DE102024206207A1 - Non-return valve device for a withdrawal path of a tank valve unit and tank valve unit for a gas tank system - Google Patents

Abstract

The invention relates to a check valve device (10) for a withdrawal path of a tank valve unit (1), in particular a hydrogen tank valve, and a tank valve unit (1). The check valve device (10) is equipped with: a valve housing (11); a flow opening (12) within the valve housing (11); and a bending spring device (13) having a fixed end section (13a) that is fixed to the valve housing (11) and a loose end section (13b) that is elastically deformable, wherein the bending spring device (13) closes the flow opening (12) in a closed position (GS).

Description

The present invention relates to a check valve device for a withdrawal path of a tank valve unit, in particular a hydrogen tank valve, and to a tank valve unit with such a check valve device.

State of the art

Climate-neutral hydrogen, as an environmentally friendly energy carrier for fuel cells and combustion engines as a drive system for mobile and stationary applications, is becoming increasingly important. High-pressure gas cylinders are used for storing the hydrogen. These cylinders are typically fitted with so-called "multifunctional tank valves," which control both refueling and dispensing for the consumer.

Tank valve units are known from the prior art. Typically, the filling path is secured with a check valve, so that fluid can only flow out of the tank via the withdrawal path (when the electric tank valve is open). At high filling rates, the check valve also causes a pressure drop in the flow direction, resulting in excessive pressure on the secondary side of the electric tank valve. This pressure forces the tank valve open, and fluid then flows into the tank via the withdrawal path (unrestricted). This creates high velocities at the seat of the electric tank valve, which can lead to damage, for example, to the elastomer in the seat area. While a check valve in the withdrawal path can prevent this, it creates conditions in the system where the tank valve no longer opens.

Several types of check valves are known in the prior art. For example, the DE 25 21 878 A1 a check valve, the movable valve body of which is guided by a leaf spring and pressed against the valve seat, characterized in that the valve body is held by a substantially flat, annular leaf spring with through-holes, the inner edge of which surrounds the valve body and the outer edge of which is clamped in the parting line of a two-part valve housing.

Disclosure of the invention

The invention provides a check valve device for a withdrawal path of a tank valve unit, in particular a hydrogen tank valve, with the features of claim 1, and a tank valve unit for a gas tank system with the features of claim 10.

According to a first aspect of the invention, a check valve device is provided for a withdrawal path of a tank valve unit, in particular a hydrogen tank valve. The check valve device comprises a valve housing and a flow opening within the valve housing. Furthermore, the check valve device comprises a bending spring device having a fixed end section and a loose end section. The fixed end section is fixed to the valve housing. The loose end section is elastically deformable. The bending spring device closes or covers the flow opening in a closed position.

According to a second aspect of the invention, a tank valve unit for a gas tank system is provided. The tank valve unit comprises a check valve device according to the first aspect of the invention.

One of the underlying ideas of the present invention is to equip the check valve device with features to provide slow pressure equalization while simultaneously ensuring good sealing against the direction of discharge of the check valve device. In this case, the spring constant of the bending spring device can be chosen to be low, since the bending spring device does not need to, and indeed should not, seal.

In the closed position, the bending spring device covers the flow opening in such a way that it does not completely seal it. In this way, flow against the direction of flow from the check valve can be essentially blocked, while ensuring slow pressure equalization. For example, the bending spring device may rest unevenly against one edge of the flow opening. This edge can then form a valve seat.

The check valve device can open when an overpressure, i.e. an opening pressure, between the tank valve unit and a storage bottle, or the static pressure difference immediately before and after the check valve device, which is caused by flow and absolute pressure losses, is at least in equilibrium with the correspondingly adjusted spring force setting.

In the open position of the check valve, a fluid flows through the check valve, particularly through the flow orifice. The fluid, for example hydrogen, flows through a gap between the edge of the flow opening and the bending spring device raised from the edge. In the open position, sufficient cross-section is exposed to allow extraction from the gas tank system. The gas tank system can be designed as a pressure vessel for storing hydrogen.

