WO2007122001A1

WO2007122001A1 - Aerosol can with inner sleeve

Info

Publication number: WO2007122001A1
Application number: PCT/EP2007/003636
Authority: WO
Inventors: Mihály RIDEG
Original assignee: FAZEKAS, Gábor; Werner, Hans Jürgen
Priority date: 2006-04-25
Filing date: 2007-04-25
Publication date: 2007-11-01
Also published as: DE102006056280A1; EP2013115B9; ATE533704T1; EP2013115A1; EP2013115B1; PL2013115T3

Abstract

The invention relates to an aerosol can (1), comprising a body (2), a valve arranged in a dome, a base (3), an inner sleeve (5) arranged on the base (3), the inner sleeve (5) being provided with a cylindrical sleeve wall (6), a seal (7), a base element (8) and a pin (9), arranged in a displaceable manner within the inner sleeve (5) with the end (9f) thereof extending through the base element (8), the base element (8) comprising a guide element (10) for the pin (9) and a retainer piece (11) running through and fixed to the base (3) of the aerosol can (1), the pin (9) cooperating with a trigger element (20) arranged outside the aerosol can. The inner sleeve (5) comprises at least one flexible zone for pressure equalisation between the can interior and the interior of the sleeve.

Description

Pressure cell with inner sleeve

The invention relates to a pressure box with a frame, a valve disposed in a dome, a bottom and an inner sleeve disposed on the bottom, wherein the inner sleeve a cylindrical sleeve wall, a closure, a bottom element and a slidably disposed in the inner sleeve and with its end through the bottom element protruding plunger has lo and the bottom element a guide for the plunger and a holding part, which is guided through the bottom of the pressure cell and fixed thereto. The plunger cooperates with a release element arranged outside the pressure box.

In particular, the invention relates to pressurized cans for two-component aerosol systems, as used, for example, for two-component assembly foam systems. Such pressure cans, in addition to the main component, which is required for producing and applying polyurethane foams or paints, in the inner sleeve, a second component, which reacts with the main component to the finished product, the actual foam or paint, 2o. Equally, however, the invention can also be used for other two-component formulations, for example in surface technology and for adhesives.

The substances contained in the pressure vessels are usually liquid and consist of a prepolymer, conventional additives and under pressure

25 liquid propellant, which is required for discharging the contents of the pressure vessel and as a foaming agent. The other component is in one Inner sleeve is present in a relatively small amount and usually consists of a fast-reacting with the main component compound in polyurethane prepolymers with reactive isocyanate groups, for example, a crosslinker in the form of a hydroxy compound or an amine, optionally together with catalysts. The component in the inner sleeve is used to influence the curing and quality of the product, usually to accelerate the curing. The second component is introduced shortly before the application of the can content by opening the inner container in the pressure cell and mixed by shaking it. The finished mixture must then be applied within a defined time to prevent the curing of the prepolymer in the can.

From DE 82 27 229 U a pressure cell with a formed by forming a metal molded part one-piece bottom is known in which in a recess of the externally threaded neck of an additional container is inserted and with the help of a nut screwed from the outside under deformation of a O-ring seal between a shoulder of the additional container and the inner edge of the bottom recess is braced. The guided in turn by a piston-shaped seal in the interior of the additional container and sealed rod is designed as a shaft which rotates in the Zusatzbehälterhals and is supported inside on this. If the shaft is driven from the outside, this leads to the positive engagement of its inner end with the lid of the additional container, which is thereby pressed against the internal pressure in the outer space of the can.

The starting point of the invention is WO 85/00157 A1, which describes a pressure cell for dispensing two-component foaming agents. Inside this pressure box, a second component receiving additional container is arranged. The auxiliary container has a lid which can be blasted over a guided through the bottom of the pressure cell into the interior of the additional container rod. The rod is movably mounted within the additional container and guided by a seal arranged in the bottom plate of the can bottom. Both pressure sockets according to the prior art require a relatively complex construction or assembly. In this case, the container suffers according to DE 82 27 229 U under the relatively complicated mechanics. Although the breaking off of the lid against the relatively large internal pressure of the container is forced by the rotational movement of the rod, this is relatively laborious and requires a great deal of effort for the sealing system.

Although the pressure cell according to WO 85/00157 A1 has proven itself overall and represents a significant improvement over the said utility model, however, the introduction of the rod is problematic due to the rubber seal in the sickle plate and requires a non-optimal geometry of the rod.

