Joint structure

Abstract

The present invention provides a joint structure that allows for easier attachment of a sealing member to the inner circumferential surface of the socket of the pipe to be joined. [Solution] The joint structure 1 has an insertion port 3 of pipe W2, a receiving port 2 of the pipe to be joined W1 to be joined to pipe W2, and an annular sealing member 20 that seals the space between the outer circumferential surface 3a of the insertion port 3 of pipe W2 and the inner circumferential surface 2a of the receiving port 2 of the pipe to be joined W1. The joint structure 1 has an annular mounting member 30 for attaching the sealing member 20 to the inner circumferential surface 2a of the receiving port 2 of the pipe to be joined W1. The receiving port 2 of the pipe to be joined W1 has a receiving port groove 15 extending in the circumferential direction on its inner circumferential surface 2a. A part 21 of the sealing member is inserted into the receiving port groove 15. The mounting member 30 is positioned to contact the part 21 of the sealing member and the respective inner circumferential surfaces 21a, 2a of the pipe to be joined W1, and to press the part 21 of the sealing member radially outward against the bottom surface 15a of the receiving port groove 15.

Description

Technical Field

[0001] The present invention relates to a joint structure having a tube insertion port, a receiving port of a joined tube joined to the tube, and an annular sealing member that seals between an outer peripheral surface of the tube insertion port and an inner peripheral surface of the receiving port of the joined tube.

Background Art

[0002] A tube joint structure having a sealing member between an outer peripheral surface of a tube insertion port and an inner peripheral surface of a receiving port of a joined tube is known. For example, in Patent Document 1, an insertion port formed at an end of one tube is inserted into a receiving port formed at an end of the other tube, and an annular sealing material is disposed in a sealing material accommodation groove formed on the inner periphery of the receiving port, and the sealing material is compressed between the receiving port and the insertion port to seal between the receiving port and the insertion port. A detachment prevention tube joint is disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the tube joint as in Patent Document 1, an annular sealing member that seals between an outer peripheral surface of a tube insertion port and an inner peripheral surface of a receiving port of a joined tube is attached in a concave groove formed to extend in the circumferential direction on the inner peripheral surface of the joined tube. Therefore, it is necessary to pass the opening of the receiving port of the joined tube in the axial direction while deforming the annular sealing member radially inward to attach the sealing member in the groove. Therefore, a joint structure that can more easily attach the sealing member on the inner peripheral surface of the receiving port of the joined tube is desired.

[0005] The object of the present invention is to provide a joint structure that allows for easier attachment of a sealing member to the inner circumferential surface of the socket of the pipe to be joined. [Means for solving the problem]

[0006] A joint structure according to one embodiment of the present invention comprises a pipe spigot, a receiving end of a pipe to be joined to the pipe, and an annular sealing member that seals the space between the outer circumferential surface of the pipe spigot and the inner circumferential surface of the receiving end of the pipe to be joined. The joint structure has a mounting member that extends circumferentially to fix the sealing member on the inner circumferential surface of the receiving end of the pipe to be joined. The receiving end of the pipe to be joined has a receiving end groove that extends circumferentially on its inner circumferential surface. A portion of the sealing member is inserted into the receiving end groove. The mounting member is positioned to contact a portion of the sealing member and the inner circumferential surface of the pipe to be joined, and to press a portion of the sealing member radially outward against the bottom surface of the receiving end groove (first configuration).

[0007] According to the above configuration, the sealing member can be fixed to the inner circumferential surface of the pipe to be joined by the mounting member such that a portion of the sealing member is pressed radially outward against the bottom surface of the receiving groove portion of the pipe to be joined.

[0008] As a result, even if the depth of the receiving groove is made shallower, for example, the mounting member can more securely attach the sealing member to the inner circumferential surface of the pipe to be joined. Therefore, since the depth of the receiving groove can be made shallower compared to the conventional configuration, there is no need to significantly deform the sealing member radially inward when attaching it to the receiving groove. Thus, the sealing member can be easily attached to the inner circumferential surface of the pipe to be joined.

[0009] Therefore, by using the mounting member, a joint structure can be realized in which the sealing member can be more easily attached to the inner circumferential surface of the receiving end of the pipe to be joined.

[0010] In the first configuration described above, the mounting member is positioned to overlap the receiving groove when viewed radially across the pipe to be joined, and has a pressing portion that contacts the inner circumferential surface of a portion of the sealing member such that at least a part of it presses a portion of the sealing member radially outward against the bottom surface of the receiving groove, and a receiving contact portion that extends axially across the pipe to be joined from the pressing portion so as to contact the inner circumferential surface of the pipe to be joined that is on the receiving opening side of the receiving groove (second configuration).

[0011] According to the above configuration, after inserting a portion of the sealing member into the receiving groove of the pipe to be joined, the sealing member can be fixed to the receiving groove by the receiving contact portion of the mounting member while the pressing portion of the mounting member presses the portion of the sealing member radially outward relative to the bottom surface of the receiving groove.

[0012] As a result, the sealing member can be attached to the inner circumferential surface of the pipe to be joined by the retaining portion and the receiving contact portion of the mounting member.

[0013] Therefore, a joint structure can be realized that allows for easier attachment of the sealing member and the mounting member to the pipe to be joined.

[0014] In the second configuration described above, the sealing member has a portion inserted into the receiving groove portion as part of the sealing member, and an annular sealing portion extending radially inward from the portion inserted into the receiving groove portion and in contact with the outer circumferential surface of the insertion opening of the pipe and the inner circumferential surface of the receiving opening of the pipe to be joined. At least a portion of the retaining portion is positioned in the axial direction relative to the sealing portion and is in contact with the inner circumferential surface of the portion inserted into the receiving groove portion (third configuration).

