JP2002071080A - Fitting member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fitting member consists of a metallic connection member and a saddle part having a connection part insert-molded with the connection part, the connection part of the resin tube of the saddle part is dent not impairing the fusion with the resin tube by 'a recess' caused by the cooling nonuniformity of an after forming resin. SOLUTION: The insert part 1a of a metallic connection member 1 is formed by installing it in the shape of saddle extending over a saddle part 2 and the cold nonuniformity of the after forming resin is reduced by reaching the point of an insert part to the inside of the saddle part 2 to cut the thick wall part of the resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal connecting member for connecting a metal pipe, a water faucet or the like, and a connecting surface between the connecting member and an arc-shaped resin pipe formed by insert molding. The present invention relates to a joint member provided with a saddle joint that embeds a heat wire and is electrically fused to a resin tube.

[0002]

2. Description of the Related Art FIGS. 1 and 2 show an example of this type of joint member. The joint member comprises a metal connecting member 1 and a saddle portion 2 having a connecting portion 2a formed by insert molding the connecting member 1. A water tap 3 or a metal pipe as shown in the figure is screwed into and connected to 1, and a heating wire (not shown) is embedded in the saddle portion 2 at the joint surface with the resin pipe, though not shown. , And is electrically fused to the resin tube by energization.

[0003]

The molded product shrinks due to cooling after molding, and a dent called "sink" occurs in a thick portion particularly due to uneven cooling. 1 and 2
In the example shown in (1), it is unavoidable that a thick portion is inevitably generated at the connecting portion a between the connecting portion 2a and the saddle portion 2, and it is easy to cause "sink" in such a thick portion. Depression tends to occur. If such a dent is formed at the joint surface of the saddle portion 2 with the resin tube, there is a problem that fusion with the resin tube cannot be performed at the dent portion.

[0004] An object of the present invention is to provide a joint member which has solved the above-mentioned problems.

[0005]

The invention according to claim 1 has a metal connecting member for connecting a metal pipe, a water faucet, and the like, and a connecting portion formed by insert-molding the connecting member to form a resin having an arc shape. In a joint member having a saddle portion which is embedded with a heating wire in a connection surface with a pipe and which is electrically fused to a resin tube, a saddle-shaped member in which an insert portion of the metal connection member is mounted across the saddle portion. It is characterized by being formed in.

According to the present invention, the insert portion of the metal connecting member has a saddle shape and is buried up to the thick portion of the resin, and the thick portion of the resin alone is eliminated, thereby cooling the resin after molding. The unevenness is reduced, and the crystallinity distribution of the resin is reduced. And, as a result, partial “sink” is reduced.

In the present invention, the connection between a metal pipe or a water faucet or the like and a metal connection member can be made by cutting and screwing both as shown in FIG. The connection can be made by bonding or welding.

The invention according to claim 2 is characterized in that, in the invention according to claim 1, the tip of the insert portion reaches the inside of the saddle portion.

According to the present invention, the formation of "sink" due to uneven cooling of the resin in the saddle portion is prevented.

The invention according to claim 3 is the invention according to claim 1 or 2
In the invention according to the invention, the insert portion is buried in the connection portion, and is entirely in contact with the resin.

According to the present invention, since the insert portion has a large contact area with the resin, the strength is increased, and the resin is less likely to be peeled off when a bending load is applied to the connection portion after the pipe is constructed. .

The invention according to claim 4 is characterized in that, in the invention according to claims 1 to 3, the interface between the insert portion and the resin is a modified polyolefin layer, or the modified polyolefin is mixed into the resin.

According to the present invention, the adhesiveness between the insert portion and the resin can be improved.

The interface between the insert portion and the resin can be made into a modified polyolefin layer by setting a metal connecting member having the modified polyolefin coated on the insert portion in a mold and performing insert molding. In order to coat the modified polyolefin on the portion, various methods known in the art, for example, a method in which the modified polyolefin is heat-fused by an electrostatic coating method or a fluid immersion method, a method in which the modified polyolefin film is heat-fused or made of metal. A method in which the connecting member is heated and fused, a method in which the connecting member is immersed in a solution or an emulsion of the modified polyolefin, and then dried, can be employed. When coating the modified polyolefin, the surface of the insert portion is washed with a strong acidic aqueous solution, a strong alkaline aqueous solution or a detergent in advance, or after or without washing, is treated with a primer with an adhesion modifier such as alkoxytitanium. It is desirable to do. Thereby, stronger adhesiveness can be obtained.

