WO2004065220A1

WO2004065220A1 - Method for controlling a blister packaging machine

Info

Publication number: WO2004065220A1
Application number: PCT/EP2004/000379
Authority: WO
Inventors: Richard Christ
Original assignee: Iwk Verpackungstechnik Gmbh
Priority date: 2003-01-23
Filing date: 2004-01-20
Publication date: 2004-08-05
Also published as: MXPA04009093A; BRPI0403926A; JP2006513111A; US20050102977A1; CA2478509A1; EP1517835A1; DE10302726A1

Abstract

The invention relates to a method for controlling a blister packaging machine comprising at least one work station working in a clock-pulsed manner. In a work cycle, at least one first adjusting movement is carried out during a period TV1 followed by a treatment state during a period TB wherein a product and/or material is treated. A second adjusting movement is carried out during a period TV2, followed by a rest state during a period TR. The clock pulse rate R ( pulses/minute) of the packaging machine is inputted by means of the input device. The periods TV1, TB and TV2 can also be directly or indirectly inputted, independently form each other, by means of the input device. A processing unit tests whether the inputted periods TV1, TB and TV2 lie within predefined limits and whether the sum thereof is less than or equal to a maximum clock pulse rate Tmax.

Description

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 work station in which at least a first adjustment movement is carried out over a period of time TVi during a work cycle, a subsequent treatment state in which a treatment of a product and / or material takes place, is taken over a period T _B and then a second adjustment movement is carried out over a period T _v2 , wherein a cycle rate R (= cycles / min) of the packaging machine can be entered by means of an input device.

A blister packaging machine of conventional design comprises a molding station in which a multiplicity of cup-shaped depressions are formed in a base film made of plastic or aluminum, into each of which a product, for example a pharmaceutical tablet, is inserted in a downstream filling station. After the product has been fed in, the base film is fed to a sealing station. A cover film is fed directly in front of or within the sealing station and applied to the base film. sets. The cover film is sealed tightly to the base film by the action of heat within the sealing station, as a result of which the product is enclosed in the cup-shaped depression.

The forming station is operated intermittently and therefore discontinuously. The sealing station can either also be operated intermittently, alternatively it is also known to operate the sealing station continuously, the transition from the intermittent operation of the forming station to the continuous operation of the sealing station taking place via known compensation devices.

The performance of a blister packaging machine essentially depends on the cycle rate R, ie the number of cycles to be carried out per minute. The maximum cycle time T _{max available} in milliseconds to T _max = 60,000 / R [ms] results from the clock rate R, that is to say at a clock rate R of 75 cycles / min the maximum cycle time T _max = 800 ms. A cycle curve of a corresponding work cycle is shown as a simplified, polygon-shaped path-time diagram in FIG. 2a, which will be briefly explained below.

Within the maximum cycle time T _max , for example, the molding station operated in cycles must carry out various movements and processing or treatments. Starting from a basic or zero position at the start of the cycle (point 0 in FIG. 2a), in which two mold plates, between which the base film to be deformed runs completely apart, a first adjustment movement, namely the closing movement of the mold plates, is carried out , The closing path S _v is predetermined in terms of production technology and the closing movement is carried out over a predetermined period of time T _v ι until point 1 (see FIG. 2a) is reached in which the mold plates are closed and have reached their end position.

The mold plates have then reached their treatment state, in which, for example, a preheated plastic base film is cooled over a period T _B , the cup-shaped depressions in the base film also being formed, in particular by means of compressed air or form stamps. In point 2 of the cycle curve, the cooling or treatment of the base film is ended and a second adjustment movement follows, namely the opening movement of the mold plates, which in turn takes place via the path S _v (but in the opposite direction) over a period T _v2 . At the end of the opening movement, ie at point 3 of the cycle curve, the starting position is reached again.

A very short opening time, which is not to be considered further here, which is caused by processing in terms of computer technology or software, or a rest period, which should not be considered further here, can be excluded.

