JP2005273808A - Pipe fitting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pipe fitting capable of shrinking the diameter of a split ring uniformly even with a small tightening force to result in a high connecting reliability and applicable favorably to service water piping etc. using synthetic resin pipes of polyethylene etc. <P>SOLUTION: The split ring furnished at the ends with flanges is mounted on the outside of a connection part to be inserted into a pipe to be connected, and bolt holes are formed in the flanges of the split ring, and the flange contacting part of each bolt inserted into the hole, the flange contacting part of a nut to receive the bolt, or the flange contacting part of a washer set between the bolt or nut and the flange is formed in a convex spherical shape, while the flange portion where the bolt, nut, or washer contacts is shaped recessing so as to receive the convex spherical shape, and the pipe to be connected is inserted between the connection part and the split ring, and the bolt and nut are tightened so that the diameter of the split ring is shrunk. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a joint for connecting pipes, and more specifically, a joint with improved joint reliability at a pipe joint, which is preferably used for water supply pipes using synthetic resin pipes such as crosslinked polyethylene. It relates to a joint that can be made.

  One of the joints connecting the synthetic resin pipes is fitted with a split ring with a convex strip provided on the inner peripheral surface along the circumferential direction on the outer peripheral surface of the connecting portion. Thus, there is a pipe joint provided with a tightening ring in which both end portions are flange portions and the flange portions are tightened with bolts so that the split ring is tightly coupled to the outer surface of the tube.

  For example, “..., The first connection part 41 for fitting the end part of the forward pipe 2, the second connection part 42 for fitting the end part of the return pipe 3, and the end part of the connection pipe 9 A third connection part 43 to be fitted is provided, the first connection part 41 and the second connection part 42 are provided in parallel in the same direction, and the third connection part 43 is provided in the first connection. The third connecting portion 43 is provided coaxially with the second connecting portion 42, and the second connecting portion 42 is provided so as to be opposite to the first connecting portion 41 and the second connecting portion 42. The first connecting portion 41 and the third connecting portion 43 are smaller in diameter than the first connecting portion 41 and the third connecting portion 43. Further, stoppers 411 and 421 are formed on the outer periphery of the first connecting portion 41 and the second connecting portion 42. The end position of the forward pipe 2 or the return pipe 3 to be fitted to the first and second connection portions 41 and 42 can be determined. In addition, saw blade-like protrusions 412 and 422 are provided at positions closer to the tip side than the stoppers 411 and 421 on the outer periphery of the first connection portion 41 and the second connection portion 42. In addition, it is possible to prevent the forward pipe 2 or the return pipe 3 fitted to the connection portions 41 and 42 from coming off.The saw blade-shaped protrusions 412 and 422 are provided in the first and second shapes. Several rows are provided at intervals in the axial direction of the two connection portions 41 and 42. A thread 431 is formed on the outer periphery of the third connection portion 43, and the connection pipe 9 is fixed by screwing. Pipe joints are known "(see, for example, Patent Document 1).

This pipe joint is a pipe joint that can connect two pipes in parallel, but the connection structure of each pipe is provided on the inner peripheral surface of the split ring by reducing the diameter of the split ring by tightening a bolt. The protruding line is pressed against a connected pipe such as a cross-linked polyethylene pipe inserted into the connecting portion, and the split ring and the polyethylene pipe are tightly coupled to exhibit a resistance to disconnection and a sealing performance. According to this pipe joint, since the cross-linked polyethylene pipe is permanently pressed against the connecting portion, high joint reliability can be realized.
JP-A-6-42686, paragraph number 0013, FIG. 1, FIG.

  However, in the conventional split ring, when the joint diameter increases, the split width also increases. Therefore, when the bolt 3 is set so as to be perpendicular to one flange portion 212 of the split ring 2 as shown in FIG. Since the bolt 3 is fastened to the nut 4 because it is not perpendicular to the other flange portion 211, no force is applied evenly to the reduced diameter ring portion 22 of the split ring 2, and the connected pipe is a perfect circle. In other words, the diameter could not be reduced, and high connection reliability could not be obtained. Further, in order to increase the reliability, the tightening force has to be increased, and there is also a problem that reliable reliability cannot be obtained.

  Further, some conventional split rings have a shape as shown in FIG. In this case, the inner peripheral surface of the reduced-diameter ring portion 22 is substantially the same as the outer diameter of the connected pipe and is slightly larger, and the flange portions 211 and 212 and the bolt surface are parallel to each other. Therefore, although the above problems do not occur, there is a problem that the diameter reducing force is not so much applied to the diameter reducing ring portion 22.

