High-pressure tank

Abstract

To provide a high-pressure tank which can satisfy criteria required by suppressing an inter-layer exfoliation between a mouthpiece and a reinforcing layer.SOLUTION: A mouthpiece 3, 3A has a tip part 31, a flange part 32, a small-diameter part 33, and exfoliation prevention parts 34, 34A. In the tip part 31, a supply / discharge port 31a communicating with an internal space of a liner is opened. The flange part 32 is connected to the liner at a side opposite to the tip part 31 in an axial direction Da of the mouthpiece 3, 3A . The small-diameter part 33 becomes the smallest in diameter between the flange part 32 and the tip part 31. The exfoliation prevention parts 34, 34A are arranged between the small-diameter part 33 and an external peripheral face 31p of the tip part 31, and reduced in diameter stepwise toward the small diameter part 33 from the external peripheral face 31p of the tip part 31.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to high pressure tanks. [Background technology]

[0002] There are known inventions relating to high-pressure tanks filled with high-pressure fluid (see Patent Document 1 below). The high-pressure tank described in Patent Document 1 includes a resin liner, a nozzle, and a reinforcing layer made of fiber-reinforced resin. The nozzle has an inlet / outlet port that communicates with the internal space of the liner, and a flange that extends radially outward from the periphery of the inlet / outlet port and abuts against the liner. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-187796 A Summary of the Invention [Problem to be solved by the invention]

[0004] In order to improve the durability of the above-mentioned high-pressure tank, it is conceivable to provide a tapered section in which the diameter decreases toward the flange section at the portion of the outer circumferential surface of the nozzle where it comes into contact with the reinforcing layer. However, providing a tapered section on the nozzle may cause delamination between the nozzle and the reinforcing layer when a force is applied that presses the nozzle in the axial direction of the high-pressure tank, reducing the rigidity of the reinforcing layer and the strength of the high-pressure tank, which may result in failure to meet the required criteria.

[0005] The present disclosure provides a high-pressure tank capable of suppressing delamination between a mouthpiece and a reinforcing layer and satisfying required criteria. [Means for solving the problem]

[0006] One aspect of the present disclosure is a high-pressure tank comprising a resin liner having a hollow internal space, a cylindrical nozzle connecting the internal space of the liner to the outside, and a fiber-reinforced resin reinforcing layer covering the outer surface of the liner and joined to the outer peripheral surface of the nozzle, wherein the nozzle has a tip portion at which an inlet / outlet port connecting to the internal space of the liner opens, a flange portion connected to the liner on the axially opposite side of the nozzle from the tip portion, a small diameter portion having a smallest diameter between the flange portion and the tip portion, and a peel-off prevention portion provided between the small diameter portion and the outer peripheral surface of the tip portion, wherein the diameter of the peel-off prevention portion gradually decreases from the outer peripheral surface of the tip portion toward the small diameter portion. Effect of the Invention

[0007] According to the above-described aspect of the present disclosure, a high-pressure tank can be provided that has a nozzle having a peeling prevention portion, thereby improving the bonding strength between the outer peripheral surface of the nozzle and the reinforcing layer and suppressing interlayer peeling between the nozzle and the reinforcing layer, thereby satisfying the required criteria. [Brief description of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view illustrating an embodiment of a high-pressure tank according to the present disclosure. [Diagram 2] An enlarged cross-sectional view of the nozzle of the high-pressure tank in Figure 1. [Diagram 3] 3 is a graph showing the relationship between the displacement and the load of the high-pressure tank of FIG. 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of a high-pressure tank according to the present disclosure will be described with reference to the drawings.

[0010] 1 is a cross-sectional view showing an embodiment of a high-pressure tank according to the present disclosure. The high-pressure tank 1 of this embodiment is a high-pressure hydrogen tank that is mounted on a vehicle such as a fuel cell vehicle and is filled with hydrogen to be supplied to the fuel cell system. The high-pressure tank 1 includes a resin liner 2 having a hollow internal space, a cylindrical mouthpiece 3 that connects the internal space of the liner 2 to the outside, and a fiber-reinforced resin reinforcing layer 4 that covers the outer surface of the liner 2 and is joined to the outer circumferential surface of the mouthpiece 3.

