JPH04145293A - Resin tube takeout coupling - Google Patents

Abstract

PURPOSE:To secure such a resin tube takeout coupling that is easy to manufacture and of sure sealability by enlarging the diameter of a stiffener fitted in the one end side inner surface of a resin short tube, and locking this short tube to a coupling body. CONSTITUTION:A left end side of a polyethylene short tube 3 is fitted in the inner surface of a groove 1b formed on an inner surface at the right end side of a coupling body 1, while a packing 6 is fitted in an intermediate part outer surface of the polyethylene short tube 3, and an outer surface of the packing 6 contacts the right end inner surface of the coupling body 1 and an inner surface of a cylindrical part 2b of a resin covered layer 2. A stiffener 7 with a flange projected outward to the cylindrical left end is fitted in a left end inner surface of the short tube 3, and this stiffener 7 is extended of its diameter larger than the original form, and in the extended state intact, the polyethylene short tube 3 is clamped to the coupling body 1. Since this short tube 3 is bitten into the groove 1b of the coupling body 1, it shows its pull-out inhibiting force, and the packing 6 prevents any leak of internal fluid and, what is more, it prevents any external fluid from penetrating, thus it serves external anticorrosion.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a resin pipe extraction joint for connecting a metal pipe and a resin pipe.

[Prior art] A joint has been proposed in which the part that connects to the A, W, etc., is made of metal, and the part that connects to the resin pipe is made of resin. Conventional such joints are made by injection molding the resin part into a mold that houses the metal part of the joint.
It was made by integrally forming a metal part and a resin part (
Utility Model Publication No. 55-22312, Utility Model Number 59-31987, Utility Model Number 61-18302).

[Problems to be Solved by the Invention] The conventional resin pipe extraction joint described above is manufactured only by injection molding the resin part into a mold that houses the metal part of the joint, so the manufacturing cost is high. There was a problem with that. In addition, since the tightness between the metal part and the resin part is not fixed, if the metal part and the resin part separate due to differences in thermal expansion between the metal part and the resin part due to temperature changes, There was a problem in that the sealing property was immediately destroyed.

Therefore, the present invention aims to provide a material that is easy to manufacture and has a proven sealability.

[Means for Solving the Problems] The present invention has been made to achieve the above object, and includes a joint body having a female thread on one end side and a groove on the inner peripheral surface of the other end m; a resin coating layer that covers the outer surface of the joint body and has individual portions that protrude from the other end side of the joint body;
One end side is fitted into the other end side of the joint body C, the other end side is a resin short tube that protrudes from the other end side of the joint body, the inner surface is in contact with the resin base short tube, and the outer surface is in contact with the other end side of the joint body. Inner surface of end side.

and a gasket in contact with the inner surface of the cylindrical portion of the resin coating layer;
This joint for taking out a resin pipe consists of a stiffener fitted on the inner surface of the one end side of a short resin pipe, and the stiffener is expanded in diameter to fix the short resin pipe to the joint body.

[Operation] When the diameter of the stiffener fitted on the inner surface of one end of the resin short tube is expanded, the diameter of the one end of the resin short tube is also expanded, so the resin short tube is attached to the inner periphery of the other end of the joint body. It bites into the groove formed on the surface and exerts pull-out prevention power.

At the same time, the packing is pressed between the resin short pipe, the inner surface of the other end of the joint body, and the inner surface of the cylindrical portion of the resin coating layer, thereby preventing leakage of internal fluid and entry of external fluid. Embodiment 6 The present invention will be explained with reference to the drawings 6 FIG. 1 is an upper half section and lower half front view of an embodiment of the joint for taking out a resin pipe according to the present invention. A plurality of grooves 1b are formed in the circumferential direction on the inner surface of the right end side.The outer surface of the joint body 1 is covered with a resin coating layer 2, and the resin coating layer 2 is In order to protect the external surface of the joint between the female thread 1a and a metal pipe (not shown), there is a protrusion 2a that protrudes from the left end of the joint body 1. It also has a cylindrical portion 2b protruding from the side.

On the inner surface of the groove 1b formed on the inner surface of the right end side of the joint body 1,
The left end side of the short polyethylene tube 3 is fitted, and the right end side of the short polyethylene tube 3 protrudes beyond the right end side of the joint body 1. A polyethylene pipe 4 is connected to the right end of the short polyethylene pipe 3 by appropriate means. In FIG. 1, the case where the short polyethylene pipe 3 and the polyethylene pipe 4 are connected via the welded pipe 5 by electrofusion or heat fusion is shown by imaginary lines.

A packing 6 is fitted on the outer surface of the intermediate portion of the short polyethylene pipe 3, so that the outer surface of the packing 6 is connected to the joint body 1.
The inner surface of the right end portion of the resin coating layer 2 is in contact with the inner surface of the cylindrical portion 2b of the resin coating layer 2.

