EP4341590A1

EP4341590A1 - Valve assembly

Info

Publication number: EP4341590A1
Application number: EP22729600.1A
Authority: EP
Inventors: Mihai Drienovsky; Deian Rasici; Alexandru Popa; Dmytro Rozputniak; Pavel-Sorin Han; Cosmin Ion BELIN; Robert-Marian CHITAC
Original assignee: Vitesco Technologies GmbH
Current assignee: Vitesco Technologies GmbH
Priority date: 2021-05-19
Filing date: 2022-05-18
Publication date: 2024-03-27
Also published as: WO2022243384A1

Abstract

The invention relates to a valve assembly, in particular for a gas line, in particular for a gas line of a fuel cell assembly and/or a motor vehicle drive assembly. The valve assembly has a housing (10) comprising a fluid line (12); and a valve which is arranged in the fluid line (12) and comprises a valve seat (42), a valve flap (16), and a valve opening. The valve flap (16) can be pivoted about a pivot axis between a closed position, in which the valve flap (16) lies against the valve seat (42) and closes the valve opening in a fluid-tight manner, and an open position, in which the valve flap (16) releases the valve opening, wherein the valve flap (16) defines the X-Y plane of a coordinate system (22) in the closed position, and the pivot axis is arranged at a distance to the X-Y plane and defines the Y direction of the coordinate system (22). The valve assembly has an aligning mechanism, by means of which the arrangement in which the valve flap (16) is in the closed position relative to the valve seat (42) can be aligned and fixed at least in the X direction.

Description

description

valve assembly

The invention relates to a valve arrangement, in particular for a gas line, in particular for a gas line of a fuel cell arrangement and/or a motor vehicle drive arrangement.

Valves for opening and closing lines, in particular gas lines, have to meet a wide range of requirements. In this way, when the valve is closed, a seal that is as perfect as possible should be achieved, and at the same time the valve should be able to be actuated with as little actuating force as possible. With a view to the service life, but also to avoid contamination, the lowest possible wear should be ensured in the area of the interacting sealing surfaces. If the valve arrangement is used for a hydrogen fuel cell, for example, the tightness when the valve is closed plays a particularly important role, because when the drive is switched off, the ingress of air or oxygen must be prevented in order to avoid corrosion of the fuel cell.

So-called butterfly valves are often used in order to meet the stated requirements as far as possible. In these, the valve flap performs a pivoting movement about a pivot axis arranged more or less centrally within the gas line. These can usually be actuated with relatively low actuating forces, but require a relatively high production cost in order to achieve optimal sealing and low abrasion.

A butterfly valve has become known from publication EP 2 299 151 A2, in which the pivot axis of a valve disk is offset in two directions. A surface forming the valve seat is partially conical. Document GB 2516094 A discloses a butterfly valve in which the pivot axis of a valve member is offset in two directions. A surface forming the valve seat is conical.

A butterfly valve has become known from publication WO 2014/175886 A1, in which the pivot axis of a valve member is offset in two directions. A blade-like edge running around the circumference is formed on the valve member and comes into contact with the valve seat in the closed position.

Butterfly valves for exhaust gas recirculation systems have become known from the publications US 2011/0272613 A1, US 2019/0203676 A1 and US 2019/0136981 A1.

Proceeding from this, it is the object of the invention to provide a valve arrangement which, in particular when used with a fuel cell, meets the high requirements and which is particularly easy to manufacture.

This object is achieved by the valve arrangement with the features of claim 1. Advantageous configurations are specified in the subsequent dependent claims.

The valve arrangement is provided in particular for a gas line, in particular for a gas line of a fuel cell arrangement and/or a motor vehicle drive arrangement. The valve arrangement has a housing with a fluid line, a valve arranged in the fluid line with a valve seat, a valve flap and a valve opening, the valve flap about a pivot axis between a closed position, in which the valve flap rests on the valve seat and closes the valve opening in a fluid-tight manner. and an open position, in which the valve flap releases the valve opening, can be pivoted, the valve flap in the closed position defining the XY plane of a coordinate system and the pivot axis at a distance from the XY plane is arranged and defines the Y direction of the coordinate system. The valve arrangement is characterized by an alignment mechanism with which the arrangement in which the valve flap is in the closed position relative to the valve seat can be aligned and fixed at least in the X direction.

