Extrusion die for manufacturing hollow shape material and hollow shape material

Abstract

To provide an extrusion die that can form a hollow shape material having sufficient strength.SOLUTION: An extrusion die for manufacturing a hollow shape material manufactures a hollow shape material 1 in which a dimension between both side surfaces 13 is longer than a dimension between an upper surface 11 and a lower surface 12 on an outer peripheral surface 10 and which has a hollow part 15 extending in a length direction to a side lower than an intermediate position in a vertical direction. A mandrel 41 for forming an inner peripheral surface of the hollow part 15 is oppositely arranged on a die hole 51 for forming the outer peripheral surface 10 of the hollow shape material 1. A bridge 45 for supporting the mandrel 41 is arranged at a position corresponding to the hollow part 15 and a space between both side surfaces 13 in the hollow shape material 1 but not arranged at a position corresponding to a space between the hollow part 15 and the lower surface 12.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an extrusion die for manufacturing a hollow section having a hollow portion, and to a hollow section and a manifold manufactured by using the extrusion die. [Background technology]

[0002] The piping manifold (manifold) to which multiple hydrogen tanks are connected is, for example, made of a long member with a rectangular cross-section whose width is longer than its length, and has a main pipe hole that is continuous in the longitudinal direction. Furthermore, multiple recesses for connecting the nozzles of the hydrogen tanks are formed on the upper surface at equal intervals along the longitudinal direction, and each recess and the main pipe hole are connected in communication with each other via a communication hole (branch pipe hole).

[0003] Conventionally, when manufacturing a manifold, a main pipe hole is drilled along the length of a long bar material with a rectangular cross section using a gun drill, and recesses and communication holes (branch pipe holes) are formed.

[0004] However, when manufacturing a manifold, if a long bar material is used, the drilling operation using a gun drill becomes difficult, which may result in a decrease in productivity.

[0005] In recent years, therefore, a method of manufacturing a long bar material (hollow material) with a hollow portion (main pipe hole) for manufacturing a manifold by extrusion molding has been investigated.

[0006] As an extrusion die for manufacturing a hollow profile, for example, a hollow die such as a porthole die is used. A porthole die includes a female die having a die hole for forming the outer peripheral surface of the hollow profile, and a male die arranged opposite the die hole and having a mandrel for forming the inner peripheral surface of the hollow section. Furthermore, the male die is formed with a plurality of portholes along the circumferential direction on the outer periphery of the mandrel, and the extrusion material passing through each porthole passes through a forming gap between the outer peripheral bearing part of the die hole and the inner peripheral bearing part of the mandrel to form the hollow profile.

[0007] In such a porthole die, a bridge that supports a mandrel is provided between adjacent portholes in the male die. In a typical porthole die, four bridges are arranged at approximately equal intervals in the circumferential direction, and the extrusion material (extrusion raw material) is once diverged at the bridge position and then merges and is integrated near the forming gap, so that linear marks called weld lines (crimping lines) are formed in the hollow profile at positions corresponding to the bridges.

[0008] For example, in the porthole die shown in Patent Document 1 below, weld lines are formed at the midpoints of the four peripheral walls (top wall, bottom wall, and both side walls) of a rectangular cylindrical hollow profile, and these four weld lines are arranged in a "cross" shape with the mandrel at the center. Also, in the porthole dies shown in Patent Documents 2 and 3 below, weld lines are formed at the four corners of each cylindrical hollow profile, and these four weld lines are arranged in an "X" shape with the mandrel at the center. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2003-71514 A [Patent Document 2] JP 2004-74204 A [Patent Document 3] Patent No. 3698927 Summary of the Invention [Problem to be solved by the invention]

[0010] Incidentally, the conventional manifold has a circular main hole formed in a long member having a rectangular cross section along the length direction, and this main hole is formed below the center position in the up-down direction (closer to the bottom). In other words, the bottom side of the surrounding wall is formed thinner and weaker than the top side and both side sides. For this reason, if a hollow extrusion material for manufacturing a manifold is molded using the porthole dies shown in Patent Documents 1 to 3, a weld line will be formed on the bottom side. In other words, a weld line that reduces strength will be formed on the thin and weak bottom side, which will cause a problem that sufficient strength may not be ensured overall.

