KR101955310B1 - Injection mold having under-cut avoiding function - Google Patents

Abstract

The present invention relates to an injection mold having an undercut avoidance function. The injection mold comprises: a fixed mold part including a fixed mold frame which provides support force, and an upper core which is mounted on the fixed mold frame; and a movable mold part including a movable mold frame which moves forward and backward with respect to the fixed mold part, a core assembly which is mounted on the movable mold frame, is arranged to correspond to the upper core while the movable mold frame is in close contact with the fixed mold frame, and provides an injection space for molding an injection-molded product having an undercut between the upper core and the core assembly, and a core assembly driving part which operates the core assembly in a state in which the upper core is widened after injection, pushes the undercut of the injection-molded product to the outside of the core assembly by a part of the core assembly, and allows the injection-molded product to be taken out without being interfered with the core assembly. The injection mold having an undercut avoidance function of the present invention secures a separation path of the mold trapped in a product by physically elastically deforming an undercut of a molded product, and thus it is possible to easily take out the product with respect to the mold and simply configure a taking-out structure.

Description

[0001] The present invention relates to an injection mold having an undercut avoiding function,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for injection molding, and more particularly, to an injection mold having an undercut avoiding function capable of easily taking out a molded article having an undercut portion from a mold.

Injection molding for producing various kinds of plastic products includes a series of processes in which a thermoplastic or thermosetting molding material is heated and melted inside a molding machine, then press-fitted and filled into a cavity inside the injection mold using a screw feeder, and cooled and taken out .

That is, the synthetic resin used for injection molding, that is, the molding material passes through the injection space such as the runner and gate, is injected into the cavity of the mold as the molding space, is molded under the high pressure, , And the mold is opened and separated from the mold by a plate and a pin. Injection molding is a way to precisely and quickly produce various shapes of products.

On the other hand, in the case where the product to be produced through injection molding has an undercut portion, it is difficult to take out the product from the mold, so that the structure of the mold is complicated for taking out the product.

The undercut is a part of the product, which is caught by the metal mold at the time of taking out and interferes with the extraction. Conventionally, in order to take out a molded article having an undercut, an undercut of a molded article is formed in the mold, and a slide core which can be slidably moved is used to peel off the molded article. An undercut is formed in the product by the slide core, and when the slide core is slid and separated from the product, the product can be taken out.

However, the injection mold having such a conventional undercut extraction device has a disadvantage in that the structure becomes very complicated when a large number of slide cores are used. For example, a case drum used in a vacuum cleaner is required to be inserted into a mold when a circular slide core is inserted into a mold for molding a connection portion to which a vacuum hose is connected. Since the slide core can be taken out after the slide core is taken out The operation was very inconvenient.

When a molded article having an undercut is taken out after molding, it is necessary to prevent the undercut portion from being caught by the mold and deformed at the time of taking out, and a simpler mold is required for the structure itself.

Korean Patent Registration No. 10-1454439 (undercut extraction device of injection mold) Korean Utility Model Laid-Open No. 20-2013-0001762 (an injection mold for manufacturing a product including an undercut) Korean Utility Model Publication No. 20-2015-0002220 (undercut rotary mold take-out device)

The present invention provides an injection mold having an undercut avoiding function that is easy to take out a product to a mold and has a simple structure for taking out by securing a releasing passage of a mold trapped in the product by physically elastically deforming the undercut of the molded product .

According to an aspect of the present invention, there is provided an injection mold having an undercut avoiding function. The injection mold includes: a stationary mold part for providing a supporting force; a stationary mold part having an upper core mounted on the stationary mold frame; A movable mold frame mounted on the movable mold frame and arranged in correspondence with the upper core in a state in which the movable mold frame is in tight contact with the stationary mold frame and having an undercut between the movable mold frame and the upper core; The core assembly being operated with the upper core open after the injection to cause the core assembly to push the undercut of the mold out of the core assembly, thereby preventing the mold core from interfering with the core assembly And a movable mold part having a core assembly driving part for allowing the movable mold part to be taken out without being received.

