EP3971106B1 - Two component cartridge - Google Patents

Description

The invention relates to a system comprising a two-component cartridge and an inner container. In particular, the invention relates to the structural design and the functionality of the two-component cartridge.

The use of cartridges is known in particular for the application of plastic masses and pasty substances such as silicones, adhesives and the like. The substance is pressed out of the cartridge with the help of a cartridge press. In order to bring about a desired chemical reaction, it may be necessary to mix two substances together. In these cases, these components must be kept separate from each other prior to processing. For reasons of easier handling, it is often desirable to provide both components in a common cartridge.

Such two-component cartridges are known in different versions. For example, show DE 203 16 879 U1 , DE 298 07 938 U1 and U.S. 5,566,860 A Cartridges that can be filled with two components and have separate storage volumes for this purpose. With the known two-component cartridges, however, problems arise in the areas of filling, storage stability and warehousing.

Another disadvantage of the known two-component cartridges is that the ratio in which the components are mixed with one another is fixed by design.

In addition, with the existing two-component cartridges, it is often not possible for the user to determine with certainty whether the two substances actually come out of the cartridge mixed during application. Although the components can be provided with dyes, so that it can be read from a color change whether a mixture has taken place. This is particularly possible when one component is colored white and the other component is colored black, resulting in a gray coloration of the mixed product. However, if both components have similar colors, for example because a corresponding coloring of the components is not possible or because the mixed product has a must have a specific colour, the quality of the mixture is difficult to check on the basis of the color of the mixed product.

An object of the present invention is to eliminate one or more of the above disadvantages.

This object is achieved by a system according to claim 1 and a method according to claim 7. Advantageous embodiments of the invention are specified in the dependent claims.

The advantages and configurations explained below in connection with the system or the cartridge also apply analogously to other objects of the invention and vice versa.

According to the invention, the two-component cartridge has an outer tube and an inner tube, which is located in the outer tube, and an inner chamber delimited by the inner tube and an outer chamber formed between the inner tube and the outer tube, the outer chamber serving to accommodate a first component. The cartridge is characterized in that an inner container, which serves to hold the second component, can be inserted into the inner chamber. In other words, the inner chamber serves to accommodate an inner container in which the second component is located.

The inner container can be inserted into the inner tube at any time, even just before the components are applied. It is therefore also possible with the two-component cartridge according to the invention to process such components, in particular such second components, which are comparatively chemically unstable, volatile and/or highly reactive. Since the inner containers can be stored separately, they can also be stored already prefilled and, if necessary, suitably packaged, for example in an airtight manner.

The invention enables the outer chamber to be filled with the first component and the inner container to be filled with the second component at different times and/or locations. In this way, production and warehousing of these parts can be optimized. In particular, separate storage of the cartridge housing and inner container is also possible. At the same time, there is an improvement in storage stability, since, for example, the cartridge housing with a first component that is stable in storage can be stored longer than the inner container with a second component that is less stable in storage. Larger quantities of cartridge housings can then be stored, for example, while the inner containers can be procured at shorter intervals if required. In this context, all the advantages of the exchange system explained below also come into play, in particular the possibility of selecting different second components, in particular the selection of components with different chemical compositions, different colors etc. as well as the possibility of different mixing ratios of the components depending on the application to provide for the application.

According to the invention, the inner container can be connected to the inner tube in an exchangeable manner. The inner container can therefore be changed if necessary. In this way, not only the cartridge housing can be used several times. With a suitable choice of the inner container, in particular the resulting mixing ratio of the components can also be changed in such an interchangeable system. In particular, a change in the volume content and/or the cross section of the inner container used is possible.

