Resin tube connection device

Abstract

To provide a resin tube connection device which can prevent breakage of a resin tube.SOLUTION: A resin tube connection device includes a resin tube, a resin extension part, and a metal sleeve. The resin extension part has a seal surface contactable with a contact surface. The resin extension part has a second flow channel which communicates with a first flow channel of the resin tube and is opened in the seal surface. The seal surface projects from the end face of the metal sleeve in an axial direction. A maximum length of a contact region of the resin extension part and the metal sleeve in an axial direction in an outside surface is larger than thickness of the resin layer in a radial direction.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a resin tube connecting device. [Background technology]

[0002] For example, in liquid chromatography, when analyzing a sample that is easily adsorbed to metal or when using a mobile phase that is corrosive to metal, a resin tube may be used. The resin tube has a structure in which the inner surface of a metal tube is coated with a resin layer. When connecting a resin tube to, for example, a separation column, it is necessary to ensure the airtightness of the resin tube and the flow path of the separation column. For this purpose, a structure for sealing the end face of the resin tube has been proposed. For example, Patent Document 1 describes a plug unit for connecting plug capillaries for high-performance liquid chromatography.

[0003] The plug unit comprises a plug capillary, a pressing body and a sealing member. The plug capillary has an outer covering made of a hard material and an inner covering made of an elastic material. The inner covering has an end region extending radially outward. The pressing body and the sealing member are provided to cover the outer circumferential surface of the plug capillary. A bushing unit is arranged in the separation column. The bushing unit is provided with a receiving recess. The plug unit is screwed into the receiving recess of the bushing unit. [Patent Document 1] JP 2014-98694 A Summary of the Invention [Problem to be solved by the invention]

[0004] According to the plug unit of Patent Document 1, the contact surface of the pressing body is pressed against the receiving recess of the bush unit and the end region is plastically deformed, thereby sealing the flow path in the plug capillary.

[0005] However, when replacing a component such as a separation column, it is necessary to remove the plug capillary from the component by removing the plug unit from the bush unit, and then attach the plug capillary to the replaced component by screwing the plug unit into the bush unit. Repeated removal and attachment of the plug capillary can damage the end of the plug capillary.

[0006] An object of the present invention is to provide a resin tube connecting device capable of preventing damage to the resin tube. [Means for solving the problem]

[0007] A resin tube connection device according to one aspect of the present invention is a resin tube connection device connectable to a connected member having a contact surface with a flow path hole, the resin tube having a metal tube and a resin layer formed on the inner surface of the metal tube and having a first flow path surrounded by the resin layer, a resin extension portion formed integrally with the resin tube from the same material as the resin tube and protruding in the axial direction from the end of the resin layer and provided so as to protrude outward beyond the metal tube in the radial direction of the resin tube, and a metal sleeve formed to cover the outer surface of the metal tube and the outer surface of the resin extension portion, the resin extension portion having a sealing surface capable of coming into contact with the contact surface, and a second flow path communicating with the first flow path of the resin tube and opening at the sealing surface, the sealing surface protruding in the axial direction beyond the end face of the metal sleeve, and the maximum length of the contact area of ​​the outer surface between the resin extension portion and the metal sleeve in the axial direction is greater than the thickness of the resin layer in the radial direction.

[0008] A resin tube connection device according to another aspect of the present invention is a resin tube connection device connectable to a connected member having a contact surface with a flow path hole, the device comprising: a resin tube having a metal tube, and a resin layer formed on the inner surface of the metal tube and protruding in the axial direction from an end face of the metal tube, the resin tube having a flow path surrounded by the resin layer; a resin sealing material joined to the resin layer so as to cover the outer surface of the part of the resin layer protruding from the metal tube; and a metal sleeve formed to cover the outer surface of the metal tube and an outer surface of the resin sealing material, the resin sealing material having a sealing surface capable of coming into contact with the contact surface and having an opening communicating with the flow path of the resin tube, the sealing surface protruding in the axial direction beyond the end face of the metal sleeve, and the maximum length of the contact area of ​​the outer surface between the resin sealing material and the metal sleeve in the axial direction is greater than the thickness of the resin layer in the radial direction. Effect of the Invention

[0009] According to the present invention, it is possible to provide a resin tube connecting device capable of preventing damage to the resin tube. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an example of a resin tube connecting structure using a resin tube connecting device according to the first embodiment. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing the configuration of the resin tube connecting device according to the first embodiment. [Diagram 3] FIG. 3 is a schematic cross-sectional view showing the configuration of a resin tube connecting device according to the second embodiment. [Figure 4] 4 is a cross-sectional view of the resin tube connecting device of FIG. 3 taken along line AA. [Diagram 5] FIG. 5 is a cross-sectional view showing another example of the configuration of the recess of the metal sleeve and the fitting portion of the resin expansion portion. [Figure 6] FIG. 6 is a cross-sectional view showing still another example of the configuration of the recess of the metal sleeve and the fitting portion of the resin expansion portion. [Figure 7]FIG. 7 is a schematic cross-sectional view showing the configuration of a resin tube connecting device according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A resin tube connecting device according to an embodiment of the present invention will be described in detail below with reference to the drawings.