The core assembly may further comprise: A support core which is fixed to the movable mold frame and opens to the upper core side and in which a receiving space for providing a bottom part, a molding inner wall and an undercut forming part is formed; A molding core which is spaced apart from the molding inner wall and the undercut molding part by a predetermined distance while being inserted into the accommodation space so that the molding material is filled therebetween; And an undercut release inducing portion for separating the undercut formed between the forming core and the undercut forming portion from the molded core by pushing the undercut to the outside of the forming core.

Further, the formed core comprises: A core side surface portion corresponding to the molding inner wall, and a core bottom surface portion corresponding to the undercut molding portion, and the bottom surface thereof has a camco water space opened toward the bottom portion.

In addition, the undercut release inducing portion may include: A cam core which is provided at a lower portion of the forming core so as to be able to move up and down and is insertable into the camcorder water space in accordance with an up and down movement; And a plurality of slide cores horizontally moving in conjunction with a change in the gap of the cam core and pushing the undercuts positioned between the lower end surface of the core and the undercut forming part in the horizontal direction.

Further, a guide inclined portion is formed on the side of the cam core. A part of the slide core is slidably supported by the guide inclined portion, and receives a movement force generated by relative movement with the guide inclined portion Horizontal motion.

Further, the guide inclined portion of the cam core is inclined so as to horizontally move in the direction in which the slide core is opened when the molded core rises.

Further, the guide inclined portion of the cam core may be inclined so as to horizontally move in the direction in which the slide core is opened when the cam core rises.

The support core is further provided with a take-out block for raising the molded body so that the molded body is separated from the molded core in a state where the undercut of the molded body is opened outward by the core assembly.

The core assembly driving unit may further include: And a plurality of mil fins supported on the movable mold frame, the upper ends thereof being fixed to the molding core and the cam core, and lifting the molding core and the cam core.

The injection mold having the undercut avoiding function of the present invention as described above can physically and elastically deform the undercut of the molded product to secure the escape passage of the mold confined in the product so that the product can easily be taken out from the mold, The structure is simple.

1 is a view showing an example of an injection molding having an undercut.
2 is an overall perspective view of an injection mold having an undercut avoiding function according to an embodiment of the present invention.
3 is a sectional view taken along the line III-III in Fig.
Figs. 4 to 7 are views for explaining the configuration and operation principle of the core assembly shown in Fig. 3. Fig.
8 is a perspective view showing a cam core and a slide core which are coupled to each other together with a molded core.
9 is a perspective view for explaining the operation of the slide core shown in Fig.
10 is a cross-sectional view of another type of core assembly applicable to an injection mold according to an embodiment of the present invention.
11 is a sectional view showing the internal structure of the elastic holder shown in Fig.
Fig. 12 is a partially cutaway perspective view showing the operation principle of the inward pusher shown in Fig. 2;
FIGS. 13 to 16 are views for explaining the operation of the injection mold shown in FIG.

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

Basically, an injection mold according to this embodiment to be described later is a mold for manufacturing an injection mold having an undercut. As is known, the undercut formed in the injection molded product is an extraction interference member which is caught in the mold when the molded product is taken out of the mold. The undercut is caught by the mold and the injection can not be removed.

In order to extract an injection-molded article having an undercut portion from the mold in this way, the position of the mold was adjusted by leaving the injection-molded article as it is. In other words, moving the mold moves the mold away from the path of the undercut. In order to move the mold while the injection product remains in the mold, a very complicated structure must be applied, which causes a significant increase in the mold cost.

Unlike the conventional mold, the injection mold of the present embodiment has a structure for moving the undercut portion of the injection product to move the undercut away from the mold, instead of moving the mold. That is to say, it changes the movement path of the undercut in order to extract the injection product.

Fig. 1 shows an example of an injection molding having an undercut. The illustrated molded article A is also a product manufactured through an injection mold 10 to be described later.

As shown in the drawing, the undercut U is located at four places of the injection product A. The undercut (U) is the design of the injection itself. The injection mold of the present embodiment has a structure in which the mold core A 1 is formed from the molding core space A 1 to the molding core A. That is, It is possible to open the undercut U in the direction of the arrow z.

