High pressure hydrogen container

Abstract

The present invention provides a high-pressure hydrogen container that is simple in structure and easy to manufacture, can reduce manufacturing costs and ensure pressure resistance. The high-pressure hydrogen container includes: a metal cylinder for storing high-pressure hydrogen; a pair of cover parts that cover both ends of the metal cylinder; and a plurality of fastening parts that fix the metal cylinder in a state of being sandwiched between the pair of cover parts.

Description

Technical Field

[0001] The present invention relates to a high-pressure hydrogen container for storing high-pressure hydrogen. Background Art

[0002] Conventionally, a technology has been disclosed in which a high-pressure hydrogen tank having an inlet and outlet for high-pressure hydrogen provided at a dome-shaped top formed at one end of a cylindrical portion is used in a fuel cell transport vehicle (for example, see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent No. 6120017 Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, in the technology of Patent Document 1, since repeated pressure cycles of high-pressure hydrogen are expected when using the high-pressure hydrogen container mounted on a transport vehicle, a thick-walled cylindrical portion is used for the main body, and a dome-shaped portion is formed at one end of the cylindrical portion to reduce the stress level. Therefore, it is difficult to manufacture a high-pressure hydrogen container that ensures pressure resistance, and the manufacturing cost increases.

[0008] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a high-pressure hydrogen container which has a simple structure and is easy to manufacture, can reduce the manufacturing cost and ensure the pressure resistance.

[0009] Means for solving problems

[0010] The high-pressure hydrogen container of the present invention comprises:

[0011] Metal cylinders for high-pressure hydrogen storage;

[0012] a pair of cover members covering both end portions of the metal cylinder; and

[0013] A plurality of fastening members fix the metal cylinder in a state of being sandwiched between the pair of cover members.

[0014] Effects of the Invention

[0015] According to the high-pressure hydrogen container of the present invention, a plurality of fastening members fix one cover member and the other cover member of a pair of cover members in a manner that a metal cylinder is sandwiched between the two. Therefore, the high-pressure hydrogen container can be manufactured by fixing a pair of cover members using a plurality of fastening members. Therefore, it is possible to provide a high-pressure hydrogen container that has a simple structure and is easy to manufacture, can reduce manufacturing costs, and ensures pressure resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram showing a forklift according to the embodiment.

[0017] Figure 2 It is a perspective view showing the appearance of a high-pressure hydrogen tank according to the embodiment.

[0018] Figure 3 It is an exploded perspective view showing a high-pressure hydrogen tank according to the embodiment.

[0019] Figure 4 It is a schematic configuration diagram showing a high-pressure hydrogen tank according to an embodiment.

[0020] Figure 5 is from Figure 4 The direction of arrow A shows a side view of the high-pressure hydrogen container of the embodiment.

[0021] Figure 6 Yes Figure 4 Part B is enlarged to show an enlarged view.

[0022] Figure 7 It is a partially enlarged view of a modified example of the high-pressure hydrogen container 1 according to the embodiment.

[0023] Figure 8 Yes Figure 4 An enlarged view of part C is shown. DETAILED DESCRIPTION

[0024] Hereinafter, a preferred embodiment of the accumulator of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are suitable specific examples of the present invention, and therefore various technically preferred limitations are made, but unless there is a statement indicating a special limitation of the present invention in the following description, the scope of the present invention is not limited to these modes.

[0025] <Configuration of forklift 100>

[0026] Figure 1 1 is a schematic diagram showing the configuration of a forklift 100 according to the embodiment. Figure 1 The forklift 100 shown in FIG. 1 is a fuel cell type transport vehicle. The forklift 100 includes a loading and unloading device 102 at the front portion of a vehicle body 101 . The forklift 100 includes a driver's seat 103 at the center portion of the vehicle body 101 .

[0027] The forklift 100 includes a fuel cell 104 below a driver's seat 103. The fuel cell 104 includes a power generation unit 105 and a high-pressure hydrogen tank 1. The power generation unit 105 generates electricity by chemically reacting oxygen in the air with hydrogen supplied from the high-pressure hydrogen tank 1.

[0028] The forklift 100 includes a pair of front wheels 106 as driving wheels at the front of the vehicle body 101, and a pair of rear wheels 107 as steering wheels at the rear of the vehicle body 101. The pair of front wheels 106 are driven by an electric motor (not shown). Electric power is supplied to the electric motor from a power generation unit 105. The pair of rear wheels 107 are steered by a driver sitting in a driver's seat 103.

[0029] The forklift 100 is provided with a counterweight 108 at the rear of the vehicle body 101. The counterweight 108 realizes the weight adjustment of the vehicle and the weight balance in the vehicle body 101. The forklift 100 does not have a counterweight at the front of the vehicle body 101. The high-pressure hydrogen container 1 located in the center of the vehicle body 101 of the forklift 100 has the weight of the auxiliary counterweight 108. That is, the high-pressure hydrogen container 1 also serves as a part of the counterweight of the forklift 100. Therefore, the fuel cell 104 is accommodated in a casing (not shown) which is lightweight and easy to process. The casing does not serve as a part of the counterweight.

[0030] <Other transport vehicles>

[0031] As described above, the high-pressure hydrogen container 1 is used in the forklift 100. However, the high-pressure hydrogen container 1 is not limited to this application. Other transport vehicles also use the high-pressure hydrogen container 1. For example, the transport vehicle using the high-pressure hydrogen container 1 may also be a tractor used at an airport or the like.

