KR200441433Y1 - Inner undercut treating device for injection molding - Google Patents

Abstract

The present invention relates to a device for processing an inner undercut of an injection mold, and in particular, a stationary plate into which an injection molded product having an inner undercut is molded, a movable plate approaching and spaced apart from the stationary plate, and supported by the movable plate, An inner mold undercut processing apparatus of an injection mold comprising a core unit deformed by an opening operation and released from the inner undercut of the injection molded product, wherein the movable mold plate includes a first movable mold plate and a rear side of the first movable mold plate. And a second movable plate configured to be slidable with respect to the first movable plate, wherein the core unit is supported by the first movable plate and a core support portion supported by the second movable plate, and is fixed to an outer circumferential surface of the fixed plate. Sliding core is provided with a slider inclined toward the, and coupled to the outside of the sliding core to form an appearance Includes a plurality of deformable cores rotatably supported on the core support and the other side slidably coupled to the slider, so that each deformable core is inclined when the sliding core is moved in a direction opposite to the fixed plate. The cross-sectional area of the injection-molded side core unit is pivotally deformed by rotating in a mutually approaching direction along the slider, thereby releasing from the inner undercut of the injection-molded product.

Thereby, while improving the reliability of the inner undercut treatment process it is possible to reduce the design / manufacturing cost according to the injection mold manufacturing, it is possible to improve the durability of the injection mold.

Description

INNER UNDERCUT TREATING DEVICE FOR INJECTION MOLDING}

1 is a cross-sectional view of a molded state of the inner undercut processing apparatus of the injection mold according to an embodiment of the present invention,

Figure 2 is a perspective view of the core unit in the mating state shown in Figure 1,

3 is a cross-sectional view showing a state in which the movable plate shown in FIG. 1 is separated from the stationary plate;

4 is a cross-sectional view showing the movement of the sliding core in the detached state shown in FIG.

Figure 5 is a perspective view of the core unit in the state shown in Figure 4,

6 is a cross-sectional view showing a state that the ejected plate is moved to eject the ejection plate shown in FIG.

7 is a cross-sectional view of a molded state of the inner undercut processing apparatus of the injection mold according to another embodiment of the present invention,

8 is an exploded perspective view of the core unit in the mating state shown in FIG. 7;

9 is a cross-sectional view showing a state in which the movable die illustrated in FIG. 7 is separated from the stationary die;

10 is a cross-sectional view showing the movement of the sliding core in the separated state shown in Figure 9,

FIG. 11 is a cross-sectional view illustrating a state in which an ejected product is taken out by moving the eject plate shown in FIG. 9.

* Description of the symbols for the main parts of the drawings *

10: fixed plate, 15: cavity,

20: movable plate, 21: eject plate,

25: the first movable plate, 27: the second movable plate,

50: core unit, 51: sliding core,

52: through part, 53: first modified core,

54: male portion, 55: second modified core,

56: slider, 57: core support,

60: rib forming portion, 61: rib mill plate,

62: rib groove, 63: connecting rod,

65: locking portion, 100: injection molding,

101: rib.

The present invention relates to an inner undercut treatment apparatus for an injection mold, and in particular, while improving the reliability of the inner undercut treatment process, it is possible to reduce the design / manufacturing cost according to the injection mold, and to improve the durability of the injection mold. An inner undercut processing apparatus of an injection mold.

In general, an injection mold is formed by injecting and cooling a high-temperature liquid resin into a cavity provided between a stationary plate and a movable plate to form a product, and then moving the movable plate to open the mold to open the mold. The molded product is taken out to the outside.

At this time, if there is no undercut such as a thread inside the injection molding, it is possible to take out the work while reciprocating the movable die in the longitudinal direction, but if there is an inner undercut, the movable die must be moved in the longitudinal direction and its orthogonal direction. There is a problem that ejection of the injection molding is possible.

As a constitution for processing an undercut formed inside the above-mentioned injection molding, a screw thread is formed at the tip of the core having a diameter corresponding to the inside diameter of the injection molding, and the inner undercut taking out of the rotation system is configured such that the core is rotated when the product is taken out. There was a way.

However, in the conventional ejection method, in order to rotate the core, a rotary driving device must be further provided in addition to the driving device in the longitudinal direction of the movable die, thereby increasing the cost required for manufacturing the mold and increasing the volume of the injection mold itself. There was a problem such as difficult to manufacture / transport / assemble the mold as well as restrictions on the installation place.