[0011] The liner 2 generally has an elongated cylindrical shape extending in the axial direction Da. More specifically, the liner 2 has, for example, both ends in the axial direction Da that are hemispherical or dome-shaped, a body portion between the both ends that is cylindrical, and has an opening 21 at one end. More specifically, the liner 2 has, for example, as shown in Fig. 1, a cylindrical portion 22 that protrudes in the axial direction Da from one end in the axial direction Da and is inserted inside the cylindrical mouthpiece 3. The liner 2 is made of, for example, a hydrogen-impermeable resin material.

[0012] The reinforcing layer 4 is formed so as to cover the outer surface of the liner 2 and to be joined to a part of the outer surface of the nozzle 3, for example, by winding reinforcing fibers impregnated with an uncured curable resin around a part of the outer surface of the liner 2 and the nozzle 3 and curing the curable resin. Note that the reinforcing layer 4 can also be formed, for example, by winding reinforcing fibers around a part of the outer surface of the liner 2 and the nozzle 3, and then impregnating the reinforcing fibers with an uncured curable resin and curing it.

[0013] Fig. 2 is an enlarged cross-sectional view of the nozzle 3 of the high-pressure tank 1 in Fig. 1. The nozzle 3 is provided, for example, in a generally cylindrical shape coaxial with the liner 2. More specifically, the nozzle 3 has a tip portion 31 at which an inlet / outlet port 31a communicating with the internal space of the liner 2 opens, a flange portion 32 connected to the liner 2 on the opposite side of the nozzle 3 in the axial direction Da from the tip portion 31, and a small diameter portion 33 whose diameter is minimum between the flange portion 32 and the tip portion 31.

[0014] 1, the tip portion 31 is exposed from the reinforcing layer 4 that covers a part of the outer circumferential surface of the base 3. The tip portion 31 has a tip surface 31f perpendicular to the axial direction Da of the base 3, and an inlet / outlet port 31a is opened in the tip surface 31f. The tip portion 31 also has an outer circumferential surface 31p adjacent to the tip surface 31f and generally parallel to the axial direction Da of the base 3. The diameter of the tip portion 31 is smaller than the diameter of the flange portion 32, for example.

[0015] The flange portion 32 is, for example, the portion of the base 3 that has the largest diameter, and the diameter increases as it moves away from the tip portion 31 in the axial direction Da of the base 3. In the axial direction Da of the base 3, an end face 32e of the flange portion 32 facing in the opposite direction to the tip face 31f of the tip portion 31 is joined to the liner 2. The face 32f of the flange portion 32 opposite to the end face 32e joined to the liner 2 is smoothly connected to the outer circumferential surface of the liner 2 without any steps, and is covered with the reinforcing layer 4.

[0016] The small diameter portion 33 is provided, for example, at an end of the flange portion 32 on the tip portion 31 side in the axial direction Da of the nozzle 3. More specifically, for example, the flange portion 32 has a diameter that decreases toward the tip portion 31 in the axial direction Da of the nozzle 3, and is provided in a concave curved shape that is concave toward the inside of the high-pressure tank 1 in a direction intersecting the axial direction Da and radial direction Dr of the nozzle 3. The small diameter portion 33 is provided at an end of the flange portion 32 on the tip portion 31 side in the axial direction Da of the nozzle 3.

[0017] The nozzle 3 also has a peeling prevention portion 34 provided between the small diameter portion 33 and the outer circumferential surface 31p of the tip portion 31. As shown in Fig. 2, the peeling prevention portion 34 has a diameter that decreases stepwise from the outer circumferential surface 31p of the tip portion 31 to the small diameter portion 33. More specifically, the peeling prevention portion 34 provided on the nozzle 3 of the high-pressure tank 1 of the embodiment 1, the outline of which is shown by a solid line in Fig. 2, has, for example, a plurality of step portions 341, 343 and a plurality of tapered portions 342, 344, so that the diameter decreases stepwise from the outer circumferential surface 31p of the tip portion 31 to the small diameter portion 33.

[0018] More specifically, the peeling prevention portion 34 provided on the nozzle 3 of the high-pressure tank 1 of the first embodiment has, for example, a first step 341, a first tapered portion 342, a second step 343, and a second tapered portion 344 from the tip portion 31 of the nozzle 3 toward the small diameter portion 33. The first step 341 has, for example, a constant diameter smaller than the diameter of the tip portion 31 and extends in the axial direction Da of the nozzle 3. A step is formed in the radial direction Dr perpendicular to the axial direction Da of the nozzle 3 between the outer circumferential surface 31p of the tip portion 31 and the first step 341.

