Supporting structure with varying inside diameter for pressure-free extrusion of a multicomponent compound from a coaxial cartridge

Abstract

The invention relates to a system (1) for storing and dispensing a flowable multi-component compound, comprising: - a coaxial cartridge (2) with a hollow cylindrical inner cartridge wall (4), a cartridge outer wall (5) arranged coaxially around this, an inner chamber (6) for a first component and a radially bounded outer chamber (7) for a second component of the compound located between the cartridge inner wall (4) and the cartridge outer wall (5); as well as a cartridge front wall (8) that tightly closes both chambers (6, 7) at an end face of the cartridge (2) and has a dispensing opening for each chamber; and - a support structure (3) designed to receive and hold the cartridge (2) during the dispensing of the compound and having a tubular side wall (13) for this purpose;- wherein an inner diameter of the side wall (13) is varied or adjustable in the axial and / or radial direction of the support structure (3) such that an annular gap (12) exists or can be adjusted between the cartridge outer wall (5) and the side wall (13) when inserting and removing the cartridge (2), and a close fit of the side wall (13) to the cartridge outer wall (5) during the dispensing process exists or can be adjusted.

Description

GEBIET DER ERFINDUNG

[0001] The invention relates to a system for storing and dispensing a flowable multi-component compound. It comprises a coaxial cartridge designed to receive and store a first and a second component of the compound in separate coaxial chambers, as well as a suitable support structure into which this cartridge is inserted for extruding the compound. Even though the explanation of the invention herein mostly refers only to the two coaxial chambers for two components, additional (sub-)chambers for other components of the multi-component compound can always be provided inside the cartridge.

[0002] In the prior art (see, for example, documents US 2010 / 206904; FR 2 501 080 A1 or US 2010 / 108709), various cartridge concepts are known for accommodating at least two components of flowable masses in separate chambers, which can be dispensed using a dispenser. With regard to the arrangement of the chambers, a distinction is made between coaxial cartridges and cartridges or foil containers with adjacently arranged individual cartridges or foil bags for the various components of a multi-component mass. The multi-component mass can, for example, be a sealing or fixing compound such as mortar, adhesive, and many more.

[0003] To ensure a high, consistent mixing quality of the two dispensed components, suitable support structures are usually required for the cartridges into which the cartridges are inserted during the dispensing process. These support structures absorb the pressure exerted by the cartridges during the dispensing process and prevent elastic expansion of the cartridges, which are usually made of plastic and would therefore yield to high pressure during the dispensing process without the support structure.

[0004] Due to the almost identical pressure in both chambers and the excess pressure outside the cartridge, thick-walled plastic coaxial cartridges typically exhibit elastic expansion only in the outer wall of the cartridge during the dispensing process. This can lead to undesirable pumping behavior of the cartridge, which can cause mixing problems and, consequently, inadequate curing of the compound. The elastic radial expansion of the outer wall of a thick-walled plastic cartridge during the dispensing process creates restoring forces. These forces can lead to uneven pumping behavior in the cartridge when the dispensing process is interrupted—for example, when transitioning to the next drilled hole, when several drilled holes are to be filled consecutively with the contents of the cartridge.After an interrupted dispensing process, the pressure in the outer chamber of the cartridge is released either by the component contained therein flowing out through the cartridge outlet or by the pressure on the outer piston located in this chamber being relieved. This causes a piston offset relative to the inner chamber, which leads to corresponding mixing disturbances during the subsequent dispensing process.

[0005] To counteract this, a suitable support structure must be used to prevent elastic deformation of the cartridge's outer wall during the dispensing process. This support structure must fit as tightly as possible against the cartridge to minimize the potential pumping volume: During pumping, the outer piston can only retract according to the volume of any annular gap between the support structure and the cartridge's outer wall, because the cartridge's outer wall could only expand elastically within this annular gap during the dispensing process. It is also important to ensure that the support structure is sufficiently rigid to prevent pumping due to deformation of the support structure itself.

[0006] Identical diameters (i.e., the inner diameter of the support structure is the same as the outer diameter of the cartridge) therefore offer the greatest possible protection against disruptive pumping behavior and the associated mixing disturbances of the extruded compound. However, identical diameters hinder easy insertion and removal of the cartridge into and from the support structure. This, in turn, requires a slightly larger inner diameter of the support structure compared to the outer diameter of the cartridge, i.e., the aforementioned annular gap between the cartridge and the support structure, which promotes disruptive pumping behavior. Pumping presents a major challenge, especially with large-volume cartridges and containers.

