Method for manufacturing fuel rails for pressure vessel systems, fuel rails, pressure vessel systems, and automobiles

Abstract

The technologies disclosed herein relate, according to the present invention, to a method for manufacturing a fuel rail for a pressure vessel system, a fuel rail, a pressure vessel system, and an automobile. [Solution] The solution includes the steps of preparing a straight fuel pipeline and forming a plurality of rail connecting portions 210, wherein these rail connecting portions 210 have an enlarged cross-sectional area relative to the prepared fuel pipeline, and the rail connecting portions 210 are formed as one piece with the fuel pipeline.

Description

Technical Field

[0001] Automobiles equipped with pressure vessels are known from the prior art. Usually, up to three large pressure vessels are provided for one automobile. Such pressure vessels are relatively difficult to incorporate into an automobile due to their dimensions. Furthermore, there is a vehicle concept of incorporating a clearly larger number of pressure vessels into an automobile, in which case all individual pressure vessels are substantially formed in a tubular shape. A pressure vessel system having a plurality of storage tubes can be well incorporated into an existing configuration space. The disadvantage is that such a pressure vessel system is relatively complex and costly because it has to meet the same requirements as conventional pressure vessel systems with respect to driving range and component safety. Furthermore, having a relatively large number of interfaces increases the possibility of locations where leaks can occur.

[0002] The priority problem of the technology disclosed in this specification is to reduce or eliminate at least one disadvantage of known solutions or to propose alternative means. The priority problem of the technology disclosed in this specification is in particular to propose a pressure vessel system that is relatively simple and inexpensive and optimal with respect to safety, light weight and / or configuration space. Further priority problems are achieved by the advantageous effects of the technology disclosed in this specification. The problem is solved by the subject matter of the independent claims. Advantageous configurations are described in the dependent claims.

[0003] The technology disclosed herein relates to pressure vessel systems for automobiles (e.g., passenger cars, motorcycles, and commercial vehicles). The pressure vessel system has at least one, preferably more, pressure vessels for storing fuel. The pressure vessel system is used for storing gaseous fuel under ambient environmental conditions. The pressure vessel system can be used in automobiles powered, for example, by compressed natural gas (also known as Compressed Natural Gas or CNG), liquefied natural gas (also known as Liquid Natural Gas or LNG), or hydrogen. The pressure vessel system is fluidly connected to at least one energy converter, which is configured to convert the chemical energy of the fuel into another energy form, such as a fuel cell or an internal combustion engine.

[0004] The pressure vessel may be, for example, a high-pressure gas vessel. The high-pressure gas vessel is configured to continuously store fuel at ambient temperature at a nominal working pressure (also called NWP) of at least 350 barue (= overpressure exceeding atmospheric pressure) or at least 700 barue. The pressure vessel may have a circular or elliptical cross-section. For example, multiple pressure vessels may be provided, their longitudinal axes extending parallel to each other at the assembly position. Each individual pressure vessel may have a length-to-diameter ratio of 4 to 200, preferably 5 to 100, and particularly preferably 6 to 50. The length-to-diameter ratio is the quotient where the numerator is the total length of the individual pressure vessel (e.g., the total length of the storage pipe excluding the fluid connection element) and the denominator is the maximum outer diameter of the pressure vessel. The individual pressure vessels may be placed directly adjacent to each other, for example, with a distance of less than 20 cm, or less than 15 cm, or less than 10 cm, or less than 5 cm between them. Multiple pressure vessels may be mechanically connected to each other at one end or both ends. Advantageously, it may be assumed that a common body-connecting element is provided at each end for multiple pressure vessels, allowing the pressure vessels to be mounted to the vehicle. Such a system is particularly suitable for flat mounting space in the underfloor area below the vehicle's interior. In a preferred configuration, the multiple pressure vessels, together with the body-connecting element, form a single pressure vessel configuration. Preferably, the pressure vessel configuration can be housed in a casing. Such a pressure vessel configuration (including the casing in some cases) is typically incorporated into the vehicle as a single component.

[0005] A pressure vessel has connecting members. These connecting members form the pressure vessel opening. Typically, connecting members are located at the ends of the pressure vessel. They are preferably made of metal and are often called "bosses." Preferably, connecting members are coaxial with the longitudinal axis of the pressure vessel. They are used to form a fluid connection between the fuel storage volume of the pressure vessel and the energy converter of the vehicle. Part of the connecting member extends from the pressure vessel. Another part may be incorporated into the vessel wall. In other words, the connecting member may be integrally formed with the pressure vessel or inserted into the pressure vessel. However, it is also conceivable that the connecting member is mounted on the outside of the pressure vessel. For example, the connecting member may have a section that protrudes into the vessel wall and is surrounded by a fiber-reinforced layer. Such a fiber-reinforced layer may also be called a reinforcement and is usually attached by braiding and / or wrapping. Preferably, the connecting member has an end face, which typically extends substantially parallel to a plane oriented perpendicular to the longitudinal axis of the pressure vessel. Preferably, the connecting member is connected to a common valve unit disclosed herein via a fuel guide section, rather than having a separate tank shutoff valve. In one configuration, a pipe rupture prevention valve may be provided in each fuel storage volume or on the connecting member of at least one pressure vessel, thereby preventing the outflow of fuel from the pressure vessel in the event of a fault. Such a pipe rupture prevention valve prevents an uncontrolled release of fuel in the event of a pipeline rupture in a pipeline system connected downstream of the fuel supply device and can be automatically reset when the fault is resolved.

[0006] The portion of the connecting member's outer surface that extends from the pressure vessel has a sealing surface and a curved mounting surface. The sealing surface may be formed as a frustoconical or funnel-shaped surface that tapers toward the interior of the connecting member. The sealing surface is formed to seal the fluid connection between the pressure vessel and the vehicle's fuel guide section, particularly the fuel rail disclosed herein, at the assembly position of the pressure vessel. For this purpose, the outer surface of the fuel guide section can contact the sealing surface of the connecting member directly or through a sealing element. Preferably, the outer surface of the fuel guide section is a curved, particularly preferably spherical segment-shaped, outer surface that contacts the sealing surface in at least a predetermined area. Thus, when the spherical segment-shaped outer surface of the fuel guide section and the frustoconical sealing surface abut each other, a good sealing seat can be formed. Thus, the pressure vessel can also be directed by simple means. The curved mounting surface may be formed by a spherical segment or a cylindrical surface section. The mounting surface is provided for directly or indirectly mounting the pressure vessel to at least one vehicle body coupling element.

