JP6999928B2 - Undercut processing mechanism and molding mold - Google Patents

Description

The present invention relates to an undercut processing mechanism and a molding die attached to and used for a molding die for molding a molded product having an undercut portion.

In a molding die for molding a molded product having an undercut portion, many undercut processing mechanisms have been developed in a form corresponding to the form of the undercut portion. As the undercut processing mechanism, for example, a loose core is generally used.

Further, when molding a molded product that is difficult to mold by a conventional undercut processing mechanism using a loose core, for example, a molded product in which a boss having a hollow portion protrudes in a direction intersecting the die cutting direction of the entire molded product. The applicant has already proposed an undercut processing mechanism that makes it possible to easily die-cut a boss that becomes an undercut portion (see, for example, Patent Document 1).

The undercut processing mechanism described in Patent Document 1 includes a holder internally installed in a fixed or movable mold of a molding die, and a molding core for molding the undercut portion, and the molding core is a first core and a first core. It is composed of two cores, and the first core and the second core have inclined side surfaces adjacent to each other, and the undercut portion can be die-cut by sliding in the holder along the side surfaces.

Japanese Unexamined Patent Publication No. 2010-155381

According to the undercut processing mechanism described in Patent Document 1, the molding of a molded product having a shape that was difficult to form by the conventional undercut processing mechanism using a loose core is facilitated, and a support rod, a guide rod, or the like is not required. Therefore, it can be configured more compactly than the undercut processing mechanism using a conventional loose core.

The present invention realizes simplification and compactness of molding of a molded product having an undercut portion like the undercut processing mechanism described in Patent Document 1 in a configuration different from the undercut processing mechanism described in Patent Document 1. It proposes a possible undercut processing mechanism, a molding die, and a molded product.

An object of the present invention is to provide an undercut processing mechanism and a molding die that can be compactly configured and that can easily cut out an undercut portion.

INDUSTRIAL APPLICABILITY The present invention is used by attaching to a molding die for molding a molded product having an undercut portion, and the undercut portion that protrudes in a direction intersecting the die cutting direction of the molded product can be die-cut. A holder for accommodating at least a part of a sliding piece and a holding piece, which is a cutting processing mechanism and is attached to the molding die so as to be movable in the die cutting direction of the molded product, and slides with respect to the holder. It is possible to form the sliding piece that forms the undercut portion, and the holding piece that is fixed or integrally formed to the molding die so as to hold the sliding piece slidably. The sliding piece is configured to move in a direction in which the undercut portion can be die-cut by moving the holder in the die-cutting direction of the molded product when the molded product is die-cut. It is a characteristic undercut processing mechanism.

Further, in the undercut processing mechanism of the present invention, the sliding piece and the holding piece are characterized in that they are arranged side by side in the moving direction of the holder and are adjacent to each other.

Further, in the undercut processing mechanism of the present invention, the holder is configured to project the molded product during the projecting operation of the molded product.

Further, in the undercut processing mechanism of the present invention, the holder and the holding piece are each provided with a regulating means for restricting the moving direction of the sliding piece in a direction in which the undercut portion can be die-cut.

Further, in the undercut processing mechanism of the present invention, the restricting means of the holder engages with the sliding piece so that the sliding piece can slide in a direction in which the undercut portion can be die-cut with respect to the holder. The restricting means of the holding piece is provided so as to engage with the sliding piece so that the sliding piece can slide in a direction orthogonal to the direction in which the undercut portion can be die-cut with respect to the holding piece. It is characterized in that it is provided as such.

Further, in the undercut processing mechanism of the present invention, the sliding piece is a molding member that forms a hollow portion or a space portion of the undercut portion so that a molded product having a hollow portion or a space portion in the undercut portion can be molded. It is characterized by having.

Further, in the undercut processing mechanism of the present invention, the sliding piece is composed of a plurality of divided sliding pieces, and at least two of the plurality of sliding pieces are each of the holder when the holder is moved. It is characterized in that it is configured to move in a direction different from the moving direction of and in a direction different from each other.

Further, the undercut processing mechanism of the present invention is further provided with an outer holder that is fixed to the molding die and slides the holder in order to prevent wear of the molding die.

