JPH0550531A - Apparatus for manufacturing electrically fusible coupling - Google Patents

Abstract

PURPOSE:To provide an apparatus for manufacturing an electrically fusible coupling capable of simply and readily manufacturing even an electrically fusible coupling with a large diameter or an undercut. CONSTITUTION:An apparatus 1 for manufacturing an electrically fusible coupling is of the type equipped with a core 2 that is allowed to expand and contract in diameter, rotating means 3 for rotating the core 2, a cap mold 4 which is provided on an end part of the core 2 for rotatably supporting the core 2 and designed to construct a part of the mold, and a cover mold 5 that is fitted with the cap mold 4 for covering the whole of the core 2 and defining a predetermined gap in this state between the part itself and the core 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric fusion joint manufacturing apparatus for manufacturing an electric fusion joint by injection molding.

[0002]

2. Description of the Related Art Generally, it is formed in a cylindrical shape, and an end portion of a resin pipe can be fitted to the inner peripheral surface of the resin pipe.
2. Description of the Related Art There is known an electric fusion joint in which a coil that generates heat when energized is embedded.

As a method of manufacturing this electric fusion joint, first, a coil is wound around a cylindrical core, and this coil is set in a mold together with the core. Then, a resin material is injection-molded in the gap between the core and the mold. After that, the molded product was taken out from the mold, and the core was pulled out by hydraulic pressure or air to obtain a product. As a method of reducing the injection amount of resin material, there is also known a method in which a coil is wound around a core, a sheath pipe is covered around the coil, and the resin is set in a mold in this state to perform injection molding. ing.

Conventionally, as a manufacturing apparatus for carrying out such a manufacturing method, a core around which a coil is wound and an injection configured to form a predetermined gap between the core and the core. Molding dies were used.

[0005]

However, when a large-diameter electric fusion-bonded joint is manufactured by the above-mentioned conventional manufacturing apparatus, the core becomes large and becomes heavy at the same time. Therefore, it becomes difficult for human power to wind the coil around the core and set it in the mold, and a special tool is required to set the core in the mold.

Further, when the core is removed from the molded product, the molding resin shrinks, so that a great deal of labor is required, which is a disadvantage.

Further, in order to remove the core from the molded product,
This causes the inconvenience that the product cannot be undercut.

The present invention has been made in view of the above circumstances, and provides an apparatus for manufacturing an electric fusion joint, which can easily and easily manufacture an electric fusion joint having a large diameter and an undercut. It is intended to be provided.

[0009]

According to a first aspect of the present invention, there is provided an apparatus for manufacturing an electric fusion joint, which is formed into a cylindrical shape, and an end portion of a resin pipe is fitted to an inner peripheral surface of the apparatus. It is a fusion splicing joint in which a coil that can be combined and that generates heat when energized is embedded. A coil wound around a core is set in a mold and a resin material is injected into the gap between the core and the mold. In a product manufactured by molding, a core whose diameter can be expanded and contracted, rotating means for rotating the core, and one end portion of the core, which rotatably supports the core and which is used in the mold. And a cover mold adapted to cover the entire core in conformity with the cover mold and to form a predetermined gap with the core in this state. It is a thing.

A second aspect of the present invention for solving the above problems.
The manufacturing apparatus for the electric fusion joint described is formed in a cylindrical shape, and an end portion of the resin pipe can be fitted to the inner peripheral surface of the apparatus, and an electric fusion coil in which a coil that generates heat by energization is embedded is embedded. Coupling, covering the outer circumference of the coil wound around the core with a sheath pipe, and setting the core in the mold in this state,
A resin material is injection-molded in the gap between the core and the mold to produce an electric fusion joint in which the sheath pipe and the resin material arranged in this gap are integrated. , Rotating means for rotating this core,
A lid die is provided at one end of the core and rotatably supports the core and constitutes a part of the die. The lid die is adapted to cover the entire core in conformity with the lid die. And a sheathed mold provided inside the sheathed mold to sandwich the sheath pipe in a state of covering the core to form a predetermined gap between the sheathed pipe and the core and to separate the sheathed pipe from the sheath pipe in the mold open state. It is equipped with an internal mold.