[0007] It is therefore an object of the present invention to provide a system comprising a coaxial cartridge of the type mentioned at the outset and a suitable support structure into which the cartridge is to be inserted for extruding the multi-component mass therefrom, with which both a simple insertion / removal of the cartridge is possible and the disruptive pumping behavior of the cartridge based on elastic restoring forces during the extrusion process can be prevented.

[0008] This object is achieved by a system according to claim 1. Further embodiments are specified in the dependent claims.

[0009] According to the invention, a system for storing and dispensing a flowable multi-component compound (hereinafter referred to as compound) is provided. It comprises a coaxial cartridge for storing the multi-component compound and a support structure into which the cartridge is inserted for extruding the compound. The multi-component compound comprises at least a first component and a second component, which are stored separately in the cartridge and are to be mixed with one another only upon dispensing from the cartridge. This can, in particular, be a sealing or fixing compound such as mortar, adhesive, and the like.

[0010] The cartridge comprises a hollow cylindrical inner cartridge wall and a cartridge outer wall arranged coaxially (i.e. with the same cylinder axis) around this, which outer wall is also cylindrical at least on the inside. The cartridge therefore has an inner chamber delimited radially by the cartridge inner wall for receiving the first component of the multi-component mass, and an outer chamber arranged radially between the cartridge inner wall and the cartridge outer wall for receiving the second component of the multi-component mass. Even if the following explanation of the invention and the claims mostly only refer to these two chambers for two components, further (sub-)chambers for further components of the multi-component mass can always be provided inside the cartridge, which are dispensed from the cartridge in the same squeezing process and are mixed with the first and second components.

[0011] On one of its two (in the axial direction) opposite end faces, the cartridge has a cartridge front wall which tightly closes the inner chamber and the outer chamber in the axial direction and has a dispensing opening for the first component in the area of ​​the inner chamber and a dispensing opening for the second component in the area of ​​the outer chamber.

[0012] In particular, the cartridge further comprises an inner piston that closes the inner chamber at the rear (i.e., toward the other end of the cartridge) and is axially movable therein, as well as an outer piston that also closes the outer chamber at the rear and is axially movable therein. The inner piston is configured to extrude the first component from the inner chamber, and the outer piston is configured to extrude the second component from the outer chamber by simultaneously axially moving both pistons toward the cartridge front wall (this is referred to herein as the extrusion process).

[0013] For this squeezing process, the system comprises a support structure which is designed to receive and hold the cartridge during the squeezing of the mass therefrom and for this purpose has an at least partially tubular section-shaped side wall which is at least partially closed on its first end face by a support structure front wall designed to support the cartridge front wall. This side wall is designed so as to be variable or adjustable in its inner diameter in the axial and / or radial direction of the support structure (i.e., variable by a suitable force applied within the system or from the outside) in such a way that an annular gap (i.e., play) exists or is adjustable between the cartridge outer wall and the side wall when inserting and removing the cartridge into / from the support structure, and a close fit of the side wall against the cartridge outer wall (i.e.,without the aforementioned annular gap in between) for the duration of an ejection process or is adjustable. This support structure can thus simultaneously enable both easy insertion / removal of the cartridge and a tight fit against it during ejection, thus avoiding the disruptive pumping behavior (i.e., elastic recovery behavior) of the cartridge described above.

[0014] In the following, some different design options are shown to make the annular gap between the cartridge and the support structure variable in this way: According to the invention, the outer wall of the cartridge is also cylindrical on the outside (cf. Fig. 1 ). The side wall of the support structure is designed as a cylindrical tube slotted in the axial direction, in particular made of elastically deformable material (e.g. steel). The support structure also has an externally actuatable closing and opening mechanism for this slot, such that when the slot is open, the tube has an inner diameter that is larger than the outer diameter of the cartridge outer wall by a predetermined twice the annular gap width, whereas when the slot is closed, the tube lies closely against the cartridge outer wall. Thus, when its closing and opening mechanism is closed, the support structure lies completely against the cartridge, pumping of the cartridge when pressurized is prevented, and the compound can be squeezed out. The aforementioned predetermined annular gap width can, for example, be just large enough to enable the cartridge to be inserted and removed smoothly from the support structure.

[0015] In particular, the closing and opening mechanism for the slot can be designed as a wedge system (cf. Fig. 2-4 ). This comprises an axially slotted inner wedge made up of two wedge halves that are attached to the outside of the pipe on either side of its slot and taper in a wedge shape in the axial direction of the pipe. The wedge system also comprises an outer wedge that surrounds the inner wedge on the outside and can be moved axially thereon, with two opposite wedge-shaped inner flanks facing the inner wedge. The wedge-shaped inner flanks of the outer wedge are designed in such a way that when the outer wedge is moved axially in one direction, they push the two wedge halves of the inner wedge towards each other in the circumferential direction until the slot in the pipe closes. By axially moving the outer wedge in the other direction, the inner wedge, and with it the slot in the pipe, can be opened again.

