WO2024068799A2

WO2024068799A2 - Cartridge piston device for inserting into a cartridge, method for venting and closing a cartridge, and use of a cartridge piston device

Info

Publication number: WO2024068799A2
Application number: PCT/EP2023/076812
Authority: WO
Inventors: Mike KONDZIELA; Stephan Dekert; Andreas Grundler
Original assignee: Kulzer Gmbh
Priority date: 2022-09-29
Filing date: 2023-09-27
Publication date: 2024-04-04
Also published as: WO2024068799A3; DE102022125144A1

Abstract

A cartridge piston device (1) for inserting into a cartridge (4) and for venting and rear-side closing of the cartridge (4) is illustrated and described, having a closure element (3) for inserting into the piston (2), and the closure element (3) or at least part of the closure element (3) inserted into the recess (11) is arranged so as to be guided adjustably in the insertion direction (18) from an open position fluidically opening up the channel structure (10) into a closed position fluidically closing the channel structure. In order to configure the cartridge piston device to be more user-friendly and to make it less prone to error and to improve the venting, it is provided that, in the open position, the closure element (3) for providing the open position: is held fixed, in particular with a force fit, in the recess (11) and/or strikes against the latter at least in the extraction direction (19).

Description

KDP12357WO 27 September 2023

Cartridge piston device for insertion into a cartridge, method for venting and closing a cartridge and use of a cartridge piston device

The present invention relates to a cartridge piston device with a piston for insertion into a cartridge and for venting and closing the rear of the cartridge.

When closing a cartridge filled with a pasty product or cartridge contents - in particular an impression material for the dental sector - by inserting a cartridge piston device or a piston into the cartridge that is open at the back, air pockets usually form between the piston and the cartridge contents. For this purpose, it is known to provide the piston with a channel structure for venting. When the piston is inserted and pushed further into the cartridge, air can escape from the cartridge through the channel structure. To prevent the cartridge contents themselves from escaping from the cartridge through the channel structure, it is known from DE 200 10417 U1 to always close the channel structure and only release it when the piston is pushed in, for example. It is also known from DE 200 10 417 U1 to dimension the channel structure sufficiently small so that the pasty cartridge contents cannot pass through the channel structure. Furthermore, the channel structure can alternatively be closed by a rotary closing movement of a separate part, such as a closure element, after the insertion of the piston by an additional work step.

The disadvantage of the known cartridge piston device is that venting the cartridge is not very user-friendly because additional tools are required. It can also happen that air pockets remain in the cartridge if the channel structure is closed again too soon or if venting is completely forgotten or carried out poorly by releasing the channel structure.

It is therefore the object of the present invention to make the known cartridge piston device more user-friendly and to reduce the susceptibility to errors and improve ventilation. In particular, the process of closing the cartridge, including inserting the cartridge piston device, should be able to be carried out faster and more reliably.

The task is solved by the features of claim 1, in a method with a cartridge piston device by the features of claim 12, a kit according to claim 12 and through the use according to claim 13. Preferred embodiments are each the subject of the subclaims and are disclosed in detail in the description.

According to the invention, a cartridge piston device is provided for insertion into a cartridge and for venting and closing the rear of the cartridge, with a, in particular at least substantially cylindrical, piston and with a closure element for insertion into the piston. The piston has: a front side, a rear side facing away from the front side, in particular opposite the front side, an outer side with a circumferential sealing groove and/or seal for circumferential sealing on an inner surface of the cartridge, a recess in the region of the front side for inserting the closure element in an insertion direction, a channel structure fluidically connecting the recess and the rear side for venting the cartridge, the insertion direction pointing, at least substantially, from the front side to the rear side and an extraction direction opposite the insertion direction. The closure element inserted or insertable into the recess or at least a part of the closure element inserted into the recess is arranged or can be arranged so as to be adjustably guided in the insertion direction from an open position fluidically releasing the channel structure into a closed position fluidically closing the channel structure, wherein the piston has a support surface for the rear side of the closure element in the direction of the front side, which support surface is formed substantially perpendicular to the central axis of the piston and is opposite the front surface of the closure element.

It is preferred if the piston has a recess on the front side with a support surface for the back of the closure element, which is designed essentially perpendicular to the central axis of the piston. The recess is preferably cylindrical or conical or tapered in the shape of a truncated cone. The recess preferably has a depth of 0.01 to 10 mm, in particular 1 to 10 mm, wherein the surface of the recess is preferably essentially planar and in particular has the pre-channel structure. The back of the closure element is preferably designed as a positive and the recess as a negative with a larger circumference. Furthermore, the recess is preferably larger in circumference than the circumference of the back of the closure element, in particular the circumference of a cover on the back of the front face. According to an alternative, a circumferential groove is formed in the recess with the closure element inserted, which is in particular formed by an auxiliary sealing element, in particular a protruding seal, on the head side, in particular the front face and/or back, of the closure element, a circumferential sealing lip on the head side of the closure element. and/or a circumferential sealing lip or seal on the lid fluidically closes the groove in the closed position of the cartridge piston device.

The head side of the closure element advantageously has a back which is opposite the end face.

It is particularly advantageous that the closure element for providing the open position is held fixed in the recess in the open position, in particular in a force-fitting manner, and/or that the closure element for providing the open position strikes the recess in the open position at least in the pull-out direction.

A support surface is considered to be substantially vertical if it is formed at an angle to the central axis of the piston of 80° to 100°, in particular of 85° to 95°, particularly preferably plus/minus 2°. Preferably, the support surface is flat or planar. Preferably, the support surface has a pre-channel structure. The pre-channel structure can advantageously extend radially from the recess at least partially in the direction of the outer circumference of the piston. Optionally, the piston can have additional openings which extend from the front to the rear of the piston and can be closed by the closure element. The rear of the closure element is preferably also flat or planar. The support surface can have a diameter of at least 11 mm, in particular 11 to 23 mm, preferably 17 mm, optionally +/- 2 mm, in particular +/- 1 mm. The rear side of the head side, in particular also the head side, of the closure element preferably has a diameter that is less than or equal to 2 mm, in particular less than or equal to 1 mm to 0.0001 mm, preferably less than or equal to 0.5 mm to 0 mm smaller than the support surface in order to enable the formation of a circumferential groove or at least a recess for fluid exchange.

According to a preferred embodiment of the piston, a pre-channel structure runs in the support surface up to the recess. Furthermore, it is preferred if optional alternative or additional openings are provided in the support surface, which are fluidically connected to the rear side of the piston or in the direction of the rear side of the piston.

The openings are advantageously arranged in the support surface and below the rear side which is opposite the end face of the closure element; in particular, the support surface and the rear side are essentially planar and advantageously essentially perpendicular to the central axis of the closure element and/or to the central axis of the piston. The recess and the channel structure can be components of a central vent hole in the piston. A pre-channel structure preferably runs radially from the recess in the direction of the outer circumference of the piston. The channel structure particularly preferably runs in the recess and the pre-channel structure runs radially from the recess at least partially outwards in the direction of the outer circumference of the piston, the pre-channel structure being arranged in the support surface of the piston. In the closed position, the support surface of the piston comes into contact with the rear side of the closure element, preferably the rear side of the closure element rests on the support surface, preferably in a fluid-tight manner. Both the support surface and/or the pre-channel structure are essentially planar. Furthermore, the support surface advantageously runs essentially perpendicular to the central axis of the piston. When the piston is inserted into the cartridge, the central axis of the piston is essentially parallel to the central axis of the cartridge. The closure element, which is preferably designed as a plug, is essentially rotationally symmetrical and/or has a central axis, can be inserted into this vent hole. The closure element is preferably axially movable in the vent hole, or more precisely in the recess, at least from an open position that does not fluidically close or release the channel structure to a closed position that closes the channel structure. In the installed state, that is to say at least when the cartridge has not yet been vented and when the closure element is in the open position, the closure element or the plug protrudes from the piston and keeps the vent hole in the piston free; this enables a fluid connection from the front to the back of the piston through the piston via the channel structure. When the piston is pushed forward or the piston is adjusted in the cartridge, the air from the cartridge can escape through the channel structure or the vent hole through the piston and out of the cartridge. As soon as the impression material filled into the cartridge comes into contact with the piston, in particular with the front and/or with the closure element, and in particular as soon as a sufficiently large axial force from the rather viscous or pasty impression material acts on the closure element, the closure element is pressed further into the piston. This closes the channel structure or the vent hole or prevents fluid passage through the piston, and only when the cartridge is at least almost completely vented. This can make a manual closing movement of the closure element on the piston unnecessary.

A piston for a cartridge is typically inserted into the back of the cartridge, in particular into a piston opening, and closes it, at least approximately. preferably airtight or fluidically tight. The piston usually has a front side facing in the direction of the cartridge contents, in particular approximately flat, a rear side facing away from it, an outside with a circumferential sealing groove and/or seal for circumferential sealing on an inner surface of the cartridge. It is also possible for the piston to face the back of the cartridge contents. Preferably, the cartridge piston device has a planar surface at least in the area of the end face of the head side of the closure element in order to enable automatic closure by force from the media. The front is on the media side, ie aligned towards the contents of the cartridge. The rear side is arranged on the apparatus side or the conveyor side.

The sealing groove and/or seal is designed in such a way that the piston can be moved axially in the cartridge and yet forms a fluid seal in the area of contact with the inner surface. In particular, when the cartridge is full or has no other (open) opening apart from the piston opening, the remaining volume between the piston and the space in the cartridge is reduced when the piston is pushed in, which can cause the pressure in the cartridge to rise. In other words, air would then be trapped and/or compressed in the cartridge, which would typically require venting. In any case, the cartridge contents should not usually be in permanent contact with the air. For this purpose, a channel structure can be provided in the piston, which basically connects the front and the back fluidically. Fluids are understood to be gases and liquids, so that gases and liquids can pass through a fluid connection or a fluid gap opening into the recess. Due to the channel structure, venting of the cartridge closed by the piston can take place as long as the channel structure is not closed, at least temporarily.

The recess is to be understood as meaning a (through) bore, a material withdrawal, a hole, a guide, a receptacle and/or a (fluidic) passage, in particular a (fluidic) passage from the front or rear side to the channel structure. The recess serves to accommodate or insert the closure element. The recess is preferably arranged centrally on the front of the piston. In particular, in the case of an approximately cylindrical or cylindrical piston, the recess can be arranged on the central axis of the piston, ie at least approximately centrally between the side surface of the piston. The central axis of the piston is to be understood as meaning an axis which extends at least through the front and rear sides and is arranged at least approximately the same distance from the side surface all the way around. The channel structure is to be understood as meaning a bore, a material withdrawal, a hole, a groove, a slot, and/or a (fluidic) passage, in particular a (fluidic) passage from the rear to the front and/or from the rear or front to the recess. The channel structure serves, at least essentially, for air transport or for fluidic connection. The recess and the channel structure can have the same or similar features and/or merge smoothly into one another.