On the other hand, Korean Utility Application No. 1993-0007027 is composed of a slide core sliding in the lateral direction in the cavity by the angular cam, and a deformation mill sliding in the front and rear direction in the cavity along the eject plate which is raised and lowered toward the stationary plate A technology relating to an undercut treatment apparatus has been disclosed.

However, in the case of the above-described undercut processing apparatus, the slide core and the angular cam are distributed in the stationary plate and the movable plate, respectively, so that the design / change of the mold is not easy, and thus the mold manufacturing cost increases.

In addition, since the movement directions of the slide core and the deformation mill are different from each other, at least two steps of operations must be performed for each movement direction, and thus the number of processes increases so that the total cycle time for the production of the injection molding is increased. .

In addition, since each core piece is moved and contracted only in two directions perpendicular to each other, the core end is not uniformly shrunk in each radial direction, thereby reducing the reliability of the inner undercut treatment process and the flexibility of the injection molding design.

In addition, the undercut treatment device having the above-described configuration may not only form ribs on the inner bottom of the injection molding, but also may cause the movement marks of the deformation core to remain on the inner bottom of the injection molding, resulting in unclean products. there was.

Accordingly, an object of the present invention, while improving the reliability of the inner undercut treatment process can reduce the design / manufacturing cost according to the injection mold manufacturing, to provide an inner undercut processing apparatus of the injection mold that can improve the durability of the injection mold. There is.

Another object of the present invention is to provide an injection mold inner undercut processing apparatus that can easily take out an injection molded rib formed on the inner bottom, and can prevent deformation core movement marks on the inner bottom of the injection molded product. have.

The object is, according to the present invention, the stationary plate to which the injection molding having the inner undercut is molded, the movable plate which is approached and spaced apart from the stationary plate, and supported by the movable plate and deformed by the opening operation of the movable plate In the injection mold inner undercut processing apparatus comprising a core unit released from the inner undercut of the injection molding, the movable die plate, the first movable die plate and the first movable die plate from the rear of the first movable die plate. And a second movable plate configured to be slidable with respect to the core unit, wherein the core unit includes a core support part supported by the first movable plate, and a slider supported on the second movable plate and inclined toward the fixed plate on an outer circumferential surface thereof. Sliding core is provided, coupled to the outside of the sliding core to form an appearance and one side is rotatable to the core support portion A plurality of deformation cores supported and slidably coupled to the slider, the directions in which the respective deformation cores approach each other along the inclined slider when the sliding core is moved in a direction opposite to the fixed plate; It is achieved by the inner undercut treatment apparatus of the injection mold is rotated to the cross-sectional area of the injection-molding side core unit by the shrinkage deformation, which is released from the inner undercut of the injection molding.

Here, the deformation core is provided with a first deformation core and a second deformation core, which are provided in three each and are arranged to cross each other along the outer periphery of the sliding core, it is preferable that the cross-sectional area of the injection-side core unit is uniformly contracted. Do.

Here, provided between the first movable plate and the fixed plate, the core unit may further include an eject plate to move toward the fixed plate in a state released from the inner undercut of the injection molding to separate the injection molding have.

Here, a rib mill plate formed with rib grooves for forming the rib inside the injection molding on one side, one end is connected to the rib mill plate, the other end extending through the through portion provided in the sliding core, and the other end of the connecting rod It may further include a rib forming portion having a locking portion provided in the end of the sliding core to be held.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view of a molded state of the inner undercut treatment apparatus of the injection mold according to the present invention, Figure 2 is a perspective view of the core unit in the bonded state shown in FIG.

Referring to the drawings, the inner undercut treatment apparatus of the injection mold according to the present invention, a fixed mold plate 10 is molded, the injection molding 100 having an inner undercut, and a movable mold plate that is approached and spaced apart from the fixed mold plate 10 ( 20 and a core unit 50 supported by the movable die 20 and deformed by the opening operation of the movable die 20 to be released from the inner undercut of the injection molded product 100 and drawn out.

Here, the movable die 20 is the opposite side of the stationary plate 10 with the first movable die 25 and the first movable die 25 between which the reciprocating movement is performed and spaced apart from the stationary die 10. It includes a second movable plate 27 is provided to be movable with respect to the first movable die plate 25.

An ejection plate 21 may be provided between the stationary plate 10 and the first movable plate 25 to eject the injection molded product 100 from the first movable plate 25.

The core unit 50 includes a core support part 57, a sliding core 51, and a plurality of deformation cores 53 and 55.