Further, in the undercut processing mechanism of the present invention, the holder is formed in a tapered shape in part or all of the outer peripheral surface which is a sliding surface and / or in order to prevent wear of the molding die. It is characterized by being.

Further, the present invention is a molding die provided with the undercut processing mechanism.

According to the undercut processing mechanism and the molding die of the present invention, when the holder moves in the die-cutting direction of the molded product, the sliding piece slides with respect to the holder and the undercut portion can be die-cut. Since it moves, the undercut portion can be easily die-cut while being compactly configurable.

It is sectional drawing at the time of mold clamping of the molding die 1 of the 1st Embodiment of this invention. It is sectional drawing after opening of the mold 1 for molding of FIG. It is sectional drawing after the sticking-out operation of the molded product P of the molding die 1 of FIG. It is a perspective view of the undercut processing mechanism 10 of the molding die 1 of FIG. It is an exploded perspective view of the undercut processing mechanism 10 of the molding die 1 of FIG. It is a perspective view which shows an example of the molded article which can be molded by the undercut processing mechanism of this invention and a molding die. It is sectional drawing at the time of mold clamping of the molding die 2 of the 2nd Embodiment of this invention. FIG. 7 is a cross-sectional view of the molding die 2 of FIG. 7 after opening. FIG. 7 is a cross-sectional view of the molded product P10 of the molding die 2 of FIG. 7 after the ejection operation. It is a perspective view of the undercut processing mechanism 14 of the molding die 2 of FIG. 7. It is an exploded perspective view of the undercut processing mechanism 14 of the molding die 2 of FIG. 7. FIG. It is a figure which shows an example of the molded article which can be molded by the undercut processing mechanism of this invention, and a molding die. It is a figure which shows an example of the molded article which can be molded by the undercut processing mechanism of this invention, and a molding die. It is a figure which shows an example of the molded article which can be molded by the undercut processing mechanism of this invention, and a molding die. It is a figure which shows an example of the molded article which can be molded by the undercut processing mechanism of this invention, and a molding die. It is a figure which shows an example of the molded article which can be molded by the undercut processing mechanism of this invention, and a molding die. It is sectional drawing at the time of mold clamping of the molding die 3 of the 3rd Embodiment of this invention. It is sectional drawing after opening of the mold 3 for molding of FIG. It is sectional drawing after the sticking-out operation of the molded product P10 of the molding die 3 of FIG. It is a partial decomposition perspective view of the undercut processing mechanism 16 of the molding die 3 of FIG. It is sectional drawing at the time of mold clamping of the molding die 4 of the 4th Embodiment of this invention. FIG. 21 is a cross-sectional view of the molding die 4 of FIG. 21 after opening. FIG. 21 is a cross-sectional view of the molded product P10 of the molding die 4 of FIG. 21 after the ejection operation. It is a partial decomposition perspective view of the undercut processing mechanism 18 of the molding die 4 of FIG. 21.

1 is a cross-sectional view of the molding die 1 of the first embodiment of the present invention, FIG. 2 is a cross-sectional view of the molding die 1 of FIG. 1 after opening, and FIG. 3 is for molding of FIG. A cross-sectional view of the molded product P of the mold 1 after the ejection operation, FIG. 4 is a perspective view of the undercut processing mechanism 10 of the molding mold 1 of FIG. 1, and FIG. 5 is a perspective view of the molding mold 1 of FIG. It is an exploded perspective view of the undercut processing mechanism 10. Note that FIG. 4 shows only the cross section of the holder 20.

The molding die 1 of the first embodiment of the present invention has a fixed mold 100 for injecting a molding material to mold the outer surface side of the molded product P (see FIG. 1), and an inner surface including an undercut portion P1 of the molded product P. It has the same configuration as a known injection molding die including a movable mold 101 for molding the side, but is different from a known injection molding die in that it includes an undercut processing mechanism 10. For convenience, the fixed mold 100 side of FIG. 1 will be described as the top, and the movable mold 101 side will be described as the bottom.

