JP2015197200A - Joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint capable of obtaining a high sealing characteristic even if a low fastening torque is applied.SOLUTION: In this invention, when a screw coupling between a joint main body 11 and a nut 12 is fastened, the nut 12 presses a pressed part 13g of a ferrule 13 to cause the pressed part 13g to be entered between the inner circumferential surface 11b of taper and the outer circumferential surface 20a of a pipe 20 while a pushing part 13a depressing an O-ring 14, the O-ring 14 is crushed by the inner circumferential surface 11b of the taper, the outer circumferential surface 20a of the pipe 20 and a pressing part 13c, a raised-up part 13d of the ferrule 13 is raised up, it is rotated around a work point of the inner circumference of a front end part (the pushing part) 13a with the outer circumference of the front end part 13a being applied as a fulcrum point and its is engaged and driven toward the outer circumference of the pipe 20.

Description

  The present invention relates to a joint used for connecting a pipe such as a fluid pipe through which a fluid passes.

  In connection with fluid pipes, various single ferrule type joints have been proposed in order to reduce costs by reducing the number of parts and to facilitate installation work (see Patent Document 1). The joint disclosed in Patent Document 1 has a ferrule and an O-ring, and by tightening the nut, the ferrule presses the O-ring against the joint body and crushes, and the protrusion on the nut side of the ferrule bites into the pipe. It is comprised so that a sealing function may be exhibited.

JP 2001-159482 A

  However, in the joint of Patent Document 1, since the entire O-ring is not configured to enter between the tapered inner peripheral surface of the joint body and the pipe, the crushing cost of the O-ring changes due to variations in the external dimensions of the pipe. Therefore, a stable sealing property cannot be exhibited. Further, since only the ferrule protrusion is bitten, in order to obtain high sealing performance, a very large torque is required for tightening the nut.

  An object of the present invention is to provide a joint capable of obtaining high sealing performance even with a small tightening torque.

  A joint according to one embodiment of the present invention is a joint that is connected to a pipe, and includes a first member having a through hole that receives the pipe, a through hole that receives the pipe, and a central axis of the through hole. A second member threadedly coupled to the first member in alignment with the central axis of the through hole of the first member, a through hole penetrating from the first end to the second end and receiving the tube is formed; The inner axis of the first member, the inner surface of the second member, and the outer surface of the pipe are formed such that the center axis of the through hole coincides with the center axis of the first member and the second member. A ferrule disposed in the storage space, and an annular rubber elastic body disposed between the ferrule and the first member in the storage space, wherein the ferrule includes the first end portion. A pressing portion for pressing the rubber elastic body, a rising portion, and a front A pressed portion that is closer to the second end than the rising portion; and a connecting portion that connects the rising portion and the pressed portion; and the first member includes the rubber elastic body and the ferrule. A tapered inner peripheral surface that is a tapered inner peripheral surface with which the first end can come into contact, and when the screw connection between the first member and the second member is tightened, the second member is attached to the ferrule. By pressing the pressed portion, the pressing portion enters between the tapered inner peripheral surface and the outer peripheral surface of the tube while pressing the rubber elastic body, and the rubber elastic body is inserted into the tapered inner peripheral surface. Crushing by the outer peripheral surface of the tube and the pressing portion, and the rising portion of the ferrule rises, and the inner periphery of the first end rotates with the outer periphery of the first end serving as a fulcrum. And bite toward the outer periphery of the tube It is driven.

  According to the joint of the present invention, high sealing performance can be obtained even with a small tightening torque.

It is sectional drawing of the coupling by this embodiment. It is sectional drawing which shows the state of the joint after attaching a joint to a pipe | tube. It is a figure for demonstrating the operation | movement and effect | action of each part when a coupling is assembled | attached to a pipe | tube. It is a figure for demonstrating the principle by which a ferrule is driven in toward a pipe | tube. It is a figure for demonstrating the principle by which a ferrule is driven in toward a pipe | tube. It is the graph which measured the change to the relative position of the front end part of a ferrule with respect to a pipe | tube when the front end part of a ferrule digs and drives toward the outer periphery of a pipe | tube. It is a figure for demonstrating the modification of the coupling by this embodiment. It is a figure for demonstrating the coupling by another modification.