An advantage of the present invention is that there are no constrictions in the extraction direction, i.e., the main flow direction. Therefore, the check valve device according to the invention can be insensitive to contamination.

Advantageous designs and further developments result from the further sub-claims as well as from the description with reference to the figures in the drawing.

According to a further development of the invention, the bending spring device is designed as a leaf spring. The leaf spring can be manufactured and assembled simply and cost-effectively. A check valve device equipped with the leaf spring can also be referred to as a reed valve.

According to a further embodiment of the invention, the bending spring device is made of spring steel or plastic. This ensures elastic deformability and load-bearing capacity. For example, the spring steel can be stainless steel. Stainless steel is particularly suitable for hydrogen-related applications. Plastic can be used especially for lower loads on the bending spring device. The type of plastic can be selected according to the specific load requirements.

According to a further embodiment of the invention, the bending spring device has a predetermined surface roughness or exceeds it in a contact area between the bending spring device and the valve housing. Thus, the predetermined surface roughness can correspond to a targeted minimum roughness.

According to a further embodiment of the invention, the valve housing comprises a first housing shell and a second housing shell, which together form the valve housing. In this way, the bending spring assembly can be easily fixed. In particular, the bending spring assembly can be fixed to the first or the second housing shell, or clamped or clamped between the first and second housing shells. For example, the valve housing can consist of the first and second housing shells. The flow opening can be formed by the second housing shell or by both the first and second housing shells. Alternatively, the valve housing can be formed in one piece.

According to a further embodiment of the invention, the second housing shell engages with the first housing shell. This allows for improved assembly. For example, the first housing shell can have two projections between which the second housing shell is embedded. These two projections can correspond to end faces of the second housing shell.

According to a further embodiment of the invention, the first housing shell and the second housing shell are connected to each other in a form-fitting manner, in particular by screws, or by a force-fitting manner, in particular by pressing together, or by a material-fitting manner, in particular by welding.

According to a further embodiment of the invention, the bending spring device has a recess for the flow of a fluid. This allows for the precise provision of a small flow rate in the closed position. In other words, the recess allows for more precise control of leakage in the closed position. For example, the recess can be created in the bending spring device by drilling, electrical discharge machining (EDM), or a comparable manufacturing process. The recess can, for example, be located in the area of the flow opening.

According to a further embodiment of the invention, the valve housing has a stop element for limiting the direction of movement of the bending spring assembly. The stop element can, for example, be arranged in relation to the bending spring assembly in such a way as to prevent excessive opening of the bending spring assembly. Thus, movement of the bending spring assembly in the direction of the open position can be limited.

Alternatively or additionally, the stop element can, for example, be arranged in relation to the bending spring device in such a way that it prevents the bending spring device from swinging beyond the closed position. This limits the movement of the bending spring device towards the closed position. The stop element for preventing the bending spring device from swinging can be located in the area of the center of the flow opening.

The stop element can be designed as a projection that extends from an inner wall of the first or second housing shell.

Optionally, the valve housing can have a round, for example circular, cross-section. The round cross-section can facilitate a force-fit connection, in particular a press fit, of the check valve device into a pipe or bore, for example, the extraction path.

Brief description of the drawings

• 1 eine schematische Blockdarstellung eines Ausschnitts einer Tankventileinheit für ein Gastanksystem gemäß einem Ausführungsbeispiel der Erfindung;
• 2 eine schematische Schnittansicht einer Rückschlagventilvorrichtung für einen Entnahmepfad einer Tankventileinheit, insbesondere eines Wasserstofftankventils, gemäß einem Ausführungsbeispiel der Erfindung; und
• 3 eine schematische Schnittansicht einer Rückschlagventilvorrichtung für einen Entnahmepfad einer Tankventileinheit, insbesondere eines Wasserstofftankventils, gemäß einem weiteren Ausführungsbeispiel der Erfindung.