[0007] The connecting member may be provided with a recess formed in the end face of the connecting member. The recess may be formed to accommodate, at least partially, preferably completely, a section of the fuel pipeline, particularly a rail connection. Preferably, the recess is formed in a C-shape or U-shape in cross-section along the longitudinal axis of the pressure vessel. Typically, the recess divides the end face of the connecting member into two circular or ring segments. These segments face each other. In one preferred configuration, the connecting member has (preferably divided) female threads into which (preferably divided) male threads of a pressing plate engage to fasten the rail connection. In other words, preferably, the projections forming the segments of the end face have an inner surface. This inner surface faces the section of the fuel pipeline or rail connection that will be housed in the recess when assembled. Advantageously, the female threads are provided on this inner surface.

[0008] At least one body coupling element is used to directly or indirectly attach a pressure vessel to the body of an automobile and may have any suitable shape. The connecting member or body coupling element is formed to transmit forces and moments generated from the pressure vessel during operation of the automobile to the body of the automobile at each end where the connecting member is provided. The body coupling element may have a curved, preferably spherical segmented, inner surface, the curvature of which substantially corresponds to the curvature of the outer surface of the mounting surface to form a contact surface. Fixing hardware may also be provided for body coupling. This allows for the largest possible contact surface to reliably transmit mechanical loads. In one configuration, the body coupling element may be a support to which multiple pressure vessels are attached. The support itself may be attached to the body of the automobile via body coupling points. For example, the body coupling element may be a side member or a cross member.

[0009] The mounting surface and the sealing surface are preferably provided laterally on the portion of the connecting member that extends out of the pressure vessel. The connecting member may preferably have an end face positioned on a plane that extends substantially perpendicular to the longitudinal axis of the pressure vessel. The portion of the connecting member that extends out of the pressure vessel may further have a circumferential surface on which the mounting surface and the sealing surface are provided. In one configuration, the circumferential surface may preferably extend perpendicular to the end face. The mounting surface and the sealing surface may be positioned opposite each other in the assembly position so that they can be fastened to each other by at least one identical fastening means (e.g., a screw). In one other configuration, the mounting surface may be provided laterally on the portion of the connecting member that extends out of the pressure vessel, and the sealing surface may be provided on the end face of the extended portion of the connecting member. That is, advantageously, the body connection may be separated from the fluid connection. This allows for a more robust configuration, which may be advantageous in terms of the design and / or assembly of such a system. The configuration of the connecting members disclosed herein is particularly advantageous and can be combined with conventional fuel guide sections or with the fuel rails disclosed herein.

[0010] Fuel guide sections and / or body coupling elements can preferably clamp the protruding portion of a connecting member to form a support point. That is, the connecting member and especially the mounting surface are used to support a pressure vessel in a vehicle. Such support via the end of the pressure vessel is also called a "neck mount".

[0011] A pressure vessel system or pressure vessel may be configured such that fuel can flow in or out at the ends of the pressure vessel through fluid passages that extend laterally, particularly perpendicular to the longitudinal axis of the pressure vessel. In an alternative configuration, the pressure vessel system or pressure vessel may be formed such that fuel can flow in or out through fluid passages that extend parallel to the longitudinal axis of the pressure vessel. Particularly preferably, it is assumed that no (tank shut-off) valves forming (together) fluid passages are screwed into the connecting members.

[0012] Fuel guide sections are used to fill pressure vessels with fuel and / or to remove fuel from pressure vessels. Preferably, the pressure in the fuel guide section substantially corresponds to the internal pressure of the pressure vessel. Individual pressure vessels are usually connected in parallel. Multiple pressure vessels are fluidly connected to each other without interruption. "Without interruption" in this context means that, in the absence of operational errors, there are no valves between the individual pressure vessels that would interrupt these fluid connections. Therefore, the fuel pressures in different pressure vessels are usually substantially the same.

[0013] When a pressure vessel system includes multiple pressure vessels, at least one fuel guide section disclosed herein may preferably be formed as a fuel rail. The fuel rail may also be called a high-pressure fuel rail. The fuel rail is typically located upstream of a (high-pressure) pressure reducer. Essentially, such a fuel rail may be configured in a manner similar to a high-pressure injection rail in an internal combustion engine. Preferably, the fuel rail has multiple rail couplings for direct connection to a pressure vessel. Advantageously, the individual rail couplings are located directly in the rail casing and / or are all equally spaced from one another. The fuel rail is preferably formed to withstand substantially the same pressure as the pressure vessel to which it is connected.

[0014] The fuel rail may be formed to have substantially bending stiffness. In this context, bending stiffness means that the fuel rail is rigid against bending, or that only minor bending occurs during the functional use of the fuel rail that does not affect its function. In an alternative configuration, the fuel rail may be formed so that it can compensate for positional changes of the pressure vessel, particularly positional changes of the connecting members of the pressure vessel. Positional changes are the deviation between the actual position of the pressure vessel (during operation, manufacturing, maintenance, or other circumstances) and the target position taken during manufacturing. Positional changes occur, for example, due to the expansion of components (e.g., the pressure vessel) due to changes in internal pressure and / or temperature. In addition, positional changes (positional deviations) may occur due to manufacturing errors. The fuel rail may be formed to allow for error compensation perpendicular to the longitudinal axis of the pressure vessel in the pressure vessel system.

