JPH081727A - Injection mold - Google Patents

Abstract

PURPOSE:To provide an infection mold wherein a mold break stroke is not limited, a stroke of a knockout plate can be shortened and a molded product can be released by opening the knockout plate reliably and stably. CONSTITUTION:This injection mold is provided with a knockout plate 3 or the knockout plate 3 and ejector pin 7, two links 11, 11 sitting astride of both of a movable retainer plate 4 and the knockout plate 3 are provided on both side faces of them confronted with each other symmetrically to the right and left and flatplate cams 16 which advance in a beeline and are positioned between both the links 11, 11 at the time of mold clamping are provided in both side faces of retainer plate 2 facing on each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding die having a knockout plate or a knockout plate and an ejector pin, which is capable of reliably and stably opening the knockout plate to release a molded product. It is about the type.

[0002]

2. Description of the Related Art In an injection molding die, a method of taking out a molded product which is cooled and solidified in the die is mainly a method of using an ejector pin (including an inclined pin),
It is classified into a method using a knockout plate and a method using in combination with. Among these, the method generally used is applied to a molded product having a relatively small release resistance. Has a large mold release resistance, and the ejector pin method is applicable to those in which the molded product may be deformed or the ejector pin may be depressed, and the molded product may not leave a trace of the ejector pin. Normally, it is operated by the eject mechanism of the molding machine, but when the molded product is taken out by automatic drop, the fixed side mold plate and the knockout plate are connected with a slider or a chain, and the mold opening operation is used to end the mold opening. There are also those that activate the knockout plate immediately before. The method of is applied when the trace of the ejector pin is allowed. For this, the ejector pin and the knockout plate are connected to the ejector plate, and the ejector rod of the molding machine is pushed out to operate simultaneously and with the same stroke.The fixed side mold plate and the knockout plate are connected via a slider. , There is a method in which the knockout plate is operated first immediately before the end of the mold opening by using the opening operation of the mold, and then the ejector pin is pushed out at an arbitrary stroke.

FIGS. 5 and 6 illustrate different aspects of the above-described system. In the example illustrated in FIG. 5, the fixed-side mold plate b is fixed to the fixed-side mounting plate a, and the knock-out plate c is set to the movable side. A template plate d, a spacer block e, and a movable side mounting plate f are sequentially fixed, and an ejector plate h incorporating an ejector pin g is provided in the spacer block e, which is connected to a knockout plate c by a connecting member i [Figure (A)], when the ejector plate h is pushed out by the ejector rod j of the molding machine, the knockout plate c and the ejector pin g are simultaneously actuated so that the molded product k can be taken out [see FIG. (B)]. .
On the other hand, in the example illustrated in FIGS. 6A to 6C, sliders m are provided on the opposite side surfaces of the knockout plate c and the fixed-side mold plate b to face each other, and the sliders m are connected to each other. The knockout plate c is pulled by the slider m so as to move a little from the movable side mold plate d, whereby the molded product k is dissociated from the mold to reduce the mold release resistance, and the ejector pin g is lightly acted. It is operated by force so that the molded product k can be taken out. As described above, in the method in which the knockout plate and the ejector pin are used together, the load on the ejector pin is less than that in the case where the ejector pin is used alone, and it is possible to effectively prevent the pin from sinking or piercing the molded product. The knockout plate acts on the peripheral portion of the molded product and the portion embedded in the movable side mold plate, and has a larger active area than the ejector pin, and since the pushing force is not biased, deformation of the molded product is small. Even if the mold release resistance is large such as in a deep molded product, the knockout plate can be forcibly disengaged from the mold by just moving a little, and the mold release resistance can be greatly reduced to eject the ejector pin with a light force. You can

[0004]