The core support part 57 is supported by the first movable plate 25 and reciprocates with respect to the stationary plate 10 integrally with the first movable plate 25.

A sliding core 51 penetrates and moves through the center of the core support part 57, and a plurality of deformation cores 53 and 55 are hinged to the edge of the core support part 57 to be rotatable.

One end of the sliding core 51 is fixed to the second movable plate 27, and the other end of the sliding core 51 extends toward the injection molding through the core support 57.

The sliding core 51 is provided in a rod-shaped shape in which the cross-sectional area is reduced toward the stationary plate 10 as a whole, and a slider 56 coupled to each of the deformation cores 53 and 55 is formed on the outer circumferential surface of the sliding core 51. have.

The slider 56 is formed along the longitudinal direction of the sliding core 51 and has a shape corresponding to the inner side of each of the deformation cores 53 and 55, so that the deformation cores 53 and 55 coupled to the sliding core 51. ) Is possible to flow in the longitudinal direction of the slider 56, but is not possible to flow in the horizontal direction in the longitudinal direction.

Here, the slider 56 may be provided in a number corresponding to each of the deformation cores 53 and 55, and may be provided in various shapes.

2, the deformable cores 53 and 55 are coupled to the outside of the sliding core 51 to form an appearance of the core unit 50.

Deformation cores 53 and 55 may be provided in various ways. For example, as shown in FIG. It may be provided as a second deformation core 55.

The first deformable core 53 and the second deformable core 55 may be provided in various numbers, respectively, may be provided in three or more, or may be provided in two.

Here, in the case where three or more first deformation cores 53 and second deformation cores 55 are provided, each of the deformation cores 53 and 55 may contract uniformly in each radial direction. There is this.

On the other hand, the shape of the first deformed core 53 and the second deformed core 55 may be modified in various ways as necessary.

Hereinafter, an operation process of the inner undercut treatment apparatus of the injection mold having the above-described structure will be described in detail with reference to FIGS. 1 to 6.

First, FIG. 1 illustrates a state in which the stationary plate 10 and the movable plate 20 are combined.

The stationary plate 10 is provided with a cavity 15 in which the outer side of the injection molding 100 is molded, and the movable plate 20 is moved toward the stationary plate 10.

In this case, as shown in FIG. 2, the core unit 50 has a sliding core 51 located therein, and includes a first deformed core 53 and a second deformed core along the outside of the sliding core 51. 55 is in the engaged state with the slider 56.

Liquid resin is injected into the cavity 15 through a resin injection hole (not shown) provided in the stationary plate 10, and the injection molding 100 is molded. An undercut is formed inside the injection molding 100 by a male screw portion 54 formed on the outer circumferential surfaces of the respective deformation cores 53 and 55.

Next, when the molding of the injection molding 100 is completed, as shown in FIG. 3, the first movable plate 25, the second movable plate 27, and the eject plate 21 are integrally formed as the stationary plate 10. Spaced apart.

At this time, the outside of the injection molding 100 is in a state of being separated from the cavity 15 and exposed to the outside.

And, as shown in Figure 4, the eject plate 21 and the first movable plate 25 is in the stopped state, the second movable plate 27 performs a further movement in the a direction, in this case, the second The sliding core 51 coupled to the movable die 27 is moved along the second movable die 27 in the a direction (see the cross-sectional line `` X-X '' in FIGS. 2 and 4).

The sliding core 51 is coupled to each of the deformation cores 53 and 55 through the slider 56, and the slider 56 is inclined toward the stationary plate 10, so that the sliding core 51 Accordingly, each of the deforming cores 53 and 55 moves together along the slider 56 and is brought together toward the center of the sliding axis (see b direction in FIG. 4).

That is, referring to FIG. 5, the sliding cores 51 are moved backward along the second movable plate 27, and each of the deformation cores 53 and 55 is gathered to the center along the slider 56. The cross-sectional area of the core unit 50 of the injection-molded product 100 is reduced.

Finally, the eject plate 21 located in front of the first movable plate 25 moves toward the stationary plate 10 while pushing the ejected material 100 over the end of the core unit 50 to take it out (Fig. C direction of 6).

Therefore, according to the inner undercut treatment apparatus of the injection mold according to the present invention, when taking out the injection molded product formed with the inner undercut, such as a container lid, the inner undercut is processed simply by moving the first movable plate and the second movable plate in sequence. Since it is possible to eliminate the need for a separate driving device for the rotation of the core unit, it is easy to manufacture the mold, and the manufacturing cost is reduced.