  The present invention has been made for the purpose of providing a joint that can be uniformly reduced in diameter even if the tightening force is small, has high connection reliability, and is suitably used for water supply pipes using synthetic resin pipes such as polyethylene. It is a thing.

  The pipe joint according to claim 1 of the present invention for solving the above problems (invention 1) is provided with a split ring having flanges at both ends on the outside of a connection part to be inserted into a connected pipe, Bolt hole is provided in the flange of the split ring, and the flange contact surface of the bolt inserted through the bolt hole, the flange contact surface of the nut receiving the bolt, or the washer mounted between the bolt or the nut and the flange. The flange contact surface is a convex spherical shape, and a concave shape that receives the convex spherical shape is provided on the flange contacted by the bolt, nut, or washer, and the pipe to be connected is connected between the connection portion and the split ring. And the split ring is reduced in diameter by tightening the bolt and nut.

  The pipe joint according to claim 2 (invention 2) is provided with a split ring having both ends as flanges and a tightening ring having both ends as flanges on the outside of the connection portion to be inserted into the connected pipe. A bolt hole is provided in the flange part of the tightening ring, and the flange contact surface of the bolt inserted into the bolt hole, or the flange contact surface of the nut receiving the bolt, or between the bolt or the nut and the flange part. The flange contact surface of the washer to be mounted has a convex spherical shape, and a concave shape that receives the above convex shape is provided on the flange that the bolt, nut, or washer contacts, and the pipe to be connected is split with the connection portion. And the bolt and nut are tightened to reduce the diameter of the tightening ring to reduce the diameter of the split ring.

  The pipe joint of invention 1 or invention 2 may be made of metal or plastic, but when the pipe to be connected is made of metal, a metal pipe joint is used, and in the case of a synthetic resin pipe It is preferable to use a resin pipe joint. In addition, when the pipe to be connected is a synthetic resin pipe, a hard vinyl chloride resin pipe, a polyethylene pipe, a cross-linked polyethylene pipe, a polybden pipe, a double-layered pipe of polyethylene and cross-linked polyethylene, a polyphenylene sulfide pipe, etc. are used. be able to. The synthetic resin pipe may be a composite pipe reinforced with a metal material such as aluminum.

  The pipe joint according to the first aspect of the present invention receives a split ring provided concentrically outside the connecting portion to be inserted into the pipe to be connected and having both end portions as flanges, and a bolt inserted through a through hole in the flange portion and the bolt. It consists of a nut and a packing that is attached to a joint connection portion to which a connected pipe is connected. A washer may be used between the bolt or nut and the flange.

  The flange contact surface of the bolt head, the flange contact surface of the nut, or the flange contact surface of the washer has a convex spherical shape, and the through hole of the flange has a concave shape in which the convex shape can move. ing. In a state before the bolt and the nut are tightened, the bolt is inserted into the through hole obliquely and screwed into the nut. When the bolt is tightened into the nut, the bolt and the collar, or the nut and the collar, or the washer and the collar are in a state where the convex spherical shape is in contact with the collar, and slides on the concave contact surface. Is possible.

  The convex spherical shape needs to be fitted into the concave shape and slid on its contact surface and screwed without rattling when the bolt is tightened. Therefore, the radius of the convex spherical shape is preferably the same as the radius of the concave shape, but may be slightly smaller as long as the convex spherical shape can smoothly slide on the concave spherical surface.

  When the bolt and the nut are tightened through the washer or without the washer, the convex spherical shape of the bolt, nut, or washer slides along the concave spherical surface of the collar. Therefore, at any stage of the tightening operation, the bolt and the nut are not twisted and are tightly coupled.

  In addition to the contact between the nut and the flange in a spherical shape, if the bolt and the flange contact surface are in a spherical shape, the bolt and the nut may be twisted at any stage of the tightening operation. Since it slides smoothly, the bolts are tightened smoothly and connection reliability is increased. In addition, only the contact surface between the bolt head side and the buttock side, or only the contact surface between the nut side and the buttock side, or the contact surface between the bolt head side and the buttock side, and the contact surface between the nut and the buttock side Both may be a convex spherical shape or a kamaboko-shaped convex shape.