The possibility that several, for example two, three, four or more, recesses can be provided on the front should not go unmentioned. Alternatively or additionally, a recess can also be provided on the rear side or two, three, four or more recesses can be provided on the rear side. Independently or dependently of this, several channel structures can also be provided. Several channel structures can, at least essentially, run parallel and/or be connected to one another between the front and the rear. A recess which - contrary to the rule - is provided on the rear side can be connected to the same channel structure to which a particularly opposite recess on the front side is also connected. Overall, one or more of the aforementioned features can bring about an improvement in the ventilation, the operability and the reliability of the cartridge piston device.

In order to close the channel structure, the closure element can be inserted into one or the recess, which is designed to be adjustable from the open position to the closed position, if necessary also back. In the open position, the channel structure is fluidically released, that is to say a fluidic passage through the channel structure is possible, at least approximately unhindered. In the closed position, the channel structure is fluidically closed, which means that a fluidic passage through the channel structure is only possible with hindrance or is not possible at all. In particular, highly viscous fluids or pasty cartridge contents can no longer pass through the channel structure if there is a suitable reduction in cross-section in the area of the channel structure, so that the term closed position can also include a certain reduction in cross-section because a highly viscous content of the cartridge that is stationary in or on the channel structure ultimately becomes one Can effectively prevent passage of the remaining cartridge contents and / or air through the channel structure.

Usually the front is facing the cartridge or the cartridge contents. Then the closure element inserted into the recess is also facing the cartridge contents and can come into contact with it. Alternatively, it is also possible for the rear side to face the cartridge or the cartridge contents; then the recess on the front of the piston is accessible from the outside or the back of the cartridge when the piston is pushed into the cartridge, so that the closure element can be brought into the closed position from the outside and/or manually.

In the open position, the closure element is, for example, non-positively fixed or clamped against displacement in and/or against the insertion direction, so that the closure element is secured against falling out of the recess and/or against further insertion or adjustment. However, if a sufficiently high force is applied to the closure element in the axial direction or in the insertion direction, the closure element can be pushed in further axially (and/or pulled out again). It is advantageous and preferred that the closure element is fixed and/or abuts in the open position, in particular abuts in the pull-out direction, but that a fluidic passage past the closure element is not hindered.

In the closed position, the locking element is, for example, positively and/or non-positively secured or clamped against displacement/adjustment in the insertion direction and/or in the extraction direction.

Preferably, a clamping force acts between the piston and the closure element, in particular at least in the closed position. The clamping force can hold the closure element in its position, in particular because the clamping force can be aligned transversely to the central axis and/or to the insertion direction or pull-out direction.

Alternatively or additionally, a latching connection and/or a snap connection is preferably provided between the closure element and the piston or the recess. The closed position - but also the open position - can be positively blocked or secured in such a way that pulling it out in the extension direction is only possible with great effort or not at all, for example caused by the latching connection and / or the snap connection, in particular by means of a snap ring.

According to a preferred embodiment of the invention, the closure element has a head side with a front surface. Under the head side, a - preferably along the central axis of the closure element located outside - section of the closure element, while the end face is to be understood as a surface or the outward-facing surface of the head side. In particular, the head side is an at least substantially piston-shaped, cylindrical and/or cylinder-shaped section on the closure element. The head side can preferably be designed as a cover, in particular as a planar cover.

The front surface provides an attack surface for introducing force onto the closure element as a whole, so that it can be adjusted from the open position to the closed position. The introduction of force can be effected both by the cartridge contents and manually. The front surface is preferably arranged, at least essentially, parallel to the front and/or the rear and/or transverse to the insertion direction or extraction direction in order to achieve user-friendly operation.

When the piston is pushed into the cartridge, the trapped air can initially escape through the piston (because the open position is then preferred). It then depends on whether the front (case 1) or the back (case 2) faces the cartridge contents. In the 1st case, when the front meets the cartridge contents, a force in the insertion direction will act on the face; Then in particular the closed position - for example during venting and/or at the end of venting - is caused by the closure element being pushed into the piston by applying force on the end face, while the piston is being pushed into the cartridge in the opposite direction. In the second case, the closure element will not simply be adjusted, but only the piston will come to a standstill when the pressure in the ultimately vented cartridge increases; The closure element must ultimately be adjusted into the closed position manually, ie manually and/or by means of a device which, for example, already inserts the piston. In one embodiment, it can be provided that the closure element is pushed into the piston by applying force on the end face, and optionally, if complete closure into the closed position does not take place, the closure element can be moved into the closed position manually, for example on the foot side. Alternatively, a combination of the first case and the third case can be provided. In this embodiment, the closure element is closed by applying force to the end face of the piston and the end face of the closure element. Optionally, a further closure element can also be provided on the piston, which allows the piston contents to be ventilated again in this position. Preferably it is also provided that, at least in the open position, the end face protrudes from the front. It is then easy to see whether the open position is present or whether the open position is not set correctly, especially if the closed position does not result in such a clear or a different clear projection of the end face.

Alternatively or additionally, it is possible that, at least in the open position, a gap is formed between the front face, in particular the head side, and the piston, in particular a recess of the piston, which fluidically opens into the recess, in particular as part of a pre-channel structure. A reliable venting function is provided via the gap, which just as reliably prevents a fluidic passage when the gap is closed in the closed position, and/or which is also, at least approximately, closed.

Further alternatively or additionally, it is provided that, at least in the closed position, the end face is at least essentially flush with the front or is recessed in the front. Preferably, at least in the closed position, the head side can also be recessed further than in the open position.

Each of these above options aims to ensure that the closed position is clearly visible to the operator in order to avoid further operating errors, e.g. erroneous insertion of the piston with the closure element in the closed position.

According to a further preferred embodiment of the invention, it is provided that the head side and/or the front surface and/or rear side is designed to be at least substantially round and/or corresponding to a, in particular and/or at least substantially, cylindrical recess in the recess. In particular, if the closure element corresponds, at least in sections, to the piston, for example to the recess and/or to the/a recess in the piston, the closure element can be inserted into the piston easily and with little risk of error, for example to reach the open position and the closed position.

In preferred embodiments, in particular with sealing surfaces in the recess, the recess has a fluidic connection from the front of the piston to the rear of the piston, in particular the recess extends from the front of the piston to the rear of the piston. In particular with sealing surfaces provided inside the recess, which can be conical and/or cylindrical, for example, and with corresponding sealing surfaces of the closure element interaction. The corresponding surfaces of the closure element can be designed as a sealing element, cone, taper, truncated cone, truncated cone section, cylindrical or can comprise polygonal surfaces. In an alternative embodiment, the recess can be designed as a blind hole if, for example, the closure element has a rear side opposite the front surface and the rear side acts as a sealing element. In particular, the front surface and rear side of the head side are designed as a cover, preferably as a planar cover. The plane of the cover of the closure element is preferably designed essentially perpendicular to the central axis of the closure element. The cover is preferably essentially planar, in particular on the front surface and/or on the rear side. In a particularly preferred embodiment, the rear side acts as a sealing element in the closed position for sealing openings that fluidically correspond with the rear side of the piston.

It is helpful if the closure element, in particular the head side and/or the end face, and/or the piston, in particular the recess and/or the recess, are designed to be round and/or corresponding to one another and/or insertable into one another. This means that errors in use, such as incorrect insertion of the closure element, can be avoided.

The ratio of the front surface of the closure element to the surface of the front of the piston - without the portion of the front surface of the closure element - is preferably from 1:5 to 1:20, preferably 1:5 to 1:10. It is also particularly preferred if the front surface of the closure element is essentially flat or planar. It is particularly preferred if the front surface of the closure element does not deviate from a planar plane by more than plus/minus 0.1 to 5 mm. It is also preferred if an imaginary plane, in particular a planar plane, in the front surface, in particular a substantially planar front surface, of the closure element is essentially perpendicular to the central axis of the piston. In the present case, essentially perpendicular is understood to mean angles of 81° to 90°, in particular 85° to 90°.

The pressing force of the closure element with an end face, in particular with a planar end face, preferably with an end face of 0.3 to 5 cm or alternatively with a ratio of 1:5 to 1:20 of the end face of the closure element to the front of the piston, is preferably greater than 5 N, particularly preferably from 200 N to 500 N, preferably from 200 N to 300 N. Corresponding preferably means that at least in sections there is a geometric positive of one part/section and a geometric negative of the other part/section. If sections or parts correspond to one another, ie in particular the closure element to the recess and/or the head side to the recess, narrow gaps can be realized if required and support for sealing or closing the channel structure can be made possible.

It is also possible for the recess to have projections, for example on the edge. Alternatively or additionally, the projections of the recess can correspond to, for example, edge-side recesses on the head side. Alternatively or additionally, it is possible for the recess to have recesses and/or for the head side to have projections. The projections or recesses can be part-circular or semi-circular, preferably with the corresponding central axis of the part circle or semi-circle being arranged parallel to the central axis of the piston and/or closure element. The projections and recesses can mesh with one another in the manner of a toothing. In this way, the fluidic closure can be further improved in the closed position. This can also result in ease of use, in particular because less effort may be required to adjust the closure element, and/or because incorrect insertion and/or incorrect adjustment of the closure element is made more difficult. One, two, three, four or more projections or recesses can be provided, in particular arranged distributed all around.

In a further preferred embodiment, the closure element has a sealing element, in particular a cone, for sealing on a sealing surface of the recess. The sealing element is in particular a conical or truncated cone-shaped section of the closure element, preferably convex and/or circumferential. This ensures that the parts fit together securely and precisely. In particular, a cone, a cone shape or a truncated cone shape are well suited for a flat and therefore sealing contact of the parts if at least one part or material involved has sufficient elasticity.

The sealing element alternatively or additionally has a sealing ring (e.g. O-ring or sealing ring) or is formed by a sealing ring. In particular, the sealing ring can only rest on the closure element in the open position and in the closed position - for fluidic closure - rest on both the closure element and the piston. in particular the recess, particularly preferably all around the closure element and the piston.

In particular, the recess has a or the sealing surface. The sealing surface of the recess can be a conical or truncated cone-shaped section of the piston, preferably concave and/or circumferential. The sealing surface can also be, at least approximately and/or partially, cylindrical.

In the closed position, in particular around the central axis of the closure element, the sealing surface and the sealing element can be pressed and/or clamped and/or jammed against one another, in particular in such a way that a fluidic closure or sealing is present, that the channel structure is fluidically closed and/or that an adjustment of the closure element from the closed position in the pull-out direction is difficult or, at least approximately, impossible.

The sealing surface and the sealing element can be spaced apart from one another in the open position, in particular in such a way that there is no fluidic closure or sealing and/or that the channel structure is not fluidically closed and/or that the channel structure is fluidically released.

