JPH0811156A - Mold for molding terminal of molding - Google Patents

Abstract

PURPOSE:To provide an economical mold simple in structure capable of molding the terminal of a molding in good appearance. CONSTITUTION:A mold for molding the terminal of a molding consists of a core mold 10 on which the bottom surface 32 of the terminal 31 of a molding main body is placed and a cavity mold 20 forming a terminal cap molding cavity 21 along with the core mold in adjacent relation to the terminal 31 of the molding main body so as to hold the terminal 31 between both molds 10, 20. Engaging members 11 of which the leading ends become the annular protruding parts 12 biting into the bottom surface of the terminal of the molding main body are provided to the inner surface 10a of the core mold 10 so that the annular protruding parts protrude from the inner surface of the core mold.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding die for molding a mall end.

[0002]

2. Description of the Related Art An automobile body is equipped with a plastic molding for decoration or for preventing damage to the vehicle body. In order to improve the efficiency of the molding operation, this molding is often used by extruding a plastic continuously in a predetermined cross-sectional shape and cutting it into a predetermined size according to the application.

However, the extrusion-molded product as cut has a drawback that the continuity of the molding is suddenly interrupted at the cut surface and the appearance becomes poor. Therefore, conventionally, as shown in FIG. 8, an end 41 of a molding body 40 obtained by cutting an extrusion-molded product into a predetermined length is arranged in a core mold 51 and sandwiched between the core mold 51 and the cavity mold 52. A molten resin is injected from a gate 55 into a cap-shaped cavity 53 formed adjacent to the terminal 53 to integrally form a terminal cap on the terminal 41. Reference numeral 54
Is a positioning pin of the mall body terminal.

However, in the injection molding die 50 composed of the core die 51 and the cavity die 52, the molding terminal may be retracted from a predetermined position due to the injection pressure of the molten resin. In particular, when the thickness of the molding body 40 becomes smaller than a preset reference thickness due to shrinkage after extrusion molding or the like, the cavity mold 52 is formed.
The sandwiching force between the core mold 51 and the core mold 51 becomes insufficient, and as shown in FIG. 9, the molding body 40 is easily retracted. In addition, the molten resin may penetrate into the gap between the surface of the molding body terminal 41 and the inner surface of the cavity mold 52 to make the joint line with the terminal cap look thick, or to form a burr at the joint line portion, resulting in poor appearance. was there.

Therefore, as disclosed in Japanese Utility Model Laid-Open No. 60-138721, there has been proposed an injection molding die in which a fixed core type supporting surface of a molding body is provided with a vertically adjustable position supporting die. However, in this mold, the mold structure was complicated and the cost was high.

[0006]

SUMMARY OF THE INVENTION The present invention has been proposed in order to solve the above problems, and it is possible to form a mall terminal with a good appearance and a simple mold structure. It is intended to provide an economical molding die for molding a mall terminal.

[0007]

That is, the present invention provides:
A molding die for molding a mall end including a core mold on which a bottom surface of a terminal of the molding body is placed and a cavity mold which forms a terminal cap molding cavity adjacent to the terminal with the terminal of the molding body interposed therebetween. In the core mold inner surface on which the terminal bottom surface of the molding body is placed, a locking member whose tip is an annular projection that bites into the molding body terminal bottom surface, and the annular projection part projects from the core molding surface. The present invention relates to a molding die for molding a molding terminal, which is characterized by being provided as described above.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a main part showing an example of a molding die for molding the present invention, FIG. 2 is a plan view of a core mold, FIG. 3 is a perspective view showing an example of a locking member, and FIG. FIG. 5 is a perspective view showing the proportionality of the locking member, FIG. 6 is a sectional view showing the other proportionality, and FIG. 7 is a sectional view showing another example of the locking member.

As shown in FIG. 1, the molding die for molding a molding of the present invention comprises a core mold 10 and a cavity mold 20, and a molding body 30 is extruded in advance and is cut into a predetermined size at a terminal 31 of a molding body 30. It is for molding the terminal cap.

The terminal bottom surface 32 of the molding body 30 is placed on the core mold 10. In this example, the core mold 10 is provided with an end positioning pin 16 for correctly setting the molding in the mold, and the end of the end of the molding main body 30 is placed in contact with the end positioning pin 16. To be done.