[0032] <Configuration of high-pressure hydrogen container 1>

[0033] Figure 2 1 is a perspective view showing the appearance of a high-pressure hydrogen tank 1 according to the embodiment. Figure 3 It is an exploded perspective view showing a high-pressure hydrogen tank 1 according to the embodiment. Figure 4 1 is a schematic diagram showing the configuration of a high-pressure hydrogen tank 1 according to the embodiment. Figure 5 is from Figure 4 The direction of arrow A shows a side view of the high-pressure hydrogen container 1 according to the embodiment.

[0034] Figure 2 , Figure 3 , Figure 4 and Figure 5 The high-pressure hydrogen container 1 shown in FIG. stores high-pressure hydrogen. The high-pressure hydrogen container 1 includes a metal cylinder 2, a pair of cover members 3, and a plurality of fastening members 4. The metal cylinder 2 is used for storing high-pressure hydrogen. The pair of cover members 3 cover both ends of the metal cylinder 2 with each other. The plurality of fastening members 4 fix one cover member 3 and the other cover member 3 of the pair of cover members 3 in a manner that the metal cylinder 2 is sandwiched between the two.

[0035] <Metal Cylinder 2>

[0036] The metal cylinder 2 is a cylindrical member for storing high-pressure hydrogen with both ends open. The metal cylinder 2 is composed of a seamless metal cylindrical member in order to prevent leakage of the high-pressure hydrogen stored inside.

[0037] The metal cylinder 2 is made of, for example, low alloy steel. That is, the metal cylinder 2 is made of, for example, any one of chromium-molybdenum steel, nickel-chromium-molybdenum steel, manganese-chromium steel, manganese steel, or boron-added steel.

[0038] The decarburized layer is removed from the inner peripheral surface of the metal cylinder 2. After the decarburized layer is removed, the inner peripheral surface of the metal cylinder 2 is irradiated with a large-mass blasting ball to impart residual compressive stress to the inner surface.

[0039] It should be noted that a carbon fiber reinforced resin portion may be wound around the outer circumference of the metal cylinder 2. The carbon fiber reinforced resin portion is provided to ensure the pressure resistance, i.e., mechanical strength, required for the metal cylinder 2. The carbon fiber reinforced resin portion is a composite material in which carbon fiber is used as a reinforcing material and impregnated with resin to increase strength, such as PAN-based carbon fiber or PITCH-based carbon fiber.

[0040] <Cover part 3>

[0041] The cover parts 3 are respectively covered and installed on the two ends of the metal cylinder 2 to seal the metal cylinder 2. A pair of cover parts 3 each use a plate-like body with a square front and back shape. A pair of cover parts 3 are installed with their upper, lower, left and right sides in parallel to facilitate installation or stacking. It should be noted that the shape of the cover parts 3 is not limited to the above-mentioned structure and can be appropriately designed and changed. At least one cover part 3 is provided with an unillustrated valve connected to an unillustrated hydrogen through hole for sealing or releasing high-pressure hydrogen. The pair of cover parts 3 is made of the same metal as the metal cylinder 2.

[0042] Each of the pair of cover members 3 is formed with a plurality of through holes 3a through which the plurality of fastening members 4 are inserted. It should be noted that a recessed portion for accommodating the nuts 5 of the fastening members 4 may be formed in the through holes 3a of the cover members 3. Here, since there is no recessed portion, the nuts 5 of the fastening members 4 protrude to the outside of the cover members 3.

[0043] <Fasteners 4>

[0044] Bolts are used for the fastening components 4. The bolts used in the fastening components 4 are long screws with nuts 5 screwed to both ends. Therefore, each of the plurality of fastening components 4 is inserted into a through hole 3a formed in one cover component 3 and a through hole 3a formed in another cover component 3, and protrudes to the outside of the two cover components 3. In addition, the nuts 5 are screwed to both ends of the fastening components 4 protruding to the outside of the two cover components 3. It should be noted that the fastening components 4 may also use bolts with a head at one end and only the other end screwed to the nut 5.

[0045] The plurality of fastening members 4 inserted into the through hole 3a formed on one cover member 3 and the through hole 3a formed on the other cover member 3 are arranged in such a manner that the extending direction, i.e., the length direction, is parallel to the central axis O of the metal cylinder 2. The plurality of fastening members 4 are scattered on the outer circumference of the metal cylinder 2 and surround the outer circumference of the metal cylinder 2. In detail, the plurality of fastening members 4 are scattered at multiple locations on the same circumference at constant and equal intervals for fixing. Furthermore, the metal cylinder 2 and the plurality of fastening members 4 surrounding the outer circumference of the metal cylinder 2 constitute concentric circles centered on the central axis O of the metal cylinder 2. In other words, the plurality of fastening members 4 are arranged on a circle centered on the central axis O of the metal cylinder 2. A gap S is formed between the metal cylinder 2 and the plurality of fastening members 4 surrounding the outer circumference of the metal cylinder 2 to separate the metal cylinder 2 from the plurality of fastening members 4. It should be noted that the arrangement of the plurality of fastening members 4 is not limited to the above-mentioned configuration, and can be appropriately changed according to the design.

