JPH01145489A - Pipe joint - Google Patents

Abstract

PURPOSE: To always perceive most preferable final fastening joint by providing a connecting member having a projection intruding into each facing surface of a cap nut and a flange section at screwing a cap nut into a cylinder section. CONSTITUTION: A joint has a joint main body 8 and a cap nut 2, the joint main body 8 comprising a joint body 3 and a slit ring 1. A plurality of projections 19a, 19b of which tips are sharp is respectively provided on both side surfaces of a washer 17 as a connecting member inserted outside to a cylinder section 14 of the slit ring 1. When the cap nut 2 is rotated, the washer 17 is pushed to a flange 10 of the slit ring 1, tips of the both projections 19a, 19b of the washer 17 are contacted to a tip surface 2a of the cap nut 10 to intrude thereto, so fastening torque of the cap nut 2 is rapidly increased.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a pipe joint for connecting connecting pipes constituting water supply pipes, hot water supply pipes, etc. When connecting pipes, by tightening them,
This invention relates to a pipe joint with no risk of the threaded portion being damaged or deformed.

(Prior Art) Connecting pipes constituting water supply channels and hot water supply channels need to be connected so that they do not easily come off and do not leak water from the joints. When connecting connecting pipes, for example, as disclosed in Japanese Utility Model Application Publication No. 61-22991, a method of connecting the ends of each connecting pipe with each other by screwing through a pipe joint is relatively simple. It is often used because it provides a strong fastening force.

This connection structure will be explained based on FIG. 5.

The pipe joint includes a pipe joint main body 50 and a cap nut 44 that is screwed onto the pipe joint main body 5o, and the pipe joint main body 5° includes a joint body 40 and a slit ring that is externally fitted onto the joint body 40. 5
It is composed of 1. Then, the end of the connecting pipe 5 is inserted between the joint body 40 and the slit ring 51, and in this state, the cap nut 44 is screwed onto the outside of the slit ring 51, thereby connecting the connecting pipe 5 to the joint body 40. It is designed to be connected to the slit ring 51 by being sandwiched therebetween.

To explain in detail the structure of each member, the joint body 4
0 is a cylindrical guide portion 42 into which the end of the connecting pipe 5 is inserted.
and a nut portion 41 integrally extending from this guide portion 42.
and a connecting portion 47. A packing 43 is attached to the outer periphery of the tip of the guide portion 42.

The slit ring 51 has a hexagonal cylindrical collar portion 60 that is fitted onto the nut portion 41 of the joint body 40, and a cylindrical portion 54 into which the end of the connecting tube 5 is inserted. The cylindrical part 5
A male threaded portion 52 is formed on the outer periphery of 4, and a cylindrical portion 54
A notch groove 5 is provided at the tip of the tip so that the diameter of the tip can be reduced inward.
3 is formed. The cap nut 44 has a female threaded portion 45 that is screwed into the male threaded portion 52 of the slit ring 51, and a tapered portion 46 provided on the inner periphery of the rear end of the female threaded portion 45.

When connecting a pair of connecting pipes 4.5, such as a hot water supply pipe or a water supply pipe, using the pipe joint configured as described above, as shown in FIG. At the same time, the female screw portion 45 of the cap nut 44 is screwed into the male screw portion 52 of the slit ring 51. Then, one of the connecting pipes 4 is screwed and connected to the connecting part 47 of the joint body 40, and the guide part 4 of the joint body 40
2 and the cylindrical portion 54 of the slit ring 51 .

In this state, the end surface of the cap nut 44 is connected to the slit ring 51.
Tighten the cap nut 44 using a tool such as a spanner until it substantially contacts the side end surface of the flange 60. As the cap nut 44 moves toward the flange 60 of the slit ring 51, the tapered portion 46 of the cap nut 44 presses the tip of the cylindrical portion 54 of the slit ring 51 inward, and this cylindrical portion 5
By reducing the diameter of the tip 4, the outer surface of the connecting tube 5 is pressed over the entire circumference, and the connecting tube 5 is brought into pressure contact with the outer surface of the packing 43.

2, by elastically pressing the inner peripheral surface of the connecting pipe 5 against the packing 43 and sandwiching the connecting pipe 5 between the joint body 40 and the slit ring 51, good sealing performance and strong sealing properties can be achieved. The connecting pipe 5 can be connected to the pipe joint, and liquid can be reliably prevented from leaking from this connecting part.