According to a preferred embodiment of the invention, the inner tube is connected to the outer tube in an exchangeable manner. In this way, inner and outer chambers with different sized intake volumes and/or with different sized outlets (outlet openings) can be provided and it can be done changing the inner tube changes the ratio of the cross-sectional areas and/or the capacity of the inner chamber and the outer chamber to one another. For example, by using different inner tubes, the cross-sectional area of the inner chamber can be enlarged/reduced, resulting in a reduction/enlargement of the cross-sectional area of the outer chamber. Depending on the design of the inner chamber, an inner container of a specific size, in particular with a specific cross-sectional area and a specific volume, can then be accommodated in the inner chamber. By using an inner tube of a certain size, the cross-sectional area and/or the capacity of the outer tube can be changed, so that the mixing ratio of the components can be changed in this way--even when using inner containers with identical cross-sections or volume contents.

Depending on the available capacity of the inner chamber, inner containers can also be used not only with different volume contents but also with different cross-sectional areas of the outlet opening; in this way the mixing ratio of the two components can be further changed. The ratio of both the capacity of the chambers and the cross-sectional areas of the outlet openings to one another can also be varied by changing the wall thickness of the inner tube. The mixing ratio can also be varied, even if the capacity of the chambers remains the same, by changing the wall thickness of the inner container and the resulting change in the outlet opening of the inner container.

An embodiment of the two-component cartridge in which both the inner container can be connected to the inner tube in an exchangeable manner and the inner tube is connected to the outer tube in an exchangeable manner is particularly advantageous. In this way, you can easily exchange and use suitable, coordinated inner containers and inner tubes provide a large number of different volume and/or cross-sectional ratios for the mixing, dosing and application of the two-component mixture.

With the help of the system according to the invention, almost any individual mixing ratio can be achieved automatically, i.e. by forced mixing within the cartridge. This is compared to the solutions known from the prior art, in particular with such

Mixing ratios advantageous that previously could only be mixed manually; for example, the ratio of the cross-sectional area (annular area) of the outer chamber to the cross-sectional area of the orifice exiting the inner chamber can be selected to provide an automatic mixing ratio of 8:1 (by volume).

According to a preferred embodiment of the invention, both components are expressed together with one and the same means. In this way, not only is there forced mixing in the mixing nozzle connected to the cartridge, but also forced dosing of the component mixture when it is applied.

According to a preferred embodiment of the invention, the inner container can be connected to the inner tube in an axially fixed manner, i.e. in such a way that movement of the inner container relative to the inner tube in the axial direction is precluded. In other words, the assembly of the inner container in the cartridge takes place with the production of an axially fixed connection between the inner container and the inner tube. This axial lock ensures correct dosing of the mixture even with different pressure ratios.

According to a preferred embodiment of the invention means are provided for forced pre-mixing of the components inside the cartridge, so that already in the inner tube Mixing of the components takes place. Since in this case forced mixing of the components already leaves the inner tube at its outlet opening, only a shorter mixing section is required to achieve a homogeneous mixing result.

Such forced pre-mixing takes place according to a preferred embodiment of the invention in that the inner tube has a plurality of outlet openings for the first component coming from the inner container and a plurality of inlet openings, preferably arranged offset to the outlet openings, for the second component coming from the outer chamber such that that the components passing through these openings flow radially towards one another; and/or by placing a static mixer inside the nozzle of the cartridge.

Fig. 1

einen Teil eines Außenrohres (perspektivisch),

Fig. 2

einen Teil eines Innenrohres (perspektivisch),

Fig. 3

einen Teil eines Innenbehälters (perspektivisch),

Fig. 4

einen Teil des Außenrohres (Mittellängsschnitt),

Fig. 5

einen Teil des Innenrohres (Mittellängsschnitt),

Fig. 6

einen Teil des Innenbehälters (Mittellängsschnitt),

Fig. 7

ein Detail des Kartuschenkopfes im montierten Zustand mit teilweise geschnittenen Rohrwänden,

Fig. 8

einen stark vereinfachten Querschnitt durch die Kartusche im Bereich der Öffnungen des Innenrohres,

Fig. 9

einen internen Mischer (perspektivisch),

Fig. 10

ein Detail eines Kartuschenkopfes (alternative Ausführung),

Fig. 11

ein Detail eines Kartuschenbodens mit Stempel des Ausdrückwerkzeugs mit teilweise geschnittenen Rohrwänden,

Fig. 12

eine Kartusche (alternative Ausführung) im montierten Zustand mit Mischdüse und Ausdrückwerkzeug (perspektivisch, geschnitten).