[0046] Both ends of the plurality of fastening members 4 are screwed and fixed to the outer sides of the two cover members 3. It should be noted that the fastening members 4 can also be screwed and fixed by inserting a tool such as a wrench between the recessed portion of the cover member 3 and the nut 5. In addition, the fastening members 4 can also have an insertion hole in the head for inserting a tool such as a hexagonal wrench for screwing and fixing.

[0047] <Details of Part B of High-Pressure Hydrogen Container 1>

[0048] Figure 6 Yes Figure 4 The enlarged view of part B is shown. Figure 4 and Figure 6 As shown, the high-pressure hydrogen container 1 has two fitting structures 6 for fitting the metal cylinder 2 into the pair of cover members 3 , respectively.

[0049] like Figure 6 As shown, each of the two fitting structures 6 has a convex portion 6a and a groove portion 6b. The convex portion 6a has an outer periphery that fits with the inner periphery of the metal cylinder 2 on the metal cylinder 2 side of each of the pair of cover members 3. The groove portion 6b is recessed in the direction opposite to the protruding direction of the convex portion 6a on the outer periphery of the convex portion 6a on the metal cylinder 2 side of each of the pair of cover members 3 so that the end of the metal cylinder 2 can be inserted. It should be noted that the fitting structure 6 can also be fitted in other shapes.

[0050] A first sealing portion 7 is provided to seal the side circumference of the protrusion 6a with the inner circumference of the metal cylinder 2. The first sealing portion 7 includes a first sealing groove 7a formed around the entire side circumference of the protrusion 6a, a first O-ring 7b disposed in the first sealing groove 7a, and a support ring 7c disposed on the cover member 3 side relative to the first O-ring 7b in the first sealing groove 7a. The first sealing groove 7a is configured so that a retaining ring 7d is screwed to the protrusion of the cover member 3 provided with the protrusion 6a by a screw 7e. The outer diameter of the retaining ring 7d is formed larger than the bottom diameter of the first sealing groove 7a. Thus, the first sealing groove 7a is formed as an annular groove with a smaller outer circumference size of the protrusion 6a between the protrusion of the cover member 3 and the retaining ring 7d. The first O-ring 7b and the support ring 7c are configured so as not to fall off from the first sealing groove 7a formed as an annular groove by passing through the retaining ring 7d. It should be noted that the first sealing portion 7 may not have the support ring 7c, and may have a second support ring disposed on the metal cylinder 2 side compared to the first O-ring 7b in the first sealing groove 7a. The side circumferential surface of the convex portion 6a and the inner circumferential surface of the metal cylinder 2 are parallel to the central axis O of the metal cylinder 2. It should be noted that the retaining ring 7d may also be made of a metal material different from that of the cover member 3.

[0051] A second sealing portion 8 is provided to seal the bottom of the groove portion 6b and the end surface of the metal cylinder 2 that is embedded in the groove portion 6b and abuts against the bottom of the groove portion 6b. The second sealing portion 8 includes a second sealing groove 8a formed around the entire circumference of the end surface of the metal cylinder 2 and a second O-ring 8b disposed in the second sealing groove 8a. The end surface of the metal cylinder 2 and the bottom surface of the groove portion 6b are planes that are orthogonal to the central axis O of the metal cylinder 2.

[0052] It should be noted that the first sealing portion 7 and the second sealing portion 8 only need to be able to perform a sealing function, and are not limited to the above-mentioned configurations, and well-known techniques may be used.

[0053] A leakage port 9 penetrating from the inside to the outside is provided between the first seal 7 and the second seal 8 in the metal cylinder 2. A hydrogen sensor 10 is provided at the outlet of the leakage port 9. The hydrogen sensor 10 monitors the leakage of hydrogen before the first seal 7 is broken and the second seal 8 is broken. In addition, sometimes even if the first seal 7 or the second seal 8 is not broken, hydrogen leakage occurs due to the deterioration of the material constituting the seal. Among them, the leakage port 9 is formed on at least one cover member 3. It should be noted that the leakage port 9 is formed to open on the surface of the metal cylinder 2 located on the cover member 3 side compared with the first seal 7, that is, on the surface of the cover member 3 on the metal cylinder 2 side, located between the part where the first seal 7 abuts and the part where the second seal 8 abuts. In addition, the leakage port 9 is located on the inner side of the hydrogen storage compared with the second seal 8, so that hydrogen does not reach the groove 6b where stress is easily concentrated and the part where the fastening member 4 is fastened. Therefore, the strength reduction caused by hydrogen does not affect the stress concentration part, so the reliability of the strength of the high-pressure hydrogen container 1 is improved.

[0054] like Figure 6 As shown, the leakage port 9 is connected to the outside of the high-pressure hydrogen container 1. The gas passing through the leakage port 9 is configured to be guided to the hydrogen sensor 10 provided outside the high-pressure hydrogen container 1. The hydrogen sensor 10 detects hydrogen in the gas guided through the leakage port 9. The high-pressure hydrogen container 1 may also be configured to issue a warning when the hydrogen sensor 10 detects that the content of hydrogen contained in the gas is greater than a predetermined value.