That is, the slide core 47, which will be described later, is horizontally moved in the direction of the arrow f in Fig. 6, the respective undercuts U are pushed in the direction of the arrow z, and the molds are taken out through the undercuts. In other words, the molded article is temporarily elastically deformed and taken out from the mold.

FIG. 2 is an entire perspective view of an injection mold 10 having an undercut avoiding function according to an embodiment of the present invention, and FIG. 3 is a sectional view taken along line III-III of FIG.

As shown in the figure, the injection mold 10 according to the present embodiment has a stationary mold portion 12 and a movable mold portion 20. The stationary mold portion 12 is fixed to a main frame (not shown) of the injection mold apparatus, and the movable mold portion 20 moves back and forth with respect to the stationary mold portion 12. The movable mold section 20 is in close contact with the stationary mold section 12 for the injection process and is spaced from the stationary mold section 12 in order to take out the manufactured injection mold.

The stationary mold part 12 has a stationary mold frame 12a, an upper core 14, and an injection nozzle 13. The fixed mold frame 12a is fixed to the main frame and supports the upper core 14. Further, the injection nozzle 13 introduces the flowable molding material supplied from the outside into the injection space B.

The upper core 14 is fixed to the stationary mold frame 12a and forms a molding frame with the core assembly 40 to be described later. An injection space B is formed between the upper core 14 and the core assembly 40 and a molding material is injected into the injection space B to mold the injection molding.

The movable mold part 20 includes a movable mold frame 20a, a core assembly 40, and a core assembly driving part 22. [ The movable mold frame 20a includes a base plate 21 in the form of a rectangular plate having a predetermined thickness, a support wall 23 vertically fixed to the upper portion of the base plate 21 and spaced apart from each other, And a guide block 25 fixed to the guide block 25.

The support wall 23 provides a space at the top of the base plate 21 and has an inwardly facing latch 23a at its inward face. As shown in FIG. 13A, the inward locking tab 23a acts as a stopper for preventing the bottom plate from climbing more than the end of the bottom plate.

The core assembly 40 corresponds to the upper core 14 in a state in which the movable mold frame 20a closely contacts the stationary mold frame 12a and has an injection space B with the upper core 14 . As mentioned above, the injection space B is a space filled with the flowable molding material supplied through the injection nozzle 13.

The core assembly 40 includes a support core 43, a molded core 41, and an undercut release guide portion. The undercut release inducing portion includes a cam core 45 and a slide core 47.

The base core 43 has a receiving space (43a in Fig. 5) as a member fixed to the movable mold frame 20a. The accommodating space 43a is opened upward as a space for accommodating the formed core 41, the cam core 45, and the slide core 47. [ An inner molding wall 43b, an undercut forming part 43c and a bottom part 43d are provided in the receiving space 43a.

The molding core 41, the cam core 45 and the slide core 47 are placed in the accommodating space 43a during the progress of the injection and are accommodated in the accommodating space 43a . The related matters will be described later.

The core assembly driving part 22 is for moving up and down the forming core 41 and the cam core 45 and includes a plurality of milling pins 53 and an upper plate 31 for supporting and lifting the milling pins 53, An intermediate plate 33, and a lower plate 35.

Some of the plurality of millefins 53 are fixed to the upper plate 31, the other part is fixed to the intermediate plate 33, and the remaining millefins are fixed to the lower plate 35, Since the lower end portions of the respective mine pins 53 are fixed to the mounters 31, 33, and 35, the mine pins 53 lift and lower in groups. That is to say, the group of the milifin fixed to the upper plate 31, the group of the milifin fixed to the middle plate 33, and the group of the milifin fixed to the lower plate 35 are raised and lowered separately.

The microneedle connected to the lower plate acts to raise or lower the cam core 45 vertically. The mille pin fixed to the intermediate plate 33 is connected to the forming core to raise the forming core 41, thereby playing the role of pushing the undercut in the direction of the arrow z in Fig.

Further, the mille pin fixed to the upper plate 31 separates the molded product from the molded core 41. The mille pin connected to the upper plate 31 also includes a mille pin 49a for raising the take-out block 49. As described above, the detailed configuration and operation of the up-and-down lifting plates 31, 33, and 35 for raising the milifin step by step will be described later with reference to FIGS.

