KR20230055057A - A moulding for a product with undercut - Google Patents

Abstract

The present invention relates to a mold having an undercut for molding a product, which comprises: a first mold (10) having a first core (12) with an engraved molding surface; a second mold (20) having a second core (22) with an embossed molding surface corresponding to the engraved molding surface of the first mold (10); a plurality of slide split cores (30) interposed between the first core (12) and the second core (22) and split into the plurality of the cores to surround the circumference of the proximal end of the second core (22) with the undercut (P') of a product (P), wherein concave grooves (31) that are concave inward and extend from the first core (12) toward the second core (22) are aligned on the sides of both ends adjacent to each other; an inclined pin (40) disposed in the second mold (20) to guide the slide split cores (30); a core push pin (50) disposed in the second mold (20) to push each slide split core (30) toward the first mold (10) while each slide split core (30) is engaged with the undercut (P') of the product (P) when the first and second molds (10, 20) are separated; a connection plate (60) connecting a pair of the core push pins (50) that push the slide split cores (30) adjacent to each other; and a core alignment means (70) including a fixing piece (71) surrounding the end portion of each side of the pair of the slide split cores (30) adjacent to each other and a fixing bolt (72) penetrating the concave grooves (31) of the pair of the slide split cores (30) to fix the fixing piece (71) to the connection plate (60). Accordingly, the slide split cores (30) can be easily maintained and replaced.

Description

A molding for a product with undercut}

The present invention relates to a mold for molding an undercut product, and more particularly, to a mold for molding an undercut product for molding an undercut product.

In general, a mold is used to manufacture a predetermined article from synthetic resin. The mold is composed of a first mold with a first core and a second mold with a second core, but a slide core is added when there is an undercut in the product to be manufactured. As is well known, the slide core is guided by an inclined pin provided in the first mold and retreats laterally from the product in the process of separating the first mold from the second mold.

On the other hand, well-known pail containers are molded using the mold described above. The first core of the first mold is convex and the second core of the second mold is concave, and a slide core is formed between the first and second cores. installed The slide core is divided into a plurality of slide dividing cores, and pin insertion grooves extending inwardly are aligned with each other on the side surfaces of the slide dividing cores adjacent to each other. Then, a fixing pin is inserted into the pin insertion groove of the slide dividing core adjacent to each other to fix the plurality of slide dividing cores to each other.

However, in the conventional mold, since a plurality of slide dividing cores are fixed by respective fixing pins to form a circular shape, in order to maintain or replace one of the plurality of slide dividing cores, a plurality of slide dividing cores are fixed to each other. There is a problem in that the slide dividing core can be separated only when all of the two fixing pins are separated. Accordingly, there is a problem in that the maintenance and replacement work of the slide dividing core is cumbersome.

Korea Utility Model Registration No. 20-0441694

The present invention is to solve the problems as described above, and an object of the present invention is to stably fix a plurality of slide dividing cores and easily separate only required slide dividing cores without separating other slide dividing cores. It is easy to maintain and replace the split core, and in addition, when taking out the molded product, local load is prevented from being applied to the product, so that the product is prevented from being damaged by the local load. Provide a mold for product molding with an undercut formed is in doing

According to a feature of the present invention, in the mold for molding a product (P) formed with an undercut (P'), the first mold (10) provided with a first core (12) on which the intaglio molding surface is formed; a second mold 20 having a second core 22 having an embossed surface corresponding to the intaglio molding surface of the first mold 10; It is located between the first core 12 of the first mold 10 and the second core 22 of the second mold 20, but is divided into a plurality of parts to form an undercut P' of the product P A plurality of concave grooves 31 are arranged around the proximal end of the second core 22 and are concave inward on both end side surfaces adjacent to each other and extending from the first core 12 to the second core 22. Slide dividing core 30; an inclined pin (40) provided in the second mold (20) protruding toward the first mold (10) and guiding the slide dividing core (30) by being inclined outward toward the tip; It is provided in the second mold 20, and when the first and second molds 10 and 20 are separated, each slide dividing core 30 is engaged with the undercut P' of the product P Core mill pins 50 for pushing each slide dividing core 30 toward the first mold 10; a connecting plate 60 connecting a plurality of core mill pins 50 respectively pushing the slide dividing core 30 adjacent to each other; And a fixing piece 71 surrounding the end of each side of a pair of slide dividing cores 30 adjacent to each other in contact with the first core 12, and a concave groove of the pair of slide dividing cores 30. A mold for molding a product having an undercut, characterized in that it includes; a core aligning means (70) including a fixing bolt (72) passing through (31) and fixing the fixing piece (71) to the connecting plate (60). is provided.