[0016] In particular, in this embodiment, the support structure can have an integrated lid that can be adjusted between an open state for inserting and removing the cartridge and a closed state for holding the cartridge in the support structure and performing an ejection process. The closing and opening mechanism for the slot can be mechanically coupled to the lid, such that the slot is also open when the lid is open, and the slot is also closed when the lid is closed.

[0017] According to a second disclosed but not claimed embodiment, the cartridge outer wall is conical on the outside and tapers towards the cartridge front wall with a predetermined conical pitch (cf. Fig. 5a-5b ). The side wall of the support structure also tapers conically on the inside towards the support structure front wall with the same cone pitch as the cartridge outer wall and has the same inner diameter on the support structure front wall as an outer diameter of the cartridge outer wall on the cartridge front wall. Due to this geometry, an annular gap exists between the cartridge outer wall and the side wall when the cartridge is inserted into the support structure and removed from it. This annular gap only closes completely when the cartridge front wall comes into contact with the support structure front wall. Here too, the support structure lies completely against the cartridge for the extrusion process, so that the compound can be extruded without any disruptive resilience of the cartridge outer wall.

[0018] In particular, in this embodiment, the support structure can be opened and closed again along an axial dividing line in its side wall in order to remove the cartridge inserted therein (cf. Fig. 6 ). For this purpose, it can have two sidewall segments that can be reversibly separated from one another along this axial dividing line, each extending only over a partial angle segment in the circumferential direction and being rotatably connected to one another, for example, via an axial hinge or other pivot joint along an axial connecting line that lies circumferentially away from the dividing line. This can also be used to further simplify the insertion of the cartridge into the support structure.

[0019] According to a third disclosed but not claimed embodiment, the cartridge outer wall is conical on the outside and widens towards the cartridge front wall with a predetermined conical pitch (cf. Fig. 7 ). The support structure front wall is designed as a reversibly closable lid for opening the support structure to insert the cartridge over the first end face of the support structure and for closing the support structure for the duration of an ejection process. The side wall of the support structure consists of a cylindrical outer tube and an inner tube inserted into this and mounted axially displaceably therein. The inner tube widens conically on the inside towards the support structure front wall with the same cone pitch as the cartridge outer wall and has the same inner diameter at the support structure front wall as an outer diameter of the cartridge outer wall at the cartridge front wall. The support structure has an axial pressure device on its second end face (for example in the form of a spring which loads the inner tube with spring force in the axial direction), which is designed to press the inner tube against the closed lid.Thus, the support structure for the squeezing process is completely attached to the cartridge, so that the mass can be pressed out without any disturbing recovery behavior of the cartridge's outer wall.

[0020] According to a fourth disclosed but unclaimed embodiment, the cartridge outer wall is also cylindrical on the outside. The side wall of the support structure is composed of an outer tube, which tapers conically on the inside towards the support structure front wall with a predetermined conical pitch, and an inner tube which is mounted axially displaceably (and in particular is completely removable) therein, which is cylindrical on the inside and has multiple axial slots to change its diameter. (The aforementioned outer tube geometry can, for example, be achieved for manufacturing or stability reasons by a suitable conical tubular inner layer which is permanently fastened in a stable cylindrical outer tube, for example as in Fig. 8 .)

[0021] The inner tube tapers conically on the outside towards the support structure front wall with the same cone pitch as the outer tube. When it rests against the support structure front wall, it has completely closed slots and the same inner diameter as the outer diameter of the cartridge outer wall. The support structure has an axial pressure device on its second end face (for example, in the form of a spring that loads the inner tube with spring force in the axial direction), which is designed to press the inner tube against the support structure front wall. Thus, the support structure also rests completely against the cartridge for the extrusion process, allowing the compound to be extruded without disruptive recovery behavior of the cartridge outer wall.

[0022] In particular, in this embodiment, the inner tube can have radially inwardly projecting driving hooks on the second end face of the support structure, which are arranged axially behind the outer bulb of the cartridge inserted in the support structure (cf. Fig. 8 The drive hooks extend radially behind the outer piston, so that when the outer piston is retracted after the extrusion process to remove the cartridge, it takes the inner tube of the support structure along with it via the drive hooks and pulls it out of the outer tube. This simultaneously opens the slots in the inner tube, creating an annular gap between the outer wall of the cartridge and the side wall of the support structure, facilitating removal.