The fluid line can have a line axis which is arranged essentially in the Z-direction of the coordinate system, ie approximately perpendicular to the plane of the valve flap in the closed position. The valve flap can be pivoted about a pivot axis so that it can pivot back and forth between the closed position and the open position. For this purpose, the valve arrangement can have a swivel drive, in particular with an electric actuator. The swivel drive can be integrated into the housing of the valve arrangement. However, it is also possible to use the valve arrangement without a rotary drive, for example as a check valve.

The valve may have an elastic seal located either on the valve flap or on the valve seat. For this purpose, a separate sealing element can be produced from an elastic material and connected to the valve seat or the valve flap, for example an O-ring can be inserted into a groove running around the valve flap. Such a separate seal is particularly useful if the valve flap or the valve seat is manufactured in a machining process, for example from metal. If the valve seat or the valve flap is produced in an injection molding process, in particular from plastic, the elastic seal can be inserted into the production mold or molded on as a separate part.

The pivot axis of the valve flap is arranged at a distance from the XY plane, ie from the plane of the valve flap in the closed position. It is therefore “outside the valve flap” and is offset from the plane in which the valve seat is arranged. The pivot axis can in particular also be offset in the X-direction relative to the line axis. This arrangement of the pivot axis is of Known butterfly valves and is also referred to as double staggered arrangement.

In the invention, the valve arrangement has an alignment mechanism with which the arrangement in which the valve flap is in the closed position relative to the valve seat can be aligned and fixed at least in the X direction. In known valve arrangements, the alignment of the valve flap in the X-direction is predetermined by the pivot axis and cannot be adjusted. This makes it necessary to keep the tolerances that are unavoidable during production and assembly small and/or to compensate for them with generously dimensioned, elastic seals. With the invention it is instead possible to align the arrangement of the valve flap in the closed position in order to compensate for the unavoidable tolerances and then to fix the valve flap in this aligned position. As a result, a very good seal can be achieved without causing greater actuating forces and greater wear.

In one embodiment, the arrangement in which the valve flap is in the closed position relative to the valve seat can also be aligned and fixed in the Y-direction with the alignment mechanism. A fine adjustment is thus also possible in the direction of the pivot axis with the aid of the alignment mechanism.

In one embodiment, the arrangement in which the valve flap is in the closed position relative to the valve seat can also be aligned and fixed in the Z direction with the alignment mechanism. This additional alignment option not only allows the position of the valve flap to be adjusted in the valve plane, but also in the direction of the line axis. In particular, this makes it possible to influence the contact pressure on an elastic seal that is arranged between the valve seat and the valve flap.

In one embodiment, the valve has a shaft for pivoting the valve flap, with the alignment mechanism relating to the attachment of the valve flap to the shaft. The shaft can in particular be connected to an actuator which is arranged outside the line and for example in the housing. In the butterfly valves known from the prior art, the valve flap is firmly connected to the shaft without the possibility of fine adjustment, in particular by being pressed on. In the invention, an alignment mechanism acting between the shaft and the valve flap is provided, with which the arrangement of the valve flap relative to the shaft can be adjusted. In this way, the arrangement of the valve flap can be easily adjusted without requiring structural changes on the part of the actuator or the bearing of the shaft.

In one embodiment, the alignment mechanism has a screw attachment of the valve flap to the shaft. In this way the location of the butterfly valve relative to the shaft can easily be adjusted prior to tightening the bolts.

In one embodiment, the shaft has at least one through hole in which a screw of the screw attachment is arranged, and a flat, first stop surface which surrounds the through hole on a side of the shaft facing the valve flap and which is clamped to the valve flap by the screw attachment. In this way, the valve flap can be easily and securely attached to the shaft. With the first stop surface of the shaft, the arrangement of the valve flap in the Z direction (in the closed position) can be firmly specified, but there is the desired alignment option in the plane of the valve flap (X and/or Y direction).

In one embodiment, the outer diameter of the screw is smaller than a cross-sectional dimension of the through hole to allow alignment in the XY plane. The screw is therefore not fitted exactly into the through hole, but is subject to play due to the above-mentioned matching of the outer diameter of the screw to the cross-sectional dimension of the through hole, so that the arrangement of the valve flap in the XY plane is only fixed when the screw is tightened. The through hole can be circular in cross section, in which case the Cross-sectional dimension the inner diameter of the through hole. However, the through-hole can also have an elongate, elliptical or other cross-sectional geometry, in particular it can be designed as an elongated hole. In this case, the cross-sectional dimension corresponds to a maximum opening width of the through hole. In particular, the outer diameter of the screw can be at least 2%, at least 10% or at least 15% smaller than the cross-sectional dimension of the through hole. The resulting play is sufficient for the desired alignment. A lower limit for the outer diameter of the screw is given by the strength requirements. For example, it may be at least 10% or at least 20% of the cross-sectional dimension of the through hole.