Exemplary embodiments of the invention are explained in more detail below with reference to the drawings. Here show:

1

a part of an outer tube (perspective),

2

a part of an inner tube (perspective),

3

a part of an inner container (perspective),

4

a part of the outer tube (central longitudinal section),

figure 5

a part of the inner tube (central longitudinal section),

6

a part of the inner container (central longitudinal section),

7

a detail of the cartridge head in the assembled state with partially sectioned tube walls,

8

a highly simplified cross section through the cartridge in the area of the openings of the inner tube,

9

an internal mixer (in perspective),

10

a detail of a cartridge head (alternative version),

11

a detail of a cartridge base with stamp of the ejection tool with partially cut tube walls,

12

a cartridge (alternative design) assembled with mixing nozzle and ejection tool (perspective, sectioned).

None of the figures show the invention to scale, but only schematically and only with its essential components. The same reference symbols correspond to elements with the same or comparable function.

The two-component cartridge 1 shown comprises a cylindrical outer tube 2 and a cylindrical inner tube 3 which is located in the outer tube 2 . Inner tube 3 and outer tube 2 are connected to each other and form the cartridge housing. The cartridge housing can be made in one piece or in several pieces. As illustrated, the cartridge housing is preferably designed in two parts, in particular in such a way that the parts produced by means of a plastic injection molding process can be demoulded without any problems. In this connection it is particularly advantageous that the cartridge housing according to the invention can be produced using conventional standard outer tubes 2 . In this way, suitable inner tubes 3 only have to be made. The inner tube 3 is interchangeably connected to the outer tube 2, so it can be changed if necessary.

The inner tube 3 rests with the outside of its end wall 4 on the inside of the end wall 5 of the outer tube 2, while the neck 6 of the inner tube, which extends axially from the end wall 4 3 extends into the neck 7 of the outer tube 2 extending axially from the end wall 5 . The outer diameter of the neck 6 of the inner tube 3 is adapted to the inner diameter of the neck 7 of the outer tube 2 in such a way that the inner tube neck 6 can be inserted into the outer tube neck 7 and fastened there, forming a preferably detachable latching or snap connection. The necks 6, 7 have suitable connecting elements for forming such a connection.

The inner container 8 can be connected to the inner tube 3 in an exchangeable manner, i.e. the inner container 8 can also be removed from the inner tube 3 again and, if necessary, exchanged for another inner container 8 .

The cartridge 1 further comprises an inner chamber 12 bounded by the inner tube 3 and an outer chamber 11 formed between the inner tube 3 and the outer tube 2 when the inner tube 3 is assembled, the outer chamber 11 serving to accommodate a first component, for example a base component. The two separate chambers 11, 12 are arranged coaxially, namely "tube-in-tube". In this way, the cartridge 1 can be manufactured and used in a particularly simple manner.

A second component, for example a hardener, which carries out a desired chemical reaction together with the base component, is located in an inner container 8 . This inner container 8 can be inserted into the inner chamber 12 . For this purpose, the inner container 8 is opened, for example by the outlet opening 9 of the inner container 8 being cut open. The inner container 8 is then pushed into the inner tube 3 of the cartridge 1 from behind. In the assembled state, the inner container 8 lies with its outer wall in the inner tube 3 with a precise fit and with the outside of its end wall 10 on the inside of the end wall 4 of the inner tube 3 .

