JP2007008125A - Connection method and connection structure of tube, and tube connecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connection method and a connection structure and a connection device for connecting thermoplastic resin tubes mutually with ease and at a low cost. <P>SOLUTION: A heater 3 having a V- or U-shaped sectional periphery is contacted with a connecting part periphery of the tube, to heat and melt the contacted part. Then, a new thermoplastic resin is heated and melted, and is supplied from a nozzle hole 6 of a resin supply device 7 at a position in the melted state, to form excess resin 4 there. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a connection method for connecting pipes made of thermoplastic resin such as a polyethylene pipe (PE pipe), a structure thereof, and a connection device.

  Polyethylene gas pipes that have been rapidly spread and widely used in city gas buried pipes, etc. are durable, lightweight, easy to handle, and have corrosion resistance. It has characteristics that do not remain. Therefore, it can be an ideal gas pipe that is strong against earthquakes. However, in order to connect the pipes, the adhesive must be used only by fusing the same members together. The polyethylene pipe is a thermoplastic resin, and the pipe is generally connected by a special joint. This special joint has an insertion portion for inserting a pair of tubes, and a coil heater is embedded in advance in the vicinity of the inner surface thereof.

Then, electricity is supplied to the coil heater while both pipes are inserted into the joint, and during that time, the inner surface of the joint and a part of the outer peripheral surface of the pipes to be connected are melted (electrofusion fusion) to cool it. By hardening, both pipes were connected together.
In addition, in the case of a butt connection between a pair of tubes, a disk-shaped metal heating element is used, the pipe ends are pressed against both sides of the pair to heat and melt, and then the metal heating element (heater) is removed, The pipes were crimped and connected (butt fusion).

Japanese Utility Model Publication No. 2000-329284 Japanese Patent Laid-Open No. 06-099496

In the former connection method using a special resin joint, since the coiled heating wire is embedded inside the joint, the manufacturing cost of the joint itself becomes extremely high.
Next, in the latter connection method, the ends of the resin are crimped to the heater plate and melted, and then the tubes are crimped after being pulled out, so that the pipes are attached while the heating body is pulled out. During the mating contact, the resin is hardened by cooling, which is not preferable.
Therefore, an object of the present invention is to solve such problems.

The present invention as set forth in claim 1 is a method of connecting pipes of thermoplastic resin (1) (2) to each other,
While the pair of the tubes (1) (2) are in contact with each other or in proximity to each other, the heating body (3) is heated by contacting the outer surface of the connection portion of the pair of tubes (1) (2). (2) a heating and melting step for melting a part of
In the molten state, a new resin is melted and supplied, and a surplus forming step for forming a surplus (4) on the outer periphery of the connection portion;
It is the connection method of the pipe | tube which comprises this.

The present invention according to claim 2 is the method according to claim 1,
This is a pipe connection method in which groove processing is performed in advance on the connection portion of the pair of pipes, and the heating body (3) is brought into contact with the groove surface.

  The present invention according to claim 3 is a connection structure connected by the method of claim 1 or claim 2.

According to a fourth aspect of the present invention, in the pipe connecting device for connecting the thermoplastic resin pipes to each other,
A heating body (3) in which the outer periphery of the cross section is formed in a V-shape or U-shape, contacts the outer periphery of the connecting portion of the tube, and heats and melts the contact portion;
A resin supply device (7) having a nozzle hole (6) at the end of the heating body (3), heating and melting a new thermoplastic resin, and extruding it from the nozzle hole (6);
It is the pipe | tube connection apparatus which comprises.

The present invention according to claim 5 is the invention according to claim 4,
It is a pipe connecting device provided with air jetting means (8) for jetting air toward the pipe connecting portion from or near the heating body (3).

A sixth aspect of the present invention provides the method according to any one of the fourth to sixth aspects,
The heating body (3) and the tip of the resin supply device (7) are pivotally or slidably connected so that the position of the nozzle hole (6) can be changed with respect to the heating body (3). It is the comprised pipe | tube connection apparatus.

  In the pipe connection method of the present invention, a heating body is brought into contact with a connection portion of a pair of pipes and heated, and a part of both pipes is melted, and a new resin is melted at a position in the molten state. And a surplus forming step for forming a surplus on the outer periphery of the connecting portion. For this reason, the connecting portions of the two pipes are melted together, and the two pipes can be integrated at the connecting portion, and the connection reliability can be ensured.

  In the above connection method, the pipe connection portion is preliminarily grooved, and when the heating body is brought into contact with the groove surface, when the new resin is melted there to form a surplus, the connection portion Deeper parts can be integrated with each other.

