JP2001129857A - Injection mold of plastic material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection mold of plastic material capable of making the shape and dimensional accuracy of a pawl part constant and capable of sufficiently ensuring the fitting quantity of the pawl part and a partner part. SOLUTION: In an injection mold of a plastic material for forming a molded article 13 having a pawl part 14 protruded against the opening direction of a fixed mold 11 and a movable mold 12, one set of slide molds 19a, 19b performing opening operation so as to be separated from each other in a direction different from the opening direction of the fixed and movable molds 11, 12 are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic injection mold, and more particularly, to a plastic injection mold for molding a molded product having a hook having a hooking function.

[0002]

2. Description of the Related Art Conventionally, there has been known a plastic injection mold for forming a nail-shaped molded product (product) having a hooking function. A claw having a hooking function in only one direction is protruded from the tip of the molded product formed in the plastic injection mold.

FIG. 4 is an enlarged partial explanatory view of a claw forming portion of a conventional plastic injection mold. As shown in FIG. 4, a shaft (ejector pin) 3 is rotatably supported on an ejection plate 1 provided in a plastic injection mold via an anchor pin 2.

[0006] At the tip of the shaft 3, a claw portion 3 a for forming the claw portion 5 of the molded product 4 is formed. The claw portion 5 is provided so as to protrude from the flat portion 4a of the molded product 4, and has a hooking function in only one direction at the tip.

When the molded product 4 is taken out of the mold, the molded product 4 is protruded from the die. At this time, the protruding plate 1 is protruded in the extension direction of the shaft 3 (see the arrow a in the figure). As a result, the shaft 3 disposed at an angle of θ with respect to the molded product 4 moves the claw portion forming portion 3a in the hook forming direction (see the arrow b in the drawing), and the claw portion forming portion 3a
From the claw portion 5.

By the way, in order to provide the hook 5 with a hooking function in two opposite directions, the hook 5 is located on both sides of the tip of the hook 5, and
It is necessary to provide a hook at the point.
With the same configuration as that having the hooking function only in the direction, it was not possible to provide two shafts 3 corresponding to the two hooking portions to cope with the problem. This is because, when two shafts 3 are arranged on both sides of the claw portion 5, the shafts 3 having the respective thicknesses interfere with each other, and the shaft 3 cannot be moved in two directions.

[0007] Therefore, the present invention has been applied to a case where a hooking function in two opposite directions is provided by forcible projection.

FIG. 5 is an enlarged partial explanatory view of a claw forming portion of a conventional plastic injection mold having a hooking function in two opposite directions. As shown in FIG. 5, in the case of a conventional plastic injection mold having a hooking function in two opposite directions, a pair of shafts (ejector pins) 6, 6 are rotatably supported in place of the shaft 3. Have been. At the tip of each shaft 6, a claw forming portion 6a for forming a claw 7 having two hooks is formed.

When the molded product 4 is taken out from the mold in such a configuration, the molded product 4 is protruded (see the arrow a in the figure), and the claws 7 forcibly hold the shafts 6 on both sides. Push and spread (see arrow b in the figure), claw 7
Was forcibly released from the claw portion forming portion 6a (forced protrusion).

[0010]

However, since the pair of shafts 6, 6 in which the claw portion 7 itself is not opened is forcibly pushed open by the forced protrusion, the claw portion 7 is scratched or the resin is scraped. The nail part 7
It has been difficult to make the shape and dimensional accuracy of the film constant.
Further, in order to perform the forced protrusion, the hooking amount of the claw portion 7 cannot be made large, and the fitting amount between the claw portion 7 and the mating component cannot be sufficiently secured.

An object of the present invention is to provide a plastic injection mold capable of keeping the shape and dimensional accuracy of the claw portion constant and ensuring a sufficient amount of fitting between the claw portion and a mating part. It is.

[0012]

In order to achieve the above object, a plastic injection mold according to the present invention is provided with a protruding portion which protrudes against the opening directions of a fixed mold and a movable mold. In a plastic injection mold for forming a molded product provided, a set of slide dies that perform opening operations so as to be separated from each other in a direction different from an opening direction of the fixed mold and the movable mold. It is characterized by having.

[0013] With the above structure, the plastic injection mold is a set of slide dies which perform opening operations so as to separate from each other in a direction different from the opening direction of the fixed mold and the movable mold. A molded product having a protruding portion formed so as to oppose the opening direction of the fixed mold and the movable mold is formed by the mold. Thereby, the shape and the dimensional accuracy of the protruding portion can be made constant, and the fitting amount between the protruding portion and the mating component can be sufficiently ensured.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic view of a plastic injection mold according to an embodiment of the present invention. As shown in FIG. 1, the plastic injection mold 10 has a fixed side (cavity) 11 and a movable side (core) 12, and is fixed when the plastic injection mold 10 is closed (see FIG. 1). A space is formed between the side 11 and the movable side 12. A resin is injected into this space to form a molded product (product) 13. The plastic injection mold 10 has a fixed side 11 and a movable side 12.
Move away from each other (in the vertical direction in the figure) and become open.