The outlet opening 9 of the inner container 8 is located at the head end of the inner container, in its end wall 10. An outlet connection 13 is provided there for this purpose, which in the installed state fits exactly into a correspondingly shaped, central receiving opening 14 in the end wall 4 of the inner tube 3. Due to the conical or cone-shaped design of the outlet connector 13 and the corresponding design of the receptacle 14, a self-sealing transition from the inner container 8 to the inner tube 3 takes place in the assembled state.

In the assembled state, the inner container 8 is axially fixed to the inner tube 3 . In the illustrated example, the inner container 8 is screwed to the inner tube 3 and has a suitable external thread 15 which interacts with a corresponding internal thread 16 of the inner tube 3 . However, the inner container 8 can also be connected in an axially fixed manner to the inner tube 3 in some other way.

Both components are expressed together with one and the same means. A standard cartridge press can be used to press out the components, provided it is equipped with an appropriate press-out tool. A suitable squeezing tool 20 has, instead of a piston with a circular ram, a split piston 21 with ram surfaces spaced apart from one another, which in the installed state have a ram ring 22 on the base 17 of the outer chamber 11 on the one hand and an inner ram 23 on the base 18 of the inner container 8 on the other act, but not on the inner tube 3 or its wall. In the 11 , 12 only the squeezing tool 20 is shown, but not the cartridge gun itself.

For application of the component mixture, a nozzle 24 is screwed onto the neck 7 of the outer tube 2 and has a static helical mixer 25 in its interior. If there is no mixing of the components in the inner tube 3 (as in the alternative embodiment, as in 10 pictured), then an unmixed mass of components is added from the cartridge 1 to the helical mixer 25 of the mixing nozzle 24 . In this embodiment, the second component coming from the inner container 8 leaves the socket-shaped axially elongated receiving opening 14 running in the neck 6 of the inner tube as a central strand and is carried by the first component coming from the outer chamber 11, which is located in the annular space between the nozzle-shaped extended receiving opening 14 and the inner wall of the neck 6 of the inner tube 3 is formed, wrapped and embedded in it. Both components are thus brought together in the mouthpiece 30 of the inner tube 3 and leave the inner tube 3 at its outlet 31 in the neck 7 of the outer tube 2.

However, the components are preferably already mixed in the inner tube 3 . Forced pre-mixing can take place in that the inner tube 3 in the area of its mouthpiece 30 not only conducts the second component further axially in the direction of the outlet 31, but instead in the axial continuation of the receiving opening 14 of the inner tube 3, directly to the outlet connection 13 of the inner container 8 subsequently, a plurality of outlet openings 32 running in the radial direction are provided, through which the second component flows radially from the inside outwards into the mouthpiece 30 of the inner tube 3 when the components are applied (arrow 34). These outlet openings 32 are, as in 8 illustrated, arranged offset to the inlet openings 33 of the inner tube 3, through which the first component flows radially from the outside inward from the outer chamber 11 into the mouthpiece 30 of the inner tube 3 during application (arrow 35). The two components flow in opposite directions, which inevitably results in a first mixing of these components before they move further in the axial direction 26 in the direction of the outlet 31 , leave the cartridge 1 and pass into the mixing nozzle 24 . In this way, the second component is no longer guided axially into the mouthpiece 30, where it is separated from the first component, which enters the mouthpiece 30 through inlet openings 33 in the inner tube 33, at the outlet 31 is sheathed, as in 10 pictured. Instead, the two components are directed towards one another, namely both radially and offset from one another, so that premixing already takes place before leaving the cartridge 1 .

As an alternative or in addition to this mixing based on countercurrent flow, a static mixer can already be integrated inside the cartridge head, more precisely in the mouthpiece 30 of the inner tube 3 . In order to achieve forced premixing in this way, a mixer helix 27 is arranged immediately after the offset inlet and outlet openings 32, 33 of the inner tube 3, with its rear part still in the neck 6 of the inner tube 3, with its front part is already in the neck 7 of the outer tube 2 and ends with this.

