JPH1016013A - Manufacture of electrically fusion-bonded joint and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the automation of a dismounting/assembling step for a core in a manufacturing step for an electrically fusion-bonded joint. SOLUTION: A molding is transferred to a dismounting/assembling device, and a flange 14 of both end parts of cores 2 is held by the flange holding means 16 of the dismounting/assembling device, and the flange holding means 16 of moved while the electrically fusion-bonded joint 1 is fixed with a clamping plate 13 to pull out the cores 2 to transport the electrically fusion-bonded joint 1. Next, a core guide 18 is moved to a position meat a fitting part to return one of the cores 2 to a specified position and return the other core 2 to a specified position being guided with the core guide 18, and finally the cores 2 are assembled together by fitting one into the other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing an electric fusion joint, and more particularly, to an injection-molded electric fusion joint after injection-molding an electric fusion joint in which a heating wire is embedded. The present invention relates to a method and an apparatus for disassembling a core from inside, pulling out the core, fitting the core again and assembling the core.

[0002]

2. Description of the Related Art In recent years, as a joint for connecting a gas pipe and a resin pipe for water supply and hot water supply, an electric fusion joint having a heating wire embedded in an inner peripheral surface of a receiving port has been used. The connection of the resin tube by this electric fusion joint is performed by inserting a resin tube connected to the sockets at both ends of the joint, connecting a power supply to terminal pins provided at terminal portions at both ends of the joint, and causing the heating wire to generate heat. This is performed by fusing.

[0003] Generally, such an electric fusion joint is manufactured by winding a heating wire around an outer peripheral surface of a core forming the inside of the electric fusion joint and then connecting terminal pins to both ends of the heating wire. And a terminal processing step, wherein the heating wire is wound in a coil shape, and a terminal pin for mounting a terminal pin for forming a terminal portion of a joint is provided at a tip end of the terminal pin of the core having terminal pins connected to both ends thereof. A mounting step, a core mounting step of mounting a core together with a terminal pin into a mold of an injection molding machine, a molding step of injecting a molten resin into a mold to form an electro-fusion joint, and an injection-molded product , A take-out process for taking out a molded product in which a core, a terminal and a terminal pin are integrated, a gate cutting process for cutting a gate molded together with the product, and a terminator molded integrally with the product. A terminal pin withdrawing process to remove pins from the molded product, a slow cooling process to lower the temperature of the product to stabilize its dimensions, disassemble and pull out the core from the product, remove the product, and reassemble the core A method including a core disassembly / assembly process is employed.

[0004]

In each of the above steps,
The core disassembly / assembly step involves extracting the core from the inside of the electrofusion joint, which is an injection-molded product. As shown in the sectional views of FIGS. 6 and 7, the electrofusion joint (product) 1 is removed. Since the core 2 to be molded has undercut portions 3 on both sides from the shape of the inner peripheral surface of the product, the core 2 to be molded has a straight shape as shown in FIG. The core 2 is formed in a two-part structure having a fitting portion 4 at the center thereof.
Must be divided and disassembled at the fitting portion 4 and pulled out from both ends of the product 1 separately.

[0005] The fitting portion 4 of the core 2 cannot withstand a resin pressure during injection molding and prevents molten resin from entering the joint surface to form burrs, so that sufficient clearance cannot be provided. . Therefore, when the core 2 is divided and extracted from the product 1 and then the fitting portion 4 is fitted again to assemble the core 2, if the clearance is small, if there is a slight misalignment or inclination, accurate It becomes difficult to fit.

In consideration of automating the disassembling and assembling process of the core, in order to solve the above-described problem at the time of assembling and fitting, the core is accurately removed from the product at the time of disassembly in the axial direction. It is necessary to pull out without tilting. Then, it is necessary to fit the cores at the time of assembling while maintaining the state.