In one embodiment, the shaft has a second stop surface on a side facing away from the valve flap, which is arranged plane-parallel to the first stop surface and on which a head of the screw is supported. It goes without saying that the head of the screw does not have to be in direct contact with the second stop surface for this purpose, but that a washer, for example, can be arranged in between if necessary. Due to the two plane-parallel stop surfaces, the unit formed by the valve flap and the screw can be displaced overall in the X-Y plane along the plane-parallel stop surfaces until the desired alignment is achieved.

In one embodiment, a blind hole with a thread, into which the screw is screwed, is formed on the valve flap. This solution ensures that the valve flap is not leaked by the alignment mechanism. In addition, the valve flap can be smooth and/or flat on the side facing away from the pivot axis, which can be advantageous in terms of flow technology, particularly in the open position.

In one embodiment, the shaft has two through holes, which are arranged on both sides of a central axis of the line and in each of which a screw is arranged. In particular, the two abutment surfaces mentioned can be made so large that they both have through-holes include, in other words, a central portion of the shaft is flattened from both sides. This also has advantages in terms of flow technology and can simplify production and the desired alignment of the valve flap relative to the shaft.

In one embodiment, the alignment mechanism includes an adhesive or welded attachment of the valve flap to the shaft. In this case, the valve flap can be aligned in the desired manner before the assembly of the valve arrangement and fixed by subsequent welding or curing of the adhesive bond. The welding attachment can in particular be carried out by laser welding, in particular in connection with a valve flap and a shaft made of a thermoplastic material.

In one embodiment, the shaft has a through hole into which a pin formed on the valve flap is inserted, with an annular gap being formed between the pin and the through hole, which allows the valve flap to be aligned when the valve assembly is installed and which when the valve assembly is fastened Valve flap on the shaft is at least partially closed by gluing or welding. The described alignment of the valve flap in the XY plane is possible through the annular gap. The length of the pin and the through-hole can be matched to one another in such a way that the desired attachment is also successful after adjustment in the Z-direction.

The object specified above is also achieved by the fuel cell arrangement with the features of claim 13. The fuel cell arrangement is intended in particular for a motor vehicle drive and has at least one fuel cell and a gas line for supplying and/or discharging gas to or from the at least one fuel cell. The fuel cell arrangement has a valve arrangement according to one of Claims 1 to 12 for blocking the gas line by moving the valve flap into the closed position. The fuel cell can in particular be a hydrogen fuel cell. The object specified above is also achieved by the motor vehicle with the features of claim 14. The motor vehicle has a line and a valve arrangement according to one of claims 1 to 12 for blocking the line by moving the valve flap into the closed position, the line in particular being a gas line a motor vehicle drive and/or a fuel cell arrangement of the motor vehicle.

The invention is explained in more detail below with reference to exemplary embodiments illustrated in figures. Show it:

Figure 1 shows a valve assembly in a perspective view,

FIG. 2 shows the valve arrangement from FIG. 1 in a further perspective representation, partly in section,

FIG. 3 shows the valve arrangement from FIG. 1 in a sectional view,

FIG. 4 shows the valve arrangement from FIG. 1 in a further sectional view,

Figure 5 shows another valve assembly in a sectional view, and

FIG. 6 shows another valve arrangement, also in a sectional view.

The valve arrangement from FIG. 1 has a housing 10 through which a fluid line 12 is formed. The fluid line 12 has a circular cross-section. Facing the viewer is a flange 14 of the housing 10, via which the valve arrangement can be connected to a further piece of line. A valve flap 16 is shown in FIG. 1, as well as in all other figures, in its closed position. The valve flap 16 bears with its outer, circular edge against an elastic seal 18 which forms a valve seat. The valve flap 16 is disc-shaped. In the closed position shown, it is arranged orthogonally to a line axis 20 (see FIG. 2) of the fluid line 12 and defines an XY plane of a coordinate system 22 that is used for the further description of the respective directions. Line axis 20 is a central longitudinal axis of fluid line 12 in the area of valve flap 16.

