Beaded edge pad

Abstract

A beaded gasket for sealing a gap between a first component (1) and a second component (40), the beaded gasket (S) comprising: (a) a first gasket layer (20) comprising a retaining element (29; 51); (b) a second gasket layer (30) comprising a complementary retaining element (39; 55); and (c) one or more folded portions (37) connecting the first gasket layer (20) and the second gasket layer (30), wherein the first gasket layer (20), the second gasket layer (30) and the second gasket layer (30) are folded. (0) and the corresponding folding parts (37) are formed as one body, and the lining layers (20, 30) are folded or can be folded onto each other by folding the corresponding folding parts (37) so that they face each other in the axial direction, and (e) wherein the retaining elements (29, 51) and the complementary retaining elements (39, 55) are kept engaged with each other or can be kept engaged with each other based on shape fit and / or friction fit so as to fix the lining layers (20, 30) and prevent them from being separated from each other.

Description

Technical Field

[0001] The present invention relates to a bead gasket for sealing a gap between a first component and a second component. The present invention also relates to a pump, such as a lubricating oil pump, a coolant pump, a vacuum pump or in particular a gear pump, comprising a bead gasket for sealing a fluid outlet of the pump. The pump can be a single-flux pump or a multi-flux pump, in particular a multi-circuit pump. Advantageously, it can be implemented as a cartridge. The pump can be used as a gear pump for supplying a pressure fluid to a gearbox, such as an automatic gearbox or a steering gearbox of a vehicle or a wind turbine. In another application, it can be used as a lubricant pump and / or a coolant pump for supplying a lubricant and / or a coolant (in particular a lubricating oil) to an internal combustion engine, such as a drive motor of a vehicle. It is also conceivable to use it as a combination of a lubricating oil pump and a gear pump, in particular in an embodiment in which the pump is a multi-flux pump. The pump can be used for lubricating and / or cooling an electric motor, which can, for example, form a drive motor or an auxiliary drive motor of a motor vehicle. However, the bead gasket according to the invention can also be used for sealing fluid connections, for example sealing a gap between two parts of a pipe or conduit which are connected to each other, or an inlet or outlet of a hydraulic motor. Background Art

[0002] EP3081741A2 discloses a gear pump with multiple working fluxes. The pump is implemented as a multi-circuit pump and therefore includes independent pressure outlets sealed from each other. The first pressure outlet is sealed by an annular radial liner around the housing of the pump. The outlet liner is arranged in the form of an axial liner in the pressure space obtained by the radial liner, and the outlet liner surrounds the second pressure outlet so as to separate the second pressure outlet from the first pressure space. The pump is constructed as a cylinder and is first introduced into the receiving recess of the receiving device with the outer end side of the pump housing. The pressure fluid delivered by the pump is discharged through the pressure outlet and pressure port of the receiving device axially opposite to the pressure outlet and pressure port. The spring device is supported on the base of the receiving recess and is pressed against the axially opposite outer end face of the pump housing with a spring force, so that the changes in the geometric shape caused by production / assembly tolerances and operation can be compensated in the axial direction.

[0003] US2017 / 0260979A1 discloses a gasket array for a cartridge vane pump, wherein the vane pump has two working fluxes and is implemented as a dual-circuit pump. The gasket array includes radial gaskets and outlet gaskets, the radial gaskets are arranged circumferentially around the circumference of the pump housing and separate the first pressure space of the pump from the suction space, and the outlet gaskets are implemented as axial gaskets and are arranged on the outer end side of the pump insert. The outlet gasket separates the first pressure space of the pump from the second pressure space and seals the shaft channel for the drive shaft of the pump.

[0004] The prior art uses a soft material gasket to seal the corresponding pump outlet. If the gasket is used as an axial gasket, it is difficult to ensure the sealing effect based on the elasticity of the material. The width of the gap sealed by the axial gasket may change, for example, due to thermal changes in the geometry and / or pressure-induced movements of the pump housing or housing parts. Due to component tolerances and / or installation tolerances, the gap width may also vary from installation to installation. The soft material gasket requires a uniform high surface compression on its circumference in order to achieve the necessary sealing. If the surface compression changes between pumps due to changes in temperature and / or pressure or due to different tolerances during pump operation, a continuous and reliable sealing effect can only be ensured with great effort and cost. Stability is also a problem. In the case of pulses, high pressures and large gap widths that need to be bridged, the risk of gap extrusion will increase.

[0005] Metal bead gaskets have been shown to be effective for sealing at high temperatures and cyclic changes in pressure, for example for sealing cylinder heads. DE 42 19 709 A1 discloses such an example.

[0006] Unlike the typical sealing situation where a bead gasket is installed in a fixed, axially tensioned assembly, an outlet gasket for sealing a pressure outlet of, for example, a cartridge pump must not only compensate for the sum of the axial tolerances of the axial assembly of the pump components and the axial tolerances of, for example, the pump chamber, which accumulate under adverse conditions, but also for the thermal expansion of the different parts of the assembly that occurs when the pump is in operation, wherein the sealing surfaces in a typical installation are unconventionally pressed apart by a spring device supported on the base of the chamber, which is usually a pre-tensioned disc spring. Therefore, the outlet gasket must compensate for significantly larger gap width tolerances by means of its axial spring characteristics than a gasket in a fixed tensioned assembly, such as a cylinder head gasket.

[0007] The applicant has developed a bead gasket of the described requirements which is able to meet relatively large variations in compensation gap width. An advantageous bead gasket is disclosed, for example, in German patent application No. 102019132729.6, which relates to arrangements and embodiments of bead gaskets, in particular to hardening one or more gasket rings.

[0008] In order to position two or more lining layers of a bead gasket relative to each other so that the gasket rings of these lining layers are axially flush to a level of precision sufficient for the application, the lining layers are fixed to each other when the bead gasket is manufactured. They can be fixed by rivets, for example in the case of cylinder head gaskets. A prerequisite for the rivet solution is that the structural constraints allow the rivet to be positioned outside the area of ​​the gasket ring so that the rivet head axially raised above the gasket ring does not abut prematurely when the bead gasket is installed and tensioned. It is also possible to connect the lining layers by providing one lining layer with one or more hollow rivet-shaped notches and another lining layer with one or more holes in a stamping and deep drawing process, and then by inserting the notches into the corresponding holes and riveting them. This rivet solution has the additional disadvantage that there is a risk of material fracture in the area of ​​the notch due to the high degree of deformation of the spring steel used in most cases, and the spring steel can only be plastically deformed to a limited extent. It is also known to provide one of the backing layers with sheet metal tabs which are folded around the circumferential edge of the other backing layer when the backing layers are connected. The disadvantage of this folded connection is that the folded sheet metal tab requires a relatively high degree of deformation and therefore requires significant plastic deformation, which therefore leads to the risk of fracture of the corresponding sheet metal tab. In addition, since the folded sheet metal tab exceeds the thickness of one of the backing layers in the connection area, this creates an overall axial height that exceeds the backing layer connected in this way. It is also known to connect the backing layers by welding. A major disadvantage of welding is that the welding process makes it more difficult to meet the requirements for technical cleanliness of beaded edge gaskets due to the inevitable generation of molten spatter and metal oxides. In order to use beaded edge gaskets in high-pressure pumps of automatic transmissions, for example, which is also particularly targeted by the present invention, the residual contamination problems associated with the welding process are equivalent to non-conforming standards. The mentioned joining process is associated with considerable effort and expense.

[0009] In order to avoid these problems, EP1389701A2 proposes to provide a gasket layer of a flat gasket with a retaining element and another gasket layer of a flat gasket with a complementary retaining element, in each case, the retaining elements are engaged with each other front and back in a retaining engagement manner. The document also mentions the option of using the multi-layer flat gasket to seal the engine block and cylinder head. But there is no description of the bead gasket. The gasket layer of the multi-layer flat gasket joined with a plurality of retaining elements and complementary retaining elements (in each case, retaining engagement with each other) can also be obtained from DE19822772A1, which does not mention any specific application and does not refer to any embodiment of the flat gasket as a bead gasket. The multi-layer flat gasket of the prior art consists of a gasket layer produced separately, which is connected by means of a plurality of pairs of retaining elements and complementary retaining elements, and the retaining elements are distributedly arranged on the surface of the corresponding flat gasket. In order to connect, the gasket layers must be separated and positioned and maintained relative to each other. Since a large number of retaining elements and complementary retaining elements must be moved to retain engagement with corresponding pairs, the engagement itself is also laborious and expensive. Summary of the invention

[0010] The object of the present invention is to provide an inexpensive gasket for axial sealing contacts which is able to effectively and reliably (over a longer period of time) compensate for component tolerances and / or mounting tolerances and / or thermally induced changes in geometry and / or pressure-induced movements of the components at the mounting point of the gasket, while maintaining the necessary sealing effect.

[0011] One aspect is ease of handling. The multi-layer bead liner should be able to be easily and safely stored in a magazine, transported, separated for assembly and automatically assembled in a process-safe manner in an assembly system.

[0012] Another aspect is technical cleanliness. When connecting two or more gasket layers, as little dirt as possible and advantageously no dirt should be introduced into the bead gasket.

[0013] Another object of the invention is to provide a pump which is suitable for being arranged in a receiving recess of a receiving device and, for this purpose, comprises a housing end wall which comprises one or more pressure outlets for discharging pressurized fluid from a delivery chamber of the pump. The seal on the one or more pressure outlets in such a pump should be improved cost-effectively with regard to component tolerances and / or installation tolerances of the receiving device and the pump and / or thermally induced geometric changes and / or pressure-induced movements of the housing structure of the pump.

[0014] The invention proposes a multi-layer bead liner. The bead liner comprises: a first liner layer, which comprises a retaining element; a second liner layer, which comprises a complementary retaining element; and one or more folded parts, which connect the first liner layer and the second liner layer. The bead liner may comprise one or more further liner layers and may, for example, have three or four layers. However, in particular, the first liner layer and the second liner layer may form the bead liner alone as a double-layer bead liner.

[0015] The first backing layer, the second backing layer and the corresponding folded portion are formed as one piece, for example from a spring steel sheet. The beaded edge backing can be provided in a folded state or in an unfolded state. In the folded or only partially folded state, the backing layers face each other in the axial direction. In the folded state, one of them is located on top of the other, which also includes the case where one is located on top of the other through an intermediate layer. However, preferably, in the folded state, one of them is directly located on top of the other.

[0016] The retaining element and the complementary retaining element are or can be retained in engagement with each other based on a form fit and / or a friction fit. In the retained engagement, they secure the cushioning layers against separation from each other, which separation could occur in the unsecured state, for example due to deformations of the corresponding folded parts (which are not only plastic deformations but also elastic deformations to a certain extent, albeit to a small extent) and / or minor molding defects in the typically thin cushioning layers.

[0017] In a first advantageous embodiment, the beaded liner is managed by a retaining engagement, i.e. in such an embodiment, the liner layers fixed or to be fixed relative to each other comprise only one retaining element and one complementary retaining element, respectively. In a second embodiment, the first liner layer comprises a further retaining element and the second liner layer comprises a further complementary retaining element, which further retaining element and the further complementary retaining element are engaged behind each other in another retaining engagement or can be moved into said another retaining engagement in order to fix the liner layers and prevent them from separating from each other. The possibility is also not excluded that the first liner layer comprises one or more other retaining elements and the second liner layer comprises one or more other complementary retaining elements, which are in or can be moved into retaining engagement in respective pairs. However, in an advantageous embodiment, the beaded liner is managed with only one or at most two pairs of retaining elements and complementary retaining elements.