FIGS. 2A and 2B show the opened state of the plastic injection mold of FIG. 1, wherein FIG. 2A is a partially enlarged view and FIG. 2B is an explanatory view of the upper protruding plate viewed from the lower surface side. FIG.
FIG. 3 is a partially enlarged view of the plastic injection mold of FIG.

As shown in FIG. 2A, a molded product 13 formed in a plastic injection mold 10 has a flat surface 13.
c (protruding portion) 14 protruding in a direction substantially perpendicular to a
And two locking end portions 15 having hooking functions in two opposite directions are formed on both sides of the tip of the claw portion 14. The two locking end portions 15 have a shape in which the protruding end is cut off at an acute angle, so that a sufficient amount of fitting between the claw portion 14 and the mating component can be ensured.

That is, the claw portion 14 provided on the molded product 13
By having the locking end 15, when molding with the plastic injection mold 10, the mold on the fixed side 11 and the movable side 12
Has a shape protruding against the opening direction of the mold.

The plastic injection mold 10 has a protruding pin 16 for extruding and releasing the molded article 13 after molding, and a protruding plate 17 for moving the protruding pin 16. The protruding plate 17 includes an upper protruding plate 17a and a lower protruding plate 17b, which are stacked on each other. Two sliding spaces 1 penetrating to the surface side of the upper protruding plate 17a are provided at the boundary between the two protruding plates 17a and 17b.
8a and 18b are formed.

The two sliding spaces 18a and 18b are arranged so as to be separated from each other in the direction in which the locking end 15 protrudes, and also in a direction substantially perpendicular to the direction in which the protruding end protrudes (FIG. 2). (B)).

The plastic injection mold 10 is
A pair of slide dies 1 forming the claw portions 14 of the molded product 13
9a and 19b (see FIG. 2A). With the pair of slide dies 19a and 19b closed, resin is injected into the space formed between the two slide dies 19a and 19b, so that the claw portion 14 having two locking end portions 15 is provided. Is formed.

The upper ends of the shafts 20a, 20b are connected to the outer sides of the lower ends of the slide dies 19a, 19b. After the shafts 20a and 20b cross each other, the lower ends of the shafts 20a and 20b have respective slide spaces 18a and 20b.
18b, each lower end can move in each slide space 18a, 18b via bearings 21a, 21b attached to each lower end.

The lower ends of the shafts 20a and 20b are moved in the protruding direction of the protruding plate 17 (see the arrow c in FIG. 2A) so that the sliding spaces 18a and 1b are moved.
8b are moved away from each other (see arrow d in FIG. 2A). The movement of the lower ends of the shafts 20a and 20b moves the slide dies 19a and 19b in directions away from each other (see the arrow e in FIG. 2A).
The two slide dies 19a and 19b are opened.

The movement of each shaft 20a, 20b at this time is such that each of the sliding spaces 18a, 18b has at least each shaft 20a in a direction substantially orthogonal to the movement locus of each lower end.
a, 20b are arranged in parallel with a separation between them (FIG. 2 (b)
Reference), since the movement trajectories of the lower ends are not on the same line, they do not interfere with each other.

That is, a pair of slide dies 19a, 19b
Performs an opening operation by a pair of shafts 20a and 20b moving on different trajectories without interfering with each other,
The pair of shafts 20a and 20b has an upper end connected to a pair of slide dies 19a and 19b, and a lower end formed with a protruding plate 17 that performs a protruding operation when the molded product 13 is released from the mold.
Is mounted so as to interlock with the movement of the protruding plate 17. Further, the protruding plate 17 is connected to each shaft 20.
The slide spaces 18a and 18b are arranged in such a manner that the shafts 20a and 20b are arranged side by side in a direction substantially orthogonal to the movement trajectory of the lower ends of the shafts 20a and 20b.

Next, the operation of the plastic injection mold 10 will be described. First, the plastic injection mold 10 is closed, and a resin is injected into a space formed between the fixed side 11 and the movable side 12. Thereafter, the fixed side 11 and the movable side 12 are opened, and the molded product 13 is taken out.

At this time, the plastic injection mold 10
In the open state, the extruding plate 1 is used to push out the molded product 13.
7 moves. With the movement of the protruding plate 17, the protruding pin 16 is protruded, and the shafts 20a, 20
The lower end of Ob moves so as to separate the slide spaces 18a and 18b from each other.

As the lower ends of the shafts 20a and 20b move on different trajectories without interfering with each other, the slide dies 19a and 19b connected via the shafts 20a and 20b are opened. State. The movement of each of the slide dies 19a and 19b is performed along the protruding end protruding direction of the locking end 15 (see the arrow b in the drawing).
The claw portion 14 is not scratched or the resin is not sharpened, which occurs in the case of the forced protrusion.