[0019] The first tapered portion 342 has a diameter that decreases at a constant rate, for example, from the boundary with the first tapered portion 341 to the boundary with the second tapered portion 343. The second tapered portion 343 has a constant diameter and extends in the axial direction Da of the base 3, for example, from the boundary with the first tapered portion 342 to the second tapered portion 344. In the axial direction Da of the base 3, the length of the second tapered portion 343 is, for example, shorter than the length of the first tapered portion 342.

[0020] The diameter of the second tapered portion 344 decreases from the boundary with the second step portion 343 to the small diameter portion 33 at a constant rate different from that of the first tapered portion 342. In the axial direction Da of the base 3, the length of the second tapered portion 344 is shorter than the length of the first tapered portion 342. In addition, the inclination angle of the second tapered portion 344 with respect to the axial direction Da of the base 3 is smaller than the inclination angle of the first tapered portion 342 with respect to the axial direction Da of the base 3.

[0021] 2, the peeling prevention portion 34A provided on the nozzle 3A of the high-pressure tank 1A of the embodiment 2, the outline of which is shown by a dashed line, has, for example, a plurality of tapered portions 342A, 344A, so that the diameter decreases stepwise from the outer circumferential surface 31p of the tip portion 31 toward the small diameter portion 33. More specifically, the maximum diameter of the first tapered portion 342A is smaller than the diameter of the tip portion 31, and a step is formed in the radial direction Dr perpendicular to the axial direction Da of the nozzle 3 between the outer circumferential surface 31p of the tip portion 31 and the first tapered portion 342A.

[0022] The diameter of the first tapered portion 342A decreases at a constant rate from a step formed between the outer circumferential surface 31p of the tip portion 31 and the first tapered portion 342A to the boundary with the second tapered portion 344A. The diameter of the second tapered portion 344A decreases at a constant rate different from that of the first tapered portion 342A from the boundary with the first tapered portion 342A to the small diameter portion 33. In the axial direction Da of the base 3, the length of the second tapered portion 344A is shorter than the length of the first tapered portion 342A. Also, the inclination angle of the second tapered portion 344A with respect to the axial direction Da of the base 3 is smaller than the inclination angle of the first tapered portion 342A with respect to the axial direction Da of the base 3.

[0023] Although not shown, the peeling prevention portion 34 may have, for example, one step and one tapered portion, or may have three or more step and three or more tapered portions. Also, the peeling prevention portion 34 may have, for example, only one tapered portion having a step between it and the outer circumferential surface 31p of the tip portion 31, or may have only multiple step portions. Also, the peeling prevention portion 34 may be a concave curved surface having a step between it and the outer circumferential surface 31p of the tip portion 31.

[0024] On the other hand, in Figure 2, the nozzle of the high-pressure tank of the comparative example, whose outline is shown by a two-dot chain line, has only tapered section T whose diameter decreases at a constant rate from the boundary with the outer circumferential surface 31p of tip portion 31 to small diameter section 33, and does not have peeling prevention section 34 whose diameter decreases stepwise from outer circumferential surface 31p of tip portion 31 to small diameter section 33.

[0025] Below, the functions of the first and second embodiments of the high-pressure tank according to the present disclosure will be explained based on a comparison with a comparative high-pressure tank that does not have a peeling prevention portion 34, the outline of which is indicated by a two-dot chain line in Figure 2.

[0026] The upper graph in Fig. 3 shows, with a solid line, the relationship between load and displacement of the high-pressure tank 1 of embodiment 1, in which the peeling prevention portion 34 of the nozzle 3 is shown with a solid line in Fig. 2. The lower graph in Fig. 3 shows, with a solid line, the relationship between load and displacement of the high-pressure tank 1A of embodiment 2, in which the peeling prevention portion 34 of the nozzle 3 is shown with a dashed line in Fig. 2. Note that the upper and lower graphs in Fig. 3 show, with a dashed line, the relationship between load and displacement of a high-pressure tank of a comparative example, in which the tapered portion T of the nozzle 3 is shown with a two-dot dashed line in Fig. 2, as a comparison object for the high-pressure tanks 1 and 1A of embodiments 1 and 2, respectively.

[0027] In the upper graph of Fig. 3, the relationship between the load and displacement of the high-pressure tank 1 of the first embodiment and the high-pressure tank of the comparative example, which have been subjected to zero point correction, is shown by a dashed line and a two-dot chain line, respectively. Similarly, in the lower graph of Fig. 3, the relationship between the load and displacement of the high-pressure tank 1A of the second embodiment and the high-pressure tank of the comparative example, which have been subjected to zero point correction, is shown by a dashed line and a two-dot chain line, respectively.

