Pipe fittings

Abstract

The object of the present invention is to provide a pipe joint that can sufficiently restrict the withdrawal of the pipe body. [Solution] A pipe joint for connecting pipes, comprising: a cylindrical joint body having an opening into which the pipe is inserted, into which the pipe is inserted to the rear through the opening; a cylindrical cap member assembled to the opening; and a lock ring formed in an annular shape centered on the axial direction of the joint body, having claws that engage with the outer surface of the pipe inserted into the joint body to restrict the removal of the pipe, wherein the claws are formed to be inclined toward the rear as the inner diameter of the annular shape increases, and the cap member is positioned on the front side of the claws and has a claw support surface that contacts the claws from the front when the claws deform toward the front, the claw support surface is formed to be inclined toward the rear as the inner diameter increases.

Description

Technical Field

[0004] , , , , , , , ,

[0001] The present invention relates to a pipe joint, and particularly to a pipe joint provided with a lock ring for restricting the withdrawal of an inserted pipe body.

Background Art

[0002] As a pipe joint of this type, the technique described in Patent Document 1 below has been proposed. As shown in FIG. 7, this pipe joint 101 includes a joint body 103 having a stepped surface that abuts against the innermost end of the pipe body at the inner back portion, a cylindrical cap member 104 that is assembled to the opening of the joint body 103 by screw fastening, and a lock ring 105 that is accommodated in the lock ring accommodation portion of the joint body 103. In this pipe joint 101, the pipe bodies 2A and 2B are inserted in a state where the joint body 103 and the cap member 104 are assembled.

[0003] As shown in FIGS. 8(a) and 8(b), the lock ring 105 includes an annular flange 150 along the axial direction, an annular claw holding portion 151 formed by bending from the end of the flange 150 toward the center side, and a plurality of claws 152 formed by bending on the inner surface side of the claw holding portion 151. Further, the lock ring 105 is arranged in two side by side on the back side and the front side of the joint body 103 in a state where the flange 150 abuts against the inner surface of the lock ring accommodation portion and the claws 152 extend deeper toward the inner diameter side, and is sandwiched by the locking surface of the lock ring accommodation portion and the pressing surface of the cap member 104 (see FIG. 7). When a pulling force acts on the pipe bodies 2A and 2B inserted into the pipe joint 101, the claws 152 of the lock ring 105 bite into the outer surface of the pipe bodies 2A and 2B, so that the withdrawal of the pipe bodies 2A and 2B from the pipe joint 101 is restricted.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the case of the lock ring located at the rear, its flange is held and fixed between the flange of the lock ring on the front side and the locking surface of the lock ring housing. Therefore, when an outward pulling force is applied to the pipe, not only the claws of the lock ring but also the claw holding part itself deforms, resulting in insufficient engagement of the claws with the pipe and inadequate restriction of the pipe's outward pulling.

[0006] Therefore, the object of the present invention is to provide a pipe joint that can sufficiently restrict the withdrawal of the pipe body. [Means for solving the problem]

[0007] The pipe joint of this invention is a pipe joint for connecting pipe bodies, comprising: a cylindrical joint body having an opening into which the pipe body is inserted, into which the pipe body is inserted toward the rear through the opening; a cylindrical cap member assembled to the opening; and a lock ring formed in an annular shape centered on the axial direction of the joint body, having claws that engage with the outer surface of the pipe body inserted into the joint body to restrict the removal of the pipe body, wherein the claws are formed to be inclined toward the rear as the inner diameter of the annular shape increases, and the cap member is positioned on the front side of the claws and has a claw support surface that contacts the claws from the front when the claws deform toward the front, and the claw support surface is formed to be inclined toward the rear as the inner diameter increases.

[0008] With this configuration, the claw support surface of the cap member contacts the claw of the lock ring from the front side. Therefore, even if a force is applied to the lock ring toward the front and the claw deforms, it will still contact the claw support surface, thus suppressing claw deformation. As a result, the locking of the claw against the outer surface of the pipe can be maintained, and the pulling out of the pipe is sufficiently restricted.

[0009] Furthermore, in the pipe joint, the lock ring may be provided with a claw-holding portion extending outward from the diameter of the claw, the cap member may be provided with a pressing surface positioned in front of the claw-holding portion, and the claw support surface may be formed to be inclined so as the diameter increases from the inner edge of the pressing surface toward the inner side.

[0010] With this configuration, the pressing surface of the cap member contacts the claw-holding portion of the lock ring from the front side. Therefore, even if a force is applied to the lock ring toward the front, the claw-holding portion contacts the pressing surface, thus preventing the claw-holding portion from shifting toward the front.

[0011] Furthermore, in the pipe joint, the cap member may be provided with a claw receiving surface that extends inward from the inward edge of the claw support surface.

[0012] With this configuration, since the claw receiving surface of the cap member extends inward from the inner diameter edge of the claw support surface, even if a force is applied to the lock ring toward the front and the claw deforms toward the front, the deformed claw can be supported by the claw receiving surface. [Effects of the Invention]

[0013] Based on the above, the present invention provides a pipe joint that can sufficiently restrict the withdrawal of the pipe body. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a partially broken side view of the pipe joint according to this embodiment. [Figure 2] Figure 2 is an enlarged view of the main part of Figure 1. [Figure 3] Figure 3 is an enlarged view of the area around the outer diameter end of the claw contact ring in a partially fractured side view of a modified pipe joint. [Figure 4] Figure 4 is a partially fractured side view of a pipe joint according to a modified example. [Figure 5] Figure 5 is an enlarged view of the main part of Figure 4. [Figure 6]Figure 6 is an enlarged view of the area around the outer diameter end of the claw contact ring in a partially fractured side view of a modified pipe joint. [Figure 7] Figure 7 is a cross-sectional side view of a conventional pipe joint. [Figure 8] Figure 8 is a separate view of the lock ring of the pipe fitting, where Figure 8(a) is a side view and Figure 8(b) is a front view. [Modes for carrying out the invention]

[0015] Hereinafter, a pipe joint according to one embodiment of the present invention will be described with reference to Figures 1 and 2. The pipe joint 1 according to this embodiment connects pipes and is suitably used to connect medical gas copper pipes, refrigerant gas copper pipes, and the like, which are examples of pipes. It should be noted that these medical gases, refrigerants including both gases and liquids, are generally known to be at high pressure compared to, for example, the water pressure of tap water.

[0016] As shown in Figure 1, the pipe joint 1 is a pipe joint that connects a pair of pipe bodies 2. The pipe joint 1 also comprises a joint body 3, a cap member 4, and a plurality of locking rings 5. Furthermore, in this embodiment, the pipe joint 1 includes a claw contact ring 6. In order to connect the pipe bodies 2 to be connected, the pipe joint 1 is configured as a pair and as a single unit at the central position along the axial direction of the pipe bodies 2, i.e., the longitudinal direction. For this reason, in the following description, the description of one side of the pipe joint 7 relative to the central position will also serve to describe the configuration of the other side.

