Assembly of resin pipe and metal member and manufacturing method of this assembly

Abstract

To provide an assembly component which enables improvement of durability of a resin pipe in a connection portion between the resin pipe and a metal member while securing sealability of the connection portion, and to provide a manufacturing method of the assembly component.SOLUTION: A circumferential rib 6a is integrally formed on an outer peripheral surface of a resin cylindrical pedestal 4, which protrudes on an outer peripheral surface of a resin pipe 2, as the pedestal 4, an annular seal material 9 is fitted on one end part 8 of a metal member 7, and the one end part 8 is inserted into the pedestal 4 and fixed to interpose the seal material 9 between an outer peripheral surface of the one end part 8 and an inner peripheral surface of the pedestal 4. The outer peripheral surface of the one end part 8 presses the seal material 9 to restrict the seal material 9 from moving to the inner side in a radial direction and moving to the rear end side in a one end part insertion direction. The inner peripheral surface of the pedestal 4 presses the seal material 9 to restrict the seal material 9 from moving to the outer side in the radial direction and moving to the tip side in the one end part insertion direction. The circumferential rib 6a is disposed on an outer peripheral surface of a portion, into which the one end part 8 is inserted, of the pedestal 4.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an assembly of a plastic pipe and a metal member and a method for manufacturing the assembly, and more specifically to an assembly that can improve the durability of the plastic pipe at the connection between the plastic pipe and the metal member while ensuring the sealing property of the connection. [Background technology]

[0002] Metal sensors that detect the pressure and temperature of the fluid flowing through the pipe, metal joints, valves, and the like may be connected to the pipe midway along its length (see, for example, Patent Document 1). For this reason, pedestals for connecting such metal members are provided on the outer circumferential surface of the pipe to protrude therefrom.

[0003] In recent years, plastic pipes have been adopted as piping to reduce weight. Because the plastic base integrated with the plastic pipe is more susceptible to deformation than metal components, there is a high risk of gaps forming at the connection between the two over time, resulting in a loss of sealing. Furthermore, excessive stress may be generated in the plastic base at the connection, making it prone to damage. Therefore, there is room for improvement in improving the durability of the plastic pipe at this connection while ensuring the sealing performance of the connection between the plastic pipe and the metal component. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-268117 Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is to provide an assembly of a resin pipe and a metal member that can improve the durability of the resin pipe at the connection while ensuring the sealing property of the connection between the resin pipe and the metal member, and a method for manufacturing this assembly. [Means for solving the problem]

[0006] In order to achieve the above object, the assembly of the resin pipe and the metal member of the present invention comprises: A pre-manufactured resin pipe having a cylindrical resin base protruding from its outer periphery, and a metal member, On the pedestal, The aforementioned An assembly of a resin pipe into which one end of a metal member is inserted and fixed and a metal member has an annular sealing material fitted onto the one end and interposed between an outer peripheral surface of the one end and an inner peripheral surface of the base, the outer peripheral surface of the one end pressing against the sealing material restricting radial inward movement and movement toward the rear end in the one end insertion direction, and the inner peripheral surface of the base pressing against the sealing material restricting radial outward movement and movement toward the front end in the one end insertion direction, The pre-manufactured resin pipe is The base has a circumferential rib that protrudes outward and continues around the entire periphery of the outer periphery of the portion into which the one end is inserted. (However, this does not include specifications where there is a communication part that connects the inside and outside of the base on the peripheral wall of the part of the base where one end of the metal member is inserted.) .

[0007] The method for manufacturing an assembly of a resin pipe and a metal member according to the present invention includes the steps of: is manufactured A method for manufacturing an assembly of a resin pipe and a metal member, in which one end of a metal member is inserted and fixed into a cylindrical resin seat protruding from the outer circumferential surface of the resin pipe, A circumferential rib that protrudes outward and continues around the entire periphery is integrally formed with the base on the outer peripheral surface of the portion into which the one end of the base is inserted. in advanceThe one end portion, on which an annular sealing material is fitted, is inserted into the pedestal and fixed thereto, thereby interposing the sealing material between the outer peripheral surface of the one end portion and the inner peripheral surface of the pedestal, and the outer peripheral surface of the one end portion presses the sealing material to restrict radial inward movement and movement toward the rear end in the one end insertion direction, and the inner peripheral surface of the pedestal presses the sealing material to restrict radial outward movement and movement toward the front end in the one end insertion direction. (However, this does not include specifications in which a communication part that connects the inside and outside of the base is present on the peripheral wall of the part of the base where one end of the metal member is inserted as the assembly product.) . [Effects of the Invention]

