Retaining ring and pipe fitting equipped therewith

Abstract

The present invention provides a retaining ring for pipe fittings that facilitates pipe insertion and prevents pipes from falling out, and a pipe fitting using the same. [Solution] The retaining ring 40 attached to the pipe fitting 10 of the present invention has a plurality of claws 42 protruding inward from the inner circumference side of an annular ring portion 41, and is a retaining ring attached to a pipe fitting to which a pipe 60 is connected, and the claws have a flat portion 44 extending horizontally from the ring portion and a claw 46 that is bent diagonally from the flat portion toward the direction of insertion of the pipe.

Description

Technical Field

[0001] The present invention relates to a retaining ring for a pipe joint and a pipe joint provided with the same.

Background Art

[0002] A retaining ring is used for a pipe joint that connects resin water supply pipes, drainage pipes, etc. to make it difficult for the pipe to come off. For example, the retaining ring has claws protruding obliquely inward on the inner circumference of the annular ring portion in the direction of pipe insertion. When the pipe is inserted into the joint, the claws are expanded by the outer circumference of the pipe. When the pipe moves in the removal direction, the tip of the claw pierces into the pipe to prevent the pipe from coming off (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Disclosure of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, there is almost no gap between adjacent claws. That is, the ratio of the claws to the inner circumference length of the ring portion is very large. As a result, it is difficult for the pipe to come off, but especially for a pipe with a large outer diameter, the resistance of the claws when inserting the pipe becomes large, making it difficult to manually insert the pipe into the joint, and the workability is poor.

[0005] An object of the present invention is to provide a retaining ring for a pipe joint that allows easy insertion of the pipe and can also prevent the pipe from falling off, and a pipe joint using the same.

Means for Solving the Problems

[0006] The retaining ring to be attached to the pipe joint of the present invention is A retaining ring for pipe fittings to which pipes are connected, having multiple claws protruding inward from the inner circumference of an annular ring portion, The claw body has a flat portion extending horizontally from the ring portion, A claw that is bent diagonally from the flat portion toward the insertion direction of the pipe, It is equipped with.

[0007] The aforementioned claw bodies are formed with a gap between them and adjacent claw bodies. It is desirable that the proportion of the claw body to the inner circumference of the ring portion is 40% to 60%.

[0008] The claw body preferably has a flat portion length of 1 mm to 8 mm and a claw length of 3 mm to 9 mm.

[0009] The tip of the aforementioned claw should preferably have a split shape.

[0010] Furthermore, the pipe fitting of the present invention is Having an opening on at least one side, A rubber ring is fitted onto the inner surface of the aforementioned socket. A cover member for holding down the rubber ring is attached to the tip side of the receiving opening. A pipe fitting, The retaining ring is inserted between the rubber ring and the cover member.

[0011] Furthermore, the joint structure of the present invention is The pipe is connected to the socket of the above-mentioned pipe fitting. [Effects of the Invention]

[0012] The retaining ring of the present invention, by having the claw body configured as described above, prevents the pipe from detaching from the pipe fitting when attached to the pipe fitting, while also making it easier to insert the pipe into the pipe fitting. [Brief explanation of the drawing]

[0013] [Figure 1]FIG. 1 is a cross-sectional view of a pipe joint with a retaining ring according to the present invention. [Figure 2] FIG. 2 is a perspective view of the retaining ring according to the present invention. [Figure 3] FIG. 3 is a plan view of the retaining ring. [Figure 4] FIG. 4 is a side view of the retaining ring. [Figure 5] FIG. 5 is a bottom view of the retaining ring. [Figure 6] FIG. 6 is (a) a cross-sectional view taken along line A-A of FIG. 3 and (b) an end view taken along line B-B of FIG. 3. [Figure 7] FIG. 7 is a cross-sectional view of a joint structure in which a pipe is connected to a pipe joint with a retaining ring. [Figure 8] FIG. 8 shows the shape of the claw portion of the retaining ring.

MODE FOR CARRYING OUT THE INVENTION

[0014] Hereinafter, the retaining ring 40 according to the present invention and the pipe joint 10 with the retaining ring 40 will be described with reference to the drawings.