In addition to the elaborate production and assembly, both pressure sockets according to the prior art system-related sealing problems, which is based on the - after filling with propellant gas - automatically building pressure difference between the outer space and the inner sleeve. This also contributes to the fact that the inner sleeve can not be filled without air and sealed. During the storage life of the can, which may well be several months, this pressure difference is essentially due to the fact that the outer prepolymer penetrates into the inner sleeve. While slow, this process is small in volume and does not interfere with the actual chemical reaction that leads to curing. However, a problem is the reaction product, which deposits in the area of the seals and in particular in the area of the lid and leads to sticking and hardening. These hardenings can cause the valve to clog or the pressure box will not properly close again after the first spray and become unusable. In addition, the resulting particles in the case of a two-component paint spray for the quality of the paint coating produced therewith are disadvantageous.

According to DE 10 2004 024 777 A1, the cover of the inner sleeve of a 2K pressure cell is hydraulically blasted off. For this purpose, the inner sleeve contents is pressurized with a stamp from the outside, whereby the pressure through the

Inner sleeve space propagates towards the lid and peels it off. The The problem of the pressure difference between inner tube content and outer space content is solved by allowing the outer space content to enter the space of the inner sleeve below the stamp and to provide pressure equalization via the plunger. However, hardening reactions which also take place here on the lid and stamp lead to a bond which, after a certain storage time, makes it difficult or impossible to break off the lid.

Finally, multi-component pressure cans are known in which the inner sleeve is made of metal and sealed with an integral metal membrane. These inner sleeves are expensive to manufacture.

Another problem that arises with the multicomponent pressure cans described above and numerous variants thereof is the reliable removal of the cover or closure of the inner sleeve. In almost all variants, it can happen that the closure dissolves only inadequately from the sleeve wall and, after the solution, rests again on the inner sleeve opening like a flap attached to a hinge. In this case, there is only an incomplete mixing of the contents of the inner sleeve with the main component located in the outer space, which is at best disadvantageous for the product quality.

The invention is therefore the object of the pressure can according to WO 85/00157 A1 so educate that can easily mount the parts of the inner sleeve to a captive and absolutely tight unit. In addition, the sealing problem occurring between the outer space of the pressure cell and the inner sleeve due to the pressure difference which is necessary to be adjusted should be defused and finally a reliable separation of the closure of the inner sleeve should be achieved.

This object is achieved with a pressure cell of the type mentioned above in that the inner sleeve (5) has at least one yielding zone for pressure equalization between the can interior and sleeve interior.

Apart from the inner sleeve, the pressure cell according to the invention is made more or less conventional. The pressure cell has a frame, a in a dome arranged valve and a bottom on which the externally releasable inner sleeve is arranged. Such cans are made of tinplate or aluminum; in tinplate cans the can bottom is crimped to the frame and usually still has a central bottom plate which receives the inner sleeve, aluminum cans frame and bottom are made in one piece, wherein the inner sleeve is fixed in a central recess of the bottom.

In the context of the description, the term "closure side" is understood to mean that side of a part which faces the inner container closure. "Bottom-side" is accordingly that end which points away from the closure side. In general, therefore, "bottom side" refers to the end of a part that faces the bottom of the can, but only as long as this part or end is inside the pressure cell.

An essential element for the maintenance of the functionality of the inner sleeve is their equipment with a yielding membrane, which - after filling the inner sleeve with the second component under atmospheric pressure - ensures that the pressure difference between the interior of the inner sleeve and the inner space of the pressure cell, which substantially the filling with the propellant gas is determined is compensated. As mentioned above, the filling of the inner sleeve with the second component is never 100%; There is always a certain amount of compressible gas. The elastic membrane or film is suitable to yield under the pressure of the propellant gas in the pressure can interior and to bring about pressure equalization.

In the simplest embodiment, this yielding zone is an elastically formed wall segment which is characterized, for example, by a significantly smaller wall thickness. For this purpose, the wall may preferably have a window, which is sealed with an elastic film or membrane. Suitable for this example are plastic films, including metallized plastic films. Such plastic films can be applied for example by ultrasonic welding. In this context, "yielding" refers to a property which permits a significant yielding of the sealing film under the external pressure without it tearing or leaking, but preferably the sealing film is dimensioned such that it has "fabric reserve" in the region of the window. For example, a drape or a bulge, which allows the sealing film to stow under the influence of pressure from the outside into the interior of the inner sleeve or bulge.