[0011] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide an extrusion die for manufacturing hollow profiles that can form hollow profiles having sufficient strength, and further to provide a hollow profile and a manifold having sufficient strength. [Means for solving the problem]

[0012] [1] An extrusion die for manufacturing a hollow profile, the dimension between both side surfaces being longer than the dimension between the upper and lower surfaces on the outer peripheral surface, and having a hollow portion continuing in the longitudinal direction below the middle position in the vertical direction, A mandrel for forming an inner peripheral surface of a hollow section is disposed opposite to a die hole for forming an outer peripheral surface of the hollow section, An extrusion die for manufacturing hollow profiles, characterized in that a bridge for supporting the mandrel is arranged at a position corresponding to the hollow portion and both side surfaces of the hollow profile, but is not present at a position corresponding to the hollow portion and the lower surface.

[0013] [2] An extrusion die for manufacturing hollow profiles as described in the preceding paragraph 1, wherein the bridges are arranged only at positions corresponding to the middle and both side surfaces of the hollow profile.

[0014] [3] An extrusion die for manufacturing hollow profiles as described in paragraph 1 or 2 above, in which a bridge arranged at a position corresponding to the space between one of the two side surfaces and the hollow portion, and a bridge arranged at a position corresponding to the space between the other side surface and the hollow portion, are arranged in a straight line when viewed in the extrusion direction.

[0015] [4] A hollow extrusion material having a lengthwise extending hollow portion below the vertical center position, the lengthwise extending hollow portion being longer than the lengthwise extending hollow portion between the upper and lower surfaces of the outer peripheral surface. A hollow profile, characterized in that a weld line is formed at a position corresponding to a hollow portion and both side surfaces, and no weld line is present at a position corresponding to a hollow portion and a bottom surface.

[0016] [5] The hollow profile described in paragraph 4 above, wherein the hollow portion is formed by a circular hole with a diameter of 10 mm or less.

[0017] [6] A hollow profile as described in paragraph 4 or 5 above, in which the dimension from the center of the hollow portion to its bottom surface is set to 1 / 2 or less of the dimension from the center of the hollow portion to its top surface.

[0018] [7] A manifold manufactured using the hollow material according to any one of items 4 to 6 above, A manifold comprising: a hollow member having an upper surface formed with a recess; and a bottom wall formed with a communication hole communicating with the hollow member. Effect of the Invention

[0019] According to the extrusion die for manufacturing hollow profiles of the invention [1], since there is no bridge below the mandrel, it is possible to form a hollow profile without a weld line below the hollow portion. Therefore, even if the hollow portion of the hollow profile to be formed is located at the bottom, it is possible to prevent a decrease in strength due to the formation of a weld line below the hollow portion, and it is possible to form a hollow profile with sufficient strength. In addition, although weld lines are formed on both sides of the hollow profile, since the hollow profile has a wide shape with thick sides, it is possible to maintain sufficient strength as a hollow profile even considering the decrease in strength due to the formation of a weld line.

[0020] According to the extrusion die for manufacturing hollow profiles of the inventions [2] and [3], the above-mentioned effects can be obtained more reliably.

[0021] According to the hollow profile of the invention [4], sufficient strength can be ensured, similar to the hollow profile formed by the extrusion die of the invention [1] above.

[0022] According to the extrusion die for manufacturing hollow profiles of the inventions [5] and [6], the above-mentioned effects can be obtained more reliably.