In the molding die 1 of the present embodiment, similarly to the known injection molding die, the fixed mold 100 includes a fixed side mounting plate 103, a fixed side mold plate 104, a locating ring 105, and a sprue bush 106, and is a movable mold 101. Is equipped with a movable side mounting plate 107, a movable side mold plate 108, a spacer block 109, two ejector base plates 110, an ejector pin 111, a return pin 112, a spring 113, and an ejector rod 114. The base plate 110 moves with respect to the movable side mold plate 108 in the die cutting direction (upward direction in FIG. 1) of the molded product P, so that the ejector pin 111 pushes out the molded product P. Since the above components are the same as the known injection molding dies, the description thereof will be omitted.

Further, in the molding die 1 of the present embodiment, an undercut processing mechanism 10 that enables die cutting of the undercut portion P1 is incorporated in the movable die 101, and in addition to the ejector pin 111, an undercut process described later is performed. A holder ejector pin 12 for projecting the holder 20 of the mechanism 10 is erected on the ejector base plate 110.

The undercut processing mechanism 10 enables the undercut portion P1 to be die-cut from the molding die 1 when the molded product P is die-cut (protruded). In the present embodiment, the undercut portion P1 is a cylindrical boss protruding from the inner surface side of the molded product P in a direction intersecting the die cutting direction (upward direction in FIG. 1) of the molded product P. In the undercut processing mechanism, molding die, and molded product of the present invention, the undercut portion that can be molded and die-cut is not limited to the cylindrical boss as described later. The material of the molded product P is not limited to synthetic resin such as plastic, but may be metal such as iron, copper and aluminum.

The undercut processing mechanism 10 slides a cylindrical holder 20 that can reciprocate in the die-cutting direction of the molded product P, a sliding piece 21 slidably arranged in the holder 20, and the sliding piece 21. A holding piece 22 that can be held is provided, and the holder 20 moves in the die-cutting direction of the molded product P when the molded product P is die-cut, so that the sliding piece 21 is different from the die-cutting direction of the molded product P. The cut portion P1 is configured to move in a direction that allows die cutting.

Here, the direction in which the undercut portion P1 can be die-cut is the moving direction of the sliding piece 21 in which the sliding piece 21 comes off from the undercut portion P1 without deforming or damaging the undercut portion P1. Then, the sliding piece 21 corresponding to the central axis O of the cylindrical boss (undercut portion P1) is in the direction away from the undercut portion P1.

The holder 20 can be reciprocated in the die-cutting direction of the molded product P in conjunction with the ejector base plate 110 via the ejector pin 12 for the holder. The bottom surface is fixed to the tip of the ejector pin 12 for the holder, and the movable die 101 is movable. It is embedded in the side template 108. The holder 20 is not limited to a cylindrical shape, and may have, for example, a polygonal cylindrical shape in cross section.

Further, the holder 20 is formed and arranged so that the upper surface of the holder 20 is flush with the upper surface of the movable side mold 108 when the molding die 1 is clamped and is in contact with the inner surface of the molded product P during molding. As a result, the holder 20 molds the molded product P at the time of molding, and ejects the molded product P at the time of die cutting of the molded product P. Further, the holder 20 is formed and arranged so that a gap does not occur between the upper surface of the holder 20 and the upper surface of the movable side template 108 at the time of molding in order to prevent molding defects of the molded product P.

The hollow portion 31 of the holder 20 having a cylindrical shape is formed so as to be able to store the sliding piece 21 and the holding piece 22, and regulates the sliding direction of the sliding piece 21 in a direction in which the undercut portion P1 can be die-cut. It has an inclined inclined groove 30 as a means, has a convex shape in a plan view as shown in FIGS. 3 and 4, and has a gradually increasing cross-sectional area from the upper end to the lower end.

The inclined groove 30 engages with the protrusion 33 of the sliding piece 21 described later, and regulates the sliding direction of the sliding piece 21 in a direction in which the undercut portion P1 can be die-cut. It is provided parallel to O.