According to a further embodiment, the yielding zone can be arranged on the end face on the inner sleeve. For this purpose, the end face can be glued or sealed, for example, with a film, wherein the end-side sealing film is formed analogous to the film used for the sealing of the window. Again, it is preferably an ultrasonically welded metallized plastic film. This end-face sealing film can be connected to the end face of the sleeve wall in any suitable manner, for example by gluing or by induction welding.

The front-side closure of the sleeve may be a conventional closure, which is pressed out of the inner sleeve by the plunger. In this case, the inner sleeve for pressure equalization on a sealed with sealing film window. Alternatively or additionally, the inner sleeve may also have such a sealing foil on the front side as a closure. According to a particular variant, the end-side sealing film is connected via a locking ring with the sleeve wall, for example by ultrasonic welding. For example, the sealing film may have previously been bonded to this closure ring by gluing, welding or otherwise.

A further preferred embodiment has, in addition to the closure ring, a retaining ring, which in turn is connected to the sealing film. This retaining ring is in turn connected via a membrane or an annular web to the closure in such a way that this membrane or web completely ruptures under the action of a force exerted on the retaining ring. This force can be exerted for example via a crown, which is attached by means of a recording on the plunger of the trigger mechanism and acts with its edge on the retaining ring. When the pressure box is triggered a force on the retaining ring is triggered, which leads to tearing of the membrane and further for ejecting the crown and the retaining ring with the attached sealing foil in the interior of the pressure box. The relatively tight connection of the sealing film in the retaining ring prevents the film over the opening of the open inner sleeve lays or in front of the valve. Likewise, the ejected rigid crown can not interfere with the exit of the sleeve contents into the siphon and the pressurized can contents into the valve.

The construction of the closure of locking ring, annular web, retaining ring and inner sealing foil, which has the necessary elasticity or fabric reserve for pressure equalization, has manufacturing advantages in that a prefabrication of the closure and the subsequent welding of the finished closure with the inner sleeve is possible.

According to another variant, the crown is designed as a cutting crown, which is suitable for cutting the sealing film on the end face of the inner sleeve. For this purpose, it is expedient that the sealing film is stretched over the end region of the inner sleeve or within the closure ring; Too much elasticity is more of a hindrance to cutting the film with the teeth of the cutting bit.

Essential for the cutting crown and its mode of operation is that the end-side sealing foil arranged on the inner sleeve is cut open in a circular manner and completely separated. To this end, the cutting bit preferably has a toothed ring which, after the inner sleeve has been triggered, first perforates the foil and then, starting from the perforations, cuts open, separates and holds it within the toothed rim. The cutting crown is designed so that it is pushed out after the release of the inner sleeve with the captured seal foil cutout from the inner sleeve and enters the outer space of the pressure cell.

Conveniently, the cutting crown is provided with the ring gear on the bottom side with a receptacle into which engages the closure end of the plunger. In this way, the composite of the two parts is secured, as long as they are in the closed inner sleeve. The ram arranged in the inner sleeve is substantially rod-shaped, so that it offers as little resistance as possible to the inner sleeve contents during outflow. It may have lateral guide elements which produce a defined distance from the inner sleeve wall, for example in the form of rods or spokes or spokes connected to the ram rings. It is essential that the ram construction does not hinder the exit of the sleeve contents into the outside space.

Conveniently, the plunger is subdivided into a rod-shaped plunger element, which is located in the interior of the inner sleeve, and a bottom-side trigger member which extends through the sleeve bottom and bottom of the can through to the outside and there establishes the connection to the trigger element. To connect the rod-shaped plunger element with the bottom-side trigger part, either the plunger element at its bottom end or the trigger part on the closure side have a receptacle in which engages the end of the other part.

In order to secure the plunger inside the inner sleeve, a limiting element is necessary, which is arranged for example as an extension in the trigger part of the plunger and cooperates with a in the leadership of the inner container inside circumferential projection. In the resting state of the pressure cell, the plunger is then with its limiting element on the projection. After triggering the can, the plunger moves towards the inner sleeve closure, but returns to its original position under the pressure prevailing in the pressure cell.