Reference numeral 39 denotes an inward pusher. The inward pusher 39 is a member having a pushing surface 39a on the inside of the upper end portion thereof and pushes the lock king pin 56 provided on the lower push plate 35 inward, . This will be described later.

Reference numeral 55b denotes a connector. The connector 55b is a connecting part for connecting the intermediate plate 33 and the lower plate lifter 55. [ Reference numeral 37 denotes a resilient holder which connects the upper plate 31 and the lower plate 35. The pickup body 37a of the elastic holder 37 is resiliently coupled to the holding body 37f and separated by an external force. The description related to the elastic holder 37 will also be described later.

Reference numeral 61 denotes an upper plate pushing portion. The upper plate pushing portion 61 has a through rod 61a and an engaging bolt 61b. The through rod 61a is a hollow member having a predetermined diameter and penetrates through the base plate 21, the lower plate 35 and the intermediate plate 33 so that the upper end of the through rod 61a contacts the bottom surface of the upper plate 31. [ The penetrating rod 61a passes simply through the intermediate plate 33, the lower plate 35 and the base plate 21, and is not in a coupling relationship.

The coupling bolt 61b is a part that passes through the through rod 61a upwardly and is screwed to the upper plate 31. [ Therefore, when the through rod 61a is pressed in the direction of the arrow P, the upper plate 31 is vertically raised. At this time, when the upper plate 31, the intermediate plate 33, and the lower plate 35 are coupled to each other, the upper and lower plates 31, 33, 35 simultaneously rise.

Figs. 4 to 7 are views for explaining the configuration and operation principle of the core assembly 40 shown in Fig. 3. Fig. Fig. 4 shows a state immediately after injection, and Fig. 5 shows a state in which a molded core, a cam core, and a slide core are raised. 6 shows the state in which the slide core 47 is moved in the direction of the arrow z and the undercut U is released to the outside of the molded core and Fig. 7 shows the state in which the molded product A is completely separated from the molded core 41 FIG.

4, it can be seen that the molded core 41, the cam core 45, and the slide core 47 are accommodated in close contact with each other in the receiving space 43a of the receiving roller 43 have.

The molded core 41 has a core side surface portion 41a perpendicular to its outer surface and a camco water space 41b at the center of its bottom surface. The camcorder water space 41b is opened downward as a space for accommodating a part of the cam core 45. [ In addition, a core lower end surface portion 41c is located around the camcorder water space 41b. The core lower end surface portion 41c is a horizontal surface opposed to the undercut forming portion 43c.

As shown in Fig. 8, a plurality of core holders 41e are formed at the lower end of the formed core 41. As shown in Fig. The core holder 41e is a portion that receives and supports the protrusion 47c of the slide core 47. [ Each of the slide cores 47 is horizontally movable in the direction of the arrow z in Fig. 6 and the opposite direction thereof while being supported by the core holder 41e.

The cam core 45 and the slide core 47 are fitted to each other so as to be relatively movable with respect to each other, and have the structures shown in Figs. 8 and 9.

As shown in Figs. 8 and 9, the cam core 45 has a flat upper surface 45b and a bottom surface 45c, and has guide inclined grooves 45a on all four sides. The upper surface 45b is in contact with the molded core 41 and the lower surface is in contact with the bottom portion 43d of the receiving core 43.

The guide inclined grooves 45a are laterally opened grooves, and provide a linear ramp inclined inwardly from the upper surface 45b to the lower surface 45c. The inside mentioned above means the center portion of the cam core 45. Naturally, the width of the upper surface 45b is relatively larger than the width of the bottom surface 45c.

The slide core 47 has a pressing surface 47a, a sliding fit portion 47b, and a projection 47c, which move in the vertical direction with a part of the slide core 47 being fitted in the guide inclined groove 45a. As shown in Fig. 6, the pressing surface 47a pushes the undercut U portion in the direction of the arrow z.

Further, as shown in the drawing, the sliding fit portion 47b is fitted in the guide inclined groove 45a as a portion having a substantially T-shaped planar shape. The pressing surface 47a is reciprocated in the direction of the arrow z or in the opposite direction by sliding movement along the longitudinal direction of the guide inclined groove 45a in a state in which the sliding portion 47b is fitted in the guide inclined groove 45a Of course.