[0012] (1) First embodiment Fig. 1 is a schematic cross-sectional view showing an example of a resin tube connection structure using a resin tube connection device according to the first embodiment. As shown in Fig. 1, a resin tube connection structure 100 includes a resin tube connection device 1, a bushing 200, and a male nut 300. The bushing 200 is an example of a connected member.

[0013] The resin tube connection device 1 includes a resin tube 10, a resin expansion portion 20, and a metal sleeve 30. The resin tube 10 is composed of a metal tube 11 and a resin layer 12. The resin tube 10 is provided with a first flow path p1 surrounded by the resin layer 12. Hereinafter, one direction in the axial direction of the resin tube 10 will be referred to as the forward direction, and the opposite direction to the one direction will be referred to as the rearward direction.

[0014] The resin extension portion 20 is formed integrally with the resin tube 10. The resin extension portion 20 is provided with a second flow path p2 that communicates with the first flow path p1. The resin extension portion 20 has a sealing surface 21 perpendicular to the axial direction. The second flow path p2 has an opening 24 on the sealing surface 21. The metal sleeve 30 is formed to cover the metal tube 11 and the resin extension portion 20.

[0015] The bushing 200 is formed with an accommodating recess 210 and a flow passage hole 220. The accommodating recess 210 includes a large diameter portion 211, a tapered portion 212, and a small diameter portion 213 in this order. A female thread portion 215 is formed on the inner peripheral surface of the large diameter portion 211. The tapered portion 212 has an inner diameter that gradually decreases from the front end of the large diameter portion 211 toward the front. The small diameter portion 213 extends toward the front from the front end of the tapered portion 212. A contact surface 214 is formed on the front end of the small diameter portion 213. The bushing 200 is formed with a flow passage hole 220 that penetrates the bushing 200 toward the front from the contact surface 214. In this embodiment, the cross-sectional area of ​​the flow passage hole 220 is smaller than the area (opening area) of the opening 24 of the resin expansion portion 20 on the seal surface 21.

[0016] The male nut 300 has a fastening portion 301 and a protruding portion 302. The male nut 300 has an attachment hole 303 and a through hole 304. The fastening portion 301 is a portion to which force is applied when fastening the male nut 300. The fastening portion 301 is formed so as to be held by a fastening tool such as a wrench, and has, for example, a polygonal cross-sectional shape. The outer peripheral surface of the protruding portion 302 is formed with a male thread portion 315 that corresponds to the female thread portion 215 of the large diameter portion 211 of the bushing 200. The attachment hole 303 extends rearward from the front end of the protruding portion 302. A bottom surface 305 is formed at the rear end of the attachment hole 303. The through hole 304 penetrates the male nut 300 rearward from the bottom surface 305.

[0017] The resin tube connection device 1 is accommodated in the attachment hole 303 of the male nut 300. The resin tube 10 is inserted into the through hole 304 of the male nut 300. In this state, the protruding portion 302 of the male nut 300 is fitted into the accommodating recess 210 of the bushing 200, and torque is applied to the fastening portion 301 of the male nut 300 by a fastening tool. As a result, the male nut 300 is screwed forward in a state in which the female thread portion 215 of the bushing 200 and the male thread portion 315 of the male nut 300 are screwed together.

[0018] At this time, the rear end surface of the resin tube connection device 1 contacts the bottom surface 305 of the male nut 300. This causes the resin tube connection device 1 to move forward, and the seal surface 21 of the resin expansion part 20 is pressed against the contact surface 214 of the bushing 200. In this state, the resin expansion part 20 is plastically deformed, thereby sealing between the flow path hole 220 and the second flow path p2. As a result, the fluid that has flowed into the flow path hole 220 of the bushing 200 is prevented from leaking out into the accommodating recess 210.

[0019] FIG. 2 is a schematic cross-sectional view showing the configuration of the resin tube connecting device according to the first embodiment. The metal tube 11 is made of, for example, stainless steel. The metal tube 11 may be made of other metals such as titanium, iron, copper, or alloys. An end face 11a perpendicular to the axial direction is formed at the front end of the metal tube 11. The resin layer 12 has a thickness t1 in the radial direction. The resin layer 12 is made of, for example, PEEK (polyether ether ketone). The resin layer 12 may be made of other resins such as fluororesin. In addition, the resin tube 10 has a first flow path p1 surrounded by the resin layer 12. In this embodiment, the metal tube 11, the resin layer 12, and the first flow path p1 each have a circular cross section.