[0015] In a preferred configuration, the fuel rail is not manufactured from a special casing, but from a fuel conduit or fuel pipe, preferably a metal pipe, and particularly preferably a special steel pipe. Advantageously, the fuel rail has only one fuel conduit that connects multiple rail connections (e.g., at least three or at least five rail connections) to each other without providing separate sealing points between the rail connections. Preferably, the fuel conduit has a wall thickness of 0.75 mm to 5 mm, or 1 mm to 3.5 mm, or 1.5 mm to 2 mm. Preferably, the fuel conduit has an outer diameter of 4 mm to 15 mm, or 5 mm to 12 mm, or 6 mm to 10 mm. Preferably, the fuel conduit is circularly formed. Similarly, it is conceivable that the fuel conduit has a polygonal cross-sectional geometry. In this case, the outer diameter corresponds to the maximum outer distance between the faces facing each other, in the case of a polygon with an even number of angles (e.g., a rectangle). For regular polygons with an odd number of angles (e.g., pentagons), the outer diameter corresponds to the diameter of the circle defined by the outer vertices of the polygon. For elliptical cross-sectional geometries, the outer diameter corresponds to the maximum outer diameter.

[0016] Fuel pipelines allow fuel rails to be manufactured particularly inexpensively and with low failure rate.

[0017] Each rail joint of a fuel rail has a cross-sectional area that is enlarged perpendicular to the longitudinal axis of the fuel pipeline in the region of the rail joint, with respect to the region of the fuel pipeline directly adjacent to the rail joint. The rail joint is advantageously formed as a single piece or integrally with the fuel pipeline. Preferably, the rail joint is manufactured from the same material as the fuel pipeline. "As a single piece" in this context means that the rail joint cannot be non-destructively separated from the fuel pipeline, or is formed from the fuel pipeline itself, possibly by the adhesion of additional material. If further components form the rail joint together, these components are materially connected to the fuel pipeline. In other words, the rail joint is typically a thickened region of the fuel pipeline, manufactured, for example, by deformation, by material adhesion, and / or material removal, and the fuel pipeline itself is also provided within the thickened region. The fuel rail may, in particular, be manufactured from a high-pressure pipeline. Preferably, at least one of the rail connections is formed at a distance from the end of the fuel line. That is, the rail connections are not located at the ends of the fuel line, but somewhere between the ends of the fuel line. In many cases, the rail connections are located at equal intervals from each other. At least one rail connection is usually provided with a rail connection hole. The rail connection hole is a through-hole that forms a fluid connection between the pressure vessel and the fluid passage inside the fuel line. Advantageously, this through-hole may be a drilled hole, i.e., formed by cutting. The rail connection hole extends usually at an angle, preferably perpendicular, to the longitudinal axis of the fuel line or the fluid passage formed within the fuel line.

[0018] The fuel rail may have curved sub-regions. These curved sub-regions can be formed, in particular, by bending the fuel line. Advantageously, the stresses potentially applied to the fuel rail by the bending can be reduced, at least by heat treatment. The curved sub-regions are advantageously located between two rail joints. The curved sub-regions are configured to compensate, at their assembly position, for example, for positional changes and / or angular displacements of pressure vessels that may occur perpendicular to the longitudinal axis of the pressure vessels of substantially parallel-arranged pressure vessels. Furthermore, they can compensate for thermal stresses due to various thermal expansions. For this purpose, such sub-regions of the fuel rail, formed by the curved fuel rail, can be substantially elastically deformable. The shape or extension of the fuel line is configured in the curved sub-regions precisely for this purpose. Preferably, the multiple rail joints are located on a common axis, with the curved sub-regions extending, at least partially, away from this common axis. For example, the distance from the common axis may be at least 4 cm, or at least 6 cm, or at least 8 cm. Advantageously, a fuel rail is proposed in which the length of the fuel rail between two rail connections is greater than the direct distance between the sealing surfaces of two adjacent pressure vessels, thereby allowing for good compensation of any errors that may arise. The fuel rail, particularly the curved portion, may be formed in a meander or zigzag shape in at least a predetermined area. Advantageously, at least one section extends at an angle to the common axis, particularly preferably perpendicularly, and this section is at least 4 cm, or at least 6 cm, or at least 8 cm. The curved portion, at the assembly position, at least partially intrudes into an intermediate area between two directly adjacent pressure vessels. Such an intermediate area occurs in the pressure vessel, particularly in the tapering dome area. This allows for a particularly space-saving arrangement of the fuel rail.

[0019] At least one fuel rail and at least one body coupling element can each clamp multiple pressure vessels. Therefore, advantageously, a simple, space-saving, and cost-effective pressure vessel system is obtained that can be assembled easily, reliably, and quickly.

[0020] According to the technology disclosed herein, at least one thermally activated pressure relief device can be connected directly to at least one fuel rail disclosed herein without the need for a separate piping section. Alternatively or additionally, at least one thermally activated pressure relief device may be provided in at least one pressure vessel, preferably in each pressure vessel, preferably at the distal end, the proximal end, or both ends with respect to the fuel guide section. For example, the thermally activated pressure relief device may be provided on a connecting member and / or on a corresponding end member at the opposite end of the pressure vessel. A thermally activated pressure relief device, also called a Thermal Pressure Relief Device (TPRD) or thermal safety device, is typically provided adjacent to the pressure vessel. During heating (e.g., by a flame), the TPRD releases fuel stored in the pressure vessel into the surroundings. As soon as the trigger temperature of the TPRD is exceeded (i.e., when it is thermally activated), the pressure relief device releases fuel. A trigger piping may also be provided. Such a system for thermal pressure relief is described, for example, in German Patent Application Publication No. 102015222252.

[0021] At least one valve unit may be connected directly to the fuel rail without any other pipeline section, and this valve unit has at least one non-energized shut-off valve. Particularly preferably, multiple pressure vessels are fluidly connected to the valve without interruption during the functional operation of the vehicle. The valve is one whose inlet pressure corresponds (substantially) to the pressure of the multiple pressure vessels. The valve is, in particular, an open-loop controllable or closed-loop controllable valve. In European Commission Regulation (EU) 406 / 2010 of 26 April 2010, relating to the implementation of Regulation (EC) 79 / 2009 of the European Parliament and the Council relating to the type approval of hydrogen vehicles, such a tank shut-off valve is also called the first valve. This valve is used, in particular, in normal operation to interrupt the fluid connection between individual pressure vessels and components located downstream of the fuel supply system, for example, when the vehicle is parked and / or when a functional error is detected and the fluid connection should be interrupted for safety reasons. There is usually no non-energized shut-off valve between the fuel storage volume of the pressure vessel and the rail connection.