[0015] <Pipe joint 10> The pipe joint 10 of the present invention (hereinafter simply referred to as "joint") has a receiving port 12 formed at the tip of a pipe portion 11 through which fluid can flow, as shown in FIG. 1. The receiving port 12 has a larger diameter than the pipe portion 11, and a rubber ring 20 is fitted on the inner surface. A retaining ring 40 is disposed at the tip of the receiving port 12, and a cover member 30 is attached so as to cover the receiving port 12. The joint 10 can be formed, for example, by injection molding from a polypropylene resin (PP), a vinyl chloride resin (PVC), or the like. When heat resistance and chemical resistance are required for the joint 10, a polypropylene resin is preferable.

[0016] The joint 10 can be a socket type or an elbow type provided with receiving ports 12 at both ends, or a branch joint such as a confluent joint or a cheese type joint having three or more receiving ports 12. Further, the joint 10 may have a form in which one end is closed.

[0017] As a specific embodiment, the socket 12 has a cylindrical portion 13 that widens at the tip of the pipe portion 11, as shown in Figure 1. The pipe 60 is inserted into the cylindrical portion 13, as shown in Figure 2. The tip of the cylindrical portion 13 has a further widened rubber ring mounting cylinder 15. A rubber ring 20 is fitted into the rubber ring mounting cylinder 15. The inner diameter of the cylindrical portion 13 can be determined according to the outer diameter of the pipe 60, which will be described later.

[0018] <Rubber ring 20> As shown in Figure 7, which will be described later, the rubber ring 20 is a member that elastically deforms when the pipe 60 is inserted, conforming tightly to the outer surface of the pipe 60 and holding the pipe 60. As a specific embodiment of the rubber ring 20, as shown in Figure 1, an example can be provided in which a lip portion 22 is provided protruding inward from an annular base portion 21 that abuts against the inner surface of the rubber ring mounting cylinder 15. Of course, the configuration of the rubber ring 20 is not limited to this. In the rubber ring 20 of Figure 1, the lip portion 22 protrudes inward beyond the outer diameter of the pipe 60, and when the pipe 60 is inserted into the cylinder portion 13, the lip portion 22 is pushed outward by the outer surface of the pipe 60, thereby holding the pipe 60.

[0019] The rubber ring 20 can be made of synthetic rubber such as styrene-butadiene rubber (SBR), chloroprene rubber (CR), ethylene-propylene diene rubber (EPDM), fluororubber (FKM), or silicone rubber (VMQ). For heat-resistant applications, ethylene-propylene diene rubber, silicone rubber, or fluororubber can be used.

[0020] <Retaining ring 40> The fitting 10 is equipped with a retaining ring 40 on the tip side of the socket 12. The retaining ring 40 has a number of inwardly facing claws 42, which flex to hold the pipe 60 when the pipe 60 is inserted into the fitting 10, and when the inserted pipe 60 moves in the direction of removal, the tips of the claws 42 pierce the outer surface of the pipe 60, preventing the pipe 60 from falling out of the fitting 10.

[0021] The retaining ring 40 is made from a metal plate such as stainless steel with a thickness of 0.3 mm to 1 mm, and has numerous claws 42 protruding inward from the inner circumferential surface of the annular ring portion 41. The tips of the claws 42 shown in the figure have a split shape (see Figure 8(a)).

[0022] As shown in Figure 1, the retaining ring 40 is positioned on the tip side of the rubber ring 20 of the socket 12 of the joint 10. In the illustration, the retaining ring 40 is positioned so that the ring portion 41 is sandwiched between the end face of the socket 12 and the inner flange 33 of the cover member 30.

[0023] Specific embodiments of the retaining ring 40 are shown in Figures 2 to 5, as well as in the cross-sectional view 6(a) along line AA in Figure 3 and the end view 6(b) along line BB in Figure 3. As shown in the figures, the claw body 42 includes a flat portion 44 extending inward from the ring portion 41 in a direction parallel to the ring portion 41, and a claw 46 extending diagonally from the inner end of the flat portion 44. The boundary between the ring portion 41 and the flat portion 44 is called the base portion 43, and the boundary between the flat portion 44 and the claw 46 is called the bent portion 45. As shown in Figure 7, when the claw 46 is attached to the joint 10, it is inclined toward the insertion direction of the pipe 60.

