Packaging machine with suction plate

Abstract

A packaging machine comprising a machine frame, at least one work station attached to the machine frame, and a transport device with a transfer unit for feeding trays to the work station, wherein the transfer unit comprises a suction plate for transporting trays in a predetermined transport plane. The suction plate may comprises at least one reception mold which is formed at least in part having the shape of an inner contour of an upper opening region of a tray facing it, provided to the reception mold for reception and transport, so that the reception mold during transport in the transport plane of the tray is arranged in a positive-fit manner in its upper opening region and aligns the tray in the transport plane in a predetermined position on the suction plate. The invention also relates to a method for supplying trays to a work station of a packaging machine.

Claims

1. A packaging machine comprising: a machine frame; a work station attached to said machine frame; and a transport device with a transfer unit for supplying trays to said work station; wherein said transfer unit comprises a suction plate for transporting trays in a predetermined transport plane; and wherein said suction plate comprises a reception mold that is formed at least in part having a shape of an inner contour of an upper opening region of a tray positionable opposite of said suction plate on said transfer unit, wherein said reception mold is configured to receive and transport said tray so that said reception mold during transport in the transport plane of said tray is arranged in a positive-fit manner in said upper opening region of said tray and said reception mold aligns said tray in said transport plane in a predetermined position on said suction plate; wherein said reception mold is configured to suction said tray on an inner side of at least two different side walls of said tray; and wherein said reception mold comprises at least one sidewall and at least one bore disposed on said at least one sidewall to align with an inner wall surface of said upper opening region of said tray during transport of said tray when placed on said reception mold in a positive-fit manner, so that a vacuum applied to said suction plate through said at least one bore suctions said tray to apply a predetermined holding force to secure said tray in said predetermined position.

2. The packaging machine according to claim 1, wherein said reception mold has at least two opposing sidewalls and a plurality of bores disposed on each of said at least two opposing sidewalls of said reception mold for suctioning at least two opposing inner sides of said tray.

3. The packaging machine according to claim 1, wherein the reception mold comprises a plurality of sidewalls and said tray comprises a plurality of sidewalls, and each of said sidewalls of the reception mold includes at least one bore so that said reception mold can suction each sidewall of said tray on each inner side of said plurality of side walls of said tray.

4. The packaging machine according to claim 1, wherein said reception mold is formed as a centering member with respect to said upper opening region of said tray.

5. The packaging machine according to claim 4, wherein said reception mold comprises at least two opposing side walls and wherein at least a portion of each of said opposing sidewalls includes a slanted suction surface.

6. The packaging machine according to claim 1, wherein said suction plate comprises a folding device which is configured to form a sealing flange on said tray when said tray is arranged on said reception mold.

7. The packaging machine according to claim 6, wherein said reception mold is formed as part of said folding device.

8. The packaging machine according to claim 7, wherein said folding device comprises a forming plate on which said reception mold is adjustably mounted.

9. The packaging machine according to claim 8, wherein said reception mold is retractable at least in part into said forming plate.

10. The packaging machine according to claim 8, wherein said suction plate comprises a pressure element configured to move said reception mold toward said forming plate for a folding process.

11. The packaging machine according to claim 1, wherein said suction plate comprises a dynamic pressure test unit.

12. The packaging machine according to claim 1, wherein said suction plate is adjustably mounted with a linear drive configured to adjust a position of said suction plate in a direction in or opposite to a working direction of said packaging machine between a receiving position, in which trays can be transferred to said suction plate, and a transfer position, in which trays transported by said suction plate can be transferred to said workstation.

13. The packaging machine according to claim 12, wherein said linear drive comprises a guide oriented in said working direction of said packaging machine on said machine frame and a carriage that is adjustably mounted thereon and to which said suction plate is attached.

14. The packaging machine according to claim 1, wherein said suction plate comprises an upper part, a lifting plate movably arranged inside said upper part and connected to said reception mold, a controllable pressure diaphragm configured to raise said lifting plate, and a forming plate positioned between said lifting plate and said reception mold, and wherein said pressure diaphragm is operable to raise said lifting plate upwardly away from said forming plate to thereby raise said reception mold when said tray is on said reception mold so that an upper end of said tray is foldable against said forming plate to form a sealing flange on said tray.