In addition, since the movable die does not need to perform an additional complicated driving step for the inner undercut treatment, the injection molding process is simplified to improve productivity, and the durability of the injection mold is also increased.

In addition, the deformation core is composed of three or more first deformation cores and second deformation cores, respectively, so that the core unit is contracted uniformly in each radial direction, thereby improving reliability of the inner undercut treatment process, and proportionally to the inner undercut. Less constraints on the design increase the design flexibility of the injection molding.

7 is a cross-sectional view of a molded state of the inner undercut treatment apparatus of the injection mold according to another embodiment of the present invention, Figure 8 is a perspective view of the core unit in the molded state shown in FIG.

Referring to FIGS. 7 and 8, the rib forming part 60 includes rib grooves 62 for forming ribs 101 (eg, rings or packings) inside the injection molding 100 on one side thereof. The formed rib mill plate 61, one end is connected to the rib mill plate 61, the other end of the connecting rod 63 extending through the through portion 52 provided in the sliding core 51, and the connecting rod 63 It is provided on the other end is provided including a catching portion 65 to block the movement of the end of the sliding core (51).

A rib for sealing the container (not shown) containing the contents (for example, cosmetics, etc.) by the pressing action on the inner bottom of the injection molding 100 to prevent the contents from leaking out or foreign substances from flowing in from the outside ( 101 may be formed.

Rib 101 may be provided in various ways corresponding to the shape of a circular ring or a container.

The container has a male thread formed at the outer periphery of the inlet, and the male screw is rotated and screwed with the female thread formed inside the injection molding. The container is moved up and down by a pitch corresponding to the thread pitch, so that the coupling between the container and the injection molding 100 is achieved. Is done.

When the coupling of the container and the injection molding 100 is completed, the inlet end of the container and the rib 101 are tightly sealed to prevent leakage of the contents.

Rib 101 is a male threaded portion of the container and the female threaded portion of the injection molding 100 when the period of use has elapsed or is formed with a gap between each other depending on the use environment, foreign matter caught between the gaps or the flow into the interior of the container You can prevent it.

The rib mill plate 61 is provided with a rib groove 62 recessed in a predetermined width in the direction of the sliding core 51 for forming the rib 101 formed on the inner bottom of the injection molded product 100 at a predetermined position.

The outer diameter of the rib mill plate 61 is preferably formed smaller than the inner diameter of the injection molding 100 so as not to be caught by the undercut (male thread portion) inside the injection molding when the rib mill plate 61 is released (or separated) from the injection molding.

One end of the connecting rod 63 is connected to the rib mill plate 61, and the other end thereof extends through the through part 52 provided in the sliding core 51 to protrude up to the second movable plate 27.

The through part 52 of the sliding core 51 is coupled to the connecting rod 63 so as to be movable at a predetermined interval. Therefore, the sliding core 51 and the connecting rod 63 can be moved relative.

The connecting rod 63 may be provided in various ways, such as a bar shape, in a satisfying condition in which the penetrating portion 52 of the sliding core 51 is movable.

The other end of the connecting rod 63 is provided with a catching portion 65 formed to protrude to the outer radius of the connecting rod 63, when the sliding core 51 is moved, the end of the sliding core 51 is caught, the predetermined distance or more Block the move.

 Hereinafter, an operation process of the inner undercut treatment apparatus of the injection mold according to another embodiment of the present invention will be described in detail with reference to FIGS. 7 to 11.

7 to 11, in the process of forming the injection molding 100 by injecting the liquid resin into the cavity 15 through the resin injection hole, the deformation cores 53 and 55 are disposed at predetermined positions of the inner periphery of the injection molding 100. The undercut is formed by the rib, and the rib 101 is formed on the inner bottom of the injection molded product 100 by the rib groove 62 of the rib mill plate 61 provided on one side of the rib molding part 60.

When the molding of the injection molded product 100 is completed, as shown in FIG. 9, the first movable plate 25, the second movable plate 27, and the eject plate 21 are integrally spaced from the fixed plate 10. .

As shown in FIG. 10, the second movable plate 27 performs further movement in the a direction while the eject plate 21 and the first movable plate 25 are stopped.

At this time, the sliding core 51 coupled to the second movable plate 27 is moved in the a direction along the second movable plate 27 and each of the deformation cores 53 and 55 according to the movement of the sliding core 51. ) Move along the slider 56 toward each other toward the center of the sliding axis so that the cross-sectional area of the core unit 50 of the injection-molded product 100 is reduced (see b direction in FIG. 10).

