RAIL FOR A HYDROGEN PRESSURE TANK SYSTEM AS AN EXTRACTED PROFILE COMPONENT

Description

[0001] The present invention relates to a so-called rail for connecting several hydrogen pressure tanks in a hydrogen pressure tank system and to a hydrogen pressure tank system with such a rail. State of the art

[0002] Vehicles with a fuel cell system may be equipped with a pressure tank system for hydrogen supply. This system can consist of several pressure vessels hydraulically connected via a common rail. According to current technology, the individual cylinders are connected to the rail by screwing them onto individual threaded fittings integrated into the rail. Alternatively, the individual cylinders can be pressure-tightly fixed to the rail using connecting sleeves and various fastening methods.

[0003] Rails typically have concentric, tubular cross-sections. A central hole can be drilled from one or both ends. Due to the often greater length of the rail, there is a risk that the drill bit used for drilling will not run straight, resulting in an eccentric hole in the rail, or that the holes will not align precisely when drilling from both ends. This could lead to inhomogeneous stress distributions under applied pressure and / or localized pressure peaks, potentially causing component failure.

[0004] WO 2021 / 220128 A1 discloses a rail for connecting multiple hydrogen pressure tanks in a hydrogen pressure tank system.

[0005] DE 10 2014 016962 A1 discloses a device for storing gases with several pressure gas containers, each with at least one separate valve device and a common filling nozzle.

[0006] From US 2014 / 130896 A1, a pressure storage arrangement with at least two pressure vessels is known, wherein the at least two pressure vessels are designed to be connected to each other in a fluid-conducting manner via a connecting device.

[0007] FR 2 905 446 A1 discloses a device for coupling small cartridge-like gas containers and in particular a screw valve cartridge.

[0008] US 6 708 719 B2 discloses a fastening structure for a variety of high-pressure gas containers, wherein the fastening structure features a block-shaped container fastening element with high rigidity. Disclosure of the invention

[0009] It is an object of the invention to propose a rail for a pressure tank system or a pressure tank system with a rail, wherein the rail has a voltage distribution that is as homogeneous as possible and as few local pressure peaks as possible.

[0010] The invention relates to a hydrogen pressure tank system comprising several hydrogen pressure tanks and a rail as described above, wherein the hydrogen pressure tanks are each connected to a connection channel of the rail via an individual connection element, so that they are in fluid communication with the at least one longitudinal channel. For example, the hydrogen pressure tank system can be used in a fuel cell vehicle.

[0011] The problem is solved by a hydrogen pressure tank system with a rail having the features of independent claim 1. Advantageous embodiments and further developments can be found in the dependent claims and the following description.

[0012] A hydrogen pressure tank system is proposed, comprising a rail for connecting multiple hydrogen pressure tanks in a hydrogen pressure tank system, comprising a first end face, a second end face arranged opposite the first end face, and at least one longitudinal channel extending from the first end face to the second end face, wherein the rail is designed as an extruded profile component with a constant cross-section, wherein the at least one longitudinal channel is formed as at least one recess in the cross-section, wherein the cross-section preferably has at least one axial or point symmetry, and wherein at least one connection channel extends transversely from a side surface running between the end faces into the at least one longitudinal channel and is connectable to a connection element for connecting a hydrogen pressure tank.However, in the aforementioned sense, it is also conceivable that the cross-section is polygonal, in particular polygonal.

[0013] The hydrogen pressure tank system with a rail is preferably an elongated component whose length is adapted to the number of hydrogen pressure tanks to be connected to the rail. The rail is bounded by two opposing end faces. At least one longitudinal channel extends from the first end face to the second end face, i.e., over the entire length of the rail. The longitudinal channel serves as a connecting element for several hydrogen pressure tanks. Each of these tanks can be connected to the at least one longitudinal channel via a corresponding connecting channel. This means that the corresponding connecting channel extends radially from a side face into the at least one longitudinal channel. Consequently, an axis of extension of the at least one longitudinal channel and an axis of extension of the corresponding connecting channel intersect to connect these two channels.

[0014] A particular advantage lies in the fact that the rail is designed as an extruded profile. This allows for virtually any rail length to be achieved while maintaining a consistent cross-section along its entire length. Drilling holes along a longitudinal axis, i.e., along a line connecting the two end faces, is unnecessary. Consequently, manufacturing costs are significantly reduced and precision is increased. Furthermore, the use of extruded profiles also enables the creation of more complex cross-sections. As will be shown below, multiple longitudinal channels with partially differing flow cross-sections can be arranged side by side, serving various purposes.

