EP3102503B1 - Cartridge and method for producing a cartridge - Google Patents

Description

The present invention relates to a cartridge according to the preamble of claim 1 or 2. Furthermore, the invention is directed to a method for manufacturing and in particular in addition to filling such a cartridge. In the industrial sector, in the construction industry, for example of buildings, and also in the dental field cartridges are often used to store liquid flowable, often pasty or viscous to highly viscous substances and carry out as needed for each application. Examples of such substances are joint sealants, compounds for chemical dowels or chemical anchors, adhesives, pastes or molding compounds in the dental field. Usually, these cartridges are made of plastic and are produced in an injection molding process.

A distinction is made between one-component systems in which the material to be discharged consists of only one component, and two-component or multi-component systems in which at least two different components are stored in separate chambers of the same cartridge or in separate cartridges, the components being discharged by means of a dynamic or a static mixing device are intimately mixed. Examples include two-component adhesive or chemical dowels that cure only after mixing the two components. Especially in the industrial sector, two-component systems are also used for paints, which are often used for the production of functional protective layers, for example for corrosion protection.

It is often the case that the cartridges comprise one (or more) axially displaceable delivery pistons, by the movement of which the material is discharged from the chamber or the chambers. It is understood that for this purpose the chambers must have sufficiently thick walls in order to withstand the pressure arising during discharge can. In addition, the cartridges must have sufficiently thick walls to be sufficiently diffusion-tight. This is particularly important with regard to storage, in order to effectively prevent the inward diffusion or outward diffusion of the chemical substances and thus a degradation of the cartridge contents. Since such plastic cartridges are usually designed for single use, resulting from both the volume and the mass of a considerable amount of waste, which is particularly disadvantageous from aspects of environmental protection.

A known alternative to the plastic cartridges are hoses in which the respective materials are stored. These hoses are then placed in special support or discharge devices to discharge their contents for the particular application. Although such hoses are significantly cheaper than cartridges, especially as regards the volume of waste, they have other disadvantages. It requires much more complex filling devices to fill the hoses and close. In addition, their storage is more problematic because hoses are not stable, so special measures or packaging must be provided for storage. There may also be problems with the tightness of such hoses. In addition, the mass of the residual volume in the hose, which can not be discharged, is relatively high. Hoses also have the disadvantage that they are very sensitive to mechanical influences, especially against sharp edges or sharp corners.

In addition to the aspect of environmental protection, the issue of sustainability is also becoming increasingly important. The use of renewable raw materials, The minimization of raw material and energy consumption and the greatest possible reduction of waste, both with regard to the cartridge per se and to the remaining volume in the cartridge, are becoming increasingly important.

The unfilled cartridges are usually transported by the cartridge manufacturers to the manufacturers of filling materials (media) who then take care of filling the empty cartridges. Even if the unfilled cartridges have a relatively low weight, the costs for transporting the empty cartridges from the cartridge manufacturers to the media manufacturers are relatively high, since the empty cartridges have a relatively large volume and thus a high space requirement during transport. In addition, the storage costs for the empty cartridges are relatively high for both the cartridge manufacturers and the media manufacturers due to the space required. These costs account for a not inconsiderable part of the total manufacturing costs of the cartridges.

From the EP 0 992 438 A1 a cartridge according to the preamble of claims 1 and 2 is known. In order to empty the entire air contained in the empty cartridge before filling the cartridge, it is first brought into a collapsed state. For this purpose, the rear half of the flexible cartridge wall is invaginated into the front half of the cartridge and then any residual air contained removed by applying a vacuum. The cartridge or receiving chamber which has been screwed together in this way has approximately 50% of the space required by the cartridge or the receiving chamber in the expanded state. Subsequently, the cartridge is filled with the desired material and the filled cartridge stored or delivered in the usual way.

It is an object of the invention to provide a cartridge of the type mentioned above and a method for producing such a cartridge, with which the total manufacturing costs can be reduced.

According to the invention this object is achieved with a cartridge having the features of claim 1 or 2 and with a method for producing such a cartridge with the features of claim 7, 14 or 15.

