Method for controlling a blister packaging machine

Translation of description of equivalent WO 2004065223 A1

Method for controlling a blister packaging machine

The invention relates to a method for controlling a blister packaging machine, which has at least one cyclically operating workstation in which during a working cycle at least one first adjusting motion for a time period T_Vα is executed, a subsequent treatment thereto state in which takes place a treatment of a product and / or material, over a period T_B is taken, then a second adjusting motion for a time r to T_v2 is performed and, if appropriate, an idle state for a period T_R product, where the periods Tvi, T_{B /} T_V2 and T_R and a resultant clock rate R (= cycles / min) are preset to the packaging machine and at least the cycle rate R transfer device by means of an input to a different cycle rate R_v is changeable.

A blister packaging machine conventional structure comprises a forming station, in a plastic or aluminum existing base film, a plurality of cup-shaped depressions are formed, in which in a subsequent filling one product, for example, a pharmaceutical tablet, is inserted. After the product supply, the bottom foil a sealing station is supplied. Immediately prior to or within the sealing station a cover sheet is supplied and sets listed on the bottom foil. By exposure to heat within the sealing station, the cover sheet is sealed tightly onto the bottom sheet, whereby the product is enclosed in the cup-shaped depression.

The forming station is intermittently and therefore discontinuously. The sealing station can be operated clock-wise either also, alternatively, it is also known to operate the sealing station continuously, wherein the transition from cyclical operation of the forming station and continuous loan operation of the sealing station of known equalization - devices occurs.

The performance of a blister packaging machine depends largely on the clock rate R, ie the number of cycles performed per minute. From the cycle rate R, the maximum available for a working clock cycle time T results_Max in milliseconds to T_raax = 60,000 / R [ms], that is at a cycle rate R of 75 cycles / min, the ma^¬ mum cycle time T_Max = 800 ms. A cycle curve of a corresponding working cycle is as simplified, polygonförmi - represented ges displacement time diagram in Figure 2, which will be discussed briefly below..

Within the maximum cycle time T_Max the cyclically described exaggerated form station, is to be assumed by way of example of the various movements and operations or treatments must perform. Starting from a basic or zero position at the beginning of the cycle (point 0 in Fig. 2), in the two mold plates, between which the to be formed bottom foil completely disassembled are driving, a first adjustment, namely the closing movement of the mold plates is performed first. The closing S_v is given of production technology and the closing movement is over a predetermined time period T_Vι carried out until point 1 (see Fig. 2) is reached, in which the mold plates are closed and have reached their final position.

The mold plates have then their treatment state is reached, in the example, a preheated plastic - base film over a period T_B is cooled, in addition there is a formation of the cup-shaped depressions in the bottom sheet in particular by means of compressed air or forming dies. At point 2 of stroke curve, the cooling treatment or the bottom sheet is completed and it is followed by a second adjustment movement, namely, the opening movement of the mold plates, which in turn across the path Sv (but in the opposite direction) over a period of time T_v2 takes place. At the end of the opening movement, that is, in point 3 of the cycle curve, the starting position is reached again. The open mold plates may then for a period T_R be kept in an idle state. The duration of the period T_R Hibernation is largely dependent on factors outside of the forming station and can be very short in the best case or even 0th

Once the mold plates are opened to a sufficient degree, the further transport of the bottom sheet may be initiated and executed. As shown in FIG. 2 is an example assumed that the further transport of the bottom sheet starts when the mold plates to the path S_v/ 2 are moved apart, ie it stands for the onward transport of the bottom sheet to the clock end nor a period t_Zι and from the beginning of the next cycle until the time at which the mold plates are again half closed, a time span t_z2 available, with a total journey - time T_z from the sum of t_Zι and t_z2 results.

In previous blister packaging machine the curves were get lost mechanically determined by rotating cam whose rotary motion derived from a central, driven main shaft, the so-called vertical shaft. In modern blister packaging machine the curves are stored in software and the motor drive of the adjusting via servomotors which are addressed by an electronic control system and the corresponding software.

