JP3840305B2 - Insert mold - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mold for insert molding.
[0002]
[Prior art]
As an insert molded product, as shown in FIG. 3, there is a resin mold key in which a handle portion 2 made of a synthetic resin is integrally formed on a handle portion of a metal key plate 1. In the production of this resin mold key, a mold composed of a pair of mold plates facing each other in the thickness direction so as to be sandwiched from both sides of the key plate 1 is usually used. A gate is provided at the mold dividing part on the opposite side and a molten resin is injected into the cavity from the direction indicated by arrow C in FIG. 3 (side gate), or a gate is provided on the movable side mold plate. A system (pin gate) for injecting molten resin from the direction indicated by arrow D is adopted.
[0003]
[Problems to be solved by the invention]
However, in the gate structure as described above, the key plate 1, a fixing pin provided in a direction orthogonal to the key plate 1 in order to hold and fix the key plate at a predetermined position of the cavity, and the key holder mounting hole 3 Since the molten resin flow is divided by the male mold for forming the resin flow and the divided resin flow collides with the downstream side, the generation of the weld line 18 is inevitable. In the resin mold key shown in FIG. 3, since the emblem panel 4 is embedded in the concave portion 5 formed in the center portion of the grip portion 2, the weld line 18 generated in the concave portion 5 is not actually a problem. If 18 reaches the outer peripheral part of the holding part 2, the weld line 4 will be exposed and the appearance will deteriorate.
[0004]
The present invention has been devised for the purpose of providing an insert molding die configured to solve such problems of the prior art and to form a weld line in an inconspicuous manner. .
[0005]
[Means for Solving the Problems]
In order to achieve such an object, in the present invention, a fixed mold plate (8a) and a movable mold plate ( 8a) facing each other in the plate thickness direction of a metal plate-like insert material (the handle portion 1a of the key plate 1 ) ( 8b) In an insert molding die provided with a gate for injecting resin around the insert material on one side of the insert material, two gates (12, 13) are adjacent to each other so as to face one surface of the insert material. Established and opened one of these two gates (first gate 12) at the center of the protrusion (16) in close contact with the opening peripheral edge of the hole (through hole 15) penetrating the insert material in the plate thickness direction. The molten resin injected from the one gate and flowing into the cavity (A) on the other surface side of the insert material through the hole, and the one side cavity (B) injected from the other gate (second gate 13) ) Fusion and the resin was assumed that as spread substantially symmetrically from positions close to each other in each cavity of one surface and the other surface side, meet at parting surface of the fixed die plate and the movable die plate.
[0006]
According to this, the weld line is formed so as to overlap the parting line, and an insert molded product in which the weld line is not conspicuous can be manufactured. Moreover, since the two gates can share the runner, the structure is not complicated.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the configuration of the present invention will be described in detail based on embodiments shown in the accompanying drawings.
[0008]
FIG. 1 shows an insert molding die constructed according to the present invention. This mold has a grip portion 2 made of synthetic resin integrally formed with the handle portion of the key plate 1 shown in FIG. 3, and has a recess 5 in which the key holder mounting hole 3 and the emblem panel 4 are embedded. It is used for manufacturing a resin mold key, and includes a pair of fixed and movable mold plates 8a and 8b facing each other in the thickness direction of the handle portion 1a of the key plate 1.
[0009]
Both the fixed and movable mold plates 8a and 8b are provided with fixing pins 9a and 9b for supporting and fixing the handle 1a of the key plate 1 at a predetermined position in the cavity, one by one. Thus, the handle portion 1a of the key plate 1 is sandwiched with a required tightening force.
[0010]
Further, male molds 10a and 10b for forming the key holder mounting hole 3 are provided on both mold plates 8a and 8b so as to be able to abut each other. Further, male molds 11a and 11b for projecting the recesses 5 for embedding the emblem panel project from both the mold plates 8a and 8b.
[0011]
As shown in FIG. 2, the movable mold 8 b is opened side by side in the axial direction of the key plate 1 in such a manner that the first and second gates 12 and 13 share the runner 14. . The first gate 12 is provided at a position corresponding to the through-hole 15 previously opened in the handle 1 a of the key plate 1, and from the end face of the mold 11 b so as to be in close contact with the opening peripheral edge of the through-hole 15. The first gate 12 is opened at the center of the protruding protrusion 16 formed. The second gate 13 is opened at the end face of the male die 11b.
[0012]
The molten resin injected from the first gate 12 passes through the through hole 15 of the key plate 1, flows into the cavity A between the fixed mold plate 8 a and the key plate 1, and spreads radially there. On the other hand, the molten resin injected from the second gate 13 flows into the cavity B between the movable mold plate 8b and the key plate 1 and spreads radially there. The resin spread over the entire front and back surfaces of the key plate 1 meets at the abutting surfaces of both mold plates 8a and 8b. Therefore, a weld line is formed so as to overlap the parting line 17 shown in FIG.
[0013]
【The invention's effect】
As described above, according to the present invention, since the weld line is formed so as to overlap the parting line, the weld line is not conspicuous, and a great effect can be obtained in improving the merchantability of the insert molded product.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a mold for insert molding according to the present invention.
2 is a front view of the movable mold plate shown in FIG. 1. FIG.
FIG. 3 is a perspective view showing a resin mold key.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Key plate 1a Handle | pattern part, 1b Shaft part 2 Grasping part 3 Key holder attachment hole 4 Emblem panel 5 Recessed part 8a Fixed type | mold board 8b Movable type | mold board 9a * 9b Fixing pin 10a * 10b Male model (for forming a key holder attachment hole) 11a, 11b Male mold 12 (for forming a recess for embedding the emblem panel) First gate 13 Second gate 14 Runner 15 Through hole 16 Projection 17 Parting line 18 Weld line

Claims (1)

An insert molding die in which a gate for injecting resin around the insert material is provided on one of a fixed mold plate and a movable mold plate facing each other in the plate thickness direction of a metal flat insert material. There,
The gate is two gates opened adjacent to each other so as to face one surface of the insert material, and one of the two gates is an opening peripheral edge of a hole penetrating in the thickness direction of the insert material Opened at the center of the protrusion closely contacting the part, molten resin injected from one of the gates and flowing into the cavity on the other surface side of the insert material through the hole, and one surface side injected from the other gate The molten resin that has flowed into the cavities of the first and second surfaces spread substantially symmetrically from the positions adjacent to each other and meet at the parting surfaces of the fixed mold plate and the movable mold plate. A mold for insert molding characterized by the above.

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