[0017] Although the pipe joint section 7 on one side and the pipe joint section 7 on the other side have a symmetrical configuration and an integrated joint body 3, in the following description, even if the joint body 3 has a symmetrical structure and is integrated, when it is referred to as the joint body 3 in the description of the pipe joint section 7 on one side, it refers to the joint body 3 in the area occupied by the pipe joint section 7 on one side. Furthermore, the symbols attached to each part of the pipe joint section 7 on one side are assumed to be attached to the same part of the pipe joint section 7 on the other side, and the symbols attached to each part of the pipe joint section 7 on one side are assumed to be attached to the same part of the pipe joint section 7 on the other side.

[0018] The configuration of the pipe joint portion 7 on one side will be described below. As shown in FIG. 2, the pipe joint portion 7 includes a joint body 3, a cap member 4, a pair of lock rings 5, and a claw contact ring 6. In the pipe joint portion 7, the pair of lock rings 5 includes a rear lock ring 5C disposed on the rear side of the joint body 3 and a front lock ring 5D disposed side by side with the rear lock ring 5C on the front side of the joint body 3. Further, the pipe joint portion 7 of the present embodiment includes a seal ring 8 (see FIG. 1).

[0019] The joint body 3 is a cylindrical portion provided with an opening 30 into which the pipe body 2A is inserted, and the pipe body 2A is inserted into the rear side through the opening 30. The joint body 3 of the present embodiment is formed in a cylindrical shape having a main body side insertion space 31 inside. Further, the joint body 3 integrally includes a main body large diameter portion 32 which is the front side where the insertion of the pipe body 2 starts, that is, the left side portion in FIG. 1, and a main body small diameter portion 33 which is the rear side where the insertion of the pipe body 2 ends, that is, the right side portion in FIG. 1.

[0020] Note that the joint body 3 is made of metal, resin, a composite pipe body of metal and resin, etc. The pipe joint 1 of the present embodiment is made of metal.

[0021] The opening 30 is a portion for inserting the region located on the rear side of the cap member 4. The opening 30 is defined by the inner surface of the main body large diameter portion 32.

[0022] The main body side insertion space 31 is formed to communicate with the rear side of the opening 30. The rear end of the main body side insertion space 31 has a reduced diameter. Further, the main body side insertion space 31 has a lock ring accommodation portion 310 at the end on the opening 30 side, specifically, the front end.

[0023] The lock ring housing portion 310 is formed to have a smaller diameter than the opening 30 and a larger diameter than the inner end of the insertion space 31 on the main body side. Furthermore, the diameter of the lock ring housing portion 310 is set to be slightly larger than the outer diameter of the lock ring 5, so that the lock ring 5 can be accommodated in the lock ring housing portion 310. The length of the lock ring housing portion 310 in the axial direction of the joint body 3 is set to accommodate a pair of lock rings 5.

[0024] The main body's large-diameter portion 32 is formed to have a larger diameter than the main body's small-diameter portion 33. In this embodiment, the main body's large-diameter portion 32 is cylindrical in shape, with the same outer diameter in all directions, including the axial direction of the joint body 3, i.e., the depth direction and the left-right direction in Figure 1. A female thread is formed on a part of the inner surface of the main body's large-diameter portion 32. An annular main body-side large-diameter seal housing portion 320 is formed on the inner surface on the front side of the main body's large-diameter portion 32, which houses a seal ring 8, for example, a large-diameter seal ring 80. The main body's large-diameter portion 32 also has a main body-side first contact surface 321 that contacts the cap member 4. The main body-side first contact surface 321 is the front end face of the main body's large-diameter portion 32.

[0025] The main body small diameter portion 33 is formed to have a smaller diameter than the main body large diameter portion 32. In this embodiment, the main body small diameter portion 33 includes a first main body small diameter portion 34 located on the front side and adjacent to the main body large diameter portion 32, and a second main body small diameter portion 35 located on the rear side and adjacent to the first main body small diameter portion 34.

[0026] The first small-diameter portion 34 of the main body in this embodiment is a tapered cylindrical shape in which the outer diameter decreases towards the rear. The first small-diameter portion 34 has a second contact surface 340 on the main body side that contacts the cap member 4 (see Figure 2). The first small-diameter portion 34 also has a locking surface 341 that engages with the rear lock ring 5C from the rear side. Furthermore, the first small-diameter portion 34 is located on the outer diameter of the rear lock ring 5C and the front lock ring 5D, and has a main body side opposing surface 342 that faces the rear lock ring 5C and the front lock ring 5D.

[0027] In the first small-diameter portion 34 of the main body of this embodiment, the locking surface 341 and the opposing surface 342 on the main body side define the lock ring housing portion 310. The second contact surface 340 on the main body side is, for example, a surface perpendicular to the axial direction of the joint body 3. The locking surface 341 is, for example, a surface perpendicular to the axial direction of the joint body 3. The inner diameter portion of the locking surface 341 is chamfered.

[0028] The opposing surface 342 on the main body side extends towards the front from the outer diameter edge of the locking surface 341. Furthermore, the opposing surface 342 on the main body side extends towards the back from the inner diameter edge of the second contact surface 340 on the main body side. Additionally, the opposing surface 342 on the main body side is, for example, a surface extending in the axial direction of the joint body 3.

[0029] The second main body small diameter section 35 has an annular stepped surface 350 that abuts against the innermost end surface 20 of the pipe body 2 into which it is inserted (see Figure 1). The second main body small diameter section 35 also has a stepped wall 351 that is formed to reduce in diameter at the central position in the axial direction of the joint body 3. Furthermore, the second main body small diameter section 35 has an extended surface 352 that extends forward from the stepped surface 350.

[0030] In this embodiment, the stepped surface 350 is a surface perpendicular to the axial direction of the joint body 3. Furthermore, the stepped surface 350 is a side surface of the stepped wall 351.

[0031] The extension surface 352 is inclined with respect to the stepped surface 350. Furthermore, the extension surface 352 extends inward from the inner edge of the locking surface 341. In this embodiment, the extension surface 352 extends in the axial direction of the joint body 3. Additionally, the extension surface 352 is positioned radially outward from the outer circumferential surface of the pipe body 2.

[0032] The cap member 4 is a cylindrical member that is assembled into the opening 30 of the joint body 3. The cap member 4 is also positioned in front of the claws 50 of the lock ring 5. In this embodiment, the cap member 4 is assembled into the opening 30 by screw fastening. The cap member 4 is made of, for example, metal. The cap member 4 is formed in a cylindrical shape with an internal cap-side insertion space 40. The cap-side insertion space 40 communicates with the body-side insertion space 31 when the cap member 4 is assembled to the joint body 3.

[0033] The cap member 4 has a reduced-diameter portion 41 which is the front end, a large-diameter cap portion 42 integrally formed on the rear side of the reduced-diameter portion 41, and a small-diameter cap portion 43 integrally formed on the rear side of the large-diameter cap portion 42. The cap member 4 can be made of metal or resin, and in this embodiment, the cap member 4 is made of metal.