With the invention, the space requirement of a not yet filled cartridge, depending on the maximum filling volume of the cartridge, to a fraction, namely less than 30%, in particular less than 25%, preferably less than 20% of the space requirement of a conventional cartridge or the cartridge be reduced in the expanded state. Likewise, the space requirement of a not yet filled receiving chamber, depending on the maximum filling volume of the receiving chamber, to a fraction, namely less than 30%, in particular less than 25%, preferably less than 20% of the space required by the receiving chamber in the expanded state. According to the invention, the knowledge is exploited that the flexible cartridge wall of a collapsing cartridge can be pushed together not only when discharging the filling material from the filled cartridge, but also that a cartridge which has not even been filled can be collapsed in a corresponding manner. Thus, at the same time the volume of the cartridge or its receiving chamber can be minimized, so that the storage and transport costs can be significantly reduced due to the reduced space requirement. Since the collapsed cartridge can easily be returned to its expanded state at any time, the expansion and the associated increase in the volume of the receiving space are only required when the cartridge is filled with the filling material. Under the space required by the cartridge / receiving chamber is not the internal volume of the cartridge / receiving chamber to understand, but the volume of the cartridge / receiving chamber enclosing virtual envelope (convex hull) or the cartridge / receiving chamber enclosing space for storage and / or the transport of the cartridge / receiving chamber is needed.

The connection between the head part and the cartridge wall can be realized for example by gluing, fusing, welding or by jamming. It is also possible that the head part is molded onto the cartridge wall, in particular at its front end, and thus the head part and the cartridge wall are integrally formed. The end remote from the head part of the cartridge wall is formed closed to form the receiving chamber. In this case, the closed end can be generated directly during the production of the film tube. But it is also possible that this end is initially formed open and is subsequently closed in a further process step. This can be done for example by gluing, crimping, fusing, welding, by clamping, for example by means of a clamping ring or by attaching a separate end element such as an end plate.

The design of the cartridge wall as a film on the one hand means a considerable reduction of the waste and the raw materials required for the production and on the other hand brings with it a very high flexibility with regard to the choice of material. Depending on the application, the film can be adapted to the specific cartridge content and at the same time represents a very efficient diffusion barrier. Preferably, the cartridge according to the invention can be inserted into a reusable support cartridge during filling and / or discharging its contents. Preferably, the film forming the cartridge wall can be designed as a multilayer system, in particular as a composite film. The film may comprise plastic layers and / or metallic layers, in particular one or more aluminum layers.

According to a preferred embodiment of the invention, in the collapsed state of the cartridge, the cartridge wall is pushed together in the longitudinal direction of the receiving chamber. As a result, a shortening of the cartridge is automatically achieved, which corresponds to an optimal reduction in space requirements. About that In addition, the pushing together in the longitudinal direction corresponds to the pushing together of the cartridge wall when discharging the filling compound, so that the cartridge wall does not have to be specially set up in order to allow the pushing together of the unfilled cartridge. In principle, it is also conceivable that the cartridge wall is converted in another way to achieve the collapsed state. For example, the cartridge wall could be deformed transversely and in particular perpendicular to the longitudinal axis of the receiving chamber and in particular pushed together. This could be achieved, for example, by creating a negative pressure or a vacuum in the unfilled receiving space, through which a contraction of the cartridge wall takes place transversely to the longitudinal direction of the receiving chamber. Subsequently, the thus flattened cartridge wall could, for example, be rolled up or folded in order to achieve a length reduction of the cartridge.

The cartridge is preferably designed as a one-component cartridge with a receiving chamber or as a multi-component cartridge with a plurality of receiving chambers, in particular as a two-component cartridge with two receiving chambers. In particular, the receiving chambers may have a cylindrical shape and, in the case of a multi-component cartridge, be arranged next to one another. It is also possible that the receiving chambers have a different shape from the cylindrical shape and in particular are formed so that they side by side together give a cylindrical shape.

In the case of a multi-component cartridge, each receiving chamber is preferably assigned a separate head part, the outlet of which is in fluid communication with the receiving chamber assigned to it. However, it is also possible that the receiving chambers is associated with a common common head part, wherein the head part has a plurality of outlets, one of which is in fluid communication with a respective receiving chamber.

Preferably, the head part is molded onto the cartridge wall. As a result, a one-piece design and thus a very dense and stable connection of the headboard and cartridge wall is achieved. Advantageously, the end of the cartridge wall remote from the head part is sealingly closed by a crimping or clamping connection. The originally open end of the tubular cartridge wall can be sealed in this way simple, inexpensive and reliable.

