Packaging machine

Abstract

A packaging machine comprises a transfer device for inserting a product into a package and a circulating leaflet supply device comprising a plurality of tong-like holders which are disposed in a row, for receiving one leaflet each, and for bringing the leaflet into the region of the transfer device between the product and the package such that it can be inserted together with the product into the package. An opening unit with at least one stop is disposed in the transport path of the holders for opening the holders to release the leaflet. The stop can be adjusted in dependence on an opening signal of a control device between an operative position opening the holders and an inoperative position in which the holders pass the stop without releasing the leaflet. A first detector device is thereby provided for detecting the insertion motion of the product into the package and for transmitting a corresponding insertion signal to the control device when the product is being inserted, wherein the control device generates the opening signal only when the insertion signal is present.

Description

[0001] The invention concerns a packaging machine comprising a transfer device for inserting a product into a package, and with a circulating leaflet supply device comprising a plurality of tong-like holders which are disposed in a row, for receiving one leaflet each, the leaflet supply device disposing the leaflet, in the region of the transfer device, between the product and the package, such that the leaflet can be inserted together with the product into the package, wherein an opening unit comprising at least one stop is disposed in the transport path of the holders by means of which the holders can be opened for releasing the leaflet, wherein the stop can be adjusted in dependence on an opening signal of a control device between an operative position which opens the holder and a non-operative position in which the holder passes the stop without releasing the leaflet.

[0002] A packaging machine of this type usually has a first circulating supply device for the package, e.g. a so-called folded box chain, and a second circulating supply device for the products, e.g. a so-called product chain. The motions of these two chains are synchronized such that the product can be inserted by an insertion plunger, transversely to the direction of motion of the chains, laterally into the folded box. For certain products, e.g. medication, an additional leaflet or side note must be inserted into the package. For this reason, one further circulating supply device is provided in the form of a so-called leaflet tong chain which supports several tong-like holders which each can receive and clamp one leaflet. A leaflet to be inserted into the package is moved between the product and the folded box by the leaflet tong chain and is carried along by the product through its lateral inserting motion to be inserted into the folded box. As soon as the product abuts the leaflet, the tong-like holder must be opened to release the leaflet. Towards this end, an opening unit is provided in the region of the transfer device, e.g. in the form of a stop or opening wedge, against which the tong-like holder abuts during its supply motion thereby opening the tong arms and releasing the leaflet.

[0003] During operation of the packaging machine, small irregularities are likely to occur, whereby the folded boxes are possibly supplied to the folded box chain or the products are supplied to the product chain in a discontinuous fashion such that either one or more sections of the folded box chain have no folded box or one or more sections of the product chain contain no product. A sensor detects when a folded box or a product is missing whereupon no product is inserted or the insertion plunger is not activated.

[0004] In older packaging machines, the opening wedge is rigidly installed in consequence of which the tong-like holder also opens when no product is being inserted into a folded box. It has turned out that the leaflet released in this case, can move randomly through the packaging machine and cause malfunction of the packaging machine as well as temporary stoppage, which requires time-consuming and expensive manual intervention. To solve this problem, DE 199 18 527 A1 proposes to bring the opening wedge out of the transport path of the tong-like holder into an inoperative position when required. In this fashion, the tong-like holder opens and releases the leaflet only when a folded box is actually present in the folded box chain and the product chain contains a product. When no folded box or no product is present, the opening wedge is removed from the transport path of the tong-like holder such that the tong-like holder with leaflet passes the opening wedge and is not opened thereby. The opening wedge then returns into its operative position to open the following tong-like holder if the conditions required therefor are met.

[0005] The cycling times provided in a modern packaging machine for one working cycle are only a few milliseconds. During this time, the conditions required for adjusting the opening wedge, at least with regard to the product and the package, must be detected and evaluated and the operating means must be activated to adjust the stop. The plunger inserting the product into the package is activated only when a product is present, when a leaflet is present which has the correct code, and when a package or folded box is present. The corresponding inquiries or detections are carried out in the packaging machine and the corresponding data is stored in a so-called shift register and can be queried therefrom. This data also forms the basis for the decision whether the tong-like holder is opened to release the leaflet or remains closed.

[0006] The packaging machine stores one data set for each package unit, comprising the product, the folded box and the leaflet, wherein the data set contains all essential conditions and control data of the package unit. Since a plurality of package units are processed simultaneously and pass through the packaging machine, the data sets are conventionally stored in a common data storage. The data storage is a shift register and the data sets within that shift register are shifted, i.e. displaced, within the shift register in time steps corresponding to the working cycle of the machine, i.e. to the changing position of the associated package unit in the packaging machine continuing up to the ejector station. The shift register is timed via a shift frequency strobe which is usually extracted from the product chain drive.