[0023] According to a fifth disclosed but not claimed embodiment, the cartridge outer wall is also cylindrical on the outside. The side wall of the support structure is composed of a cylindrical outer tube, a plurality of outer rings mounted axially displaceably therein, which in axial cross-section each taper inwards in a trapezoidal or triangular manner (i.e. towards the cylinder axis) and with their wide sides resting on an inner side of the outer tube, as well as a plurality of inner rings arranged alternately with the outer rings in the axial direction, which partially project radially between the outer rings and in the axial cross-section each widen inwards in a trapezoidal or triangular manner (cf. Fig. 9 ). Each inner ring has several radial cuts or notches distributed around its circumference to change its diameter (see Fig. 10 ), so that it can be pressed radially inward by axially pushing the adjacent outer rings together, and its inner diameter can thus be reduced to the same size as the outer diameter of the cartridge outer wall, so that it is pressed against the outer wall of the cartridge inserted in the support structure. For this purpose, the support structure has an axial pressure device on its second end face (for example in the form of a spring that loads the outer rings with spring force in the axial direction), which is designed to axially push the outer rings together towards the front wall of the support structure.

[0024] In particular, the inner rings can be geometrically designed on their wide inner sides facing the cartridge in such a way that they complement the geometry of the cartridge outer wall and can be geometrically designed for the aforementioned interaction with the outer rings in such a way that when they rest against the cartridge outer wall they completely cover it and thus provide radial support over its entire surface during the squeezing process.

[0025] According to a sixth disclosed but unclaimed embodiment, the cartridge outer wall is also cylindrical on the outside. The side wall of the support structure is composed of a cylindrical outer tube and a hydraulic cushion, which is in contact with the outer tube over its entire radial circumference and at least partially also with the support structure front wall, and is filled with a flowable medium (cf. Fig. 11 ).

[0026] The hydraulic cushion is designed and dimensioned such that, when the cartridge is inserted into the support structure, it encloses the entire outer wall and at least part of the cartridge front wall. In its unloaded state, which prevails before and during insertion of the cartridge into the support structure, its inner diameter is larger than the outer diameter of the cartridge's outer wall by a predetermined twice the annular gap width. In contrast, in its loaded state, which occurs with the start of an extrusion process and the associated pressing of the cartridge's outer wall against the support structure's front wall, the cushion comes to rest tightly against the entire outer wall of the cartridge due to the immediate escape / displacement of the flowable medium from the front wall sections into the side wall sections of the cushion.Thus, the support structure for the dispensing process fits completely against the cartridge, allowing the compound to be pressed out without disruptive rebound behavior of the cartridge's outer wall. The predetermined annular gap width can, for example, be large enough to allow the cartridge to be inserted and removed smoothly from the support structure.

[0027] In particular, the flowable medium can be largely incompressible, at least at pressures that can be achieved during a pressing process in the system, so that when the cartridge outer wall is pressed against the support structure front wall, it is displaced from the front wall sections into the side wall sections of the cushion right at the beginning of the pressing process until the annular gap remaining between the cushion and the cartridge outer wall closes. A gel or a liquid, for example, can be suitable as a flowable medium for this purpose. In principle, however, certain gases can also be suitable for the described functionality. Although they are compressible, they can quickly escape into the side wall sections when the pressure in the front wall sections of the cushion increases, thereby also causing them to swell radially.

[0028] In this case, the cartridge inner wall and the cartridge outer wall can each have a circular cross-section. However, this is not absolutely necessary for the functional principle described here, so other cross-sectional shapes, such as elliptical or rectangular, can also be implemented.

[0029] At least the inner and / or outer walls of the cartridge can be made of plastic. In particular, the entire cartridge can be made of plastic, with its individual components being made of the same or different types of plastic. However, other materials, such as metal, can also be used. The same can also apply to the support structure.

[0030] In a specific embodiment, the cartridge front wall has a connecting piece on its side facing away from the inner and outer chambers, into which the discharge openings of the inner and outer chambers respectively open and which is designed to connect a mixer for mixing the various components of the multi-component mass during the dispensing process.