[0023] According to the manifold of the invention [7], similar to the above inventions [1] and [4], sufficient strength can be ensured. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a perspective view showing a manifold according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view showing a hollow material that is a main material when manufacturing the manifold of the embodiment. [Diagram 3] FIG. 3 is an external perspective view showing a porthole die as an extrusion die for producing a hollow material in an embodiment. [Figure 4] FIG. 4 is a front view showing the porthole die of the embodiment. [Diagram 5]FIG. 5 is a vertical cross-sectional view showing a porthole die of the embodiment, which is a cross-sectional view corresponding to the cross-section taken along line VV in FIG. [Figure 6] FIG. 6 is a horizontal cross-sectional view showing the porthole die of the embodiment, which is a cross-sectional view corresponding to the cross-section taken along line VI-VI in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Fig. 1 is a perspective view showing a manifold (manifold) 2 for connecting high-pressure hydrogen tanks according to an embodiment of the present invention, and Fig. 2 is a cross-sectional view showing a hollow material 1 that is a main material for manufacturing the manifold 2. As shown in both figures, the hollow material 1 is made of an extruded material formed by extrusion. The cross section of this hollow material 1 perpendicular to the length direction (extrusion direction) is formed to be rectangular (rectangular), and the dimension (width dimension) between both side surfaces 13 at the outer circumferential surface 10 is longer than the dimension (vertical dimension) between the upper surface 11 and the lower surface 12. Furthermore, the hollow material 1 has a hollow section (main pipe hole) 15 that is circular in cross section and continues in the length direction, approximately at the middle position in the width direction and below the middle position in the vertical direction.

[0026] In the hollow extrusion 1 of this embodiment, the four peripheral surfaces constituting the outer peripheral surface 10 are referred to as the upper surface 11, the lower surface 12, and both side surfaces 13 to facilitate understanding of the invention, but these surfaces 11 to 13 are not related to the direction of gravity and may be arranged in any direction. For example, during processing or use, the upper surface 11 of the hollow extrusion 1 may be arranged to face downward or to the side with respect to the direction of gravity, the lower surface 12 may be arranged to face upward or to the side with respect to the direction of gravity, or the side surfaces 13 may be arranged to face upward or downward with respect to the direction of gravity (the same applies to the manifold 2 described below).

[0027] In this embodiment, taking into consideration the pressure of the high-pressure hydrogen flowing through the hollow material 1, it is preferable to set the diameter of the hollow portion 15 in the cross-sectional view of FIG. 1 to 10 mm or less.

[0028] In this embodiment, it is preferable that the dimension from the center of hollow portion 15 in hollow profile 1 to the bottom surface along the vertical direction be set to 1 / 2 (0.5) or less of the dimension from the center of hollow portion 15 to the top surface along the vertical direction in the cross-sectional view of Fig. 1. In other words, it is preferable that the ratio of the dimension from the center of hollow portion 15 to the bottom surface along the vertical direction to the dimension from the center of hollow portion 15 to the top surface along the vertical direction be set to 1:2 or more.

[0029] On the other hand, as shown in Figure 1, a manifold 2 manufactured using a hollow profile 1 has recesses 21 for connecting hydrogen tanks formed at predetermined intervals along the length direction on the upper surface of the hollow profile 1, and the recesses 21 are connected to the hollow section (main pipe hole) 15 by communication holes (branch pipe holes) 22 provided at the bottom of each recess 21.

[0030] As will be described in detail later, between the hollow portions 15 of the hollow profile 1 and the manifold 2 and both side surfaces 13, continuous linear (planar) weld lines (crimped lines) 16 are formed along the length direction.

[0031] FIG. 3 is an external perspective view showing a porthole die (hollow die) 3, which is an extrusion die for manufacturing hollow profiles in this embodiment, FIG. 4 is a front view of the porthole die 3 of the embodiment, FIG. 5 is a vertical cross-sectional view of the porthole die 3 of the embodiment, and FIG. 6 is a horizontal cross-sectional view of the porthole die 3 of the embodiment.

[0032] As shown in these figures, the porthole die 3 of this embodiment includes a male die 4 and a female die 5, and is formed by combining these dies 4, 5. In this embodiment, the downstream side in the extrusion direction (the right direction in Figs. 5 and 6) will be described as the "front side" or "front side", and the upstream side (the left direction in Figs. 5 and 6) will be described as the "rear side" or "back side".

[0033] The female die 5 is formed in a disk shape, and in the center is formed a rectangular die hole 51 whose diameter increases toward the front, and the inner peripheral surface of the rear end portion of this die hole 51 is configured as a bearing portion (outer peripheral bearing portion) 52. This outer peripheral bearing portion 52 is used to form the outer peripheral surface of the hollow profile 1, and is formed in a rectangular shape whose width dimension is longer than its vertical dimension in accordance with the cross-sectional outer peripheral shape of the hollow profile 1.