[0015] According to the above configuration, the retaining portion is positioned axially with respect to the sealing portion and can press the insertion portion into the receiving groove radially outward relative to the receiving groove. As a result, even if a force is applied to the sealing portion that presses it toward the receiving opening due to, for example, water pressure inside the pipe to be joined, the retaining portion presses the insertion portion into the receiving groove radially outward relative to the receiving groove while contacting the sealing portion, thereby preventing the sealing member from moving axially toward the receiving opening.

[0016] In the third configuration described above, the mounting member further has a protruding portion that extends from the pressing portion toward the receiving groove portion (fourth configuration).

[0017] According to the above configuration, the protruding portion is located within the receiving groove. As a result, even if an axial force is applied to the sealing member by, for example, water pressure inside the pipe to be joined, the sealing member and the mounting member are less likely to move in the axial direction, thus allowing the sealing member to be held more securely within the receiving groove.

[0018] In the fourth configuration described above, the insertion portion within the receiving groove has a notch in which a part of the inner circumferential surface is cut out. At least a part of the protruding portion protrudes from the retaining portion toward the notch and is located within the receiving groove and within the notch (fifth configuration).

[0019] This allows the portion of the sealing member inserted into the receiving groove to be sandwiched between the protruding portion of the mounting member and the bottom surface of the receiving groove. Thus, the sealing member can be securely fixed to the inner circumferential surface of the receiving end of the pipe to be joined.

[0020] In the second configuration described above, the socket contact portion extends in the axial direction from the pressing portion to the socket opening end of the pipe to be joined (sixth configuration).

[0021] As a result, the contact area of the socket contact portion with respect to the inner peripheral surface of the joined pipe increases. Therefore, the mounting member can more stably hold the sealing member with respect to the inner peripheral surface of the joined pipe. Thus, a joint structure can be provided in which the sealing member is difficult to come off from the inner peripheral surface of the joined pipe.

[0022] In the sixth configuration, the inner peripheral surface of the socket contact portion includes an inclined surface whose inner diameter decreases in the insertion direction of the pipe from the end portion on the socket opening side (seventh configuration).

[0023] According to the above configuration, by inserting the insertion port of the pipe into the joined pipe while bringing the insertion port of the pipe into contact with the inclined surface of the socket contact portion, the insertion port of the pipe can be joined to the socket of the joined pipe while centering the insertion port of the pipe with respect to the socket of the joined pipe. Therefore, the mounting member can prevent the displacement of the sealing member, and a joint structure that can more easily join the insertion port of the pipe to the socket of the joined pipe can be provided.

Advantages of the Invention

[0024] The joint structure according to an embodiment of the present invention has an annular mounting member for attaching a sealing member on the inner peripheral surface of the socket of the joined pipe. The socket of the joined pipe has a socket groove portion extending in the circumferential direction on the inner peripheral surface. A part of the sealing member is inserted into the socket groove portion. The mounting member is arranged to contact a part of the sealing member and the inner peripheral surface of the joined pipe respectively, and to press a part of the sealing member radially outward with respect to the bottom surface of the socket groove portion.

[0025] As a result, the mounting member can more reliably attach the sealing member on the inner peripheral surface of the joined pipe. Thus, a joint structure that can more easily attach the sealing member on the inner peripheral surface of the socket of the joined pipe can be provided.

Brief Description of the Drawings

[0026] [Figure 1] FIG. 1 is an end view showing a schematic configuration of the joint structure. [Figure 2]Figure 2 is a partially enlarged view of the end face of the joint structure in Figure 1. [Figure 3] Figure 3 is a front view showing the schematic configuration of the mounting member. [Figure 4] Figure 4 is a flowchart showing the method of joining a pipe to a pipe to be joined. [Figure 5A] Figure 5A is a schematic cross-sectional view showing how a sealing member is placed within the socket groove of the socket of the pipe to be joined. [Figure 5B] Figure 5B is a schematic cross-sectional view showing how an attachment member is installed inside a pipe to be joined, where a sealing member is located. [Figure 5C] Figure 5C is a schematic cross-sectional view showing how the insertion end of a pipe is inserted into the socket of a pipe to be joined, which has a sealing member attached using an attachment member. [Figure 6] Figure 6 is an end view showing a schematic configuration of the joint structure according to the modified example. [Figure 7] Figure 7 is a partially enlarged view of the joint structure in Figure 6. [Modes for carrying out the invention]

[0027] The embodiments and modifications thereof will be described below with reference to the drawings. In each drawing, the same parts are denoted by the same reference numerals, and the description of those parts will not be repeated. Note that the dimensions of the components in each drawing do not faithfully represent the dimensions of the actual components or the dimensional ratios of each component.

[0028] In the following explanation, the direction in which the axis P of the pipe to be joined extends is referred to as the axial direction, the direction perpendicular to the axial direction is referred to as the radial direction, and the direction along the arc centered on axis P is referred to as the circumferential direction. In joint structure 1, the axis P of the pipe to be joined and the axis of pipe W2 coincide.

[0029] Furthermore, in the following explanation, the expressions "fix," "connect," and "attach" (hereinafter referred to as "fixing, etc.") include not only cases where components are directly fixed to each other, but also cases where they are fixed to each other via other components. In other words, in the following explanation, the expressions "fixing, etc." include both direct and indirect fixing of components to each other.

[0030] (Joint structure) Figure 1 is an end view showing the schematic configuration of the joint structure 1. Note that Figure 1 is an end view of the joint structure 1 when it is cut axially by a plane containing the axis P of the pipe to be joined W1. Figure 2 is a partially enlarged view of the end view of the joint structure 1 in Figure 1. Figure 3 is a front view showing the schematic configuration of the mounting member 30.

[0031] As shown in Figure 1, the joint structure 1 includes an insertion port 3 for pipe W2, a receiving port 2 for the pipe to be joined W1, a sealing member 20, and a mounting member 30. The sealing member 20 seals the space between the inner circumferential surface 2a of the receiving port 2 and the outer circumferential surface 3a of the insertion port 3.