[0024] The claw body 42 does not form the claw 46 directly and diagonally from the ring portion 41, but rather extends a flat portion 44 from the ring portion 41 and forms the claw 46 at the tip of the flat portion 44. This is to make the claw body 42 more flexible when the pipe 60 is inserted into the fitting 10, by setting the fulcrum for the bending of the claw body 42 far from the tip of the claw 46. As the outer diameter of the pipe 60 increases, the diameter of the retaining ring 40 also increases, so if the claw body 42 is difficult to bend, it becomes even more difficult to insert the pipe 60 into the fitting 10 by hand. Therefore, this embodiment is particularly suitable for use with fittings 10 used for large-diameter pipes 60 with diameters of 48 mm to 114 mm.

[0025] When the claws are formed diagonally directly from the ring portion, the pivot point for the bending of the claws becomes the bend between the ring portion and the claw, and the distance between the tip of the claw and the pivot point becomes shorter, making it difficult for the claws to bend. For this reason, with the same number of claws and claw width, it becomes more difficult to insert the tube 60 compared to the claw body 42 of this embodiment.

[0026] As shown in Figure 3, for the retaining ring 40, the outer diameter of the ring portion 41 is φ1, and the inner diameter to the tip of the claw body 42, i.e., the claw 46, is φ2. In this case, φ1 is the diameter that can be inserted into the cover member 30, and φ2 is smaller than the diameter of the pipe 60 so that it can bend when it comes into contact with the pipe 60 to be inserted. φ2 is set to be 1 mm to 10 mm, preferably 3 mm to 6 mm smaller than the outer diameter of the pipe 60. For example, if the outer diameter of the pipe 60 is 89 mm, it is preferable that φ2 be approximately 86 mm. If φ2 is larger than this, the claw body 42 may not come into contact with the pipe 60, or even if it does, it may hardly bend, resulting in weak fixation. On the other hand, if φ2 is smaller than this, it becomes difficult to insert the pipe 60 manually, reducing workability.

[0027] Furthermore, if the proportion of the claws 42 relative to the inner circumference of the retaining ring 40 is small, the pipe 60 is easy to insert, but the fixing strength of the pipe 60 decreases. Conversely, if the proportion of the claws 42 increases, the pipe 60 becomes difficult to insert, reducing workability, while the fixing strength of the pipe 60 improves. The proportion of the claws 42 is determined by the number of claws 42 and the width of each claw 42. To ensure that the pipe 60 is easy to insert and that the fixing strength of the pipe 60 is secured, it is preferable for the proportion of the claws 42 to be 30% to 70%, and more preferably 40% to 60%. In the illustrated embodiment, there are 24 claws 42, and the width of each claw 42 is 6 mm, so the proportion of the claws 42 is approximately 45%.

[0028] Furthermore, it is desirable that the bent portion 45, which is the boundary between the flat portion 44 and the claw 46, be configured to be located on the inner circumference side of the end face of the rubber ring 20, as shown in Figure 1. This is to prevent interference between the claw 46 and the rubber ring 20 when the claw 46 bends upon contact with the pipe 60.

[0029] Specifically, as shown in Figure 6, when the width of the ring portion 41 of the retaining ring 40, that is, the length from the outer circumference to the base portion 43, is L1, the length of the flat portion 44, that is, the length from the base portion 43 to the bent portion 45, is L2, and the length of the claw 46, that is, the length from the bent portion 45 to the tip, is L3, these dimensions are preferably as follows.

[0030] For example, for large-diameter pipes 60 with an outer diameter of 48 mm to 114 mm, the width L1 of the ring portion 41 is a length that can be sandwiched between the tip of the receiving end 12 and the cover member 30. For example, for large-diameter pipes 60 with an outer diameter of 48 mm to 114 mm, L1 is 3 mm to 7 mm, preferably 4 mm to 6 mm.