[0018] By making two or more cushioning layers in one piece and folding and fixing them in a retained engagement, a multilayer beaded gasket can be obtained in a small number of manufacturing steps. Unlike the prior art, the cushioning layers do not have to be produced individually, stored in a box, separated again, positioned one on top of the other or on top of the other and held in position relative to each other when connected. The folding ensures and advantageously even improves the precision with which the cushioning layers are positioned relative to each other. Compared to a beaded gasket made of separately manufactured cushioning layers, the number of retaining elements and complementary retaining elements that are retained in engagement can be reduced, since the cushioning layers no longer need to be positioned relative to each other by means of a plurality of retaining elements and complementary retaining elements. Due to the combination with the folding, the function of one or several retaining elements and complementary retaining elements can be reduced to ensuring that the cushioning layers do not separate from each other.

[0019] The retaining element and the complementary retaining element can be molded and arranged on the corresponding lining layer so that the retaining engagement is at least substantially based on a friction fit or at least involves a friction fit. The retaining engagement can be, for example, a plug engagement. In such an embodiment, one of the retaining element and the complementary retaining element can be provided in the form of a channel in the lining layer in question, such as a circular hole, while the other is formed as a cam-like or pin-like axial protrusion on the other lining layer. In the retaining engagement, the axial protrusion is located in the channel in a friction fit, wherein the protrusion can advantageously be sufficiently flat in the axial direction so that it does not protrude beyond the channel on the other side in the retaining engagement.

[0020] In a further advantageous embodiment, however, the retaining element and the complementary retaining element are moulded and arranged on the respective backing layer so that the retaining engagement is at least substantially based on a positive fit. The retaining element and the complementary retaining element can in particular engage behind each other in the retaining engagement with respect to the axial direction and be pressed against each other in the axial direction with a tensioning force based on elastic deformation. The tensioning force can be based on an elastic deformation of one or more folded parts and / or on an elastic deformation of the retaining element and / or on an elastic deformation of the complementary retaining element. When the retaining engagement is established, the retaining element and the complementary retaining element can in principle also be deformed plastically, but preferably only or at least substantially elastically, and be pressed against each other in the axial direction with an elastic tension so as to tension the backing layers axially relative to each other with said elastic tension.

[0021] The retaining element and / or the complementary retaining element (each) can be, for example, a latching element, and the retaining engagement can be a latching engagement accordingly. In this embodiment, the retaining element and the complementary retaining element can be molded so that they first slide away from each other when establishing the retaining engagement, wherein the retaining element and / or the complementary retaining element are elastically deformed, and the retaining element and / or the complementary retaining element deformed in this way are released and snapped into the retaining engagement in the last part of the relative movement. More advantageously, when establishing the retaining engagement, the retaining element and / or the complementary retaining element are elastically deformed by a tool, and are conveniently maintained in their elastically deformed state by the same tool until the retaining element has passed after the complementary retaining element when observed from the first lining layer. Once the retaining element and the complementary retaining element have reached this relative position, the corresponding element that has been elastically deformed can be released at this time, so that it is pressed against another element with a tensioning force based on the elastic deformation. In this embodiment, when the tensioning force is generated only by the elastic deformation of the retaining element and / or the complementary retaining element, the lining layer is maintained to have no axial gap in the region of retaining engagement.

[0022] The retaining engagement may be non-releasable. However, more preferably, the retaining engagement may be non-destructively releasable.

[0023] In a retaining engagement, the retaining element can engage behind the peripheral edge of the second cushioning layer, or the complementary retaining element can engage behind the peripheral edge of the first cushioning layer, when viewed from an axial plane perspective. The axial plane extends in the axial direction and is therefore at least substantially perpendicular to the cushioning layers. The peripheral edge is free in the sense that the respective cushioning layer does not extend beyond the free peripheral edge when viewed from a planar perspective. Since the free peripheral edge is automatically generated when manufacturing the beaded cushion, for example when stamping the cushioning layer from a metal sheet, a retaining element or complementary retaining element extending up to and including the free peripheral edge of the cushioning layer can be manufactured very easily. The retaining element or complementary retaining element does not have to be specially formed, but inevitably occurs as a by-product during production.

[0024] The retaining element and / or the complementary retaining element (each) can protrude freely from the root end. Advantageously, the freely protruding retaining element and / or the freely protruding complementary retaining element can be elastically flexible and thus (respectively) form a spring tongue. A particularly preferred combination is that one of the two elements (e.g. the retaining element) is designed as a spring tongue and the other element (e.g. the complementary retaining element) is designed so that the free peripheral edge and the edge section directly abut inwards in a top view.

[0025] When the retaining element and / or the complementary retaining element is implemented as a spring tongue, the element advantageously presents a cross section whose size increases towards the root end when viewed from the free end and preferably widens on the backing layer in an axial planar perspective. Preferably, its size increases continuously. Advantageously, the spring tongue has its largest cross section at the root end, for example its widest cross section in a planar perspective. When implemented as a protruding spring tongue, the retaining element and / or the complementary retaining element may protrude with a transition radius in a planar perspective at the root end.

[0026] The retaining element and / or the complementary retaining element (each) can be a spring tongue, in particular a spring tongue as described above. In a simple embodiment, the spring tongue that does not bear the load extends continuously from its root end to its free end in the lining layer forming the spring tongue. Preferably, if the lining layer is planar in the immediate vicinity of the spring tongue, the spring tongue is also planar accordingly. In a refinement, the free end of the spring tongue that does not bear the load extends from the lining layer to which it belongs relative to the axial direction. The spring tongue can protrude suddenly from its immediate vicinity via a sharp angled bend or via a gentle bend, so that in a side view, its free end protrudes beyond the immediate vicinity of the lining layer forming the spring tongue. As already mentioned, the immediate vicinity can be particularly planar. In a further refinement, before establishing the retaining engagement, when the lining layers face each other axially and do not bear the load, the free end of the spring tongue extends out of the lining layer forming the spring tongue in a direction away from another lining layer. In order to establish the retaining engagement, the pre-molded elastic tongue must be elastically deformed to a greater extent than the elastic tongue in the simple embodiment described above, thereby increasing the tensioning force of the elastic tongue acting in the axial direction during the retaining engagement. Considering that the lining layer is typically of small thickness, this is advantageous in order to ensure a secure retaining engagement.

[0027] The retaining element and / or the complementary retaining element (each) can be curved circularly in the axial direction and curved back again or advantageously crimped in order to keep the thickness of the bead liner small in the region of the retaining engagement. The curved or crimped element extends from the plane of its associated liner layer into the plane of the other liner layer. When implemented as a crimped element, it can be particularly shaped as a step with a shoulder which is inclined axially or obliquely relative to the axial direction. Thus, the local total thickness of the retaining engagement portion can be at least substantially limited to the sum of the thicknesses of the liner layer immediately adjacent to the retaining engagement portion.

[0028] In an advantageous first embodiment, the retaining element and the complementary retaining element act on each other in the retaining engagement only in the axial direction. In a second embodiment, they may comprise abutment points which face each other in the retaining engagement transversely to the axial direction and which limit the mobility of the gasket layer transversely to the axial direction by the abutment contact between the abutment points. However, since the gasket layers are positioned relative to each other transversely to the axial direction by one or more folded portions, it is possible to dispense with additionally fixing them in the retaining engagement transversely to the axial direction, in particular since transverse abutments also always present a risk of wear and therefore of ingress of contamination in the event of relative movements, such as may occur between the gasket layers during operation.

[0029] The one or more folds define a fold axis of the bead liner. In an axial plan view of the unfolded bead liner, the fold axis extends transversely relative to the axial direction in the one or more folds. It may extend through the one or more folds. However, in most embodiments, it will extend to the fold with a certain axial offset before folding.

[0030] In an advantageous embodiment, one or more fold portions (each) are significantly narrower than the bead liner when measured along the fold axis in plan view. In an advantageous embodiment, the maximum width of the bead liner measured parallel to the fold axis is at least three times or at least five times the width of the corresponding fold portion. The maximum width of the bead liner mentioned here only refers to the width measured parallel to the fold axis.

[0031] The first backing layer and the second backing layer may be connected to each other by only one folded portion. However, in a refinement, the beaded backing layer comprises a first folded portion and a second folded portion, which extend at a distance from each other in an axial plan view. Thus, in a plan view of the beaded backing layer which has not yet been folded, i.e. in a flat projection of the beaded backing layer, material-free cavities are formed between the folded portions along the fold axis. In a preferred embodiment, the first backing layer and the second backing layer are connected to each other by exactly two folded portions, which folded portions are relatively narrow when the fold axis is measured in a plan view.

[0032] In an axial plan view of the unfolded bead gasket, the first backing layer and the second backing layer may protrude in the shape of wings facing away from the one or more folded portions.

[0033] In order to accurately position the lining layers relative to each other, it is advantageous if, in the unfolded state of the bead lining, the corresponding folding portions are pre-moulded along the folding axis, i.e., pre-moulded folding portions are provided, for example locally bulged or raised along the folding axis, so as to predefine the folding axis and facilitate folding.

[0034] In order to avoid problems during transport, storage, separation and finally automatic assembly of the bead liner, it is advantageous if, once the retaining engagement has been established, the lining layers are brought close to each other on the peripheral edges to prevent the bead liner from snagging. To this end, it is advantageous if the first lining layer and / or the second lining layer (preferably both lining layers) are respectively bent concavely upwards relative to the other lining layer to their peripheral edges. This means that when the lining layers are axially facing each other and before the retaining engagement is formed, the respective lining layer is concave relative to the other of the lining layers up to its peripheral edge in an axial plane parallel to the folding axis and perpendicular to the lining layers, without forces acting thereon, so that the end-facing surfaces of the lining layers close to the peripheral edge converge towards the peripheral edge at an acute angle in these axially extending planes and enter into surface contact or at least limited linear contact near the peripheral edge only due to the action of axial forces, which axial forces can be generated in particular in the retaining engagement between the retaining element and the complementary retaining element. Thus, any separation and the associated gap formed on the outer circumference of the bead liner can be offset. This concave pre-molding means that, due to the axially acting forces in the retaining engagement, the backing layers are elastically deformed to a lesser extent on the outer circumferential edge and in the region close to the edge, as viewed over their entire surface, and thus bear against each other on the outer circumferential edge.

[0035] In order to obtain the concavity, the first cushion layer and / or the second cushion layer can be bent with a large radius of curvature, so that in each case there is a flat circular protrusion relative to the other cushion layer. In an advantageous embodiment, the first cushion layer and / or the second cushion layer is bent at an acute angle and, when not under load, is inclined obliquely from the bend to both sides in a roof shape. In an axial plane view on the cushion layer pre-molded in this way, the curved portion can advantageously extend obliquely at an angle of 90°±30° or 90°±20°. The smaller the angle deviates from 90°, the more advantageous the arrangement. Preferably, the curved portion extends orthogonally relative to the folding axis. On the contrary, it is advantageous if the curved portion extends only along one or more cushion rings of the corresponding cushion layer without passing through the cushion ring. In an axial plane parallel to the folding axis and perpendicular to the cushion layer, the cushion layer forms a flat triangle or a flat rhombus before establishing a retaining engagement. In a plan view, the curved portion can particularly extend through the central area of ​​the curved cushion layer. In principle, the corresponding cushion layer can also be bent multiple times. Advantageously, however, the respective cushioning layer exhibits only one bend.

[0036] In another improvement which is advantageously combined with the above-mentioned improvement but can also be implemented in this way, the first lining layer and / or the second lining layer are bent in a folding plane in the absence of a force acting on them, which folding plane is orthogonal to the folding axis and extends through the retaining engagement portion, in each case protruding from the folding axis towards the retaining engagement portion and away from the other of the lining layers. This protrusion also refers to the state in which the lining layers face each other axially but have not yet established a retaining engagement. This convex curvature increases the tensioning force acting in the axial direction when retaining engagement and offsets any axial clearance when retaining engagement. This is advantageous both for the processing as already described in conjunction with the recess and for its use in preferred applications, for example as an outlet liner of a pump, so as to be able to better compensate for axial component tolerances and / or assembly tolerances and / or changes in pressure and / or temperature.