  An example of an embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a cross-sectional view of the joint according to the present embodiment. Referring to FIG. 1, the joint 10 includes a joint body 11, a nut 12, a ferrule 13, and an O-ring (rubber elastic body) 14 each having a cylindrical shape. The joint is used in connection with a pipe for the purpose of connecting the pipe through which a fluid passes.

  The joint body 11 and the nut 12 are screwed together and can be tightened or loosened. The joint body 11, the nut 12, and the ferrule 13 have a through hole that receives the pipe 20. The joint 10 includes a nut 12 so that the ferrule 13 and the O-ring 14 are housed in a housing space formed by the inner circumferential surface 11 a of the joint body 11, the inner circumferential surface 12 a of the nut 12, and the outer circumferential surface 20 a of the pipe 20. When the pipe 20 is received in the order of the ferrule 13, the O-ring 14, and the joint body 11, and the screw connection between the joint body 11 and the nut 12 is tightened, the pipe 20 is connected.

  The ferrule 13 includes a pressing portion 13c, a rising portion 13d, a bending portion 13e, an intermediate portion 13f, and a pressed portion between the front end portion (first end portion) 13a and the rear end portion (second end portion) 13b. 13g. The thickness of the ferrule 13 is substantially constant from the front end portion 13a to the rear end portion 13b. Here, the joint body 11 side is the front, and the nut 12 side is the rear. The curved portion 13e and the intermediate portion 13f correspond to connection portions.

  Between the front end portion 13a and the rear end portion 13b of the ferrule 13, there is a region having a larger inner diameter than the front end portion 13a and the rear end portion 13b. The pressing portion 13c includes a front end portion 13a, has a thickness substantially equal to the thickness of the O-ring 14 in the radial direction, and the outer periphery of the front end of the pressing portion 13c is rounded. The rising portion 13d is connected to the outer peripheral side of the rear end of the pressing portion 13c, extends along the axial direction, and the inner diameter and the outer diameter are substantially constant. Accordingly, the inner diameter of the rising portion 13d is configured to be larger than the inner diameter of the pressing portion 13c.

  The curved portion 13e is connected to the rear end of the rising portion 13d and is curved so as to protrude outward. Thereby, the bending part 13e contains the part with the largest inner diameter and outer diameter. Further, the bending portion 13e is located near the center of the ferrule 13 in the axial direction. The intermediate portion 13f is connected to the rear end of the curved portion 13e, extends along the axial direction, and the inner diameter and the outer diameter are substantially constant. The inner diameter of the intermediate portion 13f is configured to be larger than the inner diameter of the pressing portion 13c. The pressed portion 13g includes a rear end portion 13b, is connected to the rear end of the intermediate portion 13f, and is configured such that the inner diameter and the outer diameter gradually decrease toward the rear. The innermost diameter of the pressed part 13g is configured to be smaller than the inner diameters of the rising part 13d and the intermediate part 13f. Further, the outer periphery of the rear end of the pressed portion 13g is rounded.

  The O-ring 14 is made of a rubber elastic body and is disposed in front of the ferrule 13.

  The joint body 11 has a tapered inner peripheral surface 11b which is a tapered inner peripheral surface capable of contacting the O-ring 14 and the front end portion 13a of the ferrule 13. The taper inner peripheral surface 11b, the rising portion 13d of the ferrule 13 and the outer peripheral surface of the intermediate portion 13f form a predetermined angle α on a plane passing through the central axis. The taper inner peripheral surface 11b is configured such that the inner diameter increases toward the rear. The angle α may be set to an appropriate value according to the set values of various parameters such as the thickness of the ferrule 13, the length of the rising portion 13d, and the shape of the joint body 11. Further, the width W in the radial direction of the tapered inner peripheral surface 11b is configured to be larger than the thickness of the O-ring 14 and the thickness of the pressing portion 13c.