[0031] Furthermore, as described above, the length L2 of the flat portion 44 is such that the bent portion 45 is located on the inner circumference side of the end face of the rubber ring 20 in order to avoid interference with the rubber ring 20. As will be explained later, the base portion 43 serves as the fulcrum for the bending of the claw body 42, so it is desirable to make the base portion 43 long. Therefore, for large diameter pipes with an outer diameter of 48 mm to 114 mm, L2 is 1 mm to 8 mm, preferably 1.5 mm to 7.5 mm.

[0032] The length L3 of the claw 46 is the length that reaches the outer circumference of the pipe 60 when the angle θ between the flat portion 44 and the claw 46, as described below, is set so that it protrudes inward from the outer diameter of the pipe 60 by 1 mm to 10 mm, preferably 3 mm to 6 mm. For large diameter pipes with an outer diameter of 48 mm to 114 mm, for example, L3 is 3 mm to 9 mm, preferably 3.5 mm to 8.5 mm.

[0033] The length of the claw body 42 is the sum of the lengths of the flat section 44 and the claw 46 (L2 + L3). If the claw body 42 is long, it will bend more easily, making it easier to insert the pipe 60, but the pipe 60 will also be more likely to come out. Conversely, if the claw body 42 is short, it will bend less, making it difficult to insert the pipe 60, resulting in poor workability. For the above pipe diameter, the length of the claw body 42 (L2 + L3) is preferably 4mm to 17mm, and preferably 5mm to 16mm. The ratio of the lengths of the flat section 44 and the claw 46 is preferably L2:L3 = 30:70 to 70:30, and preferably L2:L3 = 40:60 to 60:40. If one is too long compared to the other, there is a risk of reduced strength.

[0034] Regarding the claw body 42, as shown in Figure 6, when the angle between the flat portion 44 and the claw 46 is θ, it is preferable that θ be between 45° and 65°. If θ is greater than 65°, the angle of the claw 46 with respect to the pipe 60 being inserted is shallow, making it easier to insert the fitting 10, but when the pipe 60 moves in the withdrawal direction, the claw 46 may not penetrate the pipe 60 and may come out. Conversely, if θ is less than 45°, the resistance of the claw 46 when inserting the pipe 60 becomes large, making it time-consuming to insert the pipe 60, or it may not be possible to insert it manually, resulting in poor workability.

[0035] <Cover member 30> In the embodiment shown in Figure 1, a cover member 30 is attached to the tip of the socket 12 to prevent the rubber ring 20 fitted into the socket 12 and the retaining ring 40 at the tip of the socket 12 from falling off. The cover member 30 has a sleeve 31 that fits around the outer circumference of the socket 12 and an inner flange 33 that protrudes inward from the tip of the sleeve 31. The inner flange 33 has a hole 34 in the center into which the pipe 60 can be inserted. When the sleeve 31 is fitted around the outer circumference of the socket 12, the inner flange 33 closes the outer circumference of the rubber ring mounting cylinder 15 of the socket 12, preventing the rubber ring 20 and the retaining ring 40 from falling off.

[0036] The cover member 30 can be attached to the sleeve 31 by engagement, screwing, or adhesive. In Figure 1, the cover member 30 is attached to the socket 12 by engagement. Specifically, engagement protrusions 14 and 32 are formed on the inner surface of the sleeve 31 and the outer surface of the socket 12, respectively, and the cover member 30 can be attached by pushing the cover member 30 into the socket 12, thereby engaging the engagement protrusions 14 and 32 with each other. Since the cover member 30 is configured to be attached after the rubber ring 20 and retaining ring 40 are attached, multiple types of rubber rings 20 and retaining rings 40 can be prepared, and by attaching the rubber ring 20 and retaining ring 40 according to the required performance to the socket 12 and then attaching the cover member 30, joints 10 with different performance can be provided.

[0037] Furthermore, if the joint 10 is formed by insert molding on the rubber ring 20 and the retaining ring 40, the cover member 30 is not required.

[0038] <Fabrication of joint 10> As shown in Figure 1, the joint 10 is manufactured by fitting the rubber ring 20 into the rubber ring mounting cylinder 15 of the socket 12, placing the retaining ring 40 on the tip of the socket 12, and attaching the cover member 30.

[0039] <Tube 60> The pipe 60 fitted to the fitting 10 in the above configuration can have various outer and inner diameters depending on the application. The inner diameter of the cylindrical portion 13 of the fitting 10 should be matched to that of the pipe 60.

