MEASURING AND MIXING DEVICES

Abstract

The present disclosure relates to a metering and mixing device including a cartridge holder (1) and a cartridge (2). A surface-to-surface, and also positive and non-positive connection exists between the cartridge and the holder. The present disclosure also relates to a method for coating substrates with two- or multicomponent coating media, in which the metering and mixing device is used.

Claims

1. A metering and mixing device comprising: i. a cartridge holder comprising: (a) a receiving container for multichamber cartridges; and (b) a compressed air connection and a connection for an application device; and ii. a multichamber cartridge inserted into the cartridge holder according to i., wherein said cartridge comprises the following sections: an upper section, comprising a directional control valve; a central section, comprising a space which is extended in the direction of the longitudinal axis of the cartridge and is fitted with static mixing elements, and also at least two adjacent chambers, wherein the chambers are arranged so as to be extended in the direction of the longitudinal axis of the cartridge, and adjacent chambers are separated from one another by a common partition wall, and each chamber is connected to the upper section by in each case at least one opening; and a lower section, which comprises a piston for each of the chambers, wherein the pistons close off the chambers leaktightly from below and are connected to one another by cutting devices, and the cutting devices are arranged in such a way that they are capable of severing the common partition wall of respective adjacent chambers when the pistons are moved in the direction of the upper section, wherein the multichamber cartridge and the cartridge holder have mutually complementary means for the production of a reversible joint-type connection between the cartridge and the holder, and wherein a surface-to-surface, positive and non-positive connection including the entire circumference of the cartridge, furthermore exists between the cartridge and the holder in the closed state of the reversible joint-type connection.

2. The metering and mixing device according to claim 1, wherein the multichamber cartridge is embodied as a coaxial cartridge and comprises the following sections: an upper section, comprising a directional control valve; a central section, the center of which is designed, in the direction of the longitudinal axis, as an extended space fitted with static mixing elements, and the space is surrounded by at least two chambers, wherein the chambers are arranged so as to be extended in the direction of the longitudinal axis of the cartridge and are arranged coaxially with respect to one another and with respect to the space, and adjacent chambers are separated from one another by a common partition wall, and each chamber is connected to the upper section by in each case at least one opening; and a lower section, which comprises a piston for each of the chambers, wherein the pistons close off the chambers leaktightly from below and are connected to one another by cutting devices, and the cutting devices are arranged in such a way that they are capable of severing the common partition wall of respective adjacent chambers when the pistons are moved in the direction of the upper section.

3. The metering and mixing device according to claim 2, wherein the coaxial cartridge has a tubular space and two chambers, and the space and the chambers are formed by a coaxial arrangement of three tubes, wherein an inner tube surrounds the tubular space, the outer surface of the inner tube and the inner surface of the central tube form a first chamber, which is closed off in the direction of the lower section by a first piston and is closed off in the direction of the upper section by an opening leading to the upper section, and the outer surface of the central tube and the inner surface of the outer tube form a second chamber, which is closed off in the direction of the lower section by a second piston and is closed off in the direction of the upper section by an opening leading to the upper section.

4. The metering and mixing device according to claim 1, wherein the space also extends through the lower section of the multichamber cartridge and has a fluid-carrying connection to the connection.

5. The metering and mixing device according to claim 1, wherein the cutting devices are embodied in the form of wedge-shaped gaps.

6. The metering and mixing device according to claim 1, wherein a premixing chamber is integrated into the directional control valve.

7. The metering and mixing device according to claim 1, wherein the central section of the multichamber cartridge accounts for at least 60%, of the total length of the cartridge.

8. The metering and mixing device according to claim 1, wherein the receiving container of the cartridge holder is designed as a receiving shell, and the cartridge holder thus only partially covers the cartridge arranged therein.

9. The metering and mixing device according to claim 8, wherein the cartridge holder covers only the lower section or the lower section and a lower partial region of the central section of the cartridge.

10. The metering and mixing device according to claim 8, wherein the means for producing the reversible joint-type connection are arranged in such a way that, relative to the cartridge, the at least one joint is set up in a lower partial region of the central section thereof and/or an upper partial region of the lower section thereof.

11. The metering and mixing device according to claim 1, wherein the cartridge has a label on the large-area outer wall thereof.

12. The metering and mixing device according to claim 1, wherein the surface-to-surface, positive and non-positive connection including the entire circumference of the cartridge and of the surface-to-surface exclusively positive connection including the entire circumference of the cartridge extends over an upper partial region of the lower section of the cartridge and/or a lower partial region of the central section.

13. The metering and mixing device according to claim 1, wherein, in addition to the surface-to-surface, positive and non-positive connection including the entire circumference of the cartridge, a surface-to-surface, exclusively positive connection including the entire circumference of the cartridge is furthermore present.

14. The metering and mixing device according to claim 13, wherein the entire surface of the surface-to-surface, a positive and non-positive connection including the entire circumference of the cartridge and of the surface-to-surface, exclusively positive connection including the entire circumference of the cartridge extends over no more than 30%, of the total length of the cartridge.

15. A method for delivering, metering and mixing two or more components, characterized in that a metering and mixing device according to claim 1 is used to carry out the method.