  That is, when the pipe to be connected is inserted outside the joint connection part, the bolt, the nut and, if necessary, the washer are attached to the collar part, and the bolt is tightened, the split ring is reduced in diameter. The angle formed by the bolt shaft that passes through and the normal direction of the collar surface gradually decreases. At that time, the angle of the bolt shaft is changed so as to be the same angle as the flange surface, but the nut sequentially changes the angle in accordance with the angle, and finally the flange portions are brought into proximity or contact with each other. At this time, since the flange portion receives a force that is bent in the center direction of the split ring, a sufficient diameter reducing force is generated in the diameter reducing ring portion of the split ring, and a uniform diameter reducing force is generated over the entire circumference.

  Due to the diameter-reducing force generated in this way, the protrusions provided in the circumferential direction on the inner peripheral surface of the diameter-reducing ring portion of the split ring reduce the diameter of the connected pipe and press it against the recesses of the joint body connecting portion. As a result, a pull-out resistance is generated. At this time, it is desirable that the recess is provided concentrically with the projection of the split ring. In addition, the protrusions provided concentrically with the packing groove in which the packing is accommodated brings the pipe to be connected into close contact with the packing, and exhibits sealing performance.

  It is desirable that the nut or the washer have a shape having an anti-rotation function, for example, a corner portion is provided so as not to rotate in a direction perpendicular to the shaft so as not to rotate when the bolt is tightened. For example, it is preferable that the both side portions have a convex spherical shape with a plane cut out. Or, it may be a convex spherical shape, for example, a semi-cylindrical convex shape with an arcuate back side, and in either case, the heel side is a concave groove shape that receives the convex shape with both sides cut off by a flat surface. Good to be.

  When both sides are cut off by a flat surface, in any of the above convex shapes, if the distance between the straight lines formed by the cutting planes on both sides and the spherical surface is smaller than that on the chord side, the nut is dropped directly into the groove. If it is large, one end of the nut can be applied to one end of the groove, and the nut can be fitted into the groove while turning. Therefore, both sides of the kamaboko-shaped convex shape do not necessarily have to be parallel.

  In addition, when the collar contact surface of the washer has a convex spherical shape, the same effect can be obtained by screwing them using a normal bolt or nut having a flat contact surface. It may be made like.

  Furthermore, in addition to the bolt head side and the flange being in contact with each other in a spherical shape, if the nut side and the flange are in contact with each other in a spherical shape, the bolt and nut are Therefore, the bolts are tightened smoothly and connection reliability is increased. Note that only the contact surface between the bolt head side and the flange portion is a spherical shape, or only the contact surface between the nut side and the flange portion is a semi-cylindrical shape surface, or the contact surface between the bolt head side and the flange portion is The contact surface between the nut side and the flange portion may be a spherical shape surface.

  The pipe joint of the invention 2 includes a split ring provided concentrically outside the connecting portion to be inserted into the pipe to be connected, a clamping ring provided on the outside of the split ring and having both ends as flanges, It consists of a bolt inserted into the through hole, a nut that receives the bolt, and a packing that is attached to a joint connecting portion to which a connected pipe is connected. A washer may be used between the bolt or nut and the flange.

  Bolt hole is provided in the collar part of the tightening ring, and the collar contact surface of the bolt inserted through the bolt hole, the collar contact surface of the nut receiving the bolt, or the washer mounted between the bolt or the nut and the collar part The flange contact surface is formed into a convex spherical shape, and a concave shape that receives the convex shape is provided on the flange contacted with the bolt, the nut, or the washer.

  In the invention 2, the bolts attached to the flanges of the fastening ring provided on the outer side of the split ring and having both end portions as the flanges are tightened to reduce the diameter of the tightening ring. The connected pipe is compressed by reducing the diameter, and anti-separation performance and sealing performance are exhibited. Since the configuration of the flange portion and the nut in the tightening ring is the configuration of the flange portion and the bolt, nut, or washer in the split ring of the pipe joint of the first aspect, it will not be described again.

  In this case as well, as in the case of the invention 1, it goes without saying that a convex spherical washer and a bolt or nut having a flat collar contact surface may be used.

  Of course, even in this case, it is possible to use a washer having a convex spherical shape under the head of the bolt, and attach and tighten the concave spherical shape of the collar, and it is also possible to use the above washer under the nut. Not too long.