Further, in the case of an elbow-shaped core, it is necessary to pull out the core having a convex shape at the fitting portion first at the time of disassembly due to the uneven shape of the core fitting portion. Conversely, when assembling, it is necessary to accurately position the core having the concave shape first at the assembly position, and then to accurately move the core having the convex shape to the assembly position to reliably fit the concave and convex. For this reason, conventionally, the step of detachably attaching the core flange to a hydraulic cylinder or the like, extracting the core one by one from the product, and reassembling the core has been performed while checking the position and the like manually.

Accordingly, an object of the present invention is to provide a method and an apparatus for manufacturing an electro-fusion joint which can automate the above-described core disassembly and assembly steps.

[0009]

In order to achieve the above object, a method of manufacturing an electro-fusion joint according to the present invention is characterized in that a heating wire is wound around an outer peripheral surface forming the inside of the electro-fusion joint, and A core having terminal pins connected to both ends of the heating wire together with a terminal pin for forming a terminal portion of an electrofusion joint is mounted in a mold of an injection molding machine, and injection molding is performed. After removing the molded product in which the joint and the core and the terminal pin are integrated, remove the terminal pin, disassemble the core in the molded product, separate it from the electrofusion joint, and re-perform the outer periphery of the core. In a method of assembling a core for winding a heating wire on a surface, a step of transferring the molded article to a disassembling and assembling apparatus of the core by a conveying means, and a pair of flange gripping means provided on the disassembling assembling apparatus, Provided at both ends A step of clamping the flanges from both sides thereof, and moving the flange gripping means while axially fixing the end face of the electrofusion joint by a fixing plate provided in the disassembly assembly apparatus, disassembling the core at the fitting portion; A step of pulling out the electrofusion joint from the inside of the electrofusion joint, a step of taking out the electrofusion joint after extracting the core from the disassembly / assembly apparatus by the conveyance means, and conveying the same; Moving to a predetermined position in the vicinity, returning to a predetermined position while guiding one of the disassembled cores with a core guide, and returning the other core to a predetermined position while guiding the core with a core guide; Performing the fitting step and the step of retracting the core guide to a predetermined position and releasing the flange gripping means, and taking out and transporting the assembled core by the transporting means. It is characterized.

In the apparatus for manufacturing an electric fusion joint of the present invention, a heating wire is wound around an outer peripheral surface forming the inside of the electric fusion joint, and terminal pins are connected to both ends of the heating wire. The core is mounted in a mold of an injection molding machine together with a terminal pin for forming a terminal portion of the electrofusion joint, and injection molding is performed.The molded electrofusion joint, the core and the terminal pin are integrated. After removing the molded product from the mold and removing the terminal pins, the core in the molded product is disassembled and separated from the electro-fusion joint, and the core is wound again around the outer peripheral surface of the core. In the apparatus for manufacturing an electro-fusion joint, a pair of flange gripping means for respectively holding flanges provided at both ends of the core from both surfaces thereof, and moving the flange gripping means from within the electro-fusion joint Pull out the core Core withdrawing means, a fixing plate for fixing the electrofusion joint by fixing the end face of the electrofusion joint in the axial direction when the core is pulled out, and a predetermined position of the fitting portion of the core when assembling the disassembled core. And a core guide for guiding the guide.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings. 1 to 5 each show an embodiment of the present invention. FIG. 1 is an explanatory view showing a core disassembling procedure in a core disassembling / assembling process, and FIG. 2 is an explanatory view showing the same core assembling procedure. 3 is a side view of the disassembly / assembly apparatus, FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. 3, and FIG. 5 is a schematic view for explaining the flange gripping means and the core extracting means.