The connection structure connected by the above connection method is highly reliable.
Further, the pipe connecting device of the present invention has a heating body 3 whose outer periphery is formed in a V shape or a U shape, a nozzle hole 6 at the end of the heating body 3, and a new thermoplastic resin. And a resin supply device 7 that is melted by heating and pushed out from the nozzle hole 6. The pipe can be easily connected by a simple device having such a structure. Then, by supplying the resin from the nozzle hole 6 of the resin supply device 7 to the end portion of the heating body 3, a new surplus is formed while maintaining the molten state in the molten portion of the pipe connecting portion, and the connection reliability is increased. It becomes a high quality thing.

  The said structure WHEREIN: The means to eject air from the heating body 3 or its vicinity to the connection part of a pipe | tube can be provided. In this case, it is possible to prevent the resin in the pipe connection portion melted by the heating body 3 from drooping downward, and in particular, connection on the lower surface side of the pipe can be easily performed. That is, the dripping of the resin can be prevented by the air.

  In the above-described configuration, the heating body 3 and the tip of the resin supply device 7 can be pivotally or slidably connected so that the position of the nozzle hole 6 can be changed with respect to the heating body 3. In this case, the moving direction of the heating body 3 is changed by changing the position of the nozzle hole 6 with respect to the heating body 3, and the apparatus is moved in an arbitrary direction around the pipe according to the situation at the site. Therefore, it is possible to avoid obstacles, rotate in a direction that is easier to perform, and perform quick work.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partially broken longitudinal sectional view of a pipe connecting device according to the present invention, FIG. 2 is a perspective view of a tip portion of the resin supply device 7, and FIG. 3 is a schematic view of a heating body 3 used in the device. It is. 4 is a perspective explanatory view showing the use state of the apparatus, and FIG. 5 is a cross sectional explanatory view thereof.

  This pipe connection device has a resin supply device 7 and a heating body 3 as shown in FIG. The resin supply device 7 is formed of a material such as a metal material or a fluororesin (trade name Teflon (registered trademark) as an example) in a cylindrical shape, and is formed in a taper in which the inner diameter of the tip portion is gradually narrowed. 6 is provided. An electric heater 9 made of nichrome wire or the like is arranged in a coil shape inside the resin supply device 7. In place of the coiled heat transfer heater 9, a ceramic heater, a silicon rubber heater, or other known heaters can be used. When the coiled electric heater 9 and the metal cylinder 13 are used, an electrical insulating means is provided between them.

  An opening 27 is provided at the rear end portion of the cylinder 13, from which a rod-like or granular thermoplastic resin 19 can be inserted. A piston 14 is provided in the cylinder 13 so as to freely enter and exit, and its rod 15 extends in the axial direction. In this example, a handle 11 is fixed to the rear end of the cylinder 13, a lever 12 that is rotatable with respect to the handle 11 is provided, and a rod pusher plate 24 is attached to the tip thereof.

  The rod pusher plate 24 has a hole slightly larger than the diameter of the rod 15, which penetrates the rod 15. A lever return spring 16 is provided between the rod push-out plate 24 and the bridging portion 28 of the cylinder 13, and biases the lever 12 to the position shown in the figure. Further, a clutch plate 18 is provided outside the handle 11, and a rod 15 passes therethrough. A clutch spring 17 is provided between the clutch plate 18 and the handle 11. Further, a power cable 10 is connected to the cylinder 13 so that power can be supplied to the electric heater 9.

  Next, the heating element 3 is integrally connected to the cylinder 13 in this example. As shown in FIG. 2, the heating body 3 is formed in a V-shaped cross section, and one end thereof is adjacent to the nozzle hole 6 of the resin supply device 7. In this example, the heating body 3 is adapted so that the edge of the valley portion having a V-shaped cross section is curved in an arc shape in the longitudinal direction so as to be adapted to the connection portion. This may be a short straight line. An electric heater 9 is disposed inside the heater 3 as shown in the schematic diagram of FIG. In addition, the front-end | tip part of the cross-sectional V character of the heating body 3 may be a sharp shape, or may be slightly circular arc shape. Further, the heating body 3 may be formed in a U-shaped cross section.

(Pipe connection method)
Next, a method for connecting the thermoplastic pipe 1 and the pipe 2 with the pipe connecting apparatus of the present invention will be described.
In FIG. 1, the clutch plate 18 is pushed downward against the urging force of the clutch spring 17, and the rod 15 is pulled upward. Then, the thermoplastic resin 19 is inserted into the cylinder 13 from the opening 27. The resin 19 is made of the same material as the pipes 1 and 2 connected to each other. Then, electric power is supplied to the electric heater 9, the inner surface of the cylinder 13 is heated to melt the resin 19, and the outer periphery of the heating element 3 is heated.