  In the pipe joint of aspect 1, when the bolt is tightened, the contact surface between the nut and the flange slides along the arc shape of the groove. Therefore, at any stage of the tightening operation, the nut is not twisted with the flange portion and is tightened smoothly, so that the tightening force is small and the connection reliability is increased.

  In the invention 2, since the split ring is compressed by the tightening ring that is tightened smoothly, the split ring uniformly tightens the connected pipe over the entire circumference, and the connection reliability is further increased.

  In the invention 3, in addition to the contact surface between the nut and the flange portion, the contact portion between the bolt head and the flange portion has a convex spherical shape. Therefore, when the bolt is tightened, the nut is more and more smoothly screwed. Connection reliability increases.

  Next, the present invention will be described with reference to the drawings. FIG. 1 is an example of a pipe joint having a split ring in which both end portions are flange portions and the contact surface between the nut and the flange portion is a convex spherical shape, (a) is a half sectional view, and (b) is a state before tightening. The horizontal sectional view which shows the state of this, (c) is a horizontal sectional view which shows the state after clamping | tightening. FIG. 2 is a half cross-sectional view of an example of a pipe joint in which a split ring is fitted with a tightening ring in which both end portions are flange portions and a contact surface between the nut and the flange portion is a convex spherical shape. FIG. 3 is a partially enlarged view of an example of the bolt and nut screwing, (a) is a cross-sectional view of the only contact surface between the nut and the flange portion, and is a cross-sectional view of the bolt head, and (b) is a bolt head and Sectional view of the convex spherical surface only of the contact surface with the flange, (c) is a convex spherical surface of the contact surface between the bolt head and the flange, and the contact surface between the nut and the flange is a semi-cylindrical convex shape. It is sectional drawing of what was taken as.

  In FIG. 1, protrusions 221 are provided along the circumferential direction on the inner peripheral surface of the reduced diameter ring portion 22 on the outer peripheral surface of the connecting portion 7 of the pipe joint 1, and the facing flange portions 211 and 212 are tightened together. The split ring 2 is attached to the outer surface of the connected pipe 6.

  A bolt hole 23 is provided in the flange portions 211 and 212 of the split ring 2, and the flange contact surface 41 of the nut 4 that receives the bolt 3 inserted through the bolt hole 23 has a convex spherical shape. The abutting flange 211 has a concave groove shape that matches the convex shape. The convex spherical shape is a shape in which both sides thereof are cut out by a plane (kamaboko-shaped convex shape) to prevent follow-up, and the concave groove is also a shape corresponding thereto.

  The connected pipe 6 is inserted between the connecting portion 7 and the split ring 2, and the split ring 2 is fastened by the bolt 3 and the nut 4 to be fastened to the connected pipe 6. At this time, the shaft of the bolt 3 is inclined obliquely before tightening, but as the bolt 3 is tightened into the nut 4, the nut 4 slides on the arc surface of the concave groove of the flange portion 221 and is smooth without being twisted. The flanges 211 and 212 come close to or come into contact with each other, and the protrusion 221 provided on the inner peripheral surface of the reduced diameter ring portion 22 of the split ring 2 tightens the outer surface of the connected pipe 6.

  In FIG. 2, the split ring 2 is provided on the outer peripheral surface of the connecting portion 7 of the pipe joint 1. The split ring 2 is provided on the inner peripheral surface of the reduced diameter ring portion 22 along the circumferential direction. 2 is provided with tightening rings 5 having both end portions as flange portions 511 and 512 and tightening the flange portions 511 and 512 to tightly connect the split ring 2 to the outer surface of the connected pipe 6.

  Bolt holes 52 are provided in the flange portions 511 and 512 of the tightening ring 5, and the flange contact surface 41 of the nut 4 that receives the bolt 3 inserted through the bolt hole 52 is formed into a convex spherical shape, and the nut 4 comes into contact therewith. The flange portion 511 has a concave groove shape that matches the convex spherical shape. The convex spherical shape is a shape in which both sides thereof are cut out by a plane (kamaboko-shaped convex shape) to prevent follow-up, and the concave groove is also a shape corresponding thereto.

  The pipe 6 to be connected is inserted between the connecting portion 7 and the split ring 2, and the tightening ring 5 provided outside the split ring 2 is fastened by the bolt 3 and the nut 4 to reduce the reduced diameter ring portion of the split ring 2. The diameter 22 is reduced and is tightly connected to the connected pipe 6. At this time, the shaft of the bolt 3 is inclined obliquely before tightening, but as the bolt 3 is tightened into the nut 4, the nut 4 slides on the arc surface of the concave groove of the flange portion 511 and is smooth without being twisted. The flanges 511 and 512 come close to each other or come into contact with each other, and the protrusion 221 provided on the inner peripheral surface of the reduced diameter ring portion 22 of the split ring 2 tightens the outer surface of the connected pipe 6.