According to another feature of the present invention, at both ends of the upper surfaces of the slide dividing cores 30 adjacent to each other, seating grooves 32 with open sides are further formed so that the fixing pieces 71 of the core aligning means 70 are seated. There is provided a mold for forming a product having an undercut, characterized in that.

According to another feature of the present invention, the connecting plate 60 connects the ends of a pair of core mill pins 50 so as to come into contact with the slide dividing core 30 to form the slide dividing core 30 into the first mold 10 ) There is provided a mold for molding a product having an undercut, characterized in that it is pushed toward the side.

As described above, according to the present invention, the core aligning means 70 for aligning a pair of slide dividing cores 30 adjacent to each other among the plurality of slide dividing cores 30 is the first core of the first mold 10. The fixing piece 71 supporting one surface of the pair of slide dividing cores 30 facing (12) and the fixing piece passing through the concave groove 31 formed at the end of the slide dividing core 30 It consists of a fixing bolt 72 for fixing (71). Accordingly, when one slide dividing core 30 is separated for maintenance or replacement, there is no need to separate all other core aligning means 70 for aligning the remaining slide divided cores 30, and the required core alignment is required. Since only the fixing piece 71 of the means 70 needs to be easily separated, maintenance and replacement work of the slide dividing core 30 is easy.

And since the seating groove 32 in which the fixing piece 71 of the core aligning means 70 is seated is formed at one end of one surface of the slide dividing core 30, the first core 12 of the first mold 10 slides. It can be more closely attached to the split core 30, so the quality of the product is improved.

In addition, the connecting plate 60 connecting the ends of the pair of core mill pins 50 pushing the slide dividing core 30 adjacent to each other is in contact with the slide dividing core 30 to directly push the slide dividing core 30 Therefore, the slide dividing core 30 is pressed against the connection plate 60, which has a relatively large area compared to the tip of the core mill pin 50, and the slide dividing core 30 is prevented from being damaged.

1 is a view showing an embodiment of a mold for molding a product having an undercut according to the present invention;
Figure 2 is a perspective view showing the slide dividing core of the embodiment
3 is a view showing the positional relationship between the slide dividing core and the core aligning means in FIG. 2;
4 is a view showing the operation of the core mill pin of the above embodiment
5 is a view showing the operation of the slide dividing core of the above embodiment
6 is a view showing product withdrawal of the embodiment

Objects, features and advantages of the present invention described above will become more apparent through the detailed description that follows. Hereinafter, a preferred embodiment of the present invention will be described based on the accompanying drawings.

1 to 6 are diagrams showing a mold for forming a product having an undercut according to an embodiment of the present invention. As shown, the mold for molding a product having an undercut according to an embodiment of the present invention includes a first mold 10 having a first core 12 and a second mold having a second core 22 (20), a slide dividing core (30) that is divided into a plurality of parts and wraps around the proximal end of the second core (22), an inclined pin (40) for guiding the slide dividing core (30), and the second mold ( 20) and a plurality of core mill pins 50 for pushing each slide dividing core 30 toward the first mold 10, and a connection plate 60 connecting a pair of adjacent core mill pins 50, , It is coupled to the connecting plate 60 and includes a core aligning means 70 for aligning a pair of adjacent slide dividing cores 30.

The first mold 10 includes a fixed side plate 11 and a first core 12 provided on one surface of the fixed side plate 11 . At this time, an intaglio molding surface is formed on the first core 12 . A resin inlet 13 for injecting resin into the first core 12 is formed on the bottom surface of the first core 12 . In addition, a receiving groove 14 in which the inclined pin 30 is accommodated is formed on the side of the intaglio molding surface of the first core 12 .

The second mold 20 is molded with the first mold 10, and includes a movable side plate 21 and a second core 22 provided on one surface of the movable side plate 21. An embossed surface is formed on the second core 22, and the embossed surface has a shape corresponding to the intaglio surface of the first core 12 of the first mold 10, so that the second core 22 is 1 is inserted into the core 12. At this time, as shown in FIG. 1 , the proximal end of the second core 22 is exposed without being inserted into the first core 12 .

In the illustrated embodiment, the first and second cores 12 and 22 are configured to have a circular cross section to mold a product P having a shape such as a well-known pail container. On the other hand, the second core 22 of the second mold 20 is formed with a take-out pin 24 for completely taking out the product P from the second core 22 or an aero for taking out air. In addition, a plurality of guide passages 23 through which the core mill pins 50 are moved are formed in the second mold 20 back and forth.

