JP4855705B2 - Flexible tube joint member connection method - Google Patents

Description

The present invention relates to a flexible tube used for a gas body having a low gas molecular weight (hydrogen, helium, carbon dioxide, refrigerant gas, etc.) or a high-pressure pipe, such as a refrigerant pipe of a vehicle air conditioner or a hydrogen pipe of a fuel cell vehicle. The present invention relates to a joint member connection method .

  In general, a flexible tube formed of a bellows-like metal tube has flexibility and pressure resistance, and is impermeable to various gases compared to non-metallic flexible tubes such as rubber. It is used for piping for gas bodies.

  Conventionally, this type of flexible tube includes a tube body made of a metal tube formed in an accordion shape, and a reinforcing blade that covers the outer peripheral surface of the tube body. A device with a joint for connecting to a device or the like is known. In this case, the joint is composed of a cylindrical joint member and other parts, and is generally joined by welding the joint member to the end of the tube body. In this case, a high sealing performance can be obtained by integrating the tube body and the joint member by welding, but since the welded portion of the tube body is deteriorated by welding heat, durability against external forces such as bending and changes in internal pressure is reduced. There was a possibility that the joint part was damaged earlier than the service life.

  Also, as a joining structure that does not use welding, there is known a structure in which the ends of the tube main body and the reinforcing blade are sandwiched between the joint member and the fixing ring, and these are fixed to the joint member by caulking of the fixing ring. (For example, refer to Patent Document 1). However, in this case, since the sealing performance between the joint member and the tube main body and the connection strength between the reinforcing blade and the joint member must be ensured by one fixing ring, the fixing ring is caulked. There is a need. For this reason, there is a drawback that the diameter of the fixing ring is increased, the inner peripheral surface thereof is deformed into a polygonal shape instead of a perfect circle, and a uniform tightening force cannot be obtained in the circumferential direction.

Therefore, the tube body is fixed to a predetermined position of the joint member by the first fixing ring, and the reinforcing blade is fixed to another predetermined position of the joint member by the second fixing ring, and the inner peripheral surface of the first fixing ring. There is known one in which a convex portion provided on the outer peripheral surface of the joint member and a concave portion provided on the outer peripheral surface of the joint member are fitted together by caulking of a fixing ring (for example, see Patent Document 2). In this case, since the tube body and the reinforcing blade are caulked and fixed to the joint member at different locations, the diameter of each fixing ring by caulking is reduced compared to when the tube body and the reinforcing blade are fixed by caulking of one fixing ring. Each amount can be reduced.
Japanese Utility Model Publication No. 4-82484 JP-A-7-301379

  However, in the latter connection structure, the convex portion of the first fixing ring and the concave portion of the joint member are fitted by caulking of the first fixing ring, so that the convex portion and the concave portion are fitted. Only the caulking tightening force is reduced. For this reason, the sealing performance between the tube main body and the joint member cannot be improved, and there is a problem that internal fluid is likely to leak in the gas body pipe or the high pressure pipe having a small gas molecular weight.

The present invention has been made in view of the above problems, and the object thereof is to provide a space between the tube body and the joint member even when the tube body and the reinforcing blade are fixed to the joint member at different locations. Another object of the present invention is to provide a joint member connecting method for a flexible tube that can improve the sealing performance of the flexible tube.

In order to achieve the above object, the present invention is connected to a tube main body made of a metal tube formed in a bellows shape excluding the end portion, a reinforcing blade covering the outer peripheral surface side of the tube main body, and an end portion of the tube main body. A cylindrical joint member, a first fixing ring for fixing the end of the tube body at a predetermined axial position of the joint member by reducing the diameter by caulking, and an end of the reinforcing blade by reducing the diameter by caulking in the second joint member connection method of full lexical Bull tube with a fixing ring for fixing the part to the other axial position of the joint member, the outer peripheral surface of the joint member corresponding to the fixed position of the first fixing ring circumferential protrusions provided with extending in a direction, a first locking ring, the inner circumferential surface joint member while reduced in diameter by crimping as the outer peripheral surface forms a flat surface along the axial direction after the crimping to Pressed through the end of the tube body on the convex portion, and a recess formed on the inner peripheral surface of the first fixing ring by pressure contact between the convex portion to engage with the convex portion of the coupling member.

  As a result, when the diameter of the first fixing ring is reduced by caulking, the first fixing ring comes into pressure contact with the convex portion of the joint member via the end portion of the tube body, and protrudes to the inner peripheral surface of the first fixing ring. Since the concave portion that engages with the portion is formed, the first fixing ring is fixed to the joint member in a state in which the tightening force by caulking is generated in the convex portion and the concave portion.

  According to the present invention, even when the tube main body and the reinforcing blade are fixed to the joint member at different locations, the tube main body can be fixed to the joint member in a state in which a tightening force is generated by caulking. And the joint member can be significantly improved in sealing performance.

  1 to 3 show an embodiment of the present invention. FIG. 1 is a partial sectional side view of a flexible tube, FIG. 2 is a principal side sectional view showing a part of the manufacturing process, and FIG. It is a principal part expanded side surface sectional view which shows a part of manufacturing process.

