Hydraulic and / or pneumatic system, in particular fuel system, component and connection, especially for hydrogen

Abstract

Connection (60) for a hydraulic and / or pneumatic system (10), in particular a fuel system, which serves to inject gaseous fuels, especially hydrogen, and / or liquid fuels into combustion chambers (11) of an internal combustion engine, wherein a first component (61) of the hydraulic and / or pneumatic system (10) and a second component (62) of the hydraulic and / or pneumatic system (10) are provided, wherein the first component (61) has a bore (63), wherein the second component (62) has a nozzle (64) which is inserted into the bore (62) of the first component (61), and wherein a seal is formed between the first component and the second component (62) via at least one sealing element (65). It is proposed that a support element (66) connected to the first component (61) is provided and that the sealing element (65) is supported at least indirectly on the support element.Furthermore, a component (100) and a hydraulic and / or pneumatic system (10) are specified.

Description

State of the art

[0001] The invention relates to a hydraulic and / or pneumatic system, in particular a fuel system for gaseous fuels, especially hydrogen, and / or for liquid fuels. Specifically, the invention relates to the field of fuel systems for motor vehicles. The fuel system can be designed as a fuel injection system or a fuel injection system.

[0002] From DE 10 2006 040 236 A1, a fuel system for compressed gaseous fuel, in particular natural gas or hydrogen, for an internal combustion engine is known. The known fuel system comprises a common rail and a pump. Furthermore, a tank for compressed gaseous fuel, in particular natural gas or hydrogen, and an upstream pressure regulator are provided, where the pressure is reduced from the tank pressure, which can reach close to 5000 psi (34 MPa) or more, to a first reduced pressure of about 400 psi (2.8 MPa). As soon as the fuel leaves the upstream pressure regulator, it moves to a downstream pressure regulator, where the fuel pressure is reduced to about 200 psi (1.4 MPa). The fuel then moves to a control regulator.An electronic control unit operates the control regulator so that the fuel pressure at the second operating pressure, in this case approximately 200 psi, is reduced to a variable control pressure set by the electronic control unit. This allows the fuel supply via common-rail injectors to be increased or decreased.

[0003] The fuel system known from DE 10 2006 040 236 A1 has the disadvantage of high manufacturing costs to enable operation with compressed hydrogen. In particular, the material from which the individual components, especially the pressure regulators, are made must be selected to meet all existing requirements. The material selection is based on the most stringent requirement, although these can vary considerably in individual sections of the fuel system.

[0004] A fuel line for a turbomachine is known from US patent 2017 / 0219138 A1. This line features a conical sealing surface. The seal at the conical sealing surface is achieved via a conical sealing element that is inserted into a recess in the conical end of a nozzle.

[0005] The sealing method known from US 2017 / 0219138 A1 has the disadvantage that pre-assembly with leak testing is not possible, as the orientation of the fuel line can only be determined once assembly is complete and both components are in their assembly positions. This also makes assembly more complex, as, for example, tightening the relevant connecting screws is required. Furthermore, the assembled connection may prove to be insufficiently tight, necessitating extensive rework.

[0006] Furthermore, in systems with low internal pressure, such as those that can occur in hydrogen rail applications, rigid seals over conical stainless steel bodies are required, as aluminum alloys or similar materials cannot withstand the forces necessary for sealing. This necessitates either manufacturing the entire rail from stainless steel, which is costly, or requiring an additional connection for a stainless steel intermediate piece. Disclosure of the invention

[0007] The inventive connection with the features of claim 1, the inventive component with the features of claim 9, and the inventive hydraulic and / or pneumatic system with the features of claim 10 have the advantage that an improved design and function are possible. In particular, pre-assembly with leak testing and / or assembly compensation can be implemented. Additionally, a seal can optionally be implemented for applications involving the injection of hydrogen.

[0008] The measures described in the dependent claims enable advantageous further developments of the method specified in claim 1, the component specified in claim 9 and the hydraulic and / or pneumatic system specified in claim 10.