In a further preferred embodiment, the closure element has an auxiliary sealing element, in particular a sealing lip, for contact with a further sealing surface of the recess, preferably wherein the auxiliary sealing element is on the head side, in particular the end face and/or back, and/or circumferentially around the head side, in particular End face and / or the back - in particular around the central axis of the closure element - is arranged.

The sealing auxiliary element can release a gap between the piston and the closure element in the open position and/or close or seal in the closed position. The sealing auxiliary element can reduce the pressure acting on the sealing element in the closed position when the piston is used in a cartridge, so that overall a higher pressure can be absorbed by the piston with the closure element when the closure element is in the closed position. In this way, reliability can be further improved.

In a further preferred embodiment, it is provided that the closure element has a securing section for securing the closure element relative to the piston, in particular by means of a securing means of the piston, particularly preferably a snap ring of the piston. The securing section and the securing means are preferably designed to correspond to one another, for example in the form of a clamping, play-affected and/or latching connection between the piston and the closure element in the insertion direction or withdrawal direction. It is advantageous that the axial play between the securing section and the securing means can provide the adjustability between the open position and the closed position and/or can ensure that the closure element cannot be pulled further out of the piston in the withdrawal direction in the open position. This prevents the closure element from being lost - in particular when inserting the piston into the cartridge.

In particular, the securing section can be designed to run around the central axis of the closure element and/or as a recess, projection and/or locking lug and/or have the same.

The securing means is in particular a part and/or section of the piston, for example in the area of the recess and/or the channel structure. The securing means can be designed as a snap ring or locking ring, as a locking lug and/or as a projection and/or have these.

A snap ring is present, for example, as a ring-shaped, circumferential projection in a recess of a component or on a circumferential outer surface of a component - whereby this component can be the piston and/or the closure element - and has a mobility radially relative to the central axis of the component. The mobility is preferably achieved by an elastic deformation of the snap ring itself. The snap ring is preferably formed by an annular, i.e. at least essentially circumferential, body that can be expanded and/or compressed.

The circumferential projection can, for example, be briefly expanded and finally snap into the securing section in sections when the closure element is inserted into the recess and reaches the open position, and preferably remain in the securing section in the positions between the open position and the closed position. Then, for example, there is a positive connection between the piston and the closure element, which acts in the insertion direction or pull-out direction. In an alternative, the closure element is particularly preferably designed symmetrically about its central axis. Furthermore, the closure element comprises a head side, in particular a cylindrical head side, with a preferably flat end face, a sealing element, a guide section and optionally a taper. The end face can be arranged transversely, in particular perpendicularly, to the central axis of the closure element. An auxiliary sealing element can be arranged all around the head side, adjacent to the end face, which is advantageously designed in the present case as a seal, sealing lip, sealing lip with openings for a fluidic passage immediately before the closed position. The sealing auxiliary element preferably seals a circumferential groove around the head side of the closure element in the piston. The sealing auxiliary element is designed to seal the recess all around in the closed position. A sealing element can adjoin the back, opposite the end face of the head side. A sealing element designed as a cone or cylinder, optionally with at least one circumferential groove and/or circumferential sealing ring, can adjoin the rear side, opposite the end face.

The end face advantageously has a rear side which is opposite the end face of the closure element. Alternatively, the end face of the closure element has a back side of the closure element, which is opposite the end face of the closure element.

The closure element preferably has a securing section which is designed as a recess running around the central axis or as a projection running around the central axis. A securing means or a snap ring or also a circulating ring can engage in the recess and abut axially. Conversely, the projection running around the central axis can engage in a recess in the recess as a securing means. The guide section can adjoin the securing section. The guide section is advantageously designed to run all the way around the central axis and preferably at least in sections to be cylindrical. A taper can be connected to the guide section. The closure element is advantageously designed to be essentially complementary to the recess and countersink in the cartridge piston device. The recess is designed as a channel from the front to the rear, with the front facing the media side or the inside of the cartridge and optionally filled cartridge contents and the rear being arranged on the device side or the conveyor side. A further preferred embodiment of the invention provides that the closure element and/or the piston, in particular in the region of the recess and/or along the insertion direction or extraction direction, has a venting option, in particular having groove(s) or slot(s). The venting option can enable a fluidic exchange between the front and the rear of the piston, preferably when the closure element is in the open position. The venting option, for example, fluidically connects the recess to the channel structure when the closure element is in the open position; furthermore, preferably no fluidic exchange can take place via the venting option when the closure element is in the closed position, in particular because the venting option can, for example, be partially covered.

The venting option, in particular the groove or slot or also the grooves or slots, can extend on the closure element from the sealing element to an axial location of the closure element further away from the sealing element. If several grooves or slots are provided for the ventilation option, this applies to the individual grooves or slots. The venting option can alternatively or additionally extend from the sealing surface to a point further away from the sealing surface and/or towards the rear of the piston. In any case, the ventilation option does not have to be directly connected to the sealing surface or the sealing element at one of its two ends, but can overlap or be designed at a distance from the sealing surface or the sealing element.

In particular, the closure element, at least in the open position, essentially blocks the cross-section of the recess, whereby the venting option, however, ensures a certain fluidic connection - e.g. for venting - along the closure element. In particular, the venting option ensures a fluidic connection between the recess and the channel structure, in particular in the area in which the cross-section of the recess is essentially blocked by the closure element.

A preferred embodiment of the invention is characterized in that the piston has a pre-channel structure on the front and/or on the rear side. A pre-channel structure is preferably understood to mean a further channel structure which is fluidically connected upstream and/or downstream of the channel structure - in particular indirectly or directly. The pre-channel structure improves the venting function in particular by allowing the air to be discharged to be taken up over a large cross-section and/or in a plurality of areas rather than just in the immediate area of the recess. and can be discharged or tapped via the piston. Without a pre-channel structure, the area where air can be discharged would only be directly in the area of the closure element and would therefore be comparatively small.

In particular, the pre-channel structure extends transversely, i.e. at least substantially perpendicularly, to the insertion direction or extraction direction and/or to the central axis of the piston. Alternatively or additionally, the pre-channel structure at least substantially covers the front and/or the rear side and/or extends over the front and/or the rear side at least substantially flatly and/or in a star shape and/or distributed in particular evenly around the central axis.

The pre-channel structure can fluidically connect the front side and/or sections of the front side to the recess, the channel structure and/or the rear side. Alternatively or additionally, the pre-channel structure can fluidically connect the rear side and/or sections of the rear side to the channel structure and/or the recess.

A further preferred embodiment is characterized in that the pre-channel structure, in particular on the piston, has recesses that are open to the outside and/or towards the cartridge and/or in the form of grooves, preferably wherein the recesses are arranged on or within the front side and/or the rear side, at least approximately, over the entire surface and/or in a distributed manner.

The particularly constant width of the pre-channel structure can be in the range from 0.01 mm to 1 mm, preferably in the range from 0.1 to 0.5 mm, particularly preferably the width is 0.2 mm +/- 10%. This is a sufficiently narrow value so that pasty cartridge contents in particular can only penetrate the pre-channel structure with difficulty or not at all.

The depth of the pre-channel structure or a depression in the pre-channel structure, in particular measured from a plane on the front in the insertion direction and/or along the central axis of the piston, is in particular in the range 0 to 10 mm, preferably 0.1 to 5 mm, in particular 2 up to 4 mm. In particular, the pre-channel structure is less deep further away from the central axis than close to the central axis. The pre-channel structure can open into an edge recess near the outside - in particular continuously - with the same, similar or completely different depth.

In particular, the pre-channel structure faces or is open to the cartridge contents. If the pre-channel structure has more than just the central channel, preferably at the front of the piston, If the area of the recess on the front side is fluidically connected - directly or indirectly - to the rear side, areas of the front side that are closer to the edges can also be easily ventilated.

A peripheral edge recess can be provided on the front and/or the rear, in particular on the respective side, in particular in which the pre-channel structure gently tapers off or opens smoothly. The edge recess improves the venting because air can otherwise be trapped in the edge area without an edge recess when the cartridge is vented. The edge area preferably has an inner diameter and an outer diameter. The outer diameter corresponds in particular to the diameter of the piston. An edge area comprises, in particular without a scraper and/or without a recess, the inner diameter and the outer diameter. The pre-channel structure preferably opens at the inner diameter of the edge area, in particular as explained above in the edge recess. The edge recess can correspond to a venting groove. It can be further preferred if the edge recess extends at least partially to completely radially from the inner diameter to the outer diameter of the edge area and extends partially to completely, in particular circularly or with interruptions, in particular between the recesses of the pre-channel structure.

The diameter of the head side of the closure element preferably has at least 8 mm, preferably at least 10 mm. Furthermore, it is preferred if the diameter of the piston is greater than or equal to 20 mm and optionally less than or equal to 150 mm, in particular greater than or equal to 22 mm and optionally less than or equal to 100 mm. More preferably, the front side of the piston has a diameter of greater than or equal to 20 mm, in particular greater than or equal to 22 mm and optionally less than or equal to 150 mm. Particularly preferably, the inner diameter of the edge region of the front side of the piston has a diameter of greater than or equal to 20 mm, in particular greater than or equal to 22 mm and optionally less than or equal to 150 mm, in particular less than or equal to 100 mm.

The ratio of the diameter of the head side of the closure element to the diameter of the piston, in particular the diameter of the front side of the piston, more preferably the inner diameter of the edge region of the piston is from 1:2 to 1:10, preferably from 1:3 to 1:7, particularly preferably 1:5, in particular with plus/minus 25%, in particular plus/minus 10%, preferably plus/minus 5%. A ratio of the diameter of the closure element, in particular the diameter of the cover of the head side, to the diameter of the edge recess, in particular to the inner diameter, of 1:5 is particularly preferred, in particular with a standard deviation of plus/minus 5%. The head side of the closure element, in particular the cover of the closure element, can have a surface, in particular an end face, of 39 to 80 mm ² , preferably 45 to 55 mm ² , particularly preferably 50 mm ² , in particular a circular end face, preferably with a deviation of plus/minus 15%, preferably 5%.

The front side of the piston can preferably have a surface of greater than or equal to 200 to 300 mm ² , preferably from 220 to 270 mm ² , particularly preferably of 250 mm ² , in particular as a circular surface, preferably with a deviation of plus/minus 15%, preferred of 5%.

The front side of the piston is preferably a maximum of a factor of five larger, in particular at least a factor of 1.5 to 5 larger, preferably a factor of 3 to 5, preferably 4 to 5, than the surface of the head side of the closure element, in particular as the surface of the Lid of the closure element. Preferably, the front side of the piston, particularly preferably the area of the front side within the inner diameter of the edge region, is preferably larger by a maximum of a factor of five, in particular larger by a factor of 1.5 to 5, preferably by a factor of 3 to 5, preferably 4 to 5 , as the surface of the head side of the closure element, in particular as the surface of the lid of the closure element.