[0037] In particular, the bead liner can be a metal bead liner, thus making it possible to provide a liner that is inexpensive, reliable and durable (due to no gap extrusion) and promotes technical cleaning (no wear of elastomer particles) compared to elastomeric liner or elastomeric composite liner. The liner layer is preferably a metal sheet structure. The liner layer is preferably made of spring steel sheet. The liner layer, including the retaining element and the complementary retaining element, can be formed continuously from a metal sheet, in particular a spring steel sheet, by one or more folded parts, preferably by stamping and deep drawing. Thus, in a first step, channels for fluids and cavities can be produced by stamping, for example for the manufacture of retaining elements or, depending on the application, a plurality of retaining elements, one or more washers and the corresponding washers blanks (i.e. the unfolded bead liner) can be formed by deep drawing, and then a larger metal sheet can be stamped out separately.

[0038] In particular, the bead gasket may be an uncoated metal bead gasket. However, the possibility is not excluded that the bead gasket is a metal bead gasket and the first gasket layer and / or the second gasket layer are coated or covered with a flexible gasket material to improve the micro-sealing effect, such as an elastomer or thermoplastic elastomer (TPE). An uncoated metal bead gasket is more preferred, because elastomer coatings increase the risk of wear and / or separation and thus contamination.

[0039] In an advantageous embodiment, the first gasket layer comprises a first gasket ring and the second gasket layer comprises a second gasket ring. In an axial plan view, the first gasket ring surrounds a first internal region through which a fluid can flow and which comprises a gasket end surface for axial contact with one of the components defining the gap to be sealed. In a plan view, the second gasket ring surrounds a second internal region through which a fluid can flow and which comprises a gasket end surface for axial contact with another of the components defining the gap. As observed in the plan view, the first internal region and the second internal region at least partially and preferably completely overlap each other. At least one gasket ring (gasket loop) is a bead loop. In the case where the gasket ring is a bead loop, the gasket end surface is a bead end surface, wherein the first gasket ring may be a first bead loop and / or the second gasket ring may be a second bead loop. Preferably, the first gasket ring is a first bead loop and the second gasket ring is a second bead loop. In principle, however, it is conceivable that one of the two backing rings is, for example, a planar backing ring which is coated with an elastic backing material, for example on the outer side facing away from the other backing ring.

[0040] Due to the linear compression of the corresponding gasket ring, the critical minimum surface compression can be maintained better than when using soft material gaskets even when the gap width changes relatively significantly. The bead gasket according to the invention can advantageously compensate for changes in gap width of more than 0.1 mm, in some applications 0.2 mm or even more.

[0041] The first gasket layer comprises a channel for a fluid located in the first inner region. In an axial plan view, the first gasket ring surrounds the channel located in the first inner region. It is the smallest gasket ring surrounding the channel in the first inner region. This means that the channel cannot be surrounded by any smaller gasket ring. In an axial plan view, the first gasket ring also preferably does not surround any other sealing stays of the bead gasket, such as another gasket ring. The first gasket layer preferably comprises a plurality of channels arranged side by side with each other in the first inner region, and the first gasket ring surrounds these channels as the smallest gasket ring. If the first gasket ring is implemented as a first gasket ring, it is preferably a half gasket, but can also be a full gasket instead.

[0042] The second gasket layer also includes a channel for the fluid located in the second inner region. In the axial plan view, the second gasket ring surrounds the channel located in the second inner region and is the smallest gasket ring surrounding the channel in the second inner region. This means that the channel cannot be surrounded by any smaller gasket ring. In the axial plan view, the second gasket ring also preferably does not surround any other sealing stays of the beaded gasket, such as another gasket ring. The second gasket layer preferably includes a plurality of channels arranged side by side with each other in the second inner region, and the second gasket ring surrounds these channels as the smallest gasket ring. If the second gasket ring is implemented as a second gasket ring, it is preferably a half gasket, but it can also be a full gasket instead. If the first gasket ring and the second gasket ring are each flanged loops, the first flanged loop and the second flanged loop are preferably of the same type.

[0043] The axial direction is the main flow direction of the fluid through the respective channels of the first and second lining layers.

[0044] In plan view, the first backing ring may completely surround the first inner region over 360° and advantageously surround the one or more channels without gaps and / or interruptions. In such an embodiment, the first inner region is fluidically separated from the radially outer vicinity of the backing ring in sealing contact when installed. However, in principle, the possibility is not excluded that the first backing ring allows a flow in a radial direction outwards from or into the first inner region, without locally interrupting it at one point on its circumference or, where applicable, also at a plurality of points. The same applies analogously to the second backing ring.

[0045] The first backing layer may include a first stiffening structure extending in plan view from the first backing ring into the first inner region, preferably traversing the first inner region, and thereby stiffening the first backing ring. Alternatively or preferably, in addition to the first backing layer, the second backing layer may include a second stiffening structure extending in plan view from the second backing ring into the second inner region, preferably traversing the second inner region, and thereby stiffening the second backing ring.

[0046] If the axial width of the gap to be sealed decreases due to changes in operating conditions or tolerances from mounting component to mounting component, the corresponding hardening structure makes it more difficult to elastically deform the bead gasket in the corresponding internal area. The hardening in the first internal area and / or the second internal area improves the forced displacement characteristics of the bead gasket, so that the bead gasket according to the present invention can compensate for larger changes in the axial width of the joint to be sealed. Compared with a bead gasket of conventional design without a hardening structure (reference gasket), the surface compression and / or linear compression in the sealing contact is increased. The bead gasket according to the present invention offsets the reduction in the joint width within the expected range of joint width variation by a return spring force greater than that of the reference gasket. It can advantageously be installed with a higher axial bias force than the reference gasket.

[0047] When the corresponding gasket ring is embodied as a half-gasket, the stiffening structure can reduce the tendency of the gasket ring to fold or tilt, so that the sealing contact can be ensured more reliably.

[0048] If a first hardening structure is provided, the first hardening structure and the first backing ring are advantageously fixedly connected to one another, particularly advantageously formed in one piece, and particularly cannot be separated from one another without being destroyed. If a second hardening structure is provided, the second hardening structure and the second backing ring are advantageously fixedly connected to one another, particularly advantageously formed in one piece, and particularly cannot be separated from one another without being destroyed.

[0049] The phrase "formed in one piece" is to be understood to mean formed in such a way that no joining is required. If a corresponding backing ring and its stiffening structure are provided, they are preferably formed from one blank, advantageously by moulding said blank.

[0050] In a simple embodiment, the first gasket layer comprises only the first gasket ring and therefore presents only the first inner region. In a further improvement, the first gasket layer comprises a (further) third gasket ring. The third gasket ring can in particular be a washer ring and, for reasons of association, is referred to as a third gasket ring in such an embodiment. In an axial plane view, the third gasket ring surrounds a third inner region positioned side by side with the first inner region and comprises a gasket end face surface, preferably a gasket end face surface, for axial contact with one of the components. The first gasket layer may comprise a third gasket ring side by side with the first gasket ring in an axial plane view, preferably spaced a certain distance from the first gasket ring, thereby being separated from the first gasket ring. A fluid channel is also provided in the third inner region. The third gasket ring can also be the smallest gasket ring surrounding the channel of the third inner region. With regard to hardening the third gasket ring by an optional third hardening structure, the statements made about hardening the first gasket ring can be applied similarly. If the third gasket ring is implemented as a gasket ring, it is preferably a half gasket, but can also be a full gasket instead.

[0051] The bead gasket may be implemented in a conventional manner with respect to the third gasket ring, or, as in a preferred embodiment, may include a third stiffening structure extending from the third gasket ring into a third interior region to stiffen the third gasket ring.

[0052] The second gasket layer may include a fourth gasket ring, preferably a gasket ring. In an axial view, the fourth gasket ring may surround a fourth inner region including one or more fluid channels and include a gasket end face surface, preferably a gasket end face surface, for sealing contact with a component or another gasket ring. The third gasket ring and the fourth gasket ring may be arranged relative to each other so that the third inner region and the fourth inner region overlap each other in an axial plane view. With regard to hardening the fourth gasket loop by an optional fourth hardening structure, the statements made with regard to hardening the first gasket ring may be applied similarly. If the fourth gasket ring is implemented as a gasket ring, it may be a full gasket or a half gasket. In an advantageous embodiment, the third gasket ring and the fourth gasket ring are arranged to be of the same type.

[0053] When the bead liner is ready to be assembled, one of these lining layers is axially located on top of the other. An intermediate layer or multiple intermediate layers may be provided between the first lining layer and the second lining layer. However, in a preferred embodiment, one of the first lining layer and the second lining layer is directly located on top of the other.

[0054] Each of the first backing ring and any further backing rings comprises a backing end face surface, preferably a washer end face surface, for axial contact with a stay of the respective component or an optional intermediate backing layer of the backing. Here, in conjunction with the hardening structure, the respective hardening structure extends from the respective backing ring into its inner region in an axial plane view, which means that when the beaded backing gasket is mounted, the hardening structure protrudes radially inwardly beyond the stay of the respective component. Thus, the hardening structure impedes the flow of the fluid in the axial direction, i.e. it forms a flow resistance.

[0055] The corresponding stiffening structure can protrude slightly from the backing ring into the inner region, which stiffening structure is provided for stiffening. For example, it can slightly elongate the backing ring radially inwards so that the corresponding backing ring protrudes slightly circumferentially and annularly inwards beyond the component stay where it will be placed.

[0056] In a preferred embodiment, the respective hardening structure traverses the inner region of the backing ring to which it is provided for hardening. In an advantageous embodiment, the hardening structure traverses the central region of the respective inner region. In an axial plan view, the respective hardening structure can be, for example, a connecting strut that traverses the respective inner region. In an improved embodiment, the respective hardening structure can include a plurality of connecting struts. The plurality of connecting struts can be, for example, arranged in a star shape in a plan view. In other embodiments, the respective hardening structure is a grid-like, mesh-like or sieve-like structure.

[0057] The corresponding rigidifying structure can be disc-shaped (ie flat) or channel-shaped (ie curved).

[0058] In principle, it is sufficient to provide a continuous fluid channel in the inner region of the respective gasket ring. However, in a preferred embodiment, a plurality of mutually separated channels are arranged in the respective inner region, which channels together form a cross section of the respective gasket ring or the respective inner region, through which the fluid can flow. The respective hardening structure can then, for example, occupy more than 30% or more preferably a large part of the inner region surrounded by the respective gasket ring, and the one or preferably more channels of the respective gasket ring can be provided. The optional first hardening structure and / or the optional second hardening structure and / or the optional third hardening structure and / or the optional fourth hardening structure can in particular be perforated multiple times, i.e. can comprise a plurality of channels for the fluid which are arranged side by side with each other in a plan view, which together form a cross section through which the fluid surrounded by the respective gasket ring can flow, i.e. a flow cross section. The cross-sectional area of ​​the inner region surrounded by the respective gasket ring measured in an axial view is advantageously at least five times or at least ten times larger than the corresponding individual channels of the plurality of channels. The channel can in particular be a channel hole in the shape of an arc of a circle, for example a circle.

[0059] In applications where the bead gasket is used to seal the outlet of a lubricating oil pump, a corresponding hardened structure can advantageously be used as a throttle valve. The throttling effect of the corresponding hardened structure is advantageous in the cold initial state of the pump in order to reduce pressure peaks caused by the increased viscosity of the fluid in the cold state. Such pressure peaks could, for example, damage a filter arranged downstream of the pump.

[0060] Preferably, the pump can be implemented as a vane pump. The sub-vane regions of the blades can be connected to the high-pressure side of the pump so that the fluid on the high-pressure side can be applied to the lower side of the blades. In a vane pump with sub-vane pressure supply, the first hardening structure and / or the second hardening structure (if provided) can be used as a cold start aid. Additionally or alternatively, the third hardening structure (if provided) and / or the fourth hardening structure (if provided) can be used as a cold start aid. In particular, in a cold initial state, for example when the pump is cold started, the throttling effect of the corresponding hardening structure makes it difficult for the conveyed fluid (especially oil) to flow out of the pump. Preferably, the sub-vane region is connected to the high-pressure side of the pump upstream of the bead liner. In this embodiment, the corresponding hardening structure produces an enhanced throttling effect due to the increased viscosity of the fluid in the cold state, and therefore the pressure is supplied particularly quickly to the sub-vane region when the pump is cold started, so that during the cold start, even at a low rotational speed of the conveying member, the fluid presses the blade outward against the stroke contour around the rotor. The corresponding stiffening structure can be designed such that the delivered fluid is preferably available for the secondary blade pressure source in the cold state and the secondary blade region is therefore preferably supplied with fluid in order to press the blade outwards against the stroke contour.