The sealing of the inner sleeve in the region of the base element is expediently brought about by the fact that the limiting element has an elastic seal. It can also be designed as a seal overall. Preferably, the limiting element on its periphery circumferentially on sealing lips, which act against the inner surface of the guide. It is understood that the guide in the region in which the extension is effective with the sealing element, has a larger cross section than in the region which passes through the bottom of the can and represents the actual guide. The guide is thus extended on the closure side to the diameter of the limiting element.

The inner sleeve has on the bottom side on the bottom element next to the guide on a holding part. Guide and holding part protrude through the bottom of the can through to the outside, wherein the guide has the function of receiving and guiding the plunger and in particular its trigger part and the holding part assumes the holding function for the inner sleeve. The holding part surrounds the guide concentric at least over part of its length. In general, the holding part protrudes on the bottom side beyond the guide.

As already noted, the cylindrical sleeve wall can have one or more areas that are less rigid and yield elastically under pressure. This is for internal pressure equalization in the system; the inner sleeves are filled and closed under normal conditions. Since an air-free filling and closing is not possible, with a rigid inner sleeve pressure equalization can only be done via penetrating from the outer space in the inner sleeve material. This tendency for subsequent filling can be compensated by the elastic configuration of one or more regions of the inner sleeve. Care must be taken to ensure that the pressure-giving areas do not conflict with the guides of the plunger.

As an alternative to the elastic regions, it is also possible to provide one or more windows which are closed with a yielding sealing film.

According to the invention, for example, metallized films or induction films are used as the sealing film. Induction films can be welded by induction on the object to be sealed and are usually composed of several layers of plastic and metal foils. Induction films are particularly widespread in the food industry, but are also used for sealing containers with water-pulling or flammable liquids. Also suitable are metallic films which can be welded by ultrasound. The inner sleeve is preferably made of plastic. Particularly suitable are polypropylene, but also polyamide grades which better withstand the aromatic solvents frequently used in two-component paints.

The inner sleeve is fixed to the bottom of the pressure cell. The plunger or the triggering part of the plunger protrude through the bottom element of the plunger and out of the bottom of the can. Appropriately, the bottom end of the plunger engages frictionally in the recording of a triggering element, which is triggered by hand. The triggering element is, for example, a trigger button, which causes the release of the inner sleeve and the release of the inner sleeve contents when actuated.

The holding part of the bottom element can on the bottom side - outside the pressure cell - have a thread on which a thumbscrew can be screwed as a triggering element. Also in this case, the trigger element is provided with the receptacle into which the bottom end of the plunger or trigger part protrudes. By screwing the thumbscrew, the plunger is taken and pressed into the inner sleeve, so that the cutting crown cuts open the sealing film.

In pressure cans made of tinplate, the inner sleeve is usually fixed to a base plate, which in turn is crimped into the bottom of the can. For this case, it is expedient to provide a peripheral circumferential projection on the holding part, behind which engages the outwardly directed inner edge of the bottom plate. The inner sleeve is thereby clamped in the bottom plate, wherein an outer circumferential region of the bottom element and the projection serve as an abutment. Appropriately, sealing lips are provided in this content salaried area, which act against the inside of the bottom plate. But it is also readily possible to inject the holding part to the bottom plate.

In particular, when the pressure cell is made of aluminum and has a solid bottom, the inner sleeve is clamped in a recess of the pressure box bottom. For this purpose, the inner sleeve with its holding part through guided this recess and secured with a retaining element, such as a clamping ring, on the underside of the box on the holding part. For this purpose, the holding part can have, for example, a circumferential groove for fixing the clamping ring. The tightness is preferably ensured by a sealing washer between bottom of the can and bottom element of the inner sleeve.

In particular, in drawn aluminum cans, it is expedient to provide in the area of the bottom of the can a fixing that serves to fix a pedestal, but also to guide the trigger element. Such a fixing element is for example approximately bell-shaped or hemispherical and is anchored, for example via the above-mentioned clamping ring or the like in the region of the recess.

In all embodiments, the pressure cell according to the invention may have a base, which serves in particular to surround the triggering element and enclose that an unwanted triggering is difficult and to increase the stability. In the case of pressure box with crimped can bottom of the base can be plugged onto the Krimpwülste or seams, in the case of a trailed soil in aluminum cans, the base is usually attached to the above-mentioned fixing.