The sliding piece 21 is a piece that is slidable in the holder 20 along the slanted groove 30, and is slidably engaged with the slanted groove 30 so that the undercut portion P1 can be die-cut. 33, which is a regulating means for regulating the sliding direction of the undercut portion, a hollow portion 34 for forming the undercut portion P1, a pin 35 which is a forming member for forming the hollow portion of the undercut portion P1, and a holding piece 22. It has a dovetail groove 36 which is a regulating means for restricting the sliding direction of the sliding piece 21 in a direction in which the undercut portion P1 can be slidably engaged and die-cut, and as shown in FIG. Sometimes it has a convex shape in a plan view so that it fits snugly into the hollow portion 31 of the holder 20, and the cross-sectional area gradually increases from the upper end to the lower end.

Further, in order to prevent molding defects of the molded product P, the sliding piece 21 is between the upper surface of the sliding piece 21 and the upper surface of the holder 20 at the time of mold clamping, that is, when the sliding piece 21 is at the upper end of the holder 20. It is formed so that there is no gap in the.

The ridge 33 is provided so as to be inclined to the side surface of the sliding piece 21 so as to engage with the inclined groove 30 of the holder 20 and regulate the sliding direction of the sliding piece 21 in a direction in which the undercut portion P1 can be die-cut. Has been done.

The hollow portion 34 is a round hole provided on the upper surface of the sliding piece 21, and the pin 35 is arranged in the center of the hollow portion 34 and fixed to the sliding piece 21. The shape and arrangement of the hollow portion 34 and the pin 35 may be appropriately determined according to the shape of the undercut portion P1. Further, the pin 35 may be integrally formed in the hollow portion 34.

The dovetail groove 36 is provided on the bottom surface of the sliding piece 21 so as to slidably engage with the protrusion 38 of the holding piece 22 described later. The dovetail groove 36 (bottom surface of the sliding piece 21) is in a direction in which the undercut portion P1 can be die-cut so that the sliding piece 21 moves in a direction in which the undercut portion P1 can be die-cut in conjunction with the holder 20. It is inclined in a direction orthogonal to (the central axis O of the undercut portion P1).

The holding piece 22 is a piece that holds the sliding piece 21 so that the sliding piece 21 slides in conjunction with the holder 20, and the bottom surface is fixed to the movable side template 108. The holding piece 22 has a ridge 38 on the upper surface, which is a regulating means for regulating the sliding direction of the sliding piece 21 in a direction in which the undercut portion P1 can be die-cut. It is engaged with the groove 36.

The holding pieces 22 are arranged side by side in the moving direction of the holder 20 and adjacent to the sliding piece 21, and are arranged so as to be housed in the holder 20 together with the sliding piece 21 at the time of mold clamping. The sliding piece 21 and the holding piece 22 do not need to be completely housed in the holder 20 at the time of mold clamping and / or mold opening, and a part of the sliding piece 21 and the holding piece 22 may protrude from the holder 20. Further, the holding piece 22 may be integrally formed with the movable side template 108.

Similar to the dovetail groove 36 (bottom surface of the sliding piece 21), the ridge 38 (upper surface of the holding piece 22) moves the undercut portion P1 in a direction in which the sliding piece 21 is interlocked with the holder 20 so that the undercut portion P1 can be die-cut. As described above, the undercut portion P1 is inclined in a direction orthogonal to the direction in which the undercut portion P1 can be die-cut (the central axis O of the undercut portion P1).

Next, the operation of the molding die 1 of the present embodiment will be described. At the time of molding the molded product P, the molding material is injected from the sprue bush 106 of the fixed mold 100 in a state where the molding die 1 is molded, and the molding material is cured to mold the molded product P (see FIG. 1). At the time of molding, the upper surface of the holder 20 of the undercut processing mechanism 10 and the upper surface of the sliding piece 21 are flush with the upper surface of the movable side template 108 and are in contact with the molded product P (molding material) to perform molding. The hollow portion 34 and the pin 35 of 21 form the undercut portion P1 of the molded product P.

After molding the molded product P, the molding die 1 is opened. When the mold 1 for molding is opened, the entire movable mold 101 moves downward in FIG. 1, and the molded product P remains on the movable mold 101 side (see FIG. 2). After opening the molding die 1, the molded product P is projected. During the projecting operation of the molded product P, the ejector base plate 110 moves upward in FIG. 1.