[0020] The resin extension portion 20 protrudes forward from the front end of the resin layer 12 and protrudes outward beyond the metal tube 11 in the radial direction of the resin tube 10. The resin extension portion 20 has a thickness t2 in the radial direction that is greater than a thickness t1 of the resin layer 12. The resin extension portion 20 is made of the same material as the resin layer 12 and is formed by integral molding with the resin layer 12. For example, the resin layer 12 and the resin extension portion 20 may be formed by thermoforming, or may be formed by thermoforming and compression molding at room temperature.

[0021] In this embodiment, the resin extension portion 20 is formed in a cylindrical shape having a front end surface, a rear end surface 22, and an outer circumferential surface. The shape of the resin extension portion 20 is not limited to a cylindrical shape, and may be another shape such as a prismatic shape or a D-cut shape. The front end surface of the resin extension portion 20 is the seal surface 21, and the outer circumferential surface is the outer surface 23. In this embodiment, the second flow path p2 and the opening 24 each have a circular cross section. In this embodiment, the second flow path p2 has an inner diameter equal to that of the first flow path p1. In this embodiment, the cross-sectional area of ​​the opening 24 gradually increases from the cross-sectional area of ​​the second flow path p2. The inner diameter of the opening 24 in the seal surface 21 is larger than the inner diameter of the first flow path p1. As a result, the opening area of ​​the opening 24 is larger than the cross-sectional area of ​​the first flow path p1. The outer surface 23 extends in the axial direction from the outer edge of the seal surface 21 to the outer edge of the rear end surface 22 in the axial direction. The rear end surface 22 is located at the end surface 11 a of the metal tube 11 .

[0022] The metal sleeve 30 is formed so as to cover the outer peripheral surface of the metal tube 11 and the outer surface 23 of the resin extension portion 20. The metal sleeve 30 is formed of, for example, stainless steel. The metal sleeve 30 may be formed of other metals such as titanium, iron, copper, or alloys. An end surface 30a is formed at the front end of the metal sleeve 30.

[0023] The sealing surface 21 of the resin expansion portion 20 protrudes forward in the axial direction beyond the end face 30a of the metal sleeve 30. As a result, the end face 30a of the metal sleeve 30 is located between the sealing surface 21 of the resin expansion portion 20 and the end face 11a of the metal tube 11 in the axial direction.

[0024] The region where the outer surface 23 of the resin extension portion 20 and the metal sleeve 30 contact each other is called the contact region 23c. The maximum length L1 of the contact region 23c in the axial direction is greater than the thickness t1 of the resin layer 12. In this embodiment, the resin extension portion 20 is formed in a cylindrical shape, and therefore the maximum length L1 of the contact region 23c corresponds to the distance between the end face 11a of the metal tube 11 and the end face 30a of the metal sleeve 30.

[0025] In the resin tube connection device 1 according to the first embodiment, the maximum length L1 of the contact area 23c between the outer surface 23 of the resin extension portion 20 and the metal sleeve 30 is larger than the thickness t1 of the resin layer 12. In this case, since the axial length of the resin extension portion 20 is large, even if a twisting torque is applied to the resin extension portion 20, the resin extension portion 20 is unlikely to be damaged. In addition, since a large frictional force acts between the contact area 23c of the outer surface 23 of the resin extension portion 20 and the metal sleeve 30, the resin extension portion 20 is firmly fixed to the metal sleeve 30. This suppresses twisting of the resin tube 10. In addition, since the outer surface 23 of the resin extension portion 20 is held by the metal sleeve 30, even if an axial compressive force is applied to the resin extension portion 20, the seal surface 21 is prevented from expanding outward in the radial direction. Furthermore, since the resin extension portion 20 is formed in a columnar shape such as a cylindrical shape, the durability of the resin extension portion 20 is improved. As a result, when the resin tube connection device 1 is attached to the bushing 200, damage to the resin tube 10 and the resin extension portion 20 is prevented.

[0026] In addition, the opening area of ​​the opening 24 of the resin extension part 20 is larger than the cross-sectional area of ​​the flow path hole 220 of the bushing 200. Therefore, when the seal surface 21 of the resin extension part 20 is pressed against the contact surface 214, the peripheral part of the opening 24 of the resin extension part 20 does not enter the flow path hole 220. This prevents the peripheral part of the opening 24 of the resin extension part 20 from plastically deforming inward, and prevents the opening 24 of the resin extension part 20 from being blocked. In addition, since the resin of the seal surface 21 of the resin extension part 20 does not enter the flow path hole 220 of the bushing 200, the seal surface 21 of the resin extension part 20 is not pulled when the resin tube connection device 1 is removed. This prevents the seal surface 21 of the resin extension part 20 from being damaged.