[0009] The hydraulic and / or pneumatic system is particularly preferably configured as a fuel system, especially as a fuel injection system for hydrogen. The connection and the component are preferably used for such hydraulic and / or pneumatic systems.

[0010] It is advantageous that the nozzle has a widened section at one end, which is positioned in the bore of the first component, and which is located between the end of the nozzle and the sealing element. This prevents the sealing element from shifting towards the end.

[0011] It is advantageous that the support element encompasses, and in particular encloses, a mantle-shaped outer surface of the nozzle, and that the support element is connected to the nozzle at this mantle-shaped outer surface. The mantle-shaped outer surface can, in particular, be designed to be at least substantially cylindrical. This allows for the advantageous transmission of forces, especially support forces.

[0012] A key advantage is that the support element is screwed onto an external thread formed on the outer, mantle-shaped surface of the fitting. This ensures a reliable fastening.

[0013] A key advantage is that the support element is connected to the nozzle via a snap-fit ​​connection. This allows for easy assembly.

[0014] It is advantageous that the support element has an inner collar that surrounds the nozzle, and that the sealing element is axially supported, at least indirectly, by the inner collar of the nozzle. This allows the sealing element to be positioned further within the bore of the first component, ensuring reliable positioning.

[0015] It is advantageous that at least one support disc is provided, which is axially supported on the support element, and that the sealing element is axially supported on the support element by means of this support disc. This allows the position of the supported sealing element to be adjusted or predetermined. Furthermore, the support element can potentially be designed more simply.

[0016] It is advantageous that the sealing element allows at least one axial degree of freedom of the nozzle relative to the first component. This allows for compensation of axial tolerances. Additionally, tolerance compensation for angular misalignment is possible.

[0017] It is advantageous that the sealing element is designed as a sealing ring. This allows for advantageous positioning with respect to both the first and second components, while enabling tolerance compensation on both sides.

[0018] It is advantageous that the support element is made primarily of untreated steel, plastic, or fiber-reinforced plastic. This allows for a cost-effective design of the support element. This is possible because the support element does not come into contact with the medium conveyed through the interface, particularly a fuel, and especially hydrogen.

[0019] Depending on the design, at least one of the following features and / or advantages can be realized.

[0020] Pre-assembly with a leak test can be performed to ensure leak tightness in the assembled state. This pre-assembly can be carried out, for example, on a rail, particularly a fuel rail. This approach can eliminate the need for the rail or similar component to be made of hardened steel, or the requirement for an intermediate piece made of hardened steel.

[0021] This allows for the delivery of a more complex, pre-assembled product. Costs on the final assembly side, for example on an internal combustion engine, can be reduced.

[0022] Furthermore, the design of a complex connector at at least one end of a high-pressure line can be avoided. A simple end geometry can be implemented, with sealing achieved via the sealing element.

[0023] For example, a line connected to a rail can be moved into its desired position before being mounted on the internal combustion engine, since the frictional forces on the sealing element, especially an O-ring, are comparatively low, so that rotation of the line and / or the sealing element is possible in the unpressurized state of the system.

[0024] Furthermore, tilting of the pipe or at the connection can be permitted. This allows for the compensation of tolerances. Additionally, axial adjustment of the connection can be enabled within certain limits.

[0025] The support element can serve as a cover. The support element can be designed like a nut. Suitable positive-locking connections between the first component and the support element can be achieved. Material-locking connections between the first component and the support element, particularly by welding, are also possible. The support element is designed, and in particular dimensioned, to withstand the forces that occur, especially at the hydraulic and / or pneumatic interface. Since the support element does not come into contact with fuel, hydrogen, or the like, advantageous designs using cost-effective materials are possible, especially inexpensive steels, metals, and, if applicable, plastics or fiber-reinforced plastics, depending on the specific application.

[0026] Particularly depending on the requirements for the sealing element, especially an O-shaped sealing ring, and the required support surface on the top of the sealing element, a projection on the support part serving the sealing element can also be small, which can improve tilting in the connection. This can compensate for potentially larger tolerances in this regard.