  The nut 12 includes a coupling portion 12B that is screw-coupled to the joint main body 11, and a protruding portion (fitted portion) 12C that projects inward from the inner peripheral surface 12a of the coupling portion 12B. 12 C of protrusion parts have the press part 12D which presses at least one part of the to-be-pressed part 13g of the ferrule 13, and the notch 12e is formed in the press part 12D. The notch 12e is formed continuously around the inner peripheral surface of the pressing portion 12D. By fitting the pressed portion 13g of the ferrule 13 into the notch 12e, the nut 12 and the ferrule 13 are integrated. The pressed portion 13g is press-fitted into the notch 12e while being elastically deformed, and is fitted. Specifically, when the fitting portion 13f is press-fitted into the notch 12e and the outer peripheral surface of the pressed portion 13g contacts the inner surface of the notched 12e, the pressed portion 13g becomes a protruding portion (fitted portion). ) It is fitted to 12C.

  When the joint body 11 and the nut 12 are finger tight, the ferrule 13 and the O-ring 14 are housed in the housing space, and the rising portion 13d and the intermediate portion 13e are arranged at the outer periphery of the pipe 20 with the curved portion 13e as the center. There is a permissible space 15 that can be raised so as to increase the angle formed by the surface 20a (the rising portion 13d reduces the angle α and the intermediate portion 13f increases the angle α). The finger-tight state is such that the joint body 11 and the O-ring 14, the O-ring 14 and the ferrule 13, and the ferrule 13 and the nut 12 are in contact with each other, but the ferrule 13 is not deformed. It is in a state where the coupling is tightened.

  The central axes of the nut 12, ferrule 13, O-ring 14, and joint body 11 are matched, and the pipe 20 is received in the order of the nut 12, ferrule 13, O-ring 14, joint body 11. When the screw connection between the nut 12 and the nut 12 is tightened with a predetermined tightening torque by a predetermined tightening amount, the tapered inner peripheral surface 11b and the outer peripheral surface 20a of the tube 20 are pressed while the pressing portion 13c presses the O-ring 14 as shown in FIG. The O-ring 14 is crushed by the pressing portion 13c, the tapered inner peripheral surface 11b, and the outer peripheral surface 20a to form a seal, and the front end portion 13a of the ferrule 13 bites into the tube 20 to form a seal. The joint 10 is connected to the pipe 20.

  Hereinafter, the operation and action of each part when the joint 10 is assembled to the pipe 20 will be further described. FIG. 3 is a diagram for explaining the operation and action of each part when the joint is assembled to the pipe.

  As shown in FIG. 3, when the screw connection between the joint body 11 and the nut 12 is tightened, the pressing portion 12D of the nut 12 pushes the pressed portion 13g of the ferrule 13 forward by the force F1 generated in the axial direction. The ferrule 13 whose pressed portion 13g is pressed pushes the front joint body 11 forward via the O-ring 14 accordingly. As a reaction, the ferrule 13 is pushed backward by the joint body 11.

  In the ferrule 13 whose front end portion 13a is pushed rearward and whose pressed portion 13g is pushed forward, the curved portion 13e protrudes outward by the force F2 derived from the force F1, so that the rising portion 13d and the intermediate portion The inner diameter and the outer diameter of 13f increase, and the front end portion 13a and the rear end portion 13b are deformed so as to approach each other. That is, the ferrule 13 bends around the curved portion 13e. At this time, the rising portion 13d rises so as to increase the angle formed with the outer periphery of the tube 20 until the angle of the outer peripheral surface thereof matches the angle of the tapered inner peripheral surface 11b of the joint body 11.

  As the rising portion 13d rises, at the front end portion 13a, the outer peripheral portion that contacts the tapered inner peripheral surface 11b of the joint body 11 is limited by the tapered inner peripheral surface 11b, and the inner peripheral portion that contacts the pipe 20 bites into the pipe. To be driven. In other words, at the front end portion 13a of the ferrule 13, the outer peripheral portion serves as a fulcrum and the inner peripheral portion serves as an action point, and the ferrule 13 is driven into the tube 20 by a strong force according to the lever principle.