In addition, as described above, the slide core 47 is slidably supported by the core holder 41e through the protrusion 47c.

On the other hand, the forming inner wall 43b formed in the receiving core 43 corresponds to the above-mentioned core side portion 41a as a vertical wall facing the receiving space 43a. The core side portion 41a and the molding inner wall 43b are spaced apart to receive the molding material in a state where the molding core 41 is inserted into the accommodation space 43a.

The undercut forming portion 43c is a portion for forming the undercut U shown in Fig. 1 as a stepped portion formed at the lower end of the forming inner wall 43b. It goes without saying that the shape of the undercut forming portion 43c varies according to the shape of the undercut. The undercut forming portion 43c corresponds to the bottom surface of the core lower end surface portion 41c. It goes without saying that the shape of the undercut molding portion is reflected in the molding material injected between the core bottom face portion 41c and the undercut molding portion 43c.

The bottom portion 43d is a supporting surface for supporting the cam core 45. The cam core 45 closely adheres to the camcorder water space 41b and the bottom surface of the accommodation space 43a to stably maintain the gap of the formed core 41 relative to the base core 43. [

In addition, a plurality of take-out blocks 49 are provided around the forming core 41. The take-out block 49 is a member that supports the edge portion of the frame A, and is lifted up by the take-out mil pin 49a.

The take-out of the molded article A through the core assembly 40 having the above-described configuration is carried out as follows.

First, when the movable mold part 20 is separated from the stationary mold part 12 after the injection is completed, the molded article A is exposed to the outside, as shown in Fig. The injection product A covers the upper portion of the support core 43 and the formed core 41.

The mold core 41 and the cam core 45 are raised to the upper portion of the accommodation space 43a in order to separate and take out the molded article A from the core assembly 40. [ For this purpose, it is a matter of course that the up-and-down platforms 31, 33, 35 and the miliphin 35 must rise.

5, it can be seen that the molded article 41 and the cam core 45 are released to the upper portion of the containing space 43a, whereby the molded article A is completely separated from the containing space 43a. However, the undercut U of the molded product A is caught at the lower end of the molded core 41, that is, the core lower end face portion 41c. Therefore, in this state, even if the take-out block 49 is pushed upward, the molded article A is not separated from the molded core 41.

In order to take out the molded article A, the molded core 41 is further raised in the state of Fig. At this time, the cam core 45 is not elevated but maintains its height.

Each of the slide cores 47 supported by the core holder 41e rises along the guide inclined grooves 45a while the formed core 41 is lifted while the cam core 45 is fixed, Direction. With the movement of the slide core 47, the undercut U is pushed by the slide core and escapes outward from the core lower end surface portion 41c. After the undercut U is separated from the core lower end surface portion 41c, the molded article A can be taken out to the vertical upper portion.

That is, as shown in Fig. 7, the takeout block A can be completely separated from the molded core 41 by raising the takeout block 49 completely. While the take-out block 49 is lifted up, the surrounding mil fins 53 also rise, and another part of the injection product A is taken out to the upper part.

10 is a cross-sectional view illustrating another type of core assembly 40 applicable to an injection mold according to an embodiment of the present invention.

As shown in Fig. 10, a cam core 46 different from the above-described cam core 45 may be applied to the injection mold 10. In the cam core 46 shown in Fig. 10, the oblique direction of the guide oblique grooves 46a is opposite to the guide oblique grooves 45a. That is, when the cam core 46 moves upward, the slide core 47 moves in the direction of the arrow z. The cam core 46 is the same as the cam core 45 of Fig. 8 except for the direction of the guide inclined groove 46a.

11 is a sectional view showing the internal structure of the elastic holder 37 shown in Fig.

The elastic holder 37 serves to elastically connect the upper plate 31 and the intermediate plate 33. For example, when the upper plate 31 is lifted up, it is lifted up along the middle plate 33.

The elastic holder 37 includes a pickup body 37a fixed to the side of the upper plate 31, a holding body 37f fixed to the side of the intermediate plate 33, a pressing ball 37k, Respectively.