[0027] In this embodiment, the outer surface 23 of the resin extension portion 20 is formed to extend in the axial direction, but the rear end surface 22 may not be formed and the outer surface 23 may be formed to extend in a curved shape from the outer edge of the sealing surface 21 to the end surface 11a of the metal pipe 11. In this embodiment, the metal pipe 11, the resin layer 12, and the first flow path p1 each have a circular cross section, but the metal pipe 11, the resin layer 12, and the first flow path p1 may have a cross section of another shape, such as a polygonal or elliptical shape.

[0028] In this embodiment, the second flow path p2 and the opening 24 each have a circular cross section, but the second flow path p2 and the opening 24 may have a cross section of another shape, such as a polygonal or elliptical shape. Furthermore, in this embodiment, the second flow path p2 has an inner diameter equal to that of the first flow path p1, but the second flow path p2 may have an inner diameter larger or smaller than that of the first flow path p1.

[0029] (2) Second embodiment Fig. 3 is a schematic cross-sectional view showing a resin tube connecting device according to a second embodiment. Fig. 4 is a cross-sectional view taken along line AA of the resin tube connecting device of Fig. 3. The resin tube connecting device 1 of Fig. 3 differs from the resin tube connecting device 1 of Fig. 2 in the following points.

[0030] An end face 30a of the metal sleeve 30 is formed flush with an end face 11a of the metal tube 11. One or more recesses 32 are provided in the end face 30a of the metal sleeve 30. In this embodiment, as shown in Fig. 4, the recesses 32 have an annular shape surrounding the resin tube 10.

[0031] 3, the resin extension portion 20 includes an end face covering portion 20a and a fitting portion 20b. The end face covering portion 20a extends from the resin layer 12 so as to protrude outward beyond the metal tube 11 in the radial direction, and is formed on the end face 11a of the metal tube 11 and the end face 30a of the metal sleeve 30. As a result, the end face covering portion 20a has a thickness t2 in the radial direction that is greater than the thickness t1 of the resin layer 12. The end face covering portion 20a has a sealing surface 21.

[0032] The fitting portion 20b is formed so as to extend rearward from the outer periphery of the end face covering portion 20a. The fitting portion 20b is formed integrally with the end face covering portion 20a. In this embodiment, as shown in FIG. 4, the fitting portion 20b has a circular cross section corresponding to the recess 32. As a result, the fitting portion 20b has a cylindrical shape. As shown in FIG. 3, the outer surface 23 of the end face covering portion 20a extends in the axial direction from the outer edge of the seal surface 21 to the rear end surface 22b of the fitting portion 20b. The fitting portion 20b is fitted into the recess 32. Since the fitting portion 20b is fitted into the recess 32, the maximum length L1 of the contact region 23c of the outer surface 23 of the resin extension portion 20 corresponds to the distance from the end surface 30a of the metal sleeve 30 to the bottom surface of the recess 32 in the axial direction (the depth of the recess 32). The resin extension portion 20 in this embodiment is formed, for example, by ultrasonic processing.

[0033] In the resin tube connection device 1 according to the second embodiment, the maximum length L1 of the contact area 23c of the resin extension portion 20 is longer than the thickness t1 of the resin layer 12. In this case, since the axial length of the resin extension portion 20 is large, even if a twisting torque is applied to the resin extension portion 20, the resin extension portion 20 is unlikely to be damaged. In addition, since the fitting portion 20b of the resin extension portion 20 is fitted into the recess 32 of the metal sleeve 30, the outer surface 23 of the resin extension portion 20 is held by the metal sleeve 30. In this case, a large frictional force acts between the contact area 23c of the outer surface 23 of the fitting portion 20b and the metal sleeve 30, so that the resin extension portion 20 is firmly fixed to the metal sleeve 30. This suppresses twisting of the resin tube 10. In addition, since the outer surface 23 of the resin extension portion 20 is held by the metal sleeve 30, even if an axial compressive force is applied to the resin extension portion 20, the seal surface 21 is prevented from expanding outward in the radial direction. As a result, damage to the resin tube 10 and the resin extension portion 20 is prevented.

[0034] Furthermore, the opening area of ​​the opening 24 of the resin extension part 20 is larger than the cross-sectional area of ​​the flow path hole 220 of the bushing 200. As a result, similar to the first embodiment, the opening 24 of the resin extension part 20 is prevented from being blocked, and the seal surface 21 of the resin extension part 20 is prevented from being damaged when the resin tube connection device 1 is removed.