[0034] The outer surface of the contraction portion 41 is formed in a conical shape by being contracted toward the front. An auxiliary seal housing portion 410 is formed on the inner surface of the contraction portion 41 for housing a seal ring 8, for example, an auxiliary seal ring 81. The auxiliary seal ring 81 contacts the outer surface of the pipe body 2 and helps to prevent condensation that occurs on the outer surface of the pipe joint 1 outside the pipe body 2 from entering the inside of the pipe joint 1.

[0035] The large-diameter cap portion 42 is the part that is gripped by a tool. The cap member 4 is screwed onto the joint body 3 by gripping the large-diameter cap portion 42 with a tool and rotating it. The large-diameter cap portion 42 has a cap-side first contact surface 421 that contacts the body-side first contact surface 321 of the body-side large-diameter portion 32.

[0036] The first contact surface 421 on the cap side is a surface perpendicular to the axial direction of the joint body 3. Furthermore, the first contact surface 421 on the cap side is an annular surface.

[0037] The small-diameter portion 43 of the cap is formed to have a smaller diameter than the large-diameter portion 42 of the cap. Furthermore, the small-diameter portion 43 of the cap is integrally formed with the large-diameter portion 42 of the cap via the first contact surface 421 on the cap side.

[0038] Furthermore, the small diameter portion 43 of the cap has a small diameter portion rear end face 44, which is the rear end face. The small diameter portion rear end face 44 is an annular surface. Also, as shown in Figure 2, the length of the small diameter portion rear end face 44 in the radial direction is set to be longer than that of the second contact surface 340 on the main body side.

[0039] In this embodiment, the rear end face 44 of the small diameter portion is provided with a pressing surface 440 positioned on the front side of the claw holding portion 51 of the lock ring 5. The rear end face 44 of the small diameter portion is also provided with a claw support surface 441 that contacts the claw 50 from the front side when the claw 50 deforms toward the front. Furthermore, the rear end face 44 of the small diameter portion is provided with a claw receiving surface 442 that extends inward from the inward edge 441E of the claw support surface 441.

[0040] Furthermore, the inner end face 44 of the small diameter portion has a cap-side second contact surface 443 that contacts the body-side second contact surface 340 of the joint body 3. On the inner end face 44 of the small diameter portion, an annular recess 444 is formed between the pressing surface 440 and the cap-side second contact surface 443.

[0041] The pressing surface 440 presses the front lock ring 5D from the front. The pressing surface 440 is also positioned at a distance from the locking surface 341 of the joint body 3 in the axial direction of the joint body 3. In this embodiment, the pressing surface 440 is a surface parallel to the locking surface 341. In addition, the pressing surface 440 is, for example, a surface perpendicular to the axial direction of the joint body 3. The outer diameter portion of the pressing surface 440 in this embodiment is chamfered.

[0042] The claw support surface 441 is formed with an inclination that increases towards the back as the diameter increases. In this embodiment, the claw support surface 441 is formed with an inclination that increases towards the back as the diameter increases from the inner edge 440E of the pressing surface 440. That is, the connection point between the claw support surface 441 and the pressing surface 440 is the inner edge 440E. The inclination angle of the claw support surface 441 with respect to the locking surface 341 of the joint body 3 is the same in all parts, but may differ in some parts. Also, when an outward pulling force is applied to the pipe body 2, the claw support surface 441, together with the pressing surface 440, comes into contact with the front lock ring 5D.

[0043] The claw receiving surface 442 is a surface perpendicular to the axial direction of the joint body 3. In this embodiment, the radial dimensions of the claw receiving surface 442 are approximately the same as the radial dimensions of the claw support surface 441, but they may be different. Furthermore, when an outward pulling force is applied to the pipe body 2 and the claw 50 of the front lock ring 5D is deformed toward the front, the claw receiving surface 442 contacts the deformed claw 50. At this time, the radially inner edge 441E of the claw support surface 441, which is the boundary between the claw receiving surface 442 and the claw support surface 441, becomes a fulcrum where the radially inner portion of the claw 50 bends relative to its base. Also, radially, the radially inner edge 442E of the claw receiving surface 442 is located at the same position as the radially inner edge 341E of the locking surface 341. Furthermore, the inner diameter edge of the locking surface 341 is used as the inner diameter edge before chamfering is applied to this portion, that is, the inner diameter edge as it would be if chamfering were not applied.

[0044] The second contact surface 443 on the cap side is machined to be, for example, a smooth surface. Furthermore, the second contact surface 443 on the cap side is positioned on the stepped surface 350 side and on the inside relative to the male thread of the large diameter portion 32 of the main body of the joint body 3. In this embodiment, the outer and inner diameter portions of the second contact surface 443 on the cap side are chamfered.

[0045] The small-diameter portion 43 of the cap in this embodiment has a guide surface 434 that extends towards the front from the inner diameter edge 442E of the claw receiving surface 442. The guide surface 434 extends, for example, in the axial direction of the joint body 3. Furthermore, the guide surface 434 is positioned radially outward from the outer circumferential surface of the pipe body 2. In this embodiment, when the pipe body 2 is pulled out in the tensile direction, or the pressing side in Figure 2, the deformed claw 50 is prevented from deforming further once it is facing radially from the fulcrum, and thus bites into the pipe body 2. As a result, the tensile force is increased at the inner diameter edge 442E of the claw receiving surface 442, which is the boundary between the guide surface 434 and the claw receiving surface 442.

[0046] As shown in Figure 1, in this embodiment, a cap-side large-diameter seal housing portion 420 is formed on the front side of the outer surface of the small-diameter cap portion 43, which accommodates the large-diameter seal ring 80 on its inner diameter side. On the outer surface of the small-diameter cap portion 43, a male thread is formed in the portion behind the cap-side large-diameter seal housing portion 420, which screws into the female thread of the large-diameter body portion 32 of the joint body 3.

[0047] An annular cap-side small-diameter seal housing portion 435 is formed on the inner surface of the cap's small-diameter portion 43 for housing a seal ring 8, for example, a small-diameter seal ring 82. The cap-side small-diameter seal housing portion 435 is spaced apart in the axial direction of the joint body 3.

[0048] In this embodiment of the pipe fitting 1, the pipe fitting section 7 with the above configuration is configured as a pair, symmetrically arranged, and as an integrated structure. In the pipe fitting 1, the pair of lock rings 5 ​​are housed in the fitting body 3, aligned in the axial direction of the fitting body 3, with the flange portion 52 located on the inner diameter side of the inner surface of the fitting body 3 and the claws 50 extending further inward towards the inner diameter side. All the seal rings 8 are positioned on the front side of the pair of lock rings 5. In the cap member 4, the small diameter seal ring 82 is fitted into the small diameter seal housing portion 435 on the cap side, and the large diameter seal ring 80 is fitted into the large diameter seal housing portion 420 on the cap side, with its inner diameter portion attached. With each component attached to the fitting body 3 and the cap member 4 in this manner, the small diameter cap portion 43 of the cap member 4 is inserted into the opening 30 of the fitting body 3, and the fitting is assembled by screw fastening the male and female threads. As a result, the joint body 3 and the cap member 4 are integrated, and the insertion space 31 on the body side and the insertion space 40 on the cap side are connected, forming the insertion space for the pipe body 2.