[0061] In addition or in other applications, a corresponding stiffening structure can be used, for example, as a filter or screen. It is also conceivable that a corresponding stiffening structure is used to homogenize a fluid flow.

[0062] The invention relates not only to the bead gasket itself, but also to the preferred application for sealing one or more pump outlets. The invention also relates to a pump for applying a pressure fluid to a unit or for supplying a pressure fluid to a unit. For example, this can be a gear pump for supplying a gearbox with hydraulic fluid, a lubricant pump and / or a coolant pump for supplying a lubricant and / or a coolant (e.g. lubricating oil) to a drive motor, such as an internal combustion engine or an electric motor.

[0063] The pump comprises a pump housing having a housing peripheral wall and a housing end wall. The housing peripheral wall surrounds a delivery chamber of the pump. The housing end wall has an outer housing end face axially facing away from the delivery chamber. The housing end wall can advantageously define the delivery chamber at one of its end sides, but it does not have to be a chamber wall, but can instead be moved back relative to the delivery chamber. The pump housing comprises an inlet and an outlet for the fluid. The outlet is exposed on the outer housing end face of the housing end wall. The pump also comprises a delivery member that can move within the delivery chamber so as to deliver the fluid from the low-pressure side of the pump including the inlet to the high-pressure side of the pump, where the fluid is delivered through the outlet.

[0064] According to the present invention, the pump comprises a bead liner, which comprises a first liner layer and a second liner layer axially one above the other. Preferably, the liner layers are axially against each other. The bead liner is used as an outlet liner. The first liner layer comprises a first liner ring and the second liner layer comprises a second liner ring. In the axial plan view of the pump, the first liner ring surrounds a first internal area through which a fluid can flow. It comprises a liner end face surface for axial contact with a sealing stay. In the axial plan view, the second liner ring surrounds a second internal area through which a fluid can flow and comprises a liner end face surface for axial contact with another sealing stay. The first internal area and the second internal area overlap each other at least partially and preferably completely in the plan view. At least one liner ring is a gasket ring, so the first liner ring is a first gasket ring and / or the second liner ring is a second gasket ring. The corresponding gasket end face surface is a gasket end face surface. One of the liner rings faces the outer end face of the housing axially and surrounds the outlet in the plan view so as to seal the outlet. When the pump is installed, the end face of the gasket ring is in axial sealing contact with the sealing stay of the housing outer end face of the pump housing. The other gasket ring includes a gasket end face surface, which is axially away from the housing outer end face for axial sealing contact.

[0065] If the bead liner comprises a first stiffening structure and / or a second stiffening structure, the respective stiffening structure overlaps the outlet in plan view, ie protrudes into the free flow cross section of the outlet.

[0066] If the bead liner is used as an outlet liner, the pump is particularly suitable, especially due to the bead liner according to the invention, for applications in which the pump housing at least partially protrudes into the receiving recess of the receiving device, such as a typical gear pump. In such an application, firstly, the pump and the bead liner protrude axially into the receiving recess so that the bead liner seals the pump outlet relative to the base of the receiving recess. An axial gap is formed between the outer end face of the pump housing on which the bead liner is arranged and the base of the axially opposite recess.

[0067] The bead gasket can be arranged in an indirect force line to the spring device. For example, a spring device can be provided so that the housing end wall is pressed axially against the housing peripheral wall by spring force when the pump is installed, if the two housing walls are arranged in a loosely stacked axial arrangement, such as is common in barrel pumps. The spring device advantageously absorbs a larger part of the axial force acting via the axial gap than the bead gasket. In the axial sealing contact, the bead gasket arranged in the indirect force line only needs to absorb the axial force required for a safe seal and can therefore be optimized for its actual function, i.e. its sealing effect. The bead gasket can alternatively be arranged on a straight line of force. In such an embodiment, it can form a spring device so as to axially tension the pump during the tightening of the pump. If a spring device is provided, the spring device can be arranged at the mounting point, or preferably can be a preassembled component of the pump.

[0068] The pump may be, for example, a linear stroke pump or more preferably a rotary pump. As a rotary pump, it may be an external shaft pump, such as an externally driven gear pump. Alternatively, it may be an internal shaft pump, such as an internal gear pump or a reciprocating piston valve pump or preferably a vane pump. The delivery member may be a gear that can rotate around the axis of rotation in the delivery chamber, or may include a rotor and a vane or a slide valve that can rotate around the axis of rotation in the delivery chamber so as to deliver the fluid from the low pressure side of the pump to the high pressure side of the pump and through the outlet of the pump. The delivery member may advantageously be used to form a delivery unit that periodically increases and decreases in size as the rotor rotates so as to deliver the fluid from the low pressure side of the pump to the high pressure side of the pump.

[0069] In an advantageous embodiment, the bead liner of the pump is a bead liner such as is also disclosed herein itself. The liner layers are then connected to each other by one or more folded portions and are fixed by at least one, preferably exactly one, retaining engagement to prevent separation from each other. However, the first liner layer and the second liner layer can in principle also be produced separately, and the first liner layer can include a plurality of retaining elements distributed around the first liner ring, and the second liner layer can include a plurality of complementary retaining elements distributed around the second liner ring, so as to position the liner layers one above the other with a plurality of retaining engagement structures and hold them in place relative to each other. In such an embodiment, there is no folding step. The multilayer bead liner is also advantageous for use as an outlet liner of a pump, simply because it has a larger spring displacement, regardless of whether the two or more liner layers are produced as a whole and folded over one another, or whether the two or more liner layers are fixed to each other or positioned relative to each other by one or more retaining engagement structures of the type disclosed herein.

[0070] For the bead gasket itself and as an outlet gasket for a pump, the characteristics of at least one gasket layer relative to each other in each case are already advantageous, such as the concave and / or convex pre-molding that is optionally implemented, while not bearing loads, that is, in each case, the curvature of at least one gasket layer relative to each other is in the form of a rounded protrusion or by a flat roof. In such an embodiment, the gasket layers arranged one above the other, preferably one above the other, can also be tensioned against each other in a circumferential area around the first gasket layer and the second gasket layer, and thus uniformly move into sealing surface contact on the circumference and remain in said surface contact. This also applies to modifications such as such that the first gasket layer and the second gasket layer are produced separately and are held together by a plurality of retaining elements and complementary retaining elements of the above-mentioned type, which are distributed around the gasket ring. On the contrary, even without a retaining joint structure of the above-mentioned type, for example in combination with a different joint connection instead of a retaining joint, such as a folding connection or a riveted connection, it is also advantageous to produce the first gasket layer and the second gasket layer together with one or more folding parts and fold them into a multilayer bead gasket.

[0071] Another feature which is entirely advantageous in itself is the hardening of one or more gasket rings in the interior region of the single-layer or multi-layer bead liner by means of the hardening structure(s).

[0072] The features described herein in combination with folding or foldability or retaining engagement can advantageously be implemented in any beaded edge gasket for sealing a gap between a first component and a second component, the beaded edge gasket comprising a first lining layer with a retaining element and a second lining layer with a complementary retaining element, wherein the lining layers are joined to each other by a joining connection structure. The joining connection structure can in particular be a retaining engagement structure based on a form fit and / or a friction fit of the type disclosed herein, but in principle can also be a different type of joining connection, such as a rivet connection or a folding connection between the retaining element and the complementary retaining element. This type of multilayer beaded edge gasket can implement any of the features disclosed herein, even without the feature of folding / foldability and / or without the feature of retaining engagement based on a form fit and / or a friction fit. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] An exemplary embodiment of the present invention is explained below based on the drawings. The features disclosed by this exemplary embodiment, each individually and in any combination of features, advantageously expand the claims and the embodiments described above. Among them:

[0074] Figure 1 is an axial plan view of the delivery chamber of the pump;

[0075] Figure 2 is an isometric view of an end side of the pump on which the bead gasket of the first exemplary embodiment is arranged;

[0076] Figure 3 is an axial plan view of the end side of the pump including the bead liner;

[0077] Figure 4 is a pump disposed in the receiving device;

[0078] Figure 5 The bead liner of the first exemplary embodiment is in an expanded state;

[0079] Figure 6 The bead liner of the first exemplary embodiment is in a folded and secured state;

[0080] Figure 7 is a longitudinal cross-section of a bead liner of the first exemplary embodiment;

[0081] Figure 8 is a schematic diagram of a bead liner of a first exemplary embodiment;

[0082] Fig. 9 is a longitudinal section of the folded portion of the bead liner;

[0083] Fig.10 is the folded part in the unfolded state;

[0084] Fig.11 is a retaining device of the bead liner of the first exemplary embodiment before establishing retaining engagement;

[0085] Fig.12 is a holding device while the engagement is being established;

[0086] Fig.13 is a retaining device in retaining engagement;

[0087] Fig.14 is a first variant of the holding device;

[0088] Fig.15 is a second variation of the holding device;

[0089] Fig.16 is a bead liner of a second exemplary embodiment;

[0090] Fig.17 is a retaining device of the bead liner of the second exemplary embodiment before establishing retaining engagement;

[0091] Fig.18 is a retaining device of a second exemplary embodiment in retaining engagement;

[0092] Fig.19 is a longitudinal section of the retaining device of the second exemplary embodiment in retaining engagement; and

[0093] Fig. 20 is a plan view of a retaining device of a second exemplary embodiment in retaining engagement.

[0094] Description of Reference Numerals

[0095] 1 Pump housing 2 Housing peripheral wall 3 Housing end wall

[0096] 4 Shell end wall 5 Delivery chamber 6 Entrance

[0097] 7 Inlet 8 Outlet 8' Connecting channel

[0098] 9 outlet 9' connecting channel 10 conveying component

[0099] 11 rotor 12 blades 13 drive shaft

[0100] 14 housing outer end surface 15 coil spring 16 positioning element

[0101] 17 connecting element 18 recess 19 driving wheel

[0102] 20 cushion layer 21 gasket ring 22 gasket ring

[0103] 23 Hardened structure 24 Hardened structure 25 Channel

[0104] 26 curved portion 27 cavity 28 fastening structure

[0105] 29 Retaining element 29' Improved retaining element 30 Pad layer

[0106] 31 washer ring 32 washer ring 33 hardened structure

[0107] 34 hardening structure 35 channel 36 bending part

[0108] 37 Folded portion 38 Pre-molded fold 39 Complementary retaining element

[0109] 39' Improved complementary retaining element 40 receiving device

[0110] 41 Pressure port 42 Pressure port 43 Radial gasket

[0111] 44 accommodating end surface 45 low pressure space 46 radial gasket

[0112] 47 - 48 - 49 -

[0113] 50 channel 51 holding element 52 curling portion

[0114] 53 protrusion 54 abutment point 55 complementary retaining element

[0115] 56 Curled portion 57 Protruding portion 58 Adjacent point

[0116] F Folding axis R Rotation axis S Bead gasket DETAILED DESCRIPTION

[0117] Figure 1 The pump is shown in an axial view of the pump housing 1. A delivery chamber 5 is formed in the pump housing 1. The pump housing 1 comprises a housing peripheral wall 2 surrounding the delivery chamber 5 and housing end walls axially delimiting the delivery chamber 5 at two end sides, one of which can be seen in the figure. In order to show the interior of the delivery chamber 5, the pump housing 1 is provided with a housing circumferential wall 2 and a housing end wall 4. Figure 1 In the embodiment, another housing end wall has been removed.