Furthermore, it may be preferred if the edge recess, in particular as a ventilation groove, has a width of 0.2 mm to 1 mm, preferably from 0.2 mm to less than or equal to 0.6 mm and/or a depth of less than or equal to 2 mm, in particular from 0.001 mm to less than or equal to 2 mm.

The pre-channel structure advantageously has a width of less than or equal to 0.6 mm, in particular from 0.001 to 0.6 mm, preferably from 0.2 to 0.6 mm and/or a depth of less than or equal to 2 mm, in particular from 0.001 mm to 2 mm, preferably from 0.01 to 2 mm. The pre-channel structure is preferably designed as a groove-shaped depression, in particular as an open groove-shaped depression. The pre-channel structure comprising the depressions, in particular groove-shaped depressions, can run from the center of the front side, in particular the recess and/or the countersink, to the edge region and in particular open into the edge depression of the edge region. The edge depression can be designed as a venting groove into which the depressions of the pre-channel structure open. It is further preferred if the entire area of the openings of the pre-channel structure, in particular the depressions of the pre-channel structure, and optionally the opening of the edge depression, for Total surface area of the piston, in particular the front side of the piston, preferably the total surface area of the piston with edge region and optionally with edge recess, particularly preferably up to the outer diameter of the edge region, is less than or equal to 6%, preferably from 0.0001 to 6%, preferably from 0.01 to 6%, more preferably from 0.01 to 5%. In particular, the pre-channel structure is designed in such a way that a typical cartridge content can only penetrate the pre-channel structure with difficulty or not at all, and in such a way that air can penetrate the pre-channel structure. This is preferably achieved by sufficiently narrow channel-shaped, slot-shaped and/or groove-shaped geometric elements in the pre-channel structure, into which a fluid that is too viscous or a pasty cartridge content can only penetrate with difficulty or not at all. Slot-shaped or groove-shaped recesses are therefore particularly advantageous for venting the cartridge, in particular as a pre-channel structure, but if necessary also or alternatively as a channel structure.

The pre-channel structure(s), in particular having depressions, can be arranged in a star shape on the front and/or on the rear of the piston. This is to be understood as meaning that the individual components of the pre-channel structure point outwards approximately starting from the central axis of the piston or the middle of the front/rear and are evenly distributed around the central axis or the middle.

It is preferred if radially, in particular spoke-shaped or star-shaped, from the center of the front, in particular from the recess and / or from the recess, at least two, preferably at least four, particularly preferably two to fifty, open to the outside, in particular towards the cartridge open, groove-shaped recesses are formed, which form the pre-channel structure and in particular extend to the edge region, and open in the edge region, in particular in the present case in an edge recess running around the front of the piston.

The same applies to the ventilation option(s), in particular having grooves or slots, which can be arranged in a star shape around the central axis, in particular in the channel structure. It can be assumed that the grooves or slots particularly preferably have the same structural design as depressions.

In a further preferred embodiment of the invention, it is provided that the closure element and/or the piston is made of one or more of the following materials: thermoplastic, elastomer, thermoplastic elastomer, duromer or duroplast. The piston is preferably made of a thermoplastic, such as polypropylene (PP), polyethylene (PE), mixtures of PP and PE or corresponding thermoplastics filled with inorganic fillers. The closure element can be made of a thermoplastic, preferably made from a thermoplastic elastomer (TPE) and/or has this/these. Typical thermoplastic elastomers include PP, PE or mixtures of these with latex or silicone. Examples are TPA (TPE-A), such as thermoplastic polyamide elastomers, TPC (TPE-E), such as thermoplastic copolyester elastomers, TPO (TPE-O), such as thermoplastic elastomers based on olefins, such as PP(EPDM), TPS (TPE-S), such as thermoplastic styrene block copolymers, TPU (TPE-U) thermoplastic elastomers based on urethane. The aforementioned polymers can be present as homopolymers, copolymers or also as block copolymers or as mixtures of these.

In particular, if the closure element is made of a material that is softer or more elastic than the piston, the sealing function can be achieved well in the closed position, and the locking or jamming of the closure element, in particular in the closed position, can also be further improved. Any configuration of the three features: "pre-channel structure", "channel structure" and "venting option" among the three features mentioned can be applied to any other feature of the three features.

The ventilation option and/or the pre-channel structure can, alternatively or additionally, be a component of the channel structure or of the recess or be a component of both. Therefore - when talking about the channel structure and/or the recess - reference can also be made to the ventilation option or the pre-channel structure. In other words, there may be a smooth transition or a transition that cannot be clearly defined between the recess (including recess), the channel structure, the pre-channel structure and/or the ventilation option.

According to an alternative, the closure element can be designed, at least essentially, to be rigid or inflexible. In particular, rigid or inflexible means that no significant and/or no design-related elastic deformability of the closure element is provided. Rigid or inflexible also implicitly and in particular also means that the closure element, at least essentially, always has an approximately identical functionality, regardless of the material, as long as the material used is designed to have closed pores. The closure element can therefore be made of metal, plastic or ceramic. This material-related idea arises from the fact that the listed materials, which differ greatly in their properties (density, hardness, modulus of elasticity, impact energy, etc.), are purely based on their geometry and not on the basis of their rigidity or . Flexibility, can function as a closure element. According to likewise preferred embodiments, the closure element can have a core made of a rigid material and a cover over the core made of flexible material. In a further alternative, the closure element is formed in one piece from an elastic, thermoplastic material, such as TPE. All sealing surfaces of the closure element and/or the piston are preferably made of elastic, thermoplastic material or are coated with it. A guide section, which also functions as a seal, can also be made of an elastic, thermoplastic material.

The closure element and/or the piston can each be manufactured as one, in particular one-piece component, preferably an injection-molded component.

In particular, the closure element can have a guide section. The guide section can be a section that is separate from other sections or parts of the closure element and/or runs around the central axis. However, the guide section can also be formed by several non-circumferential sections or locations on the closure element. In particular, the guide section can be at least substantially opposite the head side and/or end face. The guide section can in particular be adjacent to a taper of the reinforcing element, which facilitates insertion into the recess. The guide section of the closure element can be rigid or elastic. According to a preferred alternative, the closure element is formed in one piece from a thermoplastic elastomer. In a further alternative, the closure element can be formed in several parts and, for example, comprise a rigid core and optionally a rigid core in the head side, which is covered by elastic material, in particular an elastic thermoplastic.

A or the clamping force, in particular in the closed position, between the piston and the closure element can result from the fact that the closure element, in particular at the guide section, has an excess dimension compared to the recess. For example, when the closure element is inserted into the recess, the oversize results in static friction between the piston and the closure element, in particular in the area of the guide section, which must be overcome when adjusting the closure element.

A wiper can be provided all around one or the edge of the front and/or the rear side and/or on the outside for resting and sealing on an inner surface of a cartridge. The wiper can wipe off the inner surface of the cartridge. Several scrapers can also be provided. A sealing lip can also be provided as a scraper. The sealing lip can face the front or the rear. In particular, the wiper can run, at least essentially, parallel to and/or next to the sealing groove or seal.

A further proposal is that a cartridge, in particular an unfilled cartridge, preferably having a piston opening for a cartridge piston device, is provided together with a cartridge piston device. This allows a user to benefit from the advantages of the invention mentioned in the application, for example in that the user only needs to fill the cartridge and/or insert the piston provided with the closure element in the open position.

Due to the simple and reliable venting function of the proposed cartridge piston device or the cartridge, even very sensitive cartridge contents or impression materials can be stored in a cartridge because venting can be carried out particularly easily and quickly.

Any feature mentioned in the singular can also be used in the plural and produce synergistic benefits; Likewise, features mentioned in a plurality can advantageously be provided in a single number; This does not need to be explicitly referred to in individual cases. In particular - to give a non-exhaustive list - individual or several: ventilation options, pre-channel structures, channel structures, recesses, sealing surfaces, recesses, closure elements, end faces, head sides, back, securing sections, guide sections, sealing elements, tapers and so on can be provided. In particular, reference is made here to the list of reference symbols.

The invention further relates to a method for venting and closing a cartridge with a cartridge piston device. The cartridge piston device can have a piston having a channel structure and a closure element for closing the channel structure by inserting the closure element into a recess in the area of the front of the piston, which can be moved into a closed position by adjusting the closure element or can be designed according to the preamble of claim 1 or can be designed according to one of the remaining claims. The method can have the following method steps: a. Providing a cartridge, in particular a cartridge filled with cartridge contents, with a piston opening, b. Providing the cartridge piston device, in particular with the closure element inserted into the recess and/or in an open position, c. Inserting the cartridge piston device into the piston opening, wherein an open position is present, d. Venting the cartridge by inserting the cartridge piston device, wherein the closure element is held in place by the recess and/or can be or may strike in the pull-out direction, and, preferably, in particular venting the cartridge by inserting the cartridge piston device until the front side comes into contact with a cartridge content, preferably further inserting the cartridge piston until there is essentially no more air-filled volume between the piston content and the front side of the cartridge piston, wherein the cartridge piston is preferably inserted until the closure element is moved into the closed position by the cartridge content, in particular by the pressure of the cartridge content building up on the closure element, e. Closing the cartridge by moving the closure element into the closed position by contact of the cartridge content with the closure element and/or by applying force to the closure element, preferably during or after step d, in particular automatic or self-closing, and optionally f. preferably maintaining the closed position of the cartridge piston device.

In step e, the closure preferably takes place automatically or independently, in that the cartridge piston device is pushed into the cartridge filled with cartridge contents by a drive shaft in the direction of the medium and the closure element is pushed into the piston automatically by the force exerted by the cartridge contents (on the media side).

Individual features of the cartridge piston device or the cartridge are applicable accordingly to the aforementioned method and use. The advantages apply accordingly.

Furthermore, the invention relates to a kit comprising a cartridge and at least one cartridge piston device, in particular comprising one or two cartridge piston devices and a single-chamber or double-chamber cartridge. The invention also relates to a closure element for use with a piston, wherein in particular a piston with an inserted closure element forms a cartridge piston device, wherein the closure element has a head side with an end face, a rear side which is opposite the end face, and a sealing element. The head side is preferably designed as a cover, in particular as a cover with a planar rear side which is opposite the end face of the head side. The closure element comprises a head side, at least one sealing element, optionally a securing section, optionally a guide section, and optionally a taper and optionally a second guide section.

According to an alternative embodiment, the closure element has an opening on its head side, which extends from the end face to the back of the head side and is optionally guided through the closure element to the opposite end of the closure element, in particular the opening on the back of the Closure element have at least three elements, each of which has at least one sealing surface, preferably at least two sealing surfaces, which are formed from the outer circumference of the elements towards the opening and by external force on the outer surfaces of the elements, the sealing surfaces of the elements come to lie on one another and thereby close the opening on the side of the closure element facing away from the end face.