However, in this method, the stroke may be considerably long depending on the depth of the product. From the original function of the knockout plate, the stroke is too long and wasteful, and the ejector pin is burdened. Is not significantly reduced. The method using the slider can shorten the stroke of the knockout plate and reduce the load on the ejector pin, but the mold opening stroke is limited by the length of the slider. To solve the waste of stroke, the knockout plate and the ejector pin must operate independently. Therefore, in order to operate the knockout plate, it is necessary to use a mold opening operation or a hydraulic mechanism, and in order to avoid a method such as a slider in which the mold opening stroke is limited, for example, it is attached to the fixed side and the movable side. The mechanical parts must be separated by mold opening. The present invention solves these problems by developing this slider system and combining a link or "lever" with a rectilinear flat plate cam. Therefore, an object of the present invention is to perform injection molding capable of shortening the stroke of the knockout plate without limiting the mold opening stroke, and reliably and stably opening the knockout plate to release the molded product. To provide the mold.

[0005]

An injection molding die according to the present invention is an injection molding die having a knockout plate or a knockout plate and an ejector pin,
Two links that straddle the movable side template and the knockout plate are provided symmetrically on both sides, and a straight type that is located between both links when closed on both sides of the fixed side template that face each other. Should be provided with a flat cam,
Two levers, one end of which is in contact with the mold surface of the movable side mold plate, are provided symmetrically on both side surfaces of the knockout plate facing each other, and on both side surfaces of the fixed side mold plate facing each other are positioned between the levers when closed. It is characterized in that a straight-moving flat plate cam is provided.

[0006]

In the injection-molding die having the above-mentioned structure, when the mold is opened,
Between the two symmetrical sides of the movable side template and the knockout plate, which are provided on both sides of the knockout plate, or between the two opposite sides of the knockout plate, one end of the movable side template is a mold of the movable side template. Bilateral symmetry that touches the surface
By passing between the levers, the cam portion at the tip of the rectilinear flat plate cam provided on the opposite side surfaces of the fixed-side template passes,
The movable link and the knockout plate can be opened by pushing the two links outward or rotating the two levers outward.

[0007]

EXAMPLES The details of the injection mold according to the present invention will be described below.
Description will be made based on the embodiment shown in FIGS. FIG.
Shows a first embodiment of the injection mold of the present invention, in which (a) is a longitudinal sectional view and (b) is a side view of FIG. (A). 2 (a) to 2 (d) show the movement of the injection molding die at the time of opening the mold in the order of operation by the partial side view of FIG. 1 (a). 1 and 2, 1 is a fixed side mounting plate, 2 is a fixed side template, 3 is a knockout plate, 4 is a movable side template, 5 is a spacer block, 6 is a movable side mounting plate, 7 is an ejector pin, 8 is an ejector plate, 9
Is a cavity, and 10 is a molding machine ejector rod. 1
Numerals 1 and 11 are two V-shaped links provided on both opposite sides of the knockout plate 3 and the movable side mold plate 4 facing each other with a gap, and both ends are movable with the knockout plate 3 respectively. It is rotatably attached to each of the side mold plates 4 and has an X shape as a whole. Reference numeral 16 denotes a straight-moving flat plate cam in which a base portion 17 is fixedly mounted on opposite side surfaces of the fixed-side mold plate 2 and a cam portion 18 at the tip extends to the movable side. When closed, a cam between the base portion 17 and the cam portion 18 A portion 19 narrower than the portion 18 is mounted so as to be located between the links 11, 11.