On the other hand, the cavity mold 20 is the core mold 1 described above.
The terminal cap molding cavity 21 is formed at the tip of the terminal 31 by sandwiching the terminal 31 of the molding body with 0. The terminal cap molding cavity 21 has a shape corresponding to the molding terminal cap to be molded, is formed adjacent to the tip of the terminal 31 of the molding body, and has one end communicating with the gate 22.

In the core mold 10, the terminal bottom surface 3
The mold inner surface 10a on the side on which 2 is mounted is provided with a locking member 11 for fixing the terminal position thereof.

The locking member 11 is for cutting into the bottom surface 32 of the molding body by clamping the core mold 10 and the cavity mold 20, and locking the molding body end in the mold to fix the position. The rod-shaped mounting hole 17 is provided in the inner surface 10a of the core mold and has a tip slightly protruding from the inner surface. In this embodiment, the locking member 11 has a diameter of about 6 mm and a length of about 10 m.
m is a screw member, and the core mold inner surface 10
It is screwed to a. Reference numeral 18 is a screw thread provided on the outer peripheral surface of the locking member.

An annular projection 12 is provided at the tip of the locking member 11. The annular protrusion 12 is for making it easier for the locking member 11 to bite into the terminal bottom surface 32 of the molding body and for ensuring the locking. In this example, as shown in FIG. 3, by forming the inner peripheral surface of the hexagonal shape, the head of a wrench or the like is inserted and the locking member 11 is rotated, so that the protrusion height from the core mold 10 is increased. Can be adjusted appropriately. Inner surface 10 of the core die 10 of the annular protrusion 12
The protrusion height from a is appropriately adjusted according to the hardness of the molding body 30 and the like, and is appropriately about 0.1 to 0.2 mm.

Height of the annular projection 12 (depth of the inner surface)
Can be appropriately determined according to the hardness of the molding body 30, but if the molding is too shallow, it may not sufficiently bite into the bottom surface 32 of the molding body, resulting in insufficient position fixing. It is preferably 1 mm or more, and particularly preferably 3 mm or more. In this example, it is about 4 mm. Further, in order to increase the pressing area against the bottom surface of the molding body 30, it is convenient that the inner diameter of the ring of the annular projection 12 is as large as possible.
It is preferably about 2 mm or more. Further, the annular protrusion 1
If the thickness of the ring 2 is too thin, it may damage the bottom of the molding, and if it is thick, it will be difficult to bite into the bottom of the molding. In this embodiment, it is about 1 mm.

The number of the locking screw members 11 can be appropriately determined according to the thickness and hardness of the molding body, but it is desirable to provide a plurality of them, and in this example, four. Further, as shown in FIG. 2, by arranging them in two rows, the mall body terminal can be held more firmly. In addition,
Although illustration is omitted, if a preliminary locking member is arranged in the mounting hole 17 of the core mold 10 and the locking member 11 is supported from below, the locking member 11 is effectively prevented from loosening. Target.

Next, a method for manufacturing a molding terminal using the mold of the present invention will be briefly described. First, the protrusion height of the locking screw member 11 from the inner surface 10a of the core is adjusted, and the tip of the molding main body terminal 31 is placed in contact with the terminal positioning pin 16 and placed on the inner surface of the core mold 10. Then, the cavity mold 20 is clamped, and the molten resin is injected into the terminal cap molding cavity 21 via the gate 22. At that time, as is better understood from FIG. 4, the mall body terminal 31
Since the annular projection 12 of the locking member 11 bites into the bottom surface 32, the position of the molding body 30 in the mold is securely fixed, and the molding body 30 does not retract even by the injection pressure of the molten resin. Therefore, since the end cap molding cavity 21 does not become large due to the retreat of the molding body terminal 31 and a gap is not formed between the surface of the molding body terminal 31 and the inner surface of the cavity mold 20, the molten resin has the original size. The terminal cap molding cavity 21 is filled, and the terminal cap is integrally formed on the molding body terminal 31 without forming burrs or the like.