[0055] In addition, the hydrogen sensor 10 may also always monitor the gas guided through the leakage port 9. Hydrogen permeates through the material constituting the first O-ring 7b, so that the first sealing portion 7 of the high-pressure hydrogen container 1 always causes a predetermined amount of hydrogen to leak through the leakage port 9. The hydrogen sensor 10 can detect a change in the amount of hydrogen contained in the gas by always monitoring the gas guided through the leakage port 9, and thus can detect hydrogen leakage caused by abnormalities such as deterioration or rupture of the first sealing portion 7 based on the change.

[0056] In addition, by always monitoring with the hydrogen sensor 10, it is also possible to determine whether the operation of the hydrogen sensor 10 itself is normal. That is, if the hydrogen sensor 10 is normal, since it always continues to detect hydrogen that has passed through the first sealing portion 7, when the hydrogen sensor 10 does not detect hydrogen, it can be determined that the hydrogen sensor 10 itself is not operating normally. Therefore, by giving a warning even when the hydrogen sensor 10 does not detect hydrogen, it is also possible to detect abnormalities in the hydrogen sensor 10 itself, thereby improving the reliability of the high-pressure hydrogen container 1.

[0057] The hydrogen sensor 10 may also include a notification device 50 for notifying of changes in the amount of hydrogen in the gas guided through the leak port 9. In addition, the notification device 50 may also notify that the hydrogen sensor 10 does not detect hydrogen, that is, the amount of hydrogen contained in the gas has substantially become 0. The notification device 50 may also be implemented by means such as an external display or a warning light.

[0058] Figure 7 1 is a partially enlarged view of a modified example of the high-pressure hydrogen container 1 of the embodiment. Figure 7 In the modified example of the high-pressure hydrogen container 1 shown in FIG, the shape of the cover member 3 is changed, and the end of the metal cylinder 2 is not fitted into the groove portion 6b but abuts against the flange portion 6c. For the cover member 13 of the modified example, if the strength of the flange portion 6c can be ensured, the same strength as the cover member 3 can be ensured, and hydrogen leakage from the inside can be suppressed.

[0059] <Details of the C portion of the high-pressure hydrogen container 1>

[0060] Figure 8 Yes Figure 4 The enlarged view of part C is shown. Figure 8 As shown, the high-pressure hydrogen container 1 has a common passing position P, and the common passing position P has the shortest distance common to the following paths: when reaching the outside from the inside of the metal cylinder 2 in the metal cylinder 2 and the pair of cover parts 3, the path to the outside in any one of the pair of cover parts 3 and the path to the position where the fastening part 4 closest to the metal cylinder 2 among the plurality of fastening parts 4 is inserted in the cover part 3. The minimum thickness from the common passing position P to the outside in the cover part 3 is set to t [mm]. The distance between the common passing position P and the position where the fastening part 4 closest to the metal cylinder 2 among the plurality of fastening parts 4 is inserted in the cover part 3 is L0 [mm]. At this time, L0>t is satisfied. Here, the reason for setting L0 as the position where the fastening part 4 closest to the metal cylinder 2 is inserted in any one of the pair of cover parts 3 is that the situation where the plurality of fastening parts 4 are not scattered on the same circle is considered at the same time.

[0061] <Effects of implementation>

[0062] According to the embodiment, the high-pressure hydrogen container 1 includes a metal cylinder 2 for storing high-pressure hydrogen. The high-pressure hydrogen container 1 includes a pair of cover members 3 that respectively cover both ends of the metal cylinder 2. The high-pressure hydrogen container 1 includes a plurality of fastening members 4 that fix one cover member 3 and the other cover member 3 of the pair of cover members 3 so as to sandwich the metal cylinder 2 therebetween.

[0063] According to this configuration, the plurality of fastening members 4 fix one cover member 3 and the other cover member 3 of the pair of cover members 3 in a manner that the metal cylinder 2 is sandwiched therebetween. Therefore, the high-pressure hydrogen container 1 can be manufactured by fixing the pair of cover members 3 with the plurality of fastening members 4. Therefore, it is possible to provide a high-pressure hydrogen container 1 that has a simple configuration, is easy to manufacture, can reduce manufacturing costs, and can ensure pressure resistance.

[0064] According to an embodiment, bolts are used to fasten the component 4 .

[0065] According to this configuration, the high-pressure hydrogen container 1 can be manufactured by fixing the pair of cover members 3 with the plurality of fastening members 4 using bolts.

[0066] According to the embodiment, each of the pair of cover members 3 is formed with a plurality of through holes 3a through which the plurality of fastening members 4 are inserted. The plurality of fastening members 4 are inserted into the through holes 3a formed in one cover member 3 and the through holes 3a formed in the other cover member 3, respectively.

[0067] According to this configuration, each of the plurality of fastening members 4 can be inserted into the through hole 3 a formed in one cover member 3 and the through hole 3 a formed in the other cover member 3 , respectively. The high-pressure hydrogen container 1 is manufactured by fixing a pair of cover members 3 with the plurality of fastening members 4 .

[0068] According to the embodiment, the plurality of fastening members 4 inserted into the through hole 3 a formed in one cover member 3 and the through hole 3 a formed in the other cover member 3 are arranged so that their extending directions, ie, their longitudinal directions, are parallel to the central axis O of the metal cylinder 2 .

[0069] According to this configuration, the direction of the clamping force of each of the plurality of fastening members 4 for clamping and fixing the metal cylinder 2 is parallel to the central axis O of the metal cylinder 2 , and the clamping force does not cause torsion, thereby improving the durability of the high-pressure hydrogen container 1 .