In addition, a stiffener 7 having a cylindrical left end protruding collar is fitted on the inner surface of the left end of the short polyethylene tube 3. This collar is used to facilitate positioning of the stiffener 7. It is being formed. stiffener
7 has a diameter expanded from its original shape, and the polyethylene short pipe 3 is fixed to the joint body 1 in the expanded diameter state.Therefore, it is necessary to be able to plastically deform and expand the diameter by external force. In this case, the stiffener 7 is made of copper.

One means of manufacturing a joint is shown, in which a short polyethylene tube 3 having a packing 6 on the outside and a stiffener 7 on the inside is fitted onto the inside of a joint main body 1 with a resin coating layer 2 fixed on the outside. Inserting the jig from the side or left end side 0 Figure shows the case where the jig is inserted from the right end side 7 In this example, this jig is a TialH with a disk fixed to the left end of a round bar.
A rubber bulge consisting of flO, a cylindrical rubber 11 and a cylindrical member 12 fitted into the round bar portion of the T member 10 was used.

In this embodiment, the diameter of the stiffener 7 is expanded by the rubber bulge in two steps. First, the rubber 11 is positioned so that it reaches the groove 1b of the joint body (Fig. 2).
, the T member 10 and the cylindrical member 1 so that the rubber 11 is compressed.
When 2 is pressed, the rubber 11 expands in diameter, so the stiffener 7 also expands in diameter, and therefore the short polyethylene tube 3 also expands in diameter and its outer surface bites into the groove 1b of the joint body. Thereafter, when the compression of the rubber 11 is released, the rubber 11 returns to its original shape, but the copper stiffener 7 is plastically deformed and maintains its deformed shape.

Position it so that it reaches the 6th part of the packing (Fig. 3),
When the rubber 11 is compressed, the rubber 11 expands in diameter, so the stiffener 7 also expands in diameter and maintains its shape.Therefore, the short polyethylene tube 3 also expands in diameter, and the seal 6 connects the short polyethylene tube 3 and the joint body 1. It is pressed between the inner surface of the right end portion and the inner surface of the cylindrical portion 1b of the resin coating layer 2.

In an example in which a short polyethylene pipe 3 with a nominal diameter of 25A is fixed to the joint body 1, the primary diameter expansion force is approximately 2,000 kg-f,
The secondary diameter expansion force is approximately 1. When expanding the diameter with OOOkg-f,
The resin cladding tube 3 was fixed to the joint body 1 without being excessively deformed, and the sealing effect by the packing 6 was also optimal. Note that the primary diameter expansion and the secondary diameter expansion can be performed using the same rubber bulge, or a single diameter expansion can be completed using a larger rubber bulge.6Also, the diameter expansion of the stiffener 7 can be performed by other means. In other words, the present invention does not concern the means for expanding the diameter of the stiffener 7.

This embodiment is constructed as described above, and since the short polyethylene pipe 3 is wedged into the groove 1b of the joint body 1, it exerts a pulling-out prevention force, and the seal 6 is arranged between the short polyethylene pipe 3 and the joint body 1. The polyethylene short pipe 3 and the resin coating layer 2 are pressed together to prevent internal fluid leakage.
The cylindrical portion 2b prevents entry of external fluids and provides corrosion protection on the outer surface. Also, polyethylene short pipe 3
Although the biting into the groove 1b and the pressing of the packing 6 are maintained by the plastic deformation of the stiffener 7, the function of this resin pipe extraction joint will not be impaired even if there is a temperature change, and the polyethylene Although it is not necessary to integrally mold the short pipe 3 with the joint body 1, it is easy to manufacture a joint for taking out a single resin pipe.

[Effects of the Invention] The present invention provides a joint for taking out a resin pipe that is easy to manufacture and has a reliable sealing property between the inside and outside of the joint.

[Brief explanation of the drawing]

FIG. 1 is an upper half section and lower half front view of an embodiment of the present invention, and FIG.
This figure and FIG. 3 are an upper half section and a lower half front view showing one method for manufacturing the same embodiment.

Claims (1)

[Claims] a joint body having a female thread on one end and a groove on the inner peripheral surface of the other end; a resin coating layer covering the outer surface of the joint body and having a cylindrical part protruding from the other end of the joint body; A resin short tube whose one end is fitted into the other end of the joint body and whose other end protrudes from the other end of the joint body, whose inner surface is in contact with the resin short tube and whose outer surface is in contact with the other end of the joint body. comprising a packing in contact with the inner surface of the end side and the inner surface of the cylindrical portion of the resin coating layer, and a stiffener fitted on the inner surface of the one end side of the short resin tube,
A joint for taking out a resin pipe, in which the stiffener is expanded in diameter and the short resin pipe is fixed to the joint main body.