  The shape of the surface where the nut 4 contacts the flange is a convex spherical shape. However, as shown in FIG. 3 (a), even if only the contact surface between the nut and the collar has a convex spherical shape (in this example, a kamaboko-shaped convex shape), it is shown in FIG. 3 (b). As shown in FIG. 3 (c), even if the contact surface between the bolt head and the collar is convex, the contact surface between the bolt head and the collar is convex. It may be a spherical shape, and the contact surface between the nut and the flange may be a semi-cylindrical convex shape.

  In either case, even if the axis of the bolt 3 is tilted before tightening, the bolt shaft becomes straight as it is tightened. Therefore, the bolt shaft tightens the bolt 3 and the nut 4 to fasten the split ring 2 to the connected pipe 6. Alternatively, the diameter of the tightening ring 5 may be reduced and the split ring 2 may be tightly connected to the connected pipe 6.

  In addition, when using a washer with a contact surface with the collar having a convex spherical shape or a kamaboko-shaped convex shape and using a bolt or nut whose contact surface with the washer is a flat plate shape, the convex spherical shape or the kamaboko-shaped convex shape is used. The nuts and bolts having a shape are only divided into two parts, that is, a washer part, and the actions and effects are exactly the same.

  Since the tightening force can be reduced by using the present invention, the pipe and the joint can be easily connected even in a site where workability is deteriorated due to upward work such as ceiling piping. Suitable for cold and hot water piping such as piping.

It is an example of a pipe joint having a split ring in which both end portions are flange portions and the contact surface between the nut and the flange portion is a convex spherical shape, (a) is a half sectional view, and (b) is a state before tightening. The horizontal sectional view shown, (c) is a horizontal sectional view showing the state after tightening. FIG. 5 is a half cross-sectional view of an example of a pipe joint in which a split ring is fitted with a tightening ring having both end portions as flanges and a contact surface between a nut and a flange as a convex spherical shape. It is the elements on larger scale of an example of the screwing of a volt | bolt and a nut, (a) is sectional drawing of what made only the contact surface of a nut and a collar part into a semi-cylindrical shape, (b) is a bolt head and ridge part. (C) is a sectional view of the contact surface between the bolt head and the flange, and the contact surface between the nut and the flange is a semi-cylindrical protrusion. FIG. It is an example of the conventional split ring. It is another example of the conventional split ring.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pipe joint 2 Split ring 211,212 Split ring flange 22 Reduced diameter ring part 221 Convex strip 23 Bolt hole 3 Bolt 31 Bolt flange contact surface 4 Nut 41 Nut flange contact surface 5 Tightening ring 511, 512 Tightening Ring flange 52 Bolt hole 6 Connected pipe 7 Outside connection

Claims (2)

  A split ring with hooks at both ends is attached to the outside of the connecting part to be inserted into the pipe to be connected, a bolt hole is provided in the hook part of the split ring, and a bolt hook contact inserted through the bolt hole The surface, the flange contact surface of the nut that receives the bolt, or the flange contact surface of the washer mounted between the bolt or the nut and the flange has a convex spherical shape, and the bolt, nut, or washer contacts A pipe joint characterized in that the part has a concave shape that receives the convex spherical shape, the pipe to be connected is inserted between the connection part and the split ring, and the bolt and nut are tightened to reduce the diameter of the split ring. . A split ring having both ends as flanges and a tightening ring having both ends as flanges are provided on the outside of the connection portion to be inserted into the pipe to be connected. Bolt holes are formed in the flanges of the tightening ring. The buttock contact surface of the bolt that is provided and inserted through the bolt hole, the buttock contact surface of the nut that receives the bolt, or the buttock contact surface of the washer mounted between the bolt or the nut and the buttock is a convex spherical shape. The flange that the bolt, nut, or washer contacts is a concave shape that receives the convex spherical shape, and the connected pipe is inserted between the connection portion and the split ring, and the bolt and nut are tightened. A pipe joint characterized in that the diameter of the split ring is reduced by reducing the diameter of the fastening ring.

Images