[0008] According to the present invention, the annular seal interposed between the outer peripheral surface of the one end and the inner peripheral surface of the seat is pressed by the outer peripheral surface of the one end to restrict radial inward movement and movement toward the rear end in the insertion direction of the one end, and is pressed by the inner peripheral surface of the seat to restrict radial outward movement and movement toward the front end in the insertion direction of the one end. This seal ensures sufficient sealing at the connection between the plastic pipe and the one end of the metal member. Furthermore, since the outer peripheral surface of the seat where the one end is inserted has the circumferential rib, the stress generated in the seat at the connection between the two is reduced by the circumferential rib. As a result, this is advantageous for improving the durability of the plastic pipe (the seat) at the connection between the two. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is an explanatory diagram illustrating an embodiment of an assembly of a resin pipe and a metal member as viewed from the front. FIG. [Figure 2] FIG. 2 is a view taken along the arrow A in FIG. [Figure 3] 2 is a cross-sectional view of FIG. 1 taken along line B-B. [Figure 4] 2 is an explanatory cross-sectional view showing a state in which the resin pipe and the metal member in FIG. 1 are separated. FIG. [Figure 5] 5 is an explanatory front view illustrating a step of connecting the resin pipe and the metal member in FIG. 4. FIG. [Figure 6]FIG. 10 is an explanatory side view illustrating another embodiment of the assembly. [Figure 7] 7 is a cross-sectional view taken along CC in FIG. 6. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an assembly of a resin pipe and a metal member according to the present invention and a method for manufacturing this assembly will be described based on the embodiments shown in the drawings.

[0011] As shown in Figures 1 to 3, an embodiment of an assembly 1 manufactured by the present invention is formed by connecting and integrating a resin pipe 2 and a metal member 7. In this embodiment, the resin pipe 2 is a straight pipe, but it may also be a bent pipe. The outer diameter of the resin pipe 2 is, for example, about 6 mm to 150 mm, and the inner diameter is, for example, about 4 mm to 146 mm.

[0012] One end 8 of a metal member 7, such as a metal sensor, a metal joint, or a valve, is inserted into a base 4 formed midway along the length of the resin pipe 2 and connected to the resin pipe 2. A ring-shaped sealant 9 is interposed between the outer circumferential surface of the one end 8 and the inner circumferential surface of the base 4 to ensure sealing between the resin pipe 2 (base 4) and the one end 8. The bottom side of the drawing is the leading end side of the one end 8 in the insertion direction of the metal member 7 (hereinafter referred to as the leading end side in the one end insertion direction), and the top side of the drawing is the trailing end side of the one end 8 in the insertion direction (hereinafter referred to as the trailing end side in the one end insertion direction).

[0013] The structure of the assembly 1 will be described in detail below.

[0014] 3, the resin pipe 2 has a conduit 3 that extends through it in the longitudinal direction, and a base flow path 5 that extends in the protruding direction of the base 4 branches off from the conduit 3 midway. The base flow path 5 opens at the protruding end of the base 4. The protruding height t of the base 4 from the outer circumferential surface of the resin pipe 2 is, for example, about 1 mm to 30 mm.

[0015] The base 4 has a shape in which a base large diameter portion 4a, a base expanded diameter portion 4b, and a base small diameter portion 4c are connected from the protruding end side. The outer diameter of the base expanded diameter portion 4b gradually increases from the base small diameter portion 4c toward the base large diameter portion 4a.

[0016] The inner peripheral surface of the base 4 is formed with a step having a flat surface that is parallel to the radial direction of the base 4 (the left-right direction in the drawing) and continues around the entire circumference. A rubber or elastomer seal 9, such as an O-ring, is disposed on the flat surface of this step. More specifically, the step where the seal 9 is disposed is formed near the boundary between the base large-diameter portion 4a and the base expanded-diameter portion 4b, and other steps are formed above and below this step. That is, the inner peripheral surface of the base 4 is formed with steps at a position corresponding to the boundary between the large-diameter portion 8a and the expanded-diameter portion 8b of one end portion 8 (described later), a position corresponding to the boundary between the expanded-diameter portion 8b and the small-diameter portion 8c, and a position corresponding to the tip of the small-diameter portion 8c.