In the undercut processing mechanism 10, as the ejector base plate 110 moves, the holder 20 protrudes from the upper surface of the movable side template 108 by the holder ejector pin 12, and the molded product P is projected upward in FIG. 1 together with the ejector pin 111. .. At the same time, due to the action of the slanted groove 30 of the holder 20, the ridge 33 and the dovetail groove 36 of the sliding piece 21, and the ridge 38 of the holding piece 22, the sliding piece 21 has the central axis O with respect to the undercut portion P1. It moves in the lower left direction of FIG. 1 along the line and deviates from the undercut portion P1.

As a result, when the ejection operation of the molded product P is completed, the sliding piece 21 is disengaged from the undercut portion P1, and the molded product P is projected from the movable side template 108 by the ejector pin 111 and the holder 20 (FIG. 3). reference). After taking out the molded product P, the molding die 1 is molded again in order to mold the next molded product P.

At the time of mold clamping, the entire movable mold 101 moves upward in FIG. 1, and the ejector base plate 110 moves downward in FIG. 1. In the undercut processing mechanism 10, the holder 20 is pulled into the movable side template 108 by the holder ejector pin 12 as the ejector base plate 110 moves, and at the same time, the inclined groove 30 and the sliding piece 21 of the holder 20 By the action of the ridge 33, the dovetail groove 36, and the ridge 38 of the holding piece 22, the sliding piece 21 moves along the oblique groove 30 of the holder 20, and the upper surface of the holder 20 and the upper surface of the sliding piece 21 are on the movable side. It is flush with the upper surface of the template 108. When the molding is completed, the molding material is injected and the next molded product P is molded.

As described above, according to the molding die 1 and the undercut processing mechanism 10 of the present embodiment, in the configuration in which the sliding piece 21 and the holding piece 22 are provided in the holder 20, the holder 20 is the molded product P. By moving in the die-cutting direction, the molded product P can be projected and the undercut portion P1 can be die-cut. Therefore, the undercut portion P1 can be easily die-cut while being compactly configurable.

Further, in the undercut processing mechanism 10 of the present embodiment, the sliding piece 21 and the holding piece 22 are adjacent to each other side by side in the moving direction of the holder 20 and are provided in the holder 20, so that the space required for installation is very large. It's small. Therefore, the undercut processing mechanism 10 is easily applied not only to the molding die 1 of the present embodiment but also to other molding dies.

Further, in the molding die 1 of the present embodiment, the ejector pin 111 is used for projecting the molded product P, but depending on the conditions such as the formation position and weight of the undercut portion P1 in the molded product P, only the holder 20 is used. It is also possible to project the molded product P, and it is also possible to further reduce the size and cost of the molding die 1.

The molded product that can be molded in the molding die of the present invention is not limited to the one in which the undercut portion is a cylindrical boss. 6 (a) and 6 (b) are perspective views showing an example of a molded product that can be molded by the undercut processing mechanism and the molding die of the present invention. The undercut processing mechanism of the molding die of the present invention is orthogonal to the die cutting direction of the molded product P, as in the first embodiment and the undercut portions P1, P2, and P3 shown in FIG. It has a hollow part or a space part formed by a molding member such as a pin 35, which cannot be die-cut with a conventional loose core that moves in the direction, and is parallel to the surface on which the undercut part protrudes in a vertical cross-sectional view. It can be suitably used for molding and die cutting of an undercut portion having a plurality of protruding portions arranged in the same direction.

7 is a cross-sectional view of the molding die 2 of the second embodiment of the present invention at the time of mold clamping, FIG. 8 is a cross-sectional view of the molding die 2 of FIG. 7 after opening, and FIG. 9 is a view. 7 is a cross-sectional view of the molded product P10 of the molding die 2 after the ejection operation, FIG. 10 is a perspective view of the undercut processing mechanism 10 of the molding die 2 of FIG. 7, and FIG. 11 is for molding of FIG. 7. It is an exploded perspective view of the undercut processing mechanism 10 of a mold 2. FIG.

The same components as those of the molding die 1 of the first embodiment shown in FIGS. 1 to 5 are designated by the same reference numerals, and the description thereof will be omitted. The molding die 2 of the second embodiment has the same basic configuration as the molding die 1 of the first embodiment, but has a configuration of the undercut processing mechanism 14 according to the shape of the molded product P10 to be molded. And the shape is different.