The at least three elements, in particular in the initial position or the open position in the piston, have an approximately cylindrical circumference, and in particular in the closed position after insertion into a conical recess in the piston, the sealing surfaces of the elements come into contact with one another and close the opening in a fluid-tight manner, especially in the closed position.

In this embodiment, the piston has a cylindrical recess that runs from the front to the inside of the piston and from there at least partially conically to the rear. The protruding closure element can be inserted into this recess and, when inserted into this recess, closes the recess and the opening of the closure element for fluid passage; in particular, the closed position is present.

The invention also relates to a piston for insertion into a cartridge, which has a front side, a rear side facing away from the front side, an outer side with a circumferential sealing groove and/or seal for circumferential sealing on an inner surface of the cartridge, with a recess in the area of the front side for insertion a closure element in an insertion direction, and optionally a channel structure fluidically connecting the recess and the rear side for venting the cartridge, and the piston in the direction of the front side has a support surface formed substantially perpendicular to the central axis of the piston, in particular in a recess on the front side of the piston, for the rear side of the closure element, which is opposite the end face of the closure element.

Furthermore, the object is achieved by using a cartridge piston device for insertion into a cartridge and closing the back of this cartridge. The cartridge piston device has a piston with a channel structure and a closure element for closing the channel structure by inserting the closure element into a recess in the piston and by adjusting the closure element to a closed position, or is particularly designed according to the preamble of claim 1 or according to one of claims 1 to 10. Closing the cartridge involves adjusting the closure element to the closed position, wherein the adjustment takes place through contact of one and/or the cartridge contents with the closure element and/or through the introduction of force onto the closure element.

The invention is explained below by way of example with reference to the accompanying drawings using preferred exemplary embodiments, whereby the features shown below can represent an aspect of the invention both individually and in combination. Show it:

Fig. 1A-C: a cartridge piston device inserted into a cartridge filled with cartridge contents before venting in an open position (Fig. 1 A), during venting (Fig. 1 B) and after venting in a closed position (Fig. 1C) in a partially sectioned side view,

Fig. 2: a closure element in a side view,

Fig. 3A: a piston in a top view,

Fig. 3B: another piston in a partial top view, Fig. 4A: the cartridge piston device, consisting of the closure element and the piston of Fig. 2 and Fig. 3A, with the closure element inserted into a piston in an open position in a partially sectioned side view,

Fig. 4B: the cartridge piston device of Fig. 4A with the closure element in a closed position in a partially sectioned side view, and

Fig. 5A-C another cartridge piston device according to the invention in a view from the rear (Fig. 5A), from the outside (Fig. 5B) and from the front (Fig. 5C).

In Fig. 1A-C, a cartridge piston device 1 with a piston 2 and a closure element 3 is shown, which is inserted or pushed into a cartridge 4. The cartridge 4 is filled with cartridge contents 5, a highly viscous or pasty mass, and is at least substantially cylindrical. One or the front side 7 of the piston 2 faces the cartridge contents 5, with one or the opposite rear side 8 of the piston facing away from the cartridge contents 5. Not shown, but it is also possible that the rear side 8 of the piston 2 faces the cartridge contents 5 or comes into contact with the cartridge contents 5.

The piston 2 seals at the contact points with an inner surface 6 of the cartridge 5 in the area of the outer side 9 of the piston 2 all the way around by means of a seal 13 designed as an O-ring inserted into a sealing groove 12. Furthermore, scrapers 14, which are in contact with the inner surface 6, ensure that no - or at least essentially no - cartridge contents 5 come into contact with the seal 13. The closure element 3 in Fig. 1A is guided and received axially in an open position relative to the piston 2 and in a recess 11 of the piston 2, whereby a fluidic connection is possible via the recess 11 via a channel structure 10 in the piston from the front side 7 facing the cartridge contents 5 to the rear side 8 facing away from the cartridge contents. Via the fluidic connection present in the open position, a possibly remaining cavity 34 can be vented when the piston 2 with the closure element 3 is displaced or adjusted along a central axis 15 in the cartridge, in particular as long as the closure element 3 is not in contact with the cartridge contents 5.

In Fig. 1B, the closure element 3 is in contact with the cartridge contents 5 via its head side 17, which has a front surface 16, and is still in the open position. In this position, any further adjustment of the cartridge piston device 1 along the central axis 15 (see Fig. 4A) of the cartridge 4 in the direction of the cartridge contents 5 causes a Force is applied to the closure element 3 in the axial direction or in an insertion direction 18 of the closure element 3 relative to the piston, since the cartridge contents 5 offer resistance to the penetration of the closure element 3. Since the force on the cartridge piston device 1 for inserting the cartridge piston device 1 into the cartridge 4 is typically applied to the rear side 8 of the piston 2, the force applied to the closure element 3 by the cartridge contents 5 will gradually lead to an increase in pressure in the area of the cartridge contents 5 and to an adjustment of the closure element 3. The closure element 3 can then be adjusted from the open position shown in Fig. 1B to a closed position shown in Fig. 1C, in particular if the force is applied large enough.

Because adjusting the closure element 3 in the piston 2 or in the recess 11 requires a certain amount of force to be introduced (because the closure element is guided and held fixed or clamped via a guide section 20), further venting of the cartridge 4 will first take place before the closure element 3 can at least approximately reach the closed position. Thus, in the transition from the state of Fig. 1B to Fig. 1C, both a flow or deformation of the pasty cartridge contents 5, in particular around the closure element 3 or the head side 17 (see Fig. 1A) and/or on the front side 7, and a subsequent adjustment of the closure element 3 to the closed position will take place. The closure element 3 in the closed position, as shown in Fig. 1C, means that no fluid can pass from the cartridge contents 5 or the front side 7 to the rear side 8 of the piston, because the channel structure 10 in the piston is fluidically sealed by sealing the closure element 3 in the piston or in the recess 11. The closure element 3 is immersed in a recess 21 in the piston 2 and still protrudes slightly from the front side 7.

Fig. 2 shows a single closure element 3 of a further cartridge piston device 1 according to the invention. The closure element 3 is designed symmetrically about its central axis 22. A cylindrical head side 17 with a flat end face 16 is arranged on an outer side of the closure element 3 along the central axis 22. The end face 16 is arranged transversely, or more precisely perpendicularly, to the central axis 22. A sealing auxiliary element 23 is arranged all around the head side 17, adjacent to the end face 16, which is designed as a sealing lip 23 in this case. The sealing auxiliary element 23 can seal all around, for example in a recess 21. A sealing element 24 designed as a cone 24 adjoins the rear side 49, opposite the front surface 16 of the head side 17. The sealing element 24 is designed to be circumferential around the central axis 22 and optionally convex. The sealing element 24 is reminiscent of the shape of a countersunk head. Not shown is a sealing element 24 that is at least essentially circumferential and cylindrical (here: instead of conical) and/or has at least one sealing ring or O-ring.

Furthermore, the closure element 3 has a securing section 25, which is designed as a recess 25 running around the central axis. A securing means 26 (see Fig. 4A) or a snap ring 26 (see Fig. 4A) or also a retaining ring can engage in the recess 25 and abut axially.

The closure element 3 has a guide section 20, which in this case adjoins the securing section 25. The guide section 20 is designed such that it can be inserted into a recess 11 and is suitable for guiding the entire closure element 33 (see Fig. 4A), for example along the central axis 22. For this purpose, the guide section 20 is designed to be circumferential and preferably at least partially cylindrical around the central axis 22.

What is not shown is that one or the guide section 20 can alternatively or additionally be arranged at another axial location on the central axis 22 (a different location than in Fig. 2, for example) of the closure element 3. For example, the guide section 20 can also adjoin the sealing element 24 or the head side 17. What is not shown and is also possible is that several guide sections 20 are provided.

The closure element 3 has a taper 27, which in the present case is designed in the shape of a truncated cone or a truncated cone section (ie as a truncated cone or a truncated cone section). The taper 27 helps when inserting the closure element 3 into a corresponding recess 11 (not shown in FIG. 2) for the closure element 3. Because the taper 27 and optionally a second guide section 58 in the present case adjoins the guide section 20 and basically that of the head side 17 forms the opposite end of the closure element 3, the closure element 3 can be inserted with the taper 27 first into the corresponding recess 11 and brought into a guided position directly via the guide section 20. The corresponding recess 11 (not shown in FIG. 2) has a radius 28 in at least one section, which at least essentially corresponds to the radius 30 of the guide section or is minimally smaller (ie by up to 0.1%, 1% or 5%) than this. The one opposite The back side 49 of the head side 17 lying relative to the end face 16 can also act as a sealing surface. The taper 27 can be followed by a second guide section 58, which can serve to center the closure element in the insertion direction.

The illustrated and preferred closure element 3 is preferably designed as an injection molded component, which was produced, for example, by means of an at least two-part injection molding tool (not shown). The at least two-part injection molding tool can move open and close transversely to the central axis 22 of the closure element 3, in particular because the contour of the closure element 3 has no undercut along the central axis 22 and/or is rotationally symmetrical about the central axis 22.

Fig. 3A shows a piston 2 according to the invention with a recess 11 in the area of a front side 7 for inserting the closure element 3 in the insertion direction 18 (in the plane •). The piston 2 is round and essentially cylindrical, with the recess 11 being arranged centrally on a central axis 32 of the piston 2. The insertion direction 18 lies on the central axis 32 and points into the plane shown or is perpendicular to it. The recess 11 is basically formed by a bore with different diameters in sections in the piston 2. The recess 11 has a conical sealing surface 33 which corresponds to the sealing element 24 of the closure element 3 of Fig. 2, which is designed as a cone 24. The recess 11 also has an essentially cylindrical recess 21. The recess 21 corresponds to the end face 16 of the closure element 3 of Fig. 2.

Recesses, in particular sixteen recesses 35, of a pre-channel structure 35 extend in a star shape from the center of the front side 7 to the edge region 36 of the piston, where the recesses 35 open into a circumferential edge recess 37. The depressions 35 are slot-shaped or groove-shaped, i.e. designed as slots and/or grooves. In the present case, the depressions 35 are each several times deeper (into the plane shown) than the depressions 35 are wide, in particular by two to twenty or even thirty times or any multiple in between.

In the present case, the depressions 35 near the central axis 32 are also deeper than further away from the central axis 32. Adjacent to the depression 21, a single depression 35 is twice as deep (there is a depth 38 there) than at its end facing away from the central axis , where the depression 35 has the greater depth 39. In the present case there is a slope of the depth 38, 39 of the recess 35 rising from the edge region 36 up to the recess 11. The depths 38, 39 are at least approximately adjacent to one End of an individual depression 35 to measure, for example a maximum of 10% or 5% or 2% distanced from the end based on the total length of the individual depression 35.