[0035] The configuration of the recess 32 of the metal sleeve 30 and the fitting portion 20b of the resin expansion portion 20 is not limited to the configuration in Fig. 4. Fig. 5 is a cross-sectional view showing another example of the configuration of the recess 32 of the metal sleeve 30 and the fitting portion 20b of the resin expansion portion 20. Fig. 6 is a cross-sectional view showing yet another example of the configuration of the recess 32 of the metal sleeve 30 and the fitting portion 20b of the resin expansion portion 20.

[0036] In the example of FIG. 5, a plurality of recesses 32 are formed on the end surface 30a of the metal sleeve 30. The resin expansion portion 20 has a plurality of fitting portions 20b that can be fitted into the plurality of recesses 32. The plurality of recesses 32 and the plurality of fitting portions 20b may be provided at a plurality of positions symmetrical about the axis of the resin tube 10, or may be provided at a plurality of positions that are not symmetrical. In addition, the plurality of recesses 32 and the plurality of fitting portions 20b may be provided at equal intervals or at different intervals. The cross-sectional shape of each recess 32 may be a circle, a polygon, an ellipse, or other shape.

[0037] 6, one recess 32 is formed in the end face 30a of the metal sleeve 30. The resin extension portion 20 has one fitting portion 20b that can be fitted into the recess 32. The cross-sectional shape of the recess 32 may be circular, polygonal, elliptical, or any other shape.

[0038] 5 and 6, the same effects as those of the example of FIG. 4 can be obtained, and rotation of the resin extension portion 20 relative to the metal sleeve 30 can be reliably prevented.

[0039] (3) Third embodiment Fig. 7 is a schematic cross-sectional view showing a resin tube connecting device according to a third embodiment. The resin tube connecting device 1 in Fig. 7 differs from the resin tube connecting device 1 in Fig. 2 in the following points.

[0040] The resin tube connection device 1 includes a resin seal material 40 instead of the resin expansion portion 20. The resin seal material 40 is, for example, a packing. The resin seal material 40 is formed, for example, from PEEK (polyether ether ketone) as a separate body from the resin layer 12. The resin seal material 40 may be formed from other resins such as fluororesin. In this embodiment, the resin seal material 40 is formed in a cylindrical shape having a front end face, a rear end face, an outer peripheral surface, and an inner peripheral surface. As a result, a through hole h1 extending in the axial direction is formed in the resin seal material 40. The shape of the resin seal material 40 is not limited to a cylindrical shape, and may be another shape such as a square tube shape.

[0041] The front end surface of the resin seal material 40 is the seal surface 41, and the outer peripheral surface is the outer surface 43. The outer surface 43 is formed so as to extend in the axial direction from the outer edge of the seal surface 41 to the outer edge of the rear end surface. The inner peripheral surface 44 is formed so as to extend in the axial direction from the inner edge of the seal surface 41 to the inner edge of the rear end surface. In this case, the resin seal material 40 has a length L2 in the axial direction.

[0042] The resin layer 12 formed on the inner peripheral surface of the metal pipe 11 has a portion that protrudes forward from the end face 11a of the metal pipe 11. Hereinafter, the portion of the resin layer 12 that protrudes from the end face 11a of the metal pipe 11 is referred to as a resin layer protrusion 13. The resin layer protrusion 13 has a length L3 that is smaller than the length L2 of the resin seal material 40. The resin layer protrusion 13 is inserted into the through hole h1 of the resin seal material 40. As a result, the rear end face of the resin seal material 40 and the end face 11a of the metal pipe 11 come into contact with each other.

[0043] At this time, since the length L2 of the resin seal material 40 is greater than the length L3 of the resin layer protruding portion 13 of the resin tube 10, the seal surface 41 of the resin seal material 40 protrudes forward in the axial direction beyond the end face of the resin layer protruding portion 13. As a result, an opening 45 communicating with the first flow path p1 of the resin tube 10 is formed in the seal surface 41. The opening area of ​​the opening 45 corresponds to the cross-sectional area of ​​the through hole h1. In this embodiment, the opening area of ​​the opening 45 is greater than the cross-sectional area of ​​the flow path hole 220 of the bushing 200 in FIG. 1.

[0044] The outer peripheral surface of the resin layer protrusion 13 and the inner peripheral surface of the resin sealant 40 are joined by thermal welding. The outer peripheral surface of the resin layer protrusion 13 and the inner peripheral surface of the resin sealant 40 may also be joined by an adhesive or the like.

[0045] The metal sleeve 30 is formed to cover the outer peripheral surface of the metal pipe 11 and the outer side surface 43 of the resin seal material 40. An end face 30a is formed at the front end of the metal sleeve 30. A seal surface 41 of the resin seal material 40 protrudes forward from the end face 30a of the metal sleeve 30 in the axial direction. A region where the outer side surface 43 of the resin seal material 40 and the metal sleeve 30 contact each other is called a contact region 43c. A maximum length L1 of the contact region 43c in the axial direction is greater than a thickness t1 of the resin layer 12.