[0031] The above aspects of the invention and their embodiments and specific configurations are further explained below with reference to examples illustrated in the drawings. The drawings are schematic. They may, but do not have to, be to scale. They show: Figure 1 shows a longitudinal section of a system according to the invention; Figure 2 shows a perspective view of a slotted support structure of the system of the Fig. 1 with a wedge lock with the slot open; Figure 3 shows a half radial cross-section of the support structure of the Fig. 2 with the wedge lock with the slot open; Figure 4 axial side view of the support structure of the Fig. 2 with a view of the wedge closure with the slot open and closed; Figure 5a-b shows a longitudinal section of a system according to a second disclosed but not claimed embodiment of the invention with an annular gap between the cartridge and the support structure when inserting the cartridge (a) and without an annular gap when the cartridge is fully inserted (b); Figure 6 shows a cross section of the system of Fig. 5a-b with a side wall of the support structure open along an axial dividing line; Figure 7 shows a longitudinal section of a system according to a third disclosed but not claimed embodiment of the invention; Figure 8 shows a longitudinal section of a system according to a fourth disclosed but not claimed embodiment of the invention; Figure 9 shows a longitudinal section of a system according to a fifth disclosed but not claimed embodiment of the invention; Figure 10 shows a radial cross section of an inner ring of the support structure of the Fig. 9 ; and Figure 11 shows a longitudinal section of a system according to a sixth disclosed but unclaimed embodiment of the invention.

[0032] Fig. 1 shows in an axial longitudinal section an example of a system 1 according to the invention, in which a coaxial cartridge 2 for extruding the multi-component mass contained therein is inserted into a support structure 3, the side wall 13 of which is designed as a one-piece slotted tube with an axial slot 14 (which is only visible in the views of the Fig. 2 bis 4 can be seen) and a wedge lock (wedge system) as a closing and opening mechanism (cf. Fig. 2-4 ) for the slot 14.

[0033] The cartridge 2 comprises a hollow cylindrical cartridge inner wall 4 and a hollow cylindrical cartridge outer wall 5 arranged around it with a common cylinder axis A, whereby an inner chamber 6 radially delimited by the cartridge inner wall 4 and an outer chamber 7 arranged radially between the cartridge inner wall 4 and the cartridge outer wall 5 are formed. A first component of the multi-component mass to be dispensed is accommodated in the inner chamber 6, while a second component of the multi-component mass is accommodated in the outer chamber 7 (not shown).

[0034] At the Fig. 1 On the right-hand side of the first end face of the cartridge 2, its cartridge front wall 8 closes the inner chamber 6 and the outer chamber 7, with one dispensing opening per chamber being formed in the cartridge front wall 8. The two dispensing openings open into a connecting piece 9, which is formed in the cartridge front wall 8 on the side facing away from the inner and outer chambers 6, 7 and is designed for connecting (e.g. by placing or screwing on) a mixer (not shown) for mixing the first and second components of the multi-component mass during the dispensing process.

[0035] Furthermore, the cartridge 2 comprises an inner piston 10 closing the inner chamber 6 at the rear and axially movable therein, and an outer piston 11 closing the outer chamber 7 at the rear and axially movable therein, by their simultaneous axial movement in Fig. 1 to the right, the multi-component mass can be pressed out of the cartridge 2 through the dispensing openings of the cartridge front wall 8 (pressing process). The support structure 3 is Fig. 1 The first end face on the right is closed by a support structure front wall 15, which in this example is formed integrally with the side wall 13 (with the exception of an opening through which the connecting piece 9 of the cartridge 2 protrudes outwards). The support structure front wall 15 serves to support the cartridge front wall 8 during the squeezing process.

[0036] As in Fig. 1 shown, an inner diameter of the support structure 3 with the slot 14 open (in Fig. 2-4 shown) by a predetermined double annular gap width greater than an outer diameter of the cartridge 2, so that a cylindrical annular gap 12 remains between the cartridge outer wall 5 and the side wall 13 of the support structure 3, which facilitates the insertion of the cartridge 5 into the support structure 3.

[0037] In order to make the annular gap 12 variable, the side wall 13 of the support structure 3 is Fig. 1 as a slotted cylindrical tube, preferably made of an elastically deformable material (e.g. steel). The spring-loaded state according to Fig. 1 opened axial slot 14 is in the longitudinal section of the Fig. 1 not visible and is subsequently explained using Figuren 2-4 explains: Fig. 2 bis 4 show the slot 14 and its closing and opening mechanism, designed purely as an example as a wedge system, in three different views. Fig. 2 the support structure 3 of the Fig. 1 in a perspective view, Fig. 3 in half a radial cross-section and Fig. 4 in a side view with a view of the slot 14 and the wedge system.

[0038] The slot 14 extends in the longitudinal direction of the pipe. The width of the slot 14, for example, is approximately 5 mm, which is sufficient for a pipe diameter of approximately 113 mm. The slot width should be selected appropriately according to the pipe diameter to ensure a sufficient annular gap 12 for inserting / removing the cartridge 2, as well as sufficient travel for clamping the support structure 3, and to enable the support structure 3 to fit tightly against the cartridge 2 during the ejection process.