[0118] The pump is configured as a rotary pump and comprises a rotor 11 rotatable about an axis of rotation R in a delivery chamber 5 and a plurality of blades 12 guided in grooves of the rotor 11 so that the blades 12 can move radially or at least substantially radially, as is common in vane pumps. The rotor 11 and the blades 12 together form a delivery member 10 of the pump, which is formed as an impeller in the exemplary embodiment. The inner circumference of the housing peripheral wall 2 comprises guide surfaces for the blades 12, against which the blades 12 are pressed outwardly when the delivery member 10 rotates. When the rotor 10 rotates, the guide surfaces define how far the blades 12 protrude beyond the outer circumference of the rotor 11, the blades 12 outlining the delivery unit formed in the delivery chamber 5 in the circumferential direction. The contour of the guide surface of the housing peripheral wall 2 is selected so that when the delivery member 10 rotates, the delivery unit periodically increases in size on the low-pressure side of the delivery chamber 5 and decreases in size again on the high-pressure side of the delivery chamber 5, so that the fluid flowing into the delivery chamber 5 through the inlet on the low-pressure side of the delivery chamber 5 is discharged as pressure fluid through the outlet on the high-pressure side of the delivery chamber 5 at an increased pressure. In an advantageous embodiment, the pump is configured to suck the fluid through the inlet, for example against gravity.

[0119] In order to be driven in rotation, the rotor 11 is non-rotatably connected to a drive shaft 13 which passes through the housing end wall 4 and the rotor 11 and extends into the housing end wall 4. Figure 1 The drive shaft 13 is connected to the drive shaft 13 in a blind hole of the housing end wall, not shown in the figure. The drive part of the drive shaft 13 protrudes outward beyond the housing end wall 4 and can be driven to rotate. The drive wheel can be connected to the drive shaft 13 non-rotatably at the drive part, and the drive wheel is, for example, a pulley for belt drive, a sprocket for chain drive, or a gear for gear drive.

[0120] The housing peripheral wall 2 is formed as a closed ring, while the housing end walls 3 and 4 are each plate-shaped. In a first angular range extending on the low-pressure side of the first working flow, the housing peripheral wall 2 includes a cavity on each of the two end sides to form a first inlet 6. In another angular range extending on the low-pressure side of the second working flow, the housing peripheral wall 2 also includes a second cavity on each of the two end sides to form a second inlet 7 ( Figure 1 The fluid can flow into the delivery chamber 5 via the cavity on the end side in the housing wall 2, namely via the first inlet 6 and the second inlet 7 ( Figure 1 ). The housing peripheral wall 2 also includes a cavity on its outer circumference in each of the angular ranges of the inlet 6 and the angular range of the inlet 7, and the cavities on the circumference each extend axially from a cavity on one end side to an axially opposite cavity on the other end side. The cavities on the circumference connect the cavities of the first inlet 6 on the two end sides and the cavities of the second inlet 7 on the two end sides on the opposite sides, so that a large-volume first inlet 6 and an equally large-volume second inlet 7 are obtained. The housing end walls 3 and 4 can each be provided with an associated cavity in order to increase the flow cross-section of the inlet 6 and the flow cross-section of the inlet 7.

[0121] The housing end wall 4 comprises a flange for assembling the pump. In the assembled state, the pump housing 1 is fixed to the receiving device in the region of the flange.

[0122] A radial liner 43 is arranged on the outer periphery of the pump housing 1. In this exemplary embodiment, it is accommodated in a groove around the outer periphery of the housing end wall 4. The radial liner 43 is used to separate the low-pressure space from the external environment of the pump at the installation point. In the assembled state, the low-pressure space surrounds the pump housing 1 on the outer periphery.

[0123] The pump is a multi-flux pump, in the exemplary embodiment a dual-flux pump, i.e. it comprises a first working flux and a second working flux. Accordingly, the delivery chamber 5 comprises a first inlet 6 and a first outlet for the first working flow and a second inlet 7 and a second outlet for the second working flow. When the pump is in operation, the delivery member 10 is in Figure 1 The pressure outlet is located at Figure 1 The first connecting channel extending axially through the housing peripheral wall 2 on the high-pressure side of the first working flow is marked 8', and the second connecting channel extending axially through the housing peripheral wall 2 on the high-pressure side of the second working flow is marked 9'. The connecting channels 8' and 9' connect the pressure space formed in the area of ​​the housing end wall 4 to the axially opposite side of the pump housing 1. Figure 1 The pressure outlet of the housing end wall is not shown.

[0124] Figure 2The pump is shown in an isometric view in a pre-assembled state on the outlet side of the pump facing the end. The outlet side is formed on the side of the first housing end wall 3 facing the outward end, which is Figure 1 Not shown, but in Figure 2 The bead gasket S and the disc spring 15 are arranged on the side of the housing end wall 3 facing the outer end, and the first outlet and the second outlet appear on the side of the housing end wall 3 facing the outer end, and the bead gasket S covers these pressure outlets. Figure 1 The connecting channels 8 ′ and 9 ′ visible in FIG. 8 are assigned to the pressure outlets, wherein the connecting channel 8 ′ communicates with a first outlet through the housing end wall 3 and the connecting channel 9 ′ communicates with a second outlet likewise through the housing end wall 3 .

[0125] The bead gasket S includes a plurality of gasket rings extending around the inner region of the bead gasket S, and the fluid can flow through the inner region defined by the gasket rings on the radial outside. Figure 2 2 and 3. The gasket ring 21 and the gasket ring 22 can be seen in FIG. The gasket ring 21 surrounds an inner region of the bead gasket S axially opposite to the first outlet and overlaps the first outlet in an axial view. The gasket ring 22 surrounds another inner region of the bead gasket S axially opposite to the second outlet and overlaps the second outlet in an axial view.

[0126] The beaded edge gasket S is a multi-layer gasket, in the exemplary embodiment a double-layer gasket, wherein two gasket layers are connected to each other by one or more folded portions 37, wherein one gasket layer includes a retaining element 29 and the other gasket layer includes a complementary retaining element 39, wherein the retaining element 29 and the complementary retaining element 39 are retained in engagement with each other and prevent the gasket layers from separating from each other in the retained engagement.

[0127] The wall structure of the pump housing 1, namely the housing peripheral wall 2, the first housing end wall 3 and the second housing end wall 4, together define a delivery chamber 5 ( Figure 1 ). The housing end walls 3 and 4 respectively abut against the housing peripheral wall 2 in an axial contact manner. Advantageously, the housing peripheral wall 2 can be loosely connected to the housing end walls 3 and 4 (ie not in a materially matched manner).

[0128] The housing peripheral wall 2 and the housing end walls 3 and 4 are held together in an axially layered assembly manner in the preassembled pump unit by a positioning and retaining device. The positioning and retaining device comprises a first positioning element 16 and a second positioning element 16, which are Figure 1. In principle, one positioning element 16 is also sufficient, which is preferably a central positioning element. The respective positioning element 16 protrudes in the axial direction from the second housing end wall 4 in the shape of a rod, protrudes in the axial direction through the housing peripheral wall 2 and also through the first housing end wall 3. During preassembly, the housing peripheral wall 2 and the first housing end wall 3 slide along the positioning element 16 towards the housing end wall 4.

[0129] The bead liner S is held on the pump housing 1 by means of a positioning and retaining device. The bead liner S comprises a central channel which slides onto an axial protrusion on the outer end side of the housing end wall 3 during preassembly, thereby allowing the bead liner S to be centered during assembly. The bead liner S is held on the pump housing 1 by a threaded connection and / or a clamping connection and / or a similar engagement connection. To this end, the positioning and retaining device comprises one or more connecting elements 17, such as one or more screws and / or one or more clamping elements. The bead liner S comprises a sheet-like fastening structure 28 protruding from the outer periphery of the bead liner S, the fastening structure 28 having a channel passed by the connecting element 17, the connecting element 17 being connected and engaged with the positioning element 16, thereby holding the housing walls 2, 3 and 4 together with the bead liner S as a preassembled pump unit.

[0130] In the pre-assembled state, the disc spring 15 is likewise held on the outer end side of the housing end wall 3 , in particular by means of a bead washer S. The bead washer S can engage axially behind the disc spring 15 , so that the inner circumference of the disc spring 15 extends at least partially and preferably only partially in the remaining axial gap between the housing end wall 3 and the bead washer S and is thus loosely held between the housing end wall 3 and the bead washer S.

[0131] The disc spring 15 is designed to exert an axial spring force on the pump housing 1 when the pump is installed, so as to press the housing end walls 3 and 4 axially against the housing peripheral wall 2 and thus keep the delivery chamber 5 sealed. The disc spring 15 can also be used to separate the outlet from the low-pressure side of the pump. In addition to the bead gasket S, it can also be formed as an axial gasket.

[0132] Figure 3 is a plan view of the pump end side on which the bead liner S is arranged, and shows the course of the longitudinal section AA. Figure 3 , the longitudinal section AA extends in a straight line from the left side toward the center region, wherein it extends offset by a small distance relative to the rotation axis R. In the middle region, the longitudinal section AA jumps to the level of one of the positioning elements 16 or the coupling elements 17 and intersects it, then jumps back into the middle region, but now exactly at the level of the rotation axis R, and extends from the reset position in a straight line to the right and further through the pump.

[0133] Figure 4 Shows Figure 3 4. The longitudinal section AA of the pump in FIG. 4 is shown, but in the assembled state. The pump is arranged on the receiving device 40 and the pump is arranged to first extend into the receiving recess of the receiving device 40 together with the disc spring 15 and the bead liner S. The mounting flange of the housing end wall 4 of the pump abuts the receiving device 40 and the pump is fastened to the receiving device 40 in the region of the flange, for example by a screw connection.

[0134] The port side of the pump first extends into the receiving device 40 , and the housing outer end surface 14 of the housing end wall 3 and the receiving end surface 44 of the receiving chamber bottom of the receiving device 40 are opposite to each other with a small axial spacing (ie, axial gap).

[0135] The low-pressure space 45 formed on the outer periphery of the pump housing 1 is delimited by the inner periphery of the accommodating device 40 on the radial outside, by the radial liner 43 on one axial end, and by another radial liner 46 on the other axial end. When the pump is running, the fluid flows through the low-pressure space 45 and the inlets 6 and 7 ( Figure 1 and Figure 2 ) enters the delivery chamber 5. The low-pressure side of the pump includes the low-pressure space 45, the inlets 6 and 7, and the low-pressure side of the delivery chamber 5.

[0136] On the receiving end face 44 on the high-pressure side of the pump, there is a first pressure port 41 and a second pressure port 42, through which the fluid can be discharged axially. Figure 1 As explained on the basis of , the fluid is discharged from the first working flux in the region via the first outlet 8 through the housing end wall 3, and the fluid is discharged from the second working flux in the region via the second outlet 9 also through the housing end wall 3. Figure 1 The connecting channels 8' and 9' shown in the figure are connected to the corresponding pressure outlets, that is, the connecting channel 8' is connected to the first outlet 8, and the connecting channel 9' is connected to the second outlet 9. The pressure outlets 8 and 9 extend through the shell end wall 3 and enter the grooves of the shell end wall 3 on the shell outer end surface 14 of the latter. These grooves can be Figure 3 4 and 42. The first outlet 8 of the pump is axially opposite to the first pressure port 41, and the second outlet 9 of the pump is opposite to the second pressure port 42. When the pump is running, the fluid of the first working flux is discharged through the first outlet 8 and the first pressure port 41, and the fluid of the second working flux is discharged through the second outlet 9 and the second pressure port 42.

[0137] The bead gasket S is arranged in an axial gap maintained between the housing outer end surface 14 and the accommodation end surface 44 , and separates the first outlet 8 and the first pressure port 41 from the second outlet 9 and the second pressure port 42 .