16. A method for coating substrates with two- or multicomponent coating media, characterized in that, to apply a coating, the metering and mixing device according to claim 1 is connected to a paint spray gun, the components are delivered pneumatically into the upper section of the metering and mixing device and delivered in the opposite direction through the static mixing elements, being mixed in the process, and the resulting homogeneous mixture of the components is then fed to the paint spray gun and applied via the latter to the substrate.

17. The method according to claim 16, wherein application is interrupted once or several times, the multichamber cartridge is cleaned during the interruption of the application, and the application is continued after the cleaning of the multichamber cartridge, using the same multichamber cartridge or a different multichamber cartridge of identical construction.

Description

[0039] The attached FIGS. 1 to 6 serve to explain the present invention. The following reference signs are used:

[0040] (1) cartridge holder, (1.1) receiving container for multicomponent cartridges, (1.2) compressed air connection, (1.3) connection for an application device, (2) multichamber cartridge, (2.1) upper section of the multichamber cartridge, (2.1.1) directional control valve, (2.2) central section of the multichamber cartridge, (2.2.1) space extended in the direction of the longitudinal axis of the cartridge and fitted with static mixing elements, (2.2.1.1) static mixing elements, (2.2.2) chambers, (2.2.4) partition wall between adjacent chambers, (2.2.5) openings of the chambers of the central section of the multichamber cartridge toward the upper section of the multichamber cartridge, (2.3) lower section of the multichamber cartridge, (2.3.1) piston, (2.3.3) cutting device, (4) connection for flushing media, (5) or (5a) and (5b) means for producing a reversible joint-type connection between the holder and the cartridge, (6) reversible joint-type connection, (7a) region of surface-to-surface positive connection including the entire circumference of the cartridge, (7b) region of surface-to-surface positive and non-positive connection including the entire circumference of the cartridge, (A) interface in the partition wall between two adjacent chambers, (B) cut in the partition wall between two adjacent chambers.

[0041] FIG. 1 shows a cartridge holder to be used according to the invention. FIGS. 1a and 1b show detail views of regions of the cartridge holder comprising means (5a) for producing a reversible joint-type connection (6).

[0042] FIG. 2 shows a cartridge to be used according to the invention. FIGS. 2a and 2b show detail views of regions of the cartridge comprising means (5b) for producing a reversible joint-type connection (6).

[0043] FIG. 3 shows a metering and mixing device according to the invention, which comprises the component parts described in FIGS. 1 and 2. FIGS. 3a and 3b show detail views of regions of the metering and mixing device which comprise a reversible joint-type connection (6) in the closed state. Regions of surface-to-surface positive and/or non-positive connections (7b) are furthermore shown.

[0044] FIGS. 4a and 4b show alternative regions to those in FIGS. 3a and 3b, comprising a reversible joint-type connection (6) in the closed state. Both regions of surface-to-surface, purely positive connections (7a) and regions of surface-to-surface positive and/or non-positive connections (7b) are shown.

[0045] FIG. 5 likewise shows an alternative region comprising a reversible joint-type connection (6) and a region of surface-to-surface connection. Here once again, the surface-to-surface connection (7b) is of positive and non-positive design, wherein it is not planar (FIGS. 3a and 3b) but conical in configuration.

[0046] FIG. 6 also shows an alternative region of this kind. Here, both a region of surface-to-surface, purely positive connection (7a) and a region of surface-to-surface positive and non-positive connection (7b) are shown.

[0047] First of all, some of the terms used in the context of the present invention will be explained.

[0048] Where reference is made in the context of the present invention to a space extended in the direction of the longitudinal axis or to a corresponding chamber, this means that the space or chamber has the greatest extent in the direction of said axis. Here, the space or chamber can be shaped, in particular, as a cylinder or prism, in particular as a right cylinder or right prism, wherein the respective cavity present forms the space or chamber. Circular cylinders, elliptical cylinders or even ultimately prisms that are arbitrarily shaped and individually adapted in respect of their cross-sectional area are possible. Instead of a complete circular ring, segments of an imaginary circular ring are also possible as cross-sectional area geometries, for example. Thus, a cross-sectional area in the form of a circular ring can be divided into two or more segments of equal or different size and thus into different extended regions (space, chambers). Here, boundaries of the segments are formed by partition walls, e.g. partition walls of adjacent chambers. Of course, almost any other geometries can be implemented. Thus, for example, individual tubes of circular cross-sectional area can also replace the right hollow cylinders with a cross-sectional area in the form of a circular ring segment.

[0049] Where reference is made in the context of the present invention to a reversible joint-type connection, this should be taken to mean a connection between two elements which can be produced (closed) and opened (released) variably. The production of the connection (i.e. closure) and hence, logically, also the opening of the connection (i.e. release) is achieved by means of mutually complementary means on the elements to be connected. A joint-type connection of this kind can be achieved by means of at least one bayonet joint or at least one screw-threaded joint, for example. The means for producing a joint-type connection of this kind are then attached to the elements to be connected and accordingly correspond to one another (are mutually complementary). In the case of a bayonet joint, the corresponding means are a longitudinal slot having a transverse slot, which starts at the end thereof, and a knob, which is introduced into the longitudinal slot and is then anchored in the transverse slot by a rotary motion which then follows. In the case of a screw-threaded joint, the corresponding means are threaded pieces which have a screw thread comprising at least one thread flight and a corresponding screw thread.