[0039] The closing and opening of the slot 14 by clamping the one-piece, slotted tube can be made possible by means of a wedge system comprising an inner wedge 16, which is also slotted and is fastened to the tube and consists of two wedge halves 16a and 16b extending axially on both sides of the slot 14, and an outer wedge 17 with wedge-shaped inner flanks 17a and 17b, which is axially displaceable on the inner wedge 16 and encloses the two wedge halves 16a and 16b.

[0040] If the outer wedge 17 is pushed back in the axial direction, the slotted tube opens due to the spring action of its material. The annular gap 12 ( Fig. 1 ) is thus ensured. If the enclosing outer wedge 17 is pushed onto the two underlying wedge halves 16a and 16b of the inner wedge 16, the gap 14 in the side wall 13 closes, and the annular gap 12 of the Fig. 1 is eliminated. This allows a firm enclosing of the support structure 3 around the cartridge 2. The described open and closed positions of all elements involved are shown in Fig. 4 each indicated by dashed lines.

[0041] According to a particularly advantageous specific embodiment of the system 1, the movement of the enclosing outer wedge 17 is coupled to the closing of a lid (not separately shown) on the dispensing device (i.e. support structure 3), which lid is provided for the reversible opening of the support structure for inserting and removing the cartridge 2. When this lid is opened, an annular gap 12 is formed between the cartridge 2 and the support structure 3 and the cartridge 2 can be inserted. When the lid is closed, the enclosing outer wedge 17 is pulled over the support structure 3, and the annular gap 12 closes as a result. The support structure 3 thus lies completely against the cartridge 2, pumping of the cartridge 2 when pressure is applied is prevented and the mass can be pressed out.

[0042] In the following description of further examples of System 1 of the type presented herein using the Figuren 5a-11 will only point out the differences to the Fig. 1-4 described first embodiment. Otherwise, the same applies to the cartridge 2 and the support structure 3 as described above with reference to Fig. 1 described.

[0043] Figur 5a-5b each show a longitudinal section of a system 1 according to a second disclosed but not claimed embodiment of the invention with an annular gap 12 between cartridge 2 and support structure 3 during insertion or removal of the cartridge 2 ( Fig. 5a ) and without annular gap 12 with the fully inserted cartridge 2 ( Fig. 5b ). A convenient insertion and removal of the cartridge 2 with simultaneous elimination of the annular gap 12 when the cartridge 2 is inserted can be achieved here by an externally conical design of the cartridge 2 and an internally conical design of the support structure 3 with as precisely the same cone pitch as possible.

[0044] The cartridge 2 tapers towards the front through a conical outer wall (i.e. towards the cartridge front wall 8). The support structure 3 has the same geometric design and also tapers towards the front (i.e. towards the support structure front wall 15). The angles of the cartridge outer wall 5 and the side wall 13 of the support structure 3 are identical. The cartridge inner wall 4 can remain cylindrical and does not require any conical design. However, loading the dispensing device (support structure 3) from the front is not possible in this case. The cartridge 2 can instead be inserted axially from the rear or from the side into a Fig. 6 sketched two-part support structure 3. Dividing the conically shaped side wall 13 into two parts offers the advantage that the cartridge 2 can be removed more easily after it has been pressurized (ie after the squeezing process).

[0045] Fig. 6 shows a cross-section of system 1 of the Fig. 5a-b with a side wall 13 of the support structure 3 open along an axial dividing line 18. For this purpose, the side wall 13 has two side wall segments 13a and 13b which can be separated from one another in a reversible manner along the axial dividing line 18 and which are rotatably connected to one another along an axial connecting line 19 (for example in the form of a hinge) which lies away from the dividing line 18 in the circumferential direction.

[0046] Fig. 7 shows a longitudinal section of a system 1 according to a third disclosed but not claimed embodiment of the invention. To ensure insertion of the cartridge 2 from the front, the cartridge 2 tapers here, in contrast to Fig. 5a-5b backwards, not forwards. For this purpose, the side wall 13 of the support structure 3 has a movable conical element in the form of a conical inner tube 20, which is inserted into a cylindrical outer tube 21. The inner tube 20 is loaded by means of an axial pressure device 30 in the form of springs arranged on the second end face of the support structure 3 and is mounted in the outer tube 21 for axial displacement.