In the edge region 36 of the piston 2, at the end of the recesses 35 facing away from the central axis 32 or near the outside 9, the edge recess 37 running around the front 7 is provided, into which the recess 35 in the present case also tapers off gently or continuously ends. The width 40 of the pre-channel structure 35 or depression 35 is at least approximately constant.

7 grooves or slots 41 of a ventilation option 41 extend in a star shape from the center of the front side from the recess 11 or also from a channel structure 10 of the piston 2 adjacent to the recess 11 at a deeper level. There are eight slots or slots 41 intended. The components of the ventilation option 41 are designed as slots 41 and/or grooves 41 and run at least essentially parallel to the recess 11 and the channel structure 10, i.e. into the plane shown. In the present case, the ventilation option 41 has an at least essentially similar or the same depth 42 and width 43 as the pre-channel structure 35.

Not shown are the following preferred design options for the venting option 41 for good fluidic permeability with regard to venting and the worst possible fluidic permeability of, in particular, pasty cartridge contents 5. The depth 42 and / or width 43 is preferably chosen to be constant, with an on at the end of the venting option 41 - or outlet with different depths 42 and widths 43 can be provided. For example, the depth 42 can be selected in the range from 0.1 mm to 5 mm or in the range from 0.5 mm to 3 mm, in particular in the range from 1 mm to 2 mm. The width 43 can be selected in the range from 0.01 to 2 mm or in the range from 0.05 to 1 mm, in particular in the range from 0.1 mm to 0.5 mm.

In Fig. 3A (but also Figs. 1A-C and 4A-B), a wiper 14 designed as a sealing lip is provided on the piston all around the edge of the front side 7 and the rear side 8, which removes the cartridge contents 5 from an inner surface 6 of a cartridge 4 can be stripped off because it has an at least circumferentially linear end face and can lie tightly against an inner surface 6 or can even lie pressed against it. The wiper 14 can be slightly pressed in resiliently in the direction of the central axis 32 all around the central axis 32. The wiper 14 on the front 7 points towards the front 7 or away from the rear 8. The wiper 14 on the back 8 points towards the back 8 or away from the front 7. The piston 2 shown in FIG. 3B is only further developed compared to the piston 2 of FIG. 3A in that four edge-side projections 49 are provided on the edge of the recess 21. The projections 49 can correspond to corresponding recesses 23 (not shown) on the closure element 3 or on its head side 17. The recesses 23 can be provided, for example, at the location/in the area of the auxiliary sealing element 23 and/or as and/or in addition to the auxiliary sealing element 23 on the closure element 3. The recesses 23 can be provided circumferentially and/or distributed on the head side 17 and/or correspond to the projections 49.

Not visible in Fig. 3A-B, but present, is a rear side 8 of the piston 2, which is arranged parallel to the front side 7, facing away from the front side 7 of the piston shown. An outside 9 of the piston 2 is provided all around the front 7 and the rear 8. The outside 9 is intended in particular for circumferential sealing on an inner surface 6 (not shown) of a cartridge 4 and has a (not visible) sealing groove 12 with a seal 13 for this purpose.

4A shows the closure element 2 of FIG. 2 inserted into the piston of FIG. 3A, whereby the cartridge piston device 1 is completed or assembled. The cartridge piston device 1 is further inserted into a cartridge 4 filled with cartridge contents 5, with the front side 7 of the piston 2 facing the cartridge contents 5 and spaced from the cartridge contents 5, so that an air-filled cavity 34 remains. The recess 11 has the present cylindrical recess 21 with a further sealing surface 47, the conical sealing surface 33 and the securing means 26 designed as a snap ring 26. There is a smooth transition from the recess 11 to a channel structure 10 fluidly connected to the recess 11 because the channel structure 10, at least essentially, has the same radius 29 or diameter or cross section as a section of the recess 11 as radius 28 or .Diameter.

4A is in an open position relative to the piston 2, the cross section of the channel structure 10 being essentially fluidically blocked due to the guide section 20, but with the ventilation option 41 designed as a groove 41 for a fluidic passage on the closure element 3 over ensures. The closure element 3 is arranged in the open position shown to be adjustable in a closed position that fluidically closes the channel structure 10, because this Closure element 3 can be displaced relative to the piston to the right (along the central axes 15, 22, 32 and in the insertion direction 18) in FIG. 4A.

To provide the open position in the recess 11, the closure element 3 of FIGS. 4A-B can abut against a securing means 26 designed as a snap ring 26 in the pull-out direction 19 with the securing section 25. The securing means 26 is inserted into a groove running around the central axis in the area of the recess 11.

The closure element 3 of FIGS. 4A-B is held fixed in the open position in the recess 11 due to a clamping in the area of the guide section 20 in order to provide the open position. The closure element 3 can be subjected to a force in the insertion direction 18 via the end face 16 of the closure element 3, which is oriented transversely to the central axes 22, 32 of the piston 2 and the closure element 3. The insertion direction 18 points to the rear side 8 of the piston 2 and in the present case runs parallel to the central axes 15, 22, 32.

A pull-out direction 19 is arranged opposite to the insertion direction 18. When the closure element 3 is moved in the insertion direction 18 relative to the piston 2, the head side 17 dips into the recess 21 and the auxiliary sealing element 23 comes into contact with the edge of the recess 21, on which a further circumferential sealing surface 47 is arranged, and seals there; furthermore, a gap 44 between the head side 17 and the bottom of the recess 21 narrows, via which a fluidic passage to the recess 11 and to the channel structure 10 for venting is ensured.

4A-B it can be seen that the pre-channel structure 35 is less deep near the outside 9 or in the edge region 36 than near the recess 21. This improves the ventilation function and the manufacturability because the pre-channel structure 35 is so can clog less quickly and because a lower average aspect ratio (depth/width) of grooves is generally easier to manufacture.

The outer side 9 is provided with a sealing groove 12 running around the outer side and a seal 13 contained in the sealing groove 12. The seal 13 is an O-ring 13 in the present case. On the outer side 9 in the edge areas 36, scrapers 14 are provided which are intended to prevent cartridge contents 5 from escaping by scraping against the inner surface 6 of the cartridge 4, in particular by the scrapers 14 being pressed against the inner surface 6 all the way around. The piston 2 has a diameter 45 of 60 mm +/- 6 mm in this case. Not shown, but also possible are diameters 45 in the range from 10 mm to 200 mm or any whole number of diameter 45 in between. The diameter is usually selected depending on the diameter of a corresponding cartridge 4.

The piston has a thickness 46 of 15 mm +/- 1.5 mm. Not shown, but also possible are thicknesses 46 in the range from 5 mm to 100 mm or any integer individual value of the thickness 46 in between. The selected thickness 46 depends largely on which material is used, which diameter 45 is used and what resistance to deformation the cartridge contents 5 offers.

The pre-channel structures 35 have a width 40 of 0.2 +/- 0.15 mm. The depth 38, 39 of the pre-channel structures 35, measured along the central axis 32 of the piston 2 and measured from the plane of the front side 7 of the piston 2, measures at one end of 4 mm +/- 1 mm as a depth 39 in the edge region 36 or near the outside or the edge recess 37, up to 2 mm +/- 0.5 mm at the other end, i.e. near the recess 21, as depth 38.

4B shows the cartridge piston device 1 of FIG. 4A in a closed position, with the cartridge contents 5 having pressed the closure element 3 into the closed position. The closure element 3 is pushed along the central axes 15, 22, 32 in the insertion direction 18 until the back of the head side 17 stops on the bottom of the recess 21 and until the sealing element 24 stops on the sealing surface 33. The sealing element 24 seals on the sealing surface 33 against a fluidic passage along the closure element through the recess and through the channel structure. In addition, the sealing auxiliary element 23 or the sealing lip 23 in the recess 21 seals circumferentially around the end face 16 in the recess 21 on a further circumferential sealing surface 47. The annular gap 44 between the head side 17 and the bottom of the recess 21 is closed or (temporarily) not present. The securing means 26 is located in the securing section 25, but does not strike against the securing section 25, but in this position is only designed or capable of striking against the securing section 25 in the extension direction 19.

In Fig. 4B, the cartridge contents 5 are also shown, which push the closure element 3 into the closed position when the cartridge piston device 1 is pushed in (with the adjustment element 3 originally in the open position, not shown) over the front surface 16. Recess 11 was pressed or adjusted. This resulted in the venting of the cartridge 4 or an escape of air from the cavity 34 of the cartridge 4 by means of the pre-channel structure 35, via the gap 44, via the venting option 41 past the closure element 3 and out of the channel structure 10 of the piston 2 at the rear side 8, until finally - as shown - the closed position was or is present.

What is noteworthy in FIG. 4B is that the cartridge contents 5 have penetrated into the pre-channel structures 35 despite their high viscosity and despite the narrow width or the high aspect ratio of the pre-channel structures 35. The advantage here is that the penetration through the depth 38, 39 of the pre-channel structures 35, which increases from the outside to the inside, also took place from the outside to the inside, so that the air to be removed from the cavity 34 has been gradually and completely removed.

Not shown is an embodiment of a cartridge piston device 1 in which no pre-channel structures 35, in particular none on the front 7, are provided.

In Fig. 1A-C and 4A-B, the cartridge 4 shown in each case has a piston opening 48 on the rear side, into which the cartridge piston device 1 can be axially inserted and is inserted. On the side opposite the piston opening 48 (front side), but in particular at the remaining points of the cartridge away from the piston opening 48, no further piston opening is shown in the present case, although this is typically provided.

1 A-C show, the cartridge 4 also has a front valve 49 as a further piston opening, in particular for removing the cartridge contents 5.

In particular, a further piston opening and/or a valve 49 are/is generally arranged, in particular on the front side of the cartridge 4 and/or provided for using the filled, vented and closed cartridge 4, typically because the cartridge contents 5 are to be pressed out of the cartridge when the cartridge piston device 1 or the piston 2 is pushed in further.

In Fig. 5A-C, a further embodiment of a cartridge piston device 1 according to the invention is shown in different views. The head side 17 of the closure element 3 is designed as a cover 17B, in particular with the diameter 17A of the head side of the closure element. The cartridge piston device 1 shown in Fig. 5A-C is for insertion into a cartridge 4 and for venting and rear closure of the cartridge 4. Fig. 5A shows a piston 2 from its rear side 8, wherein a closure element 3 on a front side 7 facing away from the rear side 8 (see Fig. 5C) is inserted into a recess 11 in the region of the front side 7 (see Fig. 5C) and can be seen through a channel structure 10 located centrally on a central axis 22, 32. More precisely, a taper 27 of the closure element 3 can be seen, which in this case is designed as a truncated cone section 27. The closure element 3 is in an open position, so that a fluidic passage or a fluidic connection, in particular for venting a cartridge 2, is possible from the rear side 8 through the channel structure 10 past the closure element 3 to the front side 7. The rear side 8 (or also the front side 7, which is not visible) is encircled or surrounded by an outer side 9; in other words, the outer side 9 surrounds the rear side 8 as well as the front side 7 (see Fig. 5C).