The mixer helix 27 is manufactured as a separate component and can be inserted into the mouthpiece 30 of the inner tube 3 to form a latching or snap connection, for which purpose suitable connection elements are provided on the mixer helix 27 and the inner tube 3 .

Preferably, the mixer helix 27 has a geometry that has three material guides 19 per mixing segment 28, while previously known mixers have only two material guides per mixing segment. In addition, the twist direction change of the individual material guides 19 in the proposed mixer helix 27 takes place axially offset. In the example shown, the mixer helix 27 has three mixing segments 28 arranged in axial succession, the rear mixing segment having a right-hand twist, the middle mixing segment a left-hand twist and the front mixing segment again a right-hand twist. The twist direction change offset 29 is clearly recognizable at the transitions between the mixing segments 28 .

All of the features presented in the description, the following claims and the drawing can be used individually as well be essential to the invention in any combination.

Reference List

1

cartridge

2

outer tube

3

inner tube

4

end wall of the inner tube

5

end wall of the outer tube

6

neck of the inner tube

7

neck of the outer tube

8th

inner container

9

outlet opening of the inner container

10

front wall of the inner container

11

outer chamber

12

inner chamber

13

Inner tank outlet

14

opening of the inner tube

15

External thread of the inner container

16

Internal thread of the inner tube

17

floor of the outer chamber

18

bottom of the inner container

19

material handling

20

squeezing tool

21

Pistons

22

stamp ring

23

inner stamp

24

nozzle, mixing nozzle

25

Spiral mixer of the nozzle

26

axial direction

27

mixing helix

28

mixed segment

29

Offset of the mixing segments when changing the direction of twist

30

mouthpiece of the inner tube

31

outlet of the inner tube

32

outlet opening of the inner tube

33

inlet opening of the inner tube

34

Flow direction of the first component

35

Flow direction of the second component

Claims (7)

1. System comprising

   a two-component cartridge (1) with an outer tube (2) and with an inner tube (3) which is situated in the outer tube (2) and with an inner chamber (12) which is bounded by the inner tube (3) and with an outer chamber (11) which is formed between the inner tube (3) and the outer tube (2), wherein the outer chamber (11) serves for accommodating a first component,
   and

   an inner container (8) which is configured for insertion into the inner tube (3) of the cartridge (1) and is inserted into the inner tube (3) of the cartridge (1) and serves for accommodating a second component,

   characterized in that the inner container (8) is exchangeably connectable to the inner tube (3).
2. System according to Claim 1, characterized in that the inner tube (3) is exchangeably connected to the outer tube (2).
3. System according to Claim 1 or 2, characterized in that the inner container (8) is connectable in an axially fixed manner to the inner tube (3).
4. System according to one of Claims 1 to 3, characterized by means for forced mixing of the components in the interior of the cartridge (1).
5. System according to Claim 4, characterized in that the inner tube (3) has a plurality of exit openings (32) for the first component, which comes from the inner container (8), and has a plurality of entry openings (33), preferably arranged offset from the exit openings (8), for the second component, which comes from the outer chamber (11), in such a way that the components passing through these openings (32, 33) flow radially against one another.
6. System according to Claim 4 or 5, characterized in that a helical mixer (27) is fitted in the interior of the cartridge head.
7. Method in which, for forming a system according to one of Claims 1 to 6, an inner container (8) configured for insertion into the inner tube (3) of a two-component cartridge (1) and serving for accommodating a second component is inserted into an inner tube (3) of the cartridge (1) and is exchangeably connected, which cartridge (1) has an outer tube (2) and the inner tube (3), which is situated in the outer tube (2), wherein the cartridge (1) has an inner chamber (12) which is bounded by the inner tube (3) and has an outer chamber (11) which is formed between the inner tube (3) and the outer tube (2), wherein the outer chamber (11) serves for accommodating a first component, and wherein the inner container (8) is insertable into the inner chamber (12).

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