The molded product P10 has an undercut portion P11 which is a cylindrical boss protruding in a direction intersecting the die cutting direction, and has two locations at the base of the undercut portion P11 and a direction in which the undercut portion P11 can be die-cut. A hole P12 having a rectangular cross section, which is another undercut portion, is provided. In the undercut processing mechanism 14 of the molding die 2 of the present embodiment, the sliding piece is configured in a split type so that the undercut portion P11 having such a hole P12 can be molded.

The undercut processing mechanism 14 of the molding die 2 of the second embodiment is a holder slidable with respect to the movable side mold 108 like the undercut processing mechanism 10 of the molding die 1 of the first embodiment. 40, a holding piece 50 fixed to the movable side mold 108, and a split type sliding piece slidably arranged in the holder 40, the first sliding piece 61 and the second sliding piece. A piece 62 and a third sliding piece 63 are provided.

The holder 40 is configured to form a square tube by two half-split members having a symmetrical cross-section so that the sliding piece can be incorporated, and the first sliding piece 61 and the second sliding piece are formed on the inner surface. A horizontal groove 41 that guides the 62 and an oblique groove 42 that guides the third sliding piece 63 are provided. The holder 40 is composed of two members, but when the ejector base plate 110 is moved, the two members need to be configured to move integrally. Further, the holder 40 may be composed of three or more members.

The horizontal groove 41 is provided parallel to the drilling direction of the hole P12 so that the first sliding piece 61 and the second sliding piece 62 can move so that the undercut portion P11 and the hole P12 can be die-cut. .. That is, when the drilling direction of the hole P12 is not horizontal, the horizontal groove 41 is provided not horizontally but parallel to the drilling direction (die-cutting possible direction) of the hole P12.

The slanted groove 42 is undersized so that the third sliding piece 63 moves in the direction in which the pin 35 of the third sliding piece 63 comes out of the hollow portion of the undercut portion P11 when the ejector base plate 110 (holder 40) is raised. It is provided parallel to the protruding direction of the cut portion P11. The slanted groove 42 corresponds to the slanted groove 31 of the holder 20 in the molding die 1 of the first embodiment.

The holding piece 50 is a block member provided with a substantially trapezoidal notch, and the first sliding piece 61, the second sliding piece 62, and the third sliding piece 63 are slid on the end surface of the notched portion, respectively. A first ridge 51, a second ridge 52, and a third ridge 53 that are freely engaged and held are formed.

The first ridge 51, the second ridge, and the third ridge 53 are inclined with respect to the horizontal direction (horizontal direction in FIG. 7) and the vertical direction (vertical direction in FIG. 7). The inclination angles of the first ridge 51 and the second ridge are set to a position where the undercut portion P11 can be die-cut when the ejector base plate 110 (holder 40) is raised according to the stroke amount of the ejector base plate 110. It is determined that the 1 sliding piece 61 and the 2nd sliding piece 62 move. The inclination angle of the third ridge 53 is such that the third sliding piece 63 moves until the pin 35 of the third sliding piece 63 comes out of the hollow portion of the undercut portion P11 when the ejector base plate 110 (holder 40) rises. It is decided to. The third ridge 53 corresponds to the ridge 38 of the holding piece 22 in the molding die 1 of the first embodiment.

The sliding piece includes a first sliding piece 61 and a second sliding piece 62 for forming the outer surface of the undercut portion P11, and a third sliding piece 63 for forming the hollow portion of the undercut portion P11.

Each of the first sliding piece 61 and the second sliding piece 62 has a protrusion 65 for forming the hole P12 of the undercut portion P11 on the molding surface 64 which is in contact with the undercut portion P11 at the time of molding. In the undercut processing mechanism 14 of the molding die 2 of the present embodiment, the sliding piece is configured in a split type so that the protrusion 65 comes out of the hole P12 when the ejector base plate 110 (holder 40) is raised. ..

Further, the first sliding piece 61 has a dovetail groove 66 that engages with the first ridge 51 of the holding piece 50, and a ridge 67 that fits into the horizontal groove 41 of the holder 40, and the second sliding piece 62 holds the holding piece 62. It has a dovetail groove 66 that engages with the second ridge 52 of the piece 50, and a ridge 67 that fits into the horizontal groove 41 of the holder 40.