[0032] Pipe W2 and the pipe to be joined W1 are, for example, water pipes. Pipe W2 and the pipe to be joined W1 may be pipes other than water pipes, such as sewer pipes, agricultural water pipes, or gas pipes. Pipe W2 and the pipe to be joined W1 may be ductile cast iron pipes, other metal pipes, or resin pipes.

[0033] Pipe W2 has a socket 3 at its other axial end. The pipe to be joined W1 has a socket 2 at one axial end into which the socket 3 of pipe W2 can be inserted. The socket end 12 located at one axial end of the socket 2 has an opening H.

[0034] The socket 2 of the pipe to be joined W1 has a lock ring groove 14 and a socket groove portion 15 on its inner circumferential surface 2a. The socket groove portion 15 is located on the opening side of the socket 2, relative to the lock ring groove 14.

[0035] The locking ring groove 14 is an annular groove extending around the entire circumference on the inner surface of the socket 2. A locking ring M is positioned within the locking ring groove 14. The locking ring M positioned within the locking ring groove 14 restricts the insertion end 3 of the pipe W2, which is inserted into the socket 2 of the pipe W1 to be joined, from coming out axially from the socket 2. The configuration of the locking ring groove 14 and the locking ring M is the same as that of a typical locking ring groove and locking ring. Therefore, a description of the locking ring groove 14 and the locking ring M is omitted.

[0036] The receiving groove 15 is an annular groove extending around the entire circumference on the inner circumferential surface 2a of the receiving opening 2. As shown in Figure 2, the receiving groove 15 has a substantially rectangular cross-section. The receiving groove 15 has a bottom surface 15a, one side surface 15b, and the other side surface 15c. The bottom surface 15a is located radially outward in the receiving groove 15 and extends axially. The one side surface 15b is located on one axial side of the receiving groove 15 and extends radially. The other side surface 15c is located on the other axial side of the receiving groove 15 and extends radially.

[0037] The receiving groove portion 15 is positioned on its inner circumferential surface 2a so as to be adjacent to the inner circumferential surface 12a of the receiving end portion 12 in the other axial direction. As shown in Figure 1, the diameter D15 of the bottom surface 15a of the receiving groove portion 15 is larger than the inner diameter D12 of the receiving end portion 12. In this embodiment, the depth of the receiving groove portion 15 is equal to the difference between the diameter D15 of the bottom surface 15a of the receiving groove portion 15 and the inner diameter D12 of the receiving end portion 12.

[0038] The receiving groove portion 15 contains the receiving groove insertion portion 21 of the sealing member 20 (described later) and the protruding portion 33 of the mounting member 30 (described later).

[0039] (Sealing material) The sealing member 20 is positioned between the inner circumferential surface 2a of the receiving opening 2 and the outer circumferential surface 3a of the insertion opening 3. The sealing member 20 is made of an elastic material such as rubber. The sealing member 20 is an annular member in which the axis of the sealing member 20 coincides with or is parallel to the axis P of the pipe to be joined W1. As shown in Figure 2, the sealing member 20 has an insertion portion 21 inside the receiving groove and a sealing portion 22.

[0040] The insertion portion 21 within the receiving groove is annular and inserted into the receiving groove portion 15. That is, a part of the sealing member 20 is positioned within the receiving groove portion 15 provided on the inner circumferential surface 2a of the receiving opening 2. In this embodiment, the radial thickness of the insertion portion 21 within the receiving groove is equal to the depth of the receiving groove portion 15. The radial thickness of the insertion portion within the receiving groove may be greater than or less than the radial depth of the receiving groove portion.

[0041] Furthermore, the axial length of the insertion portion 21 within the receiving groove is shorter than the width (axial length) of the receiving groove portion 15. In addition to the insertion portion 21 within the receiving groove portion 15, the protruding portion 33 of the mounting member 30, which will be described later, is also positioned within the receiving groove portion 15. Therefore, the width of the receiving groove portion 15 is equal to or greater than the sum of the axial length of the insertion portion 21 within the receiving groove portion 21 and the axial length of the protruding portion 33. As a result, the insertion portion 21 within the receiving groove portion 21 is axially sandwiched between the protruding portion 33 of the mounting member 30 and the other side surface 15c of the receiving groove portion 15.

[0042] Furthermore, the outer circumferential surface of the insertion portion 21 within the receiving groove is in contact with the bottom surface 15a of the receiving groove portion 15, while the inner circumferential surface is in contact with the outer circumferential surface of the retaining portion 31 of the mounting member 30, which will be described later. In other words, as will be described in more detail later, the insertion portion 21 within the receiving groove is pressed radially outward against the bottom surface 15a of the receiving groove portion 15 by the retaining portion 31 of the mounting member 30. As a result, the insertion portion 21 within the receiving groove is pressed against the bottom surface 15a and the other side surface 15c of the receiving groove portion 15 by the mounting member 30, and is therefore fixed to the receiving groove portion 15.

[0043] The sealing portion 22, described later, is connected to the radially inner side of the insertion portion 21 within the receiving groove. Therefore, the insertion portion 21 within the receiving groove is located radially outward from the sealing portion 22.

[0044] As shown in Figure 2, the sealing portion 22 is annular in shape and protrudes radially inward from the other end of the receiving groove insertion portion 21, while remaining radially inside the receiving groove insertion portion 21. The sealing portion 22 is made of an elastic material such as rubber, which is more easily deformable than the receiving groove insertion portion 21.