The invention will now be explained with reference to the figures in the drawings. The figures show:

• 1 a schematic block representation of a section of a tank valve unit for a gas tank system according to an embodiment of the invention;
• 2 a schematic sectional view of a check valve device for a withdrawal path of a tank valve unit, in particular a hydrogen tank valve, according to an embodiment of the invention; and
• 3 a schematic sectional view of a check valve device for a withdrawal path of a tank valve unit, in particular a hydrogen tank valve, according to a further embodiment of the invention.

In the figures, the same reference symbols denote identical or functionally equivalent components, unless otherwise stated. The numbering of process steps is for clarity and generally does not imply a specific chronological order. In particular, several process steps can be performed simultaneously.

Description of the exemplary implementations

Further advantages, features and details of the invention will become apparent from the following description, in which various embodiments are described in detail with reference to the drawing.

1 Figure 1 shows a schematic block representation of a section of a tank valve unit 1 for a gas tank system according to an embodiment of the invention.

The tank valve unit 1 includes, for example, a check valve device 10 for a withdrawal path E of the tank valve unit 1. Furthermore, a filling path B is also secured with a check valve, so that fluid can flow out via the withdrawal path E when the tank valve unit 1 is open. The tank valve unit 1 can be electrically controlled.

The check valve device 10 comprises a valve housing and a flow opening within the valve housing. Furthermore, the check valve device 10 comprises a bending spring assembly having a fixed end section that is fixed to the valve housing and a loose end section that is elastically deformable. The bending spring assembly closes or covers the flow opening in a closed position.

2 Figure 1 shows a schematic sectional view of a check valve device 10 for a withdrawal path E of a tank valve unit 1, in particular a hydrogen tank valve, according to an embodiment of the invention. Specifically, the following are shown in Figure 1: 2 A schematic sectional view from the side and a schematic sectional view AA from the front are shown.

The illustrated check valve device 10 includes a valve housing 11, a flow opening 12 inside the valve housing 11 and a bending spring device 13.

The bending spring device 13 has a fixed end section 13a and a loose end section 13b. The fixed end section 13a is fixed to the valve housing 11, and the loose end section 13b is elastically deformable. The bending spring device 13 closes or covers the flow opening 12 in a closed position GS. In the closed position GS, the bending spring device 13 closes or covers the flow opening 12 in such a way that it does not completely seal the flow opening 12. In this way, flow against a withdrawal direction of the check valve device 1 can be substantially blocked, while ensuring slow pressure equalization. For example, the bending spring device 13 can bear unevenly against one edge of the flow opening.

For example, the valve housing 11 can have a first housing shell 11a and a second housing shell 11b, which together form the valve housing 11, as shown by way of example in 2 This is illustrated. In this way, the bending spring device 13 can be easily fixed. For example, the bending spring device 13 can be fixed to the second housing shell 11b or clamped or clamped between the first housing shell 11a and the second housing shell 11b.

The flow opening 12 can be formed by the second housing shell 11b, but is not limited to this. Alternatively, the valve housing 11 can be formed in one piece.

Furthermore, the first housing shell 11a and the second housing shell 11b can be connected to each other in a form-fitting manner, in particular by screws, or by a force-fitting manner, in particular by pressing together, or by a material-fitting manner, in particular by welding.

Here, the bending spring device 13 is designed as a leaf spring by way of example. A check valve device equipped with a leaf spring can also be called a reed valve. Furthermore, the bending spring device 13 can be made of spring steel or plastic. For example, the spring steel can be stainless steel. Stainless steel is particularly suitable for applications involving hydrogen. Plastic can be used especially for lower loads on the bending spring device 13. The type of plastic can be selected according to the loads.

Optionally, the bending spring device 13 can have or exceed a predetermined surface roughness in a contact area between the bending spring device 13 and the valve housing 11. Thus, the predetermined surface roughness can correspond to a specific minimum roughness.

Furthermore, the bending spring device 13 can have a recess (not shown) for the flow of a fluid. In this way, a small flow rate can be precisely provided in the closed position. In other words, leakage in the closed position can be more accurately controlled by means of the recess. For example, the recess can be created in the bending spring device 13 by drilling, electrical discharge machining (EDM), or a similar manufacturing process. The recess can, for example, be located in the area of the flow opening 12.