[0047] If contact occurs between the cartridge 2 and the conical inner tube 20, the entire structure slides further into the enclosing support structure 3 until the cartridge front wall 8 is flush with the side wall 13 of the support structure 3 and the support structure front wall 15 can be closed in the form of a lid. With this embodiment, the influence of any diameter tolerances in the cartridge 2 or the support structure 3 can be reduced or eliminated. The removal of the empty cartridge 2 can be assisted by the pistons 10 / 11 of the cartridge 2 or the dispensing device, which push the empty cartridge 2 forward out of the enclosing cone of the inner tube 20 with the support structure front wall 15 (lid) open.

[0048] Fig. 8 shows a longitudinal section of a system 1 according to a fourth disclosed but unclaimed embodiment of the invention. In order to dispense with a conical design of the cartridge 2, two conical elements are provided in the side wall 13 of the support structure 3: a conical outer tube 22 and a conical inner tube 23. In this example, the conical outer tube 22 is composed of a cylindrical outer tube 22a and a tubular inner layer 22b, which is firmly connected to the outer tube and tapers conically towards the front and cannot move axially or radially with respect to the cylindrical outer tube 22a.

[0049] The movable conical inner tube 23, which surrounds the cartridge 2, is axially slit several times (not shown) to allow its diameter to be changed so that it fits tightly against the cartridge 2 during the dispensing process. It is also mounted axially movable on the inside of the conical outer tube 22 and is provided with an axial pressure device 30 (similar to Fig. 7 ) spring-loaded in order to support the cartridge 2 over its entire surface when it is inserted. In order to insert and remove the cartridge 2, the pistons 10 / 11 of the cartridge 2 or of the dispensing device can retract the conical inner tube 23 using its radially and axially engaging hooks 24 behind the piston 11 during the return travel of the pistons 10 / 11 and thus create an annular gap 12 similar to the Fig. 1 When the pistons 10 / 11 advance, they release the axial movement of the conical inner tube 23 and the springs of the axial pressure device 30 press the inner tube 23 into the cone of the outer tube 22. In the process, the diameter of the multi-slotted inner tube 23 narrows, whereby it contacts the cartridge 2 and the annular gap 12 is eliminated, as shown in Fig. 8 shown.

[0050] Fig. 9 shows a longitudinal section of a system 1 according to a fifth disclosed, but not claimed, embodiment of the invention. It shows a further possibility of a conical design of the side wall 13 of the support structure 3 in a cylindrical cartridge 2 by the use of many conical inner rings 25, which are formed by suitable separation in the radial direction (for example, by radial incisions 33 as in Fig. 10 ) are variable in diameter. An axial force F, which is applied, for example, by springs of an axial pressure device 30 as in Fig. 7 or 8 can be effected, presses the conical inner rings 25 with their surfaces 26 which are conical on both sides in the axial direction against adjacent outer rings 27, which also have surfaces 28 which are conical on both sides in the axial direction and in this case rest with their wide sides 29 on a cylindrical outer tube 31 of the support structure 3, on which they are mounted so as to be axially displaceable.

[0051] The axial force F pushes the outer rings 27 axially together, whereby the intermediate inner rings 25 are pressed inward by the interaction of the conical surfaces 26 and 28 (as illustrated by radial arrows). This simultaneously causes a reversible diameter reduction of the inner rings 25 by the elastic closure of their radial notches 33 ( Fig. 10 ). The inner rings 25 consequently rest with their wide inner sides 32 against the cartridge 2 and eliminate the annular gap 12 ( Fig. 1 ). When the axial force F is removed, the spring action of the radial incisions 33 of the inner rings 25 increases their diameter, and an annular gap 12 is created again between the support structure 3 and the cartridge outer wall 5 (cf. Fig. 1 ). This allows for easy insertion or removal of cartridge 2.

[0052] Fig. 10 shows a radial cross section of an inner ring 25 of the support structure 3 of the Fig. 9 . Shown in an exemplary uniform distribution of radial incisions 33, which enable an elastic change in the diameter of the inner ring 25. For this purpose, in this example, numerous radial incisions 33 are provided alternately on the outside and inside of the inner ring 25, each of which only divides the inner ring 25 to approximately half its radial thickness or only partially beyond.

