JP2017177447A - Undercut processing mechanism and molding die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an undercut processing mechanism and a molding die capable of surely preventing breakage of a molded object during mold removal.SOLUTION: There is provided an undercut processing mechanism capable of molding an undercut part P1, comprising: a molding piece 20 formed of two or more division pieces for molding an outer peripheral face of the undercut part P1: a holding piece 30 which slidably engages to the molding piece 20, and opens and closes the molding piece 20; and a holder 40 which can advance and retreat for storing the holding piece 30 in a state of capable of advancing and retreating. The holding piece 30 can advance and retreat in the holder 40 in a state in which the holder 40 is resting. The molding piece 20 and holding piece 30 have an inclination surface, and engage each other slidably, through engagement means which are provided on the respective inclination surfaces. The holder 40 has a molding piece guide for guiding the molding piece 20 toward a mold removal direction of the undercut part P1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an undercut processing mechanism and a molding die that are capable of molding an undercut part and are used in a molding die that molds a molded product with a fixed die and a movable die.

  In a molding die for molding a molded product having an undercut with a fixed mold and a movable mold, many undercut processing mechanisms have been developed corresponding to the form of the undercut portion. For example, Patent Document 1 describes an undercut processing device capable of forming a formed product having an undercut portion on the outer periphery of a discharge portion.

  In the undercut processing device described in Patent Document 1, a cylindrical inner mold is provided at the tip of the holder, an open / close fixing pin is disposed at the center of the holder, and an undercut portion is provided outside the cylindrical inner mold. An outer part split mold provided with a cavity to be molded is arranged, and a taper part is provided on the opening / closing fixing pin and the holder housing part. This undercut processing device uses the taper portion to open the outer portion split mold in a radial manner as the mold is opened, and removes the undercut portion.

  In Patent Document 2, if the undercut portion is die-cut in a state where the entire molded product is not supported, not only the die-cutting efficiency of the molded product is good, but the molded product may be damaged due to excessive drawing. There is an undercut molding core, a holder incorporated in a fixed mold or a movable mold, and a slider that moves in the mold release direction within the holder, and the slider is moved in the mold release direction before opening the mold. Thus, an undercut processing mechanism is described in which only the undercut portion can be removed without releasing the mold.

Japanese Unexamined Patent Publication No. 7-47575 JP, 2014-226806, A

  The undercut processing apparatus described in Patent Literature 1 can form a formed product having an undercut portion on the outer periphery of the discharge portion, but has a large number of parts and a complicated structure. Further, since the undercut portion is punched in a state where the entire molded product is not supported, the molded product may be damaged by excessive drawing as pointed out in Patent Document 2.

  Since the undercut processing mechanism described in Patent Document 2 has a small number of parts and can remove only the undercut portion in a state where the mold is not released, damage to the molded product can be reliably prevented. Patent Document 2 describes an undercut processing mechanism for forming an undercut portion of a tubular boss and a horizontal hole. However, in the undercut processing mechanism described here, structurally, on the outer periphery of the discharge portion. Molded products with undercuts cannot be molded.

  An object of the present invention is to provide an undercut processing mechanism and a molding die that can reliably prevent damage to a molded product during die cutting.

  The present invention is an undercut processing mechanism capable of forming an undercut portion, which is attached to a molding die having a fixed mold and a movable mold for molding a molded product having an undercut section, A molding piece composed of two or more divided pieces for forming the outer peripheral surface of the metal, a holding piece that slidably engages with the shaping piece and opens and closes the shaping piece, and advancing and retreating that accommodates the holding piece in a reciprocating manner A holder, and the holding piece can move back and forth in the holder in a state where the holder is stationary, and the molding piece and the holding piece both have an inclined surface, and are provided on the inclined surface. The holder has a forming piece guide for guiding the forming piece in a die-cutting direction of the undercut portion, and the holding piece has the holding piece. Fits completely in the holder When the divided pieces come into contact with each other, the outer peripheral surface of the undercut portion is formed, and when the holding piece is retracted, the divided pieces move along the forming piece guide so that they are separated from each other, and the holder The undercut processing mechanism is characterized in that the molding piece is stationary in a state where the molded product is supported until it is removed from the undercut portion.

  Since this undercut processing mechanism can perform die cutting of the undercut portion with the holder supporting the molded product, it is possible to reliably prevent the molded product from being damaged during die cutting. Furthermore, since this undercut processing mechanism moves in the die-cutting direction of the undercut portion so that the divided pieces constituting the molding piece are separated from each other at the time of die-cutting, such as a protrusion formed on the outer peripheral surface of the protruding portion. It can also handle complex undercut parts.

  The undercut processing mechanism of the present invention further includes drive means for moving the holding piece and the holder back and forth, and the drive means can move the holding piece back and forth within the holder while the holder is stationary. It is characterized by that.

  The undercut processing mechanism of the present invention further includes an angular pin attached to the fixed mold or the movable mold, and the angular pin is disposed obliquely with respect to the moving direction of the movable mold, and the angular pin is The holding piece and the holder can be moved back and forth in a direction different from the moving direction of the movable type in conjunction with the reciprocating movement of the movable type.

  According to the present invention, the holding piece and the holder can be moved back and forth using the movable reciprocating movement as a drive source by the action of the angular pin, so that it is energy-saving and can be manufactured inexpensively and compactly.

  The undercut processing mechanism of the present invention further includes a stopper that stops the holder when the holding piece is retracted in the holder.

  According to the present invention, since the stopper can reliably prevent the holder from moving when the holding piece is retracted in the holder, the molded product can be more reliably prevented from being damaged during die cutting. .

  In the undercut processing mechanism of the present invention, each of the two or more divided pieces has a cavity for forming the outer peripheral surface of the undercut portion on the inner surface, the inclined surface on the outer surface, and the holding piece is 2 It has the said inclined surface, It is formed so that the inclination direction of each said inclined surface may correspond with the inclination direction of the said inclined surface of the said divided piece which mutually slides.

  According to the present invention, since the inclined direction of the inclined surface of the holding piece and the inclined surface of the sliding divided piece coincide with each other, the holding piece and the divided piece can be smoothly slid.

  Moreover, in the undercut processing mechanism of the present invention, the molded product having the undercut portion is a molded product having a protruding portion that protrudes in a direction different from the moving direction of the movable mold from the molded product body, and the undercut portion. Is a protrusion formed on the outer peripheral surface of the protrusion, and the protrusion is orthogonal to or inclined with respect to the molded product body, and the holder holds the holding piece at the same angle as the protrusion. A holding piece guide for guiding is provided, and the holding piece moves along the holding piece guide.

  Further, in the undercut processing mechanism of the present invention, the molded product having the undercut portion is a molded product having a tubular projecting portion projecting from a molded product body in a direction different from the moving direction of the movable mold, The cut portion is a protruding portion formed on the outer peripheral surface of the protruding portion, and a core pin for forming the inner peripheral surface of the protruding portion is attached to the holding piece.