[0034] The male die 4 is formed in an annular shape, and has a through hole 40 penetrating in the front-rear direction at approximately the center. Furthermore, in the male die 4, a mandrel 41 extending in the front-rear direction is arranged inside the through hole 40, and a portion of the outer peripheral surface of the tip of this mandrel 41 that corresponds to the outer peripheral bearing part 52 of the female die 5 is configured as a male side bearing part 42 (inner peripheral side bearing part). The inner peripheral side bearing part 42 forms the inner peripheral surface of the hollow part 15 of the hollow extrusion material 1, and is formed in a circular cross section corresponding to the cross-sectional shape of the hollow part 15 in the hollow extrusion material 1.

[0035] The mandrel 41 is disposed below the center position of the through hole 40 of the male die 4, corresponding to the hollow portion 15 of the hollow profile 1. This mandrel 41 is supported by the inner peripheral surface of the through hole 40 of the male die 4 via bridges 45. The bridges 45 are disposed horizontally from both side ends of the mandrel 41 toward both sides, and disposed so as to bridge between both side ends of the mandrel 41 and the inner peripheral side surface of the through hole 40 in the male die 4. The bridges 45 on both sides are disposed linearly, sandwiching the mandrel 41 between them, when viewed from the front in FIG. 4 (when viewed from the extrusion direction).

[0036] In the porthole die 3 of this embodiment, portholes 46 are formed on the upper and lower sides of both bridges 45 that are arranged in a straight line. That is, the porthole die 3 of this embodiment has two bridges 45 and two portholes 46.

[0037] In the porthole die 3 of this embodiment, the bridges 45 are provided only on both sides of the mandrel 41, and are not present below the mandrel 41, nor above the mandrel 41. In other words, the bridges 45 are disposed at positions corresponding to the space between the hollow portion 15 and both side surfaces 13 in the hollow profile 1, and are not present at positions corresponding to the space between the hollow portion 15 and the upper surface 11, or between the hollow portion 15 and the lower surface 12 in the hollow profile 1.

[0038] The porthole die 3 having the above configuration is set in the container of an extruder, and extrusion processing is performed. In this extrusion processing, an extrusion material (metal material) such as an aluminum alloy in the container flows under pressure through the porthole 46 of the male die 4. At this time, the extrusion material is once divided at the position of the bridge 45, passes through the bridge 45, and then merges. Then, it passes through the forming gap between the bearing parts 42, 52 of the mandrel 41 and the die hole 51, and the outer peripheral surface 10 of the hollow profile 1 and the inner peripheral surface of the hollow part 15 are formed, thereby forming the hollow profile 1. In the hollow profile 1 produced by this extrusion processing, linear weld lines (crimped lines) 16 are formed at the positions corresponding to the bridge 45, that is, from both sides of the inner peripheral surface of the hollow part of the hollow profile 1 to both side surfaces 13.

[0039] In this embodiment, the weld line 16 of the hollow profile 1 is formed only at a position corresponding to the hollow portion 15 and both side surfaces 13, and is not formed at a position corresponding to the hollow portion 15 and the bottom surface 12, so that the strength of the hollow profile 1 can be sufficiently ensured, as described in detail below.

[0040] That is, in the hollow extrusion 1 for manufacturing the manifold 2 for connecting high-pressure hydrogen tanks as in this embodiment, the hollow portion 15 is disposed below the vertical center position, and therefore the portion below the hollow portion 15 has lower strength than the portions on both sides of the hollow portion 14 and the portion above the hollow portion 15. In this structure, if a weld line is formed below the hollow portion 15, the strength of the portion below the hollow portion 15 in the hollow extrusion 1 will be further reduced due to the reduction in strength caused by the presence of the weld line, making it difficult to ensure sufficient strength for the extrusion as a whole.