By this protruding operation, the slide dies 19a and 19b are completely separated from the claw portion 14 and the molded product 13
Can be taken out of the plastic injection mold 10. In addition, since it is not necessary to perform the forced protrusion, the hooking amount of the claw portion 14 can be increased, and the fitting amount between the claw portion 14 and the mating component can be sufficiently ensured.

In particular, the plastic injection mold 10 is
Since the molded product 13 is released after the slide dies 19a and 19b are completely separated from the claw portion 14, it is possible to form even the claw portion 14 having a shape with a large amount of hooking of the locking end portion 15. .

Therefore, when molding the molded article 13 provided with the claw portion 14 having a hooking function, the fixed side (cavity) 11 and the movable side (core) 12 of the plastic injection mold 10 are formed.
The two slide dies 19a and 19b must be moved so as to be separated from each other in one direction (x direction or z direction) substantially orthogonal to the opening direction (this is referred to as the y direction). By preventing the shafts 20a and 20b from interfering with each other on the extension of the movement trajectory, the movement of the slide dies 19a and 19b is ensured, and the claw portion 14 is secured.
Need not be forcibly released from the mold.

As described above, according to the present invention, even if the molded product 13 has the claw portions 14 in which the pair of slide dies 19a and 19b need to move in different directions, the slide dies are not forced out. It can be released from the mold. As a result, the claw portion 14 is not scratched and the resin is not sharpened, so that the shape and dimensional accuracy of the claw portion 14 can be made constant. In addition, since the locking end 15 has no restriction on the amount of protrusion and the shape, the claw 1
4 can be sufficiently secured with the mating part which is hooked.

In the above embodiment, the claws 14
May be provided not only at two places but also at a plurality of places.
The projecting direction of the projecting end of 5 may also be a direction substantially orthogonal to the direction in which the fixed side 11 and the movable side 12 open. If formed in such a direction, the movement of the protruding plate 17
Each shaft 20a, 20b for opening the slide mold
The moving direction in the sliding spaces 18a and 18b may be matched with the protruding direction of the protruding end of the locking end 15.

[0034]

As described above, according to the present invention, the plastic injection mold is opened so as to separate from each other in a direction different from the opening direction of the fixed mold and the movable mold. By using a set of slide molds, a molded product is formed with a protrusion that protrudes against the opening direction of the fixed mold and the movable mold, so that the shape and dimensional accuracy of the protrusion are reduced. In addition to being constant, a sufficient amount of fitting between the projecting portion and the mating component can be ensured.

[Brief description of the drawings]

FIG. 1 is a schematic view of a plastic injection mold according to an embodiment of the present invention.

FIGS. 2A and 2B show an open state of the plastic injection mold of FIG. 1, wherein FIG. 2A is a partially enlarged view, and FIG. 2B is an explanatory view of an upper protruding plate viewed from a lower surface side.

FIG. 3 is a partially enlarged view of the plastic injection mold of FIG. 1 in a protruding state.

FIG. 4 is an enlarged partial explanatory view of a claw forming portion of a conventional plastic injection mold.

FIG. 5 is an enlarged partial explanatory view of a claw forming portion of a conventional plastic injection mold having a hooking function in two opposite directions.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Plastic injection mold 11 Fixed side 12 Movable side 13 Molded product 13a Flat surface 14 Claw 15 Locking end 16 Protruding pin 17 Protruding plate 17a Upper protruding plate 17b Lower protruding plate 18a, 18b Slide space 19a, 19b Slide metal Mold 20a, 20b Shaft 21a, 21b Bearing

Claims (6)

[Claims] 1. A plastic injection mold for forming a molded product provided with a protruding portion protruding against the opening direction of a fixed mold and a movable mold, wherein the fixed mold and the movable mold are provided. A plastic injection mold having a pair of slide molds that perform an opening operation so as to separate from each other in a direction different from an opening direction of a side mold. 2. The projection according to claim 1, wherein the projection is provided on a flat surface of the molded product, and has a plurality of locking ends having hooking functions in opposite directions on both sides of the tip.
2. The plastic injection mold according to 1. 3. The locking end portion has a protruding amount and a shape capable of sufficiently securing a fitting amount with a mating part which is hooked with the protruding portion. Item 3. A plastic injection mold according to Item 2. 4. The apparatus according to claim 1, wherein the pair of slide dies perform an opening operation by a pair of shafts moving on different trajectories without interfering with each other. The described plastic injection mold. 5. The set of shafts has an upper end connected to the set of slide dies, and a lower end provided with a protruding plate for performing a protruding operation when the molded product is released from the mold. The plastic injection mold according to claim 4, wherein the plastic injection mold is attached so as to be linked to the movement. 6. The projecting plate according to claim 5, wherein the protruding plate has a slide space in which the shafts are arranged in parallel at a distance in a direction substantially perpendicular to the movement locus of the lower end of each shaft. Plastic injection mold.