JPS62261413A - Preventive device for tilting of core pin in mold for injection molding - Google Patents

Abstract

PURPOSE:To prevent surely the tilting of a core pin upon injection molding and contrive the improvement of the dimensional accuracy as well as the appearance of molded form by a method wherein both side surfaces of the core pin, inserted between both slide plates upon the closing of a mold, are supported by the tip ends of supporting pins planted in both slide plates. CONSTITUTION:A movable side temperature 4 is equipped with slide plates 4a, 4b slidably and slant holes 10a, 10b, bored on both slide plates 4a, 4b, are engaged with slant guide pins 11a, 11b, projected from a fixed side temperature 3 whereby the slide plates 4a, 4b are connected mutually when a mold is closed and both slide plates 4a, 4b are slid into left-and-right and opened when the mold is opened. At least one piece of supporting pin is planted on the contacting surfaces of slide cores 4a', 4b' and respective tip ends thereof are abutted against both sides of the core pin 9 inserted between the slide cores 4a', 4b' so as to be able to support the core pin 9 surely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a core pin fall prevention device in an injection mold.

[Conventional technology]

In conventional injection molds, in order to prevent the core pin from collapsing, a method is used in which the tip of the core pin is bitten into the stationary mold plate and interlocked, as shown in FIG.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional method, the part into which the core pin is bitten wears out in a short period of time, causing notches to occur on the outer periphery of the molded product at the tip. Particularly in molding materials with good fluidity, the
The amount of IJ is also large (there is a head during the protrusion, etc., which is very difficult to prevent!), and it is not easy to process the mold.Also, if there is no biting in the tip of the core pin, the metal When the resin material is filled into the mold, the core pins may fall down, causing problems such as uneven wall thickness of the molded product.

The object of the present invention is to solve the above-mentioned problems with conventional products and to improve the appearance and dimensional accuracy of molded products.

[Means for solving problems]

In order to achieve the above object, the present invention is configured as follows.

That is, the present invention provides an injection mold in which at least one support pin is implanted on each contact surface side of slide plates that open and close with each other, and the tip of each support pin is inserted between the control slide plates. There is a type in which the core pin is brought into contact with both sides of the core pin.

[For production]

As shown in Fig. 1, when the mold is closed, the slide plates (4a) and (4b) of the movable mold body also close, and the tips of the support pins (8) implanted on each contact surface side are Core pin (9) inserted between slide plates (4a) (4b)
) to securely support the core pin (9). Then, as shown in FIG. 2, when the mold is opened, the support pin (8) moves together with the slide boot plates (4a) and (4b), and the tip separates from the core pin (9).

[Example] In the figure, symbol (a) indicates the fixed side mold body of the mold, and Φ) indicates the movable side mold body. The fixed mold body (a) consists of a fixed mounting plate (1) fixed to the fixed die plate of the molding machine, a runner protruding plate (2), and a fixed mold plate (3), and the movable mold body Q: 1) refers to a movable mold plate (4) that approaches and separates from the fixed mold plate (3), a receiving plate (5), a spacer block (6), and a movable mounting plate that is fixed to the movable goo plate of the molding machine. (7). The movable side template (4) is slidably equipped with slide plates (4a) (4b), and oblique holes (LOA) (10b) are formed in both slide plates (4a) (4b), respectively. , the oblique guide pin (lla) protruding from the fixed side template (3)
(llb), and when the mold is closed as shown in Figure 1, both slide plays) (4a) and (4b) are joined to each other, and when the mold is opened, both slide play The slide plates (4a') (4b') are configured to open by sliding left and right. In addition, the above-mentioned slide play) (4a
) (4b) are fixed with slide cores (4a') (4b') whose tips move toward and away from each other.

In the present invention C2, the slide core (4a) (l
At least one fork pin (8) is implanted on the contact surface side of the slide core (b'), and the tip of each pin is attached to the slide core (
4a') (4b') There is a piece t which is made to come into contact with both sides of the core pin (9) inserted between them to ensure that the core pin (9) is supported. α2 is the guide pin of the stationary mold body (a), 0 is the runner tension pin, (14aX 14
b) is the ejector plate, a is the return pin, αe
1 is a fitting protrusion with an inclined inner surface that protrudes from the center of both ends of the fixed side mold plate (3).When the mold is closed, the slide plate (
The inclined surfaces at the outer ends of 4a and 4b fit together.

〔Effect of the invention〕

According to the present invention, when the mold is closed, both sides of the core pin inserted between both slide plates are supported by the tips of the fork pins implanted in both slide plates, so that the core pin does not fall during injection molding. It is possible to reliably prevent this and produce molded products that are satisfactory in terms of dimensional accuracy, appearance, and functionality.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; Fig. 1 is a cross-sectional view of the mold in a closed state, Fig. 2 is a cross-sectional view of the mold in an open state, and Fig. 3 is an enlarged view of that part. 4 is a sectional view taken along the line A--A in FIG. 3, and FIG. 5 is a sectional view 1 showing a conventional example. fil ~ Fixed side mounting plate, f2) ~ Runner protruding plate, (3
) ~ Fixed side template, (a) ~ Identification side template, (4) ~ Movable side template, (4a) (4b) ~ Slide plate, (5) ~
Reception plate, (6) ~S4-+- block, f7) ~Movable side mounting plate, li) ~Movable side mold body, (8) ~Support bin, (9)
~ Core pin.

Claims (1)

[Claims] A fixed side mold body (a) consisting of a fixed side mounting plate (1), a runner protruding plate (2), and a fixed side mold plate (3), and a movable side equipped with slidably slide plates (4a) (4b). Template(
4), is composed of a movable side mold body (b) consisting of a receiving plate (5), a spacer block (6), and a movable side mounting plate (7), and is provided with a sliding mechanism for the slide plates (4a) (4b). In the mold, at least one support pin (8) is implanted on each contact surface side of the slide plate (4a) (4b), and the tip of each support pin (8) is connected to the slide plate. (4a) A device for preventing a core pin from falling in an injection mold, characterized in that the device is brought into contact with both sides of a core pin (9) inserted between the two.