[0022] The technology disclosed herein further relates to an automobile equipped with the pressure vessel system disclosed herein or the pressure vessel disclosed herein. The underfloor area of ​​the automobile may be divided into a plurality of underfloor assembly areas by at least one support. Such a support may be provided to transmit the load applied to the automobile during a side collision to a sill located on the opposite side. A fuel rail may be provided on or within the surface of a plurality or all of the underfloor assembly areas, to which a pressure vessel located in each underfloor assembly area is connected. In one configuration, depending on the customer's preference, a high-voltage battery or pressure vessel system may be provided in each underfloor assembly area.

[0023] The technology disclosed herein further relates to a method for manufacturing a fuel rail for a pressure vessel system having multiple pressure vessels for storing fuel, in particular a method for manufacturing a fuel rail disclosed herein and / or a method for manufacturing a fuel rail for a pressure vessel system disclosed herein. This method comprises the following steps, namely: -The step of preparing a (preferably straight) fuel pipeline, - A step of forming multiple rail connections, wherein these rail connections have a cross-sectional area that is enlarged perpendicular to the axis AA of the fuel line with respect to the prepared fuel line, and the rail connections are formed in a one-piece, non-destructively separable manner from the fuel line. Includes.

[0024] This method may include the step of providing rail connection holes in the formed rail connection portion. This step may be performed before or after the formation of the curved portion. The rail connection holes may be, for example, holes that are advantageously provided before or after the formation of the curved portion.

[0025] This method may include the step of providing a curved portion, particularly a curved portion as disclosed herein, in a fuel pipeline.

[0026] This method may include a step of forming multiple rail connections by a deformation method, particularly by rotary swaging. Rotary swaging or net-shape forming is a progressive pressurized deformation method in which a deformation tool is concentrically positioned around the workpiece. The tool vibrates at a high frequency and with a short stroke. In this case, relative rotational motion occurs between the tool and the workpiece.

[0027] Alternatively or additionally, an enclosure may be made by a material deposition method, such as welding, casting, or injection molding. The geometry of the rail connection may also be formed by fitting a semi-finished product. The semi-finished product can then be compressed, adhered, plastically deformed, brazed, or welded. For example, a sleeve having a rail connection geometry can be attached and this sleeve is joined to the fuel line in a materially connecting manner.

[0028] Alternatively or additionally, a removal method or a cutting method can be used to form the rail connection. A method combining the above methods is also conceivable. The geometry of the rail connection does not have to be spherical, and another geometry can also be provided. Usually, the front end of the rail connection is substantially formed in a spherical segment shape in order to form a fluid connection that is sealed. Preferably, for example, it can be assumed that only the front end of the rail connection is substantially in the shape of a spherical segment. For example, the rail connection may be formed in a cylindrical shape, particularly with a dome as the front end. It is also conceivable that at least one sealing element, such as an O-ring, is provided in an assembled state on the wall of the fluid passage provided in the connecting member. The sealing element may be supported, for example, on one cylindrical outer wall section of the rail connection and can press against the inner wall of the fluid passage of the connecting element.

[0029] In other words, the method for manufacturing a fuel rail disclosed in this specification can include the following steps: 1. Prepare a straight fuel line, and then 2. Manufacture a wall thickness portion having an appropriate geometry (e.g., by rotary swaging), and then 3. Provide a connection hole in the wall thickness portion / geometry, and then 4. Bend the fuel line into a desired shape.

[0030] In other words, the connection of the pressure vessel can be made by a fuel line that is locally compressed into a spherical shape. This sphere may have a radial opening at one point. This creates a "mini T-shaped member" that is formed in one piece. The portion of the sphere with the hole is attached to the appropriate part of the vessel by a suitable clamping device.

[0031] The technologies disclosed herein will be described below with reference to the drawings. [Brief explanation of the drawing]

[0032] [Figure 1] This is a schematic cross-sectional view of the first configuration of the technology disclosed herein. [Figure 2] This is a schematic diagram of another configuration of the technology disclosed herein. [Figure 3] This is a schematic diagram of a fuel rail 200 according to the technology disclosed herein. [Figure 4] Figure 3 is a schematic diagram of the positioned fuel rail 200. [Figure 5] Figure 3 is a schematic diagram of the assembled fuel rail 200, which is attached to the vehicle body. [Figure 6] Figure 5 is a schematic cross-sectional view of an embodiment. [Figure 7] This is a schematic cross-sectional view showing another configuration of the technology disclosed herein. [Figure 8] This is a schematic cross-sectional view showing another configuration of the technology disclosed herein. [Figure 9] This is a schematic cross-sectional view showing another configuration of the technology disclosed herein. [Figure 10] This is a schematic diagram showing the underfloor area of ​​an automobile according to another embodiment. [Figure 11] This is a schematic diagram showing the underfloor area of ​​an automobile according to another embodiment. [Figure 12] This is a schematic diagram of another configuration of the technology disclosed herein. [Figure 13] Figure 12 is a perspective view showing a part of the configuration. [Figure 14] This is a cross-sectional view of a connecting member along the longitudinal axis of a pressure vessel. [Modes for carrying out the invention]