[0011]

According to the manufacturing apparatus of claim 1, first, the core is expanded, the core is rotated, the coil is wound around the core, and after the winding, the lid mold and the covering mold are separated. Close the mold. At this time, since the core is previously rotatably supported by the lid mold, it can be set in the mold without moving the core itself.

Then, after a resin material is injection-molded in the gap between the core and the mold, the mold is opened to reduce the diameter of the core. As a result, the core is detached from the product and the product is taken out.

According to the manufacturing apparatus of the second aspect,
First, the diameter of the core is expanded, the core is rotated, and the coil is wound around the core. Then, after winding, a sheath tube is covered on the outer peripheral portion of the coil, and the lid mold and the covering mold are closed. At this time, since the core is previously rotatably supported by the lid mold, it can be set in the mold without moving the core itself. Further, the sheath pipe is sandwiched by the inner mold provided in the covering mold.

Then, a resin material is injection-molded in the gap between the core and the mold, and then the mold is opened to reduce the diameter of the core. As a result, the core separates from the product, the inner mold separates from the sheath pipe, and the product is taken out.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

[0016]

[Embodiment 1] FIGS. 1 to 4 show a manufacturing process by an apparatus 1 for manufacturing an electric fusion joint.

That is, the manufacturing apparatus 1 includes a core 2 that can be expanded and contracted, a rotating device 3 that rotates the core 2, and a lid mold 4 that cantileverly supports one end of the core 2.
And a coating die 5 which is adapted to form a predetermined gap with the core 2 in conformity with the lid die 4.

As shown in FIG. 5, the core 2 is composed of an inner core 21 and four outer cores 22 slidable on the outer peripheral portion of the inner core 21. The inner core 21 has a length of 4 along the longitudinal direction of the cylindrical body.
The taper surface 23 is formed at one place.
A groove 24 is provided on each tapered surface 23. The outer core 22 has the groove portion 2 of the tapered surface 23.
A rail portion 25 that engages with 4 is formed. And
The outer core 22 has the groove portion 2 by the rail portion 25.
By sliding the tapered surface 23 in the state of being engaged with 4,
It can be expanded and contracted. That is, the outer core 2
With 2 aligned with the inner core 21, a cylindrical core corresponding to the expanded diameter state is formed. Then, the outer core 22 slides on the tapered surface 23 to slide the inner core 2
The outer core 22 is pulled toward the center of the core 2 as it is separated from 1. That is, in this attracted state, the outer core 22 alone forms a core having a substantially cylindrical shape and having a reduced diameter.

In this embodiment, four outer cores 2 are used.
The number of outer cores 22 is not limited to four, but an appropriate number of outer cores 22 may be configured to expand and contract in diameter. ..

The rotating device 3 is constructed such that a shaft 32 provided on the base end side along the central axis of the inner core 21 is driven by a motor 32. That is, the chain 36 is wound between the sprocket 33 provided on the shaft 31 and the sprocket 35 provided on the rotating shaft 34 of the motor 32 to transmit the drive.

The lid die 4 is composed of a fixed lid die 41 adapted to rotatably support the core 2 and a movable lid die 42 adapted to slide the outer core 22. That is, the fixed lid mold 41 rotatably supports the shaft 31 connected to the inner core 21 of the core 2 with the core 2 positioned on the cavity surface side. On the other hand, the movable lid die 42 is provided between the fixed lid die 41 and the core 2, and is adapted to engage only with the outer core 22. The movable lid mold 42 is connected to a rod 43 penetrating the fixed lid mold 41, and reciprocates in conjunction with the movement of the rod 43.
The outer core 22 engaged with the movable lid die 42 is slid by the reciprocating movement of the movable lid die 42. However, the movable lid mold 42 is adapted to engage with the outer core 22 only in the reciprocating direction, and does not hinder the rotation of the outer core 22 by the rotating device 3. That is, when the core 2 rotates, the outer core 22 also rotates, but the engaging portion (not shown) of the movable lid mold 42 engaged with the outer core 22 has a groove on the rotation trajectory of the outer core 22. And the like so as not to rotate with the rotation of the outer core 22.

