Swing joint

Abstract

To provide a swingable joint capable of coping with oscillation of an earthquake or the like while reducing the number of components.SOLUTION: A swingable joint comprises a joint body and a joint pipe connected to the joint body. The joint body includes a water passage hole in a center in a longitudinal direction, and a large diameter part on the inside of a tip side that expands from the side surface of the water passage hole. The joint pipe has a spherical part on the outer surface on the joint body side, a cylindrical part extends from the spherical part, a regulation ring for the spherical part having a negative curved surface part that matches the curvature of the spherical part is provided on the inner periphery while being mounted on the large diameter part, and the spherical part can be swung with respect to the negative curved surface part.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a joint for water pipes and the like, and more particularly to a swing-type joint for absorbing the swinging motion of pipes before and after the joint when the pipes swing relative to each other. [Background technology]

[0002] 2. Description of the Related Art It has been conventionally known that in water piping, a swing-type pipe joint is used to absorb earthquake and other vibrations when connecting pipes with joints. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-249894 A [Patent Document 2] JP 2015-187499 A Summary of the Invention [Problem to be solved by the invention]

[0004] All of these known technologies are called expansion flexible joints, and are configured so that when the joint body and the joint pipe are connected, the joint pipe can expand and contract within a certain range relative to the joint body, and at the same time, can swing within a certain angle range. In addition to allowing the joint body and the joint pipe to swing by the ball joint when vertical vibrations such as an earthquake are applied to the joint, the joint pipe expands and contracts relative to the joint body to absorb stress when a predetermined amount of stress is applied.

[0005] In these known techniques, the joint structure needs to incorporate a configuration for swinging and a configuration for expansion and contraction, which results in a problem of a large number of parts. In addition, the joint structure needs to be integrated into the same location, which results in an overall large size, making it difficult to save space due to the size of the joint.

[0006] Incidentally, in the past, this type of joint had been developed with the idea that it was necessary for the joint body and the joint pipe to swing and expand and contract at the same time in order to absorb vibrations caused by earthquakes and the like, and joints were developed to achieve this. However, in order to achieve both of these, a structure corresponding to each function was required, which resulted in a problem of a large number of parts. In other words, since each of these functions corresponds to a different movement, there are few places where the parts used can be shared.

[0007] On the other hand, earthquake vibrations are those in which P waves arrive first, followed by S waves. P waves themselves are often micro-vibrations, and the subsequent S waves are much larger and have more energy than P waves. However, if the energy is too large, the joint structure cannot absorb the energy even if it uses both sway and expansion, and the joint is destroyed. In other words, even if the sway mechanism and contraction mechanism are applied simultaneously, the joint cannot absorb the stress without breaking in a large earthquake. If that is the case, a configuration that omits the expansion function and uses only the sway function to handle medium-sized earthquakes can reduce the number of parts, rather than the known expansion joints that are structurally complex. The inventor focused on this point and developed a swing joint that can handle sway such as earthquakes by reducing the number of parts. [Means for solving the problem]

[0008] In order to achieve these objects, the swing joint of the present invention is basically composed of a joint body and a joint pipe connected to the joint body. The joint body has a water passage hole in the center of the longitudinal direction and a large diameter part on the inside of the tip side that expands from the side of the water passage hole. The joint pipe has a spherical part on the outer surface of the joint body side and a cylindrical part extended from the spherical part. A spherical part restriction ring is attached to the inner periphery of the large diameter part and has a negative curved surface part that matches the curvature of the spherical part on the inner periphery, and the spherical part can be made to swing relative to the negative curved surface part. In this configuration, a tightening ring is used to connect the joint pipe to the joint body, and a swing joint can be completed with only three parts.

[0009] In addition, the tip of the spherical part is terminated by cutting off the outer arc surface. In this case, the straight pipe does not protrude from the arc shape toward the joint body side as in Patent Document 2, for example, so no extra space is required even when the joint pipe is swung, making it possible to save space.

[0010] Furthermore, for the purpose of watertightness, an O-ring is provided in the space formed by the sphere, the tightening ring, and the expanding portion of the joint body. Conventionally, a number of O-rings were used for watertightness according to the locations where watertightness was required, but in this invention, one O-ring is used to simultaneously stop water at two locations, which contributes to reducing the number of parts. Effect of the Invention

[0011] In the present invention, the above-mentioned means are adopted, so that the joint pipe can be allowed to swing relative to the joint body with a small number of parts. Also, by using only one O-ring, the number of parts can be further reduced. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a perspective view of a swing joint of the present invention; [Diagram 2] Same, disassembled diagram. [Diagram 3]Same, half-cut longitudinal sectional view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the attached drawings. FIG. 1 is a perspective view showing one embodiment of the swing joint of the present invention, and FIG. 2 is a perspective view showing the components constituting the joint in an exploded manner, in which 1 is a joint body with a water passage formed in the longitudinal center, and 2 is a joint pipe, and these two components are basically combined to form the swing joint of the present invention. The joint pipe 2 has a straight cylindrical portion 3 and a spherical portion 4 on the joint body 1 side, and the cylindrical portion 3 and the spherical portion 4 are integrated. In addition, a water passage 5 is provided in the longitudinal center. 6 is an O-ring for watertightness that is sandwiched between the joint body 1 and the joint pipe 2. 7 is a tightening ring for joining the joint pipe 2 to the joint body 1, with its outer thread portion 7a screwed into the large diameter portion 1a formed on the tip side of the expanded portion of the joint body 1, and the inner surface has a negative curved surface portion 7b having a negative curvature that matches the curvature of the spherical portion 4 of the joint pipe 2. Reference numeral 8 denotes a boot made of soft resin for preventing dirt and dust from entering the joint body 1, the joint pipe 2, and the tightening ring 7, etc.