The invention is further illustrated by the accompanying drawings of preferred embodiments. From these shows:

Figure 1 shows the closure end of an inner sleeve of a pressure cell according to the invention with a first embodiment of the closure;

Figure 1 a, 1 b, the inner sleeve of Figure 1 in druckbelasted state and after the release;

Figure 2 shows the bottom portion of a pressure cell according to the invention with inserted inner sleeve and push button release; Figure 3 shows another embodiment of the pressure box according to the invention with a turntable release; and

Figure 4 shows another embodiment of a pressure box according to the invention with a drawn bottom and push button release;

FIG. 5 shows a variant of the inner sleeve closure according to FIG.

Figure 6 is a detail of the illustration of Figure 5;

10 as well

Figure 7 shows an embodiment of the pressure cell according to the invention with an inner sleeve according to Figure 5 after the release.

FIG. 1 shows the closure-side end of an embodiment of an inner sleeve, as used in accordance with the invention. The inner sleeve 5 has a cylindrical outer wall 6, which is closed at the end with a closure 7. The closure 7 is connected via a closure ring 7a with the end face 6a of the wall 6 of the inner sleeve. The connection is a welded connection, suitably manufactured by ultrasonic welding.

The closure 7 further consists of a retaining ring 7b, which is connected via a membrane or an annular web 7c with the locking ring 7a. The diaphragm 7c is designed to rupture from the inside of the inner sleeve upon application of force to the retaining ring 7b; this is in the

25 general - for polypropylene as a material - a thickness of 0.20 mm is sufficient.

About the retaining ring 7b, the actual sealing film 17 is placed, which is shown here wrinkled, so under pressure from above / outside in the interior of the inner sleeve 5 can give into it. The sealing film is, for example, a metallized plastic film, such as polypropylene, for example made in one piece with the rings 7a and 7b and then metallized.

Inside the inner sleeve, a plunger 9 is arranged, which ends in a receptacle 9 a. In this recording 9a projects a projection 14 of the crown 13, which can be moved over the plunger 9 in the direction of the closure 7. The edge of the crown 13 acts against the underside of the retaining ring 7b of the cover 7 such that upon actuation of the plunger 9, the crown 13 is pressed against the retaining ring 7b, which leads to the rupture of the membrane 7c between the rings 7a and 7b and to the expulsion of the separated part of the lid 7 with the sealing film 17 and the crown 13 in the pressure can interior.

Figure 1 shows the inner sleeve 5 in a pressureless state with corrugated sealing film. FIG. 1a shows the inner sleeve with sealing foil 17 stretched under pressure, FIG. 1b the opened inner sleeve with ejected crown 13 and detached membrane 17 together with retaining ring 7b.

Figure 2 shows a sectional view of the lower part of a pressure cell 1 according to the invention with inserted inner sleeve 5. The pressure cell itself is shown with the lower part of its frame 2 and the vaulted bottom 3. The vaulted bottom 3 is crimped to the lower end of the frame 2. In the center of the bottom 3 is the bottom plate 4, which is crimped in a conventional manner with the bottom 3. The bottom plate 4 has a complex curved shape with an outward - d. H. to the outside of the pressure cell-facing inner edge 4a, a flat central portion 4b and also outwardly facing outer edge on which merges into the Krimpnaht with the bottom 3.

In the central recess of the bottom plate 4 is fitted the inner sleeve 5, which consists essentially of a frame 6, serving as a closure, here stretched sealing film 17 and a bottom element 8. The bottom element 8 has a guide 10 in the center and a holding part 11 in the outward-pointing (bottom-side) region.

The bottom element 8 itself has, on the bottom side, an outer circumferential circular recess 8a which extends on the flat central section 4b of the Floor plate 4 is supported. Below the recess 8a, the holding part 11 connects, which has a circumferential projection 11b which extends substantially parallel to the recess 8a. The outwardly facing inner edge 4 a of the bottom plate 4 engages behind the projection 11 b of the holding part 11 and fixed in this way the inner sleeve 5 in its position in the center of the bottom plate. 4

In the region of the holding part 11 between the projection 11b and the recess 8a of the bottom element 8 are circumferential sealing lips 11c, which act against the outwardly directed portion 4a of the bottom plate and seal the pressure cell to the outside.