[0007] A packaging machine must be able to process products and packages of different formats and also different leaflet formats. The individual components of the transfer station of the packaging machine must be adjusted relative to each other in dependence on the product sizes, the package sizes and the leaflet sizes. The leaflet tong chain with the wedge opening the tongs, is usually adjusted relative to the product chain and/or the folded box chain when the format is changed. In consequence thereof, the point in time when the opening wedge is optionally brought from its inoperative position into its operative position (opening wedge time) is also adjusted relative to the shift timing of the shift register, which defines the start of a processing cycle of the packaging machine. Due to adjustment of the opening wedge time relative to the shift timing of the shift register, a situation may be created in which the two points in time coincide or are at least sufficiently close to each other that the control does not detect and process them as two independent signals. This situation can produce incompatible developments in the control and inadmissible operating states which can lead to stoppage of the packaging machine in response to malfunction. To eliminate the disturbance, the mechanical and electronic settings of the packaging machine and, in particular, of the leaflet tong chain relative to the product chain must be changed until safe operation is ensured. Such adjustment is possible since there is a certain time tolerance during transfer of the leaflet from the tong-like holder of the leaflet tong chain. Nevertheless, elimination of the disturbance is demanding and has a negative influence on the overall performance of the packaging machine.

[0008] It is the underlying purpose of the present invention to provide a method for controlling a packaging machine of the above-mentioned type, wherein adjustment of the stop or opening wedge relative to the product chain and/or the folded box chain produces no conflict between the shift time of the shift register and the opening wedge time.

[0009] This object is achieved in accordance with the invention with a packaging machine having the characterizing features of claim 1.

[0010] The invention is based on the principal idea that initiation of the opening motion of the tong-like holder is not directly based on the above-mentioned data of the shift register, rather indirectly, in that a first detector device detects the insertion motion of the product into the package and emits a corresponding insertion signal to the control device when the product is inserted. The control device generates an opening signal only when an insertion signal is present, i.e. when the product has actually been inserted, in response to which, the opening wedge is brought into its operative position in which it opens the tong-like holder.

[0011] An insertion motion of the product occurs only when the insertion plunger is initiated, which, in turn, depends on satisfying the above-mentioned conditions (leaflet present? Product present? Folded box present? Leaflet code correct?). When the first detector device determines that the insertion plunger is moved or the product is inserted, the above-mentioned conditions must all be met. The insertion signal then indicates whether or not the leaflet is to be released through opening the associated tong-like holder.

[0012] The first detector device can directly detect the insertion motion of the product. Alternatively, it is also possible that the first detector device detects the insertion motion of the insertion plunger abutting the product.

[0013] In a preferred embodiment of the invention, the first detector device comprises a first initiator, which can be initiated by any passing insertion plunger, and a second initiator which can be initiated only by an insertion plunger inserting the product. This embodiment is favourable in terms of control. The first initiator is preferably disposed upstream of the second initiator with respect to the transport direction and is crossed and triggered by every insertion plunger i.e. independently of whether the insertion plunger actually carries out an insertion motion to insert the product or if the insertion motion is suppressed through disablement of the insertion plunger. The insertion plunger crossing the first initiator resets an intermediate storage or mark to a value 0. When the insertion plunger subsequently starts an insertion motion of the product, it crosses the second initiator and triggers it thereby setting the intermediate storage to the value 1. Only when the intermediate storage has the value 1 is an insertion signal transmitted to the control device. The next insertion plunger resets the intermediate storage to 0 when the first initiator is triggered.

[0014] In a preferred embodiment of the invention, the initiators can be triggered by the insertion plunger without contact, which is the case, in particular, when the initiators are metal detectors, magnetic switches or light barriers which are triggered or switched by the insertion plunger.

[0015] In a preferred embodiment of the invention, the first detector device and the opening unit can be adjusted together as a unit in the transport direction of the leaflet supply device. Towards this end, the above-mentioned components are disposed on a common adjustable frame. This embodiment is advantageous in that adjustment of the opening unit for changing the format, e.g. when the product size is changed, simultaneously also displaces the first detector device with the two above-mentioned initiators by the same amount and the temporal association between the first detector device and the opening unit is maintained.