  According to the present invention, the undercut portion is a protruding portion formed on the outer peripheral surface of the protruding portion protruding in a direction different from the moving direction of the movable mold from the molded product body, and the protruding portion is further formed on the molded product body. Intricate undercut portions that are inclined with respect to each other and whose projecting portions are annular are also very useful because they can be molded and punched out.

  Moreover, in the undercut processing mechanism of the present invention, the molded product having the undercut portion is a molded product having one or more ribs that are formed by projecting from the same plane as the projecting portions, and the ribs are to be molded. And one or more cavities formed in one or more members that move in the same direction as the protruding direction of the ribs.

  According to this invention, it is also possible to shape | mold the molded article which has a rib with the protrusion part which has an undercut part.

  The present invention also provides a molding die comprising a fixed die, a movable die, and the undercut processing mechanism.

  Since the under-molding part can be punched in a state where the fixed mold and the movable mold are closed, the present molding die can reliably prevent the molded product from being damaged during the punching.

  ADVANTAGE OF THE INVENTION According to this invention, the undercut process mechanism and the metal mold | die for shaping | molding which can prevent reliably the damage of the molded article at the time of die cutting can be provided.

It is a cross-sectional perspective view which shows the state at the time of shaping | molding of the shaping die apparatus 1 of 1st Embodiment of this invention. It is a cross-sectional view which shows the state at the time of shaping | molding of the shaping die apparatus 1 of FIG. It is a cross-sectional perspective view which shows the state in the middle of mold release of the undercut processing mechanism 13 of FIG. It is a cross-sectional view which shows the state in the middle of mold release of the undercut processing mechanism 13 of FIG. It is a cross-sectional perspective view which shows the state after mold release of the undercut process mechanism 13 of FIG. It is a cross-sectional view which shows the state after mold release of the undercut processing mechanism 13 of FIG. 2 is a perspective view of a molding piece 20, a holding piece 30, and a first holder 40 of the undercut processing mechanism 13 of FIG. It is a perspective view of the guide block 60, the stopper 70, and the slider 80 of the undercut processing mechanism 13 of FIG. It is a disassembled block diagram of the undercut processing mechanism 13 of FIG. It is a disassembled block diagram of the undercut processing mechanism 13 of FIG. It is a cross-sectional perspective view which shows the state at the time of shaping | molding of the shaping die apparatus 2 of 2nd Embodiment of this invention. It is a cross-sectional perspective view which shows the state in the middle of mold release of the molding die apparatus 2 of FIG. It is a cross-sectional perspective view which shows the state after mold release of the molding die apparatus 2 of FIG. It is a figure which shows an example of the molded product which can be shape | molded with the undercut process mechanism and molding die of this invention. It is a figure which shows an example of the molded product which can be shape | molded with the undercut process mechanism and molding die of this invention.

  FIG. 1 is a cross-sectional perspective view showing a state during molding of the molding die apparatus 1 according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view showing a state during molding of the undercut processing mechanism 13 of FIG. FIG. 3 is a cross-sectional perspective view showing a state in the middle of mold release of the undercut processing mechanism 13 of FIG. FIG. 4 is a cross-sectional view showing a state in the middle of mold release of the undercut processing mechanism 13 of FIG. FIG. 5 is a cross-sectional perspective view showing a state after the release of the undercut processing mechanism 13 of FIG. FIG. 6 is a cross-sectional view showing a state after the release of the undercut processing mechanism 13 of FIG. In FIG. 1, FIG. 3, and FIG. 5, some symbols are omitted.

  FIG. 7A is a perspective view of the forming piece 20, the holding piece 30, and the first holder 40 of the undercut processing mechanism 13 of FIG. FIG. 7B is a perspective view showing a state in which the molding piece 20 and the holding piece 30 are accommodated in the first holder 40. FIG. 8A is a perspective view of the guide block 60, the stopper 70, and the slider 80 of the undercut processing mechanism 13 of FIG. FIG. 8B is a perspective view illustrating a state in which the stopper 70 and the slider 80 are accommodated in the guide block 60. 9 and 10 are exploded structural views of the undercut processing mechanism 13 of FIG. In FIGS. 9 and 10, some of the reference numerals are omitted.

  The molding die apparatus 1 according to the first embodiment of the present invention is an apparatus that molds a molded product P having an undercut portion P <b> 1 with a molding die 10. The molded product P has a tubular projecting portion P2 that obliquely projects from one surface of a flat molded product body P3, and the undercut portion P1 is a projecting portion formed on the outer peripheral surface of the projecting portion P2.

  Here, the opening / closing direction (vertical direction in FIG. 1) of the molding die 10 is the Y direction, the direction orthogonal to the Y direction in the front view is the X direction, and the direction orthogonal to the Y direction in the side view is Z Direction (see FIG. 1). In addition, the Y direction is appropriately set as the upper and lower sides, and a description will be given assuming that the molded product P side in the X direction in the undercut processing mechanism 13 described later is the front and the opposite side is the rear.

  In the molded product P, the plane of the molded product main body P3 is molded in parallel to the Z direction. The protruding portion P2 is orthogonal to the Y direction and protrudes obliquely with respect to the X direction (and Z direction), and the undercut portion P1 protrudes from the outer periphery of the protruding portion P2 in the Z direction. For this reason, when the molding die 10 is released, before the molded product body P3 (molded product P) is punched, the undercut portion P1 must first be punched, and then the protruding portion P2 must be punched. There is.

  The molded product P is not limited to a specific shape. For example, the molded product main body P3 may have a box-like shape instead of a flat plate shape, and the protrusion P2 may be in the X direction (in the molded product main body P3). It may also protrude (perpendicular to). The material of the molded product P is not limited to a synthetic resin such as plastic, and may be a metal such as iron or copper, for example.

  The molding die 10 molds a fixed mold 11 positioned below the molded product P, a movable mold 12 positioned above the molded product P and movable up and down, and an undercut portion P1 (projecting portion P2). And an undercut processing mechanism 13.

  The undercut processing mechanism 13 includes a molding piece 20 that molds the outer peripheral surface of the undercut portion P1 (projecting portion P2) of the molded product P, and a holding piece that slidably engages with the molding piece 20 and opens and closes the molding piece 20. 30, a first holder 40 that accommodates the holding piece 30 so as to be able to advance and retreat, a second holder 50 that accommodates the first holder 40 and is a driving means for moving the holding piece 30 and the first holder 40 forward and backward, and the first holder 40. And a guide block 60 that guides the second holder 50, a stopper 70 that is accommodated in the guide block 60 so as to be movable up and down, and stops the first holder 40 during the movement of the holding piece 30, and slidably engaged with the stopper 70 A slider 80 for moving the stopper 70 up and down, a spring 90 for applying a forward force to the first holder 40, and a spring guide for guiding the spring 90 A connecting plate 110 that connects the second holder 50, the slider 80, and the spring guide pin 100, and a slide block 120 that is connected to the second holder 50 and moves back and forth in the X direction in conjunction with the vertical movement of the movable mold 12. The slide rail 130 for guiding the slide block 120 and the angular pin 140 for moving the slide block 120 forward and backward by the movement of the movable mold 12.