When setting up a blister packaging machine to a particular blister format usually the moving portions of the cycle curve are designed so that they as well as possible to meet the process requirements and still can be performed with the highest possible clock rate. The individual steps of the clock with a high access to verlassigkeit and safety will be performed and it is to a high efficiency, ie high performance of the packaging machine can be achieved. The established format-specific process data is saved. If the blister packaging machine is to process at a later time again blister of the same format, the stored data can be retrieved and operated in accordance with the packaging machine. This approach is the theoretical idea behind that the same blister format with the same stored process parameters can always be optimally processed.

In practice, however, it has shown that it can occur in operation of the blister packaging machine that is part of a larger packaging system, to seeing the problems that the efficiency of the packaging plant can mitigate. These problems may be due to interference from individual stations of the blister packaging machine or in disorders or problems upstream or downstream equipment, for example, in a down- stream cartoner. In the cartoning machine can cause fluctuations in the brochures or the folding box, whereby the preset, relatively high clock rate can not be maintained. Moreover, it can gemaschinen to clock problems folic such come with a bundle packer, or product variations, which are detrimental to the rate of product feed in the blister packaging machine. Moreover, it may be possible that leaves for example for reasons of illness and / or origin^N not enough staff available to the entire packaging line, so that they are reduced in their processing speed uss.

Since the problems and disorders mentioned can not always be solved in the short term or reversed, it is common for the blister packaging machine with either an increased rejection rate or a reduced Verpa^¬ ckungsqualität continue on or if this is not acceptable to stop the machine until the fault has been rectified.

Control technology, it would also be possible to reduce the clock rate of the blister packaging machine and possibly other machines of the packaging line. However, the shape and boiling gelparameter could be greatly changed by this measure that a perfect forming and sealing - process is no longer guaranteed.

The following should be assumed by way of example that the blister packaging machine not with the ur- can be operated originally preset maximum cycle rate R of 75 cycles per minute, for example, because the tablets have changed slightly in their dimensions and thus run more slowly through the supply ducts of the filling station. With undiminished clock speed, the proportion of blisters that are filled incompletely would increase considerably. Problems can also in other machines of the packaging line to make a reduction in the clock rate required.

If the cycle rate R to avoid an increased proportion of incorrectly filled blisters to a different cycle rate R_v is reduced, is obtained for each cycle a higher maximum cycle time T_Max, It is assumed that the cycle rate R of 75 cycles per minute on a modified

Cycle rate R_v is reduced from 50 cycles per minute, so that a new maximum cycle time T_Max = 60,000 / 50 = 1,200 results (ms). In a conventional blister packaging machine the stored cycle curve is maintained in its basic course, but all

Periods T_Vι, T_B, T_v2 and T_R by a factor of 1.200 / 800 = 1.5 renewed. A corresponding extended cycle curve is shown in Fig. 3. It can be seen that the duration T_B treatment, such as a thermoforming and cooling process of soil denfolie is increased by 50%. In addition, at such extended cycle curve, the duration of the 1st and 2nd adjustment are extended, which in turn can lead to shrinking of zugsgeschwindigkeit forward by itself and thus leads to a longer cooling time of the preheated base film during the transportation time. By Λ / hange the process parameters incorrect or incomplete molded cups arise.

The invention has for its object to provide a method for controlling a blister packaging machine, in which the clock rate can be changed within predetermined limits in the production phase, without causing problems during the packaging process and in particular the shapes of the bottom sheet or during the sealing of the cover film.

This object is achieved by a method having the characterizing features of claim 1. It is provided that from the changed cycle rate R_v resulting cycle time difference .DELTA.T substantially to change the duration T_R quiescence is used.

