JP3859125B2 - Sleeve type fitting - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pipe joint for connecting a resin pipe or a thin metal pipe, and more particularly to a joint for connecting a pipe by press-fitting a sleeve, which is a component part of the pipe joint, in the pipe axis direction.
[0002]
[Prior art]
Conventionally, there are various methods for joining resin pipes such as polyethylene, polybutene, and polypropylene as fluid transport pipes such as gas pipes and water pipes. There are mechanical-type pipe joints that are connected by compressing the packing body and the biting ring mounted in the joint body and the nut.
In this joint connection method, a bite ring is assembled to the outer surface of the pipe end and a nut is fastened to the joint body with a wrench.
[0003]
[Problems to be solved by the invention]
The above-mentioned conventional mechanical pipe joint has a drawback that the pipe insertion confirmation as to whether or not the pipe has been securely inserted cannot be performed after the completion of the construction, and it is difficult to confirm the tightening degree of the nut. It was easy for the performance to vary.
In this case, the only way to check the quality of the construction after construction is the leak test. If the construction is incomplete, even if it passes the short-term leak test immediately after construction, the pipe will be pulled out or leaked during long-term use. May occur. In order to solve the above-mentioned problems, it is easy to check after construction without causing variations in bonding strength with simple work, and piping can be easily constructed with a relatively small tool, and leakage or destruction over a long period of time. There has been a demand for a pipe joint that does not cause the problem.
[0004]
There is a sleeve-type pipe joint as a new connection method that meets the above requirements. However, when a resin sleeve is used as a part of the sleeve-type pipe joint, the circumferential tension applied at the time of connection and post-construction piping are added. It is important that the sleeve does not crack due to the temperature and pressure of the fluid, so that the fluid does not leak or the tube does not come out, and a good structure for this purpose has been demanded.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the gist of the present invention is to provide a cylindrical portion that fits the inner circumference of a pipe to be connected at the end of the joint body, and has an inner diameter that fits the outer diameter of the pipe. The cylindrical sleeve is positioned on the outer periphery of the cylindrical portion, one end of the sleeve is made large in diameter both inside and outside, the other end is made small in diameter both inside and outside, the cross-sectional area of the stepped portion in the center is reduced, and the sleeve is axially By compressing the tube, the tube is cut (sheared) at a portion having a small cross-sectional area provided in the central portion of the sleeve, and the large diameter portion runs on the outer periphery of the small diameter portion, thereby reducing the diameter of the small diameter portion. A joint that is sandwiched and connected between a main body and a sleeve, and is characterized in that a reinforcing ring is integrally formed or fitted into a large diameter portion of the sleeve.
Further, the reinforcing ring is formed of a coil-wound wire.
[0006]
[Action]
The present invention has the above-described configuration, which is composed of only a joint body and a sleeve. By compressing the sleeve in the axial direction, it is cut (sheared) at a stepped portion having a small cross-sectional area provided in the central portion of the sleeve. By making one part on the outer periphery of the other, the diameter of the inner side is reduced, and the pipe is sandwiched and connected between the joint body and the sleeve.
In addition, it is constructed so that the outer diameter large side runs on the outer diameter small side with the stepped part (sheared part) of the sleeve as a boundary, the sleeve is made of resin, and more than one place on the circumference of the outer diameter small side By providing a notch portion of this to reduce the rigidity and make it easy to reduce the diameter, the sleeve can be sheared and reduced in diameter with a small compression force. Therefore, the tool can be made small and light, and construction is easy.
[0007]
In addition, by attaching a reinforcing ring to the large diameter portion of the resin sleeve, it is possible to cope with the tensile stress in the circumferential direction when the pipe is connected. In addition, even when used for hot water pipes or pipes subject to water hammer, the creep strength can be secured over a long period of time, and no damage will occur, so a long-life joint can be constructed.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a partial cross-sectional view showing a state immediately before starting movement of a ring in a state where a pipe to be connected to a pipe joint according to an embodiment of the present invention is inserted.
Reference numeral 10 denotes a pipe joint, which includes a joint body 11 and a resin sleeve 20. Reference numeral 30 denotes a pipe to be connected. The end portion of the joint body 11 is a cylindrical portion 12 that fits into the inner diameter of the tube 30, and a plurality of sawtooth-shaped convex strips 13 are provided on the outer peripheral surface thereof. Further, a tube end abutting surface 14 is provided at the back of the cylindrical portion 12.
[0009]
A reinforcing ring 201 is integrally formed on the inner periphery of the end portion of the sleeve 20. The material of the reinforcing ring 201 is preferably made of metal, but may be made of a high-strength material such as carbon fiber or glass fiber. Further, a thin portion 21 and a flange portion 22 are provided at one end of the sleeve 20, and a ridge 23 is provided on the inner periphery of the distal end of the thin portion 21. In addition, a thick portion 24 having a large outer diameter is formed at the opposite end. A stepped portion 25 is formed in the central portion of the sleeve 20, and the thin portion 21 and the thick portion 24 are connected. A conical portion 26 is provided on the outer diameter of the thin portion 21. The sleeve 20 is mounted with the ridges 23 locked to the grooves 15 of the main body 11 using elastic deformation.
[0010]
FIG. 2 shows the appearance of the sleeve 20 of the present invention. As shown in the figure, the whole is substantially cylindrical, and a notch 27 is provided from the thin portion 21 toward the stepped portion 25.
FIG. 3 shows a state in which the sleeve 20 is compressed and the connection of the pipe 30 is completed.