[0045] When the socket 3 is not inserted into the socket 2, the minimum inner diameter of the sealing portion 22 is smaller than the outer diameter of the socket 3. As a result, the sealing portion 22 in the joint structure 1 is held so as to be radially sandwiched between the inner circumferential surface 2a of the socket 2 and the outer circumferential surface 3a of the socket 3. The sealing portion 22 extends axially while being radially sandwiched between the socket 2 of the pipe to be joined W1 and the socket 3 of the pipe W2. The sealing portion 22 is in contact with the portion of the inner circumferential surface 2a of the socket 2 that is located in the other axial direction from the socket groove portion 15, and is also in contact with the outer circumferential surface 3a of the socket 3. As a result, the sealing portion 22 can axially seal the space between the inner circumferential surface 2a of the socket 2 and the outer circumferential surface 3a of the socket 3.

[0046] (Mounting components) The mounting member 30 is a member for attaching the sealing member 20 to the inner circumferential surface of the receiving opening 2. As shown in Figure 3, the mounting member 30 is an arc-shaped member that has a slit 35 in a part of its circumferential direction and is elastically deformable in the radial and circumferential directions. Specifically, as shown in Figures 1 and 3, the mounting member 30 has an outer diameter D30 that is larger than the inner diameter D21 of the insertion portion 21 of the receiving groove of the sealing member 20 before it is installed inside the pipe to be joined W1.

[0047] The mounting member 30 is elastically deformable radially and circumferentially to narrow the circumferential spacing of the slits 35. This allows the mounting member 30 to be inserted into the socket 2 from the socket end 12 while elastically deformed radially and circumferentially to narrow the circumferential spacing of the slits 35. Furthermore, when the mounting member 30 is positioned on the inner circumferential surface of the socket 2, it attempts to return to its original shape as shown in Figure 3 due to its elastic restoring force. Therefore, this elastic restoring force presses the sealing member 20 radially outward, as will be described in more detail later.

[0048] As shown in Figures 2 and 3, the mounting member 30 has a pressing portion 31, a receiving port contact portion 32, a protruding portion 33, and a slit 35.

[0049] As shown in Figure 2, the retaining portion 31 is located on the axial side of the mounting member 30. The retaining portion 31 is located outside the receiving groove portion 15 and overlaps with the receiving groove portion 15 when viewed radially across the pipe W1 to be joined.

[0050] The pressing portion 31 is in contact with the inner circumferential surface 21a of the insertion portion 21 of the sealing member 20 into the receiving groove. That is, the pressing portion 31 is in contact with the sealing member 20 at a position adjacent to the sealing portion 22 in the axial direction. The pressing portion 31 presses the insertion portion 21 of the sealing member 20 into the receiving groove radially outward relative to the bottom surface 15a of the receiving groove 15 by the elastic restoring force described above.

[0051] The position adjacent to the seal portion 22 in the axial direction refers to a positional relationship in the joint structure 1 such that the seal portion 22 and the retaining portion 31 come into contact when the seal portion 22 is subjected to a force in the axial direction, for example, due to pressure inside the pipe to be joined. Therefore, the retaining portion 31 does not necessarily have to be in contact with the seal portion 22.

[0052] The socket contact portion 32 is located on one axial side of the mounting member 30. The socket contact portion 32 extends axially from the retaining portion 31. When viewing the pipe to be joined W1 radially, the socket contact portion 32 overlaps with the inner circumferential surface 12a of the socket end portion 12, which is located axially to the side of the socket groove portion 15. More specifically, when viewing the pipe to be joined W1 radially, the socket contact portion 32 extends axially from the retaining portion 31 to a position that overlaps with the open end of the socket end portion 12. The outer circumferential surface of the socket contact portion 32 is in contact with the inner circumferential surface 12a of the socket end portion 12.

[0053] The inner circumferential surface of the socket contact portion 32 is an inclined surface 32a. The inclined surface 32a is a surface that changes so that the inner diameter of the socket contact portion 32 decreases from one axial end toward the other axial end, which is the insertion direction of the socket 3 of the pipe W2. In other words, the inner diameter of the socket contact portion 32 decreases from one axial end toward the other axial end of the socket contact portion 32.

[0054] The protruding portion 33 extends radially outward from the entire circumference of the outer surface of the pressing portion 31 toward the receiving groove portion 15. The protruding portion 33 extends radially outward from the outer surface of the pressing portion 31 so that it is located on the opening H side of the receiving opening 2 toward the receiving groove portion 15 toward the receiving groove insertion portion 21. In addition, the protruding portion 33 is in axial contact with one side surface 15b of the receiving groove portion 15 and the receiving groove insertion portion 21 toward the receiving groove portion 15. As a result, the protruding portion 33 can sandwich the receiving groove insertion portion 21 between the other side surface 15c of the receiving groove portion 15. Thus, the receiving groove insertion portion 21 can be fixed to the receiving groove portion 15. In this embodiment, the entirety of the protruding portion 33 is located within the receiving groove portion 15.

[0055] As described above, the mounting member 30 has a pressing portion 31 that presses the inner circumferential surface 21a of the insertion portion 21 in the receiving groove radially outward at a position adjacent to the sealing portion 22 in the axial direction, and a receiving contact portion 32 that contacts the inner circumferential surface 12a of the receiving end portion 12. Furthermore, the mounting member 30 is configured such that the protruding portion 33 is inserted from the pressing portion 31 into the receiving groove portion 15.

[0056] According to the above configuration, the protruding portion 33 axially clamps the insertion portion 21 of the sealing member 20 into the receiving groove portion 15 between itself and the other side surface 15c of the receiving groove portion 15, and the pressing portion 31 is positioned close to the opening H relative to the sealing portion 22. As a result, even if a force is applied to the sealing member 20 that moves it axially toward the opening H, for example, due to water pressure inside the pipe W1 to be joined, the protruding portion 33 can restrict the axial movement of the insertion portion 21 within the receiving groove portion 15, and the pressing portion 31 can restrict the axial movement of the sealing portion 22. Therefore, the mounting member 30 can restrict the axial movement of the sealing member 20.