The plurality of slide dividing cores 30 are divided into a plurality of pieces so as to surround the exposed base end of the second core 22 of the second mold 20, and the slide dividing core 30 and the first and second cores 22 are formed separately. The inner space formed by the two cores 12 and 22 forms a cavity into which resin is injected. At this time, a molding surface having a shape corresponding to the shape of the undercut (P') of the product (P) is formed on the inner surface of the slide dividing core (30).

Although the slide dividing core 30 may be divided into two or more, the length separated from the undercut P' of the product P guided by the inclined pin 40 is short, so that the undercut P' It is preferable to divide into four parts in consideration of ease of manufacture while minimizing damage to the part. Accordingly, the slide dividing core 30 is formed in an arc shape having a dividing angle of 90 degrees.

Here, the surface facing the first core 12 of the slide dividing core 30 is defined as the front, and the slide dividing core 30 will be described. As shown in FIG. 3, concave grooves 31 that are concave inward and extend forward and backward are aligned on opposite sides of the slide dividing core 30 adjacent to each other.

In addition, a pin guide hole 33 through which the inclined pin 40 passes is formed in the slide dividing core 30 . At this time, the inclined pins 40 are provided at a distance of two for each slide dividing core 30, and the pin guide holes 33 are also formed at a distance of two at a time. Accordingly, the slide dividing core 30 is more stably guided by the inclined pin 40 .

The inclined pin 40 is installed in the second mold 20 and is installed on the side of the embossed surface of the second core 22. Such an inclined pin 40 protrudes toward the first mold 10 and is installed in an outwardly inclined form toward the tip, so that when the second mold 20 is separated from the first mold 10, the slide dividing core ( 30) to guide the movement.

The core mill pin 50 pushes the slide dividing core 30 toward the first mold 10 through the guide passage 23 of the second mold 20 . The core mill pin 50 is made of a cylinder and pushes the slide dividing core 30 when the second mold 20 is separated from the first mold 10. Accordingly, as the slide dividing core 30 engaged with the undercut P' of the product P moves, the product P itself is pushed toward the front end of the second core 22, so that the product P moves to the second core 22. separated from the core 22.

On the other hand, as shown in FIG. 4, the guide passages 23 of the second mold 20 are exemplified by being spaced apart by two for each slide dividing core 30, and each slide dividing core 30 includes two core mill pins 50. ) was exemplified by being pushed out. Accordingly, the slide dividing core 30 is more stably pushed by the two core mill pins 50 spaced apart from each other.

It is preferable that the core mill pin 50 is operated at the same time as the second mold 20 is separated from the first mold 10. At this time, such simultaneous operation may be controlled through a control unit (not shown). Meanwhile, the plurality of core mill pins 50 may be configured to be guided by the guide block 80.

The connecting plate 60 connects a pair of core mill pins 50 pushing the slide dividing core 30 adjacent to each other.

The mold for forming products having an undercut according to an embodiment of the present invention may be configured to connect the ends of a pair of core mill pins 50 so that the connecting plate 60 contacts the slide dividing core 30 . Accordingly, since the connecting plate 60 directly pushes the slide dividing core 30 toward the first mold 10, the area of the connecting plate 60 is wider than the area of the front end of the core mill pin 50, so that the slide dividing Since local loads are prevented from being concentrated on the core 30, damage to the slide split core 30 is prevented, and durability is improved.

As shown in FIGS. 2 and 3, the core aligning means 70 includes a fixing piece 71 for supporting the front surfaces of opposite ends of a pair of adjacent slide split cores 30, and the fixing piece 71. It includes a fixing bolt 72 for fixing to the connecting plate 60. At this time, the fixing bolt 72 passes through the concave groove 31 of the pair of adjacent slide dividing cores 30 and is fixed to the connecting plate 60. Preferably, the connection plate 60 may be provided with a support bar 73 having a female thread and passing through the concave groove 31 of the slide dividing core 30 to support the fixing piece 71, and a fixing bolt (72) can be screwed to the support bar (73). The plurality of slide dividing cores 30 can be moved together by the core aligning means 70 .