[0049] When assembling the cap member 4 to the opening 30 of the joint body 3 by screw fastening of the male and female threads, the large diameter portion 42 of the cap should be gripped with a tool, and the cap member 4 should be rotated to tighten it to the joint body 3. When this is done, the outer diameter portion of the large diameter seal ring 80 will be housed in the large diameter seal housing portion 320 on the main body side.

[0050] Furthermore, the large-diameter seal ring 80 is squeezed and compressed between the outer surface of the large-diameter seal housing portion 420 on the cap side and the inner surface of the large-diameter seal housing portion 320 on the main body side. As a result, the gap between the inner surface of the large-diameter portion 32 of the main body and the outer surface of the small-diameter portion 43 of the cap is sealed in the axially outward direction with respect to the threaded portion of the male and female threads.

[0051] The pair of lock rings 5 ​​are arranged side by side in the lock ring housing 310 so as to contact the joint body 3 in the axial direction. Since the pair of lock rings 5 ​​have the same configuration, the description of the configuration of one lock ring 5 will be used to describe the other lock ring 5.

[0052] The lock ring 5 is formed in an annular shape centered on the axial direction of the joint body 3. Furthermore, as shown in Figure 2, the lock ring 5 has claws 50 that engage with the outer circumferential surface of the pipe 2 inserted into the joint body 3, thereby restricting the removal of the pipe. In this embodiment, the lock ring 5 has a claw-holding portion 51 extending outward from the claws 50. The lock ring 5 also has an annular flange 52 centered on the axial direction of the joint body 3. The lock ring 5 is provided with an annular space 53 surrounded by the flange 52, the claw-holding portion 51, and the claws 50.

[0053] The thickness of the lock ring 5 in this embodiment is equal at all points. Furthermore, the lock ring 5 in this embodiment is made of metal.

[0054] In this embodiment, the flange 52 extends in the axial direction of the joint body 3. The outer flange surface 521, located on the radially outer side of the flange 52, is, for example, a plane extending in this axial direction. The inner flange surface 522, located on the radially inner side of the flange 52, is, for example, a plane extending in this axial direction. Both the outer flange surface 521 and the inner flange surface 522 have chamfers on the front side.

[0055] The claw holding portion 51 of this embodiment extends in a direction perpendicular to the axial direction of the joint body 3. The claw holding portion 51 is an annular portion formed by bending the flange 52 from the end towards the center. The rear claw holding surface 510, located on the rear side of the claw holding portion 51, is, for example, a plane extending in a direction perpendicular to this axial direction. The front claw holding surface 511, located on the front side of the claw holding portion 51, is, for example, a plane extending in a direction perpendicular to this axial direction. The inner diameter portions of both the rear claw holding surface 510 and the front claw holding surface 511 are chamfered. The inner diameter portion of the front claw holding surface 511 is a curved surface, and the inner diameter edge 440E, which is the connection point between the claw support surface 441 and the pressing surface 440 of the cap member 4, is located on this front side.

[0056] In this embodiment, the lock ring 5 is provided with a plurality of claws 50 formed by bending in the axial direction of the joint body 3 on the inner surface of the claw holding portion 51. Each claw 50 is arranged on the inner circumferential surface of the claw holding portion 51 at equal intervals in the circumferential direction. Furthermore, each claw 50 is formed to be inclined toward the back as it moves inward in the annular shape of the lock ring 5. In other words, the claws 50 are bent so as to be inclined toward the insertion direction of the pipe body 2, i.e., toward the back. The outer diameter line of the claws 50 is formed in an arc shape. The virtual circle connecting the tips 500 of the claws 50 has a diameter slightly smaller than the outer diameter of the pipe body 2. That is, the tips 500 of the claws 50 are located diametrically inward from the extended surface 352 of the joint body 3 and the guide surface 434 of the cap member 4.

[0057] The outer surface 501 of the claw 50, located on the outer diameter side, is, for example, a flat surface. The inner surface 502 of the claw 50, located on the inner diameter side, is, for example, a flat surface.

[0058] The pair of locking rings 5 ​​described above are housed in the space surrounded by the locking surface 341 of the joint body 3, the pressing surface 440 of the cap member 4, and the inner surface of the joint body 3, that is, for example, the opposing surface 342 on the body side, and are configured such that the claws 50 engage with the outer surface of the inserted pipe 2 to restrict the removal of the pipe 2.

[0059] In this pair of lock rings 5, when an outward pulling force is applied to the pipe body 2, deformation of the claw 50 is suppressed when the inner surface 502 of the claw 50 of the front lock ring 5D, in this embodiment, the outer diameter portion of this inner surface 502, comes into contact with the claw support surface 441 of the cap member 4. In addition, the front side surface 511 of the claw holding portion 51 of the front lock ring 5D comes into contact with the pressing surface 440 of the cap member 4, restricting movement toward the front. Furthermore, even if the claw 50 of the front lock ring 5D deforms toward the front, the deformed claw 50 can be supported when the inner surface 502 of the claw 50 of the front lock ring 5D, in this embodiment, the outer diameter portion of this inner surface 502, comes into contact with the claw receiving surface 442 of the cap member 4.

[0060] Furthermore, the distance D1 between the claw support surface 441 of the cap member 4 and the inner surface 502 of the claw 50 of the front lock ring 5D is smaller than the distance D2 between the pressing surface 440 of the cap member 4 and the front claw holding surface 511 of the front lock ring 5D.

[0061] The claw contact ring 6 is housed within the annular space 53 of the lock ring 5. Furthermore, the claw contact ring 6 is housed within the annular space 53 in a manner that allows for radial displacement. In this embodiment, the claw contact ring 6 is made of metal. Additionally, the claw contact ring 6 is housed only within the annular space 53 of the front lock ring 5D, and not within the annular space 53 of the rear lock ring 5C.

[0062] Furthermore, the claw contact ring 6 is positioned in front of the claw 50 of the rear lock ring 5C, and has a claw contact surface 60 that contacts the claw 50 from the front when the claw 50 of the rear lock ring 5C deforms toward the front. The claw contact ring 6 of this embodiment has a claw holding contact surface 61 located on the outer diameter of the claw contact surface 60, in front of the claw holding portion 51 of the rear lock ring 5C. The claw contact ring 6 also has a deformation support surface 62 that contacts the claw holding portion 51 of the front lock ring 5D from the rear.

[0063] The claw contact ring 6 of this embodiment has a ring bottom surface 63 which is located on the inner diameter side of the claw contact ring 6, and a ring top surface 64 which is located on the outer diameter side of the claw contact ring 6. Furthermore, the claw contact ring 6 has a connecting surface 65 which connects the inner diameter edge of the deformation support surface 62 and the front edge of the ring bottom surface 63. The claw contact ring 6 has a rear connecting surface 66 which connects the inner diameter edge 60E of the claw contact surface 60 and the rear edge of the ring bottom surface 63.