  On the other hand, the pressed portion 13g (rear end portion 13b) moves on the outer peripheral surface 20a of the tube 20 without biting into the tube 20. Further, with the rise of the intermediate portion 13f, the fitted state between the pressed portion 13g and the pressing portion 12D is eliminated. Further, since the bending portion 13e is plastically deformed, even if the nut 12 is removed after the fitting state between the pressed portion 13g and the pressing portion 12D is maintained and the joint 10 is assembled to the pipe 20, the ferrule 13 is removed. And the biting state of the ferrule 13 can be confirmed.

  Further, since the deformed ferrule 13 retains some elastic force to return to its original shape, the ferrule 13 and the joint body 11 are pressed against each other, and the ferrule 13 and the nut 12 are pressed against each other. As a result, it is possible to suppress the joint 10 from loosening from the pipe 20 due to vibration or the like. Further, since the elastic deformation of the ferrule 13 disappears when it is returned to the finger tight state, the nut 12 and the ferrule 13 do not pop out by the elastic force when the joint 10 is removed.

  Next, the principle that the ferrule 13 is driven into the tube 20 in this embodiment will be described. 4 and 5 are diagrams for explaining the principle that the ferrule is driven to bite toward the tube. It should be noted that the ferrule biting-in drive hardly changes depending on the presence or absence of the O-ring 14, and therefore the illustration of the O-ring 14 is omitted in FIGS.

  When viewed in a cross section passing through the central axis, the ferrule 13 of the present embodiment, as shown in FIG. 4, is one end in the longitudinal direction of a member 13d ′ simulating a rising portion 13d and a member 13f ′ simulating an intermediate portion 13f. It can be considered that the members are connected to each other at a connection point 13e ′ simulating the curved portion 13e, and further connected to the member 13d ′, the member 13f ′, and an elastic body 13h ′ at an intermediate point. In this structure, the member 13d ′ and the member 13f ′ maintain a predetermined angle by the elastic force of the elastic body 13h ′ when no external force is applied.

  When the joint body 11 restricts the leftward movement of the tip 13a 'of the member 13d' and a force F1 is applied to the member 13f 'in the left direction in the figure, the elastic body 13h' is contracted and the connection point 13e 'is raised upward. The pushing force F2 is derived. As a result, a counterclockwise rotational movement occurs at the tip 13a ′ of the member 13d ′.

  Referring to the enlarged view of the vicinity of the tip 13a ′ shown in FIG. 5, in the state where the entire member 13d ′ is pressed against the pipe 20 and the joint body 11, the tip 13a ′ of the member 13d ′ undergoes a rotational motion, and the fulcrum 13i ′. The action point 13j ′ rotates around the axis and the action point 13j ′ is driven to bite into the tube 20.

  FIG. 6 is a graph obtained by measuring the change in the relative position of the front end of the ferrule with respect to the tube when the front end of the ferrule is driven into the outer periphery of the tube. In FIG. 6, a plurality of graphs indicated by solid lines change the parameter of the change in the position of the front end 13 a when the front end 13 a of the ferrule 13 is driven into the outer periphery of the tube 20. Multiple measurements. A broken line in FIG. 6 is a comparative example showing a change in the position of the front end of the front ferrule located on the joint body side in the double ferrule-type joint.

  In FIG. 6, the horizontal axis indicates the relative position in the axial direction, and the vertical axis indicates the relative displacement in the depth direction. The relative position in the finger tight state is the origin on the horizontal and vertical axes. In the axial direction, the negative value increases as it moves forward. On the vertical axis, the negative value increases as the bite progresses.