[0057] In addition, in the above configuration, the pressing portion 31 presses the insertion portion 21 into the receiving groove radially outward against the bottom surface 15a of the receiving groove portion 15. Moreover, the receiving contact portion 32 is in contact with the inner circumferential surface 12a of the receiving end portion 12, and the protruding portion 33 is in contact with one side surface 15b of the receiving groove portion 15. As a result, even if a force is applied to the sealing portion 22 that causes the insertion portion 21 of the sealing member 20 to move radially inward, for example, due to water pressure inside the pipe to be joined W1, the pressing portion 31 can restrict the radial movement of the insertion portion 21 into the receiving groove. Furthermore, if a force is applied to the insertion portion 21 within the receiving groove that moves radially inward, the retaining portion 31 is pushed radially inward by the insertion portion 21 within the receiving groove. However, the receiving contact portion 32 contacts the inner circumferential surface 12a of the receiving end portion 12, and the protruding portion 33 contacts the side surface 15b, thereby restricting the radial inward movement of the mounting member 30. As a result, the mounting member 30 can hold the sealing member 20 radially without moving radially inward, thus restricting the radial movement of the sealing member 20.

[0058] Therefore, the mounting member 30 having the above-described configuration can restrict the axial and radial movement of the sealing member 20.

[0059] (Method of joining pipes to each other) Next, the method of joining pipe W2 and pipe to be joined W1 will be described with reference to Figures 4, 5A, 5B, and 5C. Figure 4 is a flowchart illustrating the method of joining pipe W2 and pipe to be joined W1. Figure 5A is a schematic cross-sectional view showing the placement of the sealing member 20 in the socket groove 15 of the socket 2 of pipe to be joined W1. Figure 5B is a schematic cross-sectional view showing the attachment member 30 to the pipe to be joined W1 in which the sealing member 20 is placed. Figure 5C is a schematic cross-sectional view showing the insertion opening 3 of pipe W2 being inserted into the socket 2 of pipe to be joined W1 in which the sealing member 20 is attached using the attachment member 30. Figures 5A, 5B, and 5C are cross-sectional views of pipe W2 and pipe to be joined W1 cut axially in a plane containing the axis P of pipe W1.

[0060] When the flow shown in Figure 4 starts (START), in step S1, a pipe W2 having an insertion port 3 is prepared, as well as a pipe to be joined W1 having a receiving port 2.

[0061] In the following step S2, as shown in Figure 5A, a lock ring M or the like is attached to the inner circumferential surface 2a of the socket 2 at a position further axially from the opening H of the socket 2 than the position where the seal member 20 is attached. Then, with the seal member 20 reduced in diameter in the radial direction as shown by the black arrow in Figure 5A, the seal member 20 is inserted into the pipe to be joined W1 so that the socket groove insertion portion 21 of the seal member 20 is positioned within the socket groove portion 15 (see the white arrow in Figure 5A).

[0062] Next, in step S3 of the flowchart shown in Figure 4, as shown by the black arrow in Figure 5B, the mounting member 30 is deformed in the circumferential direction to reduce its diameter so as to narrow the circumferential gap of the slit 35 in the mounting member 30, thereby inserting the mounting member 30 into the receiving end 12 (see the white arrow in Figure 5B). After that, with the protruding portion 33 of the mounting member 30 positioned within the receiving groove portion 15 so as to contact the receiving groove insertion portion 21, the mounting member 30 is expanded in diameter. This allows the receiving groove insertion portion 21 of the sealing member 20 to be pressed against the receiving groove portion 15 using the mounting member 30. Thus, the sealing member 20 can be attached to the inner circumferential surface 2a of the receiving end 2.

[0063] Next, in step S4 of the flowchart shown in Figure 4, the insertion port 3 of pipe W2 is inserted axially into the receiving port 2 of pipe W1, as indicated by the white arrow in Figure 5C. At this time, the insertion port 3 is inserted into the receiving port 2 by pressing the sealing portion 22 of the sealing member 20 radially against the inner circumferential surface 2a of the receiving port 2 and pushing the insertion port 3 in the insertion direction (see the black arrow in Figure 5C). As a result, the pipe W1 and pipe W2 are joined with the sealing portion 22 radially sandwiched between the receiving port 2 and the insertion port 3. After that, the flowchart shown in Figure 4 is completed (END).

[0064] The joint structure 1 according to the embodiment described above includes an insertion port 3 of a pipe W2, a receiving port 2 of a pipe to be joined to the pipe W2, and an annular sealing member 20 that seals the space between the outer circumferential surface 3a of the insertion port 3 of the pipe W2 and the inner circumferential surface 2a of the receiving port 2 of the pipe to be joined. The joint structure 1 has a mounting member 30 that extends in the circumferential direction for attaching the sealing member 20 to the inner circumferential surface 2a of the receiving port 2 of the pipe to be joined. The receiving port 2 of the pipe to be joined has a receiving port groove portion 15 that extends in the circumferential direction on its inner circumferential surface 2a. A receiving port groove portion insertion portion 21, which is part of the sealing member 20, is inserted into the receiving port groove portion 15. The mounting member 30 is positioned to contact the inner circumferential surfaces 21a and 2a of the receiving port groove portion insertion portion 21 and the pipe to be joined W1, respectively, and to press the receiving port groove portion insertion portion 21 radially outward against the bottom surface 15a of the receiving port groove portion 15.

[0065] When attaching the sealing member 20 to the inner circumferential surface 2a of the receiving end 2 of the pipe to be joined W1, it is necessary to deform the sealing member 20, which has an outer diameter larger than the inner diameter of the receiving end 12, radially inward while passing it through the opening H of the receiving end 2 of the pipe to be joined W1 in the axial direction, and then install it into the receiving groove 15 formed on the inner circumferential surface 2a of the pipe to be joined W1.