First, a disassembly and assembling apparatus for disassembling and assembling the core 2 includes an electrofusion joint 1 part of a molded article 11 in which the electrofusion joint 1 after injection molding and the core 2 are integrated. Product receivers 12 for mounting and holding, and a fixing plate 1 for fixing both end faces of the electrofusion joint 1 in the axial direction.
A core receiver 15 for supporting the core 2 between the flanges 3 and 13 and a flange 14 provided outside the fixing plate 13 and at an end of the core 2, and the flange 14 of the core 2 is removed from both surfaces thereof. A pair of flange gripping means 16 for sandwiching each;
The core pulling means 17 for moving the flange gripping means 16 in the pulling direction of the core 2 to pull the core 2 out of the electrofusion joint 1 and the core 2 when the disassembled core 2 is fitted and assembled. And a core guide 18 for guiding the fitting portion 4 to a predetermined position.
After a certain cooling time, is transported to the disassembly / assembly apparatus by ordinary transport means such as a transport robot, and is placed on the product receiver 12 and the core receiver 15. The fixing plate 13 is formed in a substantially U-shape with an open top.
The molded product 11 is positioned by contacting both end surfaces of the electrofusion joint 1 with the fixing plate 13.

[0013] After the transport means has retreated from the disassembly and assembly apparatus,
As shown in FIG. 1 (A), the flange gripping means 16 operates to clamp the flange 14 of the core 2 from both sides. The flange gripping means 16 is for positioning the core 2 by sandwiching the flange 14 of the core 2 and for bearing a load when the core 2 is pulled out from the electrofusion joint 1. And a second chuck 16b which presses against the surface of the flange 14 on the core receiving 15 side. The first chuck 16a is provided with a cylinder 16c for crimping, and the second chuck 16b is formed in a substantially U-shape with an open top for inserting the core body. Further, the flange holding means 16 is provided with the core extracting means 1.
7 is provided on the slider 17a.

The core pulling means 17 comprises a slider 17a on which the flange gripping means 16 is installed, a guide rail 17b for guiding the slider 17a, and a cylinder 17c for generating a core pulling force. The rail 17b is formed so that the core 2 can be accurately moved.

Next, the flange holding means 16 holding the flange 14 as described above is replaced with the core extracting means 17.
Moves in the direction of pulling out the core 2 from the inside of the electrofusion joint 1 via the slider 17a by the action of the cylinder 17c, and the core 2 divided from the fitting portion 4 is pulled out from one end of the electrofusion joint 1. .

In the case of a straight-shaped electrofusion joint such as a socket, the core 2 may be pulled out in either direction or both at the same time. In the case of the elbow shape as shown, the core to be pulled out first is determined by the concave and convex shape of the fitting portion 4, and the core is pulled out one by one in this order.

That is, as shown in FIG. 1 (B), a core 2 having a convex shape 4a in a fitting portion 4 is first placed on an electrofusion joint 1
1C, the core 2 having the concave portion 4b in the fitting portion 4 is pulled out from the other end of the electrofusion joint 1 as shown in FIG. The pulling load of the core 2 varies depending on the product size and product type.
In the case of A elbow, it is about 1 ton.

After the cores 2 are pulled out from both sides of the electrofusion joint 1 in this manner, the electrofusion joint 1 remaining on the disassembly / assembly apparatus is carried out to a predetermined place by a conveying means.
The process proceeds to the core 2 assembling process shown in FIG.

First, as shown in FIG. 2A, the core extracting means is operated in the reverse direction to return the core 2 having the concave shape 4b to the fitting portion 4 to the original dismantling start position, and the core guide 18 Is moved to a predetermined position near the fitting portion 4 of the core 2 and set. This core guide 18 is usually formed in a cylindrical shape because it supports and guides the outer periphery of the core 2.
In addition, since it is necessary to set the core 2 in the radial direction, for example, in the vertical direction, and to remove the core 2 after assembling, the core 2 is inevitably divided. Can be set arbitrarily.

After the core guide 18 is set at a predetermined position, the core 2 having the convex shape 4a is inserted into the fitting portion 4 into the core guide 18, and the uneven portion of the fitting portion 4 is fitted. The fitting at the fitting portion 4 is usually about H7, h7, and its length is several tens of mm. Therefore, even a slight displacement or inclination of the core 2 affects the assembling work. Therefore, by using the core guide 18 manufactured with a predetermined accuracy, it is possible to prevent the displacement and the inclination of the core 2, and the fitting and assembling of the core 2 can be performed smoothly.