Next, in the state of FIG. 1, the lever 12 is reciprocated around the shaft 29 in the direction of the arrow, and the rod 15 is pushed downward. In the returning operation of the lever 12, the clutch plate 18 bites in the penetrating portion of the rod 15, and the rod 15 itself is prevented from moving backward.
Therefore, as shown in FIGS. 4 and 5, the heating element 3 is brought into contact with the connection portion between the pipe 1 and the pipe 2. In this example, the pipe 1 is a main pipe 20 having a large diameter, and the pipe 2 is a branch pipe 21 having a small diameter. When the connecting portion is melted by the heating body 3, new molten thermoplastic resin is pushed out from the resin supply device 7 through the nozzle hole 6. For this purpose, the lever 12 in FIG. The position where the molten resin is supplied is a place where the molten resin is in a molten state. In FIG. 4, the molten resin is supplied from the nozzle hole 6 while slightly moving the resin supply device 7 from the state shown in FIG.

Therefore, the pipe connection method of the present invention comprises a heating and melting process in which the heating body 3 is heated by contacting the outer surface of the connection portion of the pipe 1 and the pipe 2 and melted, and a new resin is provided at a position in the molten state. And a surplus forming step of forming surplus 4 there.
In the example of FIG. 5, a groove working portion 5 is formed in the hole edge portion of the hole 30 of the tube 1 and the tip portion of the tube 2, and the outer periphery of the heating body 3 is brought into contact therewith to each groove working portion. 5 is melted. And the surplus 4 is provided in the fusion | melting part. By doing in this way, in the connection part of the pipe | tube 1 and the pipe | tube 2, resin can be fuse | melted and integrated to a deeper position.

  Next, FIGS. 6 and 7 show another example of the pipe connection device of the present invention. In this example, the resin supply device 7 and the heating body 3 are connected by a connection body 31, and the resin supply device 7 is of a syringe type. It is. The heating element 3 is integrated with a casing 32 in which a fan 22 is housed. An air supply hole 25 is provided in the electric heater 9. This pipe connecting device is provided with air jetting means 8 for preventing the molten resin from flowing downward when the pipe is connected on the lower surface side in the gravity direction.

  That is, when the groove portions of the pipe 1 and the pipe 2 are melted by the heating body 3, especially when it is in the lower position, air is ejected from the air supply holes 25, thereby preventing the molten resin from drooping. . In this example, an electric heater 23 is disposed in the casing 32, and the air ejected from the air supply holes 25 is heated to some extent.

  Next, FIG. 8 and FIG. 9 show another example of the pipe connecting method of the present invention. In this example, a threaded portion 33 is provided in advance at the hole 30 in which the groove processing portion 5 is formed and the tip of the tube 2 respectively. The tube 1 and the tube 2 are screwed and fastened with a screw portion 33. Subsequently, the surplus 4 is formed at the connecting portion in the same manner as described above by the pipe connecting device of the present invention. By doing in this way, the pipe | tube of the pipe | tube 1 and the pipe | tube 2 can be connected more firmly and reliably. At the same time, both pipes can be fixed at the time of pipe connection, and the connection work can be performed easily and quickly.

  Next, FIGS. 10 and 11 show still another example of the connection device of the present invention. In this example, the tip of the resin supply device 7 is located at the center of the heating body 3, and a hole is formed in the heating body 3. 34 is provided, and the nozzle hole 6 is opened at one end of the heating element 3. This apparatus has a good balance in connection work and can improve work efficiency.

  Next, FIG. 12 shows another example of the heating element 3 of the pipe connecting device of the present invention. In this example, the electric heaters 9 attached to the heating element 3 are arranged in a meandering manner, and the pitch of the meandering is different. is there. That is, in the section a, the pitch is small and the temperature is higher in that part. In addition, the pitch of b and c is coarser, and the temperature is relatively low in that portion. And the nozzle hole of the resin supply apparatus 7 which is not illustrated in this example is located in the edge part of a section. Then, the heating element 3 is moved from the right to the left as shown by the arrow in the figure. And a pipe | tube connection part is fuse | melted only in the vicinity of the area a of the heating body 3, and it can connect the resin pipes efficiently and reliably.