The covering die 5 covers the entire core 2 in a state where the covering die 5 is closed with the lid die 4. Then, in this mold closed state, a cylindrical gap corresponding to the shape of the joint is formed on the outer peripheral portion of the core 2. Further, the coating die 5 is provided with an injection port 51 for injecting the resin material 6 into a gap formed between the coating die 5 and the core 2.

Next, a method of manufacturing the electric fusion joint by the manufacturing apparatus 1 will be described.

First, the core 2 is expanded in diameter, that is, the movable lid mold 42 is not moved, and the outer core 22 and the inner core 21 are made to coincide with each other. And core 2
The coil 7 covered with the resin layer 71 is temporarily fixed to the outer peripheral portion of the, and the motor 32 is operated. Then, the entire core 2 is rotated, and this rotation is used to make the coil 7
Is wound around the outer periphery of the core 2. After winding, the motor 32
And the resin layers 71 adjacent to each other by a trowel (not shown).
The appropriate position is welded to stabilize the winding state of the coil 7.

Next, the core 2 around which the coil 7 is wound is covered with the coating die 5 to close the die, and the resin material 6 is injected from the injection port 51 of the coating die 5 to sufficiently fill the resin material 6.
After curing, the coating mold 5 is opened.

Then, the movable lid mold 42 is moved by the operation of the rod 43. Then, the outer core 22 is reduced in diameter with the movement of the movable lid mold 42, and is separated from the molded product 60.

Since the molded product 60 molded in this manner is formed into a cylindrical shape having a bottom with the gate mark remaining, the bottom portion which is the gate mark is cut off to form an electric fusion joint having a cylindrical shape. To do.

In the electric fusion-bonded joint manufactured as described above, the end portion of the coil 7 is positioned after the coil 7 is wound, and after manufacturing, an energizing terminal (not shown) is attached to the end portion of the coil 7. May be connected and processed, or a cavity surface corresponding to an energization terminal (not shown) may be formed in the coating mold 5.

[0029]

Second Embodiment This example is shown in FIGS. That is,
Since the manufacturing apparatus 10 only has the inner mold 50 provided inside the coating mold 5 of the manufacturing apparatus 1 of the first embodiment, only the difference will be described here, and the other description will be omitted. The same components as those in the first embodiment are designated by the same reference numerals.

That is, the coating die 5 has a taper surface 52 formed on the inner peripheral surface thereof, the taper surface 52 being reduced toward the inner part.

On the other hand, the inner mold 50 comprises a plurality of movable molds 53 adapted to slide on the tapered surface 52 of the coating mold 5.
A cavity surface is formed on the inner peripheral surface of each movable die 53. When the movable dies 53 slide on the innermost portion of the coating die 5, the movable dies 53 are closed and form a predetermined cavity surface. Further, when each movable die 53 slides in the outer direction of the coating die 5, each movable die 53 is in a mold open state and is separated from the molded product 60 molded on the cavity surface.

Next, a method of manufacturing the electric fusion joint by the manufacturing apparatus 10 will be described.

First, as in the first embodiment, the motor 3
2 is operated so that the coil 7 is wound around the core 2.

Then, as shown in FIG. 6, a sheath tube 8 is put around the coil 7. In this state, the sheath tube 8 has a gap with the coil 7 and is in an unstable state in which it is simply covered around the coil 7.

Then, the core 2 is covered with the coating mold 5 and the mold is closed. Then, the inner mold 50 in the coating mold 5
The diameter of each movable mold 53 constituting the above is reduced, and the sheath tube 8 is clamped and fixed in a stable state.

