JP2000202859A - Injection molding die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a damage of a fine pine and to manufacture stable injection moldings in a mass production by vertically movably support an ADP plate of a CAV plate, and inserting the pin mounted at its end at the ADP plate into an insertion hole of a COR plate after mold is completely closed. SOLUTION: An insertion hole 10 of an ADP late 1 and a guide bush 4 of a CAV plate 2 are inserted into a guide pin 5 mounted at a COR plate 3, and the plate 2 is mounted on the plate 3 while positioning the pin 5 and the bush 4. The plate 1 and the plate 2 are closed therebetween against a spring 9, a fine pin 7 mounted at the plate 1 is inserted into an insertion hole 8 of the plate 3, and the pin 7 is inserted into the hole 8 when a molding machine is completely closed. Thus, the pin 7 is engaged with upper and lower molds without damaging it due to a mold deviation, and a strength of the pin 7 is obtained to prevent its damage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection mold for an injection-molded article having micropores,
The present invention relates to an injection mold capable of preventing breakage of a small-diameter pin used for forming a fine hole and enabling stable mass production.

[0002]

2. Description of the Related Art A conventional injection mold will be described.
FIG. 4 shows the structure of a conventional general injection molding die, in which 11 is a CAV plate, and 12 is a COR.
Plate, 13 is a guide bush, 14 is a guide pin, 1
5 is a fine pin for forming a hole, 16 is a taper guide, and 17 is a pin insertion hole provided in the CAV plate 11.

[0003] When molding an injection-molded article having fine holes with a conventional injection mold having the above structure, the fine pins 15 for forming the fine holes are required to secure strength and prevent breakage. After the pin 15 is inserted into an insertion hole 17 that is often provided with a CAV plate 11 which is a counterpart corresponding to the position of the pin and is slightly larger than the diameter of the pin, molding is performed.

The fine pin 15 is held by a hole provided on the COR plate 12 side and an insertion hole 17 provided on the CAV plate 11 side by a processing method using vertical cutting by insertion of the pin. With the two-point support, the processing is performed while preventing the fine pin 15 from falling or being broken, so that stable molding can be performed. Insertion hole 1 in this case
The diameter of 7 is slightly larger than the diameter of the fine pin 15 to prevent burrs.

[0005]

However, when a molded product is formed by vertical cutting of a conventional apparatus, the following problems occur. First, as a feature of a general molding die as shown in FIG. 4, a CAV plate 11 and a CV plate 11 are used in order to reduce the pitch deviation of the die caused by the expansion of the die due to the die temperature.
Guide pin 14 to be inserted into OR plate 12 and CAV
Between the guide bush 13 provided on the plate 11 and 1
A gap of about 0 to 20 μm is provided.

After the positioning is performed to some extent by the guide pins 14 and the guide bush 13, the final positioning is completed by the taper guide 16 when the mold is closed. Further, in order to prevent the occurrence of burrs in the injection molded product, the clearance between the diameter of the fine pin 15 and the diameter of the insertion hole 17 is generally smaller than the gap of the guide pin.

Here, a fine pin 15 for vertical cutting is used.
Must be already inserted into the insertion hole 17 before the mold closing is completed. However, the final positioning cannot be ensured unless the taper guide 16 is used at the time of closing the mold. Therefore, at the time of insertion of the fine pin 15, a gap is generated in the pitch between the pin and the hole, and the pin may not be inserted properly. .

Therefore, conventionally, there is a high possibility that the fine pin 15 falls down or is broken due to a pitch shift between the fine pin 15 and the insertion hole 17, and the tendency is more remarkable as the diameter of the pin becomes smaller. Further, when a large number of micropores are provided, the releasability at the time of removing the molded product is poor, and there is a possibility that the molded product may be deformed at the time of removal. The present invention has been made to solve the above problems, and after the mold closing is completed and the positions of the upper and lower molds are accurately determined, the breakage of the pins is prevented by inserting the fine pins 15 into the insertion holes 17. It is intended to enable stable mass production of injection molded products.

[0009]

In order to solve this problem, an injection mold of the present invention comprises a CAV plate, a COV plate and a COV plate.
An R plate, a guide pin inserted into an insertion hole of the CAV plate and the COR plate, and a CAV plate and the COR.
In an injection mold equipped with a taper guide for positioning the plate and a fine pin inserted into the insertion hole of the COR plate from the CAV plate side, the upper part of the CAV plate is supported so as to be vertically movable while being separated from the CAV plate. An ADP plate is provided, and the ends of the fine pins are attached to the ADP plate.
An injection molding die characterized in that it is held so as not to protrude downward from a part surface of a V plate, and is inserted into an insertion hole of a COR plate after the mold is completely closed. In the present invention, not before the mold closing is completed, but after the mold closing in which the pitch of the CAV and COR molds exactly coincides with each other, the fine pin is penetrated into the insertion hole to prevent breakage of the pin. It becomes possible.

As a result, breakage of the pin when the mold is closed is greatly reduced, and the effect of improving the strength of the fine pin by two-point support is also obtained. Furthermore, when the mold is opened, the part surface opens after the fine pin is completely retracted from the insertion hole or molded product, and the pin is removed in the mold before opening the mold, so the molding that occurs at the time of mold release This prevents deformation of the product and secures stable mass production.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention positions a CAV plate, a COR plate, a guide pin inserted into an insertion hole of the CAV plate and the COR plate, and positions the CAV plate and the COR plate. In an injection mold having a taper guide and a fine pin inserted into the insertion hole of the COR plate from the CAV plate side, an ADP plate supported on the upper portion of the CAV plate so as to be vertically movable while being separated from the CAV plate. The end of the fine pin is attached to the ADP plate, and the tip of the fine pin is always held so as not to protrude downward from the part surface of the CAV plate.
It is characterized by being inserted into the insertion hole of the plate. After the part surface is closed and the pitch of both the CAV and COR molds is exactly matched, the fine pin is inserted into the insertion hole of the COR plate. Insertion greatly reduces pin breakage, ensures pitch accuracy while preventing pitch shift, and removes fine pins from inside the mold before opening both dies, thus releasing the mold. This has the effect of preventing the deformation of the molded product, which is sometimes caused, and securing a stable mass-produced product.