[0033] Figure 1 shows a schematic cross-sectional view of a first configuration of the technology disclosed herein. Here, three pressure vessels 100 are shown, each of which has one connecting portion 130. It is also conceivable that further pressure vessels 100 together form a pressure vessel system. Here, the connecting portion 130 is integrally inserted into the pressure vessel wall. The pressure vessel walls of the pressure vessels 100 are formed here by a liner 110 and a fiber-reinforced layer 120, respectively. The connecting member 130 here has a coaxially extending fuel passage, which opens into a frustoconical or funnel-shaped region on the end face of the connecting member 130. This region is provided with a sealing surface 132 of the connecting member 130. In this funnel-shaped region, a piping system leading to a fuel consumer is in contact with each pressure vessel 100. For this purpose, the piping system has a piping connection, which each includes a cap nut and a piping end tapering toward the end. This piping system forms a fuel guide section. The piping system here includes a number of individual piping elements, such as conduits, T-connectors, and cap nuts. Furthermore, a body coupling element 300 is shown, each of which forms a receiving portion for the curved mounting surface 134 of the connecting member. The body coupling elements 300 are formed separately here. Alternatively, one common body coupling element 300 may be provided for all three pressure vessels 100. The mounting surface 134 has substantially the same curvature as the inner surface of each body coupling element 300 at its contact surface. The mounting surface 134 formed laterally on the outer surface of the protruding portion of the connecting member is pressed against the body coupling element 300, thereby fixing its position. This configuration allows the individual pressure vessels 100 to be rotated to the correct position during assembly, even before their installation. In other words, in this case, advantageously, the fluid connection is functionally separated from the vehicle body connection by the mounting surface 134 via the sealing surface 132, so that forces and moments for holding the pressure vessel are not transmitted through the piping system.

[0034] Figure 2 shows a schematic cross-sectional view of an embodiment comprising multiple pressure vessels 100. The pressure vessels 100 are provided here axially parallel to the plane of the underfloor area of ​​the automobile. The fuel guide section 200 is formed here as a fuel rail 200. The fuel rail 200 is manufactured from a single pipe (=fuel conduit), which has a thick-walled, substantially spherical rail connector 210. Through this rail connector 210, a fluid connection is formed to each individual connecting member 130 of the pressure vessel 100. The rail connector 210 is formed as a single piece in the conduit. The rail connector 210 is further manufactured from the same material as the conduit, for example, special steel. The substantially spherical outer surface of the rail connector 210 is in close contact with the conical sealing surface 132 of each connecting member 130. To form a sealing seat, the spherical outer surface of the rail connector 210 is pressed against the sealing surface 132. For this purpose, one pressing plate 330 is provided on each opposite side of the seal seat, and these pressing plates are fastened to each connecting member 130 of each pressure vessel 100 by two fastening means 400 (e.g., screws). During assembly, each pressure vessel 100 is already aligned by contact between the sealing surface 132 and the rail connecting portion 210 before being mechanically attached to the body coupling element 300. Furthermore, the body coupling element 300 has two rubber support portions 320, which may be formed as known by the support portions of the internal combustion engine in the engine compartment.

[0035] In this configuration, the fuel rail 200 is formed substantially straight and does not have curved portions to compensate for errors. The attachment of the connecting member 130 to the common body coupling element 300 and the further assembly of the pressure vessel 100 into the vehicle are not shown in detail here. For this reason, at the assembly position, the underside of the pressure vessel may be provided with components of one common casing of the pressure vessel system, such as a bottom plate and a bottom slab. Furthermore, other components such as a pipe rupture prevention device or a heat-activated pressure relief valve are not shown.

[0036] Figure 3 shows a schematic diagram of the fuel rail 200. The rail connection holes 212 of the rail connection sections 210 form a common axis AA. The region of the fuel rail 200 located on the common axis AA extends substantially straight. Between each of the two rail connection sections 210, there is a curved sub-region 211. The curved sub-region 211 of the fuel rail 200 is a region where the fuel pipeline, of which a portion forms the fuel rail 200, is curved. The curved sub-region 211 is not located on the common axis AA, but extends at a distance from the axis AA. The curved sub-region 211 may be formed in a different form. In the configuration shown herein, the curved sub-region 211 is formed such that the entire fuel rail 200 has a single meander-like extension or meander-like shape. However, the curved sub-region may have a different configuration, for example, a zigzag shape. The curved portion region 211 is formed so that the fuel rail 200 can effectively compensate for positional changes or errors in the direction of axis AA. For this purpose, the curved portion region has a section that extends at an angle to axis AA, or preferably perpendicularly. This allows a greater bending load than a tensile load to be applied to this section for error compensation. The fuel rail 200 with the curved portion region 211 shown herein can also be used in configurations shown in other drawings in which the fuel rail 200 does not have a curved portion region.

[0037] Figure 4 shows a schematic diagram of an embodiment with the fuel rail 200 according to Figure 3. The fuel rail 200 is mounted on the connector 130. The spherical outer surface of the rail connector 210 rests on the sealing area 132 of the connector 130. The end face of the connector 130 is provided with a U-shaped recess in cross-section, within which the corresponding rail connector 210 is fully housed. The recess is formed on both sides of the fuel rail 200, with sufficient space inside the recess to allow for a predetermined angular displacement for rotation around the longitudinal axis LL of the pressure vessel. The end face is provided with two threads for receiving the fastening means 400 (see Figure 5). The recess is formed here as a passage extending straight in plan view, provided on the circular end face of the connector 130. Thus, the recess divides the end face into two circular segments or sections, each having a hole for the fastening means 400 (not shown). The curved portion region 211 is located between or slightly above the connecting portions 130 and directly adjacent to the pole caps of the pressure vessel 100. Thus, a particularly space-saving structure is achieved. The mounting surface 134 is provided on the circumferential surface of the outer surface of each connecting member 130. For vehicle body coupling, in a preferred configuration, this circumferential surface is surrounded and clamped.