The first sliding piece 61 and the second sliding piece 62 are engaged with the first ridge 51 and the second ridge 52 of the holding piece 50, respectively, so that the molding surfaces 64 face each other. The first sliding piece 61 and the second sliding piece 62 have the first ridge 51 or the second ridge 52 that are engaged with each other when the ejector base plate 110 is moved, and the horizontal groove 41 of the holder 40, respectively. It slides in conjunction with the holder 40 along the line.

The third sliding piece 63 is a pair of sliding pieces that slidably engage the pin 35 for forming the hollow portion of the undercut portion P11 and the third ridge 53 of the holding piece 50 that sandwiches the pin 35. It is composed of a member 68. The third sliding piece 63 has a dovetail groove 69 in the sliding member 68 so that the pin 35 is sandwiched by the pair of sliding members 68 and at the same time slidably engaged with the third protrusion 53 of the holding piece 50. Is provided. Further, the sliding member 68 is formed so as to be slidably fitted into the oblique groove 42 of the holder 40.

Next, the operation of the molding die 2 of the present embodiment will be described. The same part as the operation of the molding die 1 of the first embodiment will be omitted. When molding the molded product P10, the upper surface of the holder 40 of the undercut processing mechanism 14 and the upper surfaces of the first sliding piece 61 and the second sliding piece 62 are flush with the upper surface of the movable side template 108. Molding is performed in contact with P10 (molding material), and the molding surface 64 of the first sliding piece and the second sliding piece 62 and the pin 35 of the third sliding piece 63 form the undercut portion P11 of the molded product P10. (See FIG. 7). After molding the molded product P10, the molding die 1 is opened (see FIG. 8).

After opening the molding die 2, the molded product P10 is projected. In the undercut processing mechanism 14, as the ejector base plate 110 moves, the holder 40 protrudes from the upper surface of the movable side template 108 by the holder ejector pin 12, and the molded product P is projected upward in FIG. 8 together with the ejector pin 111. .. At the same time, the first sliding piece 61 slides along the horizontal groove 41 of the holder 40 and the first ridge 51 of the holding piece 50, and the second sliding piece 62 slides along the horizontal groove 41 of the holder 40 and the holding piece. It slides along the second ridge 52 of 50, and the third sliding piece 63 slides along the oblique groove 42 of the holder 40 and the third ridge 53 of the holding piece 50.

As a result, when the ejection operation of the molded product P10 is completed, the first sliding piece 61, the second sliding piece 62, and the third sliding piece 63 are disengaged from the undercut portion P11 and the hole P12, and the ejector pin 111 and the holder 40 are used. The molded product P10 is in a state of being ejected from the movable side template 108 (see FIG. 9). After taking out the molded product P, the molding die 1 is molded again in order to mold the next molded product P.

At the time of mold clamping, the holder 40 is pulled into the movable side template 108 by the holder ejector pin 12 as the ejector base plate 110 is lowered, and at the same time, the horizontal groove 41, the oblique groove 42, and the holding piece 50 of the holder 40 are the first. Action of 1 ridge 51, 2nd ridge 52 and 3rd ridge 53, and dovetail grooves 66, 69 and ridge 67 of 1st sliding piece 61, 2nd sliding piece 62 and 3rd sliding piece 63 The first sliding piece 61, the second sliding piece 62, and the third sliding piece 63 are pulled in, and the upper surface of the holder 40 and the upper surface of the first sliding piece 61 and the second sliding piece 62 are on the movable side. It is flush with the upper surface of the template 108. When the molding is completed, the molding material is injected and the next molded product P10 is molded.

The hole in the undercut portion P11 is formed by splitting the sliding pieces and allowing each sliding piece to move in different directions as in the undercut processing mechanism 14 of the molding die 2 of the present embodiment. As in P12, in the undercut portion, the die-cutting direction of the undercut portion is different from that of the undercut portion, and the die-cutting of the molded product having another undercut portion can be realized only by the pushing-out operation of the holder.