[0015] The preferably point or axis symmetry allows for the optimization of mechanical stress distribution within the rail. Asymmetric loads can be prevented, which are particularly important at high gas pressures of up to approximately 700 bar and widely fluctuating temperatures, as these can lead to rail deformation in unfavorable conditions.

[0016] Furthermore, it is conceivable to use standardized, extruded profiles for specific applications, thus further reducing manufacturing costs through the use of standard components. Suitable plugs or other closures could be used to prevent hydrogen from escaping at the ends of the rail. It is also conceivable to weld the corresponding openings of the longitudinal channels at the ends. In addition, it is conceivable to provide inlet and outlet connections at the ends, allowing hydrogen to be introduced into or extracted from the hydrogen pressure tank system.

[0017] The hydrogen pressure tank system with a rail could have at least two parallel longitudinal channels spaced apart in cross-section. Using two longitudinal channels would create redundancy. When integrating multiple hydrogen pressure tanks into a single system, it would be conceivable to divide the tanks into two groups, with the tanks of one group connected to one of the longitudinal channels and the tanks of the other group connected to the other. In the event of a mechanical failure of the rail, this would increase the likelihood that at least one group of tanks would still maintain a sufficiently tight connection to a hydrogen consumer via the rail.Should one of the two longitudinal channels have a leak, the associated pressure tanks could be closed, for example via valves individually arranged on the pressure tanks.

[0018] The hydrogen pressure tank system with a single rail could further comprise at least two parallel longitudinal channels with identical diameters or flow areas. The identical diameters ensure identical flow conditions in both rails, i.e., identical coefficients of friction and the like. If the two longitudinal channels are used to create redundancy, it is particularly advantageous that the same flow conditions prevail in both channels.

[0019] The hydrogen pressure tank system with a rail could further comprise at least two parallel longitudinal channels with different diameters or flow areas. The different diameters could be assigned different functions. For example, a longitudinal channel with a larger diameter is conceivable for handling higher volume flows. This could particularly apply to the refueling process, where a corresponding refueling connection is linked to this longitudinal channel to enable relatively rapid filling of the pressure tanks. In conventional operation of the hydrogen pressure tank system, however, the relevant pressure tanks can discharge the hydrogen via a longitudinal channel with a smaller cross-section. This design can not only accelerate refueling but also reduce any residual volume within the rail after the pressure tanks are closed.

[0020] It could be provided that a connection channel opens into each of two diametrically opposed sections of the rail's side surfaces, each of which is connected to one of the at least one longitudinal channel. This could mean that the at least one connection channel extends transversely through the rail and has a connection element at each of its two opposite ends for connecting a hydrogen pressure tank. However, it could also be provided that two separate connection channels open into one of two adjacent longitudinal channels and do not intersect or overlap. Overall, this allows twice the number of pressure tanks to be connected to a rail of limited length compared to pressure tanks arranged only on one side.The connecting channels can be created by drilling two separate blind holes or one through hole, each intersecting the respective longitudinal channel with which a connection is to be made. If the longitudinal channel is located in the center of the trail profile, a diametrically opposed hole could be used.

[0021] The hydrogen pressure tank system with a rail could also feature a ribbed structure on its side surface for heat input or dissipation. During refueling and subsequent pressurization, heat can be generated in the rail, which can be at least partially dissipated by this ribbed structure. However, heat could also be drawn from the environment if a continuous release of hydrogen and the associated expansion result in a low temperature at the connection points, the pressure tanks, and the rail.

[0022] The rail could have at least one first longitudinal channel and at least one second longitudinal channel, wherein the flow cross-section of the at least one second longitudinal channel is larger than the flow cross-section of the at least one first longitudinal channel, and wherein a fluid connection between the hydrogen pressure tanks and the at least one first longitudinal channel as well as the at least one second longitudinal channel is selectively separable. As described above, the larger of the longitudinal channels can be used for refueling, while the smaller longitudinal channel is intended for conventional operation. It is conceivable to provide a switchable valve for switching between a connection to one or the other longitudinal channel.

[0023] The rail could also have at least one third longitudinal channel containing an electrical conductor. Manufacturing longitudinal channels in an extruded profile is very simple, so integrating a cable duct into the rail is also easily possible. An electrical conductor could include not only power lines but also sensor or control lines that are useful for operating the hydrogen pressure tank system.

