JP2501192Y2 - Core type for molded products with metal pieces - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to a core mold for a metal piece-attached molded product which is inserted in a state where the metal piece is partially exposed.

2. Description of the Related Art FIG. 3 shows a coil bobbin 1 of a crank angle sensor as an example of a molded product with a metal piece. This coil bobbin 1 is integrally injection-molded as a whole, has a bobbin part 2 around which a coil (not shown) is wound, and has a flange-shaped mounting part 3 formed on the base end side. Along with
A connector portion 4 that fits with a coupler (not shown) is formed in an obliquely protruding shape. And this coil bobbin 1
Has a central hole 5 composed of a large diameter portion 5a and a small diameter portion 5b,
The whole is molded in a tubular shape. Also, the coil bobbin 1
A pair of metal pieces 6 serving as terminal pieces extending from the connector portion 4 to the bobbin portion 2 side are inserted into the inside of the. The tip 6a of the metal piece 6 has a recess 7 adjacent to the bobbin 2.
Is partially exposed on the surface of the wire, and the tip of the winding (not shown) is soldered. In addition, in the center hole 5,
Finally, a rod-shaped core made of a magnetic material is inserted.

By the way, when the coil bobbin 1 is injection-molded, in addition to the upper mold and the lower mold for molding the outer shape, as shown in FIG. 4 and FIG. The child mold 8 is required. Further, in this core mold 8, in order to support the metal piece 6 from the inside, two protrusions 9 along the longitudinal direction are formed on the surface thereof.

That is, the tip 6a of the metal piece 6 is formed by the above-mentioned ridge 9.
Is reliably pressed against the mold surfaces of the upper mold and the lower mold, and can be molded in an exposed state against the injection pressure.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, when the protrusion 9 for supporting a metal piece is provided on the surface of the core mold 8 as in the above-described conventional case, the large diameter portion 5a is formed on the inner periphery of the center hole 5 of the coil bobbin 1 formed. Groove over the entire length of
10 will be left. Since the groove 10 remains in the shape of a narrow passage even when the core (not shown) is incorporated in the center hole 5, it may lead to invasion of the external atmosphere and cause corrosion of the metal piece 6, for example.

In order to solve the problem, therefore, the present invention makes it possible to support only the exposed portion of the metal piece from the inside so that the above-mentioned concave groove does not remain. That is, this invention is a core mold for a metal core-equipped molded product in which a metal fragment is inserted in a state where the metal core is partially exposed on a part of the outer surface of a resin part having a cylindrical shape. Inside, a guide hole is formed along the longitudinal direction, the tip of the guide hole is opened at a position corresponding to the exposed portion of the metal piece, and a flexible metal piece supporting wire is provided in the guide hole. The feature is that it is slidably inserted.

Action The tip of the metal piece supporting wire moves forward and backward from the opening of the tip of the guide hole as it slides. Therefore, by exposing the metal piece supporting wire from the opening when setting the core type, the exposed portion of the metal piece is supported from the inside.

After molding the molded product in this state, by retracting the metal piece supporting wire, the core mold can be pulled out from the molded product. Therefore, only a slight recess corresponding to the tip of the metal piece supporting wire partially remains on the molded product side.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 The core mold 11 according to the present invention includes an upper mold 12 and a lower mold 13.
It is shown together with the molded product by these molds,
For example, the cavity 14 corresponding to the coil bobbin 1 described above.
Is defined.

The core mold 11 has a large diameter portion 15a as shown in FIG.
And a rod-shaped core main body 15 having a small diameter portion 15b as a main body, and the core main body 15 is linked with an angular pin (not shown) to advance and retreat with respect to the upper mold 12 and the lower mold 13 in the arrow A direction, that is, the axial direction. It is supposed to do.

A guide hole 16 is formed inside the core body 15 substantially along the axial direction thereof. This guide hole 16 is a core type
The tip end side of 11 is bent obliquely, and its tip end 16a is open to the side surface of the core body 15. Specifically, the metal piece 6 is opened at a position corresponding to the tip portion 6a, that is, the exposed portion. Two guide holes 16 are formed so as to correspond to the pair of metal pieces 6, respectively, but only one of them is shown.

A metal piece supporting wire 17 made of a metal wire such as a piano wire having flexibility is slidably inserted and arranged in the guide hole 16. This pair of metal piece support wires 17
The base end side of is linked to a drive mechanism such as an angular pin or an air cylinder (not shown).

 Next, the operation of the above configuration will be described.

First, with the metal piece 6 assembled in a predetermined position, the upper mold 12
The lower die 13 and the lower die 13 are clamped, and the core die 11 is set between them. And the metal piece supporting wire 17 of the core type 11
Is pressed in the protruding direction by an angular pin or the like.

As a result, the tip of the metal piece supporting wire 17 projects from the tip opening 16a of the guide hole 16, and the tip portion 6a of the metal piece 6 is pressed against the mold surface from the inside as shown in FIG.

In this state, the plasticized resin is injected into the cavity 14 to mold the coil bobbin 1. At this time, the metal piece 6
Since the tip portion 6a of the is indicated from the inside by the metal piece supporting wire 17, it can be inserted in an exposed state against the injection pressure. That is, it is possible to prevent the generation of defective products in which the tip portion 6a is covered with resin.

Further, when the mold is opened, the metal piece supporting wire 17 is retracted as shown in FIG. 2 before the core mold 11 is retracted, and then the core mold 11 is moved.
Is withdrawn, the upper mold 12 and the lower mold 13 are separated.
By retracting the metal piece support wire 17 as described above,
The core mold 11 can be pulled out without any problem.

Therefore, only a small recess corresponding to the tip of the metal piece supporting wire 17 remains in the final molded product, and the central hole 5
In the state where the core (not shown) is incorporated, it does not become a passage for the outside atmosphere to enter.

EFFECT OF THE INVENTION As is apparent from the above description, according to the core die for a molded product with a metal piece according to the present invention, since the metal piece is supported from the inside by the tip of the metal piece supporting wire, the metal piece is securely It can be exposed and inserted. Then, since the core die is pulled out from the molded product with the metal piece supporting wire retracted, only a small concave portion remains on the molded product side, and it is not necessary to form an unnecessary concave groove.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a core die according to the present invention together with an upper die, FIG. 2 is a sectional view showing only the core die, and FIG. 3 is formed by using a conventional core die. FIG. 4 is a cross-sectional view of the coil bobbin, FIG. 4 is a plan view of a conventional core type, and FIG.
It is sectional drawing which followed the V line. 1 ... Coil bobbin (molded product), 6 ... Metal piece, 11 ...
Core type, 15 ... Core body, 16 ... Guide hole, 17 ... Metal piece supporting wire.

Claims (1)

(57) [Scope of utility model registration request] 1. A core die for a metal piece with a metal piece, wherein a metal piece is inserted in a state where the metal piece is partially exposed on a part of an outer surface of a cylindrical resin portion, the inside of a rod-shaped core body. To
A guide hole is formed along the longitudinal direction, and its tip is opened at a position corresponding to the exposed portion of the metal piece,
A core die for a metal piece-attached molded product, characterized in that a flexible metal piece support wire is slidably inserted and arranged in the guide hole.