[0066] Here, in the shape of the inner circumferential surface 2a of the socket 2 of the pipe W1 to be joined, if the difference between the diameter D15 of the bottom surface 15a of the socket groove 15 and the inner diameter D12 of the socket end 12 is designed to be small, the depth of the socket groove 15 becomes shallow. When the depth of the socket groove 15 is shallow in this way, the seal member 20 can be inserted into the pipe W1 to be joined with a small amount of deformation that deforms the outer shape of the seal member 20 radially inward. However, if the socket groove 15 is shallow, the seal member 20 is likely to slip out of the socket groove 15 in one axial direction.

[0067] In contrast, according to the configuration of this embodiment, the sealing member 20 can be attached to the inner circumferential surface 2a of the pipe to be joined W1 by the mounting member 30, such that the receiving groove insertion portion 21 of the sealing member 20 is pressed radially outward against the bottom surface 15a of the receiving groove portion 15 of the pipe to be joined W1.

[0068] As a result, even if the depth of the receiving groove 15 is made shallower, for example, the sealing member 20 can be more securely attached to the inner circumferential surface of the pipe to be joined W1 by the mounting member 30. Therefore, since the depth of the receiving groove 15 can be made shallower compared to the conventional configuration, there is no need to deform the sealing member 20 significantly inward in the radial direction when attaching it to the receiving groove 15. Thus, the sealing member 20 can be easily attached to the inner circumferential surface 2a of the pipe to be joined W1.

[0069] Therefore, by using the mounting member 30, a joint structure 1 can be realized in which the sealing member 20 can be more easily attached to the inner circumferential surface 2a of the receiving end 2 of the pipe W1 to be joined.

[0070] Furthermore, in this embodiment, the mounting member 30 is positioned to overlap the receiving groove portion 15 when viewed radially across the pipe to be joined W1, and has a pressing portion 31 that contacts the inner circumferential surface 21a of the receiving groove portion 21 so as to press the receiving groove portion insertion portion 21 of the sealing member 20 radially outward against the bottom surface 15a of the receiving groove portion 15, and a receiving contact portion 32 that extends axially from the pressing portion 31 across the pipe to be joined W1 so as to contact the inner circumferential surface 12a of the inner circumferential surface 2a of the pipe to be joined W1 that is on the receiving opening side of the receiving groove portion 15.

[0071] According to the above configuration, after inserting the receiving groove insertion portion 21 of the sealing member 20 into the receiving groove portion 15 of the pipe to be joined W1, the receiving groove insertion portion 21 is pressed radially outward against the bottom surface 15a of the receiving groove portion 15 by the pressing portion 31 of the mounting member 30, and the sealing member 20 can be fixed to the receiving groove portion 15 by the receiving contact portion 32.

[0072] As a result, the sealing member 20 can be attached to the inner circumferential surface 2a of the pipe to be joined W1 by the pressing portion 31 and the receiving contact portion 32 of the mounting member 30. Thus, a joint structure 1 can be realized in which the sealing member 20 and the mounting member 30 can be attached to the pipe to be joined W1 more easily.

[0073] Furthermore, in this embodiment, the sealing member 20 has a receiving groove insertion portion 21 as part of the sealing member 20 that is inserted into the receiving groove portion 15, and an annular sealing portion 22 that extends radially inward from the receiving groove insertion portion 21 and contacts the outer circumferential surface 3a of the insertion opening 3 of the pipe W2 and the inner circumferential surface 2a of the receiving opening 2 of the pipe to be joined W1. The retaining portion 31 is positioned axially with respect to the sealing portion 22 and is in contact with the inner circumferential surface 21a of the receiving groove insertion portion 21.

[0074] According to the above configuration, the pressing portion 31 is positioned axially relative to the sealing portion 22 and can press the insertion portion 21 into the receiving groove radially outward relative to the receiving groove portion 15. As a result, even if a force such as water pressure inside the pipe to be joined W1 is applied to the sealing portion 22, causing it to press against the opening H of the receiving port 2, the pressing portion 31 presses the insertion portion 21 into the receiving groove radially outward relative to the receiving groove portion 15 while contacting the sealing portion 22, thereby preventing the sealing member 20 from moving axially toward the opening H of the receiving port 2.

[0075] Furthermore, in this embodiment, the mounting member 30 has a protruding portion 33 that extends from the pressing portion 31 toward the receiving groove portion 15.

[0076] According to the above configuration, the protruding portion 33 is located within the receiving groove portion 15. As a result, even if an axial force is applied to the sealing member 20 by, for example, the water pressure inside the pipe W1 to be joined, the sealing member 20 and the mounting member 30 are less likely to move in the axial direction, thus more securely holding the sealing member 20 within the receiving groove portion 15.

[0077] Furthermore, in this embodiment, the receiving port contact portion 32 extends axially from the pressing portion 31 to the opening H end of the receiving port 2 of the pipe to be joined W1.

[0078] This increases the contact area of ​​the receiving contact portion 32 with respect to the inner circumferential surface 2a of the pipe W1 to be joined. Therefore, the mounting member 30 can more stably hold the sealing member 20 against the inner circumferential surface 2a of the pipe W1 to be joined. Thus, a joint structure 1 is provided in which the sealing member 20 is less likely to come off the inner circumferential surface 2a of the pipe W1 to be joined.

[0079] Furthermore, in this embodiment, the inner circumferential surface of the socket contact portion 32 includes an inclined surface 32a in which the inner diameter decreases from one axial end, which is the end on the socket opening side, to the other axial end, which is the insertion direction of the pipe W2.

[0080] According to the above configuration, by inserting the insertion end 3 of pipe W2 into the pipe to be joined W1 while bringing the insertion end 3 of pipe W2 into contact with the inclined surface 32a of the receiving end contact portion 32, the insertion end 3 of pipe W2 can be joined to the receiving end 2 of pipe W1 while being centered with respect to the receiving end 2 of pipe W1. Therefore, the mounting member 30 can prevent misalignment of the sealing member 20, and a joint structure 1 can be provided that allows the insertion end 3 of pipe W2 to be joined to the receiving end 2 of pipe W1 more easily.