In this injection molding die, the cavity 9
When the molten resin is injected and solidified inside, the movable side mounting plate 6, the mold plate 4, the knockout plate 3 and the like are retracted to open the mold. Then, as the knockout plate 3 and the movable side mold plate 4 move, the knockout plate 3
The two links 11 and 11 which are attached to the movable side mold plate 4 and the movable side mold plate 4 are straight-moving flat plate cams 16 located between them.
It will move along the left and right side surfaces of the cam part 18, especially the shape of both side surfaces of the cam portion 18, and when moving around it, the space between both links 11, 11 will be expanded, and with it, both links 11, 11
By pushing the knockout plate 3 to which one end of is attached to the fixed side opposite to the mold opening direction, the knockout plate 3 and the movable side mold plate 4 are opened at a fixed distance, and the molded product 20 in the cavity 9 is opened. The movable side mold plate 4 is dissociated.
After the mold opening is completed, in this apparatus, the molded product 20 is taken out by the action of the molding machine ejector rod 10 regardless of the knockout plate 3. When closing the mold, when the knockout plate 3 and the movable-side mold plate 4 are left open for a certain distance, the movable-side mold plate 4 contacts the fixed-side mold plate 2 by advancing with the movable-side mounting plate 6 or the like. Both links 11 and 11 opened symmetrically
Passes through the left and right sides of the cam portion 18 of the straight-moving flat plate cam 16 and reaches the left and right sides of the portion 19 between the base portion 17 and the cam portion 18 which is narrower than the cam portion 18, and the next knockout plate 3 And the movable side template 4 are in close contact with each other
11 and 11 are bent to sandwich the straight-moving flat plate cam 16 in the narrowed portion 19, and restore the old state.

FIG. 3 relates to a second embodiment of the injection molding die of the present invention, in which (a) is a longitudinal sectional view and (b) is FIG. (A).
FIG. FIGS. 4 (a) to 4 (c) show the movement of the injection-molding die at the time of opening the mold in the order of operation by the partial side view of FIG. 3 (a). In FIGS. 3 and 4, 21 is a fixed side mounting plate, 22 is a fixed side template, 23 is a knockout plate, 24 is a movable side template, 25 is a spacer block, 26 is a movable side mounting plate, 27 is an ejector pin, 28 is an ejector plate, 29 is a cavity, and 30 is a molding machine ejector rod. Reference numerals 31 and 31 denote two L-shaped "leveres" which are provided on opposite side surfaces of the knockout plate 23 so as to be rotatable symmetrically at fulcrums 32 and 32 at intervals with respect to each other. One side 33, 33 is in contact with the mold surface of the movable side mold plate 24 (or the side surface of the support plate 34 attached along the mold surface as shown in the figure, hereinafter referred to as both mold surfaces in the present invention), and at the other end. The cars 35, 35 are rotatably provided. 36
Is a rectilinear type flat plate cam in which base portions 37 are fixedly provided on opposite side surfaces of the fixed-side mold plate 22 and a cam portion 38 at the tip extends to the movable side.
When closed, a portion 39 between the base portion 37 and the cam portion 38, which is narrower than the cam portion 38, is mounted so as to be located between the wheels 35, 35 of the levers 31, 31.

In this injection mold, the cavity 29
When the molten resin is injected and solidified therein, the movable side mounting plate 26, the mold plate 24, the knockout plate 23, and the like are retracted to open the mold. Then, as the knockout plate 23 moves, the pair of levers 31, 31 provided on the knockout plate 23 move along the shapes of the left and right side surfaces of the straight-moving flat plate cam 36 located between them, particularly the side surfaces of the cam portion 38. When moving around it, both levers 31 and 31 cars 35 and 35
Widen the space between the levers 31, 31
By rotating the mold surface of the movable side mold plate 24 at the other end by pressing the mold surface of the movable side mold plate 24 at the other end, a predetermined distance is opened between the knockout plate 23 and the movable side mold plate 24, and a molded product in the cavity 29 (not shown). No)
Is dissociated from the movable side mold plate 24. After the mold opening is completed, in this apparatus, the molded product is taken out by the action of the ejector rod 30 of the molding machine regardless of the knockout plate 23. At the time of mold closing, when the knockout plate 23 and the movable side mold plate 24 are moved forward with the movable side mounting plate 26 or the like while keeping a certain distance between them, similar to the above-described embodiment, the vehicle 35 rotates symmetrically. The levers 31 and 31 with the gaps between the levers 35 and 35 pass through the left and right sides of the cam portion 38 of the straight-moving flat plate cam 36, and when the knockout plate 23 contacts the fixed-side template 22, both levers 31, 31
Cars 35, 35 are narrow portions of straight type flat cam 36 19
To the left and right sides of both, and by the close contact between the next knockout plate 23 and the movable side mold plate 24, both levers 31, 31 are fulcrum 32,
When the levers 31 and 31 are rotated about 32, the wheels 35 and 35 of the levers 31 and 31 clamp the straight-moving flat plate cam 16 at the narrowed portion 19 to restore the old state.