[0050] Even if it is fundamentally known that a bayonet joint can likewise be assigned to the group of screw-threaded joints (where the transverse slot then counts as a thread flight), a distinction is drawn between them in the context of the present invention for the sake of clarity. A joint referred to in the context of the present invention as a bayonet joint is one in which the thread flight does not have a slope in the direction of the torque of the closing direction of rotation (i.e. thread pitch=0 or even, to allow spring back and anchoring of the knob, an opposing thread pitch).

[0051] Thus, in the correspondingly narrower sense, joints in which the at least one thread flight of a screw thread has a thread flight in the direction of the torque of the closing direction of rotation are regarded as screw-threaded joints.

[0052] If two elements, in particular a cartridge and a cartridge holder, are connected by closing a joint-type connection that is reversible as described, there is a certain connection between the elements, depending on the configuration of the means (5) and the geometrical shape of the connected elements. The connection can be limited to the means (5), for example. Equally, however, there can furthermore be a connection which goes beyond the region of the means (5) and, in particular, results from the geometries of the elements to be connected. Thus, it is at least possible for there to be a surface-to-surface connection in addition. In that case, therefore, a surface of one element then rests against a surface of the other element. Of course, it is also possible in each case for a plurality of surface pairs to rest one against the other. A surface-to-surface connection as described is essential in the context of the present invention. By definition, a surface-to-surface connection of this kind is distinct from connections existing directly in the region of means (5).

[0053] As regards the type of connection, a distinction should be made between a purely positive and a non-positive connection. When connecting two elements, it is, of course, also possible for there to be both regions (surfaces resting one against the other) with a purely positive connection (7a) and regions with both a positive and a non-positive connection (7b). Whereas, in the case of a positive connection, regions of the elements merely rest one upon the other or one against the other, there is an explicit normal force acting on the connection regions in the case of non-positive engagement. In the context of the present invention, this normal force and hence the non-positive engagement is preferably brought about by connecting the means (5). If, for example, two screw threads are rotated one inside the other, then, given appropriate geometries and alignment of surface areas of the elements to be connected, there can be a normal force acting in the direction of the torque of the twisting of the screw thread.

[0054] This is the case when there are element regions to be connected (surfaces resting one against the other) which are not arranged strictly parallel to the torque of the twisting of the screw threads (see also FIGS. 3a, 3b, 4a, 4b, 5 and 6).

[0055] Where reference is made in the context of the present invention to upper, central and lower sections of a cartridge, this encompasses first of all the relative arrangement of corresponding regions. However, the sections or regions per se are furthermore defined especially by means of the technical designs arranged therein (see above). Here, the individual dimensioning of the individual sections or regions is not in the first instance subject to any restrictions in principle.

[0056] Both various essential aspects of the present invention and preferred embodiments of the metering and mixing devices according to the invention are described in greater detail below.

[0057] Preferably, the multichamber cartridge (2) of the metering and mixing device according to the invention has a central section (2.2), the center of which is designed as a space (2.2.1) that extends in the direction of the longitudinal axis of the cartridge and is fitted with static mixing elements (2.2.1.1), and wherein the space (2.2.1) is surrounded by at least two chambers (2.2.2), wherein the chambers are arranged so as to be extended in the direction of the longitudinal axis of the cartridge, and adjacent chambers are separated from one another by a common partition wall (2.2.4), and each chamber (2.2.2) is connected to the upper section (2.1) by in each case at least one opening (2.2.5).

[0058] The multichamber cartridge (2) of the metering and mixing device according to the invention is preferably embodied as a coaxial cartridge for a cartridge holder (1) of the kind defined above, wherein the cartridge comprises the following sections:

[0059] an upper section (2.1), comprising a directional control valve (2.1.1);

[0060] a central section (2.2), the center of which is designed, in the direction of the longitudinal axis, as an extended space (2.2.1) fitted with static mixing elements (2.2.1.1), and the space (2.2.1) is surrounded by at least two chambers (2.2.2), wherein the chambers are arranged so as to be extended in the direction of the longitudinal axis of the cartridge and are arranged coaxially with respect to one another and with respect to the space (2.2.1), and adjacent chambers are separated from one another by a common partition wall (2.2.4), and each chamber is connected to the upper section (2.1) by in each case at least one opening (2.2.5); and

[0061] a lower section (2.3), which comprises a piston (2.3.1) for each of the chambers, wherein the pistons (2.3.1) close off the chambers (2.2.2) leaktightly from below and are connected to one another by cutting devices (2.3.3), and the cutting devices (2.3.3) are arranged in such a way that they are capable of severing the common partition wall (2.2.4) of respective adjacent chambers (2.2.2) when the pistons (2.3.1) are moved in the direction of the upper section (2.1).

[0062] Such a construction can be obtained, for example, by coaxial arrangement of three tubes or circular cylinders one inside the other. Here, the inner tube surrounds the space (2.2.1). The space between the outer surface of the inner tube and the inner surface of the central tube forms a first chamber (2.2.2) closed off in the direction of the lower section (2.3) by a piston (2.3.1) and closed off in the direction of the upper section (2.1) by an opening (2.2.5) leading to the upper section (2.1). The space between the outer surface of the central tube and the inner surface of the outer tube forms a second chamber (2.2.2) closed off in the direction of the lower section (2.3) by a further piston (2.3.1) and closed off in the direction of the upper section (2.1) by an opening (2.2.5) leading to the upper section (2.1).