[0028] As described above, the high-pressure tank 1, 1A of the first and second embodiments includes a resin liner 2 having a hollow internal space, a cylindrical nozzle 3, 3A that connects the internal space of the liner 2 to the outside, and a fiber-reinforced resin reinforcing layer 4 that covers the outer surface of the liner 2 and is joined to the outer circumferential surface of the nozzle 3, 3A. The nozzle 3, 3A has a tip portion 31, a flange portion 32, a small diameter portion 33, and a peeling prevention portion 34, 34A. The tip portion 31 has an inlet / outlet port 31a that connects to the internal space of the liner 2. The flange portion 32 is connected to the liner 2 on the opposite side of the nozzle 3, 3A in the axial direction Da from the tip portion 31. The small diameter portion 33 has a minimum diameter between the flange portion 32 and the tip portion 31. The peeling prevention portions 34, 34A are provided between the small diameter portion 33 and the outer circumferential surface 31p of the tip portion 31, and the diameter decreases stepwise from the outer circumferential surface 31p of the tip portion 31 towards the small diameter portion 33.

[0029] With this configuration, when a force is applied to push the nozzle 3, 3A in the axial direction of the high-pressure tank 1, 1A, the high-pressure tank 1, 1A of the first and second embodiments can delay the timing of delamination between the nozzle 3, 3A and the reinforcing layer 4. More specifically, in the high-pressure tank of the comparative example not having the peeling prevention portion 34, 34A, delamination occurs at the displacement indicated by the triangle mark on the two-dot chain line in each graph of FIG.

[0030] In contrast, in the high-pressure tank 1 of embodiment 1, delamination occurs at the displacement indicated by the triangle mark on the dashed line in the upper graph of Fig. 3, and in the high-pressure tank 1A of embodiment 2, delamination occurs at the displacement indicated by the triangle mark on the dashed line in the lower graph of Fig. 3. Therefore, in the high-pressure tanks 1 and 1A of embodiments 1 and 2, delamination does not occur until a larger displacement occurs, compared to the high-pressure tank of the comparative example, and the timing at which delamination occurs can be delayed.

[0031] As a result, when forced displacement is applied in the static compression test of the high-pressure tank 1, 1A, a reaction force of 150 kN or more can be finally obtained, and the criteria of the static compression test can be satisfied. This is believed to be because the nozzle 3 of the high-pressure tank of the comparative example has only the tapered portion T whose diameter decreases at a constant rate, whereas the nozzle 3, 3A of the high-pressure tank 1, 1A of the first and second embodiments has the peeling prevention portion 34, 34A whose diameter decreases stepwise.

[0032] Therefore, according to the above-mentioned embodiments 1 and 2, the nozzle 3, 3A has the peeling prevention portion 34, 34A, which improves the bonding strength between the outer peripheral surface of the nozzle 3, 3A and the reinforcing layer 4, and suppresses interlayer peeling between the nozzle 3, 3A and the reinforcing layer 4, thereby providing a high-pressure tank 1, 1A that can satisfy the required criteria.

[0033] An embodiment of the high-pressure tank according to the present disclosure has been described in detail above using the drawings. However, the specific configuration is not limited to this embodiment, and even if there are design changes and the like within the scope that does not deviate from the gist of the present disclosure, they are included in the present disclosure. [Explanation of symbols]

[0034] 1. High pressure tank 1A High Pressure Tank 2 Liner 3. Base 3A Base 4 Reinforcement layer 31 Tip 31a Supply / discharge port 31f Tip surface 31p outer surface 32 Flange section 33 Small diameter section 34 Peel prevention part 34A Peel prevention part

Claims

[Claim 1] A high-pressure tank comprising: a resin liner having a hollow internal space; a cylindrical mouthpiece that connects the internal space of the liner to the outside; and a fiber-reinforced resin reinforcing layer that covers an outer surface of the liner and is joined to an outer circumferential surface of the mouthpiece, the nozzle has a tip portion at which an inlet / outlet port communicating with the internal space of the liner opens, a flange portion connected to the liner on the axially opposite side of the nozzle from the tip portion, a small diameter portion having a minimum diameter between the flange portion and the tip portion, and a peeling prevention portion provided between the small diameter portion and an outer circumferential surface of the tip portion, A high-pressure tank, characterized in that the peeling prevention portion has a diameter that gradually decreases from the outer circumferential surface of the tip portion toward the small diameter portion.

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