As soon as the mold plates are opened to a sufficient degree, the further transport of the base film can be initiated and carried out. According to FIG. 2a, it is assumed that the further transport of the base film begins when the mold plates have moved apart by the path Sv / 2, ie there is still a time period t _zi and from the beginning of the next for the further transport of the base film until the end of the cycle A period of time t _z2 is available until the time at which the mold plates are half closed again, the total transport time T _z resulting from the sum of t _Z ι and t _z2 . In earlier blister packaging machines, the curves were mechanically determined by rotating cams, the rotation of which was derived from a central, driven main shaft, the so-called vertical shaft. In modern blister packaging machines, the curves are stored in software and the motorized movement of the adjustment movements takes place via servomotors, which are activated by control electronics or the corresponding software. Advantages for the servo drive arise above all if an additional stroke adjustment or a shutdown during operation is required. These functions can be implemented and changed without additional mechanical effort.

When setting up a blister packaging machine, the movement sections of the cycle curve are usually designed in such a way that they meet the process requirements of the customer as well as possible and can still be carried out at the highest possible cycle rate. With this cycle curve, once defined, all products are then driven later during operation of the blister packaging machine.

In practice it often happens that the blister packaging machine cannot be operated at the maximum possible cycle rate of, for example, 75 cycles per minute. This can be due, for example, to the fact that the warm base film is relatively sensitive and that the time T _z available for the further transport of the film (see FIG. 2a) causes such a high film acceleration with maximum warping length that it leads to deformation the slide comes. Problems in other stations of the blister packaging machine, for example in the filling station, can also make it necessary to reduce the clock rate. If the clock rate R is reduced to avoid film deformation, a higher maximum cycle time T _max results for each cycle. It is assumed that the clock rate R is reduced to 50 cycles per minute, so that a maximum cycle time T _max = 60,000 / 50 = 1,200 (ms) results. In the case of a conventional blister packaging machine, the stored cycle curve is retained in its basic course, but all the time periods T _V ι, T _B and T _{v2 are} extended by a factor of 1,200 / 800 = 1.5. This procedure facilitates the control-related coordination of all movements dependent on the movement of the mold plate, for example the movement of the die, the movement of the warp or the movement of the heating plate. A correspondingly stretched clock curve is shown in Fig. 2b. It can be seen from this that the transport time T _z for the film, which results from the sum of the stretched periods t ' _Z ι and t' _z2, is increased by 50%. In this way, more time is available for the film transport, for example, which enables gentle film transport, but the stretching of the working cycle means that the performance of the packaging machine is from 75 cycles per minute to 50 cycles per minute, ie to 50/75 = 66 , 7% reduced.

The invention has for its object to provide a method for controlling a blister packaging machine, which enables the machine fitter to variably adapt the cycle curve or the movement curve to the production and working conditions of the packaging machine.

According to the invention, this object is achieved by a method having the characterizing features of claim 1. It is provided that the time period T _V χ, the time period T _B and the time period T _v2 are entered directly or indirectly independently of one another by means of the input device. ben and that a processing unit is provided, by means of which it is checked whether the entered periods T _V ι, T _B and T _{v2 are} within predetermined limits and whether their sum is less than or equal to a maximum cycle time T _max .

The invention is based on the basic idea of not only compressing or stretching a given curve shape in its entirety, but rather of adapting the individual curve sections to the curve individually and merely checking whether the specified framework conditions are met. In this way, individual curve sections can be individually matched to the prevailing production conditions, so that a higher cycle rate R and thus a higher performance of the packaging machine can be achieved than with conventional compression or expansion of the entire cycle curve.

The work station, whose cycle curve can be changed, can be a molding station of a blister packaging machine. The molding station has two mold plates that can be adjusted relative to one another, between which a base film is provided with cup-shaped receptacles. If the base film is made of plastic, it is processed in a preheated state and cooled in the molding station. The first adjustment movement is then formed by the closing movement of the mold plates, the closing movement only being completed when the mold plates have reached the end position and the mold plates already moving in the last movement phase of the closing movement

Plant can be located. At the end of the closing movement, the mold plates remain in a treatment state over a period of time T _B in which the base film is formed and, if necessary, cooled. Acting in the 2nd adjustment movement then it is the opening movement of the mold plates, which return to their open starting position.

Alternatively, it is also possible for the work station to be a sealing station with sealing plates which can be adjusted relative to one another, between which a cover film is sealed onto the base film. In this case, the first adjustment movement is the closing movement of the sealing plates, which remain in a treatment state at the end of the closing movement over the period T _B , in which the cover film is sealed onto the base film. The 2nd adjustment movement is the opening movement of the sealing plates.

A direct input of time values, in particular in ms, can be provided for the independent input of the time periods T _V1 , T _B and T _v2 . In practice, however, it has proven useful to enter the periods mentioned indirectly by a value for a desired speed v _{sg of} the 1st adjustment movement or the closing movement and a value for a desired speed v _{og of} the 2nd

Adjustment movement or the opening movement is entered. These values are also preferably not entered as absolute values, but as relative values. For this purpose, it is provided that a velocity v _s of the 1st adjustment movement is limited to a maximum speed v _smax and that the desired average Ge ^¬ speed v _sg the first adjusting movement as a percentage

(<100%) is input v _smax the maximum possible speed, from which the processing unit determines at predefined nem adjustment _v s the period T _v ι = s _v / v _sg.

Accordingly, it is provided that the speed V _{0 of} the second adjustment movement is limited to a maximum speed Vo _max and that the desired average Speed V _{og of} the 2nd adjustment movement is entered as a percentage (<100%) of the maximum speed v _omax , from which the processing unit determines the period T _v2 = S _v / V _og for a given adjustment _path .

The duration T _{B of} the treatment state is preferably entered directly as an absolute value in ms using the input device.

The desired cycle rate R (= cycles per minute) is likewise entered directly by means of the input device, the processing unit determining the maximum available cycle time T _max = 1 / R [min] = 60,000 / R [ms] from the entered clock rate R.

Further details and features of the invention are apparent from the following description of an embodiment with reference to the accompanying drawings. Show it:

FIG. 1 shows a schematic illustration of the essential components of a blister packaging machine,

FIG. 2a shows a customary clock curve as a path - time -

Simplified diagram,

2b shows the clock curve stretched by a factor of 1.5 according to FIG. 2a,

FIG. 3 shows the selection options for the period Tvi, FIG. 4 shows the selection options for the period T _B ,

5 shows the selection options for the period T ₂ ,

6 shows a clock curve modified according to the invention and

Figure 7 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 plastic base film 11 coming from a supply is first fed to a heating station 12 which has a lower heating plate 12b and an upper heating plate 12a which is adjustable relative to the lower heating plate 12b. When the two heating plates 12a and 12b are closed, the base film received between them is heated.

Immediately adjacent to the heating station 12 is a molding station 13, which comprises a lower molding plate 13a and an upper molding plate 13b that can be adjusted for this purpose. The two mold plates 13a and 13b, which are shown in the open position, can be closed, the base film received between the closed mold plates 13a and 13b being cooled and simultaneously provided with cup-shaped depressions by supplying compressed air or by means of stamping dies. A transport device 14 connects to the forming station 13, by means of which the base film 11 is pulled through the individual stations in cycles. The bottom film 11 provided with the cup-like depressions is then guided over deflection rollers 15 and 16 of a filling station

17 supplied, in which a product, for example a pharmaceutical tablet, is inserted into each well.

The base film 11 then runs to a sealing station 20. Immediately before the sealing station 20, a cover film 18 is placed on the base film 11 via a deflection roller 19. In the sealing station 20, which comprises a lower sealing plate 20b and an upper sealing plate 20a, the cover film is

18 sealed onto the bottom film 11 by closing the warm sealing plates 20a and 20b and applying the heat to the films. The sealing station 20 is followed by a further transport device 21, which is synchronized in its movement with the transport device 14 and ensures a cyclical transport of the film composite given after the sealing station 20.