15. The packaging machine according to claim 14, wherein said forming plate defines a receptacle configured to receive said reception mold when said lifting plate and said reception mold are raised.

16. A method for supplying trays to a work station of a packaging machine, the method comprising: providing a suction plate with a reception mold arranged thereon, wherein the reception mold is formed at least in part having a shape of an inner contour of an upper opening region of a tray being used in the packaging machine; engaging the tray in the upper opening region of the tray with the reception mold at least in part in a positive-fit manner during transport of the tray in a transport plane of the tray; aligning the tray in a predetermined position on the suction plate in the transport plane; and applying a vacuum to the suction plate through at least one bore disposed on at least one side wall of the reception mold to apply a predetermined holding force on the tray on at least one inner wall surface of the tray to secure the tray in the predetermined position.

17. The method according to claim 16, further comprising the step of folding over a sealing flange on the tray, along a pre-perforated edge of the upper opening region of the tray, when the tray is positioned in an aligned manner on the reception mold using a folding device of the suction plate.

18. The method according to claim 16, further comprising the steps of applying a dynamic pressure to the tray and checking the dynamic pressure applied to the tray using a dynamic pressure test unit provided on the suction plate.

19. The method according to claim 16, wherein the suction plate is a vacuum gripper, and further comprising the steps of transporting a plurality of the trays in or opposite to a working direction of the packaging machine from a receiving position, in which the trays are transferred to the suction plate, to a transfer position, in which the trays are transferred from the suction plate to the work station.

20. The method according to claim 16, wherein the suction plate comprises an upper part, a lifting plate movably arranged inside the upper part and connected to the reception mold, and a forming plate positioned between the lifting plate and the reception mold, and the method further comprises moving the lifting plate upwardly away from the forming plate to thereby raise the reception mold when the tray is on the reception mold so that an upper end of the tray is folded against the forming plate to form a sealing flange on the tray.

Description

DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) In the following, an advantageous embodiment of the present invention will be explained in more detail making reference to a drawing, in which the individual figures show:

(2) FIG. 1 is a schematic side view of one embodiment of a packaging machine in accordance with the teachings of the present disclosure;

(3) FIG. 2 is a perspective view of one embodiment of a packaging machine in accordance with the teachings of the present disclosure, that shows the suction plate employed for the transport of trays;

(4) FIG. 3 is a perspective view of one embodiment of a suction plate in accordance with the teachings of the present disclosure in an isolated view;

(5) FIG. 4 is a perspective view of the suction plate according to the embodiment of FIG. 3 showing a plurality of trays positioned thereon;

(6) FIG. 5 is a perspective view of another embodiment of a suction plate in accordance with the teachings of the present disclosure in an isolated view;

(7) FIG. 6 is a top perspective view of the suction plate of FIG. 5 showing the configuration in a transparent manner with trays positioned thereon;

(8) FIG. 7 is an end view of an embodiment of the suction plate in accordance with the present disclosure showing a folding device and a plurality of trays positioned thereon having an un-bent edge region; and

(9) FIG. 8 is an end view the suction plate from FIG. 7 with trays positioned thereon having the edge bent.

DETAILED DESCRIPTION OF THE INVENTION

(10) The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. For purposes of clarity in illustrating the characteristics of the present invention, proportional relationships of the elements have not necessarily been maintained in the drawing figures.

(11) The following detailed description of the invention references specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The present invention may be defined by the appended claims and the description is, therefore, not to be taken in a limiting sense and shall not limit the scope of equivalents to which such claims are entitled.

(12) FIG. 1 shows a schematic view of a packaging machine 1 embodied in the form of a thermoforming packaging machine T. Packaging machine 1 comprises a work station A formed as a forming station 2, a sealing station 3, a transverse cutting device 4 as well as a longitudinal cutting device 5. They are arranged in this order along a working direction R on a machine frame 6.

