HYDROGEN FUEL TANK MOUNTING SYSTEM

Abstract

A hydrogen fuel tank mounting system for a vehicle comprises a first mount for mounting a first portion of the fuel tank in a fixed position and a second mount for slidably mounting a second portion of the fuel tank. In this manner, the mounting system reduces stress on fuel system components when accommodating expansion and contraction of the hydrogen fuel tank, improving durability. The fuel tank may be a dual port fuel tank, and the first and second portions may be elongated neck portions. The fixed mount may be a bracket formed in two portions with a clearance between them. A sleeve may extend through at least part of the portions of the brackets to distribute shear forces away from an interface between those portions. The provision of a slidable mounting also allows pre-assembly of the fuel tank and mounts, facilitating installation of the hydrogen fuel system.

Claims

1. A mounting system for a fuel tank, comprising: a first mount configured to attach a first portion of the fuel tank in a fixed position on a vehicle; and a second mount configured to attach a second portion of the fuel tank on the vehicle and to allow movement of at least part of the second portion relative to the vehicle.

2. The mounting system of claim 1, wherein the first mount is a bracket comprising: a body portion and a cap portion that, when attached together, form an aperture to receive the first portion of the fuel tank; at least one fastener attaching the body portion to the cap portion; and a sleeve surrounding at least part of the at least one fastener and extending through at least part of the body portion and at least part of the cap portion.

3. The mounting system of claim 2, wherein, when the body portion is attached to the cap portion, adjacent surfaces of the body portion and the cap portion are separated by a clearance.

4. The mounting system of claim 1, wherein the second mount includes: an aperture configured to receive the second portion of the fuel tank and allow sliding of the second portion through the aperture.

5. The mounting system of claim 4, comprising an insert surrounding an inner surface of the aperture, wherein the insert includes a circumferential groove configured to receive the inner surface of the aperture.

6. The mounting system of claim 1, wherein the second mount is a bracket comprising: a body portion and a cap portion that, when attached together, are arranged to receive the second portion of the fuel tank; and at least one fastener that attaches the body portion of the second mount to the cap portion of the second mount.

7. A fuel system comprising: a dual port fuel tank configured to store gaseous fuel; and the mounting system of claim 1; wherein: the first portion is a first elongated neck portion of the fuel tank; and the second portion is a second elongated neck portion of the fuel tank.

8. A vehicle comprising a fuel system according to claim 7.

9. A method of assembling a fuel system, comprising: attaching a first mount at a fixed position to a first elongated neck portion of a dual port fuel tank; attaching a second mount to a second elongated neck portion of the dual port fuel tank, wherein the second mount permits sliding motion of part of the second elongated neck portion through the second mount; and attaching the first and second mounts to a vehicle.

10. The method of claim 9, wherein the first mount is a bracket comprising: a body portion and a cap portion that, when attached together, form an aperture to receive the first portion of the fuel tank; at least one fastener attaching the body portion to the cap portion; and a sleeve surrounding at least part of the at least one fastener and extending through at least part of the body portion and at least part of the cap portion.

11. The method of claim 10, wherein, when the body portion is attached to the cap portion, adjacent surfaces of the body portion and the cap portion are separated by a clearance.

12. The method of claim 9, wherein the second mount includes: an aperture configured to receive the second portion of the fuel tank and allow sliding of the second portion through the aperture.

13. The method of claim 12, comprising: attaching an insert to an inner surface of the aperture such that the insert surrounds inner surface of the aperture; and forming a circumferential groove on the insert configured to receive the inner surface of the aperture.

14. The method of claim 9, wherein the second mount is a bracket comprising: a body portion and a cap portion that, when attached together, are arranged to receive the second portion of the fuel tank; and at least one fastener that attaches the body portion of the second mount to the cap portion of the second mount.

Description

FIGURES

[0015] Examples will now be described by way of example only, with reference to the Figures, in which:

[0016] FIG. 1 depicts a fuel system according to an example, attached to a vehicle;

[0017] FIG. 2 depicts part of the fuel system of FIG. 1;

[0018] FIGS. 3 and 4 a fuel tank and first and second mounts in the fuel system of FIG. 1;

[0019] FIG. 5 depicts a first mount in the fuel system of FIG. 1;

[0020] FIG. 6 depicts a second mount in the fuel system of FIG. 1;

[0021] FIG. 7 depicts an insert for use in the second mount of FIG. 6; and

[0022] FIG. 8 depicts a vehicle in which the fuel system of FIG. 1 is mounted.

DETAILED DESCRIPTION

[0023] With reference to FIGS. 1 and 2, a fuel system 100 is mounted in a cradle 102 and attached to a vehicle chassis 104. In this particular example, the fuel system 100 includes four hydrogen fuel tanks 106a-d arranged to supply hydrogen gas to a fuel cell 108. The fuel system 100 also includes batteries 110, 112, inverter 114, distribution unit 116.

[0024] The fuel tanks 106a-d are attached to the cradle 102 by respective first and second mounts. For example, fuel tank 106a is attached by first mount 118a and second mount 120a. FIG. 2 is a view of the cradle 102 with the fuel tanks 106a-106d removed, allowing the first mounts 118a-d for respective fuel tanks 106a-d and the second mount 120c for fuel tank 106c to be shown more clearly.

[0025] FIGS. 3 and 4 depict one of the fuel tanks 106a of the fuel system 100. In this example, the fuel tank 106a is a dual port fuel tank including first and second elongated neck portions 122, 124. The first elongated neck portion 122 is attached to the chassis 104 via the cradle 102 and the first mount 118a, while the second elongated neck portion 124 is attached to the chassis 104 via the cradle 102 and the second mount 120a.