[0138] It can also be seen that one of the positioning elements 16 and the bead liner S are fastened by means of this positioning element 16. The arrangement is identical to that of the other positioning element 16, the end of the positioning element 16 facing the bead liner S comprising an axial recess 18, for example a blind hole. The connecting element 17 is located in one of the fastening structures 28 ( Figure 2 ) in the region relative to the housing end wall 3 from the outside through the bead liner S and into the recess 18, where it is connected and engaged with the positioning element 16. The connecting element 17 and the connection method can be implemented as a fastening screw and a threaded connection, respectively, for example.

[0139] When the pump is assembled, the disc spring 15 is axially supported on the accommodating end face 44 and acts axially on the outer end face 14 of the housing with its spring force, so that the disc spring 15 presses the housing end wall 3 against the housing peripheral wall 2 and presses the housing peripheral wall 2 against the housing end wall 4 with the spring force, thereby achieving axial sealing and tight assembly of the housing end walls 3 and 4 and the housing peripheral wall 2 and ensuring that the delivery chamber 5 is sealed.

[0140] Preferably, but only as an example, the inner circumference of the disc spring 15 contacts the outer end face 14 of the housing, and the outer circumference contacts the receiving end face 44. Thus, the bead gasket S can be engaged behind the disc spring 15 with its inner circumference facing the receiving end face 44 in the axial direction, and hold it on the pump housing 1 in the pre-assembled state ( Figure 2 ).

[0141] The disc spring 15 surrounds the outlet 8 and the outlet 9 in a continuous, complete circumference and independent arc. It can be improved into an additional axial gasket and separate the first outlet 8 and the second outlet 9 from the low-pressure side of the pump, especially in the exemplary embodiment, from the low-pressure space 45. It can replace the radial gasket 46, and in this modification, it can replace the gasket closest to the low-pressure side when viewed from the high-pressure side. However, it can also be improved into an axial gasket and provided in addition to the radial gasket 46, and support the latter to seal the high-pressure side from the low-pressure side. However, the prerequisite is that when the pump is assembled, the disc spring 15 is supported toward the two axial sides via the gap on the end wall, and the end wall extends continuously over the entire circumference without interruption.

[0142] Figure 5 , Figure 6 and Figure 7 Each shows the bead gasket S by itself and not assembled. Figure 5 An axial plan view of a planar projection of the bead liner S is shown. Figure 6 and Figure 7 The bead gasket S is shown when folded and secured to prevent dispersion. Figure 6 1 is a plan view on the end face side of the bead liner S, which faces axially toward the housing end wall 3 . Figure 7 yes Figure 6 Longitudinal section CC shown in .

[0143] The bead cushion S is formed as one piece. It includes a first cushion layer 20, a second cushion layer 30 and a folded portion 37. Figure 5 In the planar projection of FIG. 1 , the backing layers 20 and 30 are placed side by side with each other and connected to each other by exactly two folded portions 37. The bead gasket S is not folded. In this plan view, the folding axis F passes through the folding portion 37, and when the folding portion 37 is folded, the backing layers 20 and 30 are pivoted toward each other about the folding axis F until they are folded and axially opposite to each other.

[0144] The folded portions 37 together form a folded region of the bead gasket S. Before folding, the cushioning layers 20 and 30 protrude away from each other from the folded region in the shape of wings. When measured parallel to the folding axis F, the cushioning layers 20 and 30 are significantly wider than the folded region formed by the folded portions 37. The unfolded bead gasket S is provided with a cavity 27 in the folded region between the cushioning layers 20 and 30, through which the two folded portions 37 are spaced apart from each other along the folding axis F, so that the cavity 27 reduces the width of the folded portions 37, which in this exemplary embodiment are each molded as a narrow strip measured along the folding axis F.

[0145] In the unfolded state, one of the fastening structures 28 protrudes freely into the cavity 27 between the folded parts 37, and the fastening structure 28 can be directly formed into the cavity 27 by, for example, stamping. The other fastening structure 28 protrudes freely outward from the opposite circumferential portion of the cushion layer 20 facing away from the folded parts 37, each fastening structure 28 comprising a channel ( Figure 2 and Figure 4 ).

[0146] The bead liner S comprises a retaining element 29 and a complementary retaining element 39 which are movable into retaining engagement with each other. Figure 5 In a plane projection of the folding plane, i.e. before folding, the retaining element 29 and the complementary retaining element 39 are arranged opposite to each other across the folding axis F so that they pivot towards each other when folding. In the retaining engagement, they prevent the cushioning layers 20 and 30 from being separated from each other. The retaining element 29 is part of the first cushioning layer 20, and the complementary retaining element 39 is part of the second cushioning layer 30, the retaining element 29 protruding freely from the root end and being flexurally elastic. It is formed as a spring tongue. The complementary retaining element 39 is formed by an edge portion on the peripheral edge of the second cushioning layer 30, and the retaining element 39 includes a portion of the free peripheral edge of the cushioning layer 30 and extends slightly from the free peripheral edge into the area of ​​the cushioning layer 30 close to the edge.

[0147] In contrast to the total of two folds 37 of the exemplary embodiment, the folding region can in principle also comprise more folds, each of which is advantageously a narrow fold, comparable to the aforementioned fold 37. In another variant, the cushioning layers 20 and 30 can also be connected to each other by only one fold. However, dividing them into two folds 37 is advantageous for precisely defining the folding axis F and thus the relative position of the cushioning layers 20 and 30 when folded. Another advantage is that the fastening structure 28 can be manufactured by forming the cavity 27 between the folds 37, which saves material compared to fastening structures located outside the folding region.

[0148] In plan view, the retaining element 29 is arranged in the region of the fastening structure 28 which is at a distance from the folded portion 37. In the exemplary embodiment, it is formed in the root region of the fastening structure 28.

[0149] In order to facilitate folding, in particular in order to precisely define the folding axis F, the folding portions 37 are each provided with a pre-moulded fold 38 , which may be, for example, an embossing or a projection extending along the folding axis F.

[0150] The first backing layer 20 includes a first gasket ring 21, which Figure 2 , and surrounds the first inner region in an axial plan view. In a plan view, the gasket ring 21 is the smallest gasket ring relative to the first inner region, and closes (ie completely surrounds) the first inner region. The gasket ring 21 is a half-bead.

[0151] Compared to conventional gasket rings, the first gasket ring 21 is hardened in the first inner region. It is hardened (rigidified) by a first hardened structure 23 extending circumferentially from the inner edge of the gasket ring 21 into the inner region. The hardened structure 23 can be formed as a flat thin disk, or as in the exemplary embodiment, as a thin groove structure with an axial shallow bend. It includes a plurality of channels 25, which are arranged side by side with each other and through which fluid can flow when the pump is running. The hardened structure 23 extends along the entire inner circumference of the gasket ring 21 and uniformly reinforces the gasket ring 21 radially inwardly over the entire inner circumference.

[0152] The second backing layer 30 includes a second gasket ring 31 surrounding the second inner region in a plan view. In an axial view, the gasket ring 31 forms the smallest gasket ring relative to the second inner region and closes (i.e., completely surrounds) the second inner region. The gasket ring 31 is hardened radially inwardly, i.e., in the second inner region, in a manner similar to the gasket ring 21. A second hardening structure 33 is used to harden the second gasket ring 31, which can be formed as a flat thin disk, or as in the exemplary embodiment, as an axially shallowly curved thin groove structure, and the second hardening structure 33 includes a channel 35 for a fluid in a manner similar to the first hardening structure 23.

[0153] The first backing layer 20 includes another third gasket ring 22, which is Figure 2 As shown in the figure, the gasket ring 22 surrounds the third inner area in an axial plan view. In the axial view, the gasket ring 22 forms the smallest gasket ring relative to the third inner area and closes (i.e. completely surrounds) the third inner area. The gasket ring 22 is also hardened in its inner area. The third hardened structure 24 can be formed as a flat thin disk, or as a thin groove structure with an axial shallow bend as in the exemplary embodiment, for reinforcing the third gasket ring 22, and the hardened structure 24 extends uniformly over the entire inner circumference of the third gasket ring 22 so as to harden radially inwardly on the inner circumference. The third hardened structure 24 is also provided with a plurality of channels 25 for the fluid transported by the pump, which are arranged side by side with each other in a manner similar to the first hardened structure 23.

[0154] The first gasket ring 21 and the third gasket ring 22 are arranged side by side in a top view, so that the assigned inner areas are also arranged side by side and spaced apart from each other. In this exemplary embodiment, the gasket rings 21 and 22 also extend at a distance from each other. The central channel of the gasket layer 20 for placing the bead gasket S in the folded state in the center of the pump housing 1 is located, for example, between the gasket rings 21 and 22.

[0155] Finally, the second lining layer 30 includes a fourth gasket ring 32 surrounding the fourth inner area in a plan view. In a plan view, the gasket ring 32 forms the smallest gasket ring relative to the fourth inner area and closes (i.e. completely surrounds) the fourth inner area. The gasket ring 32 is also hardened in its inner area. The fourth hardening structure 34 can be formed as a flat thin disk, or as a thin groove structure with an axial shallow bend as in the exemplary embodiment, for hardening the fourth gasket ring 32. The hardening structure 34 extends uniformly over the entire inner circumference of the fourth gasket ring 32 so as to harden uniformly radially inward on the inner circumference. The fourth hardening structure 34 is also provided with a plurality of channels 25 for the fluid transported by the pump, which are arranged side by side with each other in a manner similar to the first hardening structure 23.

[0156] The second gasket ring 31 and the fourth gasket ring 32 are arranged side by side with each other in a top view, so that the relevant inner areas are also arranged side by side with each other and spaced apart from each other. In the exemplary embodiment, the gasket rings 31 and 32 also extend at a distance apart from each other. The central channel of the lining layer 30 is located, for example, between the gasket rings 31 and 32, and the central channel is used to center the bead gasket S on the pump housing 1 after being folded.

[0157] In the folded state, the first gasket ring 21 and the second gasket ring 31 overlap in their entire contours in an axial top view, so that the inner areas surrounded by the gasket rings 21 and 31 overlap each other at least substantially completely. The second gasket ring 31 is molded as a half-gasket in a corresponding manner to the first gasket ring 21, and the gasket rings 21 and 31 are axially open to each other starting from their outer circumference and toward a common first inner area, so that the axial spring displacement of the bead gasket S in the area of ​​the gasket rings 21 and 31 is increased compared to the corresponding single gasket rings 21 and 31, and as expected, the increase in the axial spring displacement is advantageous for compensating for changes in the axial width of the gap to be sealed.

[0158] In the folded state, the third gasket ring 22 and the fourth gasket ring 32 overlap in their entire contours in an axial top view, so that the inner areas surrounded by the gasket rings 22 and 32 overlap each other at least substantially completely. The gasket rings 22 and 32 are also molded as half-gaskets. The gasket rings 22 and 32 are axially open to each other starting from their outer circumference and toward the common second inner area, so that the axial spring displacement of the bead gasket S in the area of ​​the gasket rings 22 and 32 is increased compared to the corresponding single gasket rings 22 and 32, which is advantageous for compensating for changes in the axial width of the gap to be sealed, as desired.

[0159] In the unfolded state, the gasket rings 21 and 31 on the one hand and / or the gasket rings 22 and 32 on the other hand can in particular be mirror-symmetrical about the folding axis F so that they are axially flush over their entire contour when the bead liner S is folded and fixed in engagement.

[0160] In an additional function, the stiffening structures 23, 24, 33 and 34 are also resistance structures. In this exemplary embodiment, they are each perforated with a large number of small channels 25 and 35, such as channel holes. The stiffening structures 23, 24, 33 and 34 each form a flow resistance for the fluid to be conveyed. When the pump is started, in particular when the pump is cold and the fluid is correspondingly viscous, the flow resistance ensures that the conveying member 10 ( Figure 1 ) are pressed radially outwards. To achieve this effect, the fluid delivered by the pump is applied to the underside of the blades 12 in the so-called secondary blade area. The stiffening structures 23, 24, 33 and 34 serve to ensure that this secondary blade area is supplied with pressurized fluid.