Fig. 5B shows the cartridge piston device 1 from the side or outer side 9. On the outer side 9 there is a sealing groove 12 and in it a seal 13 or an O-ring 13 for circumferential sealing on a cartridge wall (not shown) or an inner surface 6 of a cartridge 4. The seal 13 protrudes radially from the outer side 9. In addition, two scrapers 14 are arranged on the outer side 9, which can rest on a cartridge wall or inner surface 6 of a cartridge 4 and can be elastically pressed in radially. The two scrapers 14 are located in the area of the outer side 9 located on the front side 7 and face the front side 7 or point in the direction of the front side 7; opposite or in the area located on the rear side 8, the outer side 9 is at least substantially cylindrical. The closure element 3 protrudes from the front side 7 because it is arranged in the open position. The closure element 3 is arranged so as to be adjustable in an insertion direction 18, which points from the front side 7 to the rear side 8, into a closed position that fluidically closes the channel structure 10. In order to provide the open position, the closure element 3 is held in a force-fitting manner in the open position by clamping by means of its guide section 20 (not visible) in the recess 11. The closure element 3 also strikes a securing means 26 in the recess 11 in the pull-out direction 19 by means of its securing section 25 (not visible in Fig. 5A-C).

Fig. 5C shows the cartridge piston device 1 with a view of the front side 7, wherein the closure element 3 is inserted in the recess 11 and is in the open position. On the closure element 3 and at least substantially parallel to the front side 7 there is a flat, round front surface 16; the front surface 16 is part of a cylindrical Head side 17 of the closure element 3. Between the head side 17 and a round recess 21 arranged centrally on the front side 7, which is cylindrical and corresponds to the head side 17, in particular the front face 16 and/or the back (the recess 21 is completely covered by the head side 17 in the illustration in Fig. 5C), a gap 44 which is at least substantially parallel to the front side 7 (which is also covered) is formed in the open position shown. A sealing auxiliary element 23 which is designed as a sealing lip 23 is also arranged all around the head side 17, adjacent to the front face 26. The sealing auxiliary element 23 can seal all around in the recess 21, in particular in a closed position of the closure element 3 (not shown).

In the closed position (not shown), the gap 44 is closed or no longer present. In the closed position, in an alternative, the closure element 3, in particular the head side 17, does not protrude from the front side 7 and is flush with the front side 7 or is recessed into the front side, in particular because the closure element 3 has been pressed into the piston 2 along the insertion direction 18.

Radially, in particular spoke-shaped or star-shaped, from the center of the front side 7, in particular from the recess 11 and/or from the countersink 21, at least two, preferably at least four, particularly preferably two to fifty outwardly open groove-shaped depressions 35 open towards the cartridge 4 (not shown) extend and form the pre-channel structures 35 up to the edge region 36, and in particular in the present case open into an edge depression 37 running around the front side 7. Radially, in particular spoke-shaped or star-shaped, from the center of the front side 7, in particular from the recess 11 and/or from the countersink 21, in Fig. 5C, twenty-four outwardly open groove-shaped depressions 35 or pre-channel structures 35 open towards the cartridge 4 (not shown) extend up to the edge region 36, and in particular in the present case open into an edge depression 37 running around the front side 7. In principle, the depressions 35 can also extend from the center the front side 7, in particular the recess 11 and/or the depression 21, extend into the edge region 36 and have any shape, such as, for example, serrated, jagged, ladder-shaped and/or herringbone pattern, etc. The depressions 35 are arranged at least approximately over the entire surface and distributed on the front side 7, so that ventilation can be carried out over a large area. In the vicinity of the edge region 36 of the front side 7, the pre-channel structures 35 are twice as deep (depth 39 is 4 mm there) as in the vicinity of the depression 21 (depth 38 is 2 mm there). The pre-channel structures 35 have a width 40 of 0.2 mm, in particular from 0.2 mm to 1 mm, preferably less than or equal to 0.6 mm. All around the One of the scrapers 14 can be seen on the front side 7. The pre-channel structures 35 are located on the front side 7, although an arrangement on the rear side 8 is also possible as an alternative or in addition. The pre-channel structures 35 here fluidically connect the front side 7 with the recess 11, with the channel structure 10 and with the rear side 8.

The piston 2 of Fig. 5A-C is at least substantially cylindrical (“at least substantially” because the scrapers 14 and the circumferential sealing groove 12 or seal 13 cause the outer contour to deviate from a cylindrical shape).

The piston 2 and the closure element 3 of FIGS. 5A-C are here parts manufactured by injection molding. The closure element 3 is made of a softer material (in particular a polymeric material) than the material of the piston 2 (in particular a polymeric material). In the present case, the closure element 3 is made of a thermoplastic elastomer and the piston 2 is made of a polyethylene, although alternatively or additionally a polypropylene (or other plastic) is also possible. These or other polymers or plastics can be used as materials for all parts mentioned in this application.

The cartridge piston device of Fig. 6A.1 to 6C is shown in Fig. 6A in the open position and in Fig. 6B in the closed position. The closure element 3 is inserted into the piston 2. In the open position, the head side 17 protrudes from the front of the piston, Fig. 6A.1 and Fig. 6A.2. The delivery-side rear side 8 of the piston 2 is shown in Fig. 6A.1 and Fig. 6A.2. The piston has openings 53 for venting in the support surface 51 for the rear side 49 of the head side of the closure element.

The head side of the closure element is designed as a cover 50. The cover has the end face, which is designed as a seal 56, and a back 49, which is also designed to seal the openings 53, see FIG. 6C, in that the back can close the support surface 51 for the back in a fluid-tight manner. The support surface 51 can be designed as a sealing surface 33. Due to the diameter of the head side of the closure element, it can be closed automatically by the action of force on the media side, in that a drive shaft of a mixer conveys a medium on the delivery side. In the open position, the groove 52, which runs at least partially to completely around the head side, is fluidly continuous and the air can escape through the openings 53 and optionally the channel structure. In the closed position, the groove 52 is fluidically closed by the seal 56, Fig. 6B.1. The piston also has a sealing lip 55 running around the outer circumference. In Fig. 6C the piston is in a top view of the bearing surface of the rear 51, which represent the openings 53 and the pre-channel structure 35 as well as a centering 54 towards the rear of the piston.

The cartridge piston device of Fig. 7A to 7E is shown in Fig. 7A in the open position and in Fig. 7B in the closed position. The closure element 3 is inserted into the piston 2. In the open position, the head side protrudes from the front of the piston, Fig. 7A. The delivery-side rear side 8 of the piston 2 is shown in Fig. 7A. The piston has the support surface 51 as shown in Fig. 7C for the rear of the head side of the closure element. The closure element has a taper as a securing section 25 and a guide section 20. The sealing surface in the recess of the piston 33 is shown in Fig. 7A. The sealing surfaces 33 and the conical seal 24 lie against one another in the closed position and seal the cartridge piston device fluidically tightly. The head side 17 of the closure element 3 is designed as a cover 17B. Due to the diameter 17A of the head side of the closure element, this can be closed automatically by the application of force on the media side, in that a drive shaft of a mixer conveys a medium on the conveying side. In the open position, the groove 52, which runs at least partially to completely around the head side, is fluidically permeable and the air can escape along the closure element through the channel structure 10. In the closed position, the channel structure 10 is fluidically closed by the sealing element in the form of a conical seal 24, Fig. 7B. The piston also has a sealing lip 55 running around the outer circumference. The foot side is shown as 62. In Fig. 7C, the piston is shown in a plan view of the support surface of the rear side 51, which represents the pre-channel structure 35 and a centering 54 in the direction of the rear side of the piston.

Figures 7D and 7E show the open and closed positions of the cartridge piston device comprising a piston 2 and a closure element 3 (7D open, 7E closed). The figures also showed air access elements or radial grooves 57, which are on the outside of the piston around the head side of the closure element.

The channel structure (not shown) with pre-channel structure 35 (Fig. 7C) preferably runs from the recess radially in the direction of the outer circumference of the piston. Particularly preferably, the channel structure comprising a pre-channel structure runs from the recess radially at least partially outwards in the direction of the outer circumference of the piston, wherein the pre-channel structure is arranged in the support surface 51 of the piston. In the closed position, the support surface of the piston comes into contact with the rear side of the closure element, preferably the rear side of the closure element rests on the support surface, preferably in a fluid-tight manner. The cartridge piston device of Fig. 8A to 8C is shown in Fig. 8A in the open position and in Fig. 8B in the closed position. In the closed position, the head side of the closure element is essentially pushed into the piston. The closure element 3 is inserted into the piston. In the open position, the head side protrudes from the front of the piston, Fig. 8A.1, 8A.2. The delivery-side rear side 8 of the piston is shown in Fig. 8A. The piston has the support surface 51 as shown in Fig. 8C for the rear of the head side of the closure element. The closure element has a taper as a securing section 25 and a guide section 20. The sealing surface in the recess of the piston 33 is shown in Fig. 7A. The sealing surfaces 33 and the cylindrical seal 24 lie against one another in the closed position and seal the cartridge piston device fluidically tightly. The head side 17 of the closure element is designed as a cover 17B. Due to the diameter 17A of the head side of the closure element, this can be closed automatically by the application of force on the media side, in that a drive shaft of a mixer conveys a medium on the conveying side. In the open position, the groove 52 that runs at least partially to completely around the head side is fluidically permeable and the air can escape along the closure element through the channel structure 10. In the closed position, the channel structure 10 is fluidically closed by the sealing element in the form of the cylindrical seal 24, Fig. 8B. The piston also has a sealing lip 55 that runs around the outer circumference. In Figs. 7B and 7C, the piston is shown in a top view of the support surface of the rear side 51, which represents the pre-channel structure 35 and a centering 54 in the direction of the rear side of the piston. Figures 8A.2 and 8B.2 show the open and closed positions of the cartridge piston device comprising a piston and a closure element 3 (8A.2 open, 8B.2 closed). The figures also show air inlet elements or radial grooves 57 which are located on the outside of the piston around the head side of the closure element.