  The flexible tube includes a tube main body 1 made of a flexible metal tube, a reinforcing blade 2 that covers the outer peripheral surface of the tube main body 1, a cylindrical joint member 3 connected to an end of the tube main body 1, A first fixing ring 4 that fixes the end of the tube body 1 to a predetermined axial position of the joint member 3 and a second fixing that fixes the end of the reinforcing blade 2 to another predetermined position in the axial direction of the joint member 3. It is composed of a ring 5.

  The tube body 1 is made of, for example, a stainless steel thin tube, and is formed in a bellows shape so as to have flexibility except for an end portion. That is, the peripheral surface of the tube body 1 is bent into a waveform so that the large diameter portions 1a and the small diameter portions 1b are alternately arranged in the tube axis direction, and a straight portion 1c is formed at the end thereof. Has been.

  The reinforcing blade 2 is formed by braiding a reinforcing wire by braiding, and SUS304 stainless wire, aramid fiber, polyester fiber, or the like is used as the reinforcing wire.

  The joint member 3 is made of a highly rigid metal such as iron, for example, and another joint part (not shown) is assembled to one end side thereof. On the outer peripheral surface on the other end side of the joint member 3, convex portions 3 a extending in the circumferential direction are provided in two axial directions, and each convex portion 3 a is formed in a quadrangular cross section.

  The first fixing ring 4 is made of a softer metal than the joint member 3, that is, aluminum, copper, or superplastic stainless steel, and is formed in a cylindrical shape having a length substantially equal to the straight portion 1 c of the tube body 1. In this case, the first fixing ring 4 before being fixed to the joint member 3 is formed to have an inner diameter larger than the outer diameter of the straight portion 1c of the tube body 1, and is fixed to the other axial end side of the joint member 3. It has become so.

  The second fixing ring 5 is made of general carbon steel, stainless steel or soft metal, and is formed in a cylindrical shape having a predetermined length. The second fixing ring 5 before being fixed to the joint member 3 is formed to have an inner diameter larger than the outer diameter of the reinforcing blade 2 disposed on the outer peripheral surface side of the joint member 3, and the axial direction of the joint member 3 It is fixed to one end side.

  When manufacturing the flexible tube, as shown in FIG. 2 (a), the straight portion 1c of the tube body 1 is inserted into the first fixing ring 4, and the other end of the joint member 3 is connected to the straight portion 1c. Then, the first fixing ring 4 is reduced in diameter by caulking as shown in FIG. As a result, the first fixing ring 4 comes into pressure contact with each convex portion 3a of the joint member 3 via the straight portion 1c of the tube main body 1, and the inner periphery of the first fixing ring 4 as shown in FIG. 3 (b). Concave portions 4a that engage with the respective convex portions 3a are formed in two places on the surface. At that time, since the first fixing ring 4 is formed of a softer metal than the joint member 3, the inner peripheral surface side of the first fixing ring 4 is plastically deformed without deformation of each convex portion 3a. A recess 4a is formed. As a result, the first fixing ring 4 is fixed to the joint member 3 in a state where the tightening force by caulking is generated in each convex portion 3a and each concave portion 4a, and the corner portions 3b on both axial sides of the convex portion 3a ( The right angle portion) bites into the tube body 1 side, and the space between the tube body 1 and the joint member 3 is securely sealed. Next, as shown in FIG. 2 (b), the outer peripheral surface of the tube body 1 is covered with the reinforcing blade 2, and the end of the reinforcing blade 2 is covered with the first fixing ring 4 at one end side of the joint member 3. One end side of the joint member 3 covered with the reinforcing blade 2 is inserted into the second fixing ring 5 and the diameter of the second fixing ring 5 is reduced by caulking. As a result, the second fixing ring 5 is pressed against the joint member 3 via the reinforcing blade 2, and the reinforcing blade 2 is fixed to the joint member 3.

  Thus, according to this embodiment, since the tube main body 1 and the reinforcing blade 2 are caulked and fixed to the joint member 3, the joint portion may be deteriorated by welding heat as in the case of joining by welding. Therefore, the durability can be improved. In this case, the tube main body 1 and the reinforcing blade 2 are caulked and fixed to the joint member 3 at different locations by the first and second fixing rings 4 and 5 respectively. Compared with the case where the fixing ring is fixed by caulking, the diameter reduction amount of each of the fixing rings 4 and 5 by caulking can be reduced. Thereby, a caulking state close to a perfect circle can be obtained without deforming the inner peripheral surfaces of the fixing rings 4 and 5 into a polygonal shape, and the fixing rings 4 and 5 can be fixed with a uniform tightening force in the circumferential direction.

  Moreover, by providing the convex part 3a extended in the circumferential direction on the outer peripheral surface of the joint member 3, and press-contacting the 1st fixing ring 4 to each convex part 3a of the joint member 3 via the straight part 1c of the tube main body 1. Since the concave portions 4a formed on the inner peripheral surface of the first fixing ring 4 are engaged with the convex portions 3a of the joint member 3, the tightening force by caulking is applied to the convex portions 3a and the concave portions 4a. In the state which arose, the 1st fixing ring 4 can be fixed to the coupling member 3, and the sealing performance between the tube main body 1 and the coupling member 3 can be improved markedly.