[0070] According to the embodiment, the plurality of fastening members 4 are dispersed on the outer circumference of the metal cylinder 2 and surround the outer circumference of the metal cylinder 2 .

[0071] According to this configuration, the plurality of fastening members 4 that are dispersed on the outer circumference of the metal cylinder 2 and surround the outer circumference of the metal cylinder 2 are respectively dispersed on the outer circumference of the metal cylinder 2, and can exert a clamping force that clamps and fixes the metal cylinder 2. As a result, the clamping force is well-balanced on the outer circumference of the metal cylinder 2, and the durability of the high-pressure hydrogen container 1 can be improved.

[0072] According to the embodiment, the plurality of fastening members 4 are spread at the same intervals on the same circumference. The metal cylinder 2 and the plurality of fastening members 4 surrounding the outer circumference of the metal cylinder 2 form concentric circles centered on the central axis O of the metal cylinder 2 .

[0073] According to this configuration, the plurality of fastening members 4 constituting concentric circles centered on the central axis O of the metal cylinder 2 are dispersed on the outer circumference of the metal cylinder 2 at equal distances from the metal cylinder 2, and can exert a clamping force to clamp and fix the metal cylinder 2. As a result, the clamping force can exert equal effects on the metal cylinder 2 at the outer circumference of the metal cylinder 2 and these effects can be well balanced, thereby improving the durability of the high-pressure hydrogen container 1.

[0074] According to the embodiment, a gap S is formed between the metal cylinder 2 and the plurality of fastening members 4 surrounding the outer circumference of the metal cylinder 2 to separate the metal cylinder 2 and the plurality of fastening members 4 .

[0075] According to this structure, hydrogen permeates at the metal cylinder 2 that is in direct contact with the stored high-pressure hydrogen. However, at the multiple fastening parts 4 separated by the gap S, the hydrogen seeping from the metal cylinder 2 does not diffuse and permeate from the gap S. Therefore, the high-pressure hydrogen container 1 does not suffer from hydrogen degradation of the multiple fastening parts 4, and the durability of the multiple fastening parts 4 can be improved. In addition, the gap S exists between the metal cylinder 2 and the multiple fastening parts 4, so that even if the metal cylinder 2 is deformed in the circumferential direction due to the stored high-pressure hydrogen, its deformation stress will not be transmitted to the multiple fastening parts 4. In addition, by configuring the fastening parts 4 to be separated by the gap S, the part of the cover part 3 that receives the load from the fastening parts 4 is also away from the part where the metal cylinder 2 and the cover part 3 are embedded, so that the stress generating part is not easily affected by hydrogen embrittlement, and the reliability of the strength is improved.

[0076] According to the embodiment, the high-pressure hydrogen container 1 has two fitting structures 6 for fitting the metal cylinder 2 into the pair of cover members 3 , respectively.

[0077] According to this configuration, the metal cylinder 2 and the pair of lid members 3 are fitted together by the two fitting structures 6, thereby ensuring sealing between the metal cylinder 2 and the pair of lid members 3. Thus, the high-pressure hydrogen container 1 can be configured as a container that prevents the stored high-pressure hydrogen from leaking.

[0078] According to the embodiment, each of the two fitting structures 6 has a convex portion 6a having an outer periphery fitted with the inner periphery of the metal cylinder 2 on the metal cylinder 2 side of each of the pair of cover members 3. In addition, each of the pair of cover members 3 has a groove portion 6b, which is recessed in the direction opposite to the protruding direction of the convex portion 6a on the outer periphery of the metal cylinder 2 side so that the end of the metal cylinder 2 can be inserted.

[0079] According to this configuration, the metal cylinder 2 and the pair of cover members 3 are fitted together by the two fitting structures 6 having the protrusion 6 a and the groove 6 b , respectively, so that sealing can be ensured between the metal cylinder 2 and the pair of cover members 3 .

[0080] According to the embodiment, the first sealing portion 7 is provided to seal the side peripheral surface of the convex portion 6 a and the inner peripheral surface of the metal cylinder 2 .

[0081] According to this configuration, the first seal portion 7 seals the side peripheral surface of the convex portion 6 a and the inner peripheral surface of the metal cylinder 2 , and can ensure sealing properties between the metal cylinder 2 and the pair of cover members 3 .

[0082] According to the embodiment, the first sealing portion 7 has: a first sealing groove 7a formed around the entire circumference of the side circumference of the protrusion 6a; a first O-ring 7b arranged in the first sealing groove 7a; and a support ring 7c arranged on the cover member 3 side compared to the first O-ring 7b in the first sealing groove 7a.

[0083] According to this configuration, the first sealing portion 7 using the first O-ring 7b and the support ring 7c arranged in the first sealing groove 7a seals the side circumferential surface of the protrusion 6a and the inner circumferential surface of the metal cylinder 2, thereby ensuring sealing between the metal cylinder 2 and each of the pair of cover members 3.

[0084] According to the embodiment, the second seal portion 8 is provided to seal the bottom of the groove portion 6 b with the end surface of the metal cylinder 2 that is fitted into the groove portion 6 b and abuts against the bottom of the groove portion 6 b.