  Next, FIG. 13 shows the example in FIG. 12 in which the heating body 3 is rotatably provided on the outer periphery of the tip of the resin supply device 7 via a pivot part 35. That is, the heating body 3 is rotated 180 degrees in the direction of the arrow with respect to the axis of the resin supply device 7 to change the state of FIG. (A) to the state of (B), and the position of the nozzle hole 6 is reversed. can do. In the case of (A), the heating body 3 and the resin supply device can be moved from the right to the left, and the resin material can be supplied to the connecting portion of the pipe.

  In the case of the state (B), it is the reverse of the above. In this way, the moving direction of the heating element 3 is changed, the apparatus is moved in an arbitrary direction around the pipe according to the situation at the site, thereby avoiding obstacles, moving the apparatus in a direction that is easier to perform, and quickly I can work.

  Next, in FIG. 14, for the same purpose, one end of the heating body 3 is rotatably provided on the outer periphery of the distal end portion of the resin supply device 7 via a pivot portion 35. For the same purpose, in the example of FIG. 15, a connecting body 31 is provided at one end of the heating body 3, and the connecting body 31 is connected to the distal end portion of the resin supply device 7 via a pivoting portion 35. is there.

The partially broken longitudinal cross-sectional view of the pipe connection apparatus of this invention. The perspective schematic diagram of the front-end | tip part of the same apparatus. Explanatory drawing of the heating body 3 used for the apparatus. The connection method explanatory drawing which connects the joint of the pipe | tube 1 and the pipe | tube 2 with the same pipe | tube connection apparatus. FIG.

Explanatory drawing of the 2nd pipe | tube connection apparatus of this invention. FIG. Explanatory drawing which shows the 2nd example of the pipe connection method of this invention. FIG. The principal part longitudinal cross-sectional view which shows the further another example of the pipe | tube connection apparatus of this invention.

XI-XI arrow schematic cross-sectional view of FIG. Explanatory drawing which shows the other example of the heating body 3 of the pipe | tube connection apparatus of this invention. The principal part longitudinal cross-sectional view which shows the further another example of the pipe | tube connection apparatus of this invention. The principal part explanatory drawing which shows the further another example of the pipe | tube connection apparatus of this invention. The principal part longitudinal cross-sectional view which shows the further another example of the pipe | tube connection apparatus of this invention.

Explanation of symbols

1, 2 Tube 3 Heating element 4 Extra 5 5 Groove processing part 6 Nozzle hole

7 Resin supply device 8 Air jetting means 9 Electric heater
10 Power cable
11 Handle
12 Lever

13 cylinders
14 Piston
15 rod
16 Lever return spring
17 Clutch spring
18 Clutch plate

19 Resin
20 Main
21 Branch
22 fans
23 Electric heater
24 Rod extrusion plate

25 Air supply holes
26 Air
27 opening
28 Cross-linking part
29 axes
30 holes

31 Connector
32 casing
33 Screw part
34 Drilling holes
35 pivot joint

Claims (7)

Thermoplastic tube (1) (2) In the method of connecting together,
While the pair of the tubes (1) (2) are in contact with each other or in proximity to each other, the heating body (3) is heated by contacting the outer surface of the connection portion of the pair of tubes (1) (2). (2) a heating and melting step for melting a part of
In the molten state, a new resin is melted and supplied, and a surplus forming step for forming a surplus (4) on the outer periphery of the connection portion;
A method for connecting pipes comprising: In claim 1,
A method for connecting pipes, wherein a groove processing is performed in advance on the connection portion of the pair of pipes, and the heating body (3) is brought into contact with the groove surface.   The connection structure connected by the method of Claim 1 or Claim 2. In a pipe connection device for connecting thermoplastic resin pipes to each other,
A heating body (3) whose outer periphery is aligned with the outer periphery of the connecting portion of the tube, and that contacts the outer periphery of the connecting portion of the tube to heat and melt the contact portion;
A resin supply device (7) having a nozzle hole (6) at the end of the heating body (3), heating and melting a new thermoplastic resin, and extruding it from the nozzle hole (6);
A pipe connection device comprising: In claim 4,
A pipe connecting device in which the outer periphery of the cross section of the heating body (3) is formed in a V shape or a U shape. In claim 4 or claim 5,
A pipe connection device provided with an air jetting means (8) for jetting air toward the pipe connection from the heating body (3) or its vicinity. In any one of Claims 4-6,
The heating body (3) and the tip of the resin supply device (7) are pivotally or slidably connected so that the position of the nozzle hole (6) can be changed with respect to the heating body (3). Pipe connection device.

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