When the molding body has a thickness smaller than the reference, the locking member 11 is rotated to further project the annular projection 12 from the core mold inner surface 10a. As a result, the annular protrusion 12 of the locking member 11 bites into the bottom surface of the end of the molding body, and the terminal of the molding body is pressed against the inner surface of the cavity mold 20, so that the molding body moves backward due to the injection pressure of the molten resin, or the molding body moves backward. It is possible to prevent burrs from being generated between the terminal surface of the main body and the terminal cap.

Moreover, according to the present invention, the structure of the mold is extremely simple, and there is an advantage that it can be applied to an existing mold. Furthermore, it is very convenient because it does not take time and effort to adjust the protrusion of the locking member and perform maintenance. Immediately after molding, the molding is formed with a recess due to an annular projection on the back surface, but the resin that forms the molding body restores quickly to its original shape, which hinders assembly of the vehicle body. Absent.

FIGS. 5 and 6 show the comparison of the locking members. The locking member 25 shown in FIG. 5 has a sharp tip 26. With such a shape, the pressing area against the bottom surface of the molding body is small, and a good molding locking effect cannot be obtained. Further, since the tip 26 is stuck in the bottom surface of the molding, a hole remains on the bottom surface of the end of the molding body after molding, which is a design problem. FIG. 6 shows the annular protrusion 27.
In this example, the tip 28 has a tapered shape and the inner surface of the annular projection 27 is formed to have a shallow depth. Even in this example, since the pressing area against the bottom surface of the molding body is reduced, the molding body tends to shift with respect to the injection pressure in the lateral direction (longitudinal direction of the molding body), which is not effective.

FIG. 7 shows another example of the locking member. The locking member 33 is in the shape of a rod having a screw portion 34 on the lower side, and has a thin step portion 38 provided on the inner surface of the core die 39.
The annular projection 36 at the tip end is inserted into the recess 35 having the shape. The locking member 33 is provided with a proper number of shims 37 fitted on the screw portion 34 and arranged between the step portion 38 and the locking member 33, so that the protruding height of the annular projection 36 from the inner surface of the core die 39 is increased. Can be adjusted. Reference numeral 34a denotes a nut, which is screwed to the screw portion 34 from the lower side of the core mold 39 to fix the locking member 33.

[0022]

As shown and described above, according to the molding die for molding a molding of the present invention, not only when the thickness of the molding body is the reference thickness, but also when the molding body is thin,
It is possible to prevent the molding body from retracting due to the injection pressure of the molten resin when molding the terminal cap. Therefore, without causing burr or defective shape of the joint surface,
The terminal cap can be accurately formed on the terminal of the molding body with good appearance. Moreover, the structure of the mold is simple and easy to adjust, and the cost for manufacturing the mold can be kept low.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part showing an example of a molding die for molding a terminal of the present invention.

FIG. 2 is a plan view of a core type.

FIG. 3 is a perspective view showing an example of a locking member.

FIG. 4 is a cross-sectional view showing the operation of the molding die for molding a molding of the present invention.

FIG. 5 is a perspective view showing a relative proportion of a locking member.

FIG. 6 is a cross-sectional view showing other contrasts.

FIG. 7 is a cross-sectional view showing another example of a locking member.

FIG. 8 is a sectional view showing an example of a conventional molding die for molding a terminal.

FIG. 9 is a cross-sectional view showing a molding example of the molding terminal by the mold.

[Explanation of symbols]

 10 Core Type 11 Locking Member 12 Annular Projection 20 Cavity Type 21 End Cap Molding Cavity 22 Gate 30 Mall Main Body 31 Terminal 32 Bottom Bottom Surface of Mall Main Body

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display area B29K 105: 20 B29L 31:30

Claims (2)

[Claims] 1. A core mold on which the bottom surface of the end of the molding body is placed, and a cavity mold for sandwiching the molding body end between the core mold and a terminal cap molding cavity adjacent to the molding die. In the molding die for molding a terminal, on the inner surface of the core die on which the terminal bottom surface of the molding body is placed,
A molding die for molding a molding terminal, characterized in that a locking member having an annular projection having a tip that digs into the bottom surface of the molding body terminal is provided such that the annular projection projects from the inner surface of the core mold. 2. The molding die for terminal molding according to claim 1, wherein the locking member is a screw member and is screwed to the inner surface of the core mold.