Inside the inner sleeve 5 is the plunger 9, via which the sealing film 17 can be opened on the end face 6a of the sleeve frame 6. The plunger 9 itself consists of a plunger element 9c and a trigger part 9d. The trigger part 9d is located in the guide 10 of the bottom element 8 and is mounted with its closure-side end in a bottom-side receptacle 9e of the plunger element 9c. At the bottom and at the closure end of the plunger element 9c are guide rods 9b, which ensure the central position of the plunger 9 in the inner sleeve.

With its closure-side end 9a, the plunger 9 engages in a receptacle 14 of the cutting bit 13. The cutting crown 13 itself has approximately the shape of a

Spoked wheel and is provided on the rim with a sprocket. The sprocket is suitable to puncture the sealing film 17 after triggering the plunger and cut in a circle. The cut-out foil circle is then held within the seal crown and repelled into the outer space of the pressure cell. A sealing film floating freely in the outer space could cause the valve access to be blocked.

The sealing film 17 is glued or welded on the end face 6a of the sleeve frame 6. It consists of an induction film, ie a metallized plastic film, which can be welded to an opening via an induction process in a manner known per se. Such induction films are particularly suitable because of their metallization, hermetically sealed cavities, ie gas and solvent tight.

The inner sleeve 5 as shown in Figure 2 has a window 16 that is closed with a sealing film 17. The sealing film 17 is elastically adjusted, d. h., It can yield under the pressure prevailing in the outer space of the pressure cell and cause a pressure equalization. Since it is practically not possible to fill and close the inner sleeve without air or gas inclusions, such a compensation mechanism is useful and necessary, in particular to prevent pressure equalization via a diffusing material from the outside space. This is especially true for aerosol cans containing solvents with high creep or penetration for plastics.

The trigger part 9d of the plunger 9 is mounted in the guide 10 of the bottom element 8. It has approximately in the middle of a limiting element 9g that rests on an internally circumferential projection 15 of the guide 10 and prevents the trigger member is pushed out of the sleeve under the pressure prevailing in the pressure cell. In order to ensure the tightness to the outside, the limiting element 9g has a collar with sealing lips 12, which acts against the inner wall of the guide 10 in its closure-side region. It is understood that the guide 10 in this area 10a has an expanded cross section corresponding to the cross section of the limiting element 9e.

In the bottom part of the guide 10, d. H. bottom side to the projection 15, the guide 10 has a smaller cross section, which corresponds to the cross section of the bottom end 9f of the trigger part 9d. Here, the trigger part 9d emerges from the inner sleeve 5 and pressure cell 1 and protrudes into the cavity formed by the bottom of the can 3 in order to frictionally engage with its bottom end 9f in the receptacle 21 of the trigger element 20.

The holding part 11 of the bottom element 8 projects from the recess 8a through the bottom plate 4 in the space formed by the bottom of the can 3. In order to prevent the ram from being driven too far into the pressure cell when the can is triggered, resulting in leaks, it is advisable to limit the travel distance. This travel limit can be done on the one hand via the lower end of the holding part 11 and the bottom of the release button 20, on the other hand on the upper (shutter side) end of the receptacle 21 and the bottom end of the guide 10, as in the case shown.

To protect the trigger mechanism of the bottom of the can is equipped with a base 24 which engages around the Crimean rim between the frame 2 and the bottom of the can 3 and is fixed thereto form fit. The base 24 has a central recess in which the release button protrudes. The foot 24 protects the one hand, the trigger button 20 against unwanted operation and increases the other the stability of the pressure cell.

The holding part 11 is provided in the region of its bottom end with a thread 11a, which is irrelevant in the embodiment shown, but allows a variant of the trigger mechanism, in which the trigger member 9d is driven by means of a wing screw in the inner sleeve. This embodiment is shown in FIG. The inner sleeve can be used for both variants.

The embodiment according to FIG. 3 differs from that according to FIG. 2 only in the triggering mechanism in the bottom area of the pressure box, which contains a turntable. Incidentally, the construction and function of the inner sleeve are illustrated as in FIG. 2 and described therefor.