[0081] [Modified examples of embodiments] Referring to Figures 6 and 7, the configuration of the joint structure 100 according to a modified example of the above embodiment will be described. Figure 6 is an end view showing the schematic configuration of the joint structure 100 according to a modified example of the above embodiment. Figure 7 is a partially enlarged view of the joint structure 100 shown in Figure 6. In the following, components similar to those in the above embodiment will be denoted by the same reference numerals, and their descriptions will be omitted. Only components different from the above embodiment will be described.

[0082] As shown in Figures 6 and 7, the modified joint structure 100 has an insertion port 3 for pipe W2, a receiving port 2 for the pipe to be joined W1, a sealing member 120, and a mounting member 130. As shown in Figure 7, the sealing member 120 has a receiving port groove insertion portion 121 and a sealing portion 22. The mounting member 130 has a pressing portion 131, a receiving port contact portion 32, a protruding portion 133, and a slit 35.

[0083] The receiving groove insertion portion 121 has a main body portion 124 and a notch portion 125. The main body portion 124 is positioned within the receiving groove portion 15. The main body portion 124 is in contact with the bottom surface 15a, one side surface 15b, and the other side surface 15c of the receiving groove portion. The inner circumferential surface of the main body portion 124 is provided with a notch portion 125 that extends around the entire circumference in the axial direction at the axial center. That is, the notch portion 125 is a groove formed on the inner circumferential surface of the receiving groove insertion portion 121 that is located axially to the side of the sealing portion 22.

[0084] The retaining portion 131 of the mounting member 130 is cylindrical in shape and extends in the axial direction. When viewed radially across the pipe to be joined W1, the retaining portion 131 overlaps the receiving groove portion 15 and also overlaps the notch portion 125. The retaining portion 131 is in contact with the inner circumferential surface 121a of the main body portion 124 located on one axial side of the notch portion 125.

[0085] The protruding portion 133 projects radially outward from the outer circumferential surface of the pressing portion 131 toward the notch 125 of the sealing member 120. The protruding portion 133 is located within the notch 125 of the insertion portion 121 and is in contact with the inner surface of the notch 125. In this modified example, the entire protruding portion 133 is located within the notch 125. Since the main body portion 124 of the insertion portion 121, which is provided with the notch 125, is located within the insertion portion 15, the protruding portion 133 is also located within the insertion portion 15 when it is located within the notch 125.

[0086] In this modified example, the mounting member 130 does not come into contact with the inner circumferential surface of the receiving groove portion 15, and only the main body portion 124 of the receiving groove insertion portion 121 of the sealing member 120 comes into contact with it. Therefore, the contact area of ​​the receiving groove insertion portion 121 of the sealing member 120 with respect to the inner surface of the receiving groove portion 15 is larger than the contact area of ​​the receiving groove insertion portion 21 of the sealing member 20 with respect to the inner surface of the receiving groove portion 15 in the joint structure 1 according to the above embodiment.

[0087] In the modified joint structure 100 described above, the insertion portion 121 within the receiving groove has a notch 125 in which a part of the inner circumferential surface of the insertion portion 121 within the receiving groove has been cut out. The protruding portion 133 of the mounting member 130 protrudes from the retaining portion 131 toward the notch 125 and is located within the receiving groove portion 15 and within the notch 125.

[0088] According to the above configuration, the protruding portion 133 that protrudes from the retaining portion 131 of the mounting member 130 is inserted into the notch 125, which is a part of the inner circumferential surface of the receiving groove insertion portion 121 of the sealing member 120, and into the receiving groove portion 15.

[0089] This allows the insertion portion 121 of the sealing member 120 into the receiving groove to be sandwiched between the protruding portion 133 of the mounting member 130 and the bottom surface 15a of the receiving groove portion 15. Thus, the sealing member 120 can be securely fixed to the inner circumferential surface 2a of the receiving opening 2 of the pipe to be joined.

[0090] Furthermore, compared to the embodiment described above where the protruding portion is not inserted into the notch, the contact area between the sealing member 120 and the mounting member 130 increases. Therefore, separation of the sealing member 120 and the protruding portion 133 can be prevented more reliably.

[0091] Furthermore, in the modified joint structure 100, the pressing portion 131 presses radially outward against the inner circumferential surface 121a of the main body portion 124 of the insertion portion 121 in the receiving groove, which is located on one axial side of the notch portion 125, and also presses radially outward against the inner circumferential surface 121b of the main body portion 124 of the insertion portion 121 in the receiving groove, which has the notch portion 125 formed therein, via the protruding portion 133.

[0092] This allows the mounting member 130 to more reliably prevent misalignment of the sealing member 120 relative to the receiving groove 15.

[0093] (Other embodiments) Although embodiments of the present invention have been described above, the embodiments described above are merely examples for carrying out the present invention. Therefore, the invention is not limited to the embodiments described above, and it is possible to carry out the invention by appropriately modifying the embodiments described above without departing from the spirit of the invention.

[0094] In the above embodiment and the above modification, the receiving groove portion 15 is positioned on the inner circumferential surface 2a of the receiving opening 2, adjacent to the inner circumferential surface 12a of the receiving end portion 12 in the other axial direction. The receiving groove portion 15 has a substantially rectangular cross-section. The receiving groove insertion portions 21 and 121 of the sealing members 20 and 120 are configured to be insertable into the receiving groove portion 15. The protruding portions 33 and 133 of the mounting members 30 and 130 are configured to be located within the receiving groove portion 15. However, the receiving groove portion may be located anywhere in the axial direction on the inner circumferential surface of the receiving opening. The receiving groove portion may be located, for example, at a position axially away from the inner circumferential surface of the receiving end portion. The receiving groove portion may have a shape other than substantially rectangular, as long as the axial cross-section is recessed radially outward. The receiving groove portion may have a shape, for example, a curved axial cross-section. In this case, the receiving groove insertion portion of the sealing member is provided to be insertable into the receiving groove portion.