After that, the resin material 6 is injection-molded so that the sheath tube 8 and the coil 7 are integrated, and after the molding, the coating mold 5 is opened again. Then, each movable mold 53 that holds and fixes the sheath pipe 8 is separated from the sheath pipe 8, and the inner mold 50 and the molded product 60 are easily separated from each other.

After that, the electric fusion joint is obtained in the same manner as in the first embodiment.

[0038]

As described above, according to the manufacturing apparatus of the present invention, the core wound with the coil can be set in the mold without moving the core itself. Even if it is, it can be easily manufactured. Further, by reducing the diameter of the core, the core can be separated from the product and the product can be taken out, so that even a product with an undercut can be easily manufactured.

According to the manufacturing apparatus of the second aspect,
Also in the manufacturing method using the sheath tube, the sheath tube can be easily fixed and detached to manufacture the electric fusion joint.

[Brief description of drawings]

FIG. 1 is a schematic view showing an overall configuration of an apparatus for manufacturing an electric fusion joint according to Example 1, which is a side sectional view showing a state in which a coil is wound around a core.

FIG. 2 is a schematic view showing an overall configuration of an apparatus for manufacturing an electric fusion joint according to Example 1, and is a side sectional view showing a state in which a mold is closed and injection molding is performed.

FIG. 3 is a schematic view showing an overall configuration of an apparatus for manufacturing an electric fusion joint according to Example 1, which is a side sectional view showing a state in which a mold after injection molding is opened.

FIG. 4 is a schematic view showing an overall configuration of an apparatus for manufacturing an electric fusion joint according to Example 1, which is a side sectional view showing a state where a molded product is separated from a core.

FIG. 5 is a front view showing a diameter expansion state and a diameter reduction state of the core.

FIG. 6 is a schematic view showing the overall configuration of an apparatus for manufacturing an electric fusion joint according to Example 2, and is a side sectional view showing a state in which a coil is wound around a core and a sheath pipe is covered.

FIG. 7 is a schematic view showing an overall configuration of an apparatus for manufacturing an electric fusion joint according to Example 2, and is a side sectional view showing a state in which a mold is closed.

FIG. 8 is a schematic view showing an overall configuration of an apparatus for manufacturing an electric fusion joint according to Example 2, which is a side sectional view showing a state in which a mold is opened after injection molding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Manufacturing device 2 Core 3 Rotating device (rotating means) 4 Lid type 5 Covering type 50 Inner type 6 Resin material 7 Coil 8 Saya pipe

Claims (2)

[Claims] 1. An electric fusion joint, which is formed into a cylindrical shape, and an end portion of a resin pipe can be fitted to an inner peripheral surface of the cylindrical portion, and a coil which generates heat when energized is embedded therein. What is manufactured by setting a coil wound around a core in a mold and injection-molding a resin material in a gap between the core and the mold, wherein a core that can be expanded and contracted and a rotating means that rotates this core And a lid die which is provided at one end of the core to rotatably support the core and constitutes a part of the die, and the whole of the core is covered in conformity with the lid die. An apparatus for producing an electric fusion joint, comprising: a coating die configured to form a predetermined gap with the core in this state. 2. An electric fusion joint, which is formed in a cylindrical shape, in which an end portion of a resin pipe can be fitted to an inner peripheral surface of the resin pipe, and in which a coil which generates heat by energization is embedded. Cover the outer circumference of the coil wound around the core with a sheath pipe,
In this state, the core is set in the mold, and the resin material is injection-molded in the gap between the core and the mold to manufacture an electric fusion joint in which the sheath pipe arranged in this gap and the resin material are integrated. In this case, an expandable / reducible core, a rotating means for rotating the core, and one end of the core are provided to rotatably support the core and form a part of the mold. Between the core and the lid type that is made, and the coating type that is adapted to cover the entire core in conformity with the lid type, and that is provided in the coating type and sandwiches the sheath pipe with the core being coated. An apparatus for manufacturing an electric fusion joint, comprising: an inner die formed with a predetermined gap and separated from the sheath pipe in a mold open state.