[0063] In said preferred embodiments, the lateral walls of the chambers and of the space are therefore arranged coaxially. This therefore also means that, in these preferred embodiments, the surface lines of a chamber and of a space run strictly parallel. Accordingly, the space (2.2.1) and the chambers (2.2.2) are in the form of right circular cylinders arranged coaxially with one another.

[0064] However, this does not necessarily mean that the outer side wall of the cartridge must simply follow this course. On the contrary, the possibility of having demolding chamfers in this region of the cartridge is advantageous, said chamfers leading to the advantages described at the outset in connection with the production process.

[0065] As already noted above, the terms “upper”, “central” and “lower” section in the first instance described only the relative arrangement of the sections. However, the fact that spaces and chambers extended in the direction of the longitudinal axis of the cartridge (2) are arranged in the central section (2.2) of the cartridge furthermore entails that this central section preferably accounts for the majority of the length of the cartridge. As a particular preference, the central section (2.2) of the cartridge (2) accounts for at least 50%, preferably at least 60%, as a further preference at least 75%, of the total length of the cartridge (2). The respective residual portion of the length, e.g. at most 50%, preferably at most 40%, as a further preference at most 25%, is then made up, in particular, of the upper section (2.1) and the lower section (2.3).

[0066] As described above, the metering and mixing device according to the invention has a cartridge holder (1). This cartridge holder comprises a receiving container for the cartridge (2).

[0067] Ultimately, the receiving container and the shape thereof can be chosen arbitrarily as long as the type, described below in greater detail, of surface-to-surface and positive and non-positive connection between the cartridge (2) and the cartridge holder (1) is achieved when the joint-type connection (6) is closed.

[0068] In this context, it is possible, for example, for the receiving container to cover the lateral walls of the cartridge as far as the region of the upper section preferably without resting in positive contact over the entire central section, e.g. through corresponding geometrical configuration of the outer side wall of the cartridge (2) and/or of the lateral inner wall of the holder (1) or lateral inner wall of the container (1.1)). The means (5) for producing the reversible joint-type connection (6) can then be arranged in the upper section (2.1) but also in the central section (2.2) or lower section (2.3). Of course, there can also be multiple instances of complementary means (5), and therefore the reversible joint-type connection (6) can comprise a plurality of joints, e.g. bayonet joints and/or screw-threaded joints.

[0069] The preference that the cartridge holder does not rest in positive contact over the entire central section of the cartridge has specific advantages. These advantages consequently also apply in particular with respect to the device described in WO 2016/020129 A1.

[0070] The introduction of the cartridge into the holder, which must generally be performed by hand, is relatively complicated whenever the cartridge holder rests in positive contact over the entire central section of the cartridge. Introducing the cartridge even at only a slight angle can lead to catching and jamming. An advantage of the above-described embodiment is thus that a relatively easy introduction process of the cartridge is provided.

[0071] Another disadvantage of the positive contact over the entire central section of the cartridge is the somewhat complex problem of marking the cartridge. Thus, owing to the large-area positive contact between the cartridge in the holder, it is only with difficulty that the large-area outer wall (side wall) of the cartridge can be labeled with a label (also referred to as a body label) and that a cartridge labeled in this way can be introduced into the overall device. The label will generally be too thick and/or may crease during the process of introduction, thus making effective sealing for pressure buildup or even the introduction of the cartridge impossible. There is then only the possibility of applying small labels, which have to be glued on in positions which are less easily visible. However, in many areas of industry in which corresponding multicomponent systems are to be used, it is necessary to adequately label materials and, at the same time, also to provide hazard or safety symbols and explanations, for example. It is only with difficulty that this can be achieved on small labels.

[0072] An advantage of the embodiment described above is consequently that there is an optimized and individually adaptable possibility of labelling the large-area outer wall of the cartridge. It is accordingly also preferred in the context of the present invention that the cartridge (2) has a label on the large-area outer wall (side wall) thereof.

[0073] It is particularly preferred that the receiving container (1.1) is designed as a receiving shell. This obviously means that the receiving container (1.1) only partially covers the cartridge (2) arranged therein, that is to say preferably only the lower section (2.3) or the lower section (2.3) and a lower partial region of the central section (2.2) of the cartridge (2).

[0074] In this preferred embodiment, the means (5) for producing the reversible joint-type connection (6) are then arranged in such a way that, relative to the cartridge (2), the at least one joint is set up in a lower partial region of the central section (2.2) thereof and/or an upper partial region of the lower section (2.3) thereof. There is preferably precisely one joint.

[0075] The embodiment described (receiving shell) has particular advantages. On the one hand, the above-described introduction of the cartridge into the holder is made even easier by this type of construction. This is because only a very small quantity of air must be displaced in these embodiments as the cartridge is introduced into the holder.

[0076] Fundamentally, it is the case that the air between the cartridge and the holder is compressed during the introduction process because of the positive and non-positive connection between the cartridge and the cartridge holder. If, however, there is a relatively large air volume before compression, the air, which is then compressed to a high pressure, must be discharged via a very difficult-to-produce topography of the cartridge holder surface over the majority of the introduction path before positive and non-positive sealing takes place. The backpressure which then still arises must be overcome by the painter through the expenditure of an increased force. Alternatively, the air can be discharged via a valve in the cartridge holder, and it is then necessary to re-close this valve after introduction.