[0027] Production and the supply chain can be simplified as follows. In series production, components such as a support part in the form of a cover or nut, and optionally a support washer, can be mounted on a straight tube (spigot). Then, the radially protruding geometry at the end or head of the tube can be created for an O-ring connection. These steps can be performed at one or both ends of the tube. Finally, the tube can be bent into its desired geometry to create the required or correct shape.

[0028] Pre-assembly can be performed during the manufacturing of a rail, particularly a fuel rail. The rail can be pre-assembled including injectors, sensors, wiring harness or wiring kit, bolts, and other additional components, as well as at least one proposed connection to, for example, a pipe. A leak test can then be carried out.

[0029] For subsequent installation on an internal combustion engine, the transport of the pre-assembled rail to the engine factory and the installation itself may be necessary. This simplifies the installation on the internal combustion engine. Brief description of the drawings

[0030] Preferred embodiments of the invention are explained in more detail in the following description with reference to the accompanying drawings, in which corresponding elements are provided with matching reference numerals. The drawings show: Fig. 1 a fuel injection system designed with a fuel distributor for injecting gaseous fuels, in particular hydrogen, into combustion chambers of an internal combustion engine in an excerpted, schematic representation according to a possible embodiment of the invention; Fig. 2 a connection between a first component and a second component of the in Fig. 1 Fuel injection system shown in an excerpted, schematic sectional view according to a first embodiment and Fig. 3 a connection between a first component and a second component of the in Fig. 1 Fuel injection system shown in an excerpted, schematic sectional view according to a second embodiment. Embodiments of the invention

[0031] Fig. Figure 1 shows a fuel injection system 10 for injecting gaseous fuels, in particular hydrogen, into combustion chambers 11 of an internal combustion engine in an abridged, schematic representation according to one possible embodiment of the invention. The fuel injection system 10 can also be used for other gaseous fuels, in particular natural gas.

[0032] In a modified embodiment, the fuel system 10 can also be configured as a fuel injection system 10 for injecting gaseous and / or liquid fuels. Furthermore, in a modified embodiment, a hydraulic and / or pneumatic system 10 can also be implemented for other hydraulic and / or pneumatic applications.

[0033] The hydrogen is stored in liquid form under high pressure, for example approximately 700 bar (70 MPa), in a tank-like fuel storage unit 12. This unit can be filled via a filling port 14. Furthermore, an integrated unit 16 is arranged on the fuel storage unit 12, consisting of a tank valve for filling and dispensing hydrogen into and out of the fuel storage unit 12 and a temperature sensor for measuring the temperature of the gaseous hydrogen coming from the fuel storage unit 12.

[0034] The gaseous hydrogen travels via a pressure line 18 first to a filter 20 and from there to a high-pressure pressure regulating device (HP pressure regulator) 22. This reduces the pressure of the gaseous hydrogen, for example, to a pressure in the range of 40 bar (4 MPa). The pressure line 18 leads from the high-pressure pressure regulating device 22 to a pressure sensor 24, another filter 26, and an optional temperature control unit 28, finally to a low-pressure pressure regulating unit (LP pressure regulator) 30.

[0035] The low-pressure pressure control unit 30 comprises, by way of example, two hydraulically parallel pressure control valves 32, a low-pressure pressure sensor 34, and a safety valve in the form of a shut-off valve assembly 36. The two pressure control valves 32 are identical in design and are proportional control valves. The low-pressure pressure control unit 30 further reduces the pressure in the pressure line 18 from the inlet pressure of approximately 40 bar (4 MPa) to a pressure of, for example, approximately 15 bar (1.5 MPa).

[0036] Downstream of the low-pressure pressure control unit 30, the pressure line 18 leads to a fuel distribution device 38, in particular a rail 38, which can be designed, for example, as an elongated tube in the manner of a typical fuel rail as known from gasoline and diesel fuel systems. The gas pressure prevailing in the fuel distribution device 38 is detected by a pressure sensor 40.