In this way, since the fixing piece 71 of the core aligning means 70 is located in front of the slide dividing core 30, it is possible to separate any one of the slide dividing cores 30 adjacent to each other. For this, only the fixing piece 71 supporting the adjacent slide dividing core 30 needs to be separated. Accordingly, since there is no need to separate the fixing piece 71 of the entire core aligning means 70 for maintenance and replacement of one slide split core 30, maintenance and replacement work is easy and maintenance and replacement There is an advantage in that it is easy to reassemble the slide dividing core 30.

In the mold for forming products having an undercut according to an embodiment of the present invention, a seating groove 32 may be further formed at an end portion of the front surface of the slide dividing core 30 . The fixing piece 71 of the core aligning means 70 is seated in the seating groove 32, and because of this, the fixing piece 71 does not protrude from the slide dividing core 30, so that the first mold 10 The quality of the product is improved because the single core 12 is in close contact with the slide dividing core 30.

The operation of the mold for forming a product having an undercut according to an embodiment of the present invention configured as described above will be described as follows.

As shown in FIG. 1, the first mold 10 and the second mold 20 are molded together, and the slide dividing core 40 is assembled so that the inclined pin 30 penetrates. Then, the resin is injected into the cavity through the resin inlet 13 and cured. Accordingly, the product P having the undercut P' formed thereon is molded.

Then, as shown in FIG. 4, the second mold 20 is separated from the first mold 10. At this time, as shown in FIGS. 4 and 6, the core mill pin 50 is operated to push the slide dividing core 40 toward the first mold 10. Accordingly, as shown in FIG. 6, as the slide dividing core 40 is pushed toward the first mold 10 in a state of being engaged with the undercut P' of the product P, the product P is removed from the second core 22. Separated. That is, when the slide split core 40 is pushed by the core mill pin 50, the product P is pulled toward the front end of the second core 22, that is, toward the first mold 10, so that the product P is It is separated from the two cores 22 as shown in FIG. 2, and is completely separated from the second core 22 by the take-out pins 24. At this time, since the connecting plate 60 connecting the tip of the core mill pin 50 of the adjacent slide dividing core 30 comes into contact with the slide dividing core 30 and directly pushes it, the slide dividing core 30 has a core mill pin. The local load applied by the front end of (50) is reduced and the slide dividing core (30) is prevented from being damaged.

The present invention described above is not limited by the foregoing embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible within a range that does not deviate from the technical spirit of the present invention. will be clear to those who have knowledge of

P : Product P' : Undercut
10: first mold 12: first core
20: second mold 22: second core
23: guide passage 30: slide dividing core
31: concave groove 32: seating groove
40: inclined pin 50: core mill pin
60: connection plate 70: core alignment means
71: fixing piece 72: fixing bolt

Claims (3)

In the mold for molding the product (P) in which the undercut (P') is formed,
A first mold 10 having a first core 12 having an intaglio molding surface formed thereon;
a second mold 20 having a second core 22 having an embossed surface corresponding to the intaglio molding surface of the first mold 10;
It is located between the first core 12 of the first mold 10 and the second core 22 of the second mold 20 and is divided into a plurality of parts to form an undercut P' of the product P A plurality of concave grooves 31 are arranged around the proximal end of the second core 22 and are concave inward on both end side surfaces adjacent to each other and extending from the first core 12 to the second core 22. Slide dividing core 30;
an inclined pin (40) provided in the second mold (20) protruding toward the first mold (10) and guiding the slide dividing core (30) by being inclined outward toward the tip;
It is provided in the second mold 20, and when the first and second molds 10 and 20 are separated, each slide dividing core 30 is engaged with the undercut P' of the product P a core mill pin 50 pushing each slide dividing core 30 toward the first mold 10;
At least a connection plate 60 connecting the plurality of core mill pins 50 pushing the slide dividing core 30 adjacent to each other, respectively; and
A fixing piece 71 surrounding an end of each surface of a pair of slide dividing cores 30 adjacent to each other in contact with the first core 12, and a concave groove of the pair of slide dividing cores 30 ( 31) and a core aligning means (70) including a fixing bolt (72) for fixing the fixing piece (71) to the connecting plate (60). The method of claim 1, characterized in that seating grooves 32 with side openings are further formed at both ends of the upper surfaces of the slide dividing cores 30 adjacent to each other so that the fixing pieces 71 of the core aligning means 70 are seated. A mold for product molding with an undercut formed by The method of claim 1 or 2, wherein the connecting plate (60) connects the ends of a pair of core mill pins (50) so as to come into contact with the slide dividing core (30) to form the slide dividing core (30) into the first mold ( 10) A mold for molding a product having an undercut, characterized in that it is pushed toward.

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