A shaft 24 of the valve, which defines a pivot axis of the valve flap 16, runs parallel to the Y axis of this coordinate system 22 . The shaft 24 runs transversely through the fluid line 12 and is connected to an electrical actuator 26 of the valve arrangement which is flanged to the housing 10 . The electric actuator 26 serves as an actuating drive for the valve and can move the valve flap 16 back and forth between the closed position shown and an open position (not shown) by rotating the shaft 24 .

The alignment mechanism for aligning and fixing the valve flap 16 relative to the valve seat is implemented in the exemplary embodiment in FIGS. 1 to 4 and in the exemplary embodiment in FIG. It can be seen in FIG. 1 that the shaft 24 has two plane-parallel stop surfaces in a middle section. A first, flat stop surface 28 is located in FIG. 1 on the side of the shaft 24 facing away from the viewer. A second, flat stop surface 30 faces the viewer. At a distance on both sides of the line axis and within the two stop surfaces 20, 30, the shaft 24 has two through holes 32 (see FIG. 3), through each of which a screw 34 is passed.

On the side of the valve flap 16 facing the viewer in Figure 1, which also faces the shaft 24 and its first stop surface 28, the valve flap 16 has two dome-like projections 36, in each of which a blind hole 38 (see Figure 3) with a thread is formed, in each of which one of the screws 34 is screwed. In this way, the valve flap 16 is braced against the first stop face 28 . The inner diameter of the through holes 32 is larger than the outer diameter of the screws 34, so that the screw connection has play in the X-direction and in the Y-direction. Therefore, when assembling the valve assembly, prior to tightening the screws 34, the valve flapper 16 can be aligned in the XY plane and matched to the valve seat. The screws 34 are then tightened, thereby fixing the arrangement of the valve flap 16 relative to the valve seat.

The line axis 20 of the fluid line 12 is shown in FIG. It can be seen that it runs along the Z-direction of the coordinate system 22 that is also shown. The flattened cross section of the shaft in the central longitudinal section with the two stop surfaces 28, 30 is also clearly visible. The complex cross-sectional geometry of the circumferential, elastic seal 18 is also clearly visible, and that this seal 18 fits into the circular opening of the housing 10, which Fluid line 12 forms, is used. The shaft 24 extends along the pivot axis of the valve flap 16. The pivot axis is located at a distance from the plane of the valve flap 16.

In the sectional representation of FIG. 3, the sectional plane runs parallel to the X-Z plane. The essential elements of the alignment mechanism can be clearly seen in FIG. It can be seen that the inside diameters of the two through holes 32 are significantly larger than the outside diameters of the screws 34, so that the valve flap 16 can be aligned relative to the valve seat in the X-Y plane. It is also clearly evident that the valve flap 16 is clamped to the first stop surface 28 via the screws 34 and that the heads of the screws 34 bear against the second stop surface 30 . The shaft 24 is rotatably mounted in the housing 10 and connected to the electric actuator 26 (only indicated in outline on the right in FIG. 3).

FIG. 4 shows the arrangement from FIGS. 1 to 3 again in a different sectional plane. This time, the sectional plane runs parallel to the XZ plane of the coordinate system 22. It can be seen that the shaft 24 and thus the pivot axis of the valve flap 16 is arranged perpendicular to the line axis 20 of the fluid line 12 and laterally (in the X direction) offset thereto. In the further exemplary embodiment of FIG. 5, only a few elements of another valve arrangement are shown in section. It can be seen that the valve flap 16 has a circumferential groove 40 into which an O-ring is inserted as an elastic seal 18 . This seals against valve seat 42 . A screw connection with a screw 34 which is inserted through a through hole 32 in a shaft 24 with play is also used as the alignment mechanism. The screw 34 is screwed into a threaded blind hole 38 which is formed in a dome-like extension 36 on the valve flap 16 . In this exemplary embodiment, too, the shaft 24 has a flat stop surface 28 on the side facing the valve flap 16, with which the valve flap 16 is clamped via the screw 34, and a second stop surface 30, aligned plane-parallel to the first stop surface 28, on which the Head of the screw 34 rests.