[0026] The first and second mounts 118a, 120a each include an aperture 126, 128 configured to receive respective ones of the neck portions 122, 124 of the fuel tank 106a. The first mount 118a is configured to hold the first elongated neck portion 122 in a fixed position, while the second mount 120a is configured to allow sliding motion of the second elongated neck portion 124 through the aperture 128, along the x direction indicated in FIG. 3.

[0027] As discussed above, the hydrogen fuel tank 106a may expand while being filled. An expansion of the fuel tank 106a will cause sliding motion of the second neck portion 124 through the aperture 128 of the second mount 120a along the negative x direction, while the first neck portion 122 remains fixed in position by the first mount 118a. Such sliding motion of part of the fuel tank 106a allows the expansion of the fuel tank 106a to be accommodated within the fuel system 100 with reduced stress on the components of the fuel system 100, when compared with systems using only fixed mountings.

[0028] In a similar manner, contraction of the fuel tank 106a as the amount of hydrogen stored in the fuel tank 106a decreases causes sliding motion of the second neck portion 124 through the aperture 128 in the positive x direction, allowing the contraction to be accommodated with limited stress on the components of the fuel system 100.

[0029] FIG. 5 depicts an example first mount 118a for use in the fuel system 100 of FIG. 1, where a portion of the first mount 118a on the left of FIG. 5 is shown in section. In this particular example, the first mount 118a includes a body portion 130 and a cap portion 132, which form the aperture 126 when attached together by at least one fastener. In the example shown in FIG. 5, the body portion 130 and cap portion 132 are attached together by one or more bolts 134a that extend through at least part of the body portion 130 and at least part of the cap portion 132.

[0030] The fastener may be configured to provide a clearance 136 between adjacent surfaces of the body portion 130 and cap portion 132 when attached together. Such a clearance may reduce the effect of shear forces that would be present at the interface between the body portion 130 and cap portion 132 if their adjacent surfaces were in contact, or close contact, e.g., when clamping one end of the fuel tank to the vehicle.

[0031] Optionally, a sleeve 138 is provided around each fastener and extends into at least a part of the body portion 130 and at least a part of the cap portion 132. In this particular example, a sleeve 138, such as a hollow dowel, is provided around a part of a shaft 140 of each bolt 134a. Such a sleeve 138 can distribute any shear forces experienced by the bolt 134a along its shaft 140, e.g., due to loading of the cap portion 132 relative to the body portion 130.

[0032] In this manner, the clearance 136 and the sleeve 138 can limit localisation of stresses on at least one of the fastener, the body portion 130 and cap portion 132, improving the durability of the first mount 118a.

[0033] As shown in FIG. 5, the first mount 118a may be attached to the cradle 102 using bolts 142a, 142b or other fasteners. In other examples, the first mount 118a may be attached directly to the chassis 104 and/or to another part of a vehicle.

[0034] FIG. 6 depicts an example second mount 120a for use in the fuel system 100 of FIG. 1, where a portion of the second mount 120a on the right of FIG. 6 is shown in section. In this example, the second mount 120a includes a body portion 144 and a cap portion 146, which form the aperture 128 when attached together. In the example shown in FIG. 6, the body portion 144 and cap portion 146 are attached together by at least one fastener. In this particular example, the at least one fastener includes a bolt 148a that extends through at least part of the body portion 144 and at least part of the cap portion 146 of the second mount 120a, to clamp the body portion 144 and the cap portion 146 together.

[0035] The second mount 120a may be attached to the cradle 102, the chassis 104, or another part of a vehicle, using fasteners such as bolts 150a, 150b.

[0036] Optionally, the insert 152 is provided that surrounds an inner surface of the aperture 128. The insert 152 may be formed of a material that reduces friction when the second neck portion 124 of the fuel tank 106a slides through the aperture 128. In this particular example, the insert 152 is formed of a plastics material.

[0037] As shown in FIGS. 6 and 7, the insert 152 may include a circumferential groove 154, configured to receive the inner surface of the aperture 128. Because the inner surface of the aperture 128 is located within the groove 154, contact between the inner surfaces of the groove 154 and sides of the body portion 144 and the cap portion 146 resists motion of the insert 152 along the x direction. In this manner, the insert 152 is held in position when the second neck portion 124 is sliding through the aperture 128. The body portion 144 and the cap portion may be sized to ensure that tightening of a fastener, e.g., bolt 148a, does not substantially deform, e.g., by more than 10 microns or 100 microns, an inner opening of the insert 152 upon clamping the body portion 144 and the cap portion 146 together. In this manner, excessive clamping force is not applied to a portion of the fuel tank that is secured in the second mount 120a.

[0038] FIG. 8 shows an example of a vehicle 800 in which the fuel system may be installed. The vehicle 800 includes the fuel system 100 described above with reference to FIG. 1, located in the cradle 102 and attached to the underside of the chassis 104. As discussed above, in other examples, the fuel system 100 may be attached, directly or indirectly, to the chassis 104 or to another part of the vehicle.

[0039] Although the vehicle 800 shown in FIG. 8 is an automobile, the mounting system described above may be used to mount fuel tanks in other vehicles, including vans, trucks, coaches, buses, trucks, lorries, or any other appropriate vehicle. In some examples the mounting system described above may be used to mount fuel tanks in other applications, such as power generators, etc.

[0040] It will be understood that the invention is not limited to the examples described above and various modifications and improvements can be made without departing from the concepts described herein. Except where mutually exclusive, any of the features may be employed separately or in combination with any other features and the disclosure extends to and includes all combinations and sub-combinations of one or more features described herein.