[0017] The base 4 has a circumferential rib 6a on its outer peripheral surface that protrudes outward and continues around the entire circumference. In this embodiment, three circumferential ribs 6a are arranged at intervals in the cylindrical axis direction of the base 4. That is, one circumferential rib 6a is arranged on the base large diameter portion 4a, and two circumferential ribs 6a are arranged on the base small diameter portion 4c.

[0018] At least one circumferential rib 6a may be disposed on each of the base large diameter portion 4a, the base enlarged diameter portion 4b, and the base small diameter portion 4c. The number of circumferential ribs 6a may be, for example, about 1 to 5, but it is preferable that at least one circumferential rib 6a is disposed on the protruding opening end of the base 4. The at least one circumferential rib 6a is disposed on the outer peripheral surface of the portion into which one end 8 of the base 4 is inserted. It is preferable that each circumferential rib 6a is disposed on the outer peripheral surface of the portion into which one end 8 of the base 4 is inserted.

[0019] The amount of protrusion h of each circumferential rib 6a from the outer peripheral surface of the base 4 to the outer circumferential side is preferably 1 mm or more, for example, 1 mm to 10 mm. The width W of each circumferential rib 6a is, for example, 1 mm to 10 mm.

[0020] The cross-sectional shape of the circumferential rib 6a is not limited to a semicircular shape as in this embodiment, and may be a triangular shape, a square shape, or any other polygonal shape, etc. However, it is preferable that the cross-sectional shape of the circumferential rib 6a has no corners, as this cross-sectional shape is advantageous for improving the durability of the circumferential rib 6a.

[0021] Various known resins such as nylon resin (such as nylon 66), polypropylene, and ABS resin are used as the resin for forming the resin pipe 2. The type (specifications) of resin used for the resin pipe 2 is determined based on the performance required for the resin pipe 2. For example, a resin that has excellent durability against the fluid flowing through the pipeline 3, and durability against external impacts, abrasion, ultraviolet rays, etc. is used.

[0022] In the case of a resin pipe 2 that requires high pressure resistance, short fibers (such as glass fibers or carbon fibers) are mixed into the resin for reinforcement in a predetermined ratio (for example, 30% to 40% by mass per 100 parts by mass of resin). The size of the short fibers is, for example, an outer diameter of about 0.001 mm to 1.0 mm and a length of about 0.01 mm to 10 mm.

[0023] The metal member 7 has a flow path 7a that extends through it in the longitudinal direction (insertion direction), and the flow path 7a opens at the leading end of one end 8 in the insertion direction. One end 8 has a shape in which a small diameter portion 8c at the leading end in the insertion direction, a large diameter portion 8a at the rear end in the insertion direction, and an expanded diameter portion 8b whose outer diameter gradually expands from the small diameter portion 8c toward the large diameter portion 8a, which are connected together. The small diameter portion 8c, the expanded diameter portion 8b, and the large diameter portion 8a correspond to the base small diameter portion 4c, the base expanded diameter portion 4b, and the base large diameter portion 4a, respectively.

[0024] The inner peripheral surface of the base small diameter portion 4c and the outer peripheral surface of one end portion 8 are screwed together, whereby the metal member 7 is fixed to the resin pipe 2. The flow path 7a and the pipe line 3 are in communication with each other via the base flow path 5.

[0025] In this assembly 1, the outer peripheral surface of one end 8 (the outer peripheral surface of the expanded diameter portion 8b) that presses against the sealing material 9 restricts the sealing material 9 from moving radially inward and toward the rear end in the one end insertion direction. Also, the inner peripheral surface of the base 4 that presses against the sealing material 9 restricts the sealing material 9 from moving radially outward and toward the front end in the one end insertion direction.

[0026] The outer peripheral surface of one end 8 is not limited to the shape exemplified in this embodiment, and may have any shape that can restrict radial inward movement and movement toward the rear end in the one end insertion direction relative to the sealing material 9. The inner peripheral surface of base 4 is also not limited to the shape exemplified in this embodiment, and may have any shape that can restrict radial outward movement and movement toward the front end in the one end insertion direction relative to the sealing material 9. For example, instead of the expanding diameter portion 8b, one end 8 may have a shape that employs an outer peripheral surface that extends parallel to the radial direction (left and right direction in the drawing) of base 4, whose diameter expands from small diameter portion 8c to large diameter portion 8a.

[0027] An example of the procedure of the manufacturing method of the present invention for manufacturing the assembly 1 will be described below.