[0016] A further development of the invention may have an additional second detector device for detecting the position of the next holder to be opened and transmitting a corresponding holder signal to the control device. The second detector device determines that a holder has reached a predetermined position. The control device also evaluates whether the tong-like holder is to be opened or shall remain closed due to the received insertion signal and whether the holder to be opened is properly aligned. When both conditions are met, the stop or the opening wedge can be brought or held in the operative position through triggering of an actuating device to open the holder as determined by the second detector device. When the actuating device of the opening wedge is not activated, the tong-like holder passes the opening unit or the opening wedge without being opened. The leaflet is then removed from the holder and discharged or dispatched in a suitable manner at another position of the leaflet supply device, e.g. by means of a further stop.

[0017] When the format is changed, the second detector device is adjusted in the transport direction of the leaflet supply device, preferably as a unit together with the first detector device and the opening unit. In this fashion, the spatial and therefore temporal relationship among the components is also maintained after displacement.

[0018] In a further development of the invention, the stop is pretensioned by a spring into its inoperative position such that the controllable actuating device must be activated against the spring pretension to bring or keep the stop in the operative position when the conditions required for opening the tong-like holder and releasing the leaflet are met. The actuating device may be a pneumatic or hydraulic adjustment cylinder. In particular, the stop or the opening wedge can be adjusted, preferably displaced, substantially perpendicular to the transport supply device.

[0019] Further details and features of the invention can be extracted from the following description of an embodiment with reference to the drawing.

[0020] The single FIGURE shows a schematic representation of a transfer device in a packaging machine.

[0021] The FIGURE schematically shows a transfer device 10 of a packaging machine which comprises a folded box chain 28 (only schematically shown) extending in the direction of the arrow FK for receiving folded boxes or packages V, and a product chain 29 extending parallel thereto in the direction of the arrow PK with products P to be packaged. To simplify the illustration, the FIGURE shows only one package V and one product P. The motions of the folded box chain 28 and the product chain 29 are synchronized such that the product P can be inserted into the open package V via an insertion plunger 11 of the transfer device 10 acting transverse to the direction of motion of the chains 28 and 29. The insertion plunger 11 thereby follows an insertion curve EK.

[0022] A circulating leaflet tong chain 27 (transport path PZK) extends between (below and parallel to) the folded box chain 28 and the product chain 29, and carries a plurality of tong-like holders 15, 16 at regular intervals between the jaws of which one leaflet (not shown) can be clamped with upright alignment. The leaflet is guided such that it is positioned between the package V and the product in the region of the transfer device 10. When the product P is transversely inserted into the package V, the leaflet is carried along thereby and inserted into the package V. When the leaflet is inserted into the package V, the holder 15, 16 which clamps the leaflet must be opened. Towards this end, the transfer device 10 has an opening unit 12. The opening unit comprises an adjustable stop or opening wedge 13 which extends parallel to the transport path PZK of the leaflet tong chain 27 or the tong-like holders 15, 16. The opening wedge 13 has an associated actuating device 24 by means of which the opening wedge 13 can be adjusted substantially perpendicularly to the transport path PZK of the tong-like holders 15, 16 between an operative position and a withdrawn, inoperative position. The opening wedge 13 is thereby pretensioned into its inoperative position by a spring (not shown).

[0023] The tong-like holders 15, 16 disposed on the leaflet tong chain 27 conventionally have clamping jaws or tongs for clamping the leaflet. Each holder moreover has an axis extending transverse to the transport path PZK on which rollers 17 or 18 are rotatably disposed to form a stop part of the holder 15 or 16. The stop part with rollers 17 or 18 is oriented such that the latter abut the opening wedge 13 when it is in its operative position.

[0024] The FIGURE shows that the insertion plunger 11 has an associated first detector device 19 for detecting whether the insertion plunger is displaced to insert the product P. The first detector device 19 comprises a first initiator 19a which is triggered by each passing insertion plunger 11 and a second initiator 19b disposed behind the first initiator 19a in the transport direction PZK which is only triggered by an insertion plunger 11 which inserts the product P. The first initiator 19a resets an intermediate storage or mark to the value 0 as soon as an insertion plunger 11 passes or crosses it. When the insertion plunger 11 follows the insertion curve EK via points set by the shift register to thereby insert the product P, it also passes the second initiator 19b as a result of which, the intermediate storage or mark is set to the value 1. The first detector device 19 with the two initiators 19a and 19b is disposed on a plate 14 which is structurally connected to the opening unit 12. When the intermediate storage has the value 1, the first detector device 19 transmits a corresponding insertion signal to the control device 26 via a data line L.