In the method according to the invention, at first the cartridge wall is sealingly and non-detachably connected to the head part in such a way that the cartridge is produced in its expanded state. Only after generating the cartridge in its expanded state, the cartridge wall is pushed together so that the cartridge is transferred to its collapsed state in which the receiving chamber has its minimum volume. This is completely contrary to the previously known procedures for producing a cartridge, in which the empty cartridge is always generated with its maximum filling volume. It was only within the scope of the present invention that it was recognized that producing the empty cartridges in the collapsed state can result in considerable cost savings during storage and transport, and that, nevertheless, the maximum filling volume for the filled cartridge can be produced without problem by the cartridge being inserted just before the cartridge Filling or during and in particular directly brought by the filling of its collapsed state in the expanded state.

According to a preferred embodiment of the invention, the end of the cartridge wall remote from the head part is sealingly closed prior to pushing together. This can for example be done directly in the manufacture of the tubular cartridge wall by one end of the cartridge wall is made closed. But it is also possible that the cartridge wall is first produced with two open ends and only at a later time, the remote from the headboard end is closed, as has already been stated above.

Advantageously, the cartridge wall is pushed together in the longitudinal direction of the receiving chamber. In particular, it is preferred that a predefined pressure is generated in the receiving chamber and the pushing together of the cartridge wall takes place against the pressure. More preferably, when pushed together, the pressure is reduced gradually and the pressure chosen in particular so high that the cartridge wall when pushed together is folded like a concertina in essence. This ensures a controlled pushing together of the cartridge wall, which in turn allows easy sliding apart of the cartridge wall during filling. As already described, it is basically also conceivable that the cartridge wall is converted in another way to achieve the collapsed state. For example, the cartridge wall could be deformed transversely and in particular perpendicular to the longitudinal axis of the receiving chamber and in particular pushed together.

More preferably, the medium is filled through the outlet in the head part into the receiving chamber for filling the cartridge. This ensures that the receiving chamber is reliably filled, especially in the area of the outlet with medium.

Advantageously, the cartridge wall is pushed apart again by filling the cartridge so that the cartridge is transferred from its collapsed state into a partially expanded state or into its expanded state. Thus, for the expansion of the cartridge no separate process step is required, since expanding and filling are realized in a common process step.

Fig.1

eine erfindungsgemässe Zweikomponentenkartusche in ihrem expandierten Zustand,

Fig. 2

die Kartusche nach Fig.1 in ihrem kollabierten Zustand,

Fig. 3

eine erfindungsgemässe Kartusche ohne Verschlusskappe,

Fig. 4

eine geöffnete Austragvorrichtung für eine erfindungsgemässe Kartusche ohne eingesetzte Kartusche,

Fig. 5

die Austragvorrichtung nach Fig. 4 mit teilweise eingesetzter Kartusche nach Fig. 3,

Fig. 6

die Austragvorrichtung nach den Fig. 4 und 5 mit vollständig eingesetzter, austragsbereiter Kartusche und

Fig. 7

ein schematisches Flussdiagramm der Herstellung und der Verwendung einer erfindungsgemässen Kartusche.

The invention will be described in more detail below with reference to an embodiment with reference to the drawings; in these show:

Fig.1

a two-component cartridge according to the invention in its expanded state,

Fig. 2

the cartridge after Fig.1 in her collapsed state,

Fig. 3

an inventive cartridge without cap,

Fig. 4

an open discharge device for a cartridge according to the invention without inserted cartridge,

Fig. 5

the discharge after Fig. 4 with partially inserted cartridge after Fig. 3 .

Fig. 6

the discharge after the 4 and 5 with fully inserted, ready for use cartridge and

Fig. 7

a schematic flow diagram of the production and use of a cartridge according to the invention.

Fig. 1 shows a designed as a two-component cartridge cartridge 1, which comprises two cylindrical receiving chambers 2, 3. The receiving chambers 2, 3 are bounded in each case by a cartridge wall 4, 5 as well as by a common head part 6, which respectively forms an end-side end of each receiving chamber 2, 3. The two ends 7, 8 of the two cartridge walls 4, 5 which are remote from the head part 6 are in each case to the central axis of the respective receiving chamber 2, 3 brought together and bound together by a respective clamping ring 9, 10 so that the ends 7, 8 are sealed sealing.