(13) Attached to machine frame 6 of packaging machine 1 on the inlet side is a feed roller 7 from which a base film U as lower packaging material 8 is withdrawn. Base film U is transported by way of an advance device, not shown, into forming station 2. Two packaging trays M are formed into base film U using forming station 2 by way of a thermoforming process taking place there. Packaging trays M can be transported onward to a loading stretch 15 where they can be filled manually or automatically with a product 16. Downstream of loading stretch 15, packaging trays M filled with products 16 are transported onward to a sealing station 3. Packaging trays M can be sealed by sealing station 3 with a top film O which forms an upper packaging material 10, so that sealing top film O onto packaging trays M produces sealed packagings V which are separated by way of transverse cutting device 4 and longitudinal cutting device 5 and can be transported away using a discharge device 13.

(14) Furthermore, packaging machine 1 shown in FIG. 1 comprises a controls terminal 9 at which process parameters can be set for the respective work stations provided at packaging machine 1. Controls terminal 9 comprises a control unit 11 which is shown only schematically. Control unit 11 is configured to perform computing operations, in particular in real time during the production process, in order to control packaging machine 1 based on processes, i.e. to possibly have respective process parameters of packaging machine 1 adjusted in relation to the process.

(15) Packaging machine 1 illustrated in FIG. 1 furthermore comprises a transport device 12 with a transfer unit 14 which is associated with workstation A and with which trays supplied from outside packaging machine 1 can be received within machine frame 6, transported onward and be transferred to forming station 2 positioned in the image plane of FIG. 1 upstream adjacent thereto. Transport device 12 could there alternatively be positioned in working direction R, in particular, also upstream of forming station 2. Transport device 12 is configured to continuously supply trays to forming station 2 during the manufacturing process which are combined with packaging trays M produced therein to create a (composite) packaging lower part VU.

(16) FIG. 2 shows a perspective view of transport device 12 integrated into machine frame 6 of packaging machine 1. According to FIG. 2, transport device 12 is transferred a plurality of trays 17 in a predetermined format F by feeding device 15, presently in a 22 format, from outside machine frame 6 of packaging machine 1. Trays 17 in FIG. 2 are formed as cardboard trays K, but can also be made of a different material.

(17) According to FIG. 2, trays 17 are transferred in the predetermined format F to a lifting mechanism 18 of transport device 12 mounted vertically adjustable along lifting direction C within machine frame 6. Lifting mechanism 18 is adapted to lift trays 17 positioned thereon for transferring trays 17 to transfer unit 14 positioned thereabove in a receiving position P1. The transfer unit 14 shown in FIG. 2 is adjustably mounted in or against the working direction R of the packaging machine 1 between the receiving position P1, in which the trays 17 can be transferred thereto, and a transfer position P2 along a transport plane E, in which trays 17 transported by the transfer unit 14 can be transferred to the forming station 2.

(18) According to FIG. 2, transfer unit 14 is configured as a suction plate 19. Suction plate 19 is mounted adjustable between receiving position P1 and transfer position P2 by a linear drive 20 in or opposite to working direction R of packaging machine 1. Linear drive 20 is equipped with a guide 21 oriented in working direction R of packaging machine 1 on machine frame 6 and a carriage 22 that is displaceably mounted thereon and to which suction plate 19 is attached Furthermore, an electric motor 64, for example, a servo motor, adapted to control an adjustment motion of suction plate 19 is preferably attached to machine frame 6. The operation of electric motor 64 can be coordinated by control unit 11 of packaging machine 1.

(19) The configuration shown in FIG. 2 shows that suction plate 19 as such is moved to and fro only horizontally in transport plane E for continuously supplying trays 17 received thereon to forming station 2 for further processing with packaging recesses M formed thereon.

(20) FIG. 3 shows suction plate 19 according to one variant in an isolated view. Suction plate 19 shown in FIG. 3 comprises a plate-shaped upper part 23 with which suction plate 19 can be attached to carriage 22 (see FIG. 2). Furthermore, suction plate 19 comprises a plate-shaped center part 24 which is connected to upper part 23. Several reception molds 25 extend from center part 24 on a side facing away from upper part 23. Reception molds 25 are shaped in such a way that, with regard to trays 17 that are provided to them for transport, they can at least in part receive them as a negative mold in a positive-fit manner in their upper opening region 26.

(21) Reception molds 25 can each be available separately or coupled to center part 24 as an exchange or retrofit attachment W for suction plate 19 in order to convert suction plate 19 for flexible use with respect to different tray geometries. Reception molds 25 shown in FIG. 3 are each configured as hollow bodies H in particular for reducing the weight of suction plate 19.

