Abstract:
A plant for manufacturing and packaging tubes feeds the tubes via a conveyor belt to a packaging station, where they are packaged to form larger units. The foil strip is a dual or multiple-strip, cut by at least one partitioning blade into individual webs respectively welded in parallel planes to form endless tubes and cut by transverse cutters. The tubular bodies are assembled into a larger transfer group and jointly transferred to a turn table including a corresponding number of mandrels. The turn table conveys them jointly and stepwise to stations for fitting the shoulder portion with a threaded neck and the closure cap. The finished tubes are deposited on a discharge belt and fed to control regions for checking. Flawless tubes are received by the discharge belt and fed continuously to a tray.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Applicant claims priority under 35 U.S.C. §119 of German Application No. 102 37 839.8 filed on Aug. 19, 2002. Applicant also claims priority under 35 U.S.C. §365 of PCT/EP2003/008481 filed on Jul. 31, 2003. The international application under PCT article 21 (2) was not published in English. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a plant for manufacturing and packaging tubes consisting of a tubular body consisting of at least one plastic foil and, connected at one end thereof a shoulder portion with a threaded neck, fitted with a closure cap, the tubes being fed via a conveyor belt to a packaging station, where they are packaged to form larger units. 
     2. Description of the Related Art 
     This process is normally performed in two stages. In a first step tubular bodies are manufactured from a laminated foil or from an extruded hose, which are fitted with a shoulder portion comprising a threaded neck and a closure cap. In this case, prior to screwing on the closure means, an originality membrane may be applied to, usually welded onto the withdrawal aperture of the threaded neck. In a second step the tubes manufactured in this manner are then fed, often by means of a conveyor belt, to a packaging machine, where they are packaged to form larger units, and are optionally fed, after further transportation and/or storage, to a filing operation for filling the tubes with a product. After filling, the tubes are closed or sealed at the filling outlet in order to be then once again packaged into larger units for onward transport. 
     The manufacture and filling of the tubes is performed at a rate of about 80 to 200 tubes/minute, in which context packaging into larger units, in particular in low-wage countries, is performed manually, in which case, at the time of packaging the still empty tubes, visual quality control is performed simultaneously. In particular in countries with high price structures packaging of the still empty tubes, or, as the case may be, even the filled tubes, is done automatically by means of complicated transfer systems—usually into boxes. In this case inspection and/or quality control is performed automatically, which prevents manufactured tubes with defects to be packaged or fed to a filing plant. 
     During the filling operation the empty tubes are removed from the respective packaging either manually or by gripper means, even multiple grippers and are conveyed to the charging station of a fining machine. From the charging station the tubes normally reach a plurality of stations, e.g. by means of revolving tube holding devices, in which case a filling material is passed through the open end in one station or, optionally, even further stations, each filled tube being closed, e.g. welded, at the filling outlet, causing the filled product to be sealed hermetically in the tube. The filled and sealed tubes are subsequently removed manually or automatically from the filling machine and are optionally passed on to an end consumer in repackaged forum 
     This type of manufacture and packaging provides a certain flexibility at the filling site, but suffers from a number of drawbacks, which are to be seen, on the one hand, in the complicated logistics and transfer technology, in the risk of the packaged, empty tubes collecting dust and dirt, inter alia by frequent contact with the transfer devices, the very often required disposal of the packaging containers used, mainly cardboard boxes, and the required storage, necessitating dead capital on the one hand, and causing increased transport costs on the other. 
     SUMMARY OF THE INVENTION 
     It is the object of the invention to provide, on the one hand, plants, which permit, for example, the manufacture of 450-500 tubes/minute having tube diameters e.g. of preferably 22 to 40 mm, or larger or smaller and which permit the arrangement of this quantity of manufactured tubes in reusable, transportable packaging means—even for filling—without having to be repackaged. 
     This object is attained by a plant for manufacturing and packaging tubes formed of a tubular body including at least one plastic foil and, connected at one end thereof, a shoulder portion with a threaded neck, fitted with a closure cap. The tubes are fed via a conveyor belt to a packaging station, where they are packaged to form larger units. The foil strip is a dual or multiple-strip, cut by one or a plurality of partitioning knives into individual webs, which are in each case welded in parallel planes to form endless tubes and which are cut to the desired tube length by transverse cutters. The tubular bodies manufactured parallel to one another are then assembled into a larger transfer group and are jointly transferred to a turn table comprising a corresponding number of mandrels, the turn table conveying them jointly and stepwise to stations for fitting the shoulder portion with a threaded neck and the closure cap, whereupon the finished tubes are deposited on a discharge belt, formed of at least two toothed belts situated parallel next to one another and comprising transport prisms, the partitioning of which corresponds to that of the mandrels on the turn table, and being fed to control regions for examining the tubes and the flawless tubes being received by the discharge belt by means of rotatable suction prisms corresponding to the spacing of the transport prisms and being fed continuously to a tray. 