  As can be seen from FIG. 6, when the tightening of the screw connection is advanced from the finger tight state with a predetermined torque, the first stage is that the front end portion 13 a of the ferrule 13 is mainly in the axial direction with respect to the tube 20. proceed. However, when it reaches a certain point, the inner periphery of the front end portion 13a of the ferrule 13 bites into the outer periphery of the tube 20, and the front end portion 13a mainly advances in the biting direction according to the lever principle that occurs when the rising portion 13d rises. Migrate to This transition point is the grip point in the figure. At the stage where the front end portion 13a mainly advances in the biting direction, the front end portion 13a is retracted in reverse when viewed in the axial direction. When the rising of the rising portion 13d is completed, the front end portion 13a again shifts to a stage where it mainly advances forward. Thus, when the rising portion 13d rises, the lever principle works with the outer periphery of the front end portion 13a as a fulcrum and the inner periphery of the front end portion 13a as an action point, and at least a part of the screw connection is tightened. In the stage, a phenomenon occurs in which the inner periphery of the front end portion 13a bites toward the outer periphery of the tube 20 while returning to the direction opposite to the axial direction of the force of the nut 12 pushing the ferrule 13 in the axial direction.

  In this way, the front end portion 13a of the ferrule 13 is bitten and driven, so that the ferrule 13 bites into the tube 20 with a strong force, and the sealing performance is exhibited. Further, when the front end portion 13a of the ferrule 13 is bitten and driven while returning to the reverse direction, the space between the ferrule 13 and the pipe 20 is well sealed, and high sealing performance is exhibited. As can be seen from FIG. 6, the front end portion 13a of the ferrule 13 is a pipe having a single ferrule type joint (this embodiment) indicated by a solid line and a depth similar to that of a double ferrule type joint indicated by a broken line. Biting into 20.

  As described above, in this embodiment, when the screw connection between the joint body 11 and the nut 12 is tightened by a predetermined tightening torque by a predetermined tightening amount, the pressing portion 13c pushes the O-ring 14 as shown in FIG. While entering between the tapered inner peripheral surface 11b and the outer peripheral surface 20a of the tube 20, the O-ring 14 is crushed by the pressing portion 13c, the tapered inner peripheral surface 11b and the outer peripheral surface 20a, and the rising portion 13c of the ferrule 13 rises. The inner periphery of the front end portion 13a rotates with the outer periphery of the front end portion 13a as a fulcrum, and is driven to bite toward the outer periphery of the tube 20.

  In this manner, the ferrule 13 is bitten into the pipe 20 while the O-ring 14 is pressed and crushed by the ferrule 13, and the O-ring 14 and the ferrule 13 are configured to tighten the outer periphery of the pipe 20. And since the outer peripheral part becomes a fulcrum and the inner peripheral part becomes an action point, and the ferrule 13 is bitten into the pipe 20 by utilizing the lever principle, the ferrule 13 can be moved with a strong force even with a small tightening torque. The tube 20 can be bitten and the O-ring 14 can be crushed and the tube 20 can be tightened by the O-ring 14. As a result, even if the pipe 20 has a large diameter and the force generated in the axial direction of the pipe 20 due to the pressure of the fluid increases, the joint that can withstand a large axial force by tightening the O-ring 14 and the ferrule 13. 10 can be provided.

  In addition, the O-ring 14 and the ferrule 13 can satisfactorily seal between the pipe 20 and the joint 10, and high sealing performance can be obtained.

  Further, the pressing portion 13 c of the ferrule 13 is configured to enter between the tapered inner peripheral surface 11 b and the outer peripheral surface 20 a of the pipe 20 while pushing the O-ring 14, so that the ferrule 13 and the O-ring 14 tighten the pipe 20. Therefore, even if the outer diameter of the tube 20 varies, the shape of the space formed by the ferrule 13, the tapered inner peripheral surface 11b, and the outer peripheral surface 20a of the tube 20 does not change. Can be prevented. Therefore, the possibility of liquid leakage due to variations in the outer diameter of the tube 20 can be reduced.

  Moreover, since the ferrule 13 has the curved part 13e which curves so that it may protrude outside, when the nut 12 presses the pressed part 13g of the ferrule 13, the ferrule 13 bends about the curved part 13e, and the rising part 13d It is possible to stand up and generate a rotational movement at the front end portion 13a.

  Moreover, since the thickness of the pressing portion 13c in the radial direction has a thickness substantially equal to the thickness of the O-ring 14, the pressing portion 13c causes the O-ring 14 to have a tapered inner peripheral surface 11b and an outer peripheral surface 20a of the tube 20. It can be pushed in between and crushed reliably.