(22) FIG. 4 shows suction plate 19 from FIG. 3 with trays 17 received thereon in predetermined position X. According to FIG. 4, trays 17 received each have a bowl-like trough shape MF with an upper opening region 26 into which respective reception molds 25 immerse in a positive-fit manner.

(23) Upper opening regions 26 formed on respective trays 17 have an inner contour 27 which corresponds at least substantially to the formation of respective side walls 28 (see FIG. 3) of reception molds 25. According to FIG. 3, respective side walls 28 of reception molds 25 (see FIG. 2), which are oriented towards the side of machine frame 6, are slanted so that they have a slanted suction surface 29. Reception molds 25 are configured according to FIG. 3 and FIG. 4, in particular, as centering members Z, in order to possibly compensate for a slight offset of supplied trays 17 when they are received at suction plate 19. Reception molds 25 designed in particular as centering members Z aim to ensure that trays 17 placed thereonto can be received in a precise position on suction plate 19, so that further work steps, for example, a folding operation KV described in the context of FIG. 7 and FIG. 8, are promoted apart from the actual transport purpose.

(24) Furthermore, FIG. 3 shows that bores 30 are formed along respective side walls 28 of reception molds 25. During transport of trays 17 which are attached in a positive-fit manner on reception molds 25, respective bores 30 abut in sections against the former's inner wall surface 31 of upper opening region 26, so that a vacuum VK applied to suction plate 19 via bores 30 of respective reception mold 25 suctions tray 17 attached thereto by way of a predetermined holding force P in order to align trays 17 in a predetermined position X on suction plate 19, i.e. to transport them in the predetermined format F and transfer them to forming station.

(25) FIG. 4 also shows that respective trays 17 are received by suction plate 19 both in a positive-fit as well as in a force-fit manner. The positive-fit engagement is achieved by way of reception molds 25 produced as negative vacuum molds. The force-fit engagement for transporting trays 17 is supplied by vacuum VK applied to the respective inner wall surface 31 of trays 17.

(26) FIG. 5 shows suction plate 19 according to another variant for transporting a format F of trays 17 that is different than is shown by way of suction plate 19 described in the context of the previous figures.

(27) According to FIG. 5, a total of nine wedge-shaped trays 17, which can be used, for example, for packing triangular slices, can be received at suction plate 19. Trays 17 are there transported by way of suction plate 19 in a 33 format.

(28) The technical principle, according to which trays 17 can be secured to suction plate 19 both by positive-fit engagement at their upper opening region 26 and by force-fit engagement based on vacuum VK applied in this region, is also given in FIG. 5.

(29) Formed in suction plate 19 of FIG. 5 is a plurality of bores 30 in a plate member 32 as well as in respective reception molds 25 to distribute vacuum VK applied to suction plate 19 for evenly securing trays 17.

(30) FIG. 6 shows several connection channels 33 formed in plate part 32 of suction plate 19 and respective connections 61 which deliver vacuum VK generated at suction plate 19 all the way to bores 30 formed on side walls 28 of reception molds 25. Vacuum VK applied via the respective connection channels 33 and/or connections 61 can be selectively directed and blocked at individual reception molds 25 by way of suitable valve control.

(31) FIG. 7 shows suction plate 19 with folding device 34 formed integrally thereon. Folding device 34 comprises an adjustably mounted lifting mechanism 70 integrated into suction plate 19. Lifting mechanism 70 comprises a lifting element 42, for example, in the form of a plate which is arranged movable inside upper part 23 formed to be hollow in part, and a pressure element 43 arranged therebelow which is present in particular in the form of an inflatable membrane 46.

(32) Lifting element 42 is connected by way of connection pins 47 to reception molds 25. Connection pins 47 pass through a forming plate 37 of folding device 34 embodied for a folding operation or process KV (see FIG. 8). Lifting element 42, which is positioned above forming plate 37, and reception molds 25, which are attached to lifting element 42 by way of connection pins 47 and positioned on a side of forming plate 37 facing away, form a functionally coherent module of folding device 34.