[0095] In the above embodiment and the above modified example, the mounting members 30 and 130 have protrusions 33 and 133. However, the mounting members do not need to have protrusions.

[0096] In the above embodiment and its modifications, all of the protrusions 33,133 are located within the receiving groove 15. However, it is sufficient that at least a portion of the protrusions are located within the receiving groove. In other words, for example, a portion of the protrusions may be located outside the receiving groove.

[0097] In the modified example described above, the entire protrusion 133 is located within the notch 125 and within the receiving groove 15. However, it is sufficient that at least a portion of the protrusion is located within the notch and within the receiving groove. In other words, for example, a portion of the protrusion may be located outside the receiving groove or the notch.

[0098] In the above embodiment and the above modification, the pressing portions 31 and 131 are in contact with the inner circumferential surfaces 21a and 121a of the insertion portions 21 and 121, at a position adjacent to the seal portion 22 in one axial direction, so as to press the inner circumferential surfaces 21a and 121a of the insertion portions 21 and 121 radially outward against the bottom surface 15a of the insertion portion 15. However, a part of the pressing portion does not have to be located adjacent to the seal portion in one axial direction. Also, a part of the pressing portion does not have to be in contact with the inner circumferential surface of the insertion portion in the insertion portion so as to press it radially outward against the inner circumferential surface.

[0099] In the above embodiment and the above modified example, the mounting members 30, 130 have a socket contact portion 32. The socket contact portion 32 overlaps with the inner circumferential surface 12a of the socket end 12 when viewed radially across the pipe to be joined W1. The outer circumferential surface of the socket contact portion 32 is in contact with the inner circumferential surface 12a of the socket end 12. However, the socket contact portion may overlap with the inner circumferential surface of the socket other than the inner circumferential surface of the socket end when viewed radially across the pipe to be joined. It is sufficient that at least a part of the outer circumferential surface of the socket contact portion is in contact with the inner circumferential surface of the socket. Alternatively, the mounting member may not have a socket contact portion, and it is sufficient that a part of the mounting member is in contact with some part of the inner circumferential surface of the socket.

[0100] In the above embodiment and the above modification, an inclined surface 32a is formed on the inner circumferential surface of the receiving contact portion 32. However, the receiving contact portion does not necessarily have to have an inclined surface. [Industrial applicability]

[0101] The present invention can be used in a joint structure having a pipe insertion port, a receiving port of a pipe to be joined to the pipe, and an annular sealing member that seals the space between the outer circumferential surface of the pipe insertion port and the inner circumferential surface of the receiving port of the pipe to be joined. [Explanation of Symbols]

[0102] 1. 100 Joint Structure W1 Joined pipe 2 socket 2a Inner surface 12 Socket end 12a Inner surface 14 grooves for lock rings 15 Socket groove 15a Bottom 15b One side side 15a Other side side W2 tube 3. Insertion port 3a Outer surface 20, 120 sealing members 21, 121 Insertion part inside the receiving groove 22 Seal part 30, 130 Mounting parts 31, 131 Pressing part 32 Socket contact part 32a Slope 33, 133 protrusion 35 slits 124 Main body 125 Notch M Lock Ring P axis

Claims

1. A joint structure comprising a pipe insertion port, a receiving port of a pipe to be joined to the pipe, and an annular sealing member that seals the space between the outer surface of the pipe insertion port and the inner surface of the receiving port of the pipe to be joined, The pipe to be joined has a mounting member that extends circumferentially to fix the sealing member on the inner circumferential surface of the receiving end, The receiving end of the pipe to be joined has a receiving end groove portion extending in the circumferential direction on its inner circumferential surface, A portion of the sealing member is inserted into the receiving groove, The aforementioned mounting member is The sealing member is positioned to contact a portion of the sealing member and the inner circumferential surface of the pipe to be joined, and to press a portion of the sealing member radially outward against the bottom surface of the receiving groove. Joint structure.

2. In the joint structure described in claim 1, The aforementioned mounting member is When viewed radially, the pipe to be joined has a pressing portion located in a position overlapping the receiving groove, and at least a portion of it contacts the inner circumferential surface of a part of the sealing member such that it presses a part of the sealing member radially outward against the bottom surface of the receiving groove, A receiving port contact portion extends from the pressing portion in the axial direction of the pipe to be joined so as to contact the inner circumferential surface of the pipe to be joined that is on the receiving port opening side of the receiving port groove portion, Having, Joint structure.

3. In the joint structure described in claim 2, The sealing member is A receiving groove insertion portion which is part of the sealing member inserted into the receiving groove portion, An annular sealing portion extending radially inward from the insertion portion within the receiving groove, which contacts the outer circumferential surface of the insertion opening of the pipe and the inner circumferential surface of the receiving opening of the pipe to be joined, It has, The aforementioned pressing portion is At least a portion of it is positioned in the axial direction relative to the sealing portion and is in contact with the inner circumferential surface of the insertion portion within the receiving groove. Joint structure.

4. In the joint structure described in claim 3, The aforementioned mounting member is The pressing portion further has a protruding portion that extends into the receiving groove portion. Joint structure.

5. In the joint structure described in claim 4, The insertion portion within the receiving groove has a notch in which a part of the inner circumferential surface is cut out. At least a portion of the aforementioned protrusion is A portion that protrudes from the pressing portion toward the notch portion and is located within the receiving groove portion and within the notch portion, Joint structure.

6. In the joint structure described in claim 2, The aforementioned receiving contact portion is, The pressing portion extends in the axial direction from the receiving end of the pipe to be joined, Joint structure.

7. In the joint structure described in claim 6, The inner circumferential surface of the socket contact portion includes an inclined surface in which the inner diameter decreases from the end on the socket opening side in the direction of insertion of the pipe. Joint structure.

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