FIG. 6 also shows only selected elements of another valve arrangement in a sectional view. The valve flap 16 is provided with a circumferential groove 40, similar to that of FIG. 5, into which an elastic seal 18 in the form of an O-ring is inserted. However, another alignment mechanism is provided that does not have a screw connection. Instead of the screw connection, a pin 44 is formed on the valve flap 16 and is guided into a through hole 32 in the shaft 24 . The diameter of the through hole 32 is selected to be larger than the outer diameter of the pin 44, so that this arrangement is initially subject to play to the extent that an alignment of the valve flap 16 relative to the valve seat 42 is possible, specifically in X, Y, and Z Direction. After the desired alignment has been found, a permanent connection between the journal 44 and the shaft 24 is produced by laser welding, the annular gap formed between the journal 44 and the through-hole 32 being completely or partially closed.

Claims

patent claims

1. Valve arrangement, in particular for a gas line, in particular for a gas line of a fuel cell arrangement and/or a motor vehicle drive arrangement, the valve arrangement having a housing (10) with a fluid line (12), a valve arranged in the fluid line (12) and having a valve seat (42 ), a valve flap (16) and a valve opening, the valve flap (16) pivoting about a pivot axis between a closed position, in which the valve flap (16) bears against the valve seat (42) and closes the valve opening in a fluid-tight manner, and an open position, in which the valve flap (16) releases the valve opening, can be pivoted, the valve flap (16) in the closed position defining the X-Y plane of a coordinate system (22) and the pivot axis being arranged at a distance from the X-Y plane and the Y direction of the coordinate system (22), characterized by an alignment mechanism with which the arrangement in which the valve flap (16) is in d it is in the closed position relative to the valve seat (42), can be aligned and fixed at least in the X direction.

2. Valve arrangement according to claim 1, characterized in that the arrangement in which the valve flap (16) is in the closed position relative to the valve seat (42) can also be aligned and fixed in the Y-direction with the alignment mechanism.

3. Valve arrangement according to claim 1 or 2, characterized in that the arrangement in which the valve flap (16) is in the closed position relative to the valve seat (42) can also be aligned and fixed in the Z-direction with the alignment mechanism.

4. Valve arrangement according to one of claims 1 to 3, characterized in that the valve has a shaft (24) for pivoting the valve flap (16), the alignment mechanism relating to the attachment of the valve flap (16) to the shaft (24).

5. Valve arrangement according to claim 4, characterized in that the alignment mechanism comprises a screw attachment of the valve flap (16) to the shaft (24).

6. Valve arrangement according to Claim 4 or 5, characterized in that the shaft (24) has at least one through hole (32), in which a screw (34) of the screw fastening is arranged, and a flat, first stop surface (28) which Surrounds through hole (32) on one of the valve flap (16) facing side of the shaft (24) and is braced by the screw fastening with the valve flap (16).

The valve assembly of claim 6, characterized in that the outer diameter of the screw (24) is smaller than a cross-sectional dimension of the through hole (32) to allow alignment in the X-Y plane.

8. Valve arrangement according to claim 7, characterized in that the shaft (24) has a second stop surface (30) on a side facing away from the valve flap (16) which is arranged plane-parallel to the first stop surface (28) and on which a head of the screw (34) is supported.

9. Valve arrangement according to one of claims 6 to 8, characterized in that on the valve flap (16) a blind hole (38) is formed with a thread into which the screw (34) is screwed.

10. Valve arrangement according to one of claims 5 to 8, characterized in that the shaft (24) has two through holes (32) which are arranged on both sides of a line axis (20) of the fluid line (12) and in each of which a screw ( 34) is arranged.

11. Valve arrangement according to one of claims 1 to 3, characterized in that the alignment mechanism has an adhesive or welded attachment of the valve flap (16) to the shaft (24).

12. Valve arrangement according to claim 11, characterized in that the shaft (24) has a through hole (32) into which a pin (44) formed on the valve flap (16) is inserted, with between the pin (44) and the through hole (32) an annular gap is formed which enables the valve flap (16) to be aligned during assembly of the valve arrangement and which is at least partially closed by gluing or welding when the valve flap (16) is fastened to the shaft (24).

13. Fuel cell arrangement, in particular for a motor vehicle drive, with at least one fuel cell and a gas line for supplying and/or discharging gas to or from the at least one fuel cell, and a valve arrangement according to one of claims 1 to 12 for blocking the gas line through Adjusting the valve flap (16) to the closed position.

14. Motor vehicle with a line and a valve assembly according to one of claims 1 to 12 for blocking the line by adjusting the valve flap in the closed position, wherein the line is in particular a gas line of a motor vehicle drive and / or a fuel cell assembly of the motor vehicle.