[0085] According to this configuration, the second sealing portion 8 seals the bottom of the groove portion 6b with the end surface of the metal cylinder 2, and can ensure sealing between the metal cylinder 2 and each of the pair of cover members 3. Moreover, the second sealing portion 8 functions as a top cover seal, and its sealing surface is different from the first sealing portion 7 that functions as an inner hole seal. Thus, the second sealing portion 8 is not affected by the airtightness of the first sealing portion 7 by making the sealing surface different from the first sealing portion 7, so that the sealing of the high-pressure hydrogen container 1 can be further ensured on the basis of the first sealing portion 7, and the hydrogen leakage prevention performance of the high-pressure hydrogen container 1 can be further improved. In addition, the first sealing portion 7 and the second sealing portion 8 are provided together in the same interlocking structure 6 having different surfaces provided with the two, and can be efficiently configured.

[0086] According to the embodiment, the second seal portion 8 includes a second seal groove 8 a formed around the entire circumference of the end surface of the metal cylinder 2 , and a second O-ring 8 b disposed in the second seal groove 8 a .

[0087] According to this configuration, the second seal portion 8 using the second O-ring 8b disposed in the second seal groove 8a seals the bottom of the groove portion 6b and the end surface of the metal cylinder 2, and thus the seal can be ensured between the metal cylinder 2 and each of the pair of cover members 3. In addition, since the second O-ring 8b is not disposed at the bottom of the groove portion 6b of the cover member 3 but is disposed in the second seal groove 8a formed on the end surface of the metal cylinder 2, it is easy to form the second seal groove 8a, and it is easy to dispose the second O-ring 8b and manufacture the second seal portion 8.

[0088] According to the embodiment, a leakage port 9 penetrating from the inside to the outside is provided between the first sealing portion 7 and the second sealing portion 8 in the metal cylinder 2 .

[0089] According to this configuration, the stored hydrogen flows out from the leakage port 9, so that the rupture or degradation of the first sealing portion 7 can be detected before the rupture or degradation of the second sealing portion 8. Thus, the rupture or degradation of the first sealing portion 7 can be detected before the hydrogen leakage of the high-pressure hydrogen container 1 caused by the rupture or degradation of the second sealing portion 8, and the hydrogen leakage of the high-pressure hydrogen container 1 can be prevented.

[0090] According to the embodiment, a hydrogen sensor 10 is further provided for detecting hydrogen contained in the gas passing through the leakage port 9. In addition, the hydrogen sensor 10 always monitors the amount of hydrogen contained in the gas passing through the leakage port 9, and notifies when the amount of hydrogen contained in the gas is greater than a predetermined value. In addition, the hydrogen sensor 10 notifies when the amount of hydrogen contained in the gas becomes 0. By configuring in this way, the high-pressure hydrogen container 1 can reliably detect hydrogen leakage caused by rupture or degradation of the first sealing portion 7, and can determine whether the hydrogen sensor 10 is operating normally. As a result, the reliability of hydrogen leakage detection is improved, and the reliability of the high-pressure hydrogen container 1 is improved.

[0091] According to the embodiment, the high-pressure hydrogen container 1 has a common passing position P, and the common passing position P has the shortest distance common to the following paths: when reaching the outside from the metal cylinder 2 and the inside of the metal cylinder 2 of the pair of cover members 3, the path to the outside in any one of the pair of cover members 3 and the path to the position where the fastening member 4 closest to the metal cylinder 2 among the plurality of fastening members 4 is inserted into the cover member 3. The minimum thickness from the common passing position P to the outside in the cover member 3 is t [mm]. The distance between the common passing position P and the position where the fastening member 4 closest to the metal cylinder 2 among the plurality of fastening members 4 is inserted into the cover member 3 is L0 [mm]. At this time, L0>t is satisfied.

[0092] According to this configuration, hydrogen permeates the metal cylinder 2 and the pair of cover members 3 that are in direct contact with the stored high-pressure hydrogen. However, when L0>t is satisfied, at the fastening member 4, before hydrogen permeates inside and outside the cover member 3, it does not permeate through the cover member 3 to the fastening member 4. Therefore, the high-pressure hydrogen container 1 can avoid hydrogen degradation at the plurality of fastening members 4 before hydrogen degradation occurs at the cover member 3, and is not easily damaged.

[0093] According to the embodiment, a pair of cover members 3 each use a plate-like body having a square front and back shape.

[0094] According to this configuration, the manufacturer can perform machining on each of the pair of cover members 3 by lathe machining instead of milling machining. This can reduce machining costs and facilitate the manufacture of the high-pressure hydrogen container 1.

[0095] According to the embodiment, the high-pressure hydrogen tank 1 also serves as a part of the counterweight of the transportation vehicle.

[0096] According to this structure, the weight of the high-pressure hydrogen container 1 is increased due to the metal cylinder 2, the pair of cover members 3 and the plurality of fastening members 4. Therefore, the total amount of the counterweight carried by the transport vehicle can be reduced, and the number of parts of the transport vehicle can be reduced. As a result, the manufacturing cost of the transport vehicle can be reduced.