The molded product that can be molded in the molding die of the present invention is not limited to the shape shown in the present embodiment that has two holes P12 linearly arranged in the undercut portion P11. .. For example, when there is only one hole P12 in the undercut portion P11 of the molded product P10 on the side of the first sliding piece 61, the second sliding piece 62 is fixedly or integrally configured to the holding piece 50. You may.

When there are three or more holes P12 in different drilling directions, the holes in different drilling directions are separate from the sliding piece (third sliding piece 63) having the pin 35 forming the hollow portion of the undercut portion P11. Sliding pieces corresponding to each of P12 may be provided. For a plurality of holes P12 in the same drilling direction, one sliding piece can correspond to the plurality of holes P12. When the undercut portion P11 does not have a hollow portion, the sliding piece having the pin 35 (third sliding piece 63) may be fixedly or integrally formed with the holding piece 50.

12 to 16 are views showing an example of a molded product that can be molded by the undercut processing mechanism of the present invention and a molding die, respectively, and FIGS. 12 to 16 are front views and side surfaces, respectively. It is a figure, a bottom view, and a perspective view. The undercut processing mechanism of the molding die of the present invention is the undercut portion P21, P41, P51, P61 as shown in FIGS. 12, 14 to 16, and another undercut portion P22, P42, P52. , P53, P62, and the molded products P20, P40, P50, and P60 can also be molded only by the protrusion operation of the holder. The molded product P30 having the undercut portion P31 shown in FIG. 13 can also be molded by an undercut processing mechanism having one sliding piece, such as the undercut processing mechanism 10 of the molding die 1 of the first embodiment. It is possible.

17 is a cross-sectional view of the molding die 3 of the third embodiment of the present invention at the time of mold clamping, FIG. 18 is a cross-sectional view of the molding die 3 of FIG. 17 after opening, and FIG. 19 is a view. 17 is a cross-sectional view of the molded product P10 of the molding die 3 after the ejection operation, and FIG. 20 is a partially disassembled perspective view of the undercut processing mechanism 16 of the molding die 3 of FIG.

The same components as those of the molding die 2 of the second embodiment shown in FIGS. 7 to 11 are designated by the same reference numerals, and the description thereof will be omitted. The molding die 3 of the third embodiment has the same basic configuration as the molding die 2 of the second embodiment, but includes a fixed holder 70 on the outside of the holder 40.

The fixed holder 70 is fixed to the movable side template 108 so as to surround the holder 40. Like the holder 40, the fixed holder 70 is divided into two in consideration of assembling property, but it may be formed of one member or may be formed of three or more members.

In the present embodiment, the holder 40 slides with respect to the fixed holder 70 on the outer peripheral surface and does not slide with respect to the movable side template 108 of the molding die 3, so that the movable side template 108 due to sliding Wear and damage can be avoided.

21 is a cross-sectional view of the molding die 4 of the fourth embodiment of the present invention at the time of mold clamping, FIG. 22 is a cross-sectional view of the molding die 4 of FIG. 21 after opening, and FIG. 23 is a view. 21 is a cross-sectional view of the molded product P10 of the molding die 4 after the ejection operation, and FIG. 24 is a partially disassembled perspective view of the undercut processing mechanism 18 of the molding die 4 of FIG. 21.

The same components as those of the molding die 2 of the second embodiment shown in FIGS. 7 to 11 are designated by the same reference numerals, and the description thereof will be omitted. The molding die 4 of the fourth embodiment has the same basic configuration as the molding die 2 of the second embodiment, but the side surface of the holder 80 is formed in a tapered shape. Correspondingly, the portion of the molding die 4 to which the holder 80 of the movable side mold plate 108 is attached is formed in a tapered shape. The taper functions as an attraction when the holder 80 is pulled into the movable side template 108 during mold clamping, thereby reducing wear and damage to the holder 80 and the movable side template 108.

The undercut processing mechanism, the molding die, and the molded product of the present invention have been described above using the molding dies 1, 2, 3, and 4 of the first to fourth embodiments, but the undercut of the present invention has been described. The processing mechanism, the molding die, and the molded product are not limited to the above-described embodiment, and can be modified and used without changing the gist. For example, the features of the molding dies 1, 2, 3, and 4 of the first to fourth embