WO2006136486A1

WO2006136486A1 - Device and method for producing blister packaging

Info

Publication number: WO2006136486A1
Application number: PCT/EP2006/062760
Authority: WO
Inventors: Manfred Reichert; Heinrich Loecht
Original assignee: Robert Bosch Gmbh
Priority date: 2005-06-20
Filing date: 2006-05-31
Publication date: 2006-12-28
Also published as: DE102005028371A1

Abstract

The invention relates to a device and a method for producing blister packaging. The device consists of a die (1) and a pressure generation unit, which pressurises a liquid, allowing only the latter to make an impression in a foil (6) to be formed, thus moulding the foil (6) in the die (1).

Description

.0 Device and method for producing blister packs

State of the art

The present invention relates to an apparatus and a method for the production of

.5 blister packs according to the preamble of the independent claims. A

Device according to the preamble of the independent claims is already known from DE 28 258 21 Al. A metal-plastic composite film is pre-stretched in a first process step and then formed in a second process step. The Vorstreckung the metal-plastic composite film is under

! 0 Application of pressure by means of a gaseous or liquid medium. For the shaping of the film taking place after pre-stretching, an upwardly and downwardly movable matrix bottom is provided. The further shaping of the pre-stretched film is carried out with the aid of a forming punch. The shape of the punch determines the shape of the cup to be formed.

! 5

For the production of a certain drawing depth, a relatively large output surface of the flat film is required in each case. Due to the process and film only Napfwände with relatively flat side wall angle are possible. There is an annular gap between the submerged molding die and the ring surface of hold-down or

S 0 template. If the tool is not manufactured absolutely precisely or if the annular gap is not the same size everywhere over the circumference, there is a risk of uneven rotation until cracks form. Due to the process, a contact or friction arises between the dipping punch and the inside of the foil. If the two friction parameters - stamp surface to film surface - not exactly matched, it can here also come to unwanted voltage gradients up to the formation of cracks.

Advantages of the invention

5

The device according to the invention and the method according to the invention for the production of blister packs with the characterizing features of the independent claims have the advantage that the process reliability is increased since there is no longer any contact between the film and the forming punch. A use

.0 a smaller base area is made possible by the proposed invention.

In an expedient development it is provided that the pressure-generating device pressurizes the liquid with a pressure of approximately 100 bar .5. As a result, on the one hand, a secure deformation of the film, on the other hand

Risk of cracking minimized.

In an expedient development, a drying device is provided. The use of liquid for molding in conjunction with a

! 0 drying device could now also the cleaning process for the film in the

Integrate forming process.

In an expedient development, a return flow system is provided which can compensate for the fluid loss. As a result, the fluid loss of! 5 forming process minimized.

In an expedient embodiment, an overflow channel is provided for receiving the outflowing liquid volumes after opening the mold device.

S 0 Further expedient developments emerge from other dependent

Claims and from the description.

drawing Embodiments of the invention are illustrated in the drawings and are explained in more detail below. 1 shows a first embodiment of the device for producing blister packs in a perspective cross-section with electromechanically accelerated membrane, Figure 2 shows a second embodiment in which the hydraulic pressure wave is generated by a hydraulic unit.

Description of the embodiment

.0 A film 6 is fed to a shaping device 20. A molded film piece 8, which has shaped cups 7, leaves the forming device 20. The film 6 to be formed is clamped between a die 1 and a mold base 2. die

1 is separated by the film 6 from a liquid storage 5, in which liquid is not shown. By means of a flat coil 3 electromechanical

.5 accelerated membrane 4, which is located below the liquid storage 5, a hydraulic pressure wave is generated in pulses, which is used for forming the film 6. Alternatively to the membrane 4, a piston can also be used. In the die 1 are provided at the points where the film 6 is deformed, correspondingly formed vent holes 9, so that the air at these points

! 0 can escape. At the side of the mold base which is in contact with the film 6

2, an overflow channel 13 is provided in the form of a rectangular recess. The overflow channel 13 is designed such that the liquid can run back through a return line 14 into a liquid collecting container 15. Lost liquid is supplied via a micro-metering pump 10. A check valve 11 prevents

! 5 while running back the liquid. Via a pressure line 12, liquid can

Liquid storage 5 are supplied. After the film 6 leaves the former 20, it is passed over the opening of the return line 14. This is followed by a suction device 16, in order to remove possibly still adhering liquid. Subsequently, the deformed piece of film 8 in a drying device 17th

S 0, for example, dried by means of warm air 18.

In the embodiment according to FIG. 2, the molding unit 20 is supplied in a pulsed manner with liquid 24 via a valve 24, which provides a conventional hydraulic unit 22 with associated container 23.

S5 - A -

The devices described work as follows: The film 6 is fed to the former 20. As foils 6, for example, aluminum-plastic composites are used, for example in a three-layered construction plastic aluminum-plastic. A typical example of this is PVC (60 μm

5 inside) aluminum (45 μm) and OPA (25 μm outside). But there are also other film thicknesses, both the individual layers as well as the overall composite as well as other plastic materials such as PE or PP into consideration. According to the invention can now be dispensed with the use of punches. For the pressure generating device consisting of flat coil 3, 4 and membrane

.0 liquid storage 5 generates a pressure pulse advantageously the

Order of magnitude of 100 bar. By this pressure pulse, the film 6 is completely pressed into the formations of the die 1. The starting surface or depth of the shaped cup 7 depends on the dimensions of the product to be filled, such as tablets, capsules and the like. Also the number of

.5 applied cups 7 and thus the shape of the die 1 varies depending on

Application. Die 1 and mold base 2 are movable relative to each other. The film 6 is clocked fed to the molding device 20. If the piece of film to be formed is in position, the film 6 is pressure-tightly clamped between the die 1 and the lower mold part 2. The die 1 is, as in the

! 0 drawing shown, formed as a negative mold of one or more blisters. According to the illustrated embodiment, the flat coil 3 electromechanically accelerates the membrane 4, which is located below the liquid storage 5, so that a pulse-like hydraulic pressure wave is generated, which is used for forming the film 6. By the pressure wave, the film 6 in each case at the points where the

! 5 recesses of the die 1 and the predetermined shape are, to the respective

Cup 7 deformed. Thus, a molded film piece 8 is formed per molding process. The deformation of the film 6 relative to the cups 7 thus takes place from bottom to top. In the die 1 must be ensured at the points where the film 6 is deformed by appropriately trained vent holes 9 that the air at these points

\ 0 can escape. As with this principle, the pressure fluid with both the flat film

(between the cups) as well as with the deformed cups 7 comes into contact, takes place here at the same time a cleaning of the film surface. It has been found helpful for the process optimization to bias the membrane 4 already by a slight static deflection, before the actual pressure wave

S 5 is generated. In the course of production inevitably remains a small proportion Hang liquid on the cups 7 or on the film 6. Therefore, a regulation of the liquid level is necessary. Lost liquid is fed back through the microdosing pump 10. For this purpose, the liquid of the liquid reservoir 5 is pumped to the overflow via the pressure line 12. The overflowing 5 liquid is collected in the overflow channel 13 and back into the liquid storage

5 returned. The overflow channel 13 is designed so that the liquid can run back through the return line 14 into the water collection tank 15.

After completion of the molding die 1 is lifted from the mold base 2. The .0 deformed piece of film 8 is transported to the next station. Here, the possibly still adhering liquid is removed by means of a suction device 16. The suction device 16 can be supplied to the water collecting tank 15. Subsequently, the deformed film piece 8 is dried in the drying device 17, for example by means of warm air 18. As a liquid, for example .5 Water could be used.

The described Druckimpulserzeugung could also be made in other ways than on electro-hydraulic. It would, for example, to think of a hydraulic unit 22, as shown by way of example in Figure 2, the! 0 pressure pulse via a conventional valve 24 is to generate. For this purpose, for example, a proportional valve would be suitable. The desired control characteristics can thus be easily realized, which take into account the desired pressure build-up.

Since at least the bottom of the film 6 in the liquid storage 5 with the liquid! 5 comes into contact, the liquid can also be used to clean the film 6. In particular, the application of a pressure pulse improves the cleaning behavior. It could also germ-free liquid, generated for example by means of ultrasound, further support the cleaning function.

Claims

03.06.2005 Lc / Zj 5ROBERT BOSCH GMBH, 70442 Stuttgart.0 Claims

1. An apparatus for producing blister packs, comprising at least one die (1), with at least one pressure generating means (3, 4, 5) which acts on a liquid with pressure .5, characterized in that only the liquid to be formed a film

(6) presses into the die (1) for forming the film (6) in the die (1).

2. Apparatus according to claim 1, characterized in that the pressure generating means (3, 4, 5) generates a pressure pulse of about 100 bar.

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3. Device according to one of the preceding claims, characterized in that at least flat coil (3) and diaphragm or piston (4) and / or a hydraulic unit with associated valve are used as pressure generating means.

! 5 4. Device according to one of the preceding claims, characterized in that a liquid collecting container (15) is provided for feeding the liquid reservoir (5).

5. Device according to one of the preceding claims, characterized in that S 0 collecting means (14) are provided for catching still on the film (6) befindlicher

Liquid.

6. Device according to one of the preceding claims, characterized in that as a collecting means reflux line (14) and / or suction device (16) is provided

S 5 are.

7. Device according to one of the preceding claims, characterized in that means (10, 11, 12, 15) for regulating the liquid level of the liquid reservoir (5) are provided.

5

8. Device according to one of the preceding claims, characterized in that overflow means (13) are provided for collecting the liquid which overflows from the liquid reservoir (5).

9. Device according to one of the preceding claims, characterized in that a drying device (17) is provided for drying the film (6).

10. A process for the production of blister packs, wherein in a first step, film (6) between a die (1) and a lower mold part (2) is brought in one

.5 second step foil between the die (1) and mold base (2) is clamped, in a third step with the film (6) in connection standing liquid is acted upon by a pressure pulse, characterized in that only the pressure pulse of the liquid to be formed Foil (6) in the die (1) presses to the formation of the film (6) in the die (1).

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