[0077] In the embodiments described above, however, only a very small air volume has to be displaced and compressed, and therefore the disadvantages enumerated in the previous paragraph do not exist.

[0078] Similar advantages apply to the already described labeling of the lateral outer wall of the cartridge (2). The described construction of the receiving shell makes this type of labeling even easier.

[0079] Another advantage of the type of construction described for the receiving shell (1.1) results from the following circumstance. It is known that the materials used in connection with the component parts that form the subject matter here, that is to say, in particular, plastics, should generally have good mechanical and also chemical resistance. It likewise known that it is generally impossible to obtain these properties from plastics which are transparent in any layer thicknesses but are more translucent above a certain thickness. Polypropylene may be mentioned by way of example. If two walls (of the cartridge and the cartridge holder) in layer thicknesses that are sufficient in respect of the mechanical requirements are then used, visual perception of the interior pistons and hence of the level of material in the chambers is very difficult. Moreover, the double wall described results in a relatively high weight, which is less comfortable for the painter. Through the use of the abovementioned shell (1.1), the disadvantages described in respect of a lack of visibility of the level and of high weight are avoided.

[0080] As regards the type of joint, a screw-threaded joint is preferred. This is because it is precisely a screw-threaded joint which offers particular advantages in connection with air-assisted systems such as the metering and mixing device according to the invention under consideration here. This is because, to the extent that a device that is still under pressure is to be unscrewed, it would be possible, in the case of progressive unscrewing of the joint, for the compressed air to escape at a point in time at which there was still engagement between a sufficiently large number of thread flights and corresponding thread flights and/or between a sufficiently long section of just one thread flight and a section of a corresponding thread flight, thus ensuring that the component parts to be separated did not fly apart in an uncontrolled manner. This advantage obviously does not exist as distinctly in the case of a bayonet joint. Moreover, non-positive engagement, as described below and as preferred, can be achieved in a very good and definite way by means of a screw-threaded joint.

[0081] In principle, the screw-threaded joints can be configured in any desired manner as long as the abovementioned criteria in respect of the thread pitch of the thread flights are satisfied. Thus, the screw threads of the joints can have a single flight or multiple flights. A thread flight can form one or even several complete turns. Equally, a thread flight can also form less than one turn.

[0082] In the context of the present invention, there is a preference for screw-threaded joints in which the corresponding screw threads have thread flights which form no more than one complete turn, preferably no more than half a turn, e.g. one third of a turn. This ensures very simple assembly of the metering and mixing device. In order to achieve a necessary or desirable strength of the joint-type connection, these are then preferably multi-flight screw threads. This means that a screw thread has at least two thread flights, preferably 2 or 3 thread flights. Of course, the respectively corresponding screw thread then has the corresponding number of thread flights.

[0083] According to the invention, it is envisaged that, in the closed state of the reversible joint-type connection (6), there is furthermore between the cartridge (2) and the holder (1) a surface-to-surface, positive and non-positive connection including the entire circumference of the cartridge.

[0084] How such a surface-to-surface and positive and non-positive connection can be achieved in principle is already evident from the information mentioned above. Details and illustrative embodiments thereof are described below. At the same time, it is only the type of connection and the precise position of the surface-to-surface connection which will be explored in detail. The way the means (5) and hence the reversible joint-type connection (6) are to be arranged and/or which geometries the elements comprising the cartridge (2) and the holder (1) must have in this context, for example, can be adapted without problems in each individual case by a person skilled in the art.

[0085] Of course, there is a requirement that the specified connection should include the entire circumference of the cartridge. Only in this way is it possible to achieve a pressure buildup as described below. It is therefore also clear that the individual choice of a region or partial region is only possible by means of the dimensioning existing in the direction of the longitudinal axis of the cartridge. Owing to the fixed dimensioning, namely the circumference of the cartridge, and an individually selectable extent in relation to the longitudinal axis of the cartridge, a connecting surface or a surface-to-surface connecting region is obtained.

[0086] There is in any event a surface-to-surface connection that is both positive and non-positive ((7b), definition see above). This of course does not however rule out the possibility of there also being further surface-to-surface connections that are purely positive ((7a), definition see above). When simply a “connection” is mentioned, this is meant here as a general term for one or more connecting regions that in any event comprise at least one connection (7b), but optionally also at least one connection (7a). Therefore, in any event a plurality of connecting regions or connecting positions (connecting surfaces) may be implemented.

[0087] It is possible, for example, for the connection to extend over a partial region of the upper section (2.1) of the cartridge. In this case, the partial region, in particular, of the upper section which is to be assigned to the lateral walls or the encircling side wall of the cartridge would then be provided for connection to the cartridge holder, namely a partial region of the lateral inner wall of the container (1.1). This is because the upper side (end side) of the cartridge and the corresponding partial region of the upper section (2.1) is obviously unsuitable for such a connection since, to achieve this, the cartridge holder would have to be correspondingly arranged above the upper side of the cartridge, making it impossible in practice to introduce the cartridge into the holder.