[0097] Description of Reference Numerals

[0098] 1 high pressure hydrogen container, 2 metal cylinder, 3 cover member, 3a through hole, 4 fastening member, 5 nut, 6 fitting structure, 6a convex portion, 6b groove portion, 6c flange portion, 7 first sealing portion, 7a first sealing groove, 7b first O-ring, 7c support ring, 7d retaining ring, 7e screw, 8 second sealing portion, 8a second sealing groove, 8b second O-ring, 9 leakage port, 10 hydrogen sensor, 13 cover member, 50 alarm device, 100 forklift, 101 vehicle body, 102 loading and unloading device, 103 driver's seat, 104 fuel cell, 105 power generation unit, 106 front wheel, 107 rear wheel, 108 counterweight.

Claims

1. A high-pressure hydrogen container, comprising: Metal cylinders for high-pressure hydrogen storage; a pair of cover members covering both ends of the metal cylinder; and a plurality of fastening members for fixing the metal cylinder in a state of being sandwiched between the pair of cover members, The high-pressure hydrogen container has two fitting structures for fitting the metal cylinder into the pair of cover members, respectively. Each of the pair of cover members has a convex portion having an outer periphery fitted with the inner periphery of the metal cylinder on the side of the metal cylinder, A first sealing portion is provided for sealing the side circumferential surface of the convex portion with the inner circumferential surface of the metal cylinder, and a second sealing portion is provided for sealing the pair of cover members with the end surfaces of the metal cylinder respectively abutting against the pair of cover members. A leakage port penetrating from the inside to the outside is provided between the first sealing portion and the second sealing portion in the metal cylinder.

2. The high-pressure hydrogen container according to claim 1, wherein: Bolts are used for the plurality of fastening members.

3. The high-pressure hydrogen container according to claim 2, wherein: A plurality of through holes through which the plurality of fastening members are inserted are respectively formed in each of the pair of cover members. Each of the plurality of fastening members is inserted into the plurality of through holes formed in each of the pair of cover members.

4. The high-pressure hydrogen container according to claim 3, wherein: Each of the plurality of fastening members is arranged such that a longitudinal direction thereof is parallel to a central axis of the metal cylinder.

5. The high-pressure hydrogen container according to claim 1, wherein: The plurality of fastening members are spread over the outer circumference of the metal cylinder and surround the outer circumference of the metal cylinder.

6. The high-pressure hydrogen container according to claim 2, wherein: The plurality of fastening members are spread over the outer circumference of the metal cylinder and surround the outer circumference of the metal cylinder.

7. The high-pressure hydrogen container according to claim 3, wherein: The plurality of fastening members are spread over the outer circumference of the metal cylinder and surround the outer circumference of the metal cylinder.

8. The high-pressure hydrogen container according to claim 4, wherein: The plurality of fastening members are spread over the outer circumference of the metal cylinder and surround the outer circumference of the metal cylinder.

9. The high-pressure hydrogen container according to any one of claims 5 to 8, wherein: The plurality of fastening components are distributed on the same circumference at the same intervals, The metal cylinder and the plurality of fastening members surrounding the outer circumference of the metal cylinder form concentric circles centered on the central axis of the metal cylinder.

10. The high-pressure hydrogen container according to any one of claims 5 to 8, wherein: A gap is formed between the metal cylinder and the plurality of fastening members surrounding the outer circumference of the metal cylinder to separate the metal cylinder from the plurality of fastening members.

11. The high-pressure hydrogen container according to claim 9, wherein: A gap is formed between the metal cylinder and the plurality of fastening members surrounding the outer circumference of the metal cylinder to separate the metal cylinder from the plurality of fastening members.

12. The high-pressure hydrogen container according to any one of claims 1 to 8, wherein: The first sealing portion comprises: A first sealing groove formed around the entire circumference of the side surface of the convex portion; A first O-ring disposed in the first sealing groove; and A backup ring is arranged on the pair of cover members side relative to the first O-ring in the first seal groove.

13. The high-pressure hydrogen container according to claim 9, wherein: The first sealing portion comprises: A first sealing groove formed around the entire circumference of the side surface of the convex portion; A first O-ring disposed in the first sealing groove; and A backup ring is arranged on the pair of cover members side relative to the first O-ring in the first seal groove.

14. The high-pressure hydrogen container according to claim 10, wherein: The first sealing portion comprises: A first sealing groove formed around the entire circumference of the side surface of the convex portion; A first O-ring disposed in the first sealing groove; and A backup ring is arranged on the pair of cover members side relative to the first O-ring in the first seal groove.

15. The high-pressure hydrogen container according to claim 11, wherein: The first sealing portion comprises: A first sealing groove formed around the entire circumference of the side surface of the convex portion; A first O-ring disposed in the first sealing groove; and A backup ring is arranged on the pair of cover members side relative to the first O-ring in the first seal groove.

16. The high-pressure hydrogen container according to claim 12, wherein: The second sealing portion has: a second sealing groove formed around the entire circumference of the end surface of the metal cylinder; and The second O-ring is disposed in the second sealing groove.

17. The high-pressure hydrogen container according to claim 13, wherein: The second sealing portion has: a second sealing groove formed around the entire circumference of the end surface of the metal cylinder; and The second O-ring is disposed in the second sealing groove.

18. The high-pressure hydrogen container according to claim 14, wherein: The second sealing portion has: a second sealing groove formed around the entire circumference of the end surface of the metal cylinder; and The second O-ring is disposed in the second sealing groove.