[0046] In the resin tube connection device 1 according to the third embodiment, the resin layer 12 of the resin tube 10 and the resin seal material 40 are made of a resin material. As a result, the resin layer 12 of the resin tube 10 and the resin seal material 40 are firmly fixed by thermal welding. In addition, the maximum length L1 of the contact area 43c is greater than the thickness t1 of the resin layer 12. In this case, since the axial length of the resin seal material 40 is large, the resin seal material 40 is less likely to be damaged even if a torsional torque is applied to the resin seal material 40.

[0047] In addition, a large frictional force acts between the contact area 43c of the outer surface 43 of the resin seal material 40 and the metal sleeve 30, so that the resin seal material 40 is firmly fixed to the metal sleeve 30. This suppresses twisting of the resin tube 10. In addition, since the outer surface 43 of the resin seal material 40 is held by the metal sleeve 30, even if an axial compressive force is applied to the resin seal material 40, the seal surface 41 is prevented from expanding outward in the radial direction. Furthermore, since the resin seal material 40 is formed in a cylindrical shape, the durability of the resin seal material 40 is improved. As a result, damage to the resin tube 10 is prevented.

[0048] In addition, the opening area of ​​the opening 45 of the resin seal material 40 is larger than the cross-sectional area of ​​the flow path hole 220 of the bushing 200. As a result, similar to the first embodiment, the opening 45 of the resin seal material 40 is prevented from being blocked, and the seal surface 41 of the resin seal material 40 is prevented from being damaged when the resin tube connection device 1 is removed.

[0049] Furthermore, the resin layer protruding portion 13 of the resin layer 12 of the resin tube 10 is inserted into the through hole h1 of the resin sealing material 40, and the inner peripheral surface 44 of the resin sealing material 40 is joined by thermal welding to the outer peripheral surface of the resin layer protruding portion 13. In this case, the resin tube connecting device 1 can be easily manufactured.

[0050] (4) Description It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0051] (Item 1) A resin tube connection device according to one aspect of the present invention comprises: A resin tube connecting device connectable to a connected member having a contact surface with a flow path hole, a resin tube having a metal pipe, a resin layer formed on an inner peripheral surface of the metal pipe, and a first flow path surrounded by the resin layer; a resin extension portion that is formed integrally with the resin tube from the same material as the resin tube, and that protrudes from an end of the resin layer in an axial direction and protrudes outward beyond the metal tube in a radial direction of the resin tube; a metal sleeve formed to cover an outer circumferential surface of the metal tube and an outer surface of the resin extension portion, the resin extension portion has a seal surface capable of contacting the contact surface, and a second flow path communicating with the first flow path of the resin tube and opening at the seal surface; the seal surface protrudes beyond an end surface of the metal sleeve in the axial direction, A maximum length of a contact area between the resin extension portion and the metal sleeve in the axial direction on the outer surface may be greater than a thickness of the resin layer in the radial direction.

[0052] According to the resin tube connection device described in paragraph 1, the resin extension part formed integrally with the resin layer of the resin tube is provided so as to protrude outward beyond the metal tube. In addition, the outer peripheral surface of the metal tube and the outer surface of the resin extension part are covered with a metal sleeve. When connecting the resin tube to the connected member, a torque is applied to the metal sleeve and the seal surface of the resin extension part is pressed against the contact surface of the connected member. This seals the gap between the contact surface of the connected member and the seal surface of the resin extension part with the opening of the second flow path of the resin extension part communicating with the flow path hole of the connected member.

[0053] According to the above configuration, the maximum length of the contact area between the resin extension portion and the metal sleeve in the axial direction is greater than the thickness of the resin layer in the radial direction. In this case, since the axial length of the resin extension portion is large, the resin extension portion is less likely to be damaged even if a torsional torque is applied to the resin extension portion. Furthermore, since a large frictional force acts between the resin extension portion and the metal sleeve when torque is applied to the metal sleeve, the resin extension portion is firmly held against the metal sleeve. This suppresses twisting of the resin tube. Furthermore, since the outer surface of the resin extension portion is held by the metal sleeve, the sealing surface is prevented from expanding outward in the radial direction even if an axial compressive force is applied to the resin extension portion. As a result, damage to the resin tube is prevented.

[0054] (2) In the resin tube connection device described in (1), the end face of the metal sleeve is located between the seal surface and the end face of the metal tube in the axial direction, and the outer surface of the resin extension portion extends to the end face of the metal tube in the axial direction, The maximum length of the contact area of ​​the outer surface between the resin extension portion and the metal sleeve may correspond to the distance between the end face of the metal sleeve and the end face of the metal tube in the axial direction.