     Advantageous embodiments are discussed below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is elucidated in detail in what follows by way of an embodiment of a plant for manufacturing and packaging tubes with reference to the figures. There is shown in: 
         FIG. 1  a plant in longitudinal elevation; 
         FIG. 2  the plant according to  FIG. 1  viewed from the top; 
         FIG. 3  the plant according to  FIG. 1  in cross-section with a double-roll; 
         FIG. 4  a schematic representation of a tube collecting device; 
         FIG. 5  a discharge belt made of two co-acting toothed belts; 
         FIG. 6   a - e  the transfer of an individual tube; 
         FIG. 7  tube trays. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       FIG. 1  shows the longitudinal side of a plant according to the invention viewed from the side. On its left end face  1  a double roll  3  (see also  FIGS. 2 and 3 ) of a foil strip  4  is arranged on an axis  2  in a rotatable—optionally also driven—manner. As a result of this front end arrangement space is saved in the plant in and on its longitudinal side. A partitioning knife  5  cuts the double-web  3  of the foil strip  4  into two individual webs  6   a  and  6   b . Each individual web  6   a ,  6   b  is deflected by a deflecting rod  7   a ,  7   b,  optionally with guiding rolls, by 90° on the longitudinal side of the plant. The deflection is performed such that the individual webs  6   a ,  6   b —as shown in FIG.  1 —are guided onwards in two superimposed planes. Each individual web  6   a ,  6   b  is associated with a moulding bell  8 , a welding head  9  as well as pressing and cooling devices  10 , by means of which the deformation into a tubular body  11  (endless tubes  11   a ,  11   b ) is performed, in which context the provision here of a longitudinal overlap seam, e.g. by welding, may be performed in this case as well. 
     The foil strip  4  may already comprise print or character images (not shown) and may also be designed as a triple or multiple strip, in which case further partitioning knives  5  and further planes for manufacturing the respectively required number of endless tubes would have to be provided. 
     According to the desired length of the tubular bodies  11  or of a printed image the endless tubes  11   a ,  11   b  are separated by way of transverse cutters  12   a ,  12   b , having e.g. a size control, into tube body sections  13   a ,  13   b  having the respectively desired length A transfer device  14  including suction prisms  15 , which may be bent around by 45°, takes over two tube body sections  13   a ,  13   b  each in a cyclical operation until altogether six tube body sections  13   a ;  13   b  are assembled to form a “transfer group”. 
     The transfer device  14  then guides the “transfer group” of six tube body sections  13   a,    13   b  into a transfer position  16 , turned by 90°, where they are taken over by a horizontally moving vacuum slide-on holding device  17 , i.e. at any one time six tube body sections  13   a ,  13   b  are transferred in this process. The transfer device  14  consists of two single transfer belts  18   a  and  18   b  operating independently from one another, each comprising six suction prisms  15   a ,  15   b . These single transfer belts  18  are so controlled and driven that a pulse wise receiving of two tube body sections  13   a ,  13   b  at a time, in the present case in a cycle of 450/2=225/minute and likewise a pulse-wise releasing, in the present case in a cycle of 450/6=75/minute is ensured and/or possible in the case of six tube body sections  13   a ,  13   b  at a time. These two systems operate at a 180° phase shift alternating with each operating side. 
     Each slide-on holding device  17  performs a linear up-and-down movement, in order e.g. to move the six tube body sections  13   a ,  13   b  from the take-over position  16  of the transfer device  14  into a slide-on position  16 ′ congruent (coaxial) in relation to mandrels  19  of a turn table  20 . In this context the six tube body sections  13   a ,  13   b  each are simultaneously and jointly pushed onto the mandrels  19  by means not shown, e.g. slide-on tappets. 
     The turn table  20  is so designed as to convey six mandrels  19  at a time in one step or cycle one after the other, to, for example, eight stations A-H (see  FIG. 1 ). The turn table  20  causes the mandrels  19  to be fed in one step, one after the other, to the individual stations A-H comprising devices for assembling, in the present case six, complete tubes. At the stations A-H all respective mandrels  19  are provided with the required components or are acted upon by external tools. 