[0041] As described above, in this embodiment, since no weld line 16 is formed in the lower part of the hollow section 15 in the hollow profile 1, even if the hollow section 15 is formed on the lower side, a decrease in strength due to the weld line 16 can be prevented, and sufficient strength can be ensured for the hollow profile 1.

[0042] In this embodiment, the strength can be further improved because no weld line 16 is formed in the upper portion of the hollow section 15 in the hollow shape member 1. That is, when the manifold 2 is manufactured in the upper portion of the hollow shape member 1, recesses 21 and communication holes 22 are formed as shown in Fig. 1, which may result in a corresponding decrease in strength, but in this embodiment, the weld line 16 is not formed in the upper portion of the hollow section 15, which prevents a decrease in strength due to the presence of the weld line 16, and the strength can be further improved.

[0043] Furthermore, in this embodiment, although weld lines 16 are formed on both sides of the hollow profile 1, the hollow profile 1 formed is wide and sufficient thickness can be ensured on both sides. Therefore, even taking into account the reduction in strength due to the formation of the weld lines 16, sufficient strength can be ensured to allow the hollow profile 1 to be used as a manifold without any problems.

[0044] Furthermore, in this embodiment, the bridges 45 on both sides of the mandrel 41 are arranged in a straight line on either side of the mandrel 41, so that the mandrel 41 can be supported in a balanced manner from both sides, and the mandrel 41 can be maintained in its position with high precision even against the flow pressure of the extrusion material, making it possible to form a hollow profile 1 with high precision and high quality. [Industrial Applicability]

[0045] The extrusion die for manufacturing a hollow section according to the present invention can be used to mold a hollow section used in manufacturing a manifold for connecting a high-pressure hydrogen tank. [Explanation of symbols]

[0046] 1: Hollow profile (extrusion profile) 10: Outer surface 11:Top surface 12: Bottom surface 13: Side 15: Hollow part 16: Weld line 2: Manifold 21: Recess 22:Communication hole 3: Porthole die (extrusion die for manufacturing hollow shapes) 41: Mandrel 45: Bridge 51: Die hole

Claims

1. An extrusion die for manufacturing a hollow profile, the extrusion die being for manufacturing a hollow profile having a dimension between both side surfaces longer than a dimension between an upper surface and a lower surface on an outer peripheral surface, and having a hollow portion continuing in a longitudinal direction below a middle position in a vertical direction, A mandrel for forming an inner peripheral surface of a hollow section is disposed opposite to a die hole for forming an outer peripheral surface of the hollow section, An extrusion die for manufacturing hollow profiles, characterized in that a bridge for supporting the mandrel is arranged at a position corresponding to the hollow portion and both side surfaces of the hollow profile, but is not present at a position corresponding to the hollow portion and the lower surface.

2. 2. The extrusion die for manufacturing a hollow profile according to claim 1, wherein the bridges are arranged only at positions corresponding to a middle portion and both side surfaces of the hollow profile.

3. 3. An extrusion die for manufacturing hollow profiles as described in claim 1 or 2, wherein a bridge arranged at a position corresponding to the space between one of the two side surfaces and the hollow portion, and a bridge arranged at a position corresponding to the space between the other side surface and the hollow portion, are arranged in a straight line when viewed from the extrusion direction.

4. A hollow extrusion material having a lengthwise continuous hollow portion below the vertical center position, the lengthwise dimension of the side surface being longer than the lengthwise dimension of the upper surface and the lower surface of the outer circumferential surface, A hollow profile, characterized in that a weld line is formed at a position corresponding to a hollow portion and both side surfaces, and no weld line is present at a position corresponding to a hollow portion and a bottom surface.

5. The hollow shape member according to claim 4, wherein the hollow portion is formed by a circular hole having a diameter of 10 mm or less.

6. 6. The hollow shape member according to claim 4, wherein a dimension from the center of the hollow portion to a lower surface is set to be equal to or less than half a dimension from the center of the hollow portion to an upper surface.

7. A manifold manufactured using the hollow shape material according to claim 4 or 5, A manifold comprising: a hollow member having an upper surface formed with a recess; and a bottom wall formed with a communication hole communicating with the hollow member.

Images