[0028] To manufacture the assembly 1 illustrated in FIGS. 1 to 3, a plastic pipe 2 and a metal member 7 are prepared as illustrated in FIG. 4. The plastic pipe 2 is manufactured by a known molding method such as injection molding. The base 4 is manufactured as an integral part of the plastic pipe 2. Therefore, the circumferential rib 6a is also molded integrally with the plastic pipe 2 (base 4). Therefore, the entire plastic pipe 2 is basically made of the same resin, and if short fibers are mixed into that resin, the short fibers are mixed not only in the peripheral wall portion of the conduit 3 of the plastic pipe 2, but also in the base 4 and the circumferential rib 6a. In addition, the circumferential rib 6a is formed integrally with the base 4 on the outer peripheral surface of the portion where one end 8 of the base 4 is inserted.

[0029] Next, as shown in Fig. 5, one end 8 of the metal member 7 fitted with the sealing material 9 is inserted into the cylindrical pedestal 4. The threaded portions on the outer circumferential surface of the one end 8 and the inner circumferential surface of the pedestal 4 are screwed together, and the one end 8 is inserted a predetermined length into the pedestal 4, whereby the two are connected and fixed together as shown in Fig. 3.

[0030] In this assembly 1, the sealing material 9 interposed between the outer peripheral surface of the one end 8 and the inner peripheral surface of the base 4 is pressed by the outer peripheral surface of the one end 8, restricting its movement inward in the radial direction and toward the rear end in the direction of inserting the one end. The sealing material 9 is also pressed by the inner peripheral surface of the base 4, restricting its movement outward in the radial direction and toward the front end in the direction of inserting the one end. As a result, the pressed sealing material 9 is restricted from moving in directions surrounded by all four sides in cross section, and this sealing material 9 can ensure sufficient sealing of the connection between the plastic pipe 2 and the one end 8.

[0031] The inner peripheral surface of the base 4 is pressed by the sealing material 9 pressed by the one end 8, but as in this embodiment, the sealing material 9 is pressed by the outer peripheral surface (inclined surface) of the expanded diameter portion 8b. This prevents the inner peripheral surface of the base 4 from being excessively pressed either radially outward or toward the tip end in the insertion direction of the one end. This is advantageous in preventing excessive stress from being concentrated on the base 4. The inclination angle of the expanded diameter portion 8b with respect to the extension direction of the one end 8 (the vertical direction in the drawing) may be, for example, 30° to 60° (approximately 45°).

[0032] Normally, excessive stress is likely to occur in the portion where one end 8 of the base 4 is inserted, but this assembly 1 has a circumferential rib 6a on the outer periphery of this portion, so the stress occurring in the base 4 at the connection between the two is reduced by the circumferential rib 6a. As a result, this is advantageous in improving the durability of the resin pipe 2 (base 4) at the connection between the two.

[0033] The protruding open end of the base 4 is a free end, so it is prone to large stress and is likely to be the position where maximum stress occurs in the base 4. Therefore, by providing the circumferential rib 6a in this portion, the stress in this portion is dispersed, and it is possible to reduce the maximum stress occurring in the base 4 to, for example, 50% or less.

[0034] As in this embodiment, it is preferable to position the protruding opening end of the pedestal 4 somewhat (for example, 5 mm or more) above the upper end of the sealing material 9. By separating the protruding opening end from the sealing material 9 in this way, it is advantageous to reduce stress generated at the protruding opening end of the pedestal 4, and also to suppress deformation and damage to the protruding opening end.

[0035] When the internal pressure of the resin pipe 2 is 30 MPa or higher, the service life of the resin pipe 2 tends to be shorter, but application of the present invention makes it possible to extend the service life. An example of a resin pipe 2 with an internal pressure of 3.5 MPa or higher (or 30 MPa or higher) is a pipe that carries the refrigerant of an air conditioner installed in an automobile.

[0036] Furthermore, if the resin pipe 2 (base 4) is too hard, it will be disadvantageous in preventing damage over time, so it needs to have a moderate degree of flexibility. Therefore, it is desirable to form the resin pipe 2 (base 4) from, for example, 66 nylon, with short fibers mixed in for reinforcement.

[0037] As in another embodiment of the assembly 1 illustrated in Figures 6 and 7, in addition to the circumferential ribs 6a, it is also possible to have vertical ribs 6b connected to the circumferential ribs 6a and extending in the axial direction of the base 4. At least three vertical ribs 6b are arranged at equal intervals around the circumferential direction of the base 4. For example, four to twelve vertical ribs 6b are arranged at equal intervals around the circumferential direction.