[0025] Moreover, a second detector device 20 is provided close to the leaflet tong chain 27 in front of the opening unit 12, for detecting that the next tong-like holder to be opened has reached a predetermined position. The second detector device 20 transmits a corresponding holder signal to the control device 26 and the signals are processed in the control device 26. When the first detector device 19 has determined that the product P has been inserted and when the second detector device 20 determines that the next holder has reached its desired position, all required conditions for releasing the leaflet from the tong-like holder 15 or 16 are met. The control device 26 controls the actuating means 24 of the opening wedge 13 such that it is brought into its operative position. The holder 15 abuts against the opening wedge 13 and is opened to release the leaflet which is then carried along by the product P during its insertion motion and is inserted into the package V.

[0026] When the first detector device 19 determines that the product P is not inserted, all conditions which are required for correct transfer of the product P are not met. The second initiator 19b is not triggered and does not set the intermediate storage to the value 1 and no insertion signal is generated for the control device 26. The control device 26 detects that the opening wedge for the next tong-like holder should be brought into the inoperative position to ensure that the holder does not abut the opening wedge and is accordingly not opened. The leaflet remains in the tong-like holder and is removed and diverted at another point of the leaflet tong chain.

[0027] When the packaging machine is adjusted to another product format, the first detector device 19, the second detector device 20, and the opening unit 12 are commonly adjusted as a unit in the transport direction PZK of the transport supply device 27, while maintaining their mutual relative locations and orientations.

Claims

1. Packaging machine comprising a transfer device for inserting a product (P) into a package (V) and with a circulating leaflet supply device (27) comprising a plurality of tong-like holders (15, 16) which are disposed in a row, for receiving one leaflet each, and for bringing the leaflet into the region of the transfer device between the product (P) and the package (V), such that it can be inserted together with the product (P) into the package (V), wherein an opening unit (12) is disposed in the transport path of the holders (15, 16) having at least one stop (13) for opening the holders (15, 16) to release the leaflet, wherein the stop (13) can be adjusted in dependence on an opening signal of a control device (26) between an operative position opening the holders (15, 16) and an inoperative position in which the holders (15, 16) pass the stop (13) without releasing the leaflet, characterized in that a first detector device (19) is provided which detects the insertion motion of the product (P) into the package (V) and transmits a corresponding insertion signal to the control device (26) when the product (P) is being inserted, wherein the control device (26) generates an opening signal only when the insertion signal is present.

2. Packaging machine according to claim 1, characterized in that the first detector device (19) detects the insertion motion of an insertion plunger (11) abutting the product (P).

3. Packaging machine according to claim 1 or 2, characterized in that the first detector device (19) comprises a first initiator (19a) which can be triggered by each passing insertion plunger (11), and a second initiator (19b) which can be triggered only by an insertion plunger (11) inserting the product (P).

4. Packaging machine according to claim 3, characterized in that the first initiator (19a) resets an intermediate storage to the value 0 and the second initiator (19b), which is disposed downstream of the first initiator (19a) with respect to the transport direction, sets the intermediate storage to the value 1 when triggered, wherein the insertion signal is transmitted to the control device (16) only when the intermediate storage has the value 1.

5. Packaging machine according to claim 3 or 4, characterized in that the initiators (19a, 19b) can be triggered by the insertion plunger (11) without contact.

6. Packaging machine according to claim 5, characterized in that the initiators (19a, 19b) are formed by metal detectors, magnetic switches or light barriers.

7. Packaging machine according to any one of the claims 1 through 6, characterized in that the first detector device (19) and the opening unit (12) are adjustable as a unit in the transport direction (PZK) of the leaflet supply device (27).

8. Packaging machine according to any one of the claims 1 through 7, characterized by a second detector device (20) which detects the position of the next holder (15, 16) to be opened and transmits a corresponding holder signal to the control device (26).

9. Packaging machine according to claim 8, characterized in that the stop (13) can be brought into the operative position in dependence on the insertion signal and the holder signal.

10. Packaging machine according to claim 8 or 9, characterized in that the second detector device (20) can be adjusted, as a unit together with the first detector device (19) and the opening unit (12) in the transport direction (PZK) of the leaflet supply device (27).

11. Packaging machine according to any one of the claims 1 through 10, characterized in that the stop (13) is pretensioned by a spring into its inoperative position and the stop (13) has an associated controllable actuating device (24) with which the stop (13) can be brought into the operative position in opposition to the spring pretension.