Optionally, the valve housing 11 can have a round cross-section, as shown in particular in sectional view A-A. For example, the valve housing 11 can be cylindrical. The round cross-section can facilitate a force-fit connection, in particular a press-fit, of the check valve device 1 into a pipe or bore, for example, the extraction path E.

3 Figure 1 shows a schematic sectional view of a check valve device 10 for a withdrawal path E of a tank valve unit 1, in particular a hydrogen tank valve, according to a further embodiment of the invention. Specifically, in 3 A schematic sectional view from the side and a schematic sectional view BB from the front are shown.

The check valve device 1 illustrated here has essentially the same features as the check valve device 1 from 2 Furthermore, the second housing shell 11b engages with the first housing shell 11a, for example. The first housing shell 11a can have two projections between which the second housing shell 11b is embedded. These two projections can correspond to end faces of the second housing shell 11b, as is shown in particular in the side sectional view.

Furthermore, the valve housing 11 here has a stop element 14 for limiting one direction of movement of the bending spring device 13. The stop element 14 can, for example, be arranged in relation to the bending spring device 13 such that excessive opening of the bending spring device 13 is prevented. Thus, movement of the bending spring device 13 in the direction of the open position can be limited. The open position is in 3 The illustration is provided by way of example, showing the bending spring device 13 in contact with the stop element 14. The stop element 14, which prevents excessive opening of the bending spring device 13, can, for example, be designed as a projection and protrude from an inner wall of the first housing shell 11a.

Alternatively or additionally, the stop element 14 can, for example, be arranged in relation to the bending spring device 13 such that it prevents the bending spring device 13 from swinging beyond the closed position GS. This limits the movement of the bending spring device 13 in the direction of the closed position GS. The stop element 14 for preventing the bending spring device from swinging can be located in the area of the center of the flow opening 12. The stop element 14 for preventing the bending spring device 13 from swinging can be designed as a projection extending from an inner wall of the second housing shell 11b.

Although the present invention has been explained above by way of example embodiments, it is not limited to these, but can be modified in many ways. In particular, combinations of the preceding embodiments are also conceivable.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• DE 25 21 878 A1 [0004]

Claims (10)

Check valve device (10) for a withdrawal path (E) of a tank valve unit (1), in particular a hydrogen tank valve, comprising: a valve housing (11); a flow opening (12) within the valve housing (11); and a bending spring device (13) comprising a fixed end region (13a) which is fixed to the valve housing (11) and a loose end region (13b) which is elastically deformable, wherein the bending spring device (13) closes the flow opening (12) in a closed position (GS). Check valve device (10) after Claim 1 , wherein the bending spring device (13) is designed as a leaf spring. Check valve device (10) after Claim 1 or 2 , wherein the bending spring device (13) is made of spring steel or plastic. Check valve device (10) according to one of the preceding claims, wherein the bending spring device (13) has or exceeds a predetermined surface roughness in a contact area between the bending spring device (13) and the valve housing (11). Check valve device (10) according to one of the preceding claims, wherein the valve housing (11) has a first housing shell (11a) and a second housing shell (11b) which together form the valve housing (11). Check valve device (10) after Claim 5 , wherein the second housing shell (11b) engages with the first housing shell (11a). Check valve device (10) after Claim 5 or 6 , wherein the first housing shell (11a) and the second housing shell (11b) are connected to each other in a form-fitting manner, in particular by screws, or by a force-fitting manner, in particular by pressing together, or by a material-fitting manner, in particular by welding. Check valve device (10) according to one of the preceding claims, wherein the bending spring device (13) has a recess for the flow of a fluid. Check valve device (10) according to one of the preceding claims, wherein the valve housing (11) has a stop element (14) for limiting a direction of movement of the bending spring device (13). Tank valve unit (1) for a gas tank system, with a check valve device (10) according to one of the preceding claims.