[0038] Figure 5 shows a schematic diagram of the embodiment according to Figure 4 in its assembled position. The vehicle body coupling element 300 is a support that may have a substantially U-shaped cross-section. The support may be, for example, a cross member or side member of an automobile. Multiple pressure vessels 100 are attached to the vehicle body coupling element 300, each via a connecting member 130. U-shaped clamps 340 surround the mounting surfaces 134 of the connecting members 130. The U-shaped clamps 340 are substantially Ω-shaped and are each attached to the vehicle body coupling element 300 via screws. Preferably, vehicle body coupling elements 300 are provided at both ends of the pressure vessel 100, and these vehicle body coupling elements may be configured differently. Through these vehicle body coupling elements 300, mechanical loads generated during operation can be transmitted from the pressure vessel to the vehicle body. The fuel rail 200 is pressed against the sealing surface 132 by a pressing plate 330 in the area of ​​the rail coupling portion 210. For this purpose, the pressure plate 330 is preloaded axially by the fastening means 400 in the direction of the longitudinal axis LL of the pressure vessel (see Figure 1). Thus, advantageously, mechanical body coupling and fluid connection can be achieved with minimal configuration space. Moreover, assembly is simple and quick. Furthermore, any rotational positional errors that may occur in the pressure vessel 100 are not significant. In addition, the bottom plate 700 is shown. Mounting elements 710 protrude from the bottom plate 700. These mounting elements 710 also serve to stabilize the bottom plate 700. Other elements of the pressure vessel system, such as pipe rupture prevention devices and thermal pressure relief devices, are not shown.

[0039] Figure 6 shows a schematic cross-sectional view of a pressure vessel 100 and a fuel rail 200. The connecting member 130 is also integrally formed with the pressure vessel 100 and is partially surrounded by the fiber-reinforced layer 120 of the pressure vessel wall. The end face is provided with a recess having a U-shaped cross-sectional geometry. This recess has a central hole that connects the fuel storage volume V to a conical opening in the recess. The outer circumferential surface of the connecting member 130 has a circumferential surface that forms a mounting surface 134. This mounting surface 134 is surrounded by a U-shaped clamp 340 in the assembled state. The pressing plate 330 protrudes into the recess of the connecting member 130 and contacts the rail connection portion 210. In the contact area, the pressing plate 330 has a surface shape that corresponds to the outer surface of the rail connection portion 210.

[0040] Figure 7 shows a schematic cross-sectional view of another embodiment. The fuel rail 200 here has three rail connectors 210 that fluidly connect three pressure vessels 100 to each other without interruption. Other components that may be provided, such as a pipe rupture prevention device or a heat-activated pressure relief valve, are not shown. The sealing surface 132 of the connecting member 130 is directed by the rail connectors 210 and simultaneously pushed downward. The body coupling element 300, particularly its inner surface, applies a reaction force. This holds the position of the connecting member 130. A mounting element 710 protrudes from the bottom plate 700. This mounting element 710 also serves to stabilize the bottom plate 700. To the side of the fuel rail 200, a valve unit 220 is directly attached to the fuel rail 200. The valve unit 220 is provided with an unenergized shut-off valve, which shuts off the fuel supply to downstream components of the fuel supply system (e.g., components of the anode subsystem of the fuel cell system). Typically, a pressure reducer is provided adjacent to or within the valve unit 220 to reduce the pressure to a medium pressure range (usually between 5 and 50 bar). Here, a take-out conduit connector 202 is led out from the valve unit 220, which may be connected to, for example, a take-out conduit (not shown). At the other end of the fuel rail, there is a refueling conduit connector 204, which may be connected to a refueling conduit. Instead of conduits leading to further components, another fuel rail or another element may be directly connected thereto.

[0041] Figure 8 shows a schematic cross-sectional view of another embodiment. Only the important differences from the embodiment described above are described in detail below. For other points, refer to the description of the other drawings. The fuel rail 200 has rail connections 210 for the pressure vessel 100 and connections or pipe connections 202, 204 for the valve unit 220, in addition to another pressure relief connection 242 for connecting a thermally activated pressure relief device 240. When a thermal event occurs, the pressure relief device 240 is triggered to relieve pressure in all three pressure vessels 100. Preferably, a pipe rupture prevention device is provided at the end of the fuel rail 200, particularly on the surface or inside the pipe connections 202, 204, and / or within the valve unit 220, which disconnects the fluid connection to adjacent components of the vehicle's fuel supply system when (i) damage to the pressure vessel 100 and / or the fuel rail 200 is likely to occur, and / or (ii) when the pressure relief device 240 should be activated. In a preferred configuration, a heat-activated pressure relief device 240 is also provided at the end opposite to the connecting member 130. This figure schematically shows support members 500 that divide individual underfloor assembly spaces. The left support member 500 extends downward from the bottom surface 600 of the vehicle. To overcome this, the fuel supply line connection 204 is positioned downward. Therefore, in this case, the fuel supply line may be laid on the underside of the support member 500. On the other hand, at the right edge, it can be seen that the support member 500 extends upward from the bottom plate 700. At the right edge, the fuel line may be laid beyond the support member 500. The specific arrangement of the lines may be adapted according to the assembly situation.

[0042] Figure 9 shows a schematic cross-sectional view of another embodiment. Only the important differences from the embodiment described above are described in detail below; other points are referred to in the descriptions of the other drawings. The fuel rail 200 additionally has another valve unit 230 which may be provided at the other end of the fuel rail 200. This valve unit 230 may be provided with, for example, a check valve which blocks the backflow of fuel into the upstream region of the tank replenishment path. This unit may be provided with a heat-activated pressure relief device 240 (not shown).

[0043] Figure 10 shows a plan view of the underfloor area of ​​the automobile. The support 500 divides the underfloor area into various underfloor assembly areas. The underfloor assembly areas are substantially the same size here. Each support 500 here extends from one side sill to the other side sill in the lateral direction of the vehicle and substantially contributes to the rigidity of the body structure. In the right underfloor assembly area, a pressure vessel system is provided. The pressure vessel system includes three pressure vessels 100 located between two support 500. These pressure vessels 100 are arranged parallel to each other and parallel to the support 500. One end of each pressure vessel 100 is connected to a fuel rail 200 via a connecting member 130. The opposite end of each pressure vessel 100 is provided with a heat-activated pressure relief device 240. The fuel rail 200 forms a fuel guide section. A fuel line 270 is connected to one end of the fuel rail 200, which is used as a refueling line and is connected to the vehicle's tank coupling (not shown). The other end of the fuel rail 200 is provided with a valve unit 220 equipped with an unenergized shut-off valve. The unenergized shut-off valve is controlled in a closed-loop or open-loop manner by the vehicle's control equipment. Operation of the valve allows for the extraction of fuel from the pressure vessel. The valve unit 220 is fluidly connected to a pressure reducer 290 via the fuel line 270. Downstream of the pressure reducer 290 is another fuel line 270 leading to the vehicle's energy converter (not shown). Depending on the vehicle configuration, another pressure vessel and another fuel rail 200 may be provided in a different underfloor assembly area, fluidly connected in series or parallel to the illustrated pressure vessel. A high-voltage accumulator battery may also be provided in one or more underfloor assembly areas. It is also conceivable that the same vehicle structure could be used for a purely battery-electric vehicle without a pressure vessel system.