(33) In the pressure-loaded state, membrane 46 raises lifting element 42 upwardly away from forming plate 37. As a result, reception molds 25 coupled thereto for folding operation or process KV are raised at the same time for producing a sealing flange 36 (see FIG. 8) on trays 17 placed thereon. In the unpressurized state, lifting element 42 rests on an upper side 50 of forming plate 37. Reception molds 25 are accordingly in an extended position 38 shown in FIG. 7. In this position 38, reception molds 25 are positioned in a spring-loaded manner by way of respective spring elements 49. The jointly acting spring rate of respective spring elements 49 can be matched to the pressure-loaded operation of membrane 46 in such a way that a predetermined folding stroke KH indicated in FIG. 8 is obtained.

(34) According to FIG. 7 and FIG. 8, sealing flange 36 is formed for respective trays 17, which are arranged on reception molds 25, along an edge 35 of respective upper opening region 26 formed thereon.

(35) For the production of respective sealing flanges 36, reception molds 25 can be at least in part retracted at forming plate 37 disposed thereabove into receptacles 48 formed thereon in order to draw trays 17 arranged thereon toward forming plate 37.

(36) FIG. 8 shows that trays 17 arranged on reception molds 25 are deformed along their edge 35 by folding stroke KH, as a result of which sealing flange 36 is formed on respective trays 17.

(37) Suction plate 19 shown in FIG. 7 holds reception molds 25 arranged thereon in a spring-loaded manner in extended position 38, in which trays 17 are transferred without sealing flange 36 formed thereon to suction plate 19. FIG. 8 shows respective reception molds 25 in a retracted position 39, in which reception molds 25 are drawn into corresponding receptacles 48 of forming plate 37 disposed thereabove by way of lifting mechanism 70 which is now pressure-loaded against the spring preload. By immersing respective reception molds 25 into receptacles 48 of forming plate 37 provided for this purpose, folded edge 35 shown in FIG. 7 is deformed in such a way that respective sealing flanges 36 shown in FIG. 8 are produced on trays 17.

(38) According to FIG. 7 and FIG. 8, bending grooves 45 are formed on forming plate 37 adjacent to respective receptacles 48 and support the folding operation or process KV of sealing flanges 36. A circumferential abutment edge 44 formed at respective receptacles 48 also has a positive effect on the creation of a precise sealing flange 36.

(39) Furthermore, FIGS. 7 and 8 show that suction plate 19 shown therein also comprises a dynamic pressure test unit 41. Dynamic pressure test unit 41 is formed on forming plate 37 in such a way that it can be verified in particular whether a tray 17 is properly positioned on suction plate 19 for a transfer process to work station A. It can also be verified by way of the dynamic pressure test unit 41 whether sealing flange 36 has been folded within tolerance limits.

(40) Transport device 12 employed in the invention, including suction plate 19 employed according to the invention, can be used at different locations along packaging machine 1 for supplying respective trays 17 that are fed to packaging machine 1 from outside for a further processing process performed there, for example, for combining with packaging trays M thermoformed at forming station 2. In particular, transport device 12 can be positioned, when viewed in working direction R of packaging machine 1 of FIG. 1, upstream or downstream of forming station 2 configured as work station A, for manufacturing trays 17 corresponding to packaging trays M produced there for producing packaging lower parts VU combined from trays 17 and packaging trays M. (see FIG. 1). Respective packaging lower parts VU produced in forming station 2 are then transported onward quasi as a tray composite to loading stretch 15.

(41) Transport device 12 used in the invention is not restricted to the use at a thermoforming packaging machine T according to FIG. 1, but can also be used in an advantageous manner at other types of machines, such as tray sealers.

(42) From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure. It will be understood that certain features and sub combinations are of utility and may be employed without reference to other features and sub combinations. This is contemplated by and is within the scope of the claims. Since many possible embodiments of the invention may be made without departing from the scope thereof, it is also to be understood that all matters herein set forth or shown in the accompanying drawings are to be interpreted as illustrative and not limiting.

(43) The constructions and methods described above and illustrated in the drawings are presented by way of example only and are not intended to limit the concepts and principles of the present invention. Thus, there has been shown and described several embodiments of a novel invention.

(44) As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. The terms having and including and similar terms as used in the foregoing specification are used in the sense of optional or may include and not as required. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow.