JP2009051036A - Undercut processing mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an undercut processing mechanism capable of dealing with requirement of space saving by being configured compactly, realizing cost reduction, in particular, and dealing with a molded article of a complicated form having multiple undercut parts radially positioned in the whole circumferential direction of the molded article. <P>SOLUTION: Three or more slide members 70 are housed in a holder 40 in a radial shape that the slide members 70 are opposed to a holder center axis. Each slide member 70 is slidably housed in the holder to be slidablr between a molding position, where the respective ends are made in contact with each other inside the holder 40, and a position, where the respective ends separate are made away from each other outside the holder. A tilted groove 44 is provided in the holder, serving as guides guiding the respective slide members 70 toward the mold releasing position from the molding position when mold cutting a molded article P, in the mold cutting direction parallel to a holder central axis and in the escaping direction from an undercut part P1 which is the radial direction of the holder central axis, along the tilted direction moving simultaneously respectively. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an undercut processing mechanism that enables an undercut portion to be removed when a molded product having a undercut portion is molded by a fixed die and a movable die when the molded product is die-cut.

  Conventionally, as this type of molding die device, a guide rod in which a movable loose core support rod penetrating the core and inclined with respect to its surface is locked to the movable side mold plate and the pedestal plate is used. In the loose core ejector device that is linked to the movement of the slide base disposed in the slide path of the ejector plate so as to be slidable relative to the guide plate, one end of the guide rod is in a recess formed on the lower surface of the movable side template. It is known that the loose core support rod is locked by a tightly fitted holder and the inclination angle is set only by an angle setting hole formed in the core at substantially the same inclination angle as the guide rod (for example, , See Patent Document 1).

JP 2002-326233 A

  However, in the conventional technique as described above, not only the loose core support rod but also the guide rod are inclined, and the mechanism for moving the rod at the same inclination angle is the ejector plate and the movable side plate. Because it is configured to disperse into a large amount of space, it requires a large installation space compared to the amount of movement of the piece with the undercut part shape necessary for removing the undercut of the molded product, and the structure becomes complicated overall. Assembling took time and effort, and it was difficult to reduce costs.

  Further, it can only cope with the case where the undercut portion is in one direction of the outside or inside of the molded product, for example, there are a plurality of undercut portions that are located radially over the entire circumferential direction of the molded product. In some cases, it was impossible to die-cut such a molded product. Therefore, in addition to the number of undercut portions in the moldable molded product, there is a problem that the position and shape are limited to a very narrow range.

  The present invention has been made paying attention to the problems of the prior art as described above, can be configured compactly, can meet the demand for space saving, and can be processed and incorporated into a mold. Is easy to construct, has a simple structure, does not require time and effort to assemble, and can reduce costs. In particular, a plurality of undercut portions that are located radially over the entire circumference of the molded product An object of the present invention is to provide an undercut processing mechanism that can easily cope with a molded product having a complicated shape.

The gist of the present invention for achieving the object described above resides in the inventions of the following items.
[1] Mold apparatus (20, 20A) for molding a molded product (P, P2) having an undercut portion (P1, P3) with a fixed mold (11, 11A) and a movable mold (12, 12A) In the undercut processing mechanism (30, 30A) that allows the undercut portions (P1, P3) to be removed when the molded product (P, P2) is die-cut,
The holder (40, 40A) disposed in the fixed mold (11, 11A) or the movable mold (12, 12A), and three or more in the holder (40, 40A) face the holder central axis. A slide member (70, 70A) stored radially, and an undercut molding part (80, 80A) provided at a portion of each slide member (70, 70A) facing each other,
Each slide member (70, 70A) has a molding position where the tip portions thereof are in contact with each other in the holder (40, 40A), and a separation position where the tip portions are separated from each other outside the holder (40, 40A). It is stored in the holder (40, 40A) so as to be slidable to the mold position,
In the holder (40, 40A), the respective slide members (70, 70A) are parallel to the holder central axis from the molding position to the mold release position when the molded product (P, P2) is released. A guide (44) is provided that guides along the inclined direction that moves simultaneously in the relief direction from the undercut portions (P1, P3), which is the radial direction of the holder central axis, respectively. Undercut processing mechanism (30, 30A).

[2] In a molding die device (20) for molding a molded product (P) having an undercut portion (P1) by a fixed mold (11) and a movable mold (12), the molded product (P) is die-cut. In the undercut processing mechanism (30) in which the undercut part (P1) is sometimes removable,
An ejector pin (21) that is driven in a die-cutting direction to project and an end portion (23) of the ejector pin (21) is slidably guided and is disposed in the movable die (12). Holder (40), three or more slide members (70) accommodated radially in the holder (40) opposed to the center axis of the holder, and the mutually opposing portions of the tip of each slide member (70) An undercut molding part (80) provided in the
Each of the slide members (70) slides between a molding position where the tip portions thereof are in contact with each other in the holder (40) and a mold release position where the tip portions are separated from each other outside the holder (40). Each slide member (70) is stored in a holder (40) in a possible manner, and each of the slide members (70) has a base end portion that is in a radial direction of the holder central axis with respect to the tip end portion (23) of the ejector pin (21). It is slidably connected in the escape direction from the undercut part (P1),
As the ejector pin (21) protrudes into the holder (40) during die cutting, the slide members (70) are parallel to the holder central axis from the molding position to the mold release position. An undercut processing mechanism (30), characterized in that a guide (44) is provided that guides along an inclination direction that moves simultaneously in the die-cutting direction and the escape direction.

[3] In a molding die device (20A) for molding a molded product (P2) having an undercut portion (P3) with a fixed mold (11A) and a movable mold (12A), the molded product (P2) is demolded In the undercut processing mechanism (30A), which sometimes allows the undercut portion (P3) to be removed,
A holder (40A) disposed in the fixed mold (11A), a slide member (70A) in which three or more in the holder (40A) are radially accommodated facing the center axis of the holder, and each slide member An undercut molding part (80A) provided at a portion of the tip part of (70A) facing each other, and a holding member (51) accommodated in the holder (40A) so as to be slidable in parallel with the holder central axis. Have
Each of the slide members (70A) slides between a molding position where the tip portions thereof are in contact with each other within the holder (40A) and a mold release position where the tip portions are separated from each other outside the holder (40A). Each of the slide members (70A) is stored in a holder (40A) as possible, and each of the slide members (70A) has an undercut portion whose base end portion is in the radial direction of the holder central axis with respect to the distal end portion of the holding member (51). (P3) is slidably connected in the escape direction, the holding member (51) is urged in a direction to push the slide members (70A) from the molding position to the mold release position,
Each slide member (70A) is moved into the holder (40A) according to the movement of the holding member (51) in the urging direction as the movable die (12A) is separated from the fixed die (11A) during die cutting. A guide (44) is provided that guides along a tilting direction that simultaneously moves in the die-cutting direction parallel to the holder center axis and in the escape direction from the molding position to the mold release position. The undercut processing mechanism (30A).

  [4] An oblique groove (44) extending in the inclined direction is provided on one of the inner wall of the holder (40, 40A) and the outer wall of the slide member (70, 70A) that are in sliding contact with each other, Also, an oblique line (72) extending in the inclined direction and slidably fitted into the oblique groove (44) is provided, and the oblique groove (44) or oblique line (72) in the holder (40, 40A) is provided. ) As the guide (44), the undercut processing mechanism (30, 30A) according to [1], [2] or [3].

  [5] [1], [2], [3] or [4] characterized in that the undercut molding part (80, 80A) is integrally provided at the tip of the slide member (70, 70A). ] Undercut processing mechanism (30, 30A).

  [6] [1], [2], [3] or [3], wherein the undercut molded part (80, 80A) is detachably assembled as a separate body to the tip of the slide member (70, 70A) The undercut processing mechanism (30, 30A) according to [4].

  [7] The slide member (70, 70A) is set to a length corresponding to a punching stroke of the molded product (P, P2). [1], [2], [3], The undercut processing mechanism (30, 30A) according to [4], [5] or [6].

  [8] At least one of the undercut forming portions (80, 80A) is different from the others for each of the slide members (70, 70A), and undercut portions (P1, P3) having different shapes can be formed. The undercut processing mechanism (30, 30A) according to [1], [2], [3], [4], [5], [6] or [7], which is characterized in that there is.

  [9] The holder (40, 40A) itself is configured as the movable mold (12, 12A) or the fixed mold (11, 11A) in which the holder (40, 40A) is disposed. [1], [2], [3], [4], [5], [6], [7] or [8] The undercut processing mechanism (30, 30A).

The present invention operates as follows.
According to the undercut processing mechanism (30, 30A) described in [1], the slide member (70, 70A) provided with the undercut forming portion (80, 80A) is replaced with the ejector base plate (13) or the movable type. Without being dispersed in (12, 12A), it is possible to concentrate on only one of the fixed mold (11, 11A) and the movable mold (12, 12A) via the holder (40, 40A). it can. As a result, a compact configuration can be achieved and a space-saving request can be met, and processing and incorporation into a mold are facilitated.

  Three or more slide members (70, 70A) are accommodated radially in the holder (40, 40A) so as to oppose the central axis thereof. It is possible to slide between a molding position where the holders (40, 40A) are in contact with each other and a mold release position where the tips are separated from each other outside the holder (40, 40A). As a result, it is easy even for a molded product (P, P2) having a complicated shape in which there are a plurality of undercut portions (P1, P3) that are radially located around the entire circumference of the molded product (P, P2). It can correspond to.

  The undercut processing mechanism (30, 30A) is used for undercut portions (P1, P3) of the molded product (P, P2) when the molded product (P, P2) is removed by the molding die device (20, 20A). ) Operates so that it can be removed. That is, as the molded product (P, P2) is released from the mold, the slide members (70, 70A) are moved in the holder (40, 40A) by the guide (44) so that the direction of die release parallel to the center axis of the holder. Each of the guides is guided in an inclination direction that moves simultaneously in a clearance direction that is a radial direction of the holder central axis. As a result, each slide member (70, 70A) reliably moves from the molding position to the mold release position, so that the undercut portions (P1, P3) of the molded product (P, P2) can be removed, and the molded product. (P, P2) can be punched.

  As described above, the slide members (70, 70A) each having the undercut forming portion (80, 80A) can be punched along the guide (44) in the holder (40, 40A). Guided to move to. With this configuration, the overall structure can be simplified, and the manufacturing cost can be greatly reduced. When the molded product (P, P2) is removed, each slide member (70, 70A) returns from the mold release position to the initial molding position as the movable mold (12, 12A) returns to the molding position. . As a result, the next molded product (P, P2) is molded.

  According to the undercut processing mechanism (30) described in [2], the slide member (70) connected to the ejector pin (21) that is driven in the die-cutting direction and protrudes is the same as in [1]. In addition, it can be concentrated on the movable mold (12) via the holder (40). As a result, a compact configuration can be achieved and a space-saving request can be met, and processing and incorporation into a mold are facilitated. Similarly to the above [1], three or more slide members (70) are radially housed in the holder (40), and a plurality of slide members (70) are radially disposed over the entire circumferential direction of the molded product (P). It is possible to easily cope with a molded product (P) having a complicated shape having an undercut portion (P1).

  The undercut processing mechanism (30) operates in accordance with the ejecting operation of the ejector pin (21) driven in the die-cutting direction when the molded product (P) is die-cut by the molding die device (20). When molding is finished and the fixed mold (11) is separated from the movable mold (12), one side of the molded product (P) appears. Next, the ejector pin (21) is pushed out so as to separate the molded product (P) from the movable die (12) for die cutting, and the tip (23) of the ejector pin (21) is moved to the holder (40). ) Is slidably guided.

  At this time, in the holder (40), the slide member (70) connected to the tip end portion (23) of the ejector pin (21) is held by the guide (44) by the ejecting operation of the ejector pin (21). They are guided in an inclined direction that moves simultaneously in the die-cutting direction parallel to the central axis and the relief direction that is the radial direction of the holder central axis. As a result, each slide member (70) reliably moves from the molding position to the release position, so that the undercut portion (P1) of the molded product (P) can be removed, and the molded product (P) is removed. can do.

  Thus, the slide members (70) each having the undercut forming portion (80) are guided in the holder (40) in accordance with the ejecting operation of the ejector pins (21) driven in the mold release direction. 44) and is guided so as to move in the inclined direction in which the die can be removed. With this configuration, the overall structure can be simplified, and the manufacturing cost can be greatly reduced.

  According to the undercut processing mechanism (30A) described in [3], the slide member (70A) including the undercut forming portion (80A) is dispersed in the ejector base plate (13) and the movable mold (12A). Without being movable, the movable mold (12A), not the fixed mold (11A), can be arranged centrally via the holder (40A). As a result, a compact configuration can be achieved and a space-saving request can be met, and processing and incorporation into a mold are facilitated. Similarly to the above [1] and [2], three or more slide members (70A) are radially accommodated in the holder (40A), and are radially spread over the entire circumferential direction of the molded product (P2). It is possible to easily cope with a molded product (P2) having a complicated shape having a plurality of positioned undercut portions (P3).

  The undercut processing mechanism (30A) is configured so that the undercut portion (P3) of the molded product (P2) can be removed when the molded product (P2) is removed by the molding die device (20A). Operate. That is, as the movable die (12A) moves away from the fixed die (11A) during die cutting, each slide member is moved by the guide (44) in the holder (40A) as the holding member (51) moves in the biasing direction. (70A) is guided in an inclination direction that moves simultaneously in a die-cutting direction parallel to the holder central axis and an escape direction that is a radial direction of the holder central axis. As a result, each slide member (70A) reliably moves from the molding position to the release position, so that the undercut portion (P3) of the molded product (P2) can be removed, and the molded product (P2) is removed from the mold. can do.

  Thus, in the case where the slide members (70A) each having the undercut forming portion (80A) are provided on the fixed mold (11A), each slide member (70A) is movable when the mold is released (12A). Is moved along the guide (44) in the holder (40A) along with the urging force so as to move in the tilting direction in which the die can be removed. With this configuration, the overall structure can be simplified, and the manufacturing cost can be greatly reduced.

  According to the undercut processing mechanism (30, 30A) described in [4], the inclination is applied to any one of the inner wall of the holder (40, 40A) and the outer wall of the slide member (70, 70A) that are in sliding contact with each other. An oblique groove (44) extending in the direction is provided, and an oblique line (72) extending in the inclined direction and slidably fitted into the oblique groove (44) is provided on either one of the holders (40, 40A). The oblique groove (44) or the oblique line (72) in the parenthesis is used as the guide (44).

  Accordingly, the movement of each slide member (70, 70A) is caused by the fitting relationship between the slant groove (44) and the oblique line (72) provided in the slide member (70, 70A) itself and the holder (40, 40A). As a result, the durability is enhanced because the load during die cutting is dispersed without being concentrated in one place. In addition, since high accuracy at the time of design is eased, further cost reduction is possible.

  According to the undercut processing mechanism (30, 30A) described in [5] above, the undercut molding part (80, 80A) is provided integrally at the tip of the slide member (70, 70A), so that The structure becomes simple and the cost can be reduced.

  According to the undercut processing mechanism (30, 30A) described in [6] above, the undercut molding part (80, 80A) is detachably assembled to the tip of the slide member (70, 70A). , It becomes possible to replace with various undercut molded parts (80, 80A) later, and versatility is expanded.

  According to the undercut processing mechanism (30, 30A) described in [7] above, the slide member (70, 70A) is set to a length corresponding to the die-cutting stroke of the molded product (P, P2). Thus, it is possible to appropriately cope with a large stroke to a small stroke in the die cutting of the molded product (P, P2).

  According to the undercut processing mechanism (30, 30A) described in [8], at least one of the undercut forming portions (80, 80A) differs from the other for each slide member (70, 70A), Undercut portions (P1, P3) having different shapes can be formed. Thereby, for example, a plurality of undercut portions (P1, P3) that are radially located over the entire circumferential direction of the molded product (P, P2) can be easily handled even when the positions and shapes are different. It becomes possible to do.

  According to the undercut processing mechanism (30, 30A) described in [9], the holder (40, 40A) itself is movable type (12, 12A) or fixed type in which the holder (40, 40A) is disposed. (11, 11A). That is, a hollow portion serving as a substitute for the inner space of the holder (40, 40A) is directly formed in the mold (10, 10A), and each slide member (70, 70A) is placed in the hollow portion, and the molding position and the mold release. It only has to be slidably stored in the position. This eliminates the need for the holder (40, 40A), reduces the number of parts, further simplifies the overall configuration of the molding die device (20, 20A), and reduces costs. It becomes.

  According to the undercut processing mechanism according to the present invention, since each slide member is integrated in the holder, the slide member corresponding to the conventional slide core is not dispersed in the ejector base plate or the movable mold, It is possible to concentrate on only one of the fixed type and the movable type via the holder. As a result, a compact configuration can be achieved and a space-saving request can be met, and processing and incorporation into a mold are facilitated. Further, it is possible to eliminate the need for the angular pin and the loose core mechanism used in the conventional undercut punching method, and to reduce the mold manufacturing cost.

  Further, three or more slide members are accommodated radially in the holder so as to face the central axis thereof, and each slide member slides in a molding position and a release position, respectively, so that the entire circumferential direction of the molded product is achieved. It is also possible to easily form a molded product having a complicated shape having a plurality of undercut portions that are located radially. In particular, if at least one undercut molding part is different from the others for each slide member and can form undercut parts having different shapes, for example, the undercut molding parts are located radially over the entire circumferential direction of the molded product. Such a plurality of undercut portions can be easily handled even when the positions and shapes are different.

Hereinafter, various preferred embodiments of the present invention will be described with reference to the drawings.
1 to 5 show a first embodiment of the present invention.
FIG. 1 is a cross-sectional view for explaining the operation of the molding die apparatus 20 according to the first embodiment of the present invention. FIG. 2 is an explanatory view showing an undercut processing mechanism 30 incorporated in the molding die apparatus 20. FIG. 3 is an exploded perspective view showing an assembly process of the undercut processing mechanism 30.

  As shown in FIG. 1, the molding die apparatus 20 is an apparatus that molds a molded product P having an undercut portion P <b> 1 with the mold 10. The mold 10 includes a fixed mold 11 that mainly molds an appearance portion of the molded product P, and a movable mold 12 that molds an inner surface of the molded product P mainly. The molded product P according to the present embodiment is a bottomed tubular member that is closed on one side, and the undercut portion P1 is a tubular projection that projects in four directions from the outer periphery of the molded product P. The material of the molded product P includes not only a synthetic resin such as plastic but also a metal such as iron.

  The molding die apparatus 20 includes an undercut processing mechanism 30 that enables the undercut portion P1 to be released when the molded product P is removed. The undercut processing mechanism 30 is disposed in the movable mold 12 in such a manner that the ejector pin 21 that is driven in the up-and-down direction, which is the die-cutting direction, and projects and the tip 23 of the ejector pin 21 is slidably guided. Holder 40 provided, four slide members 70 radially accommodated in the holder 40 opposite to the central axis thereof, and undercut molding portions provided at mutually opposing portions of the end portions of the slide members 70 80.

  As shown in FIG. 2, each slide member 70 has a molding position (see FIG. 2A) in which the tip portions thereof are in contact with each other inside the holder 40, and the tip portions are mutually outside the holder 40. It is accommodated in the holder 40 so as to be slidable at a separating position (see FIG. 2B). In addition, a total of four ejector pins 21 are arranged corresponding to each slide member 70.

  As shown in FIG. 1, the ejector pin 21 is formed of a round bar member. The bottom surface of the base end portion 22 is fixed to the ejector base plate 13 via the base bracket 25 and the knock pin 26 so that the ejector pin 21 is erected on the ejector base plate 13. The tip portion 23 of the ejector pin 21 is slidably inserted into the movable mold 12 or the holder 40. The ejector pin 21 is driven in the vertical direction with the vertical movement of the ejector base plate 13.

  As shown in FIGS. 1 to 3, in the holder 40, the four slide members 70 can slide in the molding position (see FIG. 2A) and the release position (see FIG. 2B), respectively. It consists of a cylindrical member which has an internal space. The holder 40 is fixed in a state of being accommodated in the movable mold 12, and the movable mold 12 includes a cylindrical cross-section space whose upper end surface is open to accommodate the holder 40, and a lower end surface of the movable mold 12. A vertical hole through which the ejector pin 21 is inserted is formed.

  As shown in FIG. 2 (c), in the inner space of the holder 40, a cylindrical insert 41 for shaping the inside of the molded product P is arranged along the holder central axis. The four vertical hole portions 42 that are arranged at equal intervals in the four directions centered on the central axis) and that the tip portions 23 of the respective ejector pins 21 are inserted are communicated upward from the middle of the respective vertical hole portions 42, and the slides. Four guide hole portions 43 through which the member 70 is inserted are formed.

  On the inner wall surface of each vertical hole portion 42 and guide hole portion 43 in the holder 40, each slide member 70 is parallel to the holder central axis so that each slide member 70 is directed from the molding position to the mold release position when the molded product P is released. An oblique groove 44 that is a guide that guides along the inclined direction that moves simultaneously in the die-cutting direction and the escape direction from the undercut portion P1 that is the radial direction of the holder central axis is continuously recessed.

  On the other hand, on both side edges of the slide member 70 described below, oblique stripes 72 are slidably fitted into the oblique grooves 44. Here, the oblique groove 44 may be provided on either the holder 40 or the slide member 70, and the oblique line 72 is provided on either one of them. In short, it is only necessary that the slide member 70 is configured to be movable in the above-described inclination direction during the die cutting operation. In addition, the cross section of the guide hole part 43 opened to the upper end surface of the holder 40 has a shape that is guided so as to be movable in the tilt direction in a state where the slide member 70 penetrates and tilts.

  As shown in FIGS. 1 to 3, the slide member 70 is formed of the illustrated piece-shaped member, and intersects the die cutting direction (vertical direction in FIG. 1) with respect to the distal end portion 23 of the ejector pin 21. The base end portion is connected so as to be slidable in the escape direction from the undercut portion P1 (left and right direction in FIG. 1). The tip 23 of the ejector pin 21 is provided with a holding piece 23a that is slidably disposed in the holder 40 in the mold release direction. On the other hand, at the base end portion of the slide member 70, there is provided an escape operation piece portion 71 that is connected to the holding piece portion 23a so as to be slidable in the escape direction.

  As shown in FIG. 3, the holding piece 23 a is formed on the upper end surface of the distal end portion 23 of the ejector pin 21 as a ridge extending in the left-right direction perpendicular to the axial direction (vertical direction in FIG. 3) of the ejector pin 21. Is formed. On the other hand, the escape operation piece portion 71 of the slide member 70 is formed as a dovetail that fits movably to the left and right with respect to the protrusion of the holding piece portion 23a. The holding piece portion 23a and the escape operation piece portion 71 are connected to each other so as to be able to be pushed and pulled, and the slide member 70 is set to move in the inclined direction as the ejector pin 21 protrudes.

  Further, at both end edges of the inclined surface portions facing the outside of the slide member 70, the ridges 72 that are inclined and extend over the upper and lower ends and slidably fit into the oblique grooves 44 in the holder 40 are projected. It is installed. Here, the oblique line 72 is inclined in the same direction as the inclined groove 44, that is, at the same angle as the inclined direction in which the slide member 70 moves. As described above, the oblique line 72 may be protruded from the holder 40, while the inclined groove 44 may be recessed from the slide member 70.

  As shown in FIGS. 1 to 5, an undercut forming portion 80 for forming the undercut portion P <b> 1 of the molded product P is provided at a portion of the tip portion of each slide member 70 facing each other. The undercut molding portion 80 according to the present embodiment is detachably assembled as a separate member at the tip portion of the slide member 70, but the undercut molding portion 80 is integrally provided at the tip portion of the slide member 70. You may comprise.

Next, the operation of the first embodiment will be described.
According to the undercut processing mechanism 30 according to the present embodiment, the slide member 70 provided with the undercut forming portion 80 is not dispersed on the ejector base plate 13 or the movable die 12, and the movable die 12 is interposed via the holder 40. It can be concentrated and arranged only. As a result, a compact configuration can be achieved, a request for space saving can be met, and processing and incorporation into the mold 10 are facilitated.

  As shown in FIG. 2, the undercut processing mechanism 30 can be configured as a unit that is preliminarily incorporated in the holder 40, and can be easily retrofitted into the movable mold 12 via the holder 40 as shown in FIG. 1. can do. Such a configuration is suitable for a case where processing such as making a space for housing the holder 40 in the movable mold 12 itself is easy, as in the case where the movable mold 12 is small.

  Four slide members 70 are accommodated radially in the holder 40 so as to oppose the center axis of the holder, and each slide member 70 has a distal end portion in the holder 40 as shown in FIG. In FIG. 2 (b), the tip portions slide to the mold release positions where the tip portions are separated from each other outside the holder 40. Thereby, the molded product P with a complicated shape having a plurality of undercut portions P1 radially disposed over the entire circumferential direction of the molded product P can be easily molded.

  In the present embodiment, the four undercut portions P1 of the molded product P are all the same. However, the undercut molded portion 80 having a different shape may be used for each slide member 70, or the removal direction may be different. Is possible. For this reason, for example, even if the plurality of undercut portions P1 that are radially disposed over the entire circumferential direction of the molded product P are different in position and shape, they are simultaneously molded by one undercut processing mechanism 30. Can do. Furthermore, not only the undercut processing mechanism 30 but also the mold 10 can be easily downsized, and the cost of the entire apparatus can be greatly reduced.

  FIG. 1A shows a state where the molding of the molded product P is completed by the molding die device 20. After the molding is finished and the fixed mold 11 is separated from the movable mold 12, as shown in FIG. 1 (b), when the ejector base plate 13 is driven upward, each ejector pin erected on the ejector base plate 13 is provided. In order to release the mold 21, the molded product P is projected straight out in the mold release direction (upward) so as to be separated from the movable mold 12.

  As can be seen in FIG. 1B, each slide member 70 connected to the tip 23 of each ejector pin 21 in the holder 40 accommodated in the movable mold 12 is released together with the ejector pin 21. The ejector pin 21 and the slide member 70 are relatively displaced with respect to the tip 23 of the ejector pin 21 in the direction of escaping simultaneously with the sliding direction. .

  In the present embodiment, at the distal end portion 23 of the ejector pin 21, there is a convex holding piece portion 23 a slidably disposed in the mold release direction within the movable die 12, and at the proximal end portion of the slide member 70. Since there is a dovetail-shaped escape operation piece 71 that is slidably connected to the holding piece 23a in the escape direction, the distal end portion 23 of the ejector pin 21 and the proximal end portion of the slide member 70 are It can connect reliably so that it may displace relatively in the state which can be pushed and pulled mutually.

  With the ejecting operation of the ejector pin 21, the slide member 70 is guided by being slidably fitted in the oblique groove 44, which is a guide in the holder 40, and parallel to the center axis of the holder. And the escape direction, which is the radial direction of the holder central axis, simultaneously move in the tilt direction. As a result, each slide member 70 reliably moves from the molding position to the mold release position, so that the undercut portion P1 of the molded product P can be removed, and the molded product P can be punched.

  Here, the movement of each slide member 70 is reliably and smoothly guided by the fitting relationship between the ridge 72 of the slide member 70 and the oblique groove 44 as a guide in the holder 40. In addition, since the load at the time of die-cutting is dispersed without being concentrated in one place, durability is improved. In addition, since high accuracy at the time of design is eased, further cost reduction is possible.

  As described above, the slide members 70 each having the undercut forming portion 80 can be punched along the oblique grooves 44 in the holder 40 in accordance with the ejecting operation of the ejector pin 21 driven in the punching direction. Therefore, the entire structure can be simplified, and the manufacturing cost can be greatly reduced. When the molded product P is removed, as the ejector pin 21 returns to the molding position, the ejector pin 21 pulls the slide member 70 and the undercut molding portion 80 to the initial position. Further, the fixed mold 11 also returns to the molding position, and the next molded product P is molded.

  By the way, by setting the slide member 70 to a length corresponding to the punching stroke of the molded product P, it is possible to appropriately handle from a large stroke to a small stroke in the punching of the molded product P. Further, by nitriding the portion where the slide member 70 and the holder 40 are in sliding contact, particularly the surfaces of the oblique line 72 and the inclined groove 44, the friction coefficient can be reduced and the operation can be performed more smoothly. it can.

6 to 11 show a second embodiment of the present invention.
In the molding die apparatus 20A according to the present embodiment, the holder 40A constituting the undercut processing mechanism 30A is fixed in a state of being housed in the fixed mold 11A instead of the movable mold 12A in the mold 10A. The vertical posture is opposite to that of the first embodiment. The molded product P2 according to the present embodiment is a tubular member having both ends opened, and the undercut portion P3 is a tubular projection that projects in four directions from the outer periphery of the molded product P2. The material of the molded product P2 includes not only a synthetic resin such as plastic but also a metal such as iron.

  As shown in FIG. 6, the undercut processing mechanism 30A includes a holder 40A disposed in the fixed mold 11A, four slide members 70A that are radially accommodated in the holder 40A and opposed to the central axis thereof, An undercut molding portion 80A provided at a portion of each slide member 70A facing each other, and a holding member 51 accommodated in the holder 40A so as to be slidable in parallel with the center axis of the holder. Yes.

  As shown in FIG. 6, each slide member 70 </ b> A has a molding position (see FIG. 6A) in which the respective front end portions are in contact with each other in the holder 40 </ b> A, and the front end portions are mutually outside the holder 40 </ b> A. It is accommodated in the holder 40A so as to be slidable at a separating position (see FIG. 6C). Also, a total of four holding members 51 are arranged corresponding to each slide member 70A. In addition, the same code | symbol is attached | subjected to the site | part of the same kind as 1st Embodiment, and the overlapping description is abbreviate | omitted.

  As shown in FIGS. 6 to 9, in the holder 40A, the four slide members 70A and the holding member 51 have a molding position (see FIG. 6A) and a release position (see FIG. 6C), respectively. It consists of a cylindrical member which has an internal space which can slide. The holder 40A is fixed in a state of being accommodated in the fixed mold 11A. The fixed mold 11A has a cylindrical cross-sectional space opened on the lower end surface side to accommodate the holder 40A, and the upper end surface of the movable mold 12A. A vertical hole is formed through which the spring member 50 is inserted to urge the holding member 51 in the mold release direction (downward in the drawing).

  As shown in FIGS. 6 and 9, a cylindrical insert 41A for forming the inside of the molded product P2 along the center axis of the holder is arranged in the inner space of the holder 40A. The four vertical hole portions 42 (see FIG. 9) through which the holding members 51 are inserted are communicated downward from the middle of each vertical hole portion 42, and are arranged at equal intervals in four directions around the central axis). Four guide hole portions 43 (see FIG. 8) through which each slide member 70A is inserted are formed.

  In the vertical hole portion 42 and the guide hole portion 43 in the holder 40A, when the molded product P2 is punched, each slide member 70A is directed from the molding position to the mold release position, and a die-cutting direction parallel to the holder central axis, In addition, a slant groove 44 that is a guide that guides along the inclination direction that simultaneously moves in the escape direction from the undercut portion P3 that is the radial direction of the holder central axis is continuously recessed. On the other hand, on the slide member 70A described below, a ridge 72 is fitted so as to be slidably fitted in the oblique groove 44.

  As shown in FIGS. 8 to 11, the holding member 51 is formed of a short round bar member. The holding member 51 is accommodated in the vertical hole portion 42 in the holder 40A so as to be slidable within a predetermined range in parallel with the center axis of the holder. Further, the holding member 51 is biased by the spring member 50 partially inserted in the holding member 51 in the mold release direction (downward in FIG. 6), that is, the direction in which each slide member 70A is pushed from the molding position to the mold release position. Has been. In the present embodiment, the ejector pin 21 does not exist, and a holding piece portion 52 similar to the holding piece portion 23 a of the ejector pin 21 is provided at the distal end portion of the holding member 51.

  The slide member 70A is configured in substantially the same manner as the slide member 70 of the first embodiment, and is connected to the base end portion so as to be slidable in the escape direction with respect to the holding piece portion 52. An escape operation piece 71 is provided. Further, a taper groove 73 is provided on the end surface of the slide member 70A so that the engaging claw 60 provided on the movable mold 12A side engages while relatively escaping. The engagement claw 60 and the taper groove 73 are structures for ensuring the initial operation at the time of punching in combination with the urging force of the spring member 50. In addition, the undercut molding part 80A is assembled | attached to the site | part which mutually opposes the front-end | tip part of each slide member 70A so that attachment or detachment is possible.

Next, the operation of the second embodiment will be described.
According to the undercut processing mechanism 30A according to the present embodiment, the ejector base plate 13 is not necessary, and the slide member 70A including the undercut forming portion 80A is concentrated and disposed only on the fixed die 11A via the holder 40A. Can be set. As a result, a compact configuration can be achieved and a space-saving request can be met, and processing and incorporation into the mold 10A are facilitated.

  Similarly to the case of the first embodiment, the four slide members 70A are accommodated radially in the holder 40A, and a plurality of undercut portions P3 are located radially over the entire circumferential direction of the molded product P2. It is possible to easily cope with a molded product P2 having a complicated shape. In addition, since there is no interference between the ejecting operation of the ejector pin 21 and the slide member 70A, the projecting position of the slide member 70A can be arbitrarily set.

  The undercut processing mechanism 30A operates so that the undercut portion P3 of the molded product P2 can be removed when the molded product P2 is punched by the molding die apparatus 20A. That is, as shown in FIGS. 6A to 6C, when the movable die 12A starts to be separated from the fixed die 11A during die cutting, the taper groove 73 of each slide member 70A is moved from the engaging claw 60 in the movable die 12A. The holding member 51 moves in the urging direction due to the urging force of the spring member 50.

  Accordingly, in the holder 40A, each slide member 70A is guided by the slant groove 44 in an inclination direction that moves simultaneously in a die-cutting direction parallel to the holder central axis and a relief direction that is a radial direction of the holder central axis. The Accordingly, each slide member 70A reliably moves from the molding position to the mold release position, so that the undercut portion P3 of the molded product P2 can be removed, and the molded product P2 can be punched.

  As described above, in the case where each of the slide members 70A provided with the undercut molding portion 80A is provided in the fixed mold 11A, each slide member 70A is moved away from the fixed mold 11A when the mold is removed. Together with the urging force, it is guided along the inclined groove 44 in the holder 40A so as to move in the inclined direction in which the die can be removed. With this configuration, the overall structure can be simplified, and the manufacturing cost can be greatly reduced.

  Although the embodiments of the present invention have been described with reference to the drawings, the specific configuration is not limited to the above-described embodiments, and the present invention can be changed or added without departing from the scope of the present invention. Included in the invention. For example, the shapes of the molded products P and P2 and the undercut portions P1 and P3 are not limited to those illustrated.

  In each of the above embodiments, the outer peripheral shape of the holders 40, 40A is a cylindrical shape. However, for example, the holders 40, 40A may be designed as a rectangular column. In each of the above-described embodiments, four slide members 70 and 70A are provided. For example, three slide members 70 and 70A are provided radially, or five, six, and seven or more, depending on the arrangement space in the holder. An appropriate number can be provided.

  Moreover, in each said embodiment, although the undercut shaping | molding parts 80 and 80A in each slide member 70 and 70A are all the same shapes and comprise the extraction direction in the same direction, the undercut shaping | molding parts 80 and 80A are comprised, Each of the slide members 70 and 70A may be configured so that at least one of the slide members 70 and 70A is different from the other, and the undercut portions P1 and P2 having different shapes can be formed. For example, it is possible to make all the undercut molded parts 80 and 80A have different shapes and punching directions.

  In each of the above-described embodiments, the undercut molded portions 80 and 80A are detachably assembled as separate bodies at the distal ends of the slide members 70 and 70A, so that the various undercut molded portions 80 and 80A can be attached later. It can be changed and versatility is expanded. On the other hand, you may comprise so that the undercut shaping | molding part 80 may be integrally provided in the front-end | tip part of the slide member 70. FIG. Thereby, the structure is further simplified, and the cost can be reduced.

  In the first embodiment, the same number of ejector pins 21 as three or more slide members 70 are prepared corresponding to each slide member 70. However, as another configuration, for example, one ejector pin 21 is provided. Only the holding piece portion 23a (or the relief action piece portion corresponding to the escape action piece portion 71 (or the holding piece portion 23a) at the proximal end portion of each slide member 70 is provided at the distal end portion 23 of the ejector pin 21. 71) may be provided together. The same applies to the holding member 51 of the second embodiment.

  In each of the above-described embodiments, the guides for guiding the slide members 70 and 70A in the tilt direction are provided in the holders 40 and 40A by providing the oblique grooves 44 that fit into the oblique lines 72 of the slide members 70 and 70A. However, for example, a guide hole is formed in the end surface portion of the holder 40, 40A so that the slide member 70, 70A is movably guided in a tilted state. 40A may be provided with a groove for slidably guiding the entire outer periphery of the slide members 70, 70A.

  Further, the holders 40 and 40A themselves may be configured as the movable molds 12 and 12A or the fixed molds 11 and 11A in which the holders 40 and 40A are disposed. That is, a hollow portion serving as an alternative to the inner space of the holder 40, 40A is formed directly on the mold 10, 10A, and the slide members 70, 70A can be slid between the molding position and the release position in the hollow portion. You just have to store it. This eliminates the need for the holders 40 and 40A, reduces the number of parts, further simplifies the overall configuration of the molding die devices 20 and 20A, and reduces the cost.

  Furthermore, as another configuration example according to the undercut portion of the molded product, an undercut molding portion is provided at a portion facing the outside of the tip portion of each slide member 70, 70A, and each slide member 70, 70A is respectively In the holder 40, 40A (or in the gold) so as to be slidable between a molding position where the tip parts are separated from each other outside the holder 40, 40A and a mold release position where the tip parts are in contact with each other in the holder 40, 40A. The mold 10 itself may be housed.

It is sectional drawing explaining operation | movement ((a) at the time of shaping | molding, (b) after mold release) of the shaping die apparatus which concerns on the 1st Embodiment of this invention, and its undercut process mechanism. It is explanatory drawing which shows the undercut process mechanism which concerns on the 1st Embodiment of this invention. It is a disassembled perspective view which shows the undercut process mechanism which concerns on the 1st Embodiment of this invention. It is explanatory drawing which shows the ejector pin and slide member of the undercut process mechanism which concern on the 1st Embodiment of this invention. It is explanatory drawing which shows the ejector pin and slide member of the undercut process mechanism which concern on the 1st Embodiment of this invention. Sectional drawing explaining operation | movement ((a) At the time of shaping | molding, (b) In the middle of mold release, (c) After mold release) of the molding die apparatus concerning the 2nd Embodiment of this invention and its undercut process mechanism It is. It is explanatory drawing which shows the undercut process mechanism which concerns on the 2nd Embodiment of this invention. It is a disassembled perspective view which shows the undercut process mechanism which concerns on the 2nd Embodiment of this invention. It is a disassembled perspective view which shows the undercut process mechanism which concerns on the 2nd Embodiment of this invention. It is explanatory drawing which shows the ejector pin and slide member of the undercut process mechanism which concern on the 2nd Embodiment of this invention. It is explanatory drawing which shows the ejector pin and slide member of the undercut process mechanism which concern on the 2nd Embodiment of this invention.

Explanation of symbols

P ... Molded product P1 ... Undercut part P2 ... Molded product P3 ... Undercut part 10 ... Mold 10A ... Mold 11 ... Fixed mold 11A ... Fixed mold 12 ... Movable mold 12A ... Movable mold 13 ... Ejector base plate 20 ... Molded Mold device 20A ... Mold device 21 ... Ejector pin 23 ... Tip 23a ... Holding piece 30 ... Undercut mechanism 30A ... Undercut mechanism 40 ... Holder 40A ... Holder 41 ... Nest 41A ... Nest 42 ... Vertical hole 43 ... Guide hole 44 ... Slanted groove 50 ... Spring member 51 ... Holding member 52 ... Holding piece 60 ... Engagement claw 70 ... Sliding member 70A ... Sliding member 71 ... Escape action piece 72 ... Slanted ridge 73 ... Tapered groove 80 ... Undercut molding part 80A ... Undercut molding part

Claims (9)

In a mold apparatus for molding a molded product having an undercut portion with a fixed mold and a movable mold, in an undercut processing mechanism that allows the undercut portion to be removed when the molded product is die-cut,
A holder disposed in the fixed mold or the movable mold, a slide member in which three or more are housed radially in the holder and opposed to the center axis of the holder, and a portion of each slide member facing each other An undercut molding part provided in the
Each of the slide members is housed in the holder so as to be slidable at a molding position where the respective front end portions come into contact with each other in the holder and a release position where the front end portions are separated from each other outside the holder,
In the holder, when the molded product is die cut, the slide members are directed from the molding position to the mold release position, the die cutting direction parallel to the holder central axis, and the under direction being the radial direction of the holder central axis. An undercut processing mechanism, characterized in that a guide is provided for guiding along an inclination direction that simultaneously moves in the escape direction from the cut portion. In a mold apparatus for molding a molded product having an undercut portion with a fixed mold and a movable mold, in an undercut processing mechanism that allows the undercut portion to be removed when the molded product is die-cut,
An ejector pin that is driven in the die-cutting direction and protrudes, a holder that is disposed in the movable mold in a state where the tip of the ejector pin is slidably guided, and three or more holders in the holder A slide member radially accommodated facing the central axis, and an undercut molding portion provided at a portion facing each other at the tip of each slide member,
Each slide member is housed in the holder so as to be slidable at a molding position where the respective front end portions come into contact with each other within the holder and a release position where the front end portions are separated from each other outside the holder, Each slide member is slidably connected in the escape direction from the undercut portion, which is the radial direction of the holder central axis, with respect to the distal end portion of the ejector pin.
In the holder, with the ejecting operation of the ejector pin at the time of die-cutting, the slide members are moved from the molding position to the mold-release position, in a die-cutting direction parallel to the holder central axis, and in the escape direction. An undercut processing mechanism, characterized in that a guide is provided for guiding along an inclined direction that moves simultaneously. In a mold apparatus for molding a molded product having an undercut portion with a fixed mold and a movable mold, in an undercut processing mechanism that allows the undercut portion to be removed when the molded product is die-cut,
A holder disposed in the fixed mold, three or more slide members accommodated radially in the holder opposed to the central axis of the holder, and provided at portions of the tip portions of the slide members facing each other. An undercut molding part, and a holding member that is slidably housed in parallel with the holder central axis in the holder,
Each slide member is housed in the holder so as to be slidable at a molding position where the respective front end portions come into contact with each other within the holder and a release position where the front end portions are separated from each other outside the holder, Each slide member is connected to the distal end portion of the holding member so that the base end portion is slidable in the escape direction from the undercut portion, which is the radial direction of the holder central axis. Each slide member is biased in the direction of pushing out from the molding position to the release position,
As the movable mold moves away from the fixed mold during die cutting, the slide members are moved from the molding position toward the mold release position in accordance with the movement of the holding member in the biasing direction. An undercut processing mechanism, characterized in that a guide is provided for guiding along an inclination direction that moves simultaneously in a die-cutting direction parallel to the shaft and in the escape direction.   Either one of the inner wall of the holder and the outer wall of the slide member that are in sliding contact with each other is provided with an oblique groove extending in the inclined direction, and the other is also extended in the inclined direction and slidable in the oblique groove. The undercut processing mechanism according to claim 1, wherein an oblique line to be fitted is provided, and an oblique groove or an oblique line in the holder is used as the guide.   The undercut processing mechanism according to claim 1, 2, 3, or 4, wherein the undercut forming portion is integrally provided at a tip portion of the slide member.   5. The undercut processing mechanism according to claim 1, wherein the undercut forming portion is removably assembled to a distal end portion of the slide member as a separate body.   The undercut processing mechanism according to claim 1, 2, 3, 4, 5 or 6, wherein the slide member is set to a length corresponding to a die cutting stroke of the molded product.   The at least one undercut forming portion is different from the others for each slide member, and undercut portions having different shapes can be formed. The undercut processing mechanism according to 6 or 7.   The undercut processing mechanism according to claim 1, 2, 3, 4, 5, 6, 7 or 8, wherein the holder itself is configured as the movable mold or the fixed mold in which the holder is disposed. .

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