(Problems to be Solved by the Invention) However, piping such as hot water supply pipes is usually carried out in narrow and dark places such as in the ceiling or under the floor. For this reason, bag nut 44
When rotating the cap nut 44 relative to the slit ring 51 to bring the tip end surface of the cap nut 44 into contact with the side end surface of the flange 60, it often happens that it is not possible to visually confirm that the end surfaces have butted against each other. .

Conventionally, in such a case, the cap nut 44 is carefully tightened gradually, and after the tip end surface of the cap nut 44 comes into contact with the side end surface of the flange 60 of the slit ring 51, the tightening is performed using a torque. The increase in torque is detected manually through the tool, and the tightening is stopped when it becomes difficult to tighten.However, the tightening torque applied to the tool increases gradually and continuously, so it is difficult to tighten properly. The final tightening time was not known, and the cap nut 44 was sometimes further tightened even though the tip end surface of the cap nut 44 was in contact with the side end surface of the flange 60.

When the cap nut 44 is further tightened with the tip end surface of the cap nut 44 in contact with the side end surface of the flange 60, the female threaded portion 45 of the cap nut 44 and the male threaded portion 52 of the slit ring 51 are connected in the axial direction. This strong force acts on these threaded parts and causes them to become damaged and deformed. When the threaded portion is damaged or deformed in this way, the cap nut 44 retreats from the predetermined tightening position, and the force with which the cap nut 44 tightens the connecting pipe 5 decreases, causing the diameter of the packing 43 to decrease. The pressure drops,
Water leakage could occur.

When the connecting tube 5 is made of a synthetic resin material with excellent corrosion resistance and productivity, the strength of the threaded portion of the connecting tube 5 is relatively small, so the cap nut 44 is tightened with a specified torque. The disadvantage was that even if the tightening was a little stronger than the torque, the threaded part would be crushed.

On the other hand, it is also conceivable to increase the strength of the threaded portions, for example by increasing the threads of the female threaded portion 45 of the cap nut 44 and the male threaded portion 52 of the slit ring 51, or by lengthening the threaded joint portion. However, when formed in this way, there is a drawback that the diameter and length of the pipe joint increase, which is disadvantageous in terms of cost, and it is not suitable when connecting the connecting pipes 4.5 in a narrow place.

The present invention solves the above-mentioned drawbacks, and its purpose is to be able to always detect the optimal final tightening point even when connecting pipes where the connection point cannot be seen, and to prevent damage to the threaded part. An object of the present invention is to provide a pipe joint that can obtain reliable sealing performance by preventing deformation and deformation. Still another object of the present invention is to provide a pipe joint in which productivity can be improved by making the pipe joint body and the cap nut from synthetic resin materials, and reliable sealing performance can be obtained without increasing the size of the pipe joint body. Our goal is to provide the following.

(Means for Solving the Problems) The pipe joint of the present invention includes a cylindrical part that has a male thread formed on the outer periphery, is inserted into the end of the connecting pipe, and a proximal end of the cylindrical part that protrudes toward the outer periphery. A pipe joint body made of synthetic resin is provided with a flange, and a female thread part is formed on the inner periphery of the tip part to be screwed into the male thread part of the pipe joint body, and a threaded part for threading the two is formed on the inner periphery of the base part. a synthetic resin cap nut provided with a tapered part that can sometimes reduce the diameter of the tip of the cylindrical part, and a cap nut disposed outside the cylindrical part of the pipe joint body between the collar part of the pipe joint body and the cap nut. and a fastening member having a projection that bites into each opposing surface of the cap nut and the flange when the cap nut and the cylindrical portion are screwed together, thereby achieving the above object.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, the pipe joint of the present invention includes:
The pipe joint body 8 has a pipe joint body 8 and a cap nut 2, and the pipe joint body 8 includes a joint body 3 and a slit ring 1 fitted onto the joint body 3.
It is composed of. Then, by inserting the end of the connecting pipe 5 between the joint body 3 and the slit ring l, and screwing the cap nut 2 onto the slit ring 1 in this state, the connection between the joint body 3 and the slit ring 1 is The ends of the connecting tubes 5 are clamped and connected, and another connecting tube 4 is connected to the other end of the joint body 3.