[0088] It would also be possible for the connection to extend over at least a partial region of the lower section (2.3) of the cartridge. Here too, the partial region, in particular, of the lower section which is to be assigned to the lateral walls or the encircling side wall of the cartridge would then be provided for connection to the cartridge holder, namely a partial region of the lateral inner wall of the container (1.1). Admittedly, the underside of the cartridge and the corresponding partial region of the lower section (2.3) can likewise be used to produce such a connection. However, at least a complete connection on the underside does not appear to be very advantageous. This is because there should be a space for the buildup of pressure via the compressed air connection (1.2) between the underside of the cartridge (2) and the inner side of the base of the cartridge holder (1). Moreover, component parts such as the compressed air connection (1.2) and the connection for the application device (1.3) occupy a certain volume within the cartridge holder, with the result that a complete connection of the cartridge and the holder in this region would be possible only by means of an extremely complex cartridge geometry.

[0089] A connection which extended over the central section, preferably only a partial region of the central section (2.2) (see above) would likewise be possible, for example. It is advantageous if such a connection accounts for no more than 50%, preferably no more than 25%, as a further preference no one 10%, of the total length of the section (2.2).

[0090] It is advantageous for the connecting surface which is present overall to extend over no more than 30%, preferably no more than 15%, as a further preference no more than 5%, of the total length of the cartridge.

[0091] If more than one connecting position and hence different connecting regions are implemented in the abovementioned sense, it is obviously required that each individual region should be of surface-to-surface design and designed so as to include the entire circumference of the cartridge, wherein at least one of these connections is positive and non-positive. However, this does not, of course, exclude the existence of further connecting surfaces which do not include the entire circumference of the cartridge, for example. Of course, these connecting surfaces are then not connecting surfaces in the abovementioned sense and can be based, for example, on particular individual construction geometries of the cartridge and/or the holder.

[0092] In the context of the present invention, it is preferred that the at least one surface-to-surface connection (7b) and the optionally present at least one surface-to-surface connection (7a) extend over an upper partial region of the lower section (2.3) of the cartridge and/or a lower partial region of the central section (2.2).

[0093] This arrangement of the surface-to-surface connection is obviously suitable as a particular preference in connection with the above-described embodiments relating to the receiving shell.

[0094] In the context of the present invention, it is fundamentally preferred that the geometrical shapes of the cartridge and the cartridge holder are configured and matched to one another in such a way that a positive and non-positive as well as optionally exclusively positive connection is not established before the end of the process of introducing the cartridge into the cartridge holder. This means that, after the initial partial production of such a connection, the cartridge does not have to be pushed further to any significant extent but must merely be brought into the end position to produce the connection intended overall. This ensures that, even in the case of embodiments in which the container (1.1) is not designed as a shell, the above-described advantages in respect of avoiding a high pressure buildup due to compression of a large air volume are obtained in a form which is almost comparable. Admittedly, the shell construction has further advantages owing to an extremely simple introduction process. Nevertheless, however, good conditions are obtained even in the variant embodiment described here.

[0095] The surface-to-surface, positive and non-positive connection present according to the invention can be achieved, as described above, by means of surfaces of the cartridge (2) and of the holder (1) which rest against one another and which are not arranged strictly parallel to the torque of the twisting of the joint used, in particular preferably of the screw-threaded joint (see also FIGS. 3a, 3b, 4a, 4b, 5 and 6). In the context of the present invention, therefore, the non-positive engagement is preferably brought about by connecting the means (5).

[0096] It may be explicitly mentioned that, in the context of the present invention, a positive and also non-positive surface-to-surface connection in accordance with the claims is one which exists even without the application of pressure. Pressing of the cartridge onto the holder, which may be obtained by applying pressure and which, in particular, can arise in the region of purely positive regions (7a), is not comparable to an actual non-positive connection.

[0097] For all embodiments of the cartridges, it is the case that, for use as delivery, metering and mixing units, these preferably contain different components to be mixed in the individual chambers, especially components which can react with one another after being mixed or should be stored separately for other reasons. Thus, for example, masterbatches and the hardeners thereof, or low-viscosity liquids which build up a higher viscosity or thixotropy only after being mixed can be stored separately in the chambers of the cartridges. However, it is also possible to mix components of different colors, e.g. a black filler component and a white filler component in this way to give a gray mixture.

[0098] By virtue of the fact that the volumes of the chambers can be selected freely when producing the cartridges, the components to be mixed can be stored separately from one another in the quantity ratios required for subsequent use. In the case of the preferred coaxial cartridges, the volumes of the chambers are determined by means of the diameters of the tubes. For all the embodiments, it is the case that the volume flows of the components, e.g. of the masterbatch and hardener, are fed separately to the directional control valve (2.1.1) of the upper section (2.1). As a particular preference, the directional control valve (2.1.1) is a 3/2-way valve (2.1.1). In a preferred embodiment, the directional control valve (2.1.1) or 3/2-way valve (2.1.1) can also have a premixing chamber which is integrated into the directional control valve (2.1.1) and in which the initially separate volume flows of the components can meet and mix. If the directional control valve (2.1.1) is in the “metering/mixing” position, i.e. in the working position, the components, which are either in premixed form in the premixing chamber integrated into the directional control valve (2.1.1) or in largely unmixed form where there is no such premixing chamber, are fed to the actual mixing section. The extended space (2.2.1) fitted with static mixing elements (2.2.1.1) is used as a mixing section. Here, the entire space (2.2.1) can have static mixing elements (2.2.1.1). However, it is also possible, for example, for there to be a premixing section free from mixing elements and for the components, which are then premixed, to be fed to the region fitted with mixing elements only afterwards. It is equally possible to integrate the mixing elements directly from the front region of the space (2.2.1) but to embody a rear region of the space (2.2.1) without mixing elements.