  Also, since the outer periphery of the pressing portion 13c of the ferrule 13 is chamfered, when the rising portion 13d rises, the outer periphery of the pressing portion 13c is pressed against the joint main body 11 and slides on the tapered inner peripheral surface 11b of the joint main body 11, It is difficult to shift on the tube 20 on the inner periphery of the pressing portion 13c, and it is possible to satisfactorily drive in.

  Further, the length of the rising portion 13d is configured to be larger than the thickness of the front end portion 13a (pressing portion 13c) of the ferrule 13. Thus, when the rising portion 13c rises, a strong force is generated on the inner periphery of the front end portion 13a, which is the point of action, in the lever principle where the outer periphery of the front end portion 13a is the fulcrum and the inner periphery is the point of action. The ferrule 13 can bite into the tube 20 with a strong force.

  Further, when the screw connection between the joint body 11 and the nut 12 is tightened, the pressed portion 13g of the ferrule 13 moves along the outer peripheral surface 20a of the pipe 20 and approaches the front end portion 13a. 13 g does not bite into the tube 20. Therefore, the rising portion 13d can be smoothly raised, and the front end portion 13a can be driven into the outer periphery of the tube 20 well, so that the strong bite can be generated at the inner periphery of the front end portion 13a as the action point. Force is generated and a good sealing mechanism is realized.

  The above-described embodiments of the present invention are examples for explaining the present invention, and are not intended to limit the scope of the present invention only to those embodiments. Those skilled in the art can implement the present invention in various other modes without departing from the spirit of the present invention.

  FIG. 7 is a view for explaining a modified example of the ferrule of the joint according to the present embodiment.

  As shown in FIG. 7, the ferrule 113 of the joint 110 according to this modification does not have the curved portion 13e of the ferrule 13, and gradually rises as the rising portion 113d and the intermediate portion 113f move toward the center of the ferrule 13. The inner diameter and the outer diameter are increased, and the outer convex shape is formed.

  According to such a configuration, when the joint body 11 and the nut 12 are tightened, the ferrule 113 bends around the connecting portion between the rising portion 113d and the intermediate portion 113f, and the rising portion 13d rises, so that it rotates to the front end portion 13a. Can generate movement. Moreover, also in this modification, the same effect as said embodiment can be show | played.

  FIG. 8 is a view for explaining a joint according to another modification.

  As shown in FIG. 8, the ferrule 213 of the joint 210 according to this modification has a rising portion 213d and an intermediate portion 213f extending along the axial direction, and is a connecting portion between the rising portion 213d and the intermediate portion 213f. A notch 213e is formed on the inner peripheral surface.

  According to such a configuration, when the joint body 11 and the nut 12 are tightened, the ferrule 213 bends around the notch 213e, the rising portion 13d rises, and rotational motion can be generated at the front end portion 13a. Moreover, also in this modification, the same effect as said embodiment can be show | played.

  Moreover, in said embodiment, although the ferrule 13 and the nut 12 were integrated, it does not need to be integrated.

  In the above-described embodiment, the rising surface 13c of the ferrule 13 has an angle α on the ceiling surface of the storage space formed by the inner peripheral surface of the joint body 11, the inner peripheral surface of the nut 12, and the outer peripheral surface of the pipe 20. It may be in contact with the intermediate portion 13e having an increased outer diameter in a state where it has risen only. This can be realized by designing in advance that the distance between the top of the curved portion 13e of the ferrule 13 and the ceiling surface of the storage space is a predetermined distance in the finger tight state. According to this, when the rising portion 13d rises by an appropriate angle α and a good seal between the ferrule 13 and the pipe 20 is obtained, the top of the ferrule 13 abuts against the ceiling surface of the storage space, and the ferrule 13 is reinforced. As a result, good sealing performance can be maintained. Note that the ceiling surface of the storage space may be constituted by either the joint body 11 or the nut 12. In the present invention, it is not essential that the top of the ferrule 13 abuts on the ceiling surface of the storage space, and the top of the ferrule 13 does not have to abut on the ceiling surface of the storage space.