[0040] The pipe 60 can have an outer diameter of, for example, 48 mm to 114 mm. The pipe 60 can be made of the same polypropylene resin as the fitting 10, or it may be made of polyvinyl chloride resin or steel pipe. Furthermore, the pipe 60 may be a single-layer pipe or a multi-layer pipe. In Figure 7, the pipe 60 has a two-layer structure with the inner circumference 61 being polypropylene and the outer circumference 62 being polypropylene mixed with glass fibers, but it may also have a structure of three or more layers.

[0041] <Joint structure 50> To attach the pipe 60 to the fitting 10, simply insert the tip of the pipe 60 into the hole 34 of the inner flange 33 of the fitting 10 and push it in by hand. The pipe 60 enters the cylindrical part 13 while compressing the lip portion 22 of the rubber ring 20. By pushing it in until the tip of the pipe 60 touches the base end of the cylindrical part 13, the pipe 60 is inserted into the cylindrical part 13, and a fitting structure 50 is obtained in which the rubber ring 20 and the retaining ring 40 prevent it from coming loose, as shown in Figure 7.

[0042] In the retaining ring 40 of the present invention, the claw body 42 has a configuration in which a claw 46 is formed at the tip of a flat portion 44. When the tip of the claw 46 is pushed outward, the claw body 42 flexes with the base 43 shown in Figure 6 as a fulcrum. Because the distance between the tip of the claw 46 and the base 43 which acts as a fulcrum is relatively long, the resistance of the claw 46 when inserting the pipe 60 can be reduced compared to when the claw is formed directly on the ring portion, and the pipe 60 can be easily inserted even by hand. Furthermore, the inserted pipe 60 enters the cylindrical portion 13 while compressing the lip portion 22 of the rubber ring 20. Then, by pushing the pipe 60 until its tip hits the base end of the cylindrical portion 13, the pipe 60 is inserted into the cylindrical portion 13, and a joint structure 50 is obtained in which the claw body 42 and rubber ring 20 prevent it from coming loose. When a force is applied to the pipe 60 in the pulling direction, the claw 46 of the claw body 42 pierces the pipe 60, preventing it from coming loose.

[0043] <Tip shape of claw 46> Figure 8 shows examples of the tip shapes of the claws 46 of the claw body 42. Figure 8(a) shows the claw shape used in the retaining ring 40 shown in Figure 2, etc., which is a split shape with two tips. Figure 8(b) shows a shape in which the tip of the claw 46 is rectangular. Figure 8(c) shows a shape in which the claw 46 is pointed toward the center. In any of these shapes, the pipe 60 can be fixed stably, but the configuration in Figure 8(c) is easy to insert into the pipe 60 and difficult to remove, followed by Figure 8(a) and then Figure 8(b). [Examples]

[0044] <Example 1> A joint was fabricated using the retaining ring 40 with the shape shown in Figures 2 to 6 of the present invention (Examples 1 and 2 of the invention) and the retaining ring of Comparative Example 1, and it was evaluated whether the pipe 60 could be inserted manually.

[0045] Invention Example 1 is a retaining ring 40 made from a stainless steel plate with a thickness of 0.5 mm, having an outer diameter φ1 (see Figure 3) of 114 mm, an inner diameter φ2 to the tip of the claw 46 of 85.9 mm, and a ring portion 41 length L1 of 5.5 mm. The claw body 42 occupies 45% of the inner circumference of the ring portion 41, the length L2 of the flat portion 44 is 5 mm, the length L3 of the claw 46 is 7.2 mm, and the angle θ between the flat portion 44 and the claw 46 is 60°. The tip of the claw 46 has a split shape as shown in Figure 8(a).

[0046] The retaining ring 40 of Invention Example 2 has a rectangular shape at the tip of the claw 46 as shown in Figure 8(b), and is otherwise the same as Invention Example 1.

[0047] The retaining ring of Comparative Example 1 has a configuration in which claws are directly attached to the ring portion. Specifically, the ring portion 41 of Invention Example 1 is extended to the bent portion 45. Otherwise, it is the same as Invention Example 1.