[0044] Figure 11 shows another plan view of the underfloor area of ​​the vehicle. In this configuration, four fuel rails 200 are provided, with each fuel rail 200 containing three pressure vessels 100 located in one underfloor area. The fuel rails 200 are connected in series here, and each is connected to the others by a fuel line 270. The fuel line 270 is guided around a support 500. A valve unit 220 is provided between the pressure reducer 290 and the fuel rails 200, and this valve unit also has an unenergized shut-off valve that shuts off all pressure vessels 100 located in the underfloor area from other fuel supply devices. Only one of the four fuel rails 200 is connected to a fuel line 270 that functions as a refueling line. The two middle fuel rails 200 are connected only to adjacent fuel rails 200.

[0045] Figure 12 shows a pressure vessel system with an alternative configuration of the pressing plate 330 and the fastening means 400, which will be described in detail in relation to Figure 13. In other respects, the pressure vessel system is appropriately configured in the same way as described in relation to the drawings above.

[0046] Figure 13 shows a perspective view of a portion of the pressure vessel system according to Figure 12. The fuel rail 200 extends meanderingly here. The sections of the fuel pipeline, each containing a rail connector 210, extend parallel to each other. Each rail connector 210 has one rail connector connection hole 212. The rail connector connection hole 212 here forms a fluid connection between the fuel storage volume V of the pressure vessel 100 and the fluid passage of the fuel pipeline formed as a pipe. Here, the front end 214 that abuts the sealing surface 132 of the connecting member 130 is curved and preferably formed substantially spherically. In the assembled state, the front end 214 forms an element that seals together with the sealing surface 132. However, other sealing systems are also conceivable. As in the configuration of Figure 4, a recess U is provided, and the fuel pipeline is arranged within this recess together with the rail connector 210. The recess U extends inward from the end face of the connecting member 130 in the direction of the longitudinal axis of the pressure vessel and in the direction of the fuel storage volume V. That is, the recess U is formed by recessing it relative to the end face. The recess U divides the end face into two end face segments, which are formed here as opposing ring segments. In other words, these ring segments are substantially C-shaped projections extending outward from the bottom of the recess U in the direction of the longitudinal axis of the pressure vessel. The recess U has a central region, which is enlarged in the plan view looking at the end face and is formed here as a circle. The recess, or the projection formed by the recess U, is provided with female threads in the central region. A pressing plate 330 is mounted in this central region. The pressing plate 330 has male threads on its edges that engage with the divided female threads of the recess. The pressing plate 330 further has a screw head driver (e.g., hexagonal socket, hexalobular socket, internal teeth, etc.) formed to screw the pressing plate 330 into the central region of the connecting member 130, thereby pressing the rail connecting portion 210 against the sealing surface 132.

[0047] Figure 14 shows a cross-sectional view of the connecting member 130 along the longitudinal axis of the pressure vessel. The connecting member 130 is provided with a fluid passage that extends coaxially with respect to the longitudinal axis of the pressure vessel. The diameter of the fluid passage is enlarged by a hole near the end face. In this region, a portion of the rail connector 210 is housed in the connecting member 130. Here, a different sealing concept is employed, so the front end of the rail connector 210 is formed flat rather than substantially spherical segment-shaped. Instead, an O-ring is provided between the wall of the fluid passage and the cylindrical outer wall section of the rail connector 210. A groove is provided in the outer wall section for good fixation.

[0048] In other words, the pressing plate 330 is a central pressure thread formed to press the sealing area via a divided thread after joining the conduit with a spherical connector to the grooved milled portion of the boss. Thus, advantageously, the required space, weight, and / or the effort of screwing can be reduced.

[0049] An add-on with a flexible fuel rail featuring an integrated rail connector (i.e., a "mini T-shaped member") (i.e., the use of a relatively flexible high-pressure pipeline) can be connected very compactly within a relatively small boss for small pressure vessel diameters. Central screw fixing offers many advantages over other fixings of the pressing plate, such as a simpler screw fixing process and reduced material volume, resulting in weight and cost advantages. Furthermore, this example provides good protection against mechanical damage in the event of impact. Brazing material connection of branch members asymmetrically with respect to the pipeline axis is particularly inexpensive. Advantageously, the sealing function rather than the function of transmitting tensile forces is suitable for brazing. The pressing force of the fixing screw can be properly guided around the pipeline through the branch member. Under pressure, the pipeline is pressed from the inside towards the branch, and the brazed joint is substantially pressed against this sleeve-like portion.

[0050] The concept of “substantially” (e.g., “substantially having bending stiffness”) in the context of the technology disclosed herein includes, respectively, an exact property or exact value (e.g., “bending stiffness”), as well as a deviation that does not affect the function of the property / value (e.g., “acceptable deviation from bending stiffness”).