[0099] The components are fed to the directional control valve (2.1.1) by means of the pistons (2.3.1), which close off the chambers from below. In this case, the pistons (2.3.1), which are pneumatically driven, force the corresponding components out of their chambers into the upper section (2.1) of the multichamber cartridge (2). During this process, the partition wall (2.2.4) between the chambers is severed by the cutting device (2.3.3) connecting the pistons (2.3.1), thereby making possible further emptying of the chambers only at this stage. In all the embodiments, the cutting device (2.3.3) connects the pistons (2.3.1) serving as the base of the chambers, thereby also ensuring that the pistons (2.3.1) are moved simultaneously when subjected to pressure and thus that the components are forced out of the chambers in the same ratio as the sizes of the chambers relative to one another, even in the case of components of widely differing viscosity, and thus in a manner independent of viscosity. Emptying therefore takes place in the volumes determined by the size of the chambers and thus in the desired proportions. After optional premixing in the premixing chamber that may be integrated into the above-described directional control valve (2.1.1) in the upper section (2.1) of the cartridge, the components are forced through the static mixing elements (2.2.1.1) and homogeneously mixed in the process.

[0100] After leaving the chambers (2.2.2) through the openings (2.2.5), the components stored in the separate chambers can thus come into contact with one another either already in a premixing chamber integrated into the directional control valve (2.1.1) of the upper section (2.1), in a section that may be present between the directional control valve (2.1.1) and the first static mixing elements (2.2.1.1) or upon contact with the static mixing elements (2.2.1.1).

[0101] In a special embodiment of the present invention, the mixing described is achieved by means of static mixing elements in the form of a mixing tube with fixed internal fittings. “Mixer rods” can preferably be used. Examples of mixer rods that are very particularly preferred can be obtained from Fluitec Georg AG (Neftenbach, Switzerland) under the name CSE-X® mixers or from Industra GmbH (Heusenstamm, Germany) under the name “mixing element” with the item number 205059 (76-104).

[0102] The cartridge holder (1) has a compressed air connection (1.2), which is preferably arranged on the base of the receiving container (1.1), and a connection (1.3) for an application device. The compressed air connection (1.2) is positioned in such a way that the compressed air which flows in during operation moves the pistons (2.3.1) serving as bases of the chambers, with the result that the components can be forced out of the chambers.

[0103] The cutting device (2.3.3) for severing the wall between two adjacent component chambers (2.2.2) is preferably designed as a wedge-shaped gap, similarly to open shears. It is thereby possible to prevent material compression during the cutting of the partition walls and, at the same time, to reduce the cutting force.

[0104] The components to be mixed transferred to the mixing section and hence to the extended space (2.2.1) must of course be fed to the application device after being mixed. This obviously takes place via the connection (1.3). Accordingly, the mixed components are fed to the connection (1.3), e.g. via an extension of the preferably cylindrical (tubular) space (2.2.1) into the lower section of the cartridge and fluid-carrying connection of said space to the connection (1.3).

[0105] Connecting the connection (1.3) on the base of the receiving shell (1.1) of the cartridge holder (1) to an application device is unproblematic and can be accomplished with all common connecting means, e.g. by means of a screw thread or quick action couplings or dovetail connections. It is also possible to integrate static mixing elements into the connection (1.3) itself and/or to position therein the static mixing elements (2.2.1.1) of the space (2.2.1), which is extended as far as the connection (1.3).

[0106] In principle, any type of application device is suitable as an application device. The application devices are used to apply the mixed components, these preferably being coating media such as paints, putties, sealing compounds or adhesives, to substrates. Thus, for example, sponges, brushes, rollers, doctor blades or nozzles of many different types, e.g. flat jet nozzles, wide jet nozzles, wide slot nozzles, multichannel (fan) nozzles or round jet nozzles, wherein the nozzles can be used with or without atomizing air. Spray guns, preferably those for the spray application of coating media compositions, are a very particularly preferred application device.

[0107] In principle, all spray guns which are used in compressed-air spraying are suitable as spray guns. Connecting the connection (1.3) on the base of the receiving container (1.1) of the cartridge holder (1) to the spray gun is unproblematic and can be accomplished with all common connections, preferably by means of a screw thread or quick action couplings or dovetail connections. Paint spray guns can be obtained from Sata GmbH & Co. KG (Kornwestheim, Germany) under the name SATAjet®, in the form of HVLP or RP spray guns, for example.

[0108] All component parts and materials of the metering and mixing device are chosen in such a way that they are designed for the occurring pressures and their envisaged function and are very largely chemically inert relative to the components to be mixed and those which have been mixed. In particular, polypropylenes are used for the walls of the chambers or extended spaces. Polyethylenes and/or composite materials are generally suitable as pistons (2.3.1), and polycarbonate and/or polyoxymethylenes are generally suitable as materials for the cutting device (2.3.3). However, the metering and mixing device and the constituent parts thereof are not restricted to these materials. Thus, it is also possible, in particular, for metals to be used, e.g. for the embodiment of the cutting device (2.3.3), or coated materials in order to make possible inert behavior relative to any chemically aggressive components, for example.