[0064] The claw contact surface 60 is, for example, the surface that contacts the portion of the claw 50 of the inner lock ring 5C, excluding the tip portion 500. Specifically, the claw contact surface 60 faces the outer diameter portion of the claw 50 of the inner lock ring 5C, for example, a portion less than half of the outer diameter of the claw 50. Furthermore, the claw contact surface 60 is spaced apart from the outer diameter portion of the claw 50 of the inner lock ring 5C.

[0065] Furthermore, the claw contact surface 60 is a surface located on the inner and inner side of the diameter of the claw contact ring 6. In this embodiment, the claw contact surface 60 is positioned between the claw 50 of the inner lock ring 5C and the claw 50 of the outer lock ring 5D. That is, from the inner side to the outer side of the joint body 3, the claw 50 of the inner lock ring 5C, the claw contact surface 60, and the claw 50 of the outer lock ring 5D are arranged in this order.

[0066] Furthermore, the claw contact surface 60 extends in the direction in which the claw 50 of the inner lock ring 5C extends. For example, the claw contact surface 60 extends in a different direction from the claw holding contact surface 61. In this embodiment, the claw contact surface 60 is continuous with the claw holding contact surface 61 in the radial direction.

[0067] The claw contact surface 60 has an inner diameter edge 60E. The inner diameter edge 60E is positioned at a predetermined distance outward from the inner diameter tip edge of the inner surface 502 of the claw, which is the front side surface of the claw 50 of the rear lock ring 5C. Furthermore, the claw contact surface 60 is a surface parallel to the claw support surface 441 of the cap member 4. In addition, the claw contact surface 60 may be a flat surface or a curved surface, but for example, it is a flat surface.

[0068] With respect to the claw contact ring 6, the claw 50 of the rear lock ring 5C extends inward in diameter beyond the claw contact surface 60. Similarly, the claw 50 of the front lock ring 5D in this embodiment also extends inward in diameter beyond the claw contact surface 60.

[0069] The claw-holding contact surface 61 is, for example, the surface that contacts the claw-holding portion 51 of the rear lock ring 5C. Specifically, the claw-holding contact surface 61 contacts the front claw-holding side surface 511 of the rear lock ring 5C. Furthermore, the claw-holding contact surface 61 is located on the outer diameter side and on the rear side of the claw contact ring 6. The claw-holding contact surface 61 extends further outward from the outer diameter edge of the claw contact surface 60.

[0070] In this embodiment, the claw-holding contact surface 61 is positioned between the claw-holding portion 51 of the rear lock ring 5C and the claw-holding portion 51 of the front lock ring 5D. That is, from the rear to the front of the joint body 3, the claw-holding portion 51 of the rear lock ring 5C, the claw-holding contact surface 61, and the claw-holding portion 51 of the front lock ring 5D are arranged in this order.

[0071] Furthermore, the claw-holding contact surface 61 may be flat or curved, but for example, it is flat. In addition, the claw-holding contact surface 61 is a surface perpendicular to the axial direction of the joint body 3. The outer diameter portion of the claw-holding contact surface 61 is chamfered.

[0072] The deformation support surface 62 abuts against the rear side surface 510 of the claw-holding front lock ring 5D. The deformation support surface 62 is also located on the outer diameter side and front side of the claw-contacting ring 6. In this embodiment, the deformation support surface 62 is positioned between the claw-holding portion 51 of the rear lock ring 5C and the claw-holding portion 51 of the front lock ring 5D. That is, from the rear side to the front side of the joint body 3, the claw-holding portion 51 of the rear lock ring 5C, the deformation support surface 62, and the claw-holding portion 51 of the front lock ring 5D are arranged in this order.

[0073] Furthermore, the deformation support surface 62 may be a flat or curved surface, but for example, it is flat. In addition, the deformation support surface 62 is a surface perpendicular to the axial direction of the joint body 3. Since the deformation support surface 62 is a surface parallel to the claw holding contact surface 61, the lock ring 5 and the claw contact ring 6 come into contact, allowing the lock ring 5 to perform its intended function. Also, the deformation support surface 62 is positioned spaced apart from the claw holding contact surface 61, towards the rear.

[0074] The outer diameter portion of the deformation support surface 62 is chamfered. In the axial direction of the joint body 3, the distance between the deformation support surface 62 and the claw holding contact surface 61 should be such that the claw contact ring 6 is sandwiched between the pair of lock rings 5 ​​in a manner that allows for radial displacement of the claw contact ring 6.

[0075] The bottom surface 63 of the ring extends from the inner diameter edge 66E of the rear connecting surface 66 toward the front. Specifically, the bottom surface 63 extends in the axial direction of the joint body 3. Furthermore, the bottom surface 63 is located radially outward from the tip 500 of the claw 50 of the lock ring 5.

[0076] Furthermore, the ring bottom surface 63 is, for example, an annular surface. The ring bottom surface 63 may be a flat or curved surface, but for example, it is a flat surface. Moreover, the ring bottom surface 63 is a surface that extends in the axial direction of the joint body 3. Furthermore, the distance between the ring bottom surface 63 of the claw contact ring 6 and the axis α of the joint body 3 is equal to the distance between the extended surface 352 of the joint body 3 and the axis α of the joint body 3.

[0077] The top surface 64 of the ring extends between the outer edge of the claw-holding contact surface 61 and the outer edge of the deformation support surface 62. The top surface 64 of the ring may be flat or curved, but for example, it is flat. The top surface 64 of the ring extends parallel to the inner surface 522 of the flange of the front lock ring 5D. The rear and front portions of the top surface 64 of the ring in this embodiment are chamfered.

[0078] Furthermore, the top surface of the ring 64 extends parallel to, for example, the inner surface 522 of the flange of the front locking ring 5D. Also, the top surface of the ring 64 is positioned radially inward from the inner surface 522 of the flange of the front locking ring 5D. In this embodiment, the radial distance between the top surface of the ring 64 and the inner surface 522 of the flange is equal at all parts of the joint body 3 in the axial direction, except for the chamfered portion of the top surface of the ring 64.

[0079] The connecting surface 65 is positioned in front of the claw contact surface 60. The connecting surface 65 may be a flat or curved surface, but for example, it is flat. Furthermore, the connecting surface 65 is positioned between the inner diameter portion and claw 50 of the claw holding portion 51 of the rear lock ring 5C and the inner diameter portion and claw 50 of the claw holding portion 51 of the front lock ring 5D. The connecting surface 65 is positioned spaced inward in relation to the outer claw surface 501 of the front lock ring 5D. The distance D3 between the connecting surface 65 and the outer claw surface 501 of the lock ring 5D is greater than the distance D1 between the claw support surface 441 of the cap member 4 and the inner surface 502 of the claw 50 of the front lock ring 5D.

[0080] The rear connecting surface 66 is positioned further back than the claw contact surface 60. The rear connecting surface 66 may be a flat or curved surface, but for example, it is flat. The rear connecting surface 66 is a surface perpendicular to the axial direction of the joint body 3. Furthermore, the rear connecting surface 66 extends radially inward from the radially inward end edge 60E of the claw contact surface 60.