[0037] Several injectors 42 are connected to the fuel distribution unit 38, which directly inject gaseous hydrogen into the combustion chambers 11 of the internal combustion engine. The gaseous hydrogen is mixed with atmospheric oxygen in the combustion chambers 11, and this mixture is ignited by a respective ignition device 46. Typically, the internal combustion engine is a two-stroke or four-stroke piston engine of a largely standard design. For example, such an internal combustion engine is used to power a motor vehicle. However, it can also be used, for example, in a stationary application to drive a generator for electricity production.

[0038] The fuel supply system 10 and its components are controlled by an electronic control unit 48, which has one or more corresponding microprocessors, a memory for program code, etc. The control unit 48 receives signals from, among others, the temperature sensor (integrated in the integrated unit 16), the pressure sensor 24, the pressure sensor 34, the pressure sensor 40, etc. The control unit 48 controls various components of the fuel supply system 10, including the low-pressure pressure regulating device 30, the safety valve 36, and the ignition devices 46. Furthermore, a control unit 50 is also controlled by the control unit 48, which in turn specifically controls the operation of the fuel storage tank 12.

[0039] Fig. Figure 2 shows a connection 60 between a first component 61 and a second component 62 of the in Fig. Figure 1 shows a simplified, schematic representation of the fuel system 10 according to a first embodiment. The connection 60 can be implemented at several locations 59 in the fuel system 10. The first component 61 has a bore 63. The second component 62 has a nozzle 64 that is inserted into the bore 63 of the first component 61.

[0040] The connection 60 has a sealing element 65. The sealing element 65 enables a seal between the first component 61 and the second component 62. In a modified embodiment, several sealing elements 65 can also be provided for this purpose.

[0041] Furthermore, a support element 66 connected to the first component 61 is provided. The sealing element 65 is supported at least indirectly by the support element. In the Fig. In the embodiment shown in Figure 2, the sealing element 65 is directly supported on the support part 66.

[0042] The nozzle 64 has a widened section 71 at an end 70 located in the bore 63 of the first component 61. The widened section 71 is positioned between the end 70 of the nozzle 64 and the sealing element 65. In this embodiment, the widened section 71 abuts the end 70 of the nozzle 64. In the assembled state, the sealing element 65, designed as an O-ring, is compressed.

[0043] The support part 66 also encompasses a mantle-shaped outer surface 72 of the nozzle 64. Furthermore, the support part 66 is connected to the nozzle 64 at the mantle-shaped outer surface 72 of the nozzle 66. In the case of the Fig. In the embodiment shown in Figure 2, a circumferential collar 73 surrounds the mantle-shaped outer surface 72 of the nozzle 66. The collar 73 has an internal thread 74. The outer surface 72 has an external thread 75. The support part 66 is screwed with its internal thread 74 onto the external thread 75 formed on the mantle-shaped outer surface 72 of the nozzle 64.

[0044] The support part 66 comprises an inner collar 76 that surrounds the nozzle 64. The sealing element 65 is located in the Fig. In the embodiment shown in 2, the nozzle is axially supported directly on the inner collar 76 of the nozzle 64.

[0045] The support element 66 has an axial opening 77 through which a hydraulic and / or pneumatic connection is schematically illustrated. The term hydraulic and / or pneumatic connection is to be understood generally here and includes the passage of gases and / or liquids.

[0046] The support part 66 can thus be designed in the form of a nut, which enables a connection with the first component 61 and a support of the sealing element 65.

[0047] Fig. Figure 3 shows a connection 60 between the first component 61 and the second component 62 of the in Fig. Figure 1 shows a simplified, schematic sectional view of the fuel injection system 10, corresponding to a second embodiment. In this embodiment, the support part 66 is connected to the nozzle 64 via a snap connection 80. For this purpose, a bracket 81 of the support part 66 engages a projection 82 provided on the outer surface 72.

[0048] Furthermore, support discs 85, 86 are provided, which are axially supported on the support part 66. The sealing element 65 is axially supported on the support part 66 by means of the support discs 85, 86. The sealing element 65 is designed as a sealing ring. The sealing element 65, considered on its own, ensures one axial degree of freedom of the nozzle 64 relative to the first component 61.