  In the undercut processing mechanism 13, the guide block 60 and the slide rail 130 are fixed to the fixed mold 11, the angular pin 140 is fixed to the movable mold 12, and the slide block 120 fixes the angular pin 140. In conjunction with the vertical movement of the movable mold 12, it advances and retreats in the X direction along the slide rail 130. When the slide block 120 advances and retreats, the second holder 50 connected to the slide block 120 is guided by the guide block 60 and moves forward and backward, and the second holder 50 is interposed via the holding piece 30, the first holder 40, and the connecting plate 110. The slider 80 and the spring guide pin 100 connected to each other advance and retreat, the molding piece 20 opens and closes in conjunction with this movement, and the stopper 70 moves up and down. Details of the operation of the undercut processing mechanism 13 will be described later.

  The molding piece 20 includes a pair of division pieces 21 and 22 that can be divided with the central axis of the projection P2 of the molded product P as a boundary, and molds the outer peripheral surface of the undercut portion P1 (projection P2) of the molded product P. . The molding piece 20 is slidably engaged with the holding piece 30 and opens and closes in the Z direction, which is the die cutting direction (protruding direction) of the undercut portion P1 in conjunction with the advance and retreat of the holding piece 30.

  The pair of divided pieces 21 and 22 are slidably fitted to an inclined surface 23 inclined at the same angle as one inclined surface 32 of a holding piece 30 described later, and a forming piece guide 47 of a first holder 40 described later. 7 is a block member in which a convex portion 24 to be joined, a cavity 25 for molding the outer peripheral surface of the undercut portion P1 (projecting portion P2), and a guide groove 26 serving as a passage path for a core pin 34 to be described later are formed. (See (a)).

  The pair of divided pieces 21 and 22 can be accommodated in a notch 31 of a holding piece 30 described later without a gap so that the inner surfaces of the divided pieces 21 and 22 come into contact with each other when the molding die 10 is closed. (See FIG. 7B).

  The inclined surfaces 23 of the pair of divided pieces 21, 22 are formed so that their inclination directions are opposite to each other so as to slide along one inclined surface 32 of the holding piece 30. Also, on the inclined surface 23 of the divided pieces 21 and 22, dovetail grooves 27 are formed as engaging means that slidably engage with protrusions 37 of a holding piece 30 described later.

  The convex portions 24 of the pair of split pieces 21 and 22 are formed on the lower surface in parallel to the Z direction so as to be slidable by fitting with the forming piece guide 47 of the first holder 40. When the holding piece 30 advances and retreats, the forming piece 20 slides with the inclined surface 23 along the inclined surface 32 of the holding piece 30, and the convex portion 24 is guided by the forming piece guide 47 of the first holder 40 and slides. This opens and closes in the Z direction (see FIGS. 2 and 4).

  The cavities 25 of the pair of split pieces 21 and 22 are formed on the side surfaces on the opposite side of the inclined surface 23 so that the projecting portion P2 of the molded product P can be formed when the two split pieces 21 and 22 come into contact with each other. Has been.

  The guide grooves 26 of the pair of divided pieces 21 and 22 protrude from the center of the rear end on the side surface where the cavity 25 is formed, respectively, so that the core pin 34 can pass when the two divided pieces 21 and 22 come into contact with each other. A semicircular groove cross-sectional shape is formed so as to communicate with the cavity 25 in the central axis direction of the portion P2.

  The pair of split pieces 21 and 22 are slidable along the inclined surfaces 23 and 32 by engaging the dovetail grooves 27 with the protrusions 37 of the holding pieces 30 so that the side surfaces on which the cavities 25 are formed face each other. Is attached to the holding piece 30. The divided pieces 21 and 22 are accommodated in the first holder 40 together with the holding pieces 30 so that the convex portions 24 are fitted into the forming piece guides 47 of the first holder 40 and are slidable along the forming piece guides 47. Yes.

  The holding piece 30 is slidably engaged with the forming piece 20, and opens and closes the forming piece 20 by moving back and forth in the first holder 40 in the direction of the central axis of the protruding portion P <b> 2 of the formed product P.

  The holding piece 30 is a block member having a cutout portion 31 cut out at the center of the front end portion so as to accommodate the molding piece 20 without a gap, and the two inclined surfaces 32 arranged in an inverted V shape are formed in the cutout portion 31. Have. On the upper surface of the holding piece 30, a convex portion 35 is formed in the width direction so as to be slidably fitted to and latched with a holding groove concave groove 51 of the second holder 50 described later. Further, a groove 36 into which the tip of the spring guide pin 100 is fitted is formed on the rear end surface of the holding piece 30, and the core pin 34 that forms the inner peripheral surface of the protruding portion P <b> 2 of the molded product P is notched from the bottom surface of the groove 36. It penetrates and is attached to the part 31 (refer FIG. 7).

  The inclined surface 32 of the holding piece 30 is formed with a ridge 37 that is an engaging means with the forming piece 20, and the dovetail 27 and the dovetail groove 27 formed on the inclined surface 23 of the forming piece 20 are interposed therebetween. The holding piece 30 and the forming piece 20 are slidably engaged along the inclined surfaces 23 and 32. The engaging means between the holding piece 30 and the forming piece 20 is not limited to the one using the protrusion 37 and the dovetail groove 27, and for example, a linear guide or the like can be used.

  The inclination angle of the inclined surface 32 of the holding piece 30 can be appropriately set to an optimum angle in consideration of the space where the undercut processing mechanism 13 is disposed. Increasing the inclination angle of the inclined surface 32 of the holding piece 30 with respect to the central axis of the protrusion P2 of the molded product P can reduce the stroke required to open and close the forming piece 20, but the width of the holding piece 30 is reduced. It becomes relatively large.

  The convex portion 35 is slidably fitted to and latched with a concave groove 51 for a holding piece, which will be described later, so that the holding piece 30 advances and retreats in conjunction with the advance and retreat of the second holder 50. In addition, the latching means of the holding | maintenance piece 30 and the 2nd holder 50 is not limited to this, For example, you may use a linear guide etc.

  The groove 36 is formed in a rectangular shape whose both ends are slidable in the Z direction so that the bottom surface and the tip surface of the spring guide pin 100 can slide in the Z direction when the holding piece 30 moves.

  The core pin 34 is a member of an elongated cylindrical body whose base end portion is expanded in diameter, and the base end portion whose diameter is expanded is used as a retaining member so that the center axis coincides with the center axis of the projecting portion P2 of the molded product P. The holding piece 30 is attached through the bottom surface of the groove 36 through the notch 31. The core pin 34 is not limited to a cylindrical body, and can be appropriately changed according to the cross-sectional shape of the inner peripheral surface of the protrusion P2 of the molded product P.

  The first holder 40 accommodates the holding piece 30 so as to be able to advance and retreat, guides the holding piece 30 at the same angle as the protrusion P2 of the molded product P, and guides the forming piece 20 in the Z direction. The first holder 40 is accommodated in the second holder 50 so as to be able to advance and retreat.

  The first holder 40 includes a holding piece guide 41 that accommodates and guides the holding piece 30 so as to be able to advance and retreat, a convex portion 42 that is hooked in a holder concave groove 52 of a second holder 50 described later, and a guide block 60 described later. A protrusion 43 slidably engaged with the dovetail groove, a round groove 45 that accommodates the spring 90, an insertion hole 44 through which the spring guide pin 100 is inserted, and a concave groove 46 into which the stopper 70 is fitted are formed. It is a block member (see FIG. 7).

  The holding piece guide 41 is formed in a groove cross-sectional shape by hollowing out the front end surface and the upper surface, and the holding piece 30 is slidable so that it can move forward and backward at the same angle as the protruding portion P2 of the molded product P. Is formed in parallel to the central axis of the protrusion P2 of the molded product P. Further, on the bottom surface of the holding piece guide 41, a forming piece guide 47 having a groove cross-sectional shape for guiding the forming piece 20 is formed in parallel to the Z direction.

  For example, dovetail grooves or protrusions may be formed on both side surfaces and the bottom surface of the holding piece guide 41, and a linear guide or the like may be provided. In short, the holding piece 30 can be guided in the direction of the central axis of the protruding portion P2 of the molded product P from the molding position shown in FIGS. 1 and 2 to the mold release position shown in FIGS. Any configuration may be used. Note that the holding piece 30 guided by the holding piece guide 41 may have an optimum configuration as appropriate according to the configuration of the holding piece guide 41.

  The forming piece guide 47 is formed on the bottom surface of the holding piece guide 41 over the entire width so as to be slidably fitted to the convex portion 24 of the forming piece 20 and guide the forming piece 20 in the Z direction. The molding piece guide 47 does not necessarily have to be formed over the entire width, and the molding piece 20 extends from the position at the time of molding shown in FIGS. 1 and 2 to the position at the time of release shown in FIGS. 5 and 6. It is only necessary that guidance in the Z direction is possible.

  Further, the forming piece guide 47 is not limited to a groove having a cross-sectional shape, and may be, for example, a convex portion, a dovetail groove, a ridge, or the like, or a linear guide or the like provided on the bottom surface of the holding piece guide 41. Good. In short, any configuration may be used as long as the molding piece 20 can be guided in the Z direction that is the die cutting direction of the undercut portion P1. Note that the molding piece 20 guided by the molding piece guide 47 may have an optimum configuration as appropriate according to the configuration of the molding piece guide 47.

  The convex portion 42 is formed so as to protrude from the rear end portions of both outer wall surfaces parallel to the X direction of the first holder 40. The formation range of the convex portion 42 is determined such that the convex portion 42 is latched in the holder concave groove 52 of the second holder 50 after the molding piece 20 is detached from the undercut portion P1 at the time of mold release.

  The protrusion 43 is formed in the center of the lower surface of the first holder 40 in parallel with the X direction, and slidably engages with a first dovetail groove 61 of a guide block 60 described later. The protrusion 43 is formed so that a step is generated between the front end face of the protrusion 43 and the front end face of the first holder 40, and the front end face of the protrusion 43 when the first holder 40 moves forward to the molding position. Is brought into contact with a convex portion 65 of a guide block 60 to be described later and latched. As in the case of the protrusion 37 of the holding piece 30 and the dovetail 27 of the forming piece 20, a linear guide or the like can be used instead of the protrusion 43 and the first dovetail 61, for example.

  The round groove 45 is formed in the center of the rear end surface of the first holder 40 so that the spring 90 can be inserted, and the bottom surface serves as a pressure receiving surface of the spring 90. The insertion hole 44 is pierced in the X direction from the bottom surface of the round groove 45 to the holding piece guide 41 in such a size that the spring guide pin 100 is not inserted and the spring 90 is not inserted.

  The concave groove 46 is formed in a shape that allows the stopper 70 to be fitted to the bottom surface of the first holder 40 without a gap. The formation position of the concave groove 46 is determined so that the concave groove 46 and the stopper guide 64 communicate with each other when the first holder 40 advances to the molding position and coincides with a formation position of a stopper guide 64 of the guide block 60 described later. It has been.

  The second holder 50 is a box-like member having an open bottom surface and a front end surface. The second holder 50 is slidably engaged with the guide block 60 in a state in which the first holder 40 is accommodated, and the holding piece 30 and the first holder 40 are connected. It functions as a driving means for advancing and retreating.

  The second holder 50 includes a holding piece concave groove 51 that latches on the convex portion 35 of the holding piece 30, a holder concave groove 52 that latches on the convex portion 42 of the first holder 40, and a guide block 60 described later. A protrusion 53 slidably engaged with the second dovetail groove 62, an insertion hole 54 for inserting the spring guide pin 100, a round groove 55 for accommodating the spring 90, and a mounting hole for attaching to the connecting plate 110. 56 and a mounting hole 57 for mounting the slide block 120 are formed (see FIG. 9).

  The holding piece concave groove 51 is fitted in the second holder 50 so that the convex portion 35 of the holding piece 30 is fitted and hooked at a position where the front end face of the second holder 50 and the front end face of the holding piece 30 are flush with each other. It is formed in the cross-sectional shape of a ditch in the ceiling surface of. By holding the holding piece concave groove 51 of the second holder 50 and the convex portion 35 of the holding piece 30, the holding piece 30 can be advanced and retracted in conjunction with the advance and retreat of the second holder 50.

  The holder recessed groove 52 is formed in a recessed groove cross-sectional shape at the rear end portions of both inner wall surfaces parallel to the X direction so as to be hookable on the projecting portions 42 on both outer wall surfaces of the first holder 40. The formation range of the recessed groove 52 for the holder is determined so that the convex portion 42 of the first holder 40 is hooked on the recessed groove 52 for the holder after the molding piece 20 is detached from the undercut portion P1 at the time of mold release.

  The ridges 53 are formed in parallel to the X direction at the lower ends of both side walls parallel to the X direction, and slidably engage with second dovetail grooves 62 of the guide block 60 described later. The protrusion 53 is formed so that a step is generated between the front end face of the protrusion 53 and the front end face of the second holder 50, and the front end face of the protrusion 53 when the second holder 50 moves forward to the molding position. Is hooked on a convex portion 65 of a guide block 60 described later. As in the case of the protrusion 37 of the holding piece 30 and the dovetail groove 27 of the forming piece 20, a linear guide or the like can be used instead of the protrusion 43 and the second dovetail groove 62, for example.

  The insertion hole 54 is pierced in the center of the rear end surface so that the spring guide pin 100 is inserted and the spring 90 is not inserted so that the center axis coincides with the center axis of the insertion hole 44 of the first holder 40. Yes. The circular groove 55 is formed by expanding the insertion hole 54 in the rear inner wall surface so that the spring 90 can be accommodated, and the bottom surface of the circular groove 55 serves as a pressure receiving surface of the spring 90.

  A mounting hole 56 for fixing to the connecting plate 110 is formed at the center of the rear end surface. The attachment holes 57 for fixing to the slide block 120 are formed in four places on the upper surface. The mounting holes 56 and 57 are formed on the female side of the fastening member in accordance with the fastening member such as a screw or a knock pin used. Further, the number and arrangement of the mounting holes 56 and 57 are not limited to specific ones.

  The guide block 60 is a block member fixed to the fixed mold 11, and guides the first holder 40, the second holder 50, and the slider 80 in the X direction, and guides the stopper 70 up and down.

  The guide block 60 guides the first dovetail groove 61 for guiding the first holder 40, the second dovetail groove 62 for guiding the second holder 50, the third dovetail groove 63 for guiding the slider 80, and the stopper 70. A stopper guide 64 is formed, and a convex portion 65 is formed which comes into contact with the front end surfaces of the protrusions 43 and 53 of the first holder 40 and the second holder 50 and functions as a stopper (see FIG. 8).

  The first dovetail groove 61 is formed in the center of the upper surface in parallel with the X direction. The 2nd dovetail groove 62 is formed in the both ends of the upper surface in parallel with respect to the X direction. The third dovetail groove 63 is formed in the center of the bottom surface of the first dovetail groove 61 in parallel with the X direction.

  The stopper guide 64 is formed in a concave groove cross-sectional shape on both side surfaces in the middle of the third dovetail groove 63. The formation position of the stopper guide 64 is determined so that when the first holder 40 is advanced to the molding position, the concave groove 46 and the stopper guide 64 are in communication with the formation position of the concave groove 46 of the first holder 40. ing.

  The convex portion 65 is formed on the front end portion of the upper surface of the guide block 60 over the entire width in parallel to the Z direction. When the first holder 40 and the second holder 50 are advanced to the molding position, the first holder 40 and the second holder 50 function as a stopper by abutting and engaging with the front end surfaces of the protrusions 43 and 53.

  The stopper 70 is slidably engaged with the slider 80 while being fitted to the stopper guide 64 of the guide block 60 so as to be movable up and down, and moves up and down in the stopper guide 64 in conjunction with the advance and retreat of the slider 80. When the first holder 40 moves forward to the molding position, the first holder 40 is fitted into the concave groove 46 of the first holder 40, and the first holder 40 is stopped.

  The stopper 70 is a block piece formed with a dovetail groove 71 slidably engaged with a second protrusion 83 of a slider 80, which will be described later, and its lower surface is inclined at the same angle as an inclined surface 82 of the slider 80, which will be described later. (See FIG. 8).

  The slider 80 is attached to the connecting plate 110, slidably engages with the guide block 60 and the stopper 70, and moves the stopper 70 up and down by moving forward and backward in the X direction.

  The slider 80 includes a first protrusion 81 that is slidably engaged with the third dovetail groove 63 of the guide block 60, an inclined surface 82 that is a sliding surface with the stopper 70, and a slide with the dovetail groove 71 of the stopper 70. It is a block member in which a second protrusion 83 that is movably engaged and an attachment hole 84 for attachment to the connecting plate 110 are formed (see FIG. 8).

  The 1st protrusion 81 is formed in the lower end part of the both sides parallel to the X direction over the full length in parallel with the X direction. As in the case of the protrusion 37 of the holding piece 30 and the dovetail 27 of the forming piece 20, a linear guide or the like may be used instead of the first protrusion 81 and the third dovetail 63, for example.

  The inclined surface 82 is formed on the upper surface so as to be gradually inclined downward from the rear end to the front end. The inclination angle of the inclined surface 82 is such that the stopper 70 fits into the recessed groove 46 of the first holder 40 at the molding position, and the stopper 70 is recessed from the undercut portion P1 after releasing from the undercut portion P1. It is determined so as to be separated from the groove 46.

  The second protrusion 83 is formed on the entire inclined surface 82 so as to be slidably engaged with the dovetail groove 71 of the stopper 70. As in the case of the protrusion 37 of the holding piece 30 and the dovetail 27 of the forming piece 20, a linear guide or the like can be used instead of the second protrusion 83 and the dovetail 71, for example.

  The mounting hole 84 is formed on the rear end surface as a female side of the fastening member in accordance with a fastening member such as a screw or a knock pin to be used.

  The spring 90 is a compression coil spring, and is received in the round grooves 45 and 54 of the first holder 40 and the second holder 50 so as to push the first holder 40 forward, and the bottom surfaces of the round grooves 45 and 54 serving as pressure receiving surfaces. A force in the opposite direction is applied to each (see FIG. 10).

  The spring guide pin 100 is a cylindrical member, and is inserted through the spring 90 to guide the spring 90 in the X direction (see FIG. 9). The front end of the spring guide pin 100 is fitted into the groove 36 of the holding piece 30, and a mounting hole 101 for mounting to the connecting plate 110 is formed on the rear end surface, and the insertion hole 44 of the first holder 40 and It is inserted into the insertion hole 54 of the second holder 50 and fixed to the connecting plate 110. The mounting hole 101 is formed on the female side of the fastening member in accordance with a fastening member such as a screw or a knock pin to be used.

  The connecting plate 110 is a rectangular plate material, and connects the second holder 50, the slider 80, and the spring guide pin 100 (see FIG. 9). As a result, the second holder 50, the slider 80, and the spring guide pin 100 advance and retreat simultaneously with the same stroke. The connecting plate 110 is formed with three insertion holes 111 through which fastening members such as screws and knock pins are inserted in accordance with the positions of the mounting holes 56, 84, and 101 of the second holder 50, the slider 80, and the spring guide pin 100. ing.

  The slide block 120 is connected to the second holder 50, accommodates the second holder 50, the guide block 60, and the connecting plate 110, and advances and retreats in the X direction in conjunction with the vertical movement of the movable mold 12 via the angular pin 140. . The slide block 120 is a box-like member having an open bottom surface and a front end surface, and is formed to a size that can accommodate the second holder 50, the guide block 60, and the connecting plate 110 (see FIG. 10).

  The slide block 120 includes a convex portion 121 that fits into the slide rail 130, an inclined surface 122 that contacts a locking block (not shown) of the movable mold 12, a guide hole 123 that guides the angular pin 140, and a second holder 50. And an insertion hole 124 through which a fastening member for fastening is inserted.

  The convex portion 121 is formed in parallel to the X direction at the lower end portions of both outer wall surfaces parallel to the X direction. The inclined surface 122 is formed at the rear end portion, and abuts against a locking block attached to the movable mold 12 so that the slide block 120 does not move during molding. The guide hole 123 is formed in the flat plate portion 125 formed at the tip of the inclined surface 122 at the same angle as the mounting angle of the angular pin 140 so as to guide and guide the angular pin 140. The insertion holes 124 are formed in four places on the upper surface in accordance with the positions of the mounting holes 57 of the second holder 50.

  The slide rail 130 is two rail members attached to the fixed mold 11 and guides the slide block 120 in the X direction (see FIG. 10). In each of the two slide rails 130, a rectangular groove 131 into which the convex portion 121 of the slide block 120 is fitted is formed in parallel to the X direction at the lower end portion of the side surface on the slide block 120 side. In place of the convex portion 121 and the square groove 131, for example, a linear guide or the like can be used. The slide rail 130 is provided with three insertion holes 132 through which fastening members (not shown) for fixing to the fixed mold 11 are inserted.

  The angular pin 140 is a cylindrical pin that is attached to the movable mold 12 at an inclination, and slides in the guide hole 123 of the slide block 120 in conjunction with the vertical movement of the movable mold 12, so that the slide block 120 is moved to the X direction. Move forward and backward in the direction. The angular pin 140 has a tilt angle and a stroke that slides in the guide hole 123 so that the slide block 120 can move to the molding position when the movable die 12 is lowered to the lower end.

  Next, the operation of the molding die apparatus 1 of the present embodiment will be described with reference to FIGS. In the description, the molding die 10 is used as an injection molding die. At the time of molding, the movable mold 12 descends from the mold open state (see FIGS. 5 and 6) to the descending end and enters the mold closed state (see FIGS. 1 and 2). When the movable mold 12 is lowered, the angular pin 140 is inserted into the guide hole 123 of the slide block 120 and slides in the guide hole 123, whereby the slide block 120 moves forward and is connected to the slide block 120. Advances (moves from FIGS. 5 and 6 to the states of FIGS. 3 and 4).

  When the second holder 50 advances, the slider 80 and the spring guide pin 100 connected to the second holder 50 through the connecting plate 110 and the spring 90 accommodated in the circular groove 55 of the second holder 50 advance simultaneously. As the slider 80 moves forward, the stopper 70 slides along the inclined surface 82 and moves up in the stopper guide 64 of the guide block 60. Further, the first holder 40 is pushed into the spring 90 and moves forward with the molding piece 20 and the holding piece 30 placed thereon.

  The molding piece 20 advances together with the first holder 40 because the convex portion 24 is fitted in the molding piece guide 47 of the first holder 40. The holding piece 30 is pushed forward by the holding piece concave groove 51 of the second holder 50 latched on the convex portion 35 and the spring guide pin 100 fitted in the groove 36, but the first holder Until 40 abuts on the convex portion 65 of the guide block 60 and stops, it moves forward integrally with the first holder 40, and remains stationary in the first holder 40.

  The first holder 40 stops when the front end surface of the protrusion 43 comes into contact with the convex portion 65 of the guide block 60 and is hooked (see FIGS. 3 and 4). The second holder 50 (slide block 120) further advances, and the holding piece 30 moves forward along the holding piece guide 41 in the first holder 40 (FIGS. 3, 4 to 1, 2). Move to state). When the holding piece 30 advances in the first holder 40, the forming piece 20 (the divided pieces 21 and 22) slides along the inclined surfaces 23 and 32 so as to be pushed into the holding piece 30, and is guided to the forming piece guide 47. And move in the Z direction.

  When the movable mold 12 is lowered to the lower end, the molding piece 20 moves until the divided pieces 21 and 22 come into contact with each other, and the shaping piece 20 is completely accommodated in the notch 31 of the holding piece 30. Further, the front end surface of the protrusion 53 of the second holder 50 comes into contact with the convex portion 65 of the guide block 60 and the second holder 50 (slide block 120) comes to a standstill, and the holding piece 30, the first holder 40, and the second holder 50. The front end surface of the slide block 120 is flush with the front end surface of the guide block 60. Further, the stopper 70 is fitted into the concave groove 46 of the first holder 40. This state is a mold closed state (see FIGS. 1 and 2). The molding material is injected with the mold closed, and the molded product P is molded. At the time of molding, movement (retraction) of the slide block 120 is prevented by a locking block (not shown) of the movable mold 12.

  When the molded product P is cured, mold release (mold release) is started. When the movable mold 12 is raised, the slide block 120 is retracted via the angular pin 140 and the second holder 50 is retracted (moved from the state shown in FIGS. 1 and 2 to FIGS. 3 and 4). At the same time as the second holder 50 moves backward, the slider 80 and the spring guide pin 100 connected to the second holder 50 via the connecting plate 110 move backward. Further, the stopper 70 slides and descends along the inclined surface 82 of the slider 80, and the holding piece 30 hooked in the holding piece concave groove 51 of the second holder 50 is pulled by the second holder 50 and moves backward. To do.

  At this time, since the first holder 40 is stationary until the convex portion 42 of the first holder 40 is engaged with the holder groove 52 of the second holder 50, the holding piece 30 holds the inside of the first holder 40. Retreat along the piece guide 41. When the holding piece 30 moves backward in the first holder 40, the forming piece 20 that is slidably engaged with the holding piece 30 is pulled by the holding piece 30 and slides along the inclined surfaces 23 and 32, and is divided. The pieces 21 and 22 are moved in the Z direction along the forming piece guide 47 of the first holder 40 so that the pieces 21 and 22 are separated from each other, and the undercut portion P1 is punched (see FIGS. 3 and 4).

  When the undercut portion P1 is removed from the mold, the first holder 40 is slightly pulled by the holding piece 30 via the molding piece 20, but the first holder 40 is surely stationary by the action of the stopper 70 and the spring 90. To do.

  The molding piece 20 is disengaged from the undercut portion P1, the die cutting of the undercut portion P1 is completed, the stopper 70 is disengaged from the concave groove 46 of the first holder 40, and the convex portion 42 of the first holder 40 is the second holder 50. The first holder 40 is retracted by being hooked in the holder concave groove 52, and the protruding portion P2 is punched (moved from the state shown in FIGS. 3 and 4 to FIGS. 5 and 6). When the movable mold 12 rises to the rising end, the mold release is completed and the mold is opened, and the molded product P can be removed (see FIGS. 5 and 6). After the mold release is completed and the molded product P is taken out, the mold is closed again to form the next molded product P (return to FIGS. 1 and 2).

  As described above, according to the molding die device 1 of the present embodiment, since the undercut portion P1 can be punched while the molded body P3 is supported, the molded product P is damaged during die cutting. Can be reliably prevented.

  In addition, according to the molding die device 1 of the present embodiment, the undercut processing mechanism 13 is configured to perform the die cutting direction of the undercut portion P1 so that the divided pieces 21 and 22 constituting the molding piece 20 are separated from each other during die cutting. Therefore, it is possible to cope with a complicated undercut portion P1 such as a protrusion formed on the outer peripheral surface of the protruding portion P2.

  Further, according to the molding die device 1 of the present embodiment, the holding piece 30 and the first holder 40 can be advanced and retracted by using the reciprocating movement of the movable die 12 as a drive source by the action of the angular pin 140, which is energy saving. It can be manufactured inexpensively and compactly.

  Further, according to the molding die apparatus 1 of the present embodiment, the stopper 70 can reliably prevent the movement of the first holder 40 when the holding piece 30 is retracted. Damage to P can be prevented more reliably.

  Further, according to the molding die device 1 of the present embodiment, the undercut processing mechanism 13 has the molding piece 20 composed of the two divided pieces 21 and 22 and the shape of the shaping piece 20 and the holding piece 30 is also simple. Processing is easy and can be manufactured at low cost.

  Moreover, according to the molding die apparatus 1 of the present embodiment, the undercut processing mechanism 13 includes the cavity 25 and the core pin 34, and also functions as a molding core. For this reason, the undercut processing mechanism 13 can be rephrased as a molded core having an undercut processing function. Such a molded core is very useful because it is possible to perform die cutting of the undercut portion P1 without providing an undercut processing mechanism separately.

  FIG. 11 is a cross-sectional perspective view showing a state during molding of the molding die apparatus 2 according to the second embodiment of the present invention. FIG. 12 is a cross-sectional perspective view showing a state in the middle of mold release of the molding die apparatus 2 of FIG. FIG. 13 is a cross-sectional perspective view showing a state after release of the molding die device 2 of FIG. The same components as those in the molding die device 1 of the first embodiment shown in FIGS. 1 to 10 are denoted by the same reference numerals, and description thereof is omitted.

  The molding die device 2 of the present embodiment has the same basic configuration as the molding die device 1 of the first embodiment, but the shape of the molded product P10 to be molded is different. The shapes of the fixed mold 201 of the mold 200, the first holder 210 of the undercut processing mechanism 205, the guide block 220, the slide block 230, and the direction of the slider 80 are different.

  The molded product P10 molded by the molding die device 2 of the present embodiment has a projection P2 sandwiched between the molded product P molded by the molding die device 1 of the first embodiment, in addition to the projection P2. A total of four ribs P14 are provided for each of the upper and lower two protruding from the molded product body P3 in the X direction over the Z direction of the molded product body P3.

  A concave groove 203 into which the stopper 70 is fitted at the time of molding is formed on the upper surface of the fixed mold 201.

  The first holder 210 does not have the protrusion 43 and the concave groove 46 and is fixed to the guide block 220 with a fastening member such as a bolt.

  The guide block 220 does not have the first dovetail 61 and is formed in a concave groove shape in the Z direction on the front end surface so as to form the two ribs P14 on the lower side of the molded product P10. The first holder 210 and the first holder 210 are fixed to each other by a fastening member such as a bolt, and advance and retract in the X direction at the same timing as the first holder 210 (integrally). In the molding die device 2 of the present embodiment, the first holder 210 and the guide block 220 may be integrally formed.

  The third dovetail groove 63 of the guide block 220 is formed so as to be able to advance and retreat in the X direction in a state where the slider 80 is turned upside down with respect to the direction in the molding die device 1 of the first embodiment. The stopper guide 64 is formed on the lower surface, and is formed at a position communicating with the concave groove 203 formed on the upper surface of the fixed mold 201 when the guide block 220 moves to the molding position together with the first holder 210. Yes.

  The slide block 230 has two cavities 231 formed in a groove shape in the Z direction on the front end surface so as to mold the two upper ribs P14 of the molded product P10.

  Next, the operation of the molding die apparatus 2 of the present embodiment will be described with reference to FIGS. In addition, description is abbreviate | omitted about the same content as the molding die apparatus 1 of 1st Embodiment. At the time of molding, the movable mold 12 (not shown) is lowered from the mold open state (see FIG. 13) to the lower end and is in the mold closed state (see FIG. 11). At this time, the stopper 70 slides along the inclined surface 82 of the slider 80 as the slider 80 moves forward, descends in the stopper guide 64 of the guide block 220, and a part of the stopper 70 fits into the concave groove 203 of the fixed mold 201. . Thereby, the guide block 220 is fixed so as not to move with respect to the fixed mold 201.

  When the molded product P10 is cured and mold release (mold release) is started and the movable mold 12 is raised, the second holder 50, the holding piece 30, the slider 80, the spring guide pin 100 (with the slide block 230 via the angular pin 140 ( And the connecting plate 110) is retracted, and the stopper 70 is lifted and removed from the concave groove 203 of the fixed mold 201 (moved from the state shown in FIG. 11 to FIG. 12). At this time, similarly to the molding die device 1 of the first embodiment, the undercut portion P1 is die-cut, but the first holder 210 and the guide block 220 are not retracted and the molded product P10 (molded product main body P3 and Since the lower rib P14) is supported, the molded article P10 is prevented from being damaged.

  When the movable mold 12 is further raised from the state shown in FIG. 12, the second holder 50 is hooked on the first holder 210, and the first holder 210 and the guide block 220 fixed to the first holder 210 start to retreat. Then, the projecting portion P2 and the lower rib P14 are punched out. When the movable mold 12 rises to the rising end, the mold release is completed and the mold is opened (see FIG. 13).

  As described above, according to the molding die device 2 of the present embodiment, not only the protruding portion P2 having the undercut portion P1, but also, for example, the molded product P10 having the ribs P14 above and below the protruding portion P2. In addition, it is possible to perform molding and die cutting of a molded product having ribs that are formed to protrude from the same plane as the protruding portion P2. Even when the molded product P10 is molded and die-cut, the molded product P10 can be supported by the first holder 210 and the guide block 220 when the undercut portion P1 is die-cut. Damage and deformation are prevented.

  As described above, the undercut processing mechanism and the molding die of the present invention have been described using the molding die apparatuses 1 and 2 of the first and second embodiments. However, the undercut processing mechanism and the molding die of the present invention have been described. A type | mold is not limited to the said embodiment, It can deform | transform and use in the range which does not change a summary. For example, without using a core pin, it is also possible to form a protruding part without a hollow part in a molded product.

  Further, in the molding die apparatuses 1 and 2 of the first and second embodiments, the fixed molds 11 and 201 and the movable mold 12 may be reversed. That is, in the mold apparatus 1 and 2 according to the first and second embodiments, the mold plate called the fixed molds 11 and 201 moves up and down, and the mold plate called the movable mold 12 does not move. There may be.

  In the undercut processing mechanism of the present invention, the molding piece may be composed of three or more divided pieces. At this time, the holder and the holding piece may be changed in shape according to the number, shape, and arrangement of the divided pieces. For example, the forming piece guide of the holder is formed so that each divided piece can be guided in the die cutting direction of the undercut portion. In addition, the holding piece is formed with a notch that can accommodate all the divided pieces without any gap, and the notch is formed with one or more inclined surfaces and engaging means, and each inclined surface is engaged with each other. It is formed so that the inclined surface of the sliding split piece coincides with the inclined direction.

  Further, in the undercut processing mechanism of the present invention, the method of moving the holding piece 30 and the first holders 40 and 210 is the same as the second holder 50, like the molding die apparatuses 1 and 2 of the first and second embodiments. The method is not limited to the method using the slide blocks 120 and 230, the angular pins 140, and the like. For example, a linear motion cylinder (not shown) that is driven by hydraulic pressure or the like is connected to the holding piece 30 and / or the first holders 40 and 210. It is also possible to adopt a method of moving them. However, when the second holder 50, the slide blocks 120 and 230, the angular pin 140, etc. are used like the molding die apparatuses 1 and 2 of the first and second embodiments, compared to the case where the linear motion cylinder is used, It is energy saving and can be manufactured inexpensively and compactly.

  Further, the molded product (undercut portion) that can be molded by the undercut processing mechanism and the molding die of the present invention is not limited to those exemplified in the first and second embodiments, and for example, FIG. a row of two or more protrusions P2 as shown in a), a so-called bamboo shoot nipple having an undercut portion P15 formed with a plurality of tapered portions as shown in FIG. A nipple having a plurality of arc-shaped undercut portions P16 as shown in FIG. 14 (c) and an inlet having an undercut portion P17 as shown in FIG. 14 (d) for supplying grease. A so-called grease nipple or the like can be formed.

  Further, as shown in FIGS. 15A and 15B, a molded product having ribs P24 that protrude from the surface of the molded product body P23 on which the projecting portion P2 is formed and that are formed horizontally above and below the projecting portion P2. It is also possible to mold P20. FIG. 15B is a longitudinal sectional view of FIG. Further, as shown in FIG. 15C, in addition to the upper and lower ribs P24, it is also possible to mold a molded product P30 having ribs P34 formed perpendicularly to the left and right of the protruding portion P2. In addition, the shape and arrangement | positioning of the rib which can be shape | molded are not limited to what was mentioned above.

  As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will readily understand various changes and modifications within the obvious scope by looking at the present specification. Therefore, such changes and modifications are interpreted as being within the scope of the invention defined by the claims.

10, 200 Mold 11, 201 Fixed mold 12 Movable mold 13, 205 Undercut processing mechanism 20 Molding piece 21, 22 Split piece 23, 32 Inclined surface 25 Cavity 27 Dovetail groove 30 Holding piece 34 Core pin 37 Projection 40, 210 First holder 41 Holding piece guide 47 Molding piece guide 50 Second holder 70 Stopper 140 Angular pin P Molded product P1 Undercut part P2 Projection part P3 Molded product body

Claims (9)

An undercut processing mechanism capable of molding an undercut part, which is used by being attached to a molding die having a fixed mold and a movable mold for molding a molded product having an undercut part,
A molding piece composed of two or more divided pieces for molding the outer peripheral surface of the undercut portion;
A holding piece that slidably engages with the forming piece and opens and closes the forming piece;
An advanceable / retractable holder for accommodating the holding piece in an advanceable / retractable manner,
The holding piece is capable of moving back and forth in the holder while the holder is stationary.
The molding piece and the holding piece both have an inclined surface, and are slidably engaged via engagement means provided on the inclined surface,
The holder has a molding piece guide that guides the molding piece in a die-cutting direction of the undercut portion,
When the holding piece is completely accommodated in the holder, the divided pieces come into contact with each other to form the outer peripheral surface of the undercut portion, and when the holding piece is retracted, the divided pieces are mutually connected. Move along the molding piece guide so that the
The undercut processing mechanism is characterized in that the holder is stationary in a state where the molded product is supported until the molding piece is removed from the undercut portion. Furthermore, the holding piece and the drive means for advancing and retracting the holder,
The undercut processing mechanism according to claim 1, wherein the driving unit is capable of moving the holding piece forward and backward in the holder while the holder is stationary. Furthermore, an angular pin attached to the fixed mold or the movable mold,
The angular pin is disposed obliquely with respect to the moving direction of the movable type,
3. The holding piece and the holder can be moved back and forth in a direction different from the moving direction of the movable type in conjunction with the reciprocating movement of the movable type via the angular pin. Undercut processing mechanism.   The undercut processing mechanism according to any one of claims 1 to 3, further comprising a stopper that stops the holder when the holding piece is retracted in the holder. Each of the two or more divided pieces has a cavity for molding the outer peripheral surface of the undercut portion on the inner surface, and has the inclined surface on the outer surface,
The holding piece has two or more inclined surfaces, and the inclined direction of each inclined surface is formed so as to coincide with the inclined direction of the inclined surfaces of the divided pieces that slide with each other. The undercut processing mechanism according to any one of claims 1 to 4. The molded product having the undercut portion is a molded product having a protruding portion protruding in a direction different from the moving direction of the movable mold from the molded product main body,
The undercut portion is a protrusion formed on the outer peripheral surface of the protrusion,
The protrusion is orthogonal or inclined with respect to the molded product body,
The holder has a holding piece guide for guiding the holding piece at the same angle as the protruding portion,
The undercut processing mechanism according to claim 1, wherein the holding piece moves along the holding piece guide. The molded product having the undercut portion is a molded product having a tubular projecting portion projecting from the molded product body in a direction different from the moving direction of the movable mold,
The undercut portion is a protrusion formed on the outer peripheral surface of the protrusion,
The undercut processing mechanism according to claim 1, wherein a core pin for forming an inner peripheral surface of the protruding portion is attached to the holding piece. The molded product having the undercut portion is a molded product having one or more ribs that are molded by projecting from the same plane as the projecting portion,
8. One or more cavities formed in one or more members that move in the same direction as the protruding direction of the ribs to form the ribs, according to claim 1. Undercut processing mechanism. Fixed type,
Movable type,
The undercut processing mechanism according to any one of claims 1 to 8,
A mold for molding, comprising:

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