[0055] According to the resin tube connection device described in item 2, the length of the resin extension portion protruding from the end face of the metal tube in the axial direction can be increased, thereby improving the durability of the resin extension portion.

[0056] (Item 3) In the resin tube connecting device according to item 2, The resin extension portion is formed in a columnar shape having one end surface, another end surface, and the outer surface, The one end surface of the columnar shape may be the sealing surface, and the other end surface of the columnar shape may be in contact with the end surface of the metal pipe in the axial direction.

[0057] According to the resin tube connecting device described in the third aspect, the resin extension portion has a columnar shape, so that the durability of the resin extension portion can be further improved.

[0058] (4) In the resin tube connecting device according to the first aspect, an end surface of the metal sleeve is formed flush with an end surface of the metal pipe; The end surface of the metal sleeve has a recess. The resin extension portion is an end surface covering portion formed on the end surface of the metal pipe and on the end surface of the metal sleeve so as to protrude outward from the metal pipe in the radial direction; The end surface covering portion may include a fitting portion that is formed integrally with the end surface covering portion, has the outer surface, and is fitted into the recess.

[0059] According to the resin tube connection device described in the fourth aspect, the fitting portion of the resin expansion portion is fitted into the recess of the metal sleeve, so that the resin expansion portion is securely held by the metal sleeve. This suppresses twisting of the resin tube when torque is applied to the metal sleeve. As a result, damage to the resin tube is prevented.

[0060] (Item 5) In the resin tube connection device according to any one of items 1 to 4, An area of ​​an opening of the second flow passage on the sealing surface of the resin extension portion may be larger than a cross-sectional area of ​​the first flow passage of the resin tube.

[0061] According to the resin tube connection device described in the fifth aspect, when the sealing surface of the resin extension portion is pressed against the contact surface of the connected member, the second flow path of the resin extension portion is prevented from being blocked.

[0062] (Item 6) A resin tube connection device according to another aspect is a resin tube connection device connectable to a connection target member having a contact surface with a flow path hole, a resin tube having a metal pipe, a resin layer formed on an inner peripheral surface of the metal pipe, protruding from an end face of the metal pipe in an axial direction, and a flow path surrounded by the resin layer; a resin seal material joined to the resin layer so as to cover an outer peripheral surface of a portion of the resin layer protruding from the metal pipe; a metal sleeve formed to cover an outer peripheral surface of the metal pipe and an outer surface of the resin seal material, the resin sealant has a sealing surface capable of coming into contact with the contact surface, and has an opening communicating with the flow path of the resin tube; the seal surface protrudes beyond an end surface of the metal sleeve in the axial direction, A maximum length of a contact area between the resin sealant and the metal sleeve in the axial direction on the outer surface may be greater than a thickness of the resin layer in the radial direction.

[0063] According to the resin tube connection device described in paragraph 6, a resin sealant is bonded to the outer peripheral surface of the resin layer of the resin tube protruding from the metal pipe. The outer peripheral surface of the metal pipe and the outer surface of the resin sealant are covered with a metal sleeve. When connecting the resin tube to the connected member, a torque is applied to the metal sleeve and the seal surface of the resin sealant is pressed against the contact surface of the connected member. This seals the gap between the contact surface of the connected member and the seal surface of the resin sealant with the opening of the resin sealant communicating with the flow path hole of the connected member.

[0064] According to the above configuration, since the resin layer of the resin tube and the resin seal material are made of resin, the resin seal material can be firmly bonded to the resin layer of the resin tube. In addition, the maximum length of the contact area between the resin seal material and the metal sleeve in the axial direction is greater than the thickness of the resin layer in the radial direction. In this case, since the axial length of the resin seal material is large, the resin seal material is less likely to be damaged even if a twisting torque is applied to the resin seal material. In addition, since a large frictional force acts between the resin seal material and the metal sleeve when a torque is applied to the metal sleeve, the outer surface of the resin seal material is firmly held by the metal sleeve. This suppresses twisting of the resin tube. In addition, since the outer surface of the resin expansion portion is held by the metal sleeve, even if an axial compressive force is applied to the resin expansion portion, the seal surface is prevented from expanding outward in the radial direction. As a result, damage to the resin tube is prevented.

[0065] (7) In the resin tube connecting device according to the 6th aspect, The resin sealant may be joined to the outer peripheral surface of the resin layer by welding.

[0066] According to the resin tube connecting device described in the seventh aspect, the resin sealant is more firmly joined to the outer circumferential surface of the resin layer.