[0024] The rail could also have at least one fourth longitudinal channel containing a leakage sensor designed to detect hydrogen escaping from another longitudinal channel and entering the fourth longitudinal channel through the rail's cross-section. If the rail ruptures or breaks, hydrogen could enter an adjacent longitudinal channel from one of its longitudinal channels. This adjacent longitudinal channel would preferably remain unused during normal operation of the hydrogen pressure tank system, meaning it would be empty of hydrogen in this state. A sensor could be located in this longitudinal channel to detect the ingress of hydrogen. If hydrogen is detected, this indicates a leak or damage to the rail, allowing for further action, such as shutting off the damaged longitudinal channel.

[0025] Finally, two hydrogen pressure tanks could be arranged on opposite sides, with a retaining clamp establishing a positive-locking contact between them. The clamp spans the rail transversely to the at least one longitudinal channel. The hydrogen pressure tanks could be arranged as mirror images of each other. The retaining clamp could be designed to engage with features of the two pressure tanks. For example, each pressure tank could have a collar or flange that can be brought into surface contact with the retaining clamp.

[0026] Further measures improving the invention are described in more detail below, together with a description of preferred embodiments of the invention, with reference to figures. Examples of implementation

[0027] It shows: Figure 1 a rail with several pressure tanks arranged on one side; Figure 2a rail with several pressure tanks arranged on both sides and enclosing a rail; Figure 3 a partial section view of Figure 2 ; and Figure 4 An isometric partial view of a connection area of ​​two pressure tanks on a rail.

[0028] Fig. 1Figure 1 shows a hydrogen pressure tank system 2 with an elongated rail 4 and several hydrogen pressure tanks 6 connected to the rail 4. The rail 4 is formed as an extruded component and has a first end face 8 and a second end face 10, which define the longitudinal boundaries of the rail 4. Between the first end face 8 and the second end face 10, a longitudinal channel 12, shown here as a dashed line, extends inside the rail 4. A connection channel 14 is provided for each pressure tank 6, extending transversely to the longitudinal channel 12. The connection channel 14 extends through a side surface 16 facing the pressure tanks 6 and is connected to the respective pressure tank 6 via a connection element 18.

[0029] At least one of the end faces 8 and 10 could have a refueling and / or withdrawal connection (not shown). This would allow the hydrogen pressure tank system 2 to be refueled or hydrogen to be supplied to a hydrogen consumer.

[0030] Fig. 2 Figure 1 shows a modified rail 20, which essentially corresponds to rail 4, except that hydrogen pressure tanks 6a and 6b are arranged on both sides of it. For this purpose, connecting channels 14a and 14b extend from a side surface 16 facing the respective pressure tank 6a or 6b into a respective longitudinal channel 14a or 14b of the rail 20, as shown in Figure 2. Fig. 3 shown in more detail. At this point, it should be noted that two converging connection channels 14a and 14b could also be connected to each other to form a common connection channel 14, which could be connected, for example, to a single longitudinal channel 12.

[0031] In Fig. 3Rail 20 is shown in a section view AA, with the section line in Fig. 2 The section is marked. It runs centrally through pressure tanks 6a and 6b. Here it can be seen that the longitudinal channel 12a and the longitudinal channel 12b run parallel to each other and at a distance from one another, with the cross-section of the rail 20 being symmetrical about a vertical axis 21. In this representation, both pressure tanks 6a and 6b are connected to the rail 20 by their respective connecting channels 14a and 14b. Consequently, all pressure tanks 6a on one side of the rail 20 form a first group, while the pressure tanks 6b on the other side of the rail 20 form a second group. Each group has its own longitudinal channel 12a or 12b, thus achieving redundancy.

[0032] The pressure tanks 6a and 6b each have a circumferential, radially projecting collar 22 on one side facing the rail 20. This collar is suitable for attaching a retaining clip 24, as shown in Fig. 4 The retaining clip 24, which is formed from a metallic material, connects two opposing pressure tanks 6a and 6b to the collar 22 by means of a positive fit and spans the rail 20. This holds the pressure tanks 6a and 6b in the intended position with a force acting towards the rail 20. The retaining clip 24 can be spring-loaded so that, in the position shown, it clamps the collars 22 against each other.