The present invention is not limited to the link and the structure of the "lever" shown in the above embodiment, and can be appropriately modified without departing from the gist of the invention.

[0012]

According to the injection molding die of the present invention, it is possible to reliably and stably open the required amount of the knockout plate by the force increasing action of the link or the lever. The maximum amount of mold opening stroke is not limited. Attaching a link or "lever" to the side of the mold makes it easy to modify the existing mold, and it is easy to check and adjust during use.

[Brief description of drawings]

FIG. 1 relates to a first embodiment of an injection-molding die according to the present invention, (a) of which is a vertical sectional view, and (b) is a side view of (a).

2 (a) to 2 (d) are views showing the operation of the injection molding die shown in FIG. 1 at the time of opening the mold in the order of operation by the partial side view of FIG. 1 (a).

FIG. 3 relates to a second embodiment of an injection molding die according to the present invention, (a) of which is a vertical sectional view, and (b) is a side view of (a).

4 (a) to (c) show, in the order of operation, the movement of the injection molding die shown in FIG. 3 at the time of opening the mold, with reference to a partial side view of FIG. 3 (a).

5A and 5B are vertical cross-sectional views showing an example of a conventional injection molding die in the order of operation.

6A and 6B relate to another example of a conventional injection molding die, in which FIG. 6A is a longitudinal sectional view, and FIGS. 6B and 6C show the movement of the die when the mold is opened. It is shown in order of operation by a side view.

[Explanation of symbols]

1, 21 ... Fixed side mounting plate, 2, 22 ... Fixed side template, 3, 23 ... Knockout plate, 4, 24 ...
Movable mold plate, 5, 25 ... Spacer block,
6, 26 ... Movable side mounting plate, 7, 27 ... Ejector pin,
8, 27 Ejector plate, 9, 29 Cavity, 10, 30 Molding machine Ejector rod, 11 Link, 31 Lever,
32 …… fulcrum, 33 ‥ one side, 34 ‥
Support plate, 35 ・ ・ ・ Car, 16, 36 ・ ・ ・ Straight type flat cam, 17, 37 ・ ・ ・ Base part, 18, 38 ・ ・ ・ Cam part, 19, 39 ・ ・ ・ Narrow part 20 ・ ・ ・ Molded product. a: Fixed side mounting plate, b
... fixed side template, c ... knockout plate,
d: movable side template, e: spacer block,
f: Movable side mounting plate, g: Ejector pin,
h ... ejector plate, i ... coupling member,
j: Molding machine ejector rod, k: Molded product, m: Slider.

Claims (2)

[Claims] 1. A knockout plate or an injection molding die including a knockout plate and an ejector pin, wherein two links extending across the movable side mold plate and the knockout plate are provided symmetrically on opposite side surfaces of the mold plate and the knockout plate. At the same time, an injection molding die characterized in that a straight-moving flat plate cam positioned between both links when the mold is closed is provided on both opposite sides of the fixed-side mold plate. 2. An injection molding die comprising a knockout plate or a knockout plate and an ejector pin, wherein two levers, one end of which is in contact with the die surface of the movable side die plate, are provided on opposite side surfaces of the knockout plate. An injection molding die characterized in that it is provided symmetrically and a straight-moving flat plate cam positioned between the levers when the mold is closed is provided on both opposite sides of the fixed-side mold plate.