[0014] FIG. 3 is a half-cut cross-sectional view showing the above-mentioned configuration assembled, in which the joint pipe 2 is inserted into the joint body 1, and the tightening ring 7 is screwed into the joint body 1. In this case, when the tightening ring 7 is tightened, the tip of the tightening ring 7 abuts against the butt portion 9 of the joint body 1, and at the same time, the spherical portion 4 of the joint pipe 2 is held in abutment against the inner surface expansion portion 10 of the joint body 1. Since the spherical portion 4 of the joint pipe 2 is supported by two points, the negative curved surface portion 7b of the inner surface of the tightening ring 7 and the inner surface expansion portion 10 of the joint body 1, the joint pipe 2 is allowed to swing relative to the joint body 1. In the structure of this embodiment, the swing angle of the joint pipe 2 is designed to be ±8 degrees, as shown by arrows A and B. If swinging of about ±8 degrees is allowed, it is possible to sufficiently absorb vertical vibrations caused by normal earthquakes. It should be noted that the swing angle of ±8 degrees is the one in this embodiment, and it is possible to design a larger swing angle. In this case, however, the overall structure will be larger, but the basic configuration will be the same as in this embodiment.

[0015] The reason why the spherical portion 4 is supported at two points, the negative curved surface portion 7b of the tightening ring 7 and the inner surface expansion portion 10 of the joint body 1, is to suppress rattling when the joint pipe 2 swings and to perform smooth swinging. However, if the negative curved surface portion 7b alone can reliably support the spherical portion 4, it is possible to omit the support by the inner surface expansion portion 10. In this embodiment, the tightening ring 7 and the large diameter portion 1a are connected by screwing, but what is necessary is that the tightening ring and the large diameter portion are reliably connected and the spherical portion 4 can be accurately positioned, and for example, fitting both of them together is also included in the scope of the present invention. In other words, it is sufficient for the tightening ring 7 to function as a regulating ring for the spherical portion 4. Also, 11 is a step portion formed on the inner joint body side of the joint pipe 2, and when the polyvinyl chloride pipe is directly inserted, the polyvinyl chloride pipe can be reliably attached by inserting it up to this step portion 11. Therefore, other parts such as a polyvinyl chloride socket, which were necessary in the past, are not required.

[0016] In the configuration of this embodiment, there are two locations where fluids such as tap water flowing inside can accidentally leak: the contact surface between the spherical portion 4 of the joint pipe 2 and the tightening ring 7, and the screw-in portion between the large diameter portion 1a of the joint body 1 and the tightening ring 7. Therefore, an O-ring 6 is provided in one location to seal both of these simultaneously. That is, in the swing joint of this embodiment, a single O-ring 6 achieves sealing at two locations. This allows for highly accurate watertightness, while also reducing the number of parts and facilitating parts management.

[0017] The swing joint shown in this embodiment is merely one example, and making the spherical portion 4 larger to further increase the swing angle and further increasing the contact length of the inner expansion portion 10 of the joint body 1 with the spherical portion 4 are part of the design changes and are within the scope of the present invention. [Explanation of symbols]

[0018] 1 Fitting body 2. Pipe Fittings 3. Cylindrical section 4. Sphere section 6 O-ring 7 Tightening ring 9. Butt joint 10. Inner expansion part 11 Step section

Claims

1. A swing joint comprising a joint body and a joint pipe connected to the joint body, The joint body includes: A water vent hole in the longitudinal center; A large diameter portion that expands from a side surface of the water passage hole and is provided on the inside of the tip side; Equipped with The joint pipe is A spherical portion provided on an outer surface of the joint body; A cylindrical portion extending from the spherical portion; a step portion that is tapered and inclined on the inner joint body side inside the spherical portion so that the diameter becomes smaller as the step portion moves away from the cylindrical portion; Equipped with The inner surface of the joint pipe is formed so that a water pipe is inserted through the cylindrical portion to the step portion, The swing joint further includes a regulating ring that is attached to the inner circumferential side of the large diameter portion of the joint body, has a negative curved surface portion on the inner circumferential side that matches the curvature of the spherical portion, and positions the spherical portion; A swing joint, characterized in that the spherical portion is capable of swinging relative to the negative curved surface portion.

2. 2. A swing joint according to claim 1, wherein at least a portion of said step is provided on a side farther away from said cylindrical portion than said restraining ring.

3. 3. A swing joint as claimed in claim 1 or 2, wherein an O-ring is provided in the space formed by the spherical portion, the regulating ring and the expansion portion of the joint body, and at least a portion of the step portion is provided inside the O-ring.

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