[0053] Fig. 11 shows a longitudinal section of a system 1 according to a sixth disclosed but unclaimed embodiment of the invention, which illustrates a further embodiment of a support structure 3 with a variable inner diameter in a cylindrically designed cartridge outer wall 5. Here, the inner diameter of the side wall 13 of the support structure varies by hydraulic action. For this purpose, the side wall 13 comprises a cylindrical outer tube 31, inside which a hydraulic cushion 34 is inserted, which encloses the cartridge 2 both around the circumference and on the front contact surface (i.e. on the cartridge front wall 8). If pressure is applied from behind to the pistons 10 / 11 located in the cartridge 2, the cartridge 2 presses against the front wall section 35 of the hydraulic cushion with a contact force F1 equal to the dispensing force provided by the dispensing device.The flowable medium in the cushion 34 is displaced into the rear side wall section 36 of the cushion 34, i.e., the section encompassing the outer wall 5 of the cartridge, whereby its thickness increases radially inward and the inner diameter decreases accordingly, so that the cushion 34 comes into full contact with the cartridge 2 and exerts a radial pressure on it, indicated by arrows. Thus, the annular gap 12 (cf. ) prevailing in the unloaded state of the system 1 closes. Fig. 1 ), so that expansion of the cartridge 2 under pressure is prevented.

Claims

1. System (1) for storing and discharging a flowable multi-component composition, comprising: - a coaxial cartridge (2) having a hollow-cylindrical cartridge inner wall (4), and a cartridge outer wall (5) which is arranged coaxially around said inner wall and is cylindrical at least on the inside, and having an inner chamber (6) for a first component that is delimited radially by the cartridge inner wall (4), and an outer chamber (7) for a second component of the composition that lies radially between the cartridge inner wall (4) and the cartridge outer wall (5), as well as having a cartridge front wall (8) which firmly closes the two chambers (6, 7) on an end face of the cartridge (2) and has a discharging opening in each chamber; and - a support structure (3) which is designed to receive and hold the cartridge (2) when the composition is pressed out of said cartridge and for this purpose has a side wall (13) which is shaped at least partly like a tube portion and is at least partly closed on its first end face by a support structure front wall (15) designed to support the cartridge front wall (8); - wherein an inner diameter of the side wall (13) is varied or can be adjusted in the axial and / or radial direction of the support structure (3) in such a way that an annular gap (12) between the cartridge outer wall (5) and the side wall (13) is created or can be adjusted when the cartridge (2) is inserted into and removed from the support structure (3), and a tight fit of the side wall (13) against the cartridge outer wall (5) is created or can be adjusted over the duration of a pressing-out process, characterized in that the cartridge outer wall (5) is also cylindrical on the outside; - the side wall (13) of the support structure (3) is designed as a cylindrical tube which is slit in the axial direction; and - the support structure (3) has an externally operable closing and opening mechanism for this slit (14) such that, when the slit (14) is open, the tube has an inner diameter which is larger than an outer diameter of the cartridge outer wall (5) by a predetermined double annular gap width, while, when the slit (14) is closed, the tube fits tightly against the cartridge outer wall (5).

2. System (1) according to claim 1, wherein - the cartridge (2) also has an inner piston (10) which closes the inner chamber (6) at the rear and can be moved axially in said inner chamber, and an outer piston (11) which closes the outer chamber (7) at the rear and can be moved axially in said outer chamber; and - the inner piston (10) is designed to press the first component out of the inner chamber (6) and the outer piston (11) is designed to press the second component out of the outer chamber (7) by means of a simultaneous axial movement of the two pistons (10, 11) toward the cartridge front wall (8) in the support structure (3).

3. System (1) according to any of the preceding claims, wherein - the closing and opening mechanism for the slit (14) is designed as a wedge system, comprising: - an axially slit inner wedge (16) which consists of two wedge halves (16a, 16b) which are attached on the outside to the tube on both sides of its slit (14) and taper in a wedge shape in the axial direction of the tube; and - an outer wedge (17) which encloses the inner wedge (16) on the outside, can be shifted axially on said inner wedge and has two opposite wedge-shaped inner flanks (17a, 17b) which face the inner wedge (16) and, when the outer wedge (17) is axially shifted in one direction, push the two wedge halves (16a, 16b) of the inner wedge (16) toward one another in the circumferential direction until the slit (14) in the tube closes as a result, while the axial shifting of the outer wedge (17) in the other direction allows the inner wedge (16), and with it the slit (14) in the tube, to open again.

4. System (1) according to any of the preceding claims, wherein - the support structure (3) has an integrated cover which can be adjusted between an open state, which is designed for inserting the cartridge (2) into the support structure (3) and for removing the cartridge (2) from the support structure (3), and a closed state, which is designed for holding the cartridge (2) in the support structure (3) and for carrying out a pressing-out process; and - the closing and opening mechanism for the slit (14) is mechanically coupled to the cover in such a way that when the cover is open, the slit (14) is also open and when the cover is closed, the slit (14) is also closed.

Images