The end surface 202 of the flange 22 of the sleeve 20 and the end surface 203 of the thick portion 24 are sandwiched with a tool, and the sleeve 20 is sheared at the uneven portion 25 by pressing until the flange 22 hits the uneven portion 25. The conical portion 26 is inserted while being reduced in diameter on the inner circumference. Accordingly, the diameter of the tube 30 is reduced and pressed against the main body cylindrical portion 12 so as to be sandwiched, and the cutting edge of the protruding portion 13 of the cylindrical portion bites into the inner surface of the tube 30.
[0011]
In order to fully exhibit the pipe joining function of the joint, it is desirable to make the diameter of the thin portion 21 smaller by making the rigidity of the thin portion 21 smaller than that of the thick portion 24 of the sleeve 20. For example, as shown in FIG. 2, the notch 27 is provided in the sleeve 20, and the rigidity is preferably reduced by the compression of the sleeve 20 so that the diameter can be easily reduced.
The feature of the present embodiment is that the reinforcing ring 201 is integrally formed with the thick portion 24 of the sleeve 20, thereby ensuring sufficient strength against the circumferential tensile force applied to the thick portion 24 during connection. Even when used for high-temperature fluids such as hot water piping, sufficient creep strength can be secured over a long period of time.
[0012]
Another feature is that the thick portion 24 and the thin portion 21 are integrally connected and molded, and the sleeve 20 is pre-assembled to the joint body 11, so that the work when connecting the pipes is as follows. All that is required is to insert the tube into the joint and compress the sleeve 20 axially. Therefore, since it is not necessary for the pipe construction company to perform the work of assembling the parts, the possibility of construction mistakes is reduced.
In addition, since whether or not the tube is surely inserted into the joint can be confirmed by visually checking the end portion 31 of the tube 30 against the tube end contact surface 14 from the outside by the notch portion 26 of the sleeve 20, Insufficient insertion of the tube can be prevented.
[0013]
Further, the completion of the compression work of the sleeve 20 can be confirmed by the abutment of the flange portion 22 and the stepped portion 25 of the sleeve 20, and confirmation after construction is easy.
FIG. 4 is an overall external view of the tool 40 and shows an example of a manual type. The tool for pushing the sleeve is not limited to the manual type, and may be an electric type or a hydraulic type.
FIG. 5 shows another embodiment of the present invention, in which a reinforcing ring 204 made of a coil-wound wire is integrally formed on the inner surface of the end portion of the sleeve 200. The other parts are the same as in the example of FIG.
[0014]
FIG. 6 shows another embodiment of the present invention, in which a reinforcing ring 211 is assembled to the outer periphery of the sleeve 210, and the reinforcing ring 211 is resin-molded after injection molding of the resin portion of the sleeve 210 instead of integral molding. It was inserted into the outer periphery of the part.
FIG. 7 shows the appearance of the reinforcing ring 211, and a slit 212 is provided at one end of the reinforcing ring 211 so as to be fitted into the outer periphery of the sleeve 210 using elastic deformation.
[0015]
The feature of the present invention is a joint that functions as two parts when the sleeve 20 is sheared at the center by compression by a tool when connected, and a reinforcing ring is attached to the large diameter portion of the resin sleeve to which a large tension is applied during construction Has been assembled in advance. Therefore, compared to a structure in which two parts are made and combined at the time of pipe connection, the manufacturing cost can be reduced, the labor for construction can be saved, and even the resin sleeve can be destroyed even under severe use conditions. This is a pipe joint that can withstand long-term use.
[0016]
【The invention's effect】
By assembling the sleeve to the joint body in advance, the pipe connection work at the piping construction site requires only inserting the pipe into the joint and compressing the sleeve using a tool, making the work easy and reducing the possibility of construction errors. Become.
Further, by assembling the reinforcing ring to the resin sleeve, it is possible to configure a joint that does not leak or break for a long time.
Moreover, the thrust required for compression can be reduced by greatly reducing the rigidity of the small diameter side of the sleeve. Therefore, the tool can be miniaturized and the operation force can be reduced.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view immediately before connection showing an embodiment of the present invention.
FIG. 2 is a perspective view showing the sleeve of FIG. 1;
FIG. 3 is a partial cross-sectional view after completion of connection with the pipe of FIG. 1;
FIG. 4 is an external view showing a usage state of a tool according to the present invention.
FIG. 5 is a partial cross-sectional view showing another embodiment of the present invention.
FIG. 6 is a partial sectional view showing another embodiment of the present invention.
7 is a perspective view of the reinforcing ring of FIG. 6. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Pipe joint 11 Joint main body 12 Cylindrical part 20,200,210 Sleeve 201,204,211 Reinforcement ring 30 Pipe 40 Tool

Claims (2)

Provided at the end of the joint body is a cylindrical portion that fits the inner periphery of the tube to be connected, and a substantially cylindrical resin sleeve having an inner diameter that fits the outer diameter of the tube is positioned on the outer periphery of the cylindrical portion. One end of the sleeve is made large with both inner and outer diameters, the other end is made smaller with both inner and outer diameters, the cross-sectional area of the stepped portion in the central portion is reduced, and the sleeve is compressed in the axial direction, thereby It is a joint that is cut and connected at a stepped portion, and the pipe is sandwiched and connected between the cylindrical part of the joint body and the sleeve by reducing the diameter of the small diameter part by climbing the outer periphery of the small diameter part. A sleeve-type pipe joint, wherein a reinforcing ring is integrally formed or fitted into the large-diameter portion of the sleeve. The sleeve-type pipe joint according to claim 1, wherein the reinforcing ring is formed of a coil-wound wire.

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