[0048] A joint was fabricated by installing these retaining rings between the socket 12 and the cover member 30, as shown in Figure 1.

[0049] Next, a pipe 60 with a diameter of 89 mm was prepared, and the ease of insertion into the fitting was compared. As a result, pipe 60 could be easily inserted by hand in Invention Example 1 and Invention Example 2. However, insertion by hand was difficult in Comparative Example 1. In all Invention Examples, the claw body 42 has not only a claw 46 but also a flat portion 44, so when the pipe 60 is inserted, the fulcrum of the bending becomes the base portion 43 which is the boundary between the flat portion 44 and the ring portion 41, and since the fulcrum is located far from the tip of the claw 46, it was made easier to bend, which is thought to be why the pipe 60 could be easily inserted. On the other hand, in Comparative Example 1, the claw (corresponding to reference numeral 46 in Invention Example) is formed directly from the ring portion 41, so the fulcrum of the bending becomes the part where the claw is bent from the ring portion (corresponding to reference numeral 45 in Invention Example), and since the tip of the claw and the fulcrum are close together, it is thought that it was difficult to bend, and the pipe 60 could not be easily inserted.

[0050] Comparing Invention Example 1 and Invention Example 2, it was easier to insert the tube 60 in Invention Example 1. This is thought to be because, in Invention Example 1, the claws 46 made contact with the tube 60 at the two split points, distributing the resistance force.

[0051] <Example 2> Furthermore, the joint structures 50 of Invention Examples 1 and 2 and Comparative Example 1 were fabricated by inserting the pipe 60, and the resistance of the pipe 60 to coming loose was evaluated by a full-water test. The full-water test is a test in which one socket 12 of the joint 10 is blocked, and water is supplied from the pipe 60 at a predetermined pressure to check for leakage.

[0052] The water pressure was set to 0.2 MPa, the standard for drain pipes, and the test was conducted to see if there was any leakage after 10 minutes. As a result, no leakage was detected in any of the cases. Therefore, it can be concluded that all of the fittings meet the performance requirements for use as drain pipe fittings.

[0053] Furthermore, when the water pressure was double the standard value, 0.4 MPa, some joint detachment was observed in Invention Examples 1 and 2, but no joint detachment was observed in Comparative Example 1. Comparative Example 1 had a configuration that made it less likely to detach because the claws were less prone to bending.

[0054] The above description is for the purpose of explaining the present invention and should not be interpreted as limiting or restricting the scope of the invention described in the claims. Furthermore, it goes without saying that the configuration of each part of the present invention is not limited to the above embodiments and can be modified in various ways within the technical scope described in the claims. [Explanation of symbols]

[0055] 10 Drain pipe fittings 12 socket 13 Cylinder part 20 rubber rings 30 Cover component 40 Retaining ring 41 Ring section 42 Nail body 44 Flat area 46 claws 50 Joint Structure 60 tubes

Claims

1. A retaining ring for pipe fittings to which pipes are connected, having multiple claws protruding inward from the inner circumference of an annular ring portion, The claw body has a flat portion extending horizontally from the ring portion, A claw that is bent diagonally from the flat portion toward the insertion direction of the pipe, Equipped with, A retaining ring that is attached to pipe fittings.

2. The aforementioned claw bodies are formed with a gap between them and adjacent claw bodies. The proportion of the claw body to the inner circumference of the ring portion is 40% to 60%. A retaining ring to be attached to a pipe fitting as described in claim 1.

3. The claw body has a flat portion length of 1 mm to 8 mm and a claw length of 3 mm to 9 mm. A retaining ring to be attached to a pipe fitting according to claim 2.

4. The tip of the aforementioned claw has a split shape. A retaining ring to be attached to a pipe fitting according to claim 3.

5. Having an opening on at least one side, A rubber ring is fitted onto the inner surface of the aforementioned socket. A cover member for holding down the rubber ring is attached to the tip side of the receiving opening. Pipe fittings, A retaining ring according to any one of claims 1 to 4 is inserted between the rubber ring and the cover member. Pipe fittings.

6. A pipe is connected to the socket of the pipe fitting described in claim 5. Joint structure.

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