     In the embodiment shown, at station A six shoulder portions  21  with a threaded neck are simultaneously fitted onto the free end of the mandrels  19 , at station B six tube body sections  13   a ,  13   b  are slid over the shoulder portions  21  onto the mandrels  19  by the vacuum created by the slide-on holding device  17 , i.e. positioned in relation to another, in the station C the tube shoulders  21  are pre-heated, which in position D are welded onto the tube body sections  13   a ,  13   b  by way of HF-induction heating, while in station E membranes (not shown) for safeguarding content originality are stamped onto the discharge outlet in the shoulder portions  21 , in which context this station E may, for example, also be used for cooling the welded shoulder portions  21 , while in station F the tube closure caps  22  may be screwed on, which may then be readjusted in station G, e.g. to a precise torque of 35 Ncm, whereafter finally in station H the now complete tubes  23  are withdrawn or removed from the mandrels  19  of the turn table  20 , in order e.g. to be placed onto continuously-operating discharge belt  24 . 
     The discharge belt  24  shown in  FIG. 5  consists of two toothed belts  25   a  and  25   b,  toothed on the inside, arranged parallel next to one another and equipped with transport prisms  26 . The transport prisms  26  consist of two partial prisms  26   a ,  26   b,  jointly fixed on the toothed belts  25   a ,  25   b , serving as transport belts. Each of the two toothed belts  25   a ,  25   b  is tensioned and guided through a toothed driving pulley  27   a  or  27   b  and a freely mounted deflection pulley (not shown). In this case the driving pulleys  27   a  and  27   b  are arranged on a joint drive shaft  28  and by means of an adjusting device  29  are arranged on the drive shaft  28  in a manner to be adjustable in opposite directions in respect of their relative angle or phase position. By adjusting the angle position of the driving pulleys a linear displacement of the two toothed belts  25   a ,  25   b  is brought about, making it possible at the same time to optimally adapt all transport prisms  26  in a very simple and time-saving manner to the respective, freely-selected tube diameters. This results in the setting of the geometrical axis of all tubes  23  to be very simple for all tube diameters and always at the same level. The arrangement of the transport prisms  26  corresponds in the present example to the spacing of the mandrels  19 , being 95 mm. As in the present example six mandrels  19  are provided, feeding of the shoulder portions  21  and of the tube closure caps  22  is likewise performed six-fold, although other numbers, e.g. four or eight, are likewise possible. 
     On the discharge belt  24  shown in  FIG. 4  the tubes  23  may, for example, pass through four different control and discharge zones, situated e.g. in the region  30  along part or all of the length of the upper portion of the discharge belt  24 . The four control and discharge zones may, for example, be: a first control for tubes without closure caps; a second control serving as statistical quality control; a third control for unusable reject tubes and a fourth control for good (usable) tubes. During the statistical quality control process sample tubes may be withdrawn automatically at freely selectable time intervals. Reject tubes or defective tubes  23 ′ may be ejected at the end of the discharge belt  24 . 
     At the end of the linear region of the discharge belt  24  a collecting device  31  is arranged comprising e.g. six rotating suction prisms  32  by means of which the good (flawless) tubes  23  may be received continuously, e.g. in trays  34 . 
     This proposed four-way system with the selective ejection of tubes  23  for different uses at different locations along the discharge belt  24  makes it possible, in each case as a function of the respective quality properties or the type of the tubes  23 —without any manual intervention—to separate the suitable tubes  23  from the unsuitable tubes  23 ′. 
     The six suction prisms  32  in the region  31  ( FIG. 4 ) are arranged in the same spacing relationship as the pure transport prisms  26 . By individually controlling the rotary movement of the six suction prisms  32  all tubes  23  fed to the discharge belt  24  may, therefore, be collected continuously according to freely selectable and adjustable criteria, e.g. in such a manner that only absolutely flawless tubes  23  are taken. 
     A possibility for control presents itself in this context by way of recording the respective process parameters or production parameters, in relation to a tube  23 , actually prevailing when passing through the various work stations A to H, each tube  23  transported on the discharge belt  24  subsequently being examined in relation to these parameters. The result may also be accurately assigned to each examined tube  23 . As a result, the temporary history file created for each tube  23  serves as control means, all essential production parameters, e.g. in a production data set, being assigned to said history file and defective tubes  23 ′, according to set elimination criteria, being eliminated or monitored at a suitable location. When monitoring, it can be established whether e.g. the welding temperature or the pre-heating was performed at the desired set value or whether it was insufficient. If the predetermined set value was not attained and defective tubes  23 ′ were manufactured as a result thereof, the latter must be eliminated. A missing closure cap  22  on a tube  23  may likewise be detected. Defective or incomplete tubes  23  are removed at a defined location. The described control process ensures that only absolutely flawless tubes  23  are conveyed to the collecting device  31 . 