FIG. 2a shows the already explained simplified path-time diagram of a cycle curve, for example of the forming station 13. The maximum cycle time T _max assumed here is 800 ms, which corresponds to a cycle rate R of 75 cycles per minute. Starting from the open basic position of the two mold plates 13a and 13b, they are closed within a period of time T _v ι, covering the closing path S _v specified in terms of production technology. Once the mold plates 13a, 13b have reached their end position, the closing movement (point 1 of the curve in Fig. 2a), the treatment condition, extends over a Zeitι ^~ aum T _B begins. During the treatment state, the bottom film is provided with cup-like depressions. If the base film is made of plastic, it is additionally cooled. At point 2 of the curve, the treatment state has ended and the opening of the mold plates 13a and 13b follows, which in turn follows the path S _v in the opposite direction Closing movement and takes place over a period T _v2 . At the end of the opening movement in point 3 of the curve, the starting position is reached again.

In Fig. 2a it was assumed that the further transport of the film begins or ends with half-opened mold plates 13a and 13b, so that a total transport time T _z = tzi + t _z2 results.

If the user determines that this total transport time T _{z is} not sufficient, he can redefine the cycle curve. First of all, the user will check whether he can shorten the duration T _{B of} the treatment state while maintaining the current clock rate R. In addition, the closing speed v _s can possibly be increased, which leads to a shortening of the time period T _V ι. Additionally or alternatively, it can be provided to increase the opening speed v ₀ , which leads to a shortening of the time period T _v2 . If one of these changes is possible without violating production or machine specifications, the user gains time which he can use to extend the total transport time T _{z of} the film.

If the periods T _V ι, T _B , T _v2 cannot be changed or cannot be changed to a sufficient degree, the user will reduce the clock rate R. For this purpose, the user enters a vermin-made ^¬ cycle rate R at the moment (= cycles per minute), so that the maximum available cycle time T _raax = 60,000 / R [ms] is determined. It is assumed by way of example that the user reduces the clock rate R to 60 cycles per minute, which corresponds to a changed maximum clock time T _max = 1,000 ms. The user can then use the input device shown in FIG. 7 to determine a changed closing speed of the mold plates 13a and 13b. For the closing motion a maximum speed V _Smax is predetermined what _v at a fixed closing distance S of a minimum amount of time _v ι _m i _n. Furthermore, a minimum value is specified for the closing speed, which corresponds to a maximum time period Tvi _max , as shown in FIG. 3. The user has the choice of selecting any value within these limits.

The closing movement of the mold plates should preferably be carried out as quickly as possible. If no problems have occurred during the closing movement, the user will select the same closing speed as in the originally specified cycle curve according to FIG. 2a. The selection of the closing speed is entered with the input device 30 according to FIG. 7 as a percentage of the maximum closing speed V _Smax , ie 100% in the present exemplary embodiment.

The opening movement of the mold plates can also be changed by the user within predetermined limits in accordance with the closing movement. These limits are determined by a predetermined maximum opening _speed V _omax , which corresponds to a minimum opening time Tv ₂ i _n for a predetermined opening _path S _{v, and} a minimum opening speed V _om i _n , which corresponds to a maximum opening time _V 2max. Between these two limits, the user has the choice of a large number of opening curves, as indicated in FIG. 5. For the opening movement, the user also _enters the desired opening _speed as a percentage of the maximum opening _speed V _omax . It is assumed that the maximum opening speed V _{omax is} selected, which corresponds to an entry of "100%".

The duration of the treatment state, ie the period T _B in which the two mold plates are closed and the film is formed (molding station) or sealed (sealing station), can be specified by the user on the input device 30 as an absolute value in ms. According to FIG. 4, he has the choice within predetermined limits, ie between a minimum cooling time T _Bm j. _n and a maximum time T _Bmax . The user will choose the duration of the treatment state in accordance with the material-specific requirements of the base film in such a way that good treatment of the base film, for example by cooling and molding in the molding station 13, is reliably ensured. In the exemplary embodiment shown, it is assumed that it takes over the duration of the treatment state from the original cycle curve according to FIG. 2a.