The pickup body 37a takes a substantially T shape and has a fixing portion 37b and an insertion portion 37c. The fixing portion 37b is a portion that is fixedly coupled to the upper plate 31 and the insertion portion 37c is a portion extending vertically downwardly integrally with the fixing portion 37b. A ball groove 37d is formed on both sides in the width direction of the insertion portion 37c. The ball groove 37d is a groove for receiving and supporting the pressing ball 37k.

The holding body 37f takes the form of a U-shape and receives and supports the insertion portion 37c in a state where both ends of the holding body 37f are fixed to the side of the intermediate plate 33. [ A spring mounting groove 37h is formed inside the holding body 37f. The spring mounting groove 37h is a groove for receiving the spring. The spring 37m elastically presses the pressing ball 37k while being accommodated in the spring mounting groove 37h so that the pressing ball 37k is elastically held in the ball groove 37d.

The coupling between the pick-up body 37a and the holding body 37f is maintained by the spring 37m and the pressurizing ball 37k, and is separated when a certain strong force is applied. The pickup body 37a is lifted up by the holding body 37f when the intermediate plate 33 is caught somewhere and can no longer be lifted up while the upper plate 31 and the intermediate plate 33 are in close contact with each other. And is drawn out from the through passage 37g. In some cases, the upper plate 31 and the intermediate plate 33 can be separated.

12 is a partially cutaway perspective view showing the operation principle of the inward pusher 39 shown in Fig.

The inward pusher 39 is a member provided on the opposite side across the stack of the upper and lower plates 31, 33 and 35, and has a coupling portion 39b and a vertical extension portion 39c. The engaging portion 39b is a portion that is bolted to the mounting groove 21a of the base plate 21. The vertical extension portion 39c is a member extending vertically to the base plate 21 and integrally formed with the base plate 21 and has a pushing surface 39a at its upper inward surface.

The pushing surface 39a pushes the lock king pin 56 in the direction of arrow d when the lower plate 35 is lifted and pushes the lock king pin 56 outwardly of the receiving jaw 55a as shown in Fig. It plays a role. That is, the lock pin 56 is separated from the base 55a so that the base 55a is not supported by the bottom plate lifter 55 any more. The reason for this will be described later. The angle of the pushing surface 39a with respect to the vertical line may be varied as needed.

In addition, the lower plate lifter 55 is installed on both sides of the vertical extension portion 39c. The lower plate lifter 55 has a vertical rod 55c and a connector 55b. The vertical rod is a rod-like member extending in the vertical direction, and has a base end 55a at its lower end. The pedal jaw 55a is located at the lower end of the lock king pin 56 and is a latch portion for supporting the lock king pin 56.

The connector 55b is a connecting part that connects the vertical rod 55c to the side of the intermediate plate 33. [ It goes without saying that the lower plate lifter 55 simultaneously ascends and descends as the intermediate plate 33 ascends and descends. For example, when the lock pin 56 is hooked on the base jaw 55a, a lifting force is applied to the connector 55b, the vertical rod 55c, and the base jaw 55a And is transmitted to the lock pin 56 in order. The lock pin 56 also ascends.

The locking pin 56 is a plate-shaped member having a predetermined thickness and is provided on the side of the lower plate 35 so as to be slidable in the direction of the arrow d in FIG. 14B and the opposite direction. In addition, two spring grooves 56a are formed at one end of the lock king pin 56. The spring groove 56a is a groove into which the spring 57 is fitted. The spring 57 functions to press the locking pin 56 toward the lower plate lifter 55 in a state where a part of the spring 57 is fitted in the spring groove 56a.

FIGS. 13 to 16 are views for explaining the operation of the upper plate 31, the intermediate plate 33 and the lower plate 35 in the injection mold shown in FIG.

As described above, a plurality of milling pins 53 are vertically fixed to the upper plate 31, the intermediate plate 33, and the lower plate 35. The upward and downward buckling plates (31, 33, 35) are raised and lowered to indicate that the pinching plate is fixed to each plate.