After assembling the core 2 in this manner, as shown in FIG. 2C, the core guide 18 is retracted, and the flange 1 is
The holding state of the core 4 is released, and the core 2 is transported from the disassembly / assembly apparatus to a predetermined place by the transporting means, and the disassembly and assembly work of the core 2 is completed.

By disassembling and assembling the core 2 in the above-described procedure using the above-described apparatus, the electric power after injection molding can be obtained using a well-known conveying means such as a conventionally used conveying robot. The core 2 can be formed simply by transporting the molded article 11 in which the fusion joint 1 and the core 2 are integrated to the disassembly / assembly apparatus.
Can be automatically disassembled.

[0023]

As described above, according to the present invention,
The disassembly and assembly process of the core in the manufacturing process of the electro-fusion joint can be automated, and the productivity of the electro-fusion joint can be greatly improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a core disassembly procedure.

FIG. 2 is an explanatory diagram showing a procedure for assembling a core.

FIG. 3 is a side view of the disassembly / assembly apparatus.

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

FIG. 5 is a schematic view of a flange holding means and a core extracting means.

FIG. 6 is a sectional view showing an elbow-shaped core and a molded state of a product.

FIG. 7 is a sectional view showing a straight core and a molded state of a product.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electrofusion joint (product), 2 ... Core, 3 ... Undercut part, 4 ... Mating part, 11 ... Molded product, 12 ... Product receiving,
13: fixing plate, 14: flange, 15: core receiver, 16
... Flange gripping means, 17 ... Core pull-out means, 18 ... Core guide

Claims (2)

[Claims] An electric welding wire is wound around an outer peripheral surface forming the inside of an electric fusion joint, and a core having terminal pins connected to both ends of the electric heating wire forms a terminal portion of the electric fusion joint. Injection molding is carried out by mounting in a mold of an injection molding machine together with a terminal pin for performing molding, and a molded product in which the molded electrofusion joint, the core and the terminal pin are integrated is taken out of the mold, and the terminal pin is removed. After removing, the core in the molded article is disassembled and separated from the electro-fusion joint, and in a method of assembling the core to wind a heating wire again on the outer peripheral surface of the core, The step of transferring to the core disassembly and assembly device, and a pair of flange gripping means provided in the disassembly and assembly device,
A step of clamping the flanges provided at both ends of the core from both surfaces thereof, and moving the flange gripping means while axially fixing the end face of the electrofusion joint by a fixing plate provided in the disassembly and assembly apparatus, Disassembling the core at the fitting portion and pulling it out of the electrofusion joint; removing the core from the electrofusion joint after the core has been pulled out from the disassembly assembly device by the transport means; and transporting the core. Moving the core guide to a predetermined position near the fitting portion of the core, returning one of the disassembled cores to a predetermined position while guiding the other core by the core guide, and guiding the other core by the core guide. Returning to the position and fitting the core with the one core, retracting the core guide to a predetermined position, releasing the flange gripping means, and removing the assembled core by the transporting means. Method of manufacturing an electro-fusion joint and performing a step of conveying to. 2. A core in which a heating wire is wound around an outer peripheral surface forming the inside of the electrofusion joint, and a terminal pin is connected to both ends of the heating wire to form a terminal portion of the electrofusion joint. Injection molding is carried out by mounting in a mold of an injection molding machine together with a terminal pin for performing molding, and a molded product in which the molded electrofusion joint, the core and the terminal pin are integrated is taken out of the mold, and the terminal pin is removed. After removing, the core in the molded article is disassembled and separated from the electro-fusion joint, and the manufacturing apparatus of the electro-fusion joint for assembling the core to wind the heating wire around the outer peripheral surface of the core again, A pair of flange gripping means for holding the flanges provided at both ends of the core from both sides thereof, a core pulling means for moving the flange gripping means to pull the core out of the electrofusion joint, and a core pulling means. When unplugging A fixing plate for fixing the end face of the gas fusion joint in the axial direction to fix the electric fusion joint, and a core guide for guiding a fitting portion of the core to a predetermined position when assembling the disassembled core. An apparatus for manufacturing an electric fusion joint.