19. The high-pressure hydrogen container according to claim 15, wherein: The second sealing portion has: a second sealing groove formed around the entire circumference of the end surface of the metal cylinder; and The second O-ring is disposed in the second sealing groove. 20 . The high-pressure hydrogen container according to claim 16 , further comprising a hydrogen sensor for detecting hydrogen contained in the gas passing through the leak port. 21 . The high-pressure hydrogen container according to claim 17 , further comprising a hydrogen sensor for detecting hydrogen contained in the gas passing through the leak port. 22 . The high-pressure hydrogen container according to claim 18 , further comprising a hydrogen sensor for detecting hydrogen contained in the gas passing through the leak port. 23 . The high-pressure hydrogen container according to claim 19 , further comprising a hydrogen sensor for detecting hydrogen contained in the gas passing through the leak port.

24. The high-pressure hydrogen container according to claim 20, wherein: The hydrogen sensor constantly monitors the amount of hydrogen contained in the gas passing through the leak port, and issues a notification when the amount of hydrogen contained in the gas passing through the leak port is equal to or greater than a predetermined value.

25. The high-pressure hydrogen container according to claim 21, wherein: The hydrogen sensor constantly monitors the amount of hydrogen contained in the gas passing through the leak port, and issues a notification when the amount of hydrogen contained in the gas passing through the leak port is equal to or greater than a predetermined value.

26. The high-pressure hydrogen container according to claim 22, wherein: The hydrogen sensor constantly monitors the amount of hydrogen contained in the gas passing through the leak port, and issues a notification when the amount of hydrogen contained in the gas passing through the leak port is equal to or greater than a predetermined value.

27. The high-pressure hydrogen container according to claim 23, wherein: The hydrogen sensor constantly monitors the amount of hydrogen contained in the gas passing through the leak port, and issues a notification when the amount of hydrogen contained in the gas passing through the leak port is equal to or greater than a predetermined value.

28. The high-pressure hydrogen container according to claim 20, wherein: The hydrogen sensor reports when the amount of hydrogen included in the gas passing through the leak port becomes zero.

29. The high-pressure hydrogen container according to claim 21, wherein: The hydrogen sensor reports when the amount of hydrogen included in the gas passing through the leak port becomes zero.

30. The high pressure hydrogen container according to claim 22, wherein: The hydrogen sensor reports when the amount of hydrogen included in the gas passing through the leak port becomes zero.

31. The high-pressure hydrogen container according to claim 23, wherein: The hydrogen sensor reports when the amount of hydrogen included in the gas passing through the leak port becomes zero.

32. The high pressure hydrogen container according to claim 24, wherein: The hydrogen sensor reports when the amount of hydrogen included in the gas passing through the leak port becomes zero.

33. The high pressure hydrogen container according to claim 25, wherein: The hydrogen sensor reports when the amount of hydrogen included in the gas passing through the leak port becomes zero.

34. The high pressure hydrogen container according to claim 26, wherein: The hydrogen sensor reports when the amount of hydrogen included in the gas passing through the leak port becomes zero.

35. The high pressure hydrogen container according to claim 27, wherein: The hydrogen sensor reports when the amount of hydrogen included in the gas passing through the leak port becomes zero.

36. The high pressure hydrogen container according to claim 12, wherein: Each of the pair of cover members further includes a groove portion located on the outer peripheral side of the convex portion. The groove portion is recessed in a direction opposite to a protruding direction of the convex portion so that the metal cylinder can be inserted therein.

37. The high pressure hydrogen container according to claim 17, wherein: Each of the pair of cover members further includes a groove portion located on the outer peripheral side of the convex portion. The groove portion is recessed in a direction opposite to a protruding direction of the convex portion so that the metal cylinder can be inserted therein.

38. The high pressure hydrogen container according to claim 22, wherein: Each of the pair of cover members further includes a groove portion located on the outer peripheral side of the convex portion. The groove portion is recessed in a direction opposite to a protruding direction of the convex portion so that the metal cylinder can be inserted therein.

39. The high pressure hydrogen container according to claim 27, wherein: Each of the pair of cover members further includes a groove portion located on the outer peripheral side of the convex portion. The groove portion is recessed in a direction opposite to a protruding direction of the convex portion so that the metal cylinder can be inserted therein.

40. The high pressure hydrogen container according to claim 28, wherein: Each of the pair of cover members further includes a groove portion located on the outer peripheral side of the convex portion. The groove portion is recessed in a direction opposite to a protruding direction of the convex portion so that the metal cylinder can be inserted therein.

41. The high-pressure hydrogen container according to any one of claims 1 to 8, wherein: There is a common passing position, and the common passing position has the shortest distance common to the following paths, and the path is: When reaching the outside from the inside of the metal cylinder and the pair of cover parts, a path to reach the outside in any one of the pair of cover parts, and a path to reach a position where the fastening part closest to the metal cylinder among the plurality of fastening parts is inserted into the cover part, Here, when the minimum thickness from the common via position in the cover member to the outside is t [mm], When the distance between the common path position and the position where the fastening member closest to the metal cylinder among the plurality of fastening members is inserted into the cover member is L0 [mm], Satisfies L0>t.

42. The high-pressure hydrogen container according to any one of claims 1 to 8, wherein: Each of the pair of cover members is a plate-like body having a square front and back shape.

43. The high-pressure hydrogen container according to any one of claims 1 to 8, wherein: The high-pressure hydrogen tank also serves as a part of the counterweight of the transport vehicle.

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