The mold pin 53 fixed to the intermediate mold 33 of the mold pin firstly lifts the mold core 41 and the mold pin 53 supported by the intermediate mold plate 35 lifts the mold core secondarily, The above-mentioned method of separating the molded article (A) from the molded core (41) by the third rising of the milipine fixed to the upper plate (31) has been mentioned above.

In the present embodiment, the inward pusher 39 and the lower plate lifter 55 shown in FIG. 12 and the lower plate lifter 55 shown in FIG. The indicated gap retaining bolts 36 were applied.

15B, it can be seen that the gap maintaining bolt 36 is screwed to the intermediate plate 33 while being inserted upward into the bolt installation hole 35a formed in the lower plate 35 have. That is, the head portion 36a of the gap retaining bolt 36 is provided so as to be vertically movable in the bolt mounting hole 35a, and the screw portion 36b is coupled to the intermediate plate 33. [

Therefore, when the intermediate plate 33, which was in close contact with the lower plate 35, is lifted up, the head portion 36a is caught by the head latch jaw 35b, 36 are raised together. Thereafter, the intermediate plate 33 and the lower plate 35 are kept at a constant interval.

In other words, when the intermediate plate 33 and the lower plate 35, which are in close contact with each other and are lifted together, are stopped, the head plate 36a is closed It can be further raised until it is caught by the jaw 35b.

Referring to FIGS. 13A and 13B, it can be seen that the upper and lower heavy plates 31, 33, and 35 are all lowered and closely contacted with each other. This state is immediately after the completion of the injection and the locking pin 56 is caught by the support pin 55a by the action of the spring 57 and the head portion 36a of the gap retaining bolt 36 is engaged with the bolt installation hole 35a. The pickup body 37a of the elastic holder 37 is supported by the spring 37m and the pressing ball 37k in a state of being fitted in the holding body 37f.

In order to take out the molded article A from the above state, the upper plate 31 is pushed up in the direction of the arrow P through the upper plate pushing portion 61. Even when the upper plate 31 rises, the upper and lower plates 31, 33, and 35 are coupled to each other. Reference numeral 51 denotes a guide rod for guiding the vertical lift movement of the upper and lower lower plates 31, 33, 35.

While the lifting plates 31, 33, and 35 are moving upward, the locking pin 56 is pushed in the direction of the arrow d by touching the pushing surface 39a (as shown in FIGS. 14A and 14B) . When the upper plate pushing portion 61 is further raised in this state, the lock pin 56 completely disengages from the plate stop 55a, and at the same time, the end of the lower plate 35 is hooked on the inward locking tab 23a. Thereafter, the lower plate 35 can no longer rise.

The moment when the lower plate 35 is caught by the inwardly engaging jaw 23a, the core assembly 40 is in the state shown in Fig. That is, the molded core 41, the cam core 45, and the slide core 47 are moved upward from the receiving space 43a of the receiving core 43.

When the upper push plate pushing portion 61 is continuously elevated after the lower push plate 35 is stopped, the upper push plate 31 and the intermediate push plate 33 further rise. At this time, the intermediate plate 33 is separated from the lower plate 35. The further upward movement of the upper plate 31 and the intermediate plate 33 continues until the head portion 36a reaches the head latch jaw 35b.

The stopper of the lower plate 35 and the further upward movement of the upper plate 31 and the intermediate plate 33 bring the state of the core assembly 40 to the state shown in Fig. That is, the molded core 41 further rises in a state where the cam core 45 is fixed, and as a result, the slide core 47 moves in the direction of arrow z and the undercut U is moved from the core lower end surface portion 41c .

When the upper plate pushing portion 61 is fully raised in this state, the upper plate 31 is separated from the intermediate plate 33 and reaches the bottom of the guide block 25, as shown in FIG. In this case, the pickup body 37a is separated from the holding body 37f.