Figures 9a to 9c show an alternative embodiment of a closure element 3 in a piston 2, in which the closure element 3 has an opening 61 on its head side. The opening 61 extends from the front face to the back of the head side and is guided through the closure element to the opposite end of the closure element, in particular to the foot side 62 of the closure element. The closure element has at least three elements 59 on the back opposite the front face, 4 to 6 or more elements are also possible, each of which has at least one sealing surface 60, preferably two sealing surfaces 60, which are formed from the outer circumference of the elements 59 to the opening 61. By external force acting on the outer surfaces of the Elements 59, the sealing surfaces 60 of two adjacent elements 59 come to rest on one another and close the opening 61 of the closure element on the side facing away from the end face. The opening in the closure element preferably lies on and/or parallel to the longitudinal center axis of the closure element. The embodiment corresponds to a closure element with conical gaps, which is formed by the elements with sealing surfaces.

Reference symbol list

1 cartridge piston device

2 pistons

3 Locking element

4 cartridge

5 Cartridge contents

6 inner surface (of the cartridge)

7 Front (of the piston), cartridge side

8 Rear side (of the piston), delivery side

9 Outside (of the piston)

10 Channel structure

11 recess

12 sealing groove

13 Seal, O-ring

14 scrapers

15 central axis (of the cartridge)

16 Front face, cartridge or media side

17 head page

17A diameter of the head side of the closure element 3

17B lid, in particular with a diameter 17A of the head side 17 of the closure element

18 insertion direction

19 Extraction direction

20 Guide section

21 Countersinking (of the recess)

22 Central axis (of the closure element)

23 Auxiliary sealing element, sealing lip

24 Sealing element (of the closure element), cone

25 safety section, taper

26 Safety device, snap ring

27 taper, truncated cone, truncated cone section Radius (of the recess) Radius (of the channel structure) Radius (of the guide section) Diameter (of the guide section) Central axis (of the piston) Sealing surface (of the recess) Cavity Pre-channel structure Edge area (of the piston) A inner diameter edge area, in particular without edge recessB outer diameter edge area edge recess ( of the piston), circumferential edge recess (of the piston) Depth (of the pre-channel structure) Depth (of the pre-channel structure) Width (of the pre-channel structure) Venting option, groove, slot Depth (of the venting option) Width (of the venting option) Gap Diameter (of the piston) Thickness (of the piston ) Further sealing surface (on the recess) Piston opening on the back opposite to the end face Cover support surface on the back Groove Openings Centering Sealing lip(s) Sealing auxiliary element, seal, protruding sealing lip Air access element or radial groove Second guide section Elements with at least two sealing surfaces (60) Sealing surfaces Opening of the closure element on the foot side

Claims

Claims Cartridge piston device (1) for insertion into a cartridge (4) and for venting and closing the rear of the cartridge (4), with a piston (2), and with a closure element (3) for insertion into the piston (2), wherein the piston (2) has

- a front side (7),

- a rear side (8) facing away from the front,

- an outer side (9) with a circumferential sealing groove (12) and/or seal (13) for circumferential sealing on an inner surface (6) of the cartridge (2), characterized in that

- the piston has a recess (11) in the region of the front side (7) for inserting the closure element (3) in an insertion direction (18), and

- a channel structure (10) fluidically connecting the recess (11) and the rear side (8) for venting the cartridge (2), and

- an insertion direction (18) pointing at least substantially from the front side (7) to the rear side (8) and an extraction direction (19) opposite to the insertion direction (18), in particular for the closure element, wherein the closure element (3) which can be inserted into the recess (11) or at least a part of the closure element (3) which can be inserted into the recess (11) can be arranged in an adjustable manner in the insertion direction (18) from an open position which fluidically releases the channel structure (10) into a closed position which fluidically closes the channel structure, wherein the closure element has a head side (17) with an end face (16) and a sealing element, wherein the closure element (3) can be fixed in the open position in the recess (11) to provide the open position and/or at least abuts in the extraction direction (19), and the piston in the direction of the front side has a support surface which is designed substantially perpendicular to the central axis of the piston for the rear side (49) of the closure element, which End face (16) of the closure element. Cartridge piston device according to claim 1, characterized in that the piston has a support surface in the direction of the front side, which is formed substantially perpendicular to the central axis of the piston, in a recess formed on the front side for the rear side of the closure element, which is opposite the end face of the closure element. Cartridge piston device according to claim 1 or 2, characterized in that the closure element (3) has a head side (17) having an end face (16), and, preferably, wherein

- At least in the open position, the end face (16) protrudes from the front (7), and / or between the head side (17), in particular the back (49), and the piston (2), in particular a recess (21) of the Piston, a gap (44) which opens fluidly into the recess (11) is formed, and/or

- at least in the closed position, the end face (16) is at least substantially flush with the front face (7) or is recessed in the front face (7), in particular wherein the head side () is recessed further than in the open position. Cartridge piston device according to claim 3, characterized in that the head side (17) and/or the end face (16) is/are at least substantially round and/or corresponding to a, in particular and/or at least substantially cylindrical, recess (21) in the recess (11). Cartridge piston device according to one of claims 1 to 4, characterized in that the closure element (3) has a sealing element (24), in particular a cone (24), for sealing on a sealing surface (33) of the recess (11). Cartridge piston device according to one of claims 1 to 5, characterized in that the closure element (3) has an auxiliary sealing element (23), in particular a sealing lip (23), for contact with a further sealing surface (47) of the recess (21), preferably wherein the auxiliary sealing element (23) is arranged on the end face (16), on the head side (17) and/or circumferentially around the head side (17), end face (16) and/or the rear side (49). Cartridge piston device according to one of claims 1 to 6, characterized in that the closure element (3) has a securing section (25) for securing the closure element (3) relative to the piston (2), in particular by means of a securing means (26) of the piston (2), particularly preferably a snap ring (26) of the piston (2). Cartridge piston device according to one of claims 1 to 7, characterized in that the closure element (3) and/or the piston (2), in particular in the region of the recess (11) and/or along the insertion direction (18) or extraction direction (19), has a venting possibility (41), in particular having grooves or slots (41). Cartridge piston device according to one of claims 1 to 8, characterized in that the piston (2) has a pre-channel structure (35) on the front side (7) and/or on the rear side (8), preferably wherein the pre-channel structure (35):

- fluidically connects the front side (7) to the recess (11), the channel structure (10) and/or the rear side (8), and/or

- fluidically connects the rear side (8) to the channel structure (10) and/or the recess (11). Cartridge piston device according to claim 9, characterized in that the pre-channel structure (35), in particular on the piston (2) has recesses that are open to the outside and/or to the cartridge (4) and/or are groove-shaped, preferably wherein the recesses are arranged on or within the front side (7) and/or the rear side (8), at least approximately, over the entire surface and/or distributed. Cartridge piston device according to claim 9 or 10, characterized in that the pre-channel structure (35) on the piston (2) has open and/or groove-shaped depressions towards the outside and/or towards the cartridge (4), wherein the depressions within the front side (7) run from the center of the front side (7), in particular from the recess (11) and/or from the countersink (21) to the edge region (36), and in particular open in the edge region, preferably open in an edge depression (37) running around the front side (7) in the edge region, particularly preferably the depressions run radially, preferably spoke-shaped or star-shaped. Cartridge piston device according to one of claims 1 to 11, characterized in that the ratio of the diameter of the head side of the closure element (3) to the diameter of the piston (2), in particular the diameter of the front side (7) of the piston, more preferably the inner diameter (36A) of the edge region (36) of the piston is from 1:2 to 1:10, preferably from 1:3 to 1:7, particularly preferably 1:5, in particular with plus/minus 25%, in particular plus/minus 10%, preferably plus/minus 5%. Cartridge piston device according to one of claims 1 to 12, characterized in that the closure element (3) and/or the piston (2) is made of one or more of: thermoplastic, elastomer, duromer or duroplast, polypropylene (PP), polyethylene (PE) and/or a thermoplastic elastomer (TPE) and/or comprises this/these. Method for venting and closing a cartridge (4) with a cartridge piston device (1), the cartridge piston device (1)

- comprising a piston (2) having a channel structure (10) and a closure element (3) for closing the channel structure (10) by inserting the closure element (3) into a recess (11) of the piston (2) in the region of the front side and by adjusting the closure element (3) into a closed position, or

- designed according to the preamble of claim 1 or according to one of the preceding claims, wherein the method is characterized by the following method steps a. Providing a cartridge, in particular a cartridge (4) filled with cartridge contents, with a piston opening (48), b. Providing the cartridge piston device (1), in particular with the closure element (3) inserted into the recess (11) and/or in an open position, c. Inserting the cartridge piston device (1) into the piston opening (48), with an open position, i.e. Venting the cartridge (4) by inserting the cartridge piston device, wherein the closure element (3) is held fixed by the recess (11) and/or is or can be struck in the pull-out direction (19), and, preferably, e. Closing the cartridge (4) by adjusting the closure element (3) into the closed position by contacting the cartridge contents (5) with the closure element (3) and/or by applying force to the closure element (3), preferably during or after step d. Closure element (3) for use with a piston (2), in particular a piston with an inserted closure element (3) being a cartridge piston device (1) form, wherein the closure element (3) has a head side (17) with an end face (16) and with a back which is opposite the end face (16), and a sealing element. Closure element according to claim 15, characterized in that the closure element has an opening on its end face (16) of the head side (17), which extends from the end face to the back of the head side and is optionally guided through the closure element to the opposite end of the closure element, in particular up to the foot side (62), in particular the opening on the rear side of the closure element opposite the end face having at least three elements (59), each of which has at least two sealing surfaces (60) which extend from the outer circumference of the elements to the opening (61). are designed and through external force on the outer surfaces of the elements, the sealing surfaces of the elements come to lie on one another and thereby close the opening (61) on the side of the closure element facing away from the end face. Piston (2) for insertion into a cartridge, characterized in that it has a front side (7), a rear side (8) facing away from the front side, an outside (9) with a circumferential sealing groove (12) and/or seal (13 ) for circumferential sealing on an inner surface (6) of the cartridge (4), with a recess (11) in the area of the front (7) for inserting a closure element (3) in an insertion direction (18), and optionally a recess (11 ) and the rear side (8) fluidically connecting channel structure (10) for venting the cartridge (4), and the piston (2) in the direction of the front a support surface for the back of the closure element, which is formed essentially perpendicular to the central axis of the piston, which is the end face of the closure element is opposite. Kit comprising at least one cartridge piston device according to one of claims 1 to 13 and a cartridge, in particular a single-chamber or double-chamber cartridge. Use of a cartridge piston device (1) for inserting into a cartridge and closing the cartridge (4) at the back, the cartridge piston device (1) comprising

- a piston (2) having a channel structure (10) and a closure element (3) for closing the channel structure (10) by inserting the closure element (3) into a recess (11) in the piston (2) and by adjusting the closure element (3) into a closed position, or

- designed according to the preamble of claim 1 or according to one of the preceding claims; characterized in that closing the cartridge (4) involves adjusting the closure element (3) into the closed position by contacting one or more of the cartridge contents (5) with the closure element (3) and/or by applying force to the closure element ( 3) is caused.