28, 29 of a cut off film part unit 20c were just placed on hollow molds 17 of processing station 16 due to the interruption of the negative pressure at suction plate 18 and suction plate 18 has already traveled some distance vertically upwardly away from hollow molds 17. Carriage 6 with suction plate 18 and clamping jaws 24, 25 is in conveying direction 5 in its maximum position. Punch 8 is in its retracted position.

[0063] Carriage 6 subsequently drives suction plate 18 and film conveyor unit 4 against conveying direction 5 until suction plate 18 enters cutting station 2 in the corridor formed between punch 8 and punching table 13 and is stopped above pre-cut film part unit 20b. Carriage 6 with suction plate 18 and clamping jaws 24, 25 is against conveying direction 5 in its maximum position. Punch 8 continues to be in its retracted position.

[0064] Suction plate 18 now moves vertically onto pre-cut film part unit 20b until underside 19 is in planar contact with film part unit 20b. Film part unit 20b is now suctioned by negative pressure and thereby coupled on one side to suction plate 18 in a planar manner. Both parts 28 that are still connected to film strip 7 as well as parts 29 that are already cut off from film strip 7 are coupled by suction plate 18.

[0065] Shortly after suction plate 18 has coupled to film part unit 20b, oppositely disposed clamping jaws 24, 25 also move toward each other and clamp a partial section of film strip 7 that is in conveying direction 5 upstream of cutting station 2. This state is shown in FIG. 2.

[0066] Carriage 6 subsequently moves suction plate 18 with suctioned and pre-cut film part unit 20b in conveying direction 5 to a defined position, so that connection point 30 is aligned with severing knife 31 and can be cut off by the latter in a punching operation. In the motion of the carriage, the pulling motion of suction plate 18 is transferred to the remaining film strip 7 due to connection point 30 still existing between pre-cut film part unit 20b and remaining film strip 7, and remaining film strip 7 is thereby also pulled in conveying direction 5 and a portion thereof is conveyed into cutting station 2 and comes to rest as a pre-cut film part unit 20a below punch knife 10 on punching table 13.

[0067] Film conveyor unit 4 with closed clamping jaws 24, 25 there supports film strip 7 in its motion in conveying direction 5 and thus limits the tensile force acting on connecting point 30. Pre-cut film part unit 20b unintentionally tearing off at connection point 30 during the pull is thus prevented in the case of a long and heavy film web 7 and/or a film coil 15 which is hard to unroll.

[0068] Parts 28, 29 deposited in processing station 16 in the meantime have been formed with a forming die, not shown, to hollow half shells, and are then transported via a gripper, also not shown, to a subsequent working step.

[0069] FIG. 3 shows pre-cut film part unit 20b with suction plate 18 and connection point 30 in the position described above.

[0070] Located beneath punch 8 is now a film part unit 20a that is still uncut, as shown in FIG. 6.

[0071] Punch 8 now moves with knife assembly 11 toward punching table 13, thereby transferring its knife assembly 11 in the form of cuts onto film strip 7. Closed clamping jaws 24, 25 avoid that the motion of punch knife 10 is adversely transferred to portions of film strip 7 that are in conveying direction 5 located upstream of clamping jaws 24, 25.

[0072] FIG. 4 shows punch 8 in its fully extended position in which punch knife 10 has penetrated film strip 7 at locations determined by knife assembly 11. In a subsequent working step, punch 8 moves back to its retracted position and clamping jaws 24, 25 open.

[0073] Film part unit 20b on punching table 13 is now pre-cut, as shown in FIG. 7. Pre-cutting within the meaning of the invention is understood to be any kind of separation, including only the partial separation of film/film portions. Film part unit 20c, which is coupled to suction plate 18, is now completely separated from film strip 7 and is present in the form shown in FIG. 8, in which all parts 28, 29 are completely separated. Pre-cutting a film part unit 20a that is not yet pre-cut and cutting off an adjoining already pre-cut film part unit 20b is therefore carried out in one cutting operation. These cutting operations preferably occur simultaneously.

[0074] Clamping jaws 24, 25 subsequently open.

[0075] Carriage 6, with open clamping jaws 24, 25 and parts 28, 29 coupled to suction plate 18, now moves in conveying direction 5 until suction plate 18 is located above hollow molds 17.

[0076] FIG. 5 shows how suction plate 18, there still coupled to film part unit 20c that is entirely cut off, is located above hollow molds 17 in processing station 16.

[0077] In a subsequent working step, suction plate 18 is moved with film part unit 20c toward hollow molds 17 and the negative pressure applied to suction plate 18 is terminated. As a result, film part unit 20c, with its individual parts 28, 29 completely separated from each other, is placed accordingly onto hollow molds 17.

[0078] The subsequent working step is similar to the working step previously described for FIG. 1.

[0079] According to further possible embodiments, the food-packaging film cut off and provided according to the present invention can be a metal film, in particular an aluminum film, a plastic film or a film as an aluminum-plastic composite.

[0080] In further possible embodiments, the food-packaging film cut off and provided according to the invention can be a film for packaging chocolate, preferably a film for packaging hollow chocolate figurines.

[0081] According to further possible embodiments, the food-packaging film cut off and provided according to the invention can have a film thickness in the range from 5 m to 100 m, in particular a thickness in the range from 10 m to 50 m, especially a thickness in the range from 15 m to 30 m.