[0067] (Item 8) In the resin tube connecting device according to item 6 or 7, An area of ​​the opening in the sealing surface of the resin sealant may be larger than a cross-sectional area of ​​the flow path of the resin tube.

[0068] According to the resin tube connecting device described in item 8, when the sealing surface of the resin extension portion is pressed against the contact surface of the connected member, the opening of the resin seal material is prevented from being blocked.

[0069] (Item 9) In the resin tube connection device according to any one of items 6 to 8, The resin sealant has a through hole extending in the axial direction, a portion of the resin layer protruding in the axial direction is inserted into the through hole of the resin seal material, and an inner peripheral surface of the resin seal material is joined to an outer peripheral surface of the resin layer, The opening may be formed in the sealing surface by causing the sealing surface of the resin sealant to protrude in the axial direction beyond an end face of the resin layer.

[0070] According to the resin tube connecting device described in paragraph 9, the resin tube connecting device can be easily manufactured by inserting the protruding portion of the resin layer of the resin tube into the through hole of the resin sealing material and joining the inner surface of the resin sealing material to the outer surface of the resin layer.

Claims

1. A resin tube connecting device connectable to a connected member having a contact surface with a flow path hole, a resin tube having a metal pipe, a resin layer formed on an inner peripheral surface of the metal pipe, and a first flow path surrounded by the resin layer; a resin extension portion that is formed integrally with the resin layer using the same material as the resin layer, and that protrudes from an end of the resin layer in an axial direction and protrudes outward beyond the metal tube in a radial direction of the resin tube; a metal sleeve formed to cover an outer circumferential surface of the metal tube and an outer surface of the resin extension portion, the resin extension portion has a seal surface capable of contacting the contact surface, and a second flow passage communicating with the first flow passage of the resin tube and opening at the seal surface; the seal surface protrudes beyond an end surface of the metal sleeve in the axial direction, The resin extension portion is formed in a columnar shape.

2. 2. The resin tube connection device of claim 1, wherein the maximum length of the contact area between the resin extension portion and the metal sleeve on the outer surface in the axial direction is greater than the thickness of the resin layer in the radial direction, thereby suppressing damage to the resin tube or the resin extension portion when a torsional torque is applied.

3. the end face of the metal sleeve is located between the seal surface and the end face of the metal pipe in the axial direction, and the outer surface of the resin extension portion extends to the end face of the metal pipe in the axial direction, 2. The resin tube connection device according to claim 1, wherein the maximum length of the contact area between the resin extension portion and the metal sleeve on the outer surface corresponds to the distance between the end face of the metal sleeve and the end face of the metal tube in the axial direction.

4. The resin extension portion is formed in a columnar shape having one end surface, another end surface, and the outer surface, 2. The resin tube connecting device according to claim 1, wherein the one end surface of the columnar shape is the sealing surface, and the other end surface of the columnar shape contacts the end surface of the metal tube in the axial direction.

5. A resin tube connecting device connectable to a connected member having a contact surface with a flow path hole, a resin tube having a metal pipe, a resin layer formed on an inner peripheral surface of the metal pipe, and a first flow path surrounded by the resin layer; a resin extension portion that is formed integrally with the resin layer using the same material as the resin layer, and that protrudes from an end of the resin layer in an axial direction and protrudes outward beyond the metal tube in a radial direction of the resin tube; a metal sleeve formed to cover an outer circumferential surface of the metal tube and an outer surface of the resin extension portion, the resin extension portion has a seal surface capable of contacting the contact surface, and a second flow passage communicating with the first flow passage of the resin tube and opening at the seal surface; the seal surface protrudes beyond an end surface of the metal sleeve in the axial direction, an end surface of the metal sleeve is formed flush with an end surface of the metal pipe; the end surface of the metal sleeve has recesses at positions respectively at predetermined distances from an inner circumferential surface and an outer circumferential surface of the metal sleeve, The resin extension portion is an end surface covering portion formed on the end surface of the metal tube and on the end surface of the metal sleeve so as to protrude outward from the metal tube in the radial direction; a fitting portion formed integrally with the end surface covering portion, the fitting portion having the outer surface and fitted into the recess, A resin tube connecting device, wherein the outer surface and the inner surface of the fitting portion are in contact with the metal sleeve within the recess.

6. 2. The resin tube connection device according to claim 1, wherein an area of ​​an opening of the second flow passage in the sealing surface of the resin extension portion is larger than a cross-sectional area of ​​the first flow passage of the resin tube.

7. A method for manufacturing the resin tube connection device according to claim 1, comprising the steps of: Integral molding the resin extension portion and the resin layer by thermoforming; or The manufacturing method includes a step of integrally molding the resin extension portion and the resin layer by thermoforming and compression molding at room temperature.

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