The head part 6 facing ends 11, 12 are sealingly and permanently connected to the head part 6 by the head part 6 is molded onto the ends 11, 12. While the head part 6 consists of a dimensionally stable plastic, the cartridge walls 4, 5 are designed as a multilayer film, which are rolled and welded in their predominant central region to a cylindrical shape and form together with the head part 6, the cylindrical receiving chambers 2, 3.

The head part 6 has two outlets 13, 14, which are connected for filling the receiving chambers 2, 3 with filling material and for discharging the filling material from the receiving chambers 2, 3 with these. Furthermore, a screw cap 15 is provided, through which the outlets 13, 14 are closed together.

In Fig. 1 are the receiving chambers 2, 3 is not filled with filling material, ie the medium to be discharged, but empty. Nevertheless, the cartridge walls 4, 5, due to the rigidity of the film material used in the Fig. 1 shown substantially cylindrical shape, which represents the expanded state of the cartridge 1 with maximum volume of the receiving chambers 2, 3.

According to the invention, the cartridge walls 4, 5 are pushed together before being filled with the medium to be discharged in the longitudinal direction of the receiving chambers 2, 3 until the cartridge is in its collapsed state in which the receiving chambers 2, 3 each have their minimum volume occupies. This collapsed state is in Fig. 2 shown. From the comparison of Fig. 1 and 2 becomes immediately clear that the space requirement of the cartridge 1 and the receiving chambers 2, 3 in the collapsed state is only about 20% of the space required in the expanded state. The pushing together of the cartridge walls 4, 5 can, in particular when screw cap 15 is unscrewed by a discharge device described in more detail below.

Fig. 3 shows one opposite the Fig. 1 and 2 slightly modified cartridge 1. The only difference is that in the region of the outlets 13, 14 no screw connection for fastening the screw cap 15, but a bayonet connection for attaching a cap with bayonet closure is provided. The design of the fastening by screwing or by a bayonet connection is not relevant to the present invention. In addition, a bayonet attachment in addition to a plugging movement includes an adjoining rotational or screwing, so that in the following for simplicity uniformly the terms "screw" or "Schraubansatz" are used, even if a bayonet attachment of the cap is shown. In Fig. 3 can be seen due to the removed screw cap 15 that the outlets 13, 14 extend to a frontal free end of a screw 16, to which the screw cap 15 can be screwed. About the outlets 13, 14 is a front filling of the cartridge located in its collapsed state 1 is possible, with the cartridge filled by 1 automatically in their in Fig. 3 shown expanded state is transferred.

Fig. 4 shows a discharge device 17, in which the cartridge 1 according to the invention can be used. The discharge device 17 comprises a two-component support cartridge 18, on whose front side two receiving openings 19, 20 are formed for the cartridge 1. As in Fig. 5 the cartridge 1 with its cartridge walls 4, 5 can be pushed into the receiving openings until the head part 6 bears against the end face of the support cartridge 18.

Subsequently, the support cartridge 18 can be pivoted together with the inserted cartridge 1 about a pivot axis 21, so that they are inside a housing portion 22 of the discharge 17 comes to rest, as it is in Fig. 6 is shown. The screw lug 16 protrudes through an end opening 23 in the housing portion 22, so that for discharging the present in the receiving chambers 2, 3 medium, a mixer tip, not shown, can be screwed onto the screw boss 16. Subsequently, in a conventional manner by repeated actuation of an actuating lever 24, a ratchet slide 25, at the front end of two plate-shaped feed piston 26, 27 are provided, are displaced in the direction of the front end of the discharge 17, whereby in the receiving chambers 2, 3rd existing filling material discharged through the outlets 13, 14 and then mixed by the mixer tip.

Out Fig. 7 is indicated in a step 1 "production" that can be significantly saved by the design of the cartridge wall as a film manufacturing costs compared to a cartridge with dimensionally stable cartridge wall. By transferring the empty cartridge directly after its production in its collapsed state, the space required in step 2 "storage (empty)" is reduced by about 80%, whereby the storage costs are reduced accordingly. Similarly, when transporting the empty, collapsed cartridges to the media manufacturers about 80% in volume and weight saved, as it is indicated in step 3 "Transport (empty)". Only during the subsequent filling of the cartridges (step 4 "filling") the cartridges are expanded again, so that in the subsequent transport (step 5 "transport (filled)") only a 15% weight reduction due to the film used is given. The subsequent steps 6 "storage (filled)" and 7 "application" then take place in a known manner, while in step 8 "waste disposal" again there is an approximately 80% volume reduction compared to cartridges with dimensionally stable cartridge wall.