The joint body 3 is formed into a substantially cylindrical shape using a synthetic resin material having excellent heat resistance such as glass fiber reinforced heat resistant resin. One end of the joint body 3 is a connecting part 30 connected to the connecting pipe 4 as described above, and the other end of the joint body 3 is a cylindrical guide part 31.

A square, for example hexagonal, nut portion 32 is provided approximately at the center of the joint body 3, and a connecting portion 30 and a guide portion 31 extend from the nut portion 32, respectively. An annular groove 33 is formed on the outer periphery of the end of the guide portion 31 on the side where the connecting tube 5 is inserted, and the packing 6 is mounted in the annular groove 33.

The slit ring 1, like the joint body 3, is made of a synthetic resin material with excellent heat resistance and is formed into a cylindrical shape. This slit ring 1 has a cylindrical portion 1 with a male threaded portion 15 formed on the outer periphery.
4, and a flange lO whose outer surface is hexagonal and integrally protrudes from one end of the cylindrical portion 14 toward the outer circumference. A plurality of notch grooves 16 long in the axial direction are provided at the tip of the cylindrical portion 14.
is formed, and the tip of this cylindrical portion 14 is configured to be able to contract inward by a pressing force from the outside. The inner diameter of the cylindrical portion 14 is approximately equal to or slightly larger than the outer diameter of the connecting pipe 5. The length of the cylindrical portion 14 is set so that the tip of the notched groove 16 substantially corresponds to the position of the annular groove 33 provided on the outer periphery of the guide portion 31 of the joint body 3. The open side surface of the flange portion 10 is formed into a shape that can be fitted onto the nut portion 32 of the joint body 3. Further, the outer surface of the collar portion 10 has a tapered surface I2 that is inclined inward on the cylindrical portion 14 side. Flange portion 10 of the slit ring 1
is fitted onto the nut portion 32 of the joint body 3, the cylindrical portion 14 of the slit ring 1 is arranged concentrically around the guide portion 31 of the joint body 3, and the outer surface of the guide portion 31 and the inner surface of the cylindrical portion 14 are arranged concentrically. A gap 7 is formed between the two and into which the connecting pipe 5 can be inserted.

The cap nut 2, which is screwed into the cylindrical portion 14 of the slit ring 1, is formed into a substantially cylindrical shape from a synthetic resin material with excellent heat resistance, similar to the slit ring 1 and the joint body 3.

The outer surface of the front end of the cap nut 2 has a substantially circular shape with unevenness formed on the outer periphery, and the rear outer surface of the cap nut 2 has a hexagonal shape. A female screw portion 20 is formed on the inner periphery of the tip of the cap nut 2 and is screwed into the male screw portion 15 on the outer periphery of the cylindrical portion 14, and a tapered portion whose diameter decreases toward the rear end is formed on the inner periphery of the approximately central portion of the cap nut 2. 21 is formed, and an opening 24 whose inner diameter is slightly larger than the outer diameter of the connecting pipe 5 is further formed on the rear end side.

A washer 17 as a fastening member that is inserted into the cylindrical portion 14 of the slit ring 1 between the collar portion 10 of the slit ring 1 and the cap nut 2 is shown in FIGS. 3(a) and 3(b).
As shown in the figure, it is made of a thin ring-shaped metal material. As the material for the washer 17, a material that is hard and has excellent corrosion resistance, such as stainless steel, can be used. The inner diameter of the washer 17 is formed to be slightly larger than the outer diameter of the flange 10 of the slit ring 1, and is movably inserted into the cylindrical portion 14. A plurality of projections 19a and 19b each having a sharp tip are provided on both sides of the washer 17 at appropriate intervals. Each protrusion 19a and 19b is formed by punching out a part of the washer body 17a, - the protrusion 19a on the side is formed by punching out a part of the washer body 17a on one side, and the protrusion on the other side is formed by punching out a part of the washer body 17a. 19b is formed by punching out a part of the washer body 17a to the other side. Each protrusion 19a, 1
The direction in which the washer 9b is ejected is such that the washer 17 is placed between the flange 10 of the slit ring 1 and the cap nut 2.
7 is extrapolated onto the cylindrical portion 14 of the slit ring 1,
The tips of the protrusions 19a and 19b are oriented in a direction where they can easily bite into the tip surface 2a of the cap nut 2 and the side end surface 10a of the flange 10 as the cap nut 2 rotates, that is, as shown in FIG. The protrusion 19a' of the protrusion 19a on one side provided on the side surface of the washer 17 is formed to face the rotating direction (direction of the arrow) of the cap nut 2, and the protrusion 19a' of the protrusion 19 on the other side 19b' is in the opposite direction to the direction in which the protrusion 19 is projected. The outer diameter of the washer 17 is approximately equal to the outer diameter of the cap nut 2 and the alligator portion 10 of the slit ring 1.