[0161] The bead gasket S is a sheet metal structure. It can in particular be a sheet steel structure and preferably a spring steel structure. However, the bead gasket S can in principle also be a plastic structure, for example an organic sheet structure. However, sheet steel (in particular spring steel) is preferred. The backing layer 20 and / or the backing layer 30 can (each) be coated with an elastic backing material, although it may be advantageous to omit the coating and embody the bead gasket as a pure metal bead gasket.

[0162] Advantageously, the bead gasket S is mounted at the mounting point with an axial biasing force. The biasing force is conveniently selected so that it ensures sufficient spring force for the sealing strength under all mounting conditions (i.e. with respect to unavoidable component tolerances and mounting tolerances and with respect to variations in the axial width of the gap associated with temperature and / or pressure variations).

[0163] In a preferred embodiment, the bead gasket S is designed relative to the mating pairs of gasket rings 21 and 31 and 22 and 32 so that it can compensate for changes in the axial gap width of at least 0.1 mm or at least 0.2 mm, preferably 0.3 mm or more, and ensure adequate sealing within the corresponding range of changes in the axial gap width.

[0164] The bead spacer S is arranged in the indirect line of force to the disc spring 15 ( Figure 4 ). When the gap width decreases, the disc spring 15 absorbs most of the axial force passing through the gap. Therefore, the disc spring 15 is designed so that it can compensate for changes in the axial gap width of at least 0.1 mm or at least 0.2 mm, preferably 0.3 mm or more, and elastically absorb most of the axial force acting on the joint within the corresponding change range of the axial gap width, and optionally produce a seal relative to the low-pressure space 45.

[0165] Figure 6 Shown when folded and ready to be assembled in the pump housing 1 ( Figure 2 ) on the bead liner S. The liner layers 20 and 30 are folded about the folding axis F and one is located above the other, preferably one is located on top of the other in this exemplary embodiment. The retaining element 29 and the complementary retaining element 39 are retained in engagement with each other. Figure 6 The axial plan view of the folded bead liner S on the liner layer 30 is shown. Figure 2 The preassembled pump unit shown faces the housing end wall 3. When retaining engagement, the retaining element 29 engages behind the complementary retaining element 39 in the axial direction. Figure 6 In plan view of , the free peripheral edge of the spacer layer 30 , which forms part of the complementary retaining element 39 , is covered by the retaining element 29 .

[0166] The retaining engagement structure is located opposite the folding area across the central area of ​​the folded bead pad S. A section perpendicular to the folding axis F extends between the folded portions 37 and through the retaining engagement. If two straight lines are imagined, which intersect on the folded bead pad in plan view and divide the bead pad S into four sectors, so that each folded portion 37 extends completely in the first sector and each retaining engagement structure is formed in the second sector in plan view, wherein the first sector and the second sector are mirror images of each other at the intersection of the two straight lines, it is in principle advantageous if the two sectors each extend over a sector angle of at most 90° or at most 60°.

[0167] In order to obtain uniform contact on the peripheral edges of the mutually abutting cushioning layers 20 and 30, the cushioning layers 20 and 30 are each pre-molded so that they are concave relative to each other towards their respective peripheral edges in the folded state even before the holding engagement has been established. In this exemplary embodiment, this concavity is achieved by providing each of the cushioning layers 20 and 30 with a curved portion extending in a central region. Figure 6 In a plan view of , the bend 36 in the backing layer 30 can be seen as a straight bend line through the backing layer 30, the bend 36 and the bend of the other backing layer 20 each extending approximately perpendicular to the folding axis F. The gradient is selected so that the bends extend from the peripheral edge to the peripheral edge through the central area of ​​the beaded gasket S, but only on the outside of the gasket ring, Figure 6 The outer side of the middle gasket rings 31 and 32. In a cross section parallel to the folding axis F, which extends in the axial direction from the plane of the plan view, the cushion layers 20 and 30 form a very flat diamond when folded, but are not yet fixed, wherein the cushion layers 20 and 30 are not yet in contact with each other at the outer circumferential edges or at least not yet axially tensioned.

[0168] Figure 7 Shows Figure 6 Longitudinal section CC of a middle bead liner S. Due to its multi-layer structure, the axial spring displacement of the bead liner S is longer than that of the bead liner of a single-layer embodiment, which can be particularly Figure 7 It can also be seen that the stiffening structures 24 and 34 are convex relative to each other so that their axial distance decreases in a central region within the washer rings 22 and 32 where, in this exemplary embodiment, the stiffening structures 24 and 34 axially abut each other.

[0169] Figure 8Purely schematically, an axial section of a bead gasket S parallel to the folding axis F is shown. The bead gasket S is folded. The gasket layers 20 and 30 are axially opposite each other, the holding joint has not yet been established and no external forces act on the gasket layers 20 and 30. When not subjected to any load in this way, the two gasket layers 20 and 30 are pre-molded in a concave shape relative to each other. The gasket layers 20 and 30 are pre-molded in that they each include a small bend 26 and 36 in a central area and taper from the central area towards each other at an acute angle, extending outwards from the respective bend 26 and 36 to the outer circumferential edge. If the shaped gasket ring, such as Figure 8 As shown in the schematic diagram of FIG. 1 , the liner layers 20 and 30 together form a flat rhombus. However, Figure 8 is overstretched. In the unfolded state ( Figure 5 ) is barely recognizable. However, in the corresponding plan view, the corresponding bends 26 and 36 can be seen as thin inflection lines. Figure 5 The inflection lines 26 and 36 are not shown. In a planar projection of the beaded gasket, they can form a straight line extending through the central area and always between the gasket rings. However, the bends 26 and 36 can also be offset relative to each other in a plan view or at an obtuse angle to each other if, for example, the bends 26 and 36 can only extend beyond the gasket rings when the gasket layers 20 and 30 are unfolded.

[0170] Because they are pre-concave molded, when establishing the holding engagement, the lining layers 20 and 30 are pulled toward each other in the region of the bends 26 and 36 so that they first come into axial contact on the peripheral edges. Thus, the concave pre-molding hinders separation of the peripheral edges.

[0171] Fig. 9 and Fig.10 One of the folded portions 37 is shown in enlarged detail. Fig. 9 It is shown that when the folded portion 37 is Figure 6 The folded portion 37 when folded in the longitudinal section BB. Fig.10 A longitudinal section of a folded portion 37 is also shown, but before it is folded. As mentioned above, each folded portion 37 is provided with a pre-molded folded portion 38 in order to more accurately define the folding axis F. The pre-molded folded portion 38 is a local protrusion which can be formed together with the gasket rings 21, 22, 31 and 32 by deep drawing during the molding of the gasket rings, or can also be molded in a previous or subsequent step.

[0172] Fig.11 , Fig.12 and Fig.13 From Fig.11 via Fig.12 Proceed to Fig.13 In the form of a sequence, the retaining element 29 and the complementary retaining element 39 establishing a retaining engagement are shown.

[0173] Fig.11 The initial state associated with establishing the holding engagement is shown. The backing layers 20 and 30 have been folded. The holding element 29 formed as a spring tongue is not subjected to any load and extends in a planar manner next to the backing layer 20, the backing layer 30 being held at a distance from the holding element 29 in the axial direction in the region of the complementary holding element 39 or being intrinsically separated from the backing layer 20 at the circumferential edge in the region of the complementary holding element 39.

[0174] Fig.12 The next step in the sequence is shown, in which the retaining element 29 is bent out of its backing layer 20 towards the complementary retaining element 39 and via its free end (the peripheral edge of the backing layer 30) using, for example, a pin-shaped tool of an automatic assembly machine, so that a path is made for the complementary retaining element 39, and the backing layer 30 can be pressed against the backing layer 20 in the region of the complementary retaining element 39 by means of another tool. If the retaining element 29 is subsequently released, it springs back elastically and presses the complementary retaining element 39 axially against the backing layer 20 with a tensioning force based on the elasticity.

[0175] Fig.13 The backing layers 20 and 30 are shown in close proximity to the retaining element 29 and the complementary retaining element 39. The free end of the complementary retaining element 39, the free outer periphery of the shim layer 30, is located below the free end of the retaining element 29, as seen from the backing layer 20. In this rear engagement, the retaining element 29 supports the backing layer 30 on the backing layer 20 via the complementary retaining element 39, which prevents the backing layers 20 and 30 from being separated from each other. In the retaining engagement, the retaining element 29 presses on the complementary retaining element 39 due to its elastic deformation.

[0176] Fig.14The cushioning layers 20 and 30 are shown in close proximity to each other in a retaining engagement. The complementary retaining element of the cushioning layer 30 has been modified. The modified complementary retaining element is marked 39'. The improved complementary retaining element 39' is crimped so that its free end extends in the plane of the first cushioning layer 20 when it is in a retaining engagement. To this end, the second cushioning layer 30 is sharply deflected (delfect) towards the cushioning layer 20 in the region of the edge portion of the cushioning layer 20 opposite the retaining element 29, and is sharply retracted again when axially horizontal to the cushioning layer 20, thereby obtaining a complementary retaining element 39' in the form of a stepped profile. As in the exemplary embodiment, if the retaining element 29 is planar when not subject to any load, its free end will slightly protrude beyond the second cushioning layer 30 in the retaining engagement. In order to reduce this protrusion, in another further improvement, the retaining element 29 can also be crimped or rounded so that it is flush with the complementary retaining element 39' in the region of its free end in the retaining engagement.

[0177] Fig.15 The backing layers 20 and 30 are shown in close proximity and held in engagement, wherein the backing layer 20 includes a retaining element 29' which is in contact with the backing layer 20. Figures 11 to 13 When not under any load, the retaining element 29' protrudes out of the plane of its cushion layer 20, i.e., protrudes from the immediate vicinity of the cushion layer 20, away from the other gasket layer 30. In order to establish the retaining engagement, a tool is used to bend the retaining element 29' toward the complementary retaining element 39 and pass it under it, such as in combination with Figures 11 to 13 However, the degree of deformation required for the bending of the modified retaining element 29' is greater than for the retaining element 29. Therefore, when retaining the engagement, it acts on the complementary retaining element 39 with a greater axial tension.

[0178] Fig.16 The bead liner S of the second embodiment is shown in an isometric view on the liner layer 20. The bead liner S is folded, but not yet fixed. The folding process itself is complete and the liner layers 20 and 30 are axially opposite to each other, but are still slightly separated from each other in the outer peripheral area opposite the folded area. The bead liner S of the second exemplary embodiment differs from the first exemplary embodiment in the number and embodiment of the retaining elements and complementary retaining elements.

[0179] Unlike the first embodiment, the first cushion layer 20 comprises two retaining elements 51, and the second cushion layer 30 accordingly comprises two complementary retaining elements 55, which can be moved into retaining engagement in pairs. The retaining elements 51 and the complementary retaining elements 55 protrude freely outward from the peripheral edges of the respective cushion layers 20 and 30.

[0180] Fig.17 exist Fig.16 Detail X shows a pair of retaining elements 51 and complementary retaining elements 55 before establishing a retaining engagement. Fig.18 , Fig.19 and Fig. 20 The same pair of retaining element 51 and complementary retaining element 55 is shown in retaining engagement, wherein Fig.18 For perspective, Fig.19 is the axially extended cross section, Fig. 20 Axial plane view.

[0181] The retaining element 51 and the complementary retaining element 55 are curled relative to the axial direction. The respective retaining element 51 includes a curled portion 52, and the respective complementary retaining element 55 includes a curled portion 56. Through its curled portion 52, the respective retaining element 51 falls from the peripheral edge of the cushion layer 20 in the axial direction and is flush with the peripheral edge of the cushion layer 30. And in the other axial direction, the respective complementary retaining element 55 falls from the peripheral edge of the cushion layer 30 through its curled portion 56 and is flush with the cushion layer 20. The shapes of the curled portions 52 and 56 can be Fig.19 As can be seen most clearly in the cross-section of FIG. 5 , by means of the curling portions 52 and 56 , the retaining element 51 and the complementary retaining element 55 only widen the mutually adjacent lining layers 20 and 30 outwards in the retaining engagement without increasing the overall thickness in the vicinity of the retaining engagement.