The modified polyolefin or the like coated on the insert is desirably heat-treated in the presence of alcohol. As a result, it is possible to suppress the deterioration with time of the adhesive force between the metal portion and the resin portion. Examples of the alcohol used here include aliphatic alcohols such as isobutyl alcohol, and dihydric alcohols such as ethylene glycogen. Of these, ethylene glycol is preferable.

The heat treatment performed by bringing the modified polyolefin or the like coated on the insert portion into contact with alcohol is usually performed at about 200 ° C. for 30 minutes to several hours.

The thickness of the coating of the modified polyolefin or the like coated on the insert portion is usually in the range of 1 to 10 ⁴ μm, preferably 5 to 5 × 10 ² μm.

As the modified polyolefin, a polyolefin may be an unsaturated carboxylic acid such as acrylic acid or maleic acid;
Examples thereof include those modified by graft copolymerization with at least one modified monomer such as unsaturated carboxylic anhydride such as maleic anhydride, amide of unsaturated carboxylic acid, and unsaturated epoxide such as glycidyl methacrylate.

The content of the modified monomer component in the modified polyolefin is from 0.001 to
It is desirably in the range of 5% by weight. As the modified polyolefin, a composition obtained by blending an unmodified polyolefin with a polyolefin obtained by modifying the entire polyolefin with the above-mentioned modified monomer can be used.

On the other hand, in order to obtain a resin in which the modified polyolefin is mixed in the resin, it is preferable to set a metal connecting member in a mold and injection-mold a resin in which the modified polyolefin is mixed in the resin.

The resin used in each of the above inventions is not particularly limited as long as it is a thermoplastic resin. For example, polyethylene, polypropylene, polybutene-1, polyolefins such as cross-linked polyethylene,
Examples thereof include polyvinyl chloride, polyester, polyamide, and polyacetal.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. In the figures, components having the same structure as those shown in FIGS. 1 and 2 are denoted by the same reference numerals.

In the joint member shown in FIGS. 3 and 4, the insert portion 1a embedded in the resin of the metal connecting member 1 and functioning as a core metal has irregularities inside and outside, so that the resin is The contact area with the resin forms a modified polyolefin layer (not shown).
And it is formed in a saddle shape that can be mounted over the saddle portion 2.

The joint member shown in FIG.
The tip of “a” is provided so as to reach the inside of the saddle portion 2.

[0025]

According to the first aspect of the present invention, the insert portion of the metal connecting member functions as a core metal until the connecting portion between the connecting portion and the saddle portion, and is cooled at the connecting portion by the cooling after molding. Since the shrinkage of the resin is hindered, “sink” is less likely to occur at the joint surface of the portion and the inner surface of the saddle portion, and the electric fusion with the resin tube is performed over the entire joint surface.

According to the second aspect of the present invention, "sink" is less likely to occur at the joint surface, and the electric fusion with the resin tube can be performed more reliably.

According to the third aspect of the present invention, the strength is increased by increasing the contact area between the insert portion and the resin, and the resin is less likely to peel off when a bending load is applied.

According to the fourth aspect of the present invention, by improving the adhesiveness between the insert portion and the resin, it is possible to ensure the water sealing property and increase the bending strength and the like.

[Brief description of the drawings]

FIG. 1 is a front view of a joint member to which a water tap is attached.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a partial cross-sectional front view of the joint member according to the present invention.

FIG. 4 is a sectional view taken along line BB of FIG. 3;

FIG. 5 is a cross-sectional view of another example of the joint member according to the present invention.

[Explanation of symbols]

 1. Connection member 1a Insert part 2, 2a Saddle part 3. Water faucet

Claims (4)

[Claims] An electric heating wire is provided on a connection surface between a metal connection member for connecting a metal pipe, a water faucet, and the like, and a connection portion formed by insert-molding the connection member and an arc-shaped resin pipe. A joint member having a saddle portion embedded and electrofused with a resin tube, wherein the insert portion of the metal connecting member is formed in a saddle shape so as to be mounted across the saddle portion. Element. 2. The joint member according to claim 1, wherein the tip of the insert portion reaches into the saddle portion. 3. The joint member according to claim 1, wherein the insert portion is buried in the connecting portion, and the whole is in contact with the resin. 4. The joint member according to claim 1, wherein the interface between the insert portion and the resin is a modified polyolefin layer, or the modified polyolefin is mixed into the resin.