[0081] Furthermore, the rear connecting surface 66 is positioned between the claw 50 of the rear locking ring 5C and the claw 50 of the front locking ring 5D. The rear connecting surface 66 is positioned spaced apart from the inner surface 502 of the claw 5C towards the front. In this embodiment, the inner diameter edge 66E of the rear connecting surface 66 is located radially outward from the inner tip edge 50E of the claw 50 of the rear locking ring 5C and the front locking ring 5D.

[0082] Furthermore, in this embodiment, the claw contact ring 6 is positioned such that the distance between the inner diameter edge 66E of the rear connection surface 66 and the axis α of the joint body 3 matches the distance between the inner diameter edge 341E of the locking surface 341 of the joint body 3 and the axis α of the joint body 3. Also, the distance between the inner diameter edge 66E of the rear connection surface 66 and the axis α of the joint body 3 is greater than the distance between the inner diameter edge 442E of the claw receiving surface 442 of the cap member 4 and the axis α of the joint body 3.

[0083] In the pipe joint 1 described above, the cap member 4 is provided with a claw support surface 441 that contacts the claw 50 of the lock ring 5 from the front side. Therefore, even if a pulling force acts on the pipe body 2 and a force is applied to the front side lock ring 5D causing the claw 50 of the front side lock ring 5D to deform, it will still contact the claw support surface 441, thus suppressing deformation of the claw 50. As a result, the locking of the claw 50 to the outer surface of the pipe body 2 can be maintained, and the pulling out of the pipe body 2 is sufficiently restricted.

[0084] In the pipe fitting 1 of this embodiment, the pressing surface 440 of the cap member 4 abuts against the claw holding portion 51 of the front lock ring 5D from the front side. Therefore, even if a force is applied to the front lock ring 5D toward the front, the claw holding portion 51, or in this embodiment, the front side surface 511 of the claw holding portion 51, abuts against the pressing surface 440, thus supporting the claw holding portion 51 so that it does not shift toward the front side.

[0085] Furthermore, in the pipe fitting 1 of this embodiment, the claw receiving surface 442 of the cap member 4 extends inward from the inward diameter end edge 441E of the claw support surface 441. Therefore, even if a force is applied to the front lock ring 5D toward the front and the claw 50 deforms toward the front, the deformed claw 50 can be supported by the claw receiving surface 442.

[0086] Furthermore, in the pipe joint 1 of this embodiment, since the claw contact surface 60 is provided on the claw contact ring 6, even if a pulling force acts on the pipe body 2 and a force is applied to the claw 50 of the rear lock ring 5C toward the front, causing the claw 50 to deform toward the front, the claw 50 will still contact the claw contact surface 60. At this time, the claw contact ring 6 is allowed to move radially within the annular space 53. Specifically, the rear lock ring 5C and the front lock ring 5D are surrounded by the flange 52 in the radial direction, and the front lock ring 5D's movement toward the front is restricted by contact with the retaining surface 440. Since the claw contact ring 6 is allowed to move radially within the rear lock ring 5C and the front lock ring 5D, the claw contact ring 6 is centered by contact with the claw 50 of the rear lock ring 5C, resulting in a configuration where the axis of the claw contact ring 6 coincides with the axis of the pipe body 2. Therefore, each of the claws 50 provided on the rear lock ring 5C makes even contact with the claw contact surface 60.

[0087] As the tube 2 is further withdrawn, the claw 50 of the inner lock ring 5C, while aligned with the claw contact surface 60 of the claw contact ring 6, bites into the tube 2 with the portion of the claw 50 located inward from the claw contact surface 60, thereby sufficiently restricting the withdrawal of the tube 2.

[0088] Furthermore, in the pipe joint 1 of this embodiment, the claw-holding contact surface 61 is located on the outer diameter of the claw-holding contact surface 60 and on the front side of the claw-holding portion 51 of the inner lock ring 5C. Therefore, when an outward pulling force is applied to the pipe body 2, the claw-holding contact surface 61 contacts the claw-holding portion 51 of the inner lock ring 5C from the front side, thereby reliably restricting the deformation of the claw-holding portion 51.

[0089] Furthermore, in the pipe joint 1 of this embodiment, since the deformation support surface 62 contacts the claw holding portion 51 of the front lock ring 5D from the rear side, even if an outward pulling force is generated in the pipe body 2, causing the claw 50 of the rear lock ring 5C to deform and pressure to be applied to the claw contact surface 60 and the claw holding contact surface 61, the deformation support surface 62 in the claw contact ring 6 can support the claw contact surface 60 and the claw holding contact surface 61 so that they do not shift towards the rear.

[0090] In the pipe fitting 1 of this embodiment, the claw contact ring 6 is positioned such that the distance between the ring bottom surface 63 of the claw contact ring 6 and the axis α of the fitting body 3 is the same as the distance between the diameter inner edge 341E of the locking surface 341 of the fitting body 3 and the axis α of the fitting body 3. As a result, the ring bottom surface 63 of the claw contact ring 6 is positioned as far away from the axis α of the fitting body 3 as the diameter inner edge 341E of the locking surface 341 of the fitting body 3. Therefore, when inserting the pipe body 2 into the fitting body 3, the claw contact ring 6 is prevented from interfering with the pipe body 2. Furthermore, when a pulling force is applied to the pipe body 2, the claws 50 of the rear locking ring 5C can contact the claw contact surface 60 to the greatest extent possible, allowing the claws 50 to bite into the pipe body 2.

[0091] Furthermore, in the pipe joint 1 of this embodiment, the claw contact ring 6 is provided with a claw contact surface 60 that extends in the direction in which the claws 50 of the lock ring 5 extend. As a result, even if a pulling force is applied to the pipe body 2 and the claws 50 of the inner lock ring 5C deform toward the front, the claws 50 will still come into contact with the claw contact surface 60. At this time, the deformation of the claws 50 of the inner lock ring 5C is restricted by the claw contact surface 60. Therefore, the portion of the claws 50 located inward in diameter from the claw contact surface 60, for example, the tip portion 500, firmly bites into the pipe body 2, thereby sufficiently restricting the pulling out of the pipe body 2.

[0092] Furthermore, in the pipe joint 1 of this embodiment, since the bottom surface 63 of the ring is flat, even if the bottom surface 63 comes into contact with the pipe body 2, the pipe body 2 will not be damaged by the bottom surface 63 of the ring. In addition, because the bottom surface 63 of the ring is flat, the strength of the part of the claw contact ring 6 on the side of the bottom surface 63 is ensured, so even if a pulling force is applied to the pipe body 2 and the claw 50 of the inner lock ring 5C deforms, the bottom surface 63 of the ring can support the claw contact surface 60 so that it does not shift inward.

[0093] Although one embodiment of the present invention has been described, the present invention is not limited to the above-described embodiment.