     The tube transfer from the mandrels  19  of the turn table  20  to the continuously operating discharge belt  24 , shown in  FIG. 4 , is performed in a deposit region  33  or a deposit station for in each case all six—unit forming—mandrels  19  of the turn table  20 . They may, e.g. be withdrawn from the mandrels  19  by removal tongues, not shown, and, where applicable, be deposited in transport prisms  26  by a rotatable holding device  32 ′. A turning motion of the holding device  32 ′ adapted to the advance movement of the discharge belt  24  provides a complete, smooth transfer, in each case all tubes  23  of one unit (in the present case six) being off-loaded and reaching the discharge belt  24 . 
     Selection in terms of the quality of the tubes  23  manufactured according to the above described criteria is only performed in the on-following zone  30  of the discharge belt  24  (see  FIG. 4 ). 
     In this on-following zone  30  only the flawless tubes  23  are collected, in each case as a unit—in the present case six tubes  23 —, by means of a collecting device  31  and only after a complete unit has been obtained, i.e. in the present example six flawless tubes, are they transferred jointly and continuously into special trays  34 . 
     The collecting device  31  comprises six stations with six rotatable holding devices  32 A,  32 B,  32 C,  32 D,  32 E and  32 F including suction prisms. For the sake of simplicity,  FIG. 6  shows only one holding device  32 A including a suction prism. All holding devices  32  including suction prisms are arranged parallel and above the discharge belt  24 . In the respective transfer or take-over position, in relation to the discharge belt  24 , each holding device  32  comprises a suction prism with a cavity, directed upwardly in the respective locking or neutral position (see  FIG. 6   a ). If a tube  23 , recognised to be usable, approaches the station  32 A at rectilinear velocity V 1  on the collecting belt  24  in the transport prism  26 A, the suction prism of the holding device  32 A turns by the peripheral speed U 1  and the tube  23 , as a result of the suction force applied by the bores  35 , is seized by means of the suction prism of the holding device  32 A. In orders to ensure a perfect take-over of the tube  23 , the peripheral velocity U 1  is adapted as closely as possible to the rectilinear velocity V 1  or is selected to equal the latter. The bores  35  in the holding device  32 , terminating in its cavity, are connected to a suction source, not shown, whereby the tube  23  is removed from the transport prism  26 A. 
     In the momentary state shown in  FIG. 4  as an embodiment, the next following good=flawless tube  23  has also been withdrawn from the transport prism  26 B at station  32 B by the holding device  32 B. 
     If a tube  23 ′, which has been found unusable in terms of the performed selection, approaches in the transport prism  26 C the next unoccupied holding device  32 C with its suction prism, the holding device  32 C does not turn and the defective tube  23 ′ remains on the discharge belt  24  and is ejected or disposed of at its outlet. 
     If the next tube  23  arriving on the discharge belt  24  in the transport prism  26 C is in order, the holding device  32 C with its suction prism turns and seizes the tube  23 , turning it in upward direction, so that in position  32 C a third flawless tube  23  is now present. The same procedure is followed until a fourth flawless tube  23  is obtained from the transport prism  26 A′ in the following position  32 D, then a fifth one from  26   b ″ in  32 E and finally a sixth one from  26 D′ in  32 F, i.e. until six flawless tubes  23  are present in all stations  32 A- 32 F of the collecting device  31 . The transport prisms  26 E and  26 F shown in an unoccupied state pass underneath the collecting device  31  without one of the rotatable holding devices  32  being activated. Thereafter all six tubes  23  arranged in the stations  32 A- 32 F are passed on jointly and, therefore, continuously, to a tray  34 , e.g. transferred by a vaguely indicated joint sliding device  36 . According to the successive charge, the tray  34  is then shifted in order to receive the next unit of flawless tubes  23 . This ensures that automatically only tubes  23  which have been graded as flawless end up in the tray  34 . 
     The collecting device  31  may also serve to “fill in gaps” in any desired tube transport system, e.g. a tube storage system. 
     The filled tray  34  is conveyed as such to any desired filling station, e.g. via conveyor belts, where the tubes  23  arranged in the tray  34  are filled with a product. It is also possible to perform filling only when the tubes  23  have already been removed from the tray  34 . It is obvious that the number of operations required may be clearly reduced by the invention and that they may also be automated, so that manual operation is not required.