[0038] Each of the vertical ribs 6b is set to substantially the same specifications. It is preferable that the vertical rib 6b extends over the entire length of the portion where one end 8 of the base 4 is inserted. The amount of protrusion h of the vertical rib 6b from the outer peripheral surface of the base 4 toward the outer periphery is preferably 2 mm or more, and may be less than the amount of protrusion h of the circumferential rib 6a. The width W of the vertical rib 6b is approximately the same as the width W of the circumferential rib 6a.

[0039] By providing the above-mentioned vertical ribs 6b in addition to the circumferential ribs 6a, it is advantageous to further improve the durability of the resin pipe 2 (base 4), which is more advantageous in ensuring the sealing performance of the connection portion between the resin pipe 2 (base 4) and the one end 8 of the metal member 7. [Explanation of symbols]

[0040] 1 Assembly 2. Resin pipe 3 conduit 4 Pedestal 4a Large diameter base part 4b Base expansion part 4c Small diameter base 5 Pedestal channel 6a Circumferential rib 6b vertical rib 7 Metallic parts 7a Flow path 8 One end 8a Large diameter part 8b Expanded diameter part 8c Small diameter section 9 Sealing material

Claims

1. An assembly of a resin pipe and a metal member, comprising a pre-manufactured resin pipe having a cylindrical resin base protruding from its outer periphery, and a metal member, one end of the metal member being inserted into and fixed to the base, an annular sealing material fitted onto the one end portion and interposed between an outer peripheral surface of the one end portion and an inner peripheral surface of the base, the outer peripheral surface of the one end portion pressing against the sealing material restricting radial inward movement and movement toward the rear end in the one end insertion direction, and the inner peripheral surface of the base pressing against the sealing material restricting radial outward movement and movement toward the front end in the one end insertion direction, An assembly of a resin pipe and a metal member, characterized in that the pre-manufactured resin pipe has a circumferential rib that protrudes outward and continues around the entire circumference on the outer surface of the part where the one end of the base is inserted (excluding specifications in which a communication portion that connects the inside and outside of the base is present on the peripheral wall of the part where the one end of the metal member of the base is inserted).

2. 2. The assembly according to claim 1, wherein at least one of the circumferential ribs is arranged at the end of the protruding opening of the base, the circumferential rib arranged closest to the protruding opening tip in the height direction of the base is located at a position recessed below the protruding opening tip of the base, and the sealing material is located below the circumferential rib arranged closest to the protruding opening tip.

3. 3. The assembly according to claim 1, wherein a plurality of the circumferential ribs are arranged at intervals in the axial direction of the base.

4. An assembly product described in any of claims 1 to 3, wherein the pre-manufactured plastic tube has at least three vertical ribs spaced equally circumferentially on the outer surface of the portion into which the one end of the base is inserted, protruding outward and extending in the axial direction of the base.

5. the one end portion has a shape in which a small diameter portion on a leading end side in the insertion direction, a large diameter portion on a trailing end side in the insertion direction, and an expanding diameter portion whose outer diameter gradually expands from the small diameter portion toward the large diameter portion, and the small diameter portion is connected to the large diameter portion; An assembly product according to any one of claims 1 to 4, wherein the base has a base small diameter portion corresponding to the small diameter portion, a base large diameter portion corresponding to the large diameter portion, and a base expanded diameter portion corresponding to the expanded diameter portion, and the outer surface of the expanded diameter portion presses the sealing material, restricting radial inward movement of the sealing material and movement of the one end toward the rear end in the insertion direction.

6. A method for manufacturing an assembly of a resin pipe and a metal member, in which one end of a metal member is inserted and fixed into a cylindrical resin base protruding from the outer periphery of a pre-manufactured resin pipe, a circumferential rib that protrudes outward and continues around the entire periphery in the circumferential direction is formed integrally with the base on an outer peripheral surface of a portion of the base into which the one end is inserted, A method for manufacturing an assembly of a plastic pipe and a metal member, characterized in that by inserting and fixing the one end, on which an annular sealing material is fitted, into the base, the sealing material is interposed between the outer peripheral surface of the one end and the inner peripheral surface of the base, the outer peripheral surface of the one end presses the sealing material to restrict radial inward movement and movement toward the rear end in the direction of insertion of the one end, and the inner peripheral surface of the base presses the sealing material to restrict radial outward movement and movement toward the front end in the direction of insertion of the one end (however, this does not apply to specifications in which the assembly has a communication portion connecting the inside and outside of the base on the peripheral wall of the portion of the base where the one end of the metal member is inserted).

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