[0051] The above description of the present invention should be used for illustrative purposes only and is not intended to limit the invention. Within the scope of the invention, various modifications and improvements are possible without departing from the scope of the invention or its equivalents. For example, any number of pressure vessels 100 can be connected to the fuel rail 200 instead of three pressure vessels (see Figure 12). A different number of fuel rails 200 can be provided instead of one fuel rail 200 or four fuel rails 200. In one configuration, the fuel rail 200 can extend throughout the entire underfloor area. Advantageously, a fuel conduit 270 can be formed separated from one fuel rail 200 by, for example, guiding the fuel rail 200 around a support 500. The pressure vessel system disclosed herein may be provided with the fuel rail 200 disclosed herein or with other fuel rails. [Explanation of symbols]

[0052] 100 Pressure Vessels 110 Raina 120 fiber-reinforced layer 130 Connecting Member 132 sealing surface 134 Mounting surface 200 Fuel Guide Classification 202 Outlet conduit connection 204 Fuel supply pipeline connection 210 Rail connection section 211 Curved subregion 212 Rail connection hole 214 Front end 220,230 valve units 240 Heat-activated pressure relief device 242 Pressure relief connection 250 Pipe rupture prevention valve 270 Fuel line 290 Pressure reducer 300 Body connecting element 320 Rubber support part 330 Pressure Plate 340 U-shaped clamp 400 Fastening methods 410 Tightening element 500 support 600 base 700 Bottom Plate 710 Mounting element LL Pressure vessel longitudinal axis AA axis U-shaped recess V Fuel storage volume Z intermediate area

Claims

1. A fuel rail (200) for a pressure vessel system having a plurality of pressure vessels (100) for storing fuel, comprising a fuel line and a plurality of rail connecting portions (210), wherein the rail connecting portions (210) have an enlarged cross-sectional area with respect to the fuel line, the rail connecting portions (210) are formed as one piece with the fuel line, and at least one of the rail connecting portions (210) is formed at a distance from the end of the fuel line.

2. The fuel rail (200) according to claim 1, further having a curved portion (211), the curved portion (211) being provided between two rail connecting portions (210), and the curved portion (211) being formed to compensate for positional changes of the pressure vessel (100) at its assembly position.

3. A fuel rail (200) according to claim 1 or 2, wherein a plurality of rail connecting portions (210) are arranged on a single common axis (A-A) to form the axis, and the curved portion region (211) extends at least partially away from the axis (A-A).

4. The fuel rail (200) according to any one of claims 1 to 3, wherein the fuel rail (200), in particular the curved portion region (211), is formed in a meander or zigzag shape in at least a predetermined area.

5. The rail connecting portion (210) is provided with a rail connecting portion connection hole (212), and the rail connecting portion connection hole opens into the fuel pipeline at an angle with respect to the longitudinal axis of the fuel pipeline, according to any one of claims 1 to 4, the fuel rail (200).

6. The fuel rail (200) according to any one of claims 1 to 5, wherein the front end portion (214) of the rail connecting portion (210) is substantially formed in the shape of a spherical segment.

7. A pressure vessel (100) for storing fuel, having a connecting member (130) for forming a fluid connection between the fuel storage volume (V) of the pressure vessel (100) and the energy converter of an automobile, - The connecting member (130) is led out of the pressure vessel (100) at least partially. - The outer surface of the connecting member (130) has a sealing surface (132) and a curved mounting surface (134), - The sealing surface (132) is formed to seal the fluid connection between the pressure vessel (100) and the fuel rail (200) according to any one of claims 1 to 6. - The mounting surface (134) is provided for attaching the pressure vessel (100) to at least one vehicle body coupling element (300). Pressure vessel (100).

8. - The mounting surface (134) and the sealing surface (132) are provided laterally on the portion of the connecting member (130) that is led out from the pressure vessel (100). - The mounting surface (134) and the sealing surface (132) are arranged opposite each other. The pressure vessel (100) according to claim 7.

9. The mounting surface (134) is provided laterally on the portion of the connecting member (130) that extends out from the pressure vessel (100), and the sealing surface (132) is provided on the end face of the extended portion of the connecting member (130), according to claim 7, for the pressure vessel (100).

10. The sealing surface (132) is formed as a frustoconical surface that tapers toward the interior of the connecting member (130), and / or The mounting surface (134) is formed by a spherical segment or a cylindrical surface section, according to any one of claims 7 to 9, the pressure vessel (100).

11. The pressure vessel (100) according to any one of claims 7 to 10, wherein the connecting member (130) is provided with a recess (U) recessed to the end face of the connecting member (130), and the recess (U) is formed to accommodate at least partially the fuel rail (200).

12. The connecting member (130) has a female thread, and a male thread provided on the pressing plate (330) engages with the female thread for tightening the rail connecting portion (210), the pressure vessel (100) according to any one of claims 7 to 11.

13. A pressure vessel system comprising at least one pressure vessel (100) according to any one of claims 7 to 12, wherein a body coupling element (300) for attaching the at least one pressure vessel (100) to the body of an automobile has a curved inner surface (302), the curvature of which substantially corresponds to the curvature of the outer surface of the mounting surface (134) to form a contact surface.

14. The pressure vessel system according to claim 13, wherein at least one valve unit (220, 230) is connected to the fuel rail (200), the valve unit has an unenergized shut-off valve, and no unenergized shut-off valve is provided between the fuel storage volume (V) of the pressure vessel (100) and the rail connection (210).

15. - A fuel rail (200) according to any one of claims 1 to 8, and / or - At least one pressure vessel (100) according to any one of claims 9 to 12, and / or - At least one pressure vessel system according to claim 13 or 14 A car that has [something].

16. A method for manufacturing a fuel rail (200) for a pressure vessel system having a plurality of pressure vessels (100) for storing fuel, - The step of preparing at least one fuel pipeline, - A step of forming a plurality of rail connecting portions (210), wherein each rail connecting portion (210) has an enlarged cross-sectional area relative to the prepared fuel pipeline, the rail connecting portion (210) is formed as a single piece with the fuel pipeline, and at least one of the rail connecting portions (210) is formed at a distance from the end of the fuel pipeline, A method that includes this.

17. The method according to claim 16, further comprising the step of forming a rail connection hole (212) in the formed rail connection portion (210).

18. The method according to claim 16 or 17, further comprising a step that forms a curved portion (211) in the fuel pipeline, wherein the curved portion (211) is positioned between two rail connecting portions (210).

19. The plurality of rail connecting parts (210) a. By deformation methods, particularly by rotary swaging, and / or b. By material attachment methods, particularly by welding, casting or injection molding, and / or c. By attaching the semi-finished product to the fuel pipeline in a material connection manner. A method for forming, according to any one of claims 16 to 18.

20. The method according to claim 19, wherein the semi-finished product is a semi-finished product that completely surrounds the fuel pipeline.

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