[0182] Each retaining element 51 comprises a projection 53 which projects towards the associated complementary retaining element 55, thereby forming a retaining engagement. The complementary retaining elements 51 each comprise a projection 57 which projects towards the associated retaining element 51, thereby forming a retaining engagement. The retaining element 51 and the complementary retaining element 55 each comprise a recess on their sides facing each other in the circumferential direction, in order to receive the projections 53 and 57. Figures 17 to 20 As shown in the view, in particular Fig. 20 , the paired retaining elements 51 and complementary retaining elements 55 are axially located one above the other via projections 53 and projections 57, respectively, and are pressed against each other with elastic tension in order to tension the cushioning layers 20 and 30 relative to each other. In principle, it is sufficient for the retaining engagement of each pair of retaining elements 51 and complementary retaining elements 55 to include only one projection 53 or 57, provided that it overlaps in each case with the other engaging counterpart in the retaining engagement in order to act axially thereon.

[0183] The retaining element 51 and the complementary retaining element 55 also include abutment points 54 and 58 ( Fig. 20 ). The abutment points 54 and 58 are located between the peripheral edges of the respective cushioning layers 20 and 30 and the respective projections 53 and 57. The abutment points 54 and 58 are located in the region of the recesses.

[0184] In order to establish the retention engagement, the folded cushion layers 20 and 30 are offset relative to each other in the circumferential direction by slight elastic tensioning, so that the retaining element 51 and the complementary retaining element 55 are free from each other in the plan view. Then, in this state, the peripheral edges of the cushion layers 20 and 30 are pressed against each other at the retaining element 51 and the complementary retaining element 55, and then released relative to the circumferential direction, so as to abut against each other. The cushion layers 20 and 30 rebound in the circumferential direction, so that the protrusions 53 and 57 of the retaining element 51 and the complementary retaining element 55 overlap in pairs, thereby entering the retention engagement. Once the overlap is established, the cushion layers 20 and 30 can be released axially again. In order to facilitate tensioning and thus offset in the circumferential direction, the cushion layers 20 and 30 can each be provided with a channel 50, wherein the channel is axially flush in the folded state. For tensioning and offsetting, a rod-shaped tool can be inserted into the flush channel 50 and tilted relative to the axial direction.

[0185] Except for the differences described, the bead gasket S of the second embodiment is identical to the bead gasket S of the first embodiment.

Claims

1. A bead gasket (S) for sealing a gap between a first component (1) and a second component (40), the bead gasket (S) comprising: (a) a first backing layer (20) comprising a retaining element; (b) a second backing layer (30) comprising complementary retaining elements; as well as (c) one or more folded portions (37) connecting the first backing layer (20) and the second backing layer (30), (d) wherein the first cushion layer (20), the second cushion layer (30) and the corresponding folded portion (37) are formed as one body, and the first cushion layer (20) and the second cushion layer (30) are folded or can be folded onto each other by folding the corresponding folded portion (37) so that the first cushion layer (20) and the second cushion layer (30) face each other in the axial direction, and (e) wherein the retaining element and the complementary retaining element are held in engagement with each other based on form fit and / or friction fit to secure the first cushion layer (20) and the second cushion layer (30) against separation from each other, (f) wherein the first backing layer (20) and the second backing layer (30) including the retaining element and the complementary retaining element are formed continuously from a single piece of metal via one or more of the folded portions (37).

2. Bead liner (S) according to the preceding claim, wherein: In the retaining engagement, the retaining element and the complementary retaining element engage behind each other with respect to the axial direction and are pressed against each other in the axial direction by a tension force based on elastic deformation.

3. A bead liner (S) according to any one of the preceding claims, wherein: In the retaining engagement, the retaining element engages behind the peripheral edge of the second backing layer (30) with respect to the axial direction, or the complementary retaining element engages behind the peripheral edge of the first backing layer (20) with respect to the axial direction.

4. The bead gasket (S) according to claim 1, wherein: In plan view, the retaining element and / or the complementary retaining element protrudes freely from a root end and can be elastically bent to release the retaining engagement.

5. The bead gasket (S) according to claim 1, wherein: The retaining element and / or the complementary retaining element are bent circularly toward the free end and bent or curled back again, and wherein the retaining element extends out of the plane of the first backing layer (20) and into the plane of the second backing layer (30), and / or wherein the complementary retaining element extends out of the plane of the second backing layer (30) and into the plane of the first backing layer (20) so as to maintain the bead edge gasket (S) with a low thickness in the area of ​​the retaining joint.

6. The bead gasket (S) according to claim 1, wherein: In the axial plane perspective of the unfolded bead liner (S), the folding axis (F) of the bead liner (S) extends transversely relative to the axial direction in one or more of the folded portions (37); in the plane perspective along the folding axis (F), the corresponding folded portion (37) exhibits a folded portion width, and the bead liner (S) exhibits a maximum liner width measured along a direction parallel to the folding axis (F); and the maximum liner width is at least three times or at least five times the width of the corresponding folded portion.

7. The bead gasket (S) according to claim 1, comprising a first folded portion and a second folded portion, wherein: In an axial plane view on the unfolded bead liner (S), the folding axis (F) of the bead liner (S) extends between the folded portion (37) and the cavity (27) located between the folded portion (37), and the cavity (27) is completely free of material or only free of material in the area along the folding axis (F).

8. The bead gasket (S) according to claim 1, wherein: In an axial plane perspective, the respective folded portion (37) extends completely within a first sector of the folded bead liner (S), and the retaining engagement is formed in a second sector of the plane perspective, wherein the first sector and the second sector are described by two straight lines intersecting in the plane perspective and mirroring each other at the intersection of the two straight lines, and the sectors extend over a sector angle of at most 90° or at most 60°.

9. The bead gasket (S) according to claim 1, wherein: When the folding portion (37) has been folded up and before the retaining joint is established, the first cushion layer (20) and the second cushion layer (30) face each other axially, and the first cushion layer (20) and / or the second cushion layer (30) are concavely pre-molded in an axial plane parallel to the folding axis (F) and orthogonal to the first cushion layer (20) and the second cushion layer (30) until the first cushion layer (20) and the second cushion layer (30) are relative to the peripheral edge of the other of the first cushion layer (20) and the second cushion layer (30) in the absence of external force, so that the end-facing surfaces of the first cushion layer (20) and the second cushion layer (30) taper toward each other at an acute angle toward the peripheral edge of the corresponding cushion layer in these axial planes.

10. The bead gasket (S) according to claim 1, wherein: When the folding portion (37) has been folded and before the retaining engagement is established, the first backing layer (20) and the second backing layer (30) face each other axially, and the first backing layer (20) and / or the second backing layer (30) are bent in a folding plane, which is orthogonal to the folding axis (F) in an axial plane perspective and extends on the folded bead liner (S) through a central area of ​​the bead liner (S) and / or through the retaining element, and when viewed from the folding axis (F), the first backing layer (20) and / or the second backing layer (30) protrude away from the other of the first backing layer (20) and the second backing layer (30) in the absence of external force.

11. The bead gasket (S) according to claim 1, wherein: The first cushion layer (20) and the second cushion layer (30) are formed by deep drawing and punching.

12. The bead gasket (S) according to claim 1, wherein: The first gasket layer (20) includes a gasket ring, and the second gasket layer (30) includes a gasket ring; The gasket ring of the first gasket layer (20) surrounds an internal area through which fluid can flow in an axial plane view, and includes a gasket end face surface for axially contacting the first component (1) or the second component (40); the gasket ring of the second gasket layer (30) surrounds an internal area through which fluid can flow in an axial plane view, and includes a gasket end face surface for axially contacting the other of the first component (1) or the second component (40); the two internal areas at least partially overlap each other in a plane view; the gasket ring of the first gasket layer (20) and / or the gasket ring of the second gasket layer (30) are gasket rings.

13. The bead gasket (S) according to claim 12, wherein: The first liner layer (20) includes a hardening structure, which, in a planar perspective, extends from the liner ring of the first liner layer (20) to the internal region so as to harden the liner ring of the first liner layer (20), and / or, wherein the second liner layer (30) includes a hardening structure, which, in a planar perspective, extends from the liner ring of the second liner layer (30) to the internal region so as to harden the liner ring of the second liner layer (30).

14. The bead gasket (S) according to claim 13, wherein: At least one of the stiffening structures is raised relative to the stiffening structure axially facing thereto.

15. A pump for applying a fluid to a cell, the pump comprising: (a) A pump housing having the following characteristics - a housing peripheral wall (2) which surrounds the delivery chamber (5) of the pump, a housing end wall (3) having a housing outer end face (14) axially facing away from the conveying chamber (5), - an inlet (6) for said fluid, and - an outlet (8) for the fluid to flow out from the outer end surface (14) of the housing; (b) a delivery member (10) movable within the delivery chamber (5) to deliver the fluid from a low-pressure side of the pump including the inlet (6) to a high-pressure side of the pump including the outlet (8); as well as (c) a bead gasket (S) comprising a first gasket layer (20) and a second gasket layer (30), one of the first gasket layer (20) and the second gasket layer (30) being axially disposed on top of the other, (d) wherein: the first gasket layer (20) includes a first gasket ring (21), and the second gasket layer (30) includes a second gasket ring (31); in an axial plane perspective, the first gasket ring (21) surrounds a first inner region through which a fluid can flow, and, in an axial plane perspective, the second gasket ring (31) surrounds a second inner region through which a fluid can flow; and, in an axial plane perspective, the first inner region and the second inner region at least partially overlap each other; (e) wherein the first gasket ring (21) is a first gasket ring including a gasket end face surface for axial contact, and / or the second gasket ring (31) is a second gasket ring including a gasket end face surface for axial contact, (f) wherein one of the first gasket ring (21) and the second gasket ring (31) faces the outer end surface (14) of the housing in the axial direction and surrounds the outlet (8) in the plane view to seal the outlet (8), (g) wherein the bead gasket (S) comprises one or more folded portions (37) connecting the first gasket layer (20) and the second gasket layer (30), and the first gasket layer (20), the second gasket layer (30) and the corresponding folded portions (37) are formed as one body, and the first gasket layer (20) and the second gasket layer (30) are folded or can be folded onto each other by folding the corresponding folded portions (37) so that the first gasket layer (20) and the second gasket layer (30) face each other in the axial direction, and (h) The first backing layer (20) and the second backing layer (30) are continuously formed from a single piece of metal through one or more of the folded portions (37).

16. Pump according to the preceding claim, wherein The first gasket ring (21) and the second gasket ring (31) are respectively a first gasket ring and a second gasket ring, and the first gasket ring and the second gasket ring are axially expanded away from each other toward the corresponding surrounded inner area so that an increased axial spring displacement is obtained between the surfaces of the gasket ends axially facing away from each other.

17. The pump of claim 15, wherein: - the pump is arranged on the receiving device; - the receiving device comprises: a receiving recess and a base (44) of the recess; - at least one axial portion of the pump housing is arranged in the receiving recess so that the housing outer end surface (14) is located axially opposite to the base of the recess and an axial gap is formed; and - The bead gasket (S) seals the outlet (8) in the axial gap.

18. The pump according to claim 15, wherein When the pump is assembled, the bead gasket (S) exerts an axial spring force on the pump housing via the first gasket ring (21) and the second gasket ring (31) in an indirect force line to the spring device (15) or in a direct force line.

19. The pump according to claim 15, wherein The first gasket layer (20) includes a first hardening structure (23), which, in the plane view, extends from the first gasket ring (21) to the first inner region so as to harden the first gasket ring (21), and / or, wherein the second gasket layer (30) includes a second hardening structure (33), which, in the plane view, extends from the second gasket ring (31) to the second inner region so as to harden the second gasket ring (31).

20. The pump of claim 15, wherein: The bead liner (S) is a bead liner (S) according to any one of claims 1 to 14.

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