According to Figure 3, the trigger member 9d projects with its bottom end 9f in the receptacle 21 of the turntable 20, which is equipped in this case with a sleeve 26 with internal thread, which cooperates with the external thread 11a of the holding part 10. In unausgelöstem state, the sleeve 26 is in a lower position relative to the holding part 10. By operation of the wing 25, the sleeve 26 can be further screwed up on the holding part 10 and takes over the recording 21, the trigger part 9d. The plunger 9 acts on the cutting crown 13, which cuts the film 17 circular and is ejected with the film in the outer space of the pressure cell 1. The advantage of this embodiment is that the plunger is fixed in the retracted position and in this way a "falling back" of the cutting crown with the cut-out part of the sealing film 17 is reliably prevented in the upper opening of the inner sleeve 5.

Incidentally, the pressure box also here has a base 24 which surrounds the trigger mechanism and protects against external impact. The base 24 is naturally tuned to the dimension of the trigger element 20. It is understood that instead of a single-wing screw 20, a two-leaf screw can be used.

Figure 4 shows a variant of the invention, which is adapted to a pressurized can with pulled bottom 3. The pressure cell 1 with its frame 2 merges seamlessly into the bottom 3, which has a central recess 3a into which the holding part 11 of the inner sleeve 5 is inserted. A disk seal 22, which adjoins the recess 8a of the bottom member 8 and rests on the inside of the bottom 3 immediately adjacent to the recess 3a, serves to seal the pressure cell to the outside. A clamping ring 18 fixes the sleeve 5 below the bottom 3 in the region of the recess 3a.

In the variant shown, the pressure cell in the bottom region on a bell-shaped fixing element 23 which is held with the clamping ring 18 in its position immediately adjacent to the bottom element 3 concentric with the recess 3a. The fixing element 23 serves to fix the base 24, which can not be attached directly to the box for lack of crimping. At the same time, the fixing element serves as an outer guide for the release button 20, which acts in the same way on the plunger 9, as shown in Figure 2. It is understood that this variant can be provided with a turntable release.

FIG. 5 shows a further variant of the closure-side end of an inner sleeve, as used in accordance with the invention. The inner sleeve has a cylindrical outer wall 6, which has the closure 7 on the front side. The closure 7 is connected to the end face 6a of the wall via a closure ring 7a. 6 connected to the inner sleeve. The connection is a welded connection, suitably produced by ultrasonic welding.

The closure 7 consists of a retaining ring 7b, which is connected via a membrane or annular web 7c with the locking ring 7a. The diaphragm 7c is designed so that the force acting on the retaining ring 7b tears it out of the interior of the inner sleeve.

The crown 13 has on the bottom side an extension 14, which, as shown in Figure 1, ends in a receptacle of the plunger 9.

Figure 6 shows a detail of the representation of Figure 5 to illustrate the interaction of closure 7 and crown 13. The closure ring 7a and the retaining ring 7b are connected to each other via the membrane 7c, which has a dividing line T as a weakening zone in the illustrated case. T is the dividing line along which the retaining ring tears off the locking ring when the crown 13 moves in the direction of the sealing foil 17. A circumferential projection V on the crown 13 serves to assist the tearing and severing process by acting against the lower edge 7d of the retaining ring 7b when the deployment is initiated by the upward movement of the crown 13. *** "

In the region of the end face 6a of the inner sleeve wall 6 is the weld S, along which the closure ring 7a is welded to the wall 6.

FIG. 7 shows a pressure cell according to the invention with the bottom area and the inserted inner sleeve after the release. Crown 13 and sealing film 17 with retaining ring 7b are already outside of the inner sleeve 5, the closure ring 7a remains on the front side of the sleeve wall 6. The crown 13 has a pointing to the bottom side extension 14 with lateral guide rods 14b, which via a recording with the plunger 9 cooperates.

Claims

claims

1. Pressure cell (1) for two-component aerosol systems, in particular for 2K mounting foam systems, with a frame (2), one in a dome

5 arranged valve, a bottom (3) and an on the bottom (3) arranged inner sleeve (5), wherein the inner sleeve (5) with a cylindrical sleeve wall (6), a closure (7), a bottom element (8) and a in the inner sleeve (5) is displaceably arranged and provided with its end (9f) by the bottom element (8) protruding plunger (9) and the Bodenele- ment (8) a guide (10) for the plunger (9) and a holding part (11) which is guided through and fixed to the bottom (3) of the pressure cell (1), wherein the plunger (9) cooperates with a release element (20) arranged outside the pressure cell, characterized in that the inner sleeve (5) has at least one yielding zone for pressure equalization between the can interior and sleeve interior.