Since the user has chosen the same movement curve as in the starting situation according to FIG. 2a, but has reduced the clock rate to 60 cycles per minute and thus increased the cycle time to 1,000 ms, 200 ms are still available within one work cycle if the opening movement has ended and the mold plates are open again. The user can either use this 200 ms for the

Use transport of the base film, as shown in FIG. 6, but it can also provide to use at least part of this time gained to increase the duration of the treatment state T _B.

As FIG. 6 shows, the user-dependent determination of the cycle curve within predetermined limits makes it possible to provide longer periods of time for the film transport and / or the duration of the treatment period without doing so slow down the closing or opening movement of the mold plates.

As shown in FIG. 7, the input device 30 is assigned a processing unit 40 which determines the corresponding clock curve from the entered values and in particular checks whether the entered values of the clock curve lie within the predetermined limits and whether the clock curve overall is less than or equal to that Cycle time T _max is. It is checked whether the sum of the periods T _V ι, T _B , T _V 2 is less than or equal to the cycle time T _max .

Claims

claims

1. Method for controlling a blister packaging machine, which has a work station that operates at least in cycles, in which at least a first adjustment movement is carried out over a period of time T _V ι during a work cycle, a subsequent treatment state in which a product is treated and / or material takes place, is taken over a period T _B , and then a second adjustment movement is carried out over a period T _v2 , one

Cycle rate R (= cycles / min) of the packaging machine can be input using an input device (30), characterized in that the time period T _v _, the time period T _B and the time period T _{v2 are} each directly or indirectly independent of one another by means of the input device (30) are entered and that a processing unit (40) is provided, by means of which it is checked whether the entered periods T _V ι, T _B , T _v2 lie within predetermined limits and whether their sum is less than or equal to a maximum cycle time T _max .

2. The method according to claim 1, characterized in that the work station is a molding station (13) with mold plates (13a, 13b) which can be adjusted relative to one another, between which a base film (11) is provided with cup-like receptacles.

3. The method according to claim 2, characterized in that the 1st adjustment movement is the closing movement of the mold plates (13a, 13b), that the bottom film (13) is provided with the cup-like depressions in the treatment state, and that the 2nd adjustment movement is the opening movement the mold plates (13a, 13b).

4. The method according to any one of claims 1 to 3, characterized in that the work station a seal -

Station (20) with sealing plates (20a, 20b) which can be adjusted relative to one another, between which a cover film (18) is sealed onto the base film (11).

5. The method according to claim 4, characterized in that the first adjustment movement is the closing movement of the sealing plates (20a, 20b), that during the treatment state the cover film (18) is sealed onto the base film (11) and that the second adjustment movement - The opening movement of the sealing plates (20a, 20b).

6. The method according to any one of claims 1 to 5, characterized in that a speed v _{s of} the 1st adjustment movement is limited to a maximum speed v _sma> and that a desired speed v _{sg of} the 1st adjustment movement as a percentage (<100%) the maximum speed v _{smax is} entered, from which the processing unit (40) at a predetermined Adjustment path s _{v determines} the period T _V ι = s _v / v _sg .

7. The method according to any one of claims 1 to 6, characterized in that a speed v _{Q of} the 2nd adjustment _{movement is} limited to a maximum speed v _omax and that a desired speed v _og the 2nd adjustment movement as a percentage (<100%) of maximum speed is inputted v _omax, from which the processing unit (40) for a given adjustment period T s _v to _v2 = s _v / v _og determined.

8. The method according to any one of claims 1 to 7, characterized in that the period T _{B is entered} directly by means of the input device (30).

9. The method according to any one of claims 1 to 8, characterized in that the desired clock rate R (= clocks per min) is entered directly by means of the input device (30) and that the processing unit (40) the maximum cycle time T _max = 1 / R [min] = 60,000 / R [ms] determined.