If the cycle rate R to the changed cycle rate R_v is reduced to a time gain respect of the maximum cycle time T results_Max or a cycle time difference .DELTA.T in the example explained above, 400 ms (= 1200 ms - 800 ms). The invention is based on the fundamental idea of ​​this clock time difference T is not uniform on all curves - sections of the cycle curve divide, ie the cycle curve to compress in a known manner or to stretch, but the cycle time difference .DELTA.T substantially or even completely to change the duration T_R to use this computer from sleep. In this way, the essential process can Para^¬ meter, namely the duration of T_Vι the first adjustment, the period T_B treatment of the condition and the duration T_v2 2nd adjustment be kept within narrow limits, which are favorable for the process flow. In a preferred embodiment of the invention, these durations T_Vι, T_B and T_v2 when you enter a different cycle rate R_v un- maintain changed, and thus the cycle time difference .DELTA.T completely to change the duration T_R to use this computer from sleep. At work station whose cycle curve is changed with a change in the clock rate, it may be the forming station of a blister packaging machine. The forming station has a pair of relatively adjustable mold plates, between which a bottom sheet is provided with cup-shaped receptacles. If the base film is made of plastic, it is processed in a pre-heated state and cooled in the forming station. 1. The displacement movement is then GE forms by the closing movement of the mold plates, wherein the closing movement only after reaching the

End position of the mold plates is finished and the mold plates in the final movement of the closing stroke already may be in system. At the end of the closing movement of the mold plates persist over a period spatial T_B in a treatment state where the base film is deformed and optionally cooled. In the second adjustment then it is the opening movement of the mold plates, which go back to their open starting position. Then the mold plates persist over a period T_R in its open position. When the obtained by reducing the clock rate of clock time difference .DELTA.T completely to change the duration T_R Hibernation is used and the temperature of the preheated sheet remains unchanged, thus the actual treatment of the bottom sheet does not change in the Formsta i- on the blister packaging machine and the mold plates are moved to the preset speed. A reduction of the clock rate only causes that the mold plates at the end of the clock for an extended time period to remain in its open position. The constant attitude of the periods T_Vι, T_B and T_v2 leads to the stabilization of the process-relevant size of the molding time. In this way a good deformation of the bottom sheet is provided with high process reliability. Alternatively, it is also possible that the workstation is a sealing station with relatively adjustable sealing plates between which a cover sheet is sealed to the bottom denfolie. In this case, the first adjusting motion is the closing motion of the sealing plates, which at the end of the closing movement over the time period T_B remain in a treatment state in which the sealing of the cover film is carried out on the bottom foil. The second adjusting movement, the opening motion of the sealing plates, the sealing plates after reaching its open position in this for the period T_R remain. In this case, the stabilization of the periods leads T_vι, T_B and T_v2 for constant - pose the process-relevant size of the sealing time.

The desired changed cycle rate R_v (= Cycles per minute) is preferably entered directly through the input device, wherein a processing unit from the inputted changed cycle rate R_v the stationary maximum avail- able cycle time T_Max = 1 / R [min] = 60,000 / R [ms] determined.

In a preferred embodiment of the invention provides that the inputted changed cycle rate R_v not have any value, and in particular can not be excessively small. It is therefore envisaged that a from the preset cycle rate R and the changed cycle rate R_v resulting timing difference .DELTA.R to a limit value .DELTA.R_G is limited. The limit .DELTA.R_G may be in the range of 20% to 30% of the preset cycle rate R and preferably amounts to 25% of the preset cycle rate R.

Further details and features of the invention are apparent from the following description of an embodiment Reference to the accompanying drawing visible. Show it:

Figure 1 is a schematic representation of the essential parts of a blister packaging machine,

2 shows a conventional cycle curve as a path-time -

Diagram in a simplified representation,

3 stretched by a factor of 1.5 cycle curve shown in FIG. 2,

Figure 4 ve an inventively modified Taktkur- and

Figure 5 is a schematic plan view of an input device.

FIG. 1 shows the essential components of a blister packaging machine 10 in a schematic representation. A coming from a stock, composed of plastic base film 11 is firstly a heating station 12 supplied to the heating plate 12b has a lower and an upper heating plate 12 up, which is adjustable relative to the lower heating plate 12b. If the two hot plates 12a and 12b are closed, the bottom foil received between them is heated.