[0033] In the cross-section of rail 20, further possible options are shown as examples with dashed lines. Due to their redundant arrangement, longitudinal channels 12a and 12b can be referred to as the first longitudinal channels. A second longitudinal channel 12c with a larger diameter could be provided, for example, for refueling, and could be connected to the pressure tanks 6a and 6b via means not shown here. A third longitudinal channel 12d could be provided to accommodate an electrical line 13, which could be a control or power supply line. A fourth longitudinal channel 12e could be arranged centrally in the cross-section of rail 20 and have a sensor 15 designed to detect hydrogen. If hydrogen escapes from one of the first longitudinal channels 12a and 12b, for example, through a crack or break in rail 20, it could enter the fourth longitudinal channel 12e and be detected there by the sensor 15.Subsequently, a control unit connected to sensor 15 could issue a command to interrupt a hydrogen supply or the like.

Claims

1. Hydrogen pressure tank system (2) having multiple hydrogen pressure tanks (6, 6a, 6b), wherein the hydrogen pressure tanks (6, 6a, 6b) are each connected to a connection channel of a rail (4, 20) via an individual connection element (18), so that they are connected fluidically to the at least one longitudinal channel (12, 12a, 2b), and having the rail (4, 20), wherein the rail (4, 20) has a first end face (8), and wherein the rail (4, 20) has a second end face (10), which is arranged opposite the first end face (8), and wherein the rail (4, 20) has at least one longitudinal channel (12, 12a, 12b, 12c, 12d, 12e) which extends from the first end face (8) to the second end face (10), and wherein the rail (4, 20) is in the form of an extruded profile component with a uniform cross section, and wherein the at least one longitudinal channel (12, 12a, 12b, 12c, 12d, 12e) is in the form of at least one cutout in the cross section, and wherein the cross section has at least line symmetry or point symmetry or a polygonal shape, and wherein at least one connection channel (14, 14a, 14b) extends transversely from a side surface (16), extending between the end faces (8,10), into the at least one longitudinal channel (12, 12a, 12b, 12c, 12d, 12e) and is connectable to a connection element (18) for connection of a hydrogen pressure tank (6, 6a, 6b), characterized in that the rail (4, 20) has at least one third longitudinal channel (12d) with an electrical line (13) arranged therein.

2. Hydrogen pressure tank system (2) according to Claim 1, wherein the rail (4, 20) has at least one first longitudinal channel (12a, 12b) and at least one second longitudinal channel (12c), wherein a flow cross section of the at least one second longitudinal channel (12c) is larger than a flow cross section of the at least one first longitudinal channel (12a), and wherein a fluidic connection between the hydrogen pressure tanks (6, 6a, 6b) and the at least one first longitudinal channel (12a, 12b) and the at least one second longitudinal channel (12c) is selectively disconnectable.

3. Hydrogen pressure tank system (2) according to Claim 1 or 2, wherein the rail (4, 20) has at least one fourth longitudinal channel (12e) in which there is arranged a leakage sensor (15) configured to detect hydrogen which escapes from another longitudinal channel (12a, 12b, 12c, 12d) and which enters the fourth longitudinal channel (12e) by way of the cross section of the rail (4, 20).

4. Hydrogen pressure tank system (2) according to one of Claims 1 to 3, wherein two hydrogen pressure tanks (6, 6a, 6b) are arranged on two mutually opposite sides and a holding bracket (24) establishes a form-fitting contact with both hydrogen pressure tanks (6, 6a, 6b), and wherein the holding bracket (24) spans the rail (4, 20) transversely to the at least one longitudinal channel (12, 12a, 12b, 12c, 12d, 12e).

5. Hydrogen pressure tank system (2) according to Claim 1, wherein the rail (4, 20) has at least two longitudinal channels (12, 12a, 12b, 12c, 12d, 12e) running parallel to one another that are spaced apart from one another in the cross section.

6. Hydrogen pressure tank system (2) according to Claim 1 or 5, wherein the rail (4, 20) has at least two longitudinal channels (12, 12a, 12b, 12c, 12d, 12e) running parallel to one another that have identical diameters or flowed-through areas and / or have mutually different diameters or flowed-through areas.

7. Hydrogen pressure tank system (2) according to Claim 1, 5 or 6, wherein opening out into two mutually diametrically opposite portions of the side surfaces (16) of the rail (4, 20) are in each case one connection channel (14, 14a, 14b) that is connected to one of the at least one longitudinal channel (12, 12a, 12b, 12c, 12d, 12e).

8. Hydrogen pressure tank system (2) according to Claim 1 or 5, 6 or 7, wherein the rail (4, 20) has a rib structure on the side face (16) for supply or removal of heat.