A case will be described in which a pair of connecting pipes 4.5, such as a hot water supply pipe and a water supply pipe, are connected using the pipe joint having the above configuration.

As shown in FIG. 2, a joint body 3 is attached to the end of one connecting pipe 4.
At the same time, the flange IO of the slit ring 1 is fitted onto the nut 32 of the joint body 3, and the washer 17 is fitted onto the cylindrical portion 14 of the slit ring 1. A cap nut 2 is loosely screwed into the cylindrical part 14 of the first part. Then, the opening 24 of the bag nut 2
Insert the connecting pipe 5 from the cylindrical part 14 of the slit ring l and the guide part 32 of the joint body 3.
Insert it into the deep part of the gap 7 formed between. Then, with the flange 10 of the slit ring 1 fixed with a tool or the like, turn the cap nut 2 with the tool or the like to tighten the cap nut 2.
The female threaded portion 20 of the cylindrical portion 14 is screwed into the male threaded portion 15 of the cylindrical portion 14. This screwing of the cap nut 2 causes the cap nut 2 to move toward the flange 10 of the slit ring 1. Tip surface 2 of bag nut 2
When a approaches the side end surface 10a of the flange 10 of the slit ring 1, the tapered portion 21 of the cap nut 2 presses inward the tip of the cylindrical portion 14 where the notch groove 16 is formed. As a result, the diameter of the tip of the cylindrical portion 14 is reduced and the connecting pipe 5
is pressed inward, and the inner surface of the connecting tube 5 comes into pressure contact with the outer surface of the packing 6, creating an airtight seal at this portion and preventing the connecting tube 5 from separating from the pipe joint.

Also, by rotating the bag nut 2 in this way, the bag nut 2
The tip end surface 2a is the side end surface 1 of the collar portion 10 of the slit ring l.
When approaching 0a, washer 1 is moved due to the movement of cap nut 2.
7 is pushed toward the flange 10 side of the slit ring L, and the ends of both protrusions 19a and 19b of the washer I7 are pushed into the cap nut 2.
The tip end surface 2a of the flange 10 comes into contact with the side end surface 10a of the collar portion 10. When the cap nut 2 is rotated from this state, as shown in FIG.
Each protrusion 19a and 1 of the washer 17 is attached to the side end surface 10a of the washer 17.
Since the ends of the cap nuts 9b bite into each other, the tightening torque of the cap nut 2 suddenly increases. When further force is applied to the tool to tighten the cap nut 2, the cap nut 2 approaches the flange 10 side and the protrusions 19a and 19b of the washer I7 further bite into the cap nut 2 and the flange 10, so that the cap nut 2 is tightened. Tightening in step 2 further increases the torque. When both end surfaces of the washer 17 come into contact with the tip end surface 2a of the cap nut 2 and the side end surface 10a of the flange 10, the tightening torque of the cap nut 2 increases to such an extent that it becomes difficult to rotate it. Therefore, the operator senses the increase in torque and stops tightening the cap nut 2 at this point. In this way, the tip surface 22 of the cap nut 2
is set so that appropriate sealing performance between the connecting pipe 5 and the pipe joint can be obtained in a state in which the connecting pipe 5 and the pipe joint are in contact with the side end surface 10a of the flange 10 of the slit ring 1 via the washer 17.

Further, as described above, in a state where both side surfaces of the washer 17 are almost in contact with the tip end surface 2a of the cap nut 2 and the side end surface 10a of the flange 10, the torque increases when tightening the cap nut 2; The torque is mainly applied to each protrusion 19a, 1
The tip of 9b bites into the tip surface 2a of the cap nut 2 and the side end surface 10a of the flange 10, and the protrusions 19a and 19b
This is the force required to release the biting force between the surfaces 2a and 10a, and no strong force in the axial direction is acting between the female threaded portion 20 of the cap nut 2 and the male threaded portion 15 of the pipe joint body 8. Therefore, this threaded portion will not be damaged or deformed.