Immediately to the heating station 12 is followed by a

Forming station at 13 which includes a lower mold plate 13a and to adjustable upper mold plate 13b. wherein the video between the two mold plates 13a and 13b, which are shown in the open position, can be closed, the closed mold plates 13a and 13b aufgenomme- ne bottom sheet is cooled and simultaneously provided by supplying compressed air or by means of molding dies with cup-shaped depressions. a transport device 14 adjoins the forming station 13, by means of the ground denfolie 11 intermittently pulled through the individual stations.

The provided with the cup-like depressions bottom sheet 11 is then fed via guide rollers 15 and 16, a filling station 17, in which a product, for example a pharmaceutical tablet is placed in each well. The bottom sheet 11 then passes to a sealing station 20. Immediately prior to the sealing station 20, a cover sheet 18 laid over a guide roller 19 onto the bottom sheet eleventh In the sealing station 20, which includes a lower sealing plate 20b and an upper seal plate 20a, the cover sheet 18 is sealed to the bottom sheet 11 by the warm sealing plates 20a and 20b are closed and acts the heat to the films. The sealing station 20 is followed by a further transport device 21, which in its

Movement is synchronized with the transport device 14 and provides a cyclic transport of the given after the sealing station 20 the composite film.

FIG. 2 shows the above-explained simplified path-time diagram of a cycle curve, for example, the forming station 13. The case assumed maximum cycle time T_Max is 800 ms, which corresponds to a cycle rate R of 75 cycles per minute. Starting from the open basic position of the two molding plates 13a and 13b will close them within a period Tvi, while the production technology specified closing S_v return. Once the mold plates 13a, 13b the end position of its closing movement have reached (point 1 of the curve in Fig. 2), the treatment starts condition that occurs over a period T_B extends. While the treatment state is the base film provided with cup-like depressions. When the bottom sheet is composed of plastic, it is additionally cooled. In point 2 of the curve of the treatment state is finished and it is followed by the opening of the mold plates 13a and 13b, in turn, on the way south_v in reverse direction to the closing movement and for a time T_v2 takes place. At the end of the opening movement of the point 3 of the curve the open starting position of the mold plates is again achieved 13a and 13b, in which it in an idle state for a period T_R remain until the next cycle begins.

In Fig. 2 it was assumed that the further transport of the film in semi-open mold plates 13a and 13b begins and ends, so that a total transport time T_z = Zi + t_z2 results.

If the user finds that this total transport - time T_z is insufficient, it can preset clock rate R decrease. For this purpose, the user enters a reduced clock rate R_v (= Cycles per minute) before, so that the maximum available cycle time T_Max = 60,000 / R_v [Ms] is determined. Assume for example, that the user clock rate R_v sets to 60 cycles per minute, which corresponds to a modified maximum cycle time T_maxv = 1000 ms corresponds.

When a change or reduction in the clock rate of the process parameters for the closing movement of the molding plates are ten retained for the treatment condition for the opening movement of the mold plates, such that the stroke curve between points 1 and 3 does not change as shown in Fig. 4 is shown. However, since the cycle rate R_v to 60 cycles per minute and thus the maximum cycle time T_maxv was increased to 1,000 ms, arises with respect to the origin - loan cycle rate R in the modified, reduced cycle rate R_v a clock time difference T of 200 ms, which is fully associated with the idle state, so that the mold plates for a longer period T_RV remain in its fully open position. As FIG. 4 shows, in this way, the transport time T_zv the films substantially extended, so that the transport speed of the sheets can be adjusted to a value adapted to the foil material.

As Fig. 5 shows the input device 30 is assigned to a processing unit 40 which from the input value for the changed cycle rate R_v the appropriate clock determined curve, and in particular checks whether the entered value of the clock rate is within predetermined limits.