According to a second aspect of the present invention, the ADP plate is supported above the CAV plate via a guide pin and a spring member. In addition, a simple member configuration can prevent the breakage of the fine pin, and can prevent the deformation of the product when removing the molded product. Hereinafter, embodiments of the present invention will be described with reference to the drawings. (Embodiment) FIGS. 1, 2 and 3 are sectional views showing an injection mold according to the present invention. In the figure, 1 is an ADP plate, 2 is a CAV plate, 3 is a COR plate, 4 is a guide bush, 5 is a guide pin mounted on the COR plate 3, 6 is a taper guide for positioning, and 7 is fixed to the ADP plate. Reference numeral 8 denotes a fine pin for forming a hole, 8 denotes an insertion hole for the fine pin provided in the COR plate 3, and 9 denotes a spring mounted between the ADP plate 1 and the CAV plate 2.

The closing operation of the injection mold of the present invention will be described. First, as shown in FIG.
The insertion hole 10 of the ADP plate 1 and the guide bush 4 of the CAV plate 2 are inserted into the guide pins 5 mounted on the COR plate 3, and as shown in FIG.
Is positioned by the guide pin 5 and the guide bush 4, and the CAV plate 2 is mounted on the COR plate 3;
The part surfaces of the CAV plate 2 and the COR plate 3 are abutted. At this time, the ADP plate 1 and the CAV plate 2 are separated by the action of the spring 9, and the tips of the fine pins 7 fixed to the ADP plate 1 do not protrude from the surface of the CAV plate 2.

As shown in FIG. 2, CAV plates 2 and C
When the part surfaces of the OR plate 3 are matched, the COR
The taper guide 6 attached to the plate 3 is fitted to the taper guide 6a attached to the CAV plate 2, the pitch of the CAV plate 2 and the pitch of the COR plate 3 are completely matched, and accurate positioning of the upper and lower dies is performed. At this time, the ADP plate 1 and the CAV plate 2 are still separated by the spring 9, and the fine pins are not inserted into the insertion holes 8 of the COR plate 3.

Next, when the space between the ADP plate 1 and the CAV plate 2 is closed against the spring 9, the fine pins 7 are gradually inserted into the insertion holes 8 of the COR plate 3, and as shown in FIG. Is completely closed, the fine pin 7 is fitted in a state penetrating the insertion hole 8 on the COR plate 3 side. In this state, the resin is injected into the cavity.

When the mold is opened after injection molding, the mold is opened in the reverse order of closing. That is, when the opening of the mold of the molding machine is started, the fine pin 7 is first lifted up by the spring 9, so that the pin 7 is extracted from the insertion hole 8 on the COR 3 side and the molded product. After the pin 7 is completely removed from the insertion hole 8 and the molded product, the part surfaces of the CAV plate and the COR plate are opened, and the molded product is removed.

In the above embodiment, an example in which the present invention is applied to an injection molding die has been described. However, the present invention can be similarly applied to other processing equipment having pins that require high pitch accuracy. The arrangement of pins, guides, etc. used in this mold is shown in FIG.
The present invention is not limited to a few CAV sides and COR sides, but can be similarly carried out even if the mounting direction and the mounting plate are changed depending on the product shape and molding machine specifications.

This embodiment shows an example in which the present invention is used in a component for adjusting a gas flow rate of a gas appliance.

[0019]

As described above, according to the present invention, in an injection molding die for obtaining an injection molded product having a large number of fine holes, the fine pin for hole forming can be moved up and down without being damaged by misalignment. The pin can be inserted into the mold, and the strength of the fine pin is ensured. Further, the mold releasability of the molded product is improved, and the molded product can be taken out without generating extra deformation.

[Brief description of the drawings]

FIG. 1 is an injection mold according to the present invention.

FIG. 2 is an injection mold according to the present invention.

FIG. 3 is an injection mold according to the present invention.

FIG. 4 is an injection mold according to a conventional method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ADP plate 2 CAV plate 3 COR plate 4 Guide bush 5 Guide pin 6 Taper guide 7 Fine pin for hole forming 8 Fine pin insertion hole 9 Spring 10 Insertion hole 11 CAV plate 12 COR plate 13 Guide bush 14 Guide pin 15 Guide hole 15 Fine Pin 16 Taper Guide 17 Fine Pin Insertion Hole

Claims (2)

[Claims] 1. A CAV plate, a COR plate,
A guide pin inserted into the insertion hole of the CAV plate and the COR plate, a taper guide for positioning the CAV plate and the COR plate, and a COR from the CAV plate side
In an injection mold having a fine pin inserted into an insertion hole of a plate, an ADP plate is provided on an upper part of the CAV plate so as to be vertically movable while being separated from the CAV plate,
Attach the ends of the fine pins to the ADP plate, hold them so that the tips of the fine pins do not protrude downward from the part surface of the CAV plate, and insert them into the insertion holes of the COR plate after closing the mold. An injection molding die characterized by the following. 2. The injection mold according to claim 1, wherein the ADP plate is supported above the CAV plate via a guide pin and a spring member.