  In the embodiment of FIG. 1, the nut 12 pushes the pressed portion 13 g of the ferrule 13 in the axial direction, the joint body 11 contacts the front end portion 13 a of the ferrule 13 and the O-ring 14, and the ferrule 13 rises. Although the example which the part 13d stood up toward the taper inner peripheral surface 11b of the coupling main body 11 was shown, this invention is not limited to this example. As another example, the rising portion 13d and the pressed portion 13g of the ferrule 13 may be disposed in reverse. The O-ring 14 is disposed on the rear side (the nut 12 side) of the rising portion 13d. In that case, the nut 12 has a tapered inner peripheral surface that is in contact with the front end portion 13 of the ferrule 13 and is similar to the tapered inner peripheral surface 11b of the joint body 11 in FIG. When the nut 12 pushes the O-ring 14 in the axial direction by the taper inner peripheral surface, the joint body 11 in contact with the pressed portion 13g of the ferrule 13 relatively pushes back the pressed portion 13g. As a result, the ferrule 13 is deformed, and a rotational motion occurs in the front end portion 13a that is in contact with the nut 12. The outer periphery of the front end portion 13a serves as a fulcrum, and the inner periphery serves as an action point. Is driven into the outer periphery of the tube 20. Further, the O-ring 14 is crushed by the tapered inner peripheral surface of the nut 12, the pressing portion 13 c of the ferrule 13, and the pipe 20. In this case, the pressed portion 13g of the ferrule 13 is press-fitted into the joint body 11, and the joint body 11 and the ferrule 13 are integrated.

10, 110, 210: joint, 11: joint body, 12: nut, 13, 113, 213: ferrule, 13a: front end, 13b: rear end, 13c: pressing part, 13d, 113d: rising part, 13e : Curved portion, 13f, 113f: intermediate portion, 13g: pressed portion, 14: O-ring, 20: tube,

Claims (6)

A joint connecting to a pipe,
A first member having a through hole for receiving the tube;
A second member that has a through-hole that receives the tube, and that is screw-coupled to the first member so that the central axis of the through-hole coincides with the central axis of the through-hole of the first member;
A through hole penetrating from the first end portion to the second end portion to receive the tube is formed, and the first member is formed by aligning the central axis of the through hole with the central axis of the first member and the second member. A ferrule disposed in a storage space formed by an inner peripheral surface of the second member, an inner peripheral surface of the second member, and an outer peripheral surface of the pipe;
A rubber elastic body that has an annular shape and is disposed between the ferrule and the first member in the accommodation space;
With
The ferrule includes a pressing portion that includes the first end portion and presses the rubber elastic body, a rising portion, a pressed portion that is closer to the second end portion than the rising portion, the rising portion, and the covered portion. A connecting portion for connecting the pressing portion,
The first member has a tapered inner peripheral surface which is a tapered inner peripheral surface with which the rubber elastic body and the first end of the ferrule can contact,
When the screw connection between the first member and the second member is tightened, the second member presses the pressed portion of the ferrule, so that the pressing portion presses the rubber elastic body while the taper inner circumference is pressed. The rubber elastic body is crushed by the tapered inner peripheral surface, the outer peripheral surface of the tube, and the pressing portion, and the rising portion of the ferrule is raised, A joint that rotates with the outer periphery of the first end portion as a fulcrum and the inner periphery of the first end portion as an action point, and is driven to bite toward the outer periphery of the tube.   The joint according to claim 1, wherein the connection portion includes a bending portion that has an inner diameter and an outer diameter larger than the rising portion and curves so as to protrude outward.   The joint according to claim 1 or 2, wherein a thickness of the pressing portion in a radial direction is substantially equal to a thickness of the rubber elastic body.   The joint according to any one of claims 1 to 3, wherein an outer periphery of the pressing portion is rounded.   The joint according to any one of claims 1 to 4, wherein a length of the rising portion is configured to be greater than a thickness of the first end portion of the ferrule. 6. The device according to claim 1, wherein when the screw connection between the first member and the second member is tightened, the pressed portion moves along the surface of the tube and approaches the first end portion. The joint according to one item.

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