In this way, while the cross-sectional area of the core unit 50 is reduced, the undercut is released (or separated) and the injection molded product 100 is taken out.

At this time, since the rib mill plate 61 is provided between each of the deformation cores 53 and 55 and the injection molding 100, scratches due to movement of each deformation core 53 and 55 on the bottom of the injection molding 100 may be prevented. In addition, movement marks of the deformation cores 53 and 55 are not generated.

In this process, the sliding core 51 and the rib molding portion 60 is moved to the rear side.

In addition, when the sliding core 51 moves, one end of the sliding core 51 is caught by the engaging portion 65 of the connecting rod 63 coupled to the through portion 52 of the sliding core 51, so that further movement is prevented. Is blocked.

Here, the moving distance of the sliding core 51 or the extension length T1 (see FIG. 9) of the connecting rod 63 is spaced apart from the second movable plate 27 spaced apart by moving in the a direction from the first movable plate 25. It is preferable that the distance T2 is provided corresponding to the distance T2 (see FIG. 10).

Referring to FIG. 11, the eject plate 21 located in front of the first movable plate 25 moves toward the stationary plate 10, and pushes the injection product 100 over the end of the core unit 50. It is easily taken out (see c direction in Fig. 11).

In this process, since the outer diameter of the rib mill plate 61 is formed smaller than the inner diameter of the injection molding 100, the rib mill plate 61 can be easily released (or separated) from the injection molding because it is not caught by the undercut inside the injection molding. .

Therefore, according to the inner undercut treatment apparatus of the injection mold according to the present invention, when taking out the injection molded product formed with the inner undercut, such as a container lid, the inner undercut is processed simply by moving the first movable plate and the second movable plate in sequence. Since it is possible to eliminate the need for a separate driving device for the rotation of the core unit, it is easy to manufacture the mold and the manufacturing cost is reduced.

In addition, since the movable die does not need to perform an additional complicated driving step for the inner undercut treatment, the injection molding manufacturing process is simplified to improve productivity, and the durability of the injection mold is also increased.

In addition, the deformation core is composed of three or more first deformation cores and second deformation cores, respectively, so that the core unit is contracted uniformly in each radial direction, thereby improving reliability of the inner undercut treatment process, and proportionally to the inner undercut. Less constraints on the design increase the design flexibility of the injection molding.

In addition, the ribs of various shapes formed on the inner bottom of the injection molding can be easily taken out by the rib molding unit provided in the rib groove to be applied to various products such as cosmetic caps, and the shape of the deformation core on the inner bottom of the injection molding. The aesthetics can be improved by preventing the formation of marks.

Claims (4)

A stationary plate into which an injection molded product having an inner undercut is molded, a movable plate approaching and spaced apart from the stationary plate, and supported by the movable plate and deformed by an opening operation of the movable plate to be released from the inner undercut of the injection molded product In the inner undercut processing apparatus of the injection mold comprising a core unit, The movable die plate has a first movable die plate and a second movable die plate which is slidably provided with respect to the first movable die plate at the rear of the first movable die plate, The core unit includes a core support part supported by the first movable plate, a sliding core supported by the second movable plate, and having a slider inclined toward the fixed plate on an outer circumferential surface thereof, the outer core being coupled to the outside of the sliding core And a plurality of deformation cores, one side of which is rotatably supported by the core support and the other side of which is slidably coupled to the slider. When the sliding core is moved in the opposite direction of the stationary plate, the respective deformation cores are rotated in a direction of mutual access along the inclined slider so that the cross-sectional area of the core unit on the injection-side side shrinks and deforms, whereby the inner undercut of the injection-molded body Released from Between the deformation core and the injection molding, a rib mill plate having a rib groove for forming the rib inside the injection molding on one side, and one end is connected to the rib mill plate and the other end extending through the through portion provided in the sliding core and And a rib molding part provided at the other end of the connecting rod and having a locking part held at an end of the sliding core. The method of claim 1, Each of the deformation cores is provided as a first deformation core and a second deformation core, which are provided in three and intersect with each other along the outer periphery of the sliding core, so that the cross-sectional area of the injection-side core unit is uniformly shrunk. Inner undercut treatment device of injection mold. The method according to claim 1 or 2, It is provided between the first movable plate and the fixed plate, characterized in that it further comprises an eject plate for separating the injection molding by moving toward the fixed plate in the state that the core unit is released from the inner undercut of the injection molding Inner undercut treatment device of injection mold. delete

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