As shown in Fig. 7, by the rise of the upper plate, a large number of the millefins 53 and the take-out block 49 ascend and completely separate the molded article A from the molded core 41. [ The separated extrudate A is taken out and transferred to a subsequent process line.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

10: injection mold 12: stationary mold part 12a: stationary mold frame
13: injection nozzle 14: upper core 20: movable mold part
20a: movable mold frame 21: base plate 21a: mounting groove
22: core assembly driving part 23: support wall 23a: inwardly engaging jaw
25: guide block 31: upper plate 33: intermediate plate
35: Lower plate 35a: Bolt mounting hole 35b: Head catching jaw
36: spacing retaining bolt 36a: head portion 36b:
37: elastic holder 37a: pick-up body 37b:
37c: insertion portion 37d: ball groove 37f: holding body
37g: Through passage 37h: Spring mounting groove 37k: Pressurized ball
37m: spring 39: inward pusher 39a: pushing face
39b: coupling portion 39c: vertical extension portion 40: core assembly
41: Molded core 41a: Core side part 41b: Kamokor water space
41c: core lower end surface portion 41e: core holder 43:
43a: accommodation space 43b: molding inner wall 43c: undercut molding part
43d: bottom part 45: cam core 45a: guide inclined groove
45b: upper surface 45c: bottom surface 46: cam core
46a: guide inclined groove 47: slide core 47a: pressing face
47b: sliding fit portion 47c: projection portion 49: extraction block
49a: Milfin pin 51: Guide rod 53:
55: lower spille pin lifter 55a: support pin 55b: connector
55c: vertical load 56: lock kingpin 56a: spring groove
57: spring 61: upper plate pushing portion 61a: through rod
61b: coupling bolt

Claims (9)

delete delete A stationary mold part having a stationary mold part and a stationary mold part;
A movable mold frame mounted on the movable mold frame and arranged in correspondence with the upper core in a state in which the movable mold frame is in tight contact with the stationary mold frame and having an undercut between the movable mold frame and the upper core; The core assembly being operated with the upper core open after the injection to cause the core assembly to push the undercut of the mold out of the core assembly, thereby preventing the mold core from interfering with the core assembly And a movable mold part having a core assembly driving part for allowing the movable mold part to be taken out without being received,
The core assembly comprising:
A supporting core which is fixed to the movable mold frame and opens to the upper core side and in which a receiving space for providing a bottom part, a molding inner wall and an undercut forming part is formed,
A forming core which is provided so as to be able to move up and down in the receiving space of the base core and is spaced apart from the forming inner wall and the undercut forming part while being inserted into the accommodating space so that the molding material is filled therebetween;
And an undercut releasing guide portion provided at a lower portion of the forming core and separating the undercut formed between the forming core and the undercut forming portion from the molding core by pushing the undercut to the outside of the forming core, / RTI >
The forming core comprising: a core side portion corresponding to the molding inner wall; And an undercut avoiding function having a cavity bottom surface portion opened to the bottom portion on a bottom surface thereof, the bottom surface portion corresponding to the undercut forming portion. The method of claim 3,
Wherein the undercut releasing inducing portion comprises:
A cam core which is provided at a lower portion of the forming core so as to be able to be elevated and lowered and which can be inserted into the camcorder water space in accordance with the upward /
And an undercut located between the lower end surface of the core and the undercut forming part, wherein the lower end of the undercut forming part is in sliding contact with the side surface of the cam core, And a plurality of slide cores for pushing the plurality of slide cores in a horizontal direction. 5. The method of claim 4,
A guide inclined portion is formed on a side portion of the cam core,
Wherein the slide core is partly slidably supported by the guide inclined portion and has an undercut avoiding function that is horizontally moved by receiving a movement force generated by a relative movement with the guide inclined portion. 6. The method of claim 5,
Wherein the guide inclined portion of the cam core has an inclined undercut avoiding function for causing the slide core to horizontally move in a direction in which the slide core 6. The method of claim 5,
Wherein the guide inclined portion of the cam core has an inclined undercut avoidance function such that the slide core horizontally moves in a direction in which the slide core extends when the cam core rises. The method of claim 3,
In the base core,
And a take-out block for allowing the molded body to be separated from the molded core by raising the molded body while the undercut of the molded body is opened outward by the core assembly. The method of claim 3,
The core assembly driving unit includes:
And an undercut avoiding function including a plurality of mill pins which are supported by the movable mold frame and whose upper ends are fixed to the forming core and the cam core and which elevate the forming core and the cam core.

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