2. Pressure cell according to claim 1, characterized in that the sleeve wall (6) has a yielding zone.

3. Pressure cell according to claim 1 or 2, characterized in that the yielding zone is formed by a sealing film (17) over a window (16) in the sleeve wall (6).

4. Pressure cell according to claim 1, characterized in that the yielding zone is formed by a on the end face (6 a) of the sleeve wall (6) applied sealing film.

5. Pressure cell according to claim 3 or 4, characterized in that the sealing film (17) is a metallized plastic film or a plastic / metal composite film.

6. Pressure cell according to claim 5, characterized in that the sealing foil (17) is an induction foil.

7. Pressure cell according to one of claims 4 to 6, characterized in that the plunger (9) with a crown (13) is releasably connected, the bottom side has a receptacle (14) for the closure-side plunger end (9a).

o 8. A pressure box according to claim 7, characterized in that the

Closure (7) has a closure ring (7a) which is welded onto the end face (6a) of the sleeve wall (6) and in which the compliant sealing film is arranged.

9. Pressure cell according to claim 8, characterized in that the closure (7) within the closure ring (7a) has a retaining ring (7b) which is connected to the locking ring via an annular web connection (7c), wherein the crown (13) when triggered on the retaining ring (7b) acts to separate it from the locking ring.

10. Pressure cell according to claim 8 or 9, characterized in that the sleeve wall (6) is ultrasonically welded to the end face (6a) with the closure ring (7a).

11. Pressure cell according to claim 7, characterized in that the crown (13) on the closure side has a sprocket.

12. Pressure cell according to one of the preceding claims, characterized 5 characterized in that the plunger (9) is rod-shaped and lateral

Has guides (9b).

13. Pressure cell according to one of the preceding claims, characterized in that the plunger (9) is divided into a rod-shaped plunger element (9c) and a bottom-side trigger part (9d).

14. A pressure cell according to claim 13, characterized in that the bottom-side release part engages (9d) in a bottom-side receptacle (9e) of the rod-shaped plunger element (9c).

15. A pressure cell according to any one of the preceding claims, characterized in that the plunger (9) has a limiting element (9g) which cooperates with a in the guide (10) on the inside circumferential step (15) lo.

16, pressure cell according to claim 15, characterized in that the guide (10) on the closure side to the diameter of the limiting element (9e) expands.

17. A pressure box according to claim 16, characterized in that the i5 delimiting element (9 e) has an elastic seal (12), which against the

Inner wall of the extended part of the guide (10) acts.

18. Pressure cell according to claim 17, characterized in that the elastic seal (12) is a lip seal.

19. Siphon according to one of the preceding claims, characterized in that the holding part (11) at least partially concentrically surrounds the guide (10).

20. Siphon according to one of the preceding claims, characterized in that the inner sleeve (5) consists of plastic.

21. The pressure cell according to one of the preceding claims, characterized in that the bottom end (9f) of the plunger (9) is frictionally mounted in the receptacle (21) of a triggering element (20).

22. A pressure cell according to claim 15, characterized in that the triggering element (20) is a release button.

23, pressure cell according to one of claims 1 to 21, characterized in that the holding part (11) on the outside a thread (11 a).

5 24. A pressure box according to claim 23, characterized in that the

Trigger element (20) is a thumbscrew.

25. Pressure cell according to one of the preceding claims, characterized in that the holding part (11) peripherally a concentrically encircling projection (11 b) behind which an outwardly facing inner edge lo of a bottom plate (4) engages, which with its outer edge with the Canned bottom (3) is crimped.

26, pressure cell according to claim 25, characterized by the closure side to the projection (11 b) arranged and concentric circumferential sealing lips (11 c) which cooperate with the outwardly facing inner edge of the bottom plate (4) i5 of the can bottom (3).

27. Pressure cell according to one of claims 1 to 24, characterized in that the inner sleeve (5) with the holding element (11) in a recess (3a) of the can bottom (3) is clamped.

28. Pressure cell according to claim 27, characterized by a sealing washer 20 (22) between bottom of the can (3) and bottom element (8) of the inner sleeve (5) and a clamping ring (18) on the holding part (11).

29. Pressure cell according to one of claims 27 and 28, characterized in that the can bottom (3) additionally has a fixing element (23).

30. Pressure cell according to one of the preceding claims, characterized by a bottom of the can (3) fixed, the trigger element (20) concentrically surrounding base (24).