[0049] Since the support element 66 does not come into direct contact with the medium conveyed through the connection 60, there is greater flexibility in the selection of suitable materials. Specifically, the support element 66 can be made of untreated steel, a plastic, or a fiber-reinforced plastic.

[0050] Connection 60 can be implemented in different components 100 of the fuel injection system 10. Connection 60 can be, as exemplified in Fig.As shown in Figure 1, the connection 60 is used particularly at points 59. Several components of the fuel injection system 10 are suitable as component 100. The connection 60 is particularly preferably used on a pressure regulator 30. The connection 60 can be provided, in particular, at the outlet-side connection nozzle 56. The connection 60 can also be provided, particularly preferably, on the fuel distributor 38, especially rail 38. The opening 77 can then lead into an interior space of the rail 38.

[0051] The invention is not limited to the described embodiments. QUOTES CONTAINED IN THE DESCRIPTION

[0000] 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

[0000] DE 10 2006 040 236 A1 [0002, 0003] US 2017 / 0219138 A1 [0004, 0005]

Claims

[1] Connection (60) for a hydraulic and / or pneumatic system (10), in particular a fuel system, which serves for injecting gaseous fuels, in particular hydrogen, and / or liquid fuels into combustion chambers (11) of an internal combustion engine, wherein a first component (61) of the hydraulic and / or pneumatic system (10) and a second component (62) of the hydraulic and / or pneumatic system (10) are provided, wherein the first component (61) has a bore (63), wherein the second component (62) has a nozzle (64) which is inserted into the bore (63) of the first component (61), and wherein a seal is formed between the first component and the second component (62) via at least one sealing element (65), characterized by that a support part (66) connected to the first component (61) is provided and that the sealing element (65) is supported at least indirectly on the support part (66). [2] A compound according to claim 1, characterized by that the nozzle (64) has, at an end (70) arranged in the bore (63) of the first component (61), a widened section (71) which is arranged between the end (70) of the nozzle (64) and the sealing element (65). [3] A compound according to claim 1 or 2, characterized by that the support part (66) encompasses, in particular encloses, a jacket-shaped outer side (72) of the nozzle (64), and that the support part (66) is connected to the nozzle (64) on the jacket-shaped outer side (72) of the nozzle (66). [4] Connection according to claim 3, characterized by , a) that the support part (66) is screwed onto an external thread (75) formed on the jacket-shaped outer side (72) of the nozzle (64) or b) that the support part (66) is connected to the nozzle (64) via a snap connection (80). [5] A compound according to any one of claims 1 to 4, characterized bythat the support part (66) has an inner collar (76) which encloses the nozzle (64), and that the sealing element (65) is at least indirectly axially supported on the inner collar (76) of the nozzle (64). [6] A compound according to any one of claims 1 to 5, characterized by that at least one support disc (85, 86) is provided which is axially supported on the support part (66), and that the sealing element (65) is axially supported on the support part (66) by means of the at least one support disc (85, 86). [7] A compound according to any one of claims 2 to 6, characterized by , a) that the sealing element (65) allows at least one axial degree of freedom of the nozzle (64) relative to the first component (61) and / or b) that the sealing element (65) is designed as a sealing ring. [8] A compound according to any one of claims 1 to 7, characterized bythat the support part (66) is formed at least substantially from an untempered steel, a plastic or a fiber-reinforced plastic. [9] Component (100), in particular pressure regulator (22, 30) or fuel distribution device (38), of a hydraulic and / or pneumatic system, in particular a fuel system (10), which serves for blowing gaseous fuels, in particular hydrogen, and / or for injecting liquid fuels into combustion chambers (11) of an internal combustion engine, wherein a first component (61) with a bore (63) and a second component (62) with a nozzle (64) are provided and wherein the second component (62) is connected to the first component (61) at its nozzle (64) by a connection (60) according to one of claims 1 to 8. [10] Hydraulic and / or pneumatic system, in particular fuel injection system (10), which serves for injecting gaseous fuels, in particular hydrogen, into combustion chambers (11) of an internal combustion engine, wherein at least one component (100) according to claim 9 is provided.

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