In addition, each protrusion 19a and 19b provided on the washer 17
A plurality of projections 19a and 19b are provided at symmetrical positions, so that the respective protrusions 19a and 19b bite into the tip surface 2a of the cap nut 2 and the side end surface 10a of the flange 10 equally with respect to the axis.
The cap nut 2 is not tightened in an inclined state.

Note that the projections 19a and 19 provided on the washer 17
The shape and number of b can be changed as appropriate. Further, the projections 19a and 19b may be provided on the side surface of the washer 17 by cutting the washer body 17a or by welding a metal projection member. In this embodiment, the fastening member 17 is formed of a ring-shaped washer, but it can also be formed, for example, in a U-shape or a U-shape with an open side. In this case, bag nut 2 and slit ring 1
The fastening member can be placed between the flange 10 and the slit ring 1 by fitting it onto the cylindrical portion 14 of the slit ring 1 from the outside.

Further, in the above embodiment, the pipe joint main body 8 is composed of the joint body 3 and the slit ring 1, but it is also possible to use, for example, a joint body 3 and the slit ring 1 formed integrally. Furthermore, in that case, the present invention can also be applied to the pipe joint body 8 in which the guide portion 31 is not formed. The present invention can also be applied to pipe joint bodies 8 that are bent in an L shape, branched in two directions, or branched in three directions.

(Effects of the Invention) As described above, the present invention is arranged on the outside of the cylindrical part of the pipe joint main body in the joint between the collar part of the pipe joint main body and the cap nut, and when the cap nut and the cylindrical part are screwed together, Since the fastening member is equipped with a protrusion that bites into each opposing surface of the cap nut and the flange, when the cap nut is screwed into the pipe joint body and the desired sealing structure is obtained, the protrusion of the fastening member will fit into the cap. The tightening torque of the cap nut increases dramatically as it bites into the opposing surfaces of the nut and the flange of the pipe fitting body, so the operator can easily sense when proper tightening is finished using a tool. be able to. Therefore, even when connecting pipes in places where the connection points cannot be seen, such as in the ceiling or under the floor, you can accurately determine the proper tightening position of the pipe joint, and avoid over-tightening the cap nuts as in the past. This prevents the cap nut and the threaded portion of the pipe joint body from being damaged or deformed, the cap nut can reliably seal the connecting pipe, and it can be tightened with uniform force.

Moreover, since the cap nut will not be over-tightened, even if the pipe fitting body is made of a material that is relatively easily deformed compared to iron, such as synthetic resin, there is no risk of the threaded part being crushed, and the diameter of the threaded part And the length will not be increased. Therefore, it is possible to improve productivity by making the pipe joint body and the cap nut from a synthetic resin material, and it is also possible to provide a relatively small-sized pipe joint with excellent sealing performance.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view showing an example of the pipe joint of the present invention;
Figure 2 is a partially cutaway side view of the pipe joint showing the state in which the connecting pipe is connected, Figures 3 (a) and (b) are front and side views of the fastening member, and Figure 4 is the state in which the connecting pipe is connected. FIG. 5 is an enlarged sectional view of the main part of a pipe joint showing a state in which the connecting pipes of a conventional pipe joint are connected. FIG. 1... Slit ring, 2... Bag nut, 4...
Connecting pipe, 5... Connecting pipe, IO... Flange, 14...
Cylindrical part, 15... Male thread part, 17... Fastening member, 1
9a, 19b...Protrusion, 20...Female screw portion, 2
1... Theba section. that's all

Claims (2)

[Claims] 1. a synthetic resin pipe joint body having a cylindrical part formed with a male thread on the outer periphery and fitted onto the end of the connecting pipe; and a flange protruding toward the outer periphery at the proximal end of the cylindrical part; A female threaded part is formed on the inner periphery of the tip to be screwed into the male threaded part of the pipe joint body, and a tapered part is provided on the inner periphery of the base to reduce the diameter of the tip of the cylindrical part when the two are screwed together. A resin cap nut is disposed outside the cylindrical portion of the pipe joint body between the flange of the pipe joint body and the cap nut, and when the cap nut and the cylindrical portion are screwed together, the bag nut A pipe joint comprising: a fastening member having protrusions that bite into opposing surfaces of a nut and a collar. 2. 2. The pipe joint according to claim 1, wherein the fastening member is formed of a ring-shaped metal washer, and projections are formed on both sides of the washer.