LIST OF REFERENCE NUMBERS

1

cartridge

2

receiving chamber

3

receiving chamber

4

cartridge wall

5

cartridge wall

6

headboard

7

The End

8th

The End

9

clamping ring

10

clamping ring

11

The End

12

The End

13

outlet

14

outlet

15

screw cap

16

screw attachment

17

discharge

18

Two-component cartridge support

19

receiving opening

20

receiving opening

21

swivel axis

22

housing section

23

opening

24

actuating lever

25

ratchet slide

26

feed piston

27

feed piston

Claims (15)

1. A cartridge (1) having a reception chamber (2, 3) extending in a longitudinal direction for a medium to be dispensed having a head part (6) and a cartridge wall (4, 5) which bound the reception chamber (2, 3), wherein the head part (6) has an outlet (13, 14) for the medium, the cartridge wall (4, 5) is configured at least regionally as a film and the head part (6) is configured as a stable-shape part and the head part (6) is sealingly and in particular unreleasably connected to the cartridge wall (4, 5), with the cartridge (1) being configured as a collapsible cartridge (1), i.e. with it being able to be converted from an expanded state in which the reception chamber (2, 3) has a maximum volume into a collapsed state in which the reception chamber (3, 4) has a minimal volume;
   and wherein the cartridge (1) not yet filled with medium is in its collapsed state,
   characterized in that
   the space requirements of the not yet filled reception chamber (2, 3) in the collapsed state only amounts to 30% or less, in particular only 25% or less, preferably only 20% or less, of the space requirements of the reception chamber (2, 3) in the expanded state.
2. A cartridge (1) having a reception chamber (2, 3) extending in the longitudinal direction for a medium to be dispensed having a head part (6) and a cartridge wall (4, 5) which bound the reception chamber (2, 3), wherein the head part (6) has an outlet (13, 14) for the medium, the cartridge wall (4, 5) is configured at least regionally as a film and the head part (6) is configured as a stable-shape part and the head part (6) is sealingly and in particular unreleasably connected to the cartridge wall (4, 5), with the cartridge (1) being configured as a collapsible cartridge (1), i.e. with it being able to be converted from an expanded state in which the reception chamber (2, 3) has a maximum volume into a collapsed state in which the reception chamber (3, 4) has a minimal volume;
   and wherein the cartridge (1) not yet filled with medium is in its collapsed state,
   characterized in that
   the space requirements of the not yet filled cartridge (1) in the collapsed state only amounts to 30% or less, in particular only 25% or less, preferably only 20% or less, of the space requirements of the cartridge (1) in the expanded state.
3. A cartridge in accordance with claim 1 or claim 2,
   characterized in that
   the cartridge wall (4, 5) is pushed together, in particular like a concertina, in the longitudinal direction of the reception chamber (2, 3) in the collapsed state of the cartridge (1).
4. A cartridge in accordance with at least one of the preceding claims,
   characterized in that
   the cartridge (1) is configured as a single-component cartridge having a reception chamber or as a multicomponent cartridge having a plurality of reception chambers (2, 3), in particular as a two-component cartridge having two reception chambers (2, 3).
5. A cartridge in accordance with claim 4,
   characterized in that,
   in the case of a multicomponent cartridge, a separate head part is associated with each reception chamber and its outlet is respectively in fluid communication with the reception chamber associated with it;
   or
   in that, in the case of a multicomponent cartridge, a uniform common head part (6) is associated with the reception chambers (2, 3), with the head part (6) having a plurality of outlets (13, 14) of which a respective one is in fluid communication with a respective one reception chamber (2, 3).
6. A cartridge in accordance with at least one of the preceding claims,
   characterized in that
   the head part (6) is injection molded to the cartridge wall (4, 5); and in that the end (7, 8) of the hose-shaped cartridge wall (4, 5) disposed remote from the head part (6) is sealingly closed by a crimp connection or by a clamp connection.
7. A method for manufacturing a cartridge in accordance with at least one of the preceding claims,
   wherein
   the cartridge wall (4, 5) is sealingly and unreleasably connected to the head part (6) for producing the cartridge (1) in its expanded state; and wherein the wall (4, 5) of the not yet filled cartridge is pushed together after the production of the cartridge (1) in its expanded state such that the cartridge (1) is converted into its collapsed state in which the reception chamber (2, 3) has its minimal volume.