[0094] For example, the cap member 4 in the above embodiment had a claw receiving surface 442, but it does not have to have a claw receiving surface 442. Also, the lock ring 5 in the above embodiment had a flange portion 52, but it is sufficient to have at least a claw 50, and may be composed of, for example, a claw 50 and a claw holding portion 51. The claw contact ring 6 in the above embodiment had an inner connecting surface 66, but it does not have to have an inner connecting surface 66. A specific example of such a configuration will be explained below with reference to Figure 3.

[0095] The rear end face 44 of the small diameter portion 43 of the cap member 4 includes a pressing surface 440 positioned on the front side of the claw holding portion 51 of the lock ring 5, and a claw support surface 441 that contacts the claw 50 from the front side when the claw 50 deforms toward the front. In the radial direction, the inner diameter edge 441E of the claw support surface 441 is positioned at the same location as the inner diameter edge 341E of the locking surface 341 of the joint body 3. The rear end face 44 of the small diameter portion also has a second contact surface 443 on the cap side. An annular recess 444 is formed between the pressing surface 440 and the second contact surface 443 on the rear end face 44 of the small diameter portion.

[0096] Furthermore, the small-diameter portion 43 of the cap has a guide surface 434 that extends towards the front from the inner diameter edge 441E of the claw support surface 441. In this configuration, the inner diameter edge 441E of the claw support surface 441, which is the boundary between the claw support surface 441 and the guide surface 434, becomes a fulcrum where the inner diameter portion of the claw 50 bends relative to its base. In this embodiment, when the pipe body 2 is pulled out in the tensile direction, the deformed claw 50 is prevented from deforming further once it is facing radially from the fulcrum, causing it to bite into the pipe body 2. As a result, the tensile force is increased at the inner diameter edge 441E of the claw support surface 441, which is the boundary between the guide surface 434 and the claw support surface 441.

[0097] The lock ring 5 has a claw 50 that engages with the outer surface of the pipe 2 inserted into the joint body 3 to restrict the removal of the pipe, and a claw holding portion 51 that extends outward from the diameter of the claw 50.

[0098] The claw-holding portion 51 in this embodiment is an annular portion extending in a direction perpendicular to the axial direction of the joint body 3. The portion on the inner side of the front claw-holding surface 511 is a curved surface and is located on the outer side of the inner edge 440E, which is the connection point between the claw support surface 441 and the pressing surface 440 of the cap member 4.

[0099] In this pair of locking rings 5, when an outward pulling force is applied to the pipe body 2, the inner surface 502 of the claw 50 of the front locking ring 5D comes into contact with the claw support surface 441 of the cap member 4, thereby suppressing deformation of the claw 50. In addition, the front side surface 511 of the claw holding portion 51 of the front locking ring 5D comes into contact with the pressing surface 440 of the cap member 4, thereby restricting movement toward the front.

[0100] The distance D1 between the claw support surface 441 of the cap member 4 and the inner surface 502 of the claw 50 of the front lock ring 5D increases towards the outer diameter. Also, the distance D1 between the claw support surface 441 of the cap member 4 and the outer surface 501 of the claw 50 of the front lock ring 5D is greater than the distance D2 between the pressing surface 440 of the cap member 4 and the front claw holding surface 511 of the front lock ring 5D.

[0101] The claw contact ring 6 has a claw contact surface 60, a claw holding contact surface 61, a deformation support surface 62, a ring bottom surface 63, a ring top surface 64, and a connecting surface 65. Furthermore, the claw contact ring 6 is housed only inside the front lock ring 5D and not inside the rear lock ring 5C.

[0102] The claw contact surface 60 is, for example, the surface that contacts the entire area of ​​the claw 50 of the inner lock ring 5C, excluding the tip portion 500. The claw contact surface 60 also has an inner diameter edge 60E. The inner diameter portion of the claw contact surface 60 is chamfered.

[0103] The top surface of the ring 64 extends parallel to the inner surface of the joint body 3, for example, the opposing surface 342 on the body side. The top surface of the ring 64 is also positioned at a distance from the opposing surface 342 on the body side inward. In this embodiment, the rear and front portions of the top surface of the ring 64 are chamfered, and the radial distance between the top surface of the ring 64 and the opposing surface 342 on the body side is equal at all parts of the joint body 3 in the axial direction, except for the chamfered portions of the top surface of the ring 64.

[0104] The distance D3 between the connecting surface 65 and the outer surface 501 of the claw of the lock ring 5D is smaller than the distance D1 between the claw support surface 441 of the cap member 4 and the inner surface 502 of the claw 50 of the front lock ring 5D.

[0105] Furthermore, in this embodiment, the claw contact ring 6 is positioned such that the distance between the inner diameter edge 60E of the claw contact surface 60 and the axis α of the joint body 3 matches the distance between the inner diameter edge 341E of the locking surface 341 of the joint body 3 and the axis α of the joint body 3. Also, the distance between the inner diameter edge 60E of the claw contact surface 60 and the axis α of the joint body 3 matches the distance between the inner diameter edge 441E of the claw support surface 441 of the cap member 4 and the axis α of the joint body 3.

[0106] In the above embodiment, all the seal rings 8 were positioned in front of the pair of lock rings 5. However, as shown in Figure 4, some of the seal rings 8 may be positioned in front of the pair of lock rings 5, while the remaining seal rings 8 are positioned behind the pair of lock rings 5.

[0107] As shown in Figure 5, the large-diameter portion 32 of the joint body 3 has a second contact surface 322 on the body side that contacts the cap member 4. The second contact surface 322 on the body side is, for example, a surface perpendicular to the axial direction of the joint body 3.

[0108] The rear end face 44 of the small diameter portion 43 of the cap is provided with a pressing surface 440 and a claw support surface 441. The rear end face 44 of the small diameter portion also has a second contact surface 443 on the cap side. This second contact surface 443 on the cap side contacts the locking surface 341 of the joint body 3. The small diameter portion 43 of the cap has a guide surface 434 that extends towards the front from the inner diameter end edge 441E of the claw support surface 441.

[0109] The seal ring 8 includes a large-diameter seal ring 80, an auxiliary seal ring 81, and a small-diameter seal ring 82 (see Figure 4). The large-diameter seal ring 80 and the pair of auxiliary seal rings 81 are positioned on the front side of the pair of lock rings 5. The small-diameter seal ring 82 is positioned on the back side of the pair of lock rings 5.

[0110] The outer diameter portion of the large-diameter seal ring 80 is housed in a housing portion 320 formed on the inner surface of the front side of the large-diameter portion 32 of the main body of the joint body 3. The inner diameter portion of the large-diameter seal ring 80 is housed in a cap-side large-diameter seal housing portion 420 formed on the front side of the outer surface of the small-diameter portion 43 of the cap. The auxiliary seal ring 81 is housed in an auxiliary seal housing portion 410 formed on the inner surface of the reduced-size portion 41 of the cap member 4.

[0111] An annular one-small-diameter seal housing portion 323 is formed on the inner surface of the large-diameter portion 32 of the joint body 3 for housing one of the small-diameter seal rings 82. An annular other-small-diameter seal housing portion 343 is formed on the inner surface of the first small-diameter portion 34 of the joint body 3 for housing the other small-diameter seal ring 82. The small-diameter seal housing portions 323 and 343 are spaced apart in the axial direction of the joint body 3.