  In this case, since the convex portion 3a of the joint member 3 is formed in a quadrangular cross section, each corner portion 3b of the convex portion 3a can be bitten into the tube body 1, and not only the tightening force by caulking but also the convex portion The sealing property can also be improved by biting each corner 3b of 3a.

  Furthermore, since the first fixing ring 4 is made of a softer metal than the joint member 3, the concave portion 4a of the first fixing ring 4 can be formed without deforming the convex portion 3a. Engagement with the recess 4a can be reliably performed.

  In this case, since the first fixing ring 4 is formed of aluminum, copper, or superplastic stainless steel, the deformation as a soft metal can be reliably performed, and the engagement between the convex portion 3a and the concave portion 4a is more reliably performed. be able to.

  Moreover, since the convex part 3a of the joint member 3 and the concave part 4a of the 1st fixing ring 4 were each provided in the axial direction multiple places, the sealing performance of the tube main body 1 and the joint member 3 can be improved more.

  In the above embodiment, the projections 3a and the recesses 4a are provided at a plurality of positions in the axial direction, respectively, but may be provided at only one position.

  FIG. 4 is a partial cross-sectional side view of a flexible tube showing another embodiment of the present invention, and the same reference numerals are given to the same components as those in the above embodiment.

  The flexible tube of the present embodiment includes a filler 6 that covers the outer peripheral surface of the tube body 1, and the outer peripheral surface of the filler 6 is covered with the reinforcing blade 2. The filler 6 is made of an elastomer such as silicone rubber, and is filled in the outer peripheral surface of the tube body 1 without a gap. Further, in the present embodiment, as in the above-described embodiment, the convex portion 3a of the joint member 3 and the concave portion 4a of the first fixing ring 4 are provided at two positions with an interval in the axial direction.

  According to this embodiment, since the elastomeric filler 6 is interposed between the tube main body 1 and the reinforcing blade 2, the vibration of the tube main body 1 can be absorbed by the filler 6, and the tube main body. Friction due to contact between 1 and the reinforcing blade 2 can be prevented.

  In each of the above embodiments, the convex portion 3a of the joint member 3 is formed in a quadrangular cross section. However, the convex portion 3c shown in FIG. 5 is formed in a trapezoidal cross section, or FIG. You may make it form in a cross-sectional substantially semicircle shape like the convex part 3d shown.

The partial cross section side view of the flexible tube which shows one Embodiment of this invention Side sectional view of the main part showing a part of the flexible tube manufacturing process Main part enlarged side sectional view showing a part of the manufacturing process of the flexible tube The partial cross section side view of the flexible tube which shows other embodiment of this invention Side sectional view of the main part of the joint member showing a modification of the convex part Side sectional view of the main part of the joint member showing another modification of the convex portion

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Tube main body, 2 ... Reinforcing blade, 3 ... Joint member, 3a, 3c, 3d ... Convex part, 4 ... 1st fixing ring, 4a ... Concave part, 5 ... 2nd fixing ring.

Claims (7)

A tube body made of a metal tube formed in a bellows shape excluding the end portion, a reinforcing blade covering the outer peripheral surface side of the tube body, a cylindrical joint member connected to the end portion of the tube body, and caulking A first fixing ring that fixes the end of the tube body to a predetermined position in the axial direction of the joint member by reducing the diameter , and another end position of the joint member in the other axial direction of the joint member by reducing the diameter by caulking in the joint member connection method of full lexical Bull tube and a second fixing ring for fixing to,
Providing a protrusion extending in the circumferential direction on the outer peripheral surface of the joint member corresponding to the fixing position of the first fixing ring,
The first fixing ring is pressed against the convex portion of the joint member via the end of the tube body while the diameter of the first fixing ring is reduced by caulking so that the outer peripheral surface after crimping forms a flat surface along the axial direction. And a joint member connecting method for a flexible tube, wherein a concave portion formed on the inner peripheral surface of the first fixing ring is engaged with the convex portion of the joint member by pressure contact with the convex portion . The method for connecting a joint member of a flexible tube according to claim 1, wherein the convex portion of the joint member is formed in a quadrangular cross section. The method for connecting a flexible tube joint member according to claim 1, wherein the convex portion of the joint member is formed in a trapezoidal cross section. The method for connecting a flexible tube joint member according to claim 1, wherein the convex portion of the joint member is formed in a substantially semicircular cross section. The said 1st fixing ring is formed with a softer metal than a joint member. The joint member connection method of the flexible tube as described in any one of Claim 1 thru | or 4 characterized by the above-mentioned. Wherein the first fixing ring, aluminum, copper, joint member connection method according to claim 5, wherein the flexible tube, characterized by formed by any one of the superplastic stainless steel. Fitting flexible tube according to any one of claims 1 to 6, characterized in that Ru is provided in the axial direction a plurality of locations of the joint member of the convex portion and the first recess of one place or the joint member of the fixed ring Member connection method .

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