8. A method in accordance with claim 7,
   characterized in that
   the cartridge (1) not yet filled with medium is stored and/or is transported to a filling apparatus in its collapsed state.
9. A method in accordance with claim 7 or claim 8,
   characterized in that
   the end (7, 8) of the cartridge wall (4, 5) disposed remote from the head part (6) is sealingly closed before the pushing together.
10. A method in accordance with claim 7, claim 8 or claim 9,
    characterized in that
    the cartridge wall (4, 5) is pushed together in the longitudinal direction of the reception chamber (2, 3).
11. A method in accordance with at least one of the claims 7 to 10, characterized in that
    a predefined pressure is generated in the reception chamber (2, 3) and the pushing together of the cartridge wall (4, 5) takes place against the pressure.
12. A method in accordance with claim 11,
    characterized in that
    the pressure is gradually reduced on the pushing together; and in particular in that the pressure is selected as so high that the cartridge wall (4, 5) is substantially folded together like a concertina on the pushing together.
13. A method in accordance with at least one of the claims 7 to 12,
    characterized in that
    the medium is filled into the reception chamber (2, 3) through the outlet (13, 14) in the head part (6) for filling the cartridge (1); and in particular in that the cartridge wall (4, 5) is pushed apart again by the filling of the cartridge (1) so that the cartridge (1) is converted from its collapsed state into a partly expanded state or into its expanded state.
14. A method for manufacturing a cartridge (1) having a reception chamber (2, 3) extending in the longitudinal direction for a medium to be dispensed having a head part (6) and a cartridge wall (4, 5) which bound the reception chamber (2, 3), wherein the head part (6) has an outlet (13, 14) for the medium, the cartridge wall (4, 5) is configured at least regionally as a film and the head part (6) is configured as a stable-shape part and the head part (6) is sealingly and in particular unreleasably connected to the cartridge wall (4, 5), with the cartridge (1) being configured as a collapsible cartridge (1), i.e. with it being able to be converted from an expanded state in which the reception chamber (2, 3) has a maximum volume into a collapsed state in which the reception chamber (3, 4) has a minimal volume; and wherein the cartridge (1) not yet filled with medium is in its collapsed state, said method in particular for manufacturing a cartridge in accordance with at least one of the claims 1 to 6,
    wherein the cartridge wall (4, 5) is sealingly and unreleasably connected to the head part (6) for producing the cartridge (1) in its expanded state; and wherein the cartridge wall (4, 5) is pushed together after the production of the cartridge (1) in its expanded state such that the cartridge (1) is converted into its collapsed state in which the reception chamber (2, 3) has its minimal volume,
    characterized in that
    the cartridge (1) not yet filled with medium is stored and/or is transported to a filling apparatus in its collapsed state.
15. A method for manufacturing a cartridge (1) having a reception chamber (2, 3) extending in the longitudinal direction for a medium to be dispensed having a head part (6) and a cartridge wall (4, 5) which bound the reception chamber (2, 3), wherein the head part (6) has an outlet (13, 14) for the medium, the cartridge wall (4, 5) is configured at least regionally as a film and the head part (6) is configured as a stable-shape part and the head part (6) is sealingly and in particular unreleasably connected to the cartridge wall (4, 5), with the cartridge (1) being configured as a collapsible cartridge (1), i.e. with it being able to be converted from an expanded state in which the reception chamber (2, 3) has a maximum volume into a collapsed state in which the reception chamber (3, 4) has a minimal volume; and wherein the cartridge (1) not yet filled with medium is in its collapsed state, said method in particular for manufacturing a cartridge in accordance with at least one of the claims 1 to 6,
    wherein the cartridge wall (4, 5) is sealingly and unreleasably connected to the head part (6) for producing the cartridge (1) in its expanded state; and wherein the cartridge wall (4, 5) is pushed together after the production of the cartridge (1) in its expanded state such that the cartridge (1) is converted into its collapsed state in which the reception chamber (2, 3) has its minimal volume,
    wherein a predefined pressure is generated in the reception chamber (2, 3) and the pushing together of the cartridge wall (4, 5) takes place against the pressure,
    characterized in that
    the pressure is gradually reduced on the pushing together.

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