[0112] The lock ring 5 has a claw 50 that engages with the outer surface of the pipe 2 inserted into the joint body 3 to restrict the removal of the pipe 2, a claw holding portion 51 that extends outward from the diameter of the claw 50, and a flange portion 52 (see Figure 5). The configuration of this lock ring 5 is the same as that shown in Figure 2.

[0113] The claw contact ring 6 has a claw contact surface 60, a claw holding contact surface 61, a deformation support surface 62, a ring bottom surface 63, a ring top surface 64, and a connecting surface 65 (see Figure 5). The configuration of this claw contact ring 6 is the same as that shown in Figure 3.

[0114] As shown in Figure 6, in a configuration where some of the seal rings 8 are positioned in front of the pair of lock rings 5 ​​and the remaining seal rings 8 are positioned behind the pair of lock rings 5, the lock rings 5 ​​do not necessarily have a flange portion 52.

[0115] The small-diameter portion 43 of the cap member 4 has an inner surface 436 of the small-diameter portion that extends inward from the outer diameter edge of the pressing surface 440 of the rear end face 44 of the small-diameter portion. The inner surface 436 of the small-diameter portion is, for example, a plane that extends in the axial direction.

[0116] The top surface of the ring 64 extends parallel to the inner surface of the cap member 4, for example, the inner surface of the small diameter portion 436. The top surface of the ring 64 is also positioned at a distance inward from the inner surface of the small diameter portion 436. In this embodiment, the rear and front portions of the top surface of the ring 64 are chamfered, and the radial distance between the top surface of the ring 64 and the inner surface of the small diameter portion 436 is equal at all parts of the joint body 3 in the axial direction, except for the chamfered portions of the top surface of the ring 64.

[0117] The cap member 4 in the above embodiment had a reduced portion 41 which is the front end, a large-diameter cap portion 42 integrally formed on the rear side of the reduced portion 41, and a small-diameter cap portion 43 integrally formed on the rear side of the large-diameter cap portion 42, but the shape of the cap member 4 is not limited. For example, the cap member 4 may have a shape with a uniform outer diameter, and even with this configuration, it is sufficient that the rear end face of the cap member 4 is provided with at least a claw support surface 441. Furthermore, it is sufficient that the rear end face of the cap member 4 is provided with a claw receiving surface 442 and a pressing surface 440.

[0118] The claw contact ring 6 in the above embodiment had a claw contact surface 60, a claw holding contact surface 61, a deformation support surface 62, etc., but it is sufficient to have at least a claw contact surface 60. For example, the claw contact ring 6 may not have a claw holding contact surface 61. Also, the claw contact ring 6 may not have a deformation support surface 62.

[0119] In the above embodiment, the claw contact surface 60 was a surface inclined with respect to the axial direction of the joint body 3, but it may also be a surface perpendicular to this axial direction.

[0120] In the above embodiment, the bottom surface 63 of the claw contact ring 6 was flat, but it may be a curved surface. For example, this bottom surface 63 may be a curved surface that is convex toward the inner diameter.

[0121] In the above embodiment, the multiple claws 50 of the lock ring 5 were arranged at equal intervals in the circumferential direction, but they may be arranged at different intervals in the circumferential direction.

[0122] In the above embodiment, the cap member 4 was assembled to the joint body 3 by screw fastening, but it may also be assembled by other methods such as fitting. [Explanation of symbols]

[0123] 1...Pipe fitting, 2A, 2B, 2...Pipe body, 3...Fitting body, 4...Cap member, 5...Lock ring, 5C...Inner lock ring, 5D...Front lock ring, 6...Claw contact ring, 7...Pipe fitting section, 8...Seal ring, 20...Innermost end face, 30...Opening, 31...Insertion space on the main body side, 32...Large diameter section of the main body, 33...Small diameter section of the main body, 34...First small diameter section of the main body, 35...Second small diameter section of the main body, 40...Insertion space on the cap side, 41...Reduced section, 42...Large diameter section of the cap, 43...Small diameter section of the cap, 44...Inner end face of the small diameter section ,50...claw, 50E...inner tip edge, 51...claw holding part, 52...flange part, 52...flange, 53...annular space, 60E...inner diameter edge, 61...claw holding contact surface, 62...deformation support surface, 63...ring bottom surface, 64...ring top surface, 65...connecting surface, 66...inner side connecting surface, 66E...inner diameter edge, 80...large diameter seal ring, 81...auxiliary seal ring, 82...small diameter seal ring, 101...pipe fitting, 103...fitting body, 104...cap member, 105...lock ring, 150...flange, 151... Claw holding part, 152...claw, 310...lock ring housing part, 320...large diameter seal housing part on the main body side, 320...housing part, 321...first contact surface on the main body side, 322...second contact surface on the main body side, 323...small diameter seal housing part on one side, 340...second contact surface on the main body side, 341...locking surface, 341E...inner edge of diameter, 342...opposing surface on the main body side, 343...other small diameter seal housing part, 350...stepped surface, 351...stepped wall, 352...extended surface, 410...auxiliary seal housing part, 420...large diameter seal housing part on the cap side, 421...cap 434...First contact surface on the cap side, 435...Guide surface, 436...Small diameter seal housing part on the cap side, 440...Inner surface of the small diameter part, 440...Pressing surface, 440E...Inner edge of the diameter, 441...Claw support surface, 441E...Inner edge of the diameter, 442...Claw receiving surface, 442E...Inner edge of the diameter, 443...Second contact surface on the cap side, 444...Recess, 500...Tip part, 501...Outer surface of the claw, 502...Inner surface of the claw, 510...Inner side of the claw holding, 511...Front side of the claw holding, 521...Outer surface of the flange, 522...Inner surface of the flange, D1, D2, D3...Distance, α...Axis

Claims

1. A pipe joint for connecting pipes, A cylindrical joint body is provided with an opening into which the pipe is inserted, and the pipe is inserted into the inner side through the opening, A cylindrical cap member assembled to the aforementioned opening, The joint body comprises a locking ring formed in an annular shape centered on the axial direction of the joint body, having claws that engage with the outer surface of the pipe inserted into the joint body to restrict the removal of the pipe, The aforementioned claws are formed to be inclined so that the diameter on the inner side of the annular shape is inclined toward the inner side. The cap member is positioned on the front side of the claw and has a claw support surface that contacts the claw from the front side when the claw deforms toward the front side. The claw support surface is formed to be inclined so that the inner diameter is inward. Pipe fittings.

2. The locking ring includes a claw-holding portion that extends outward from the diameter of the claw, The cap member has a pressing surface positioned on the front side of the claw holding portion, The claw support surface is formed with an inclination that extends inward from the inner diameter edge of the pressing surface as the inner diameter increases. The pipe fitting according to claim 1.

3. The cap member comprises a claw receiving surface extending inward from the inner diameter edge of the claw support surface. A pipe fitting according to claim 1 or claim 2.

Images