[0109] The cleaning of the metering and mixing devices according to the invention can be accomplished in a simple manner via the directional control valve (2.1.1), wherein the multichamber cartridge (2) can remain in the receiving container (1.1) during cleaning. For this purpose, the directional control valve (2.1.1) situated in the upper section (2.1) of the multichamber cartridge (2) is moved out of its “metering/mixing” operating position into the “flushing” cleaning position. In the “metering/mixing” operating position, the components can be forced out of the chambers into the directional control valve (2.1.1), while the flushing connection (4) is simultaneously shut off, whereas, in the “flushing” cleaning position, the supply of the components from the component chambers is interrupted and the central mixing channel can be connected to a flushing connection (4). Flushing is performed with a flushing medium, preferably with commercially available solvents and/or water, wherein the flushing medium can contain additional detergents and/or other typical cleaning agent additives as far as desired or required. Flushing can be performed with or without air pulses. The flushing medium should be capable of dissolving the components of the multicomponent system and any reaction products as completely as possible. During the flushing process, the flushing medium is passed through the static mixing elements in order to free these elements from the adhering component mixture and any reaction products that may already have formed. After cleaning, the multichamber cartridge (2) can be removed from the metering and mixing device without problems and stored.

[0110] The present invention also relates to a method for delivering, metering and mixing two or more components, preferably paint components, adhesive components or sealant components, particularly preferably paint components, which makes use of the metering and mixing device according to the invention.

[0111] Furthermore, the present invention relates to a method for coating substrates with two-component (2C) or multicomponent coating media using the metering and mixing device according to the invention in combination with an application device, preferably a paint spray gun. It is particularly advantageous if the method according to the invention for coating is carried out in a purely manual way. In particular, the method according to the invention is suitable for coating using small quantities of paint. The method is preferably carried out as an HVLP spraying method or as an RP spraying method. As a very particular preference, it is used in automotive refinishing. However, the abovementioned method can also be used in the context of initial OEM coating, especially during “assembly refinishing”.

[0112] In a special embodiment, the method according to the invention for coating substrates with two-component (2C) or multicomponent coating media using the metering and mixing device according to the invention in combination with an application device comprises a flushing step. In this variant of the method, the application of the 2C or multicomponent coating medium is interrupted once or several times, the multichamber cartridge (2) is cleaned during the interruption of the application, and the application is continued after the cleaning of the multichamber cartridge (2), using the same multichamber cartridge (2) or a different multichamber cartridge (2) according to the invention. During cleaning, the static mixing device, i.e. the space (2.2.1) and the mixing elements (2.2.1.1), arranged therein, of the metering and mixing device according to the invention are flushed.

[0113] If the method is carried out as an HVLP spraying method, the atomization pressure is generally 1.5 to 2 bar. In the case of RP guns, operations are generally carried out at an atomization pressure of 1.5 to 3 bar.

[0114] If two components are used, one component can be a “masterbatch”, for example, and the second component can be a hardener matched to the masterbatch. Hydroxy-functional polymers, e.g. polyhydroxy-functional poly(meth)acrylates, polyesterpolyols, polyetherpolyols, polyurethane polyols or mixed polyester/polyetherpolyols are preferably used in the masterbatches. Polythiols can also be used, for example. In the hardener components, it is customary to use polyisocyanates, such as hexamethylene diisocyanate, toluylene diisocyanate, isophorone diisocyanate or diphenylmethane diisocyanate, or the dimers, trimers and polymers of the abovementioned isocyanates, and/or aminoplast resins, e.g. melamine resins. It is likewise possible to use epoxy systems, in both conventional and aqueous form. Of course, it is also possible to use systems which become reactive only in contact with atmospheric moisture (e.g. aldimines and silanes). In general, however, it is the case that the masterbatch and the hardener contain compounds with mutually complementary functional groups. That is to say groups which enter into reaction with one another after the mixing of the two components. For example, the following complementary groups may be mentioned: amine/isocyanate, hydroxy/isocyanate, thiol/isocyanate, amine/epoxy resin/isocyanate, amine/epoxy resin, epoxy resin/anhydride, epoxy resin/carboxy, amine/anhydride, anhydride/hydroxy, hydroxy/isocyanate/amine or carbodiimide/carboxy, thiol/ene, amine/cyclocarbonate, hydroxy/cyclocarbonate, amine/hydroxy/cyclocarbonate, alpha, beta unsaturated carbonyl/amine and/or thiol, oxazoline/carboxy, silane/silane, silane/hydroxy groups. Normally, the masterbatch and the hardener react after application at temperatures of 0 to 100° C., preferably 10 to 80° C., i.e. under conventional refinish coating conditions.

[0115] In the method according to the invention, it is also possible to choose masterbatch/hardener combinations which have pot lives that are too short in a conventional procedure of premixing the components before filling the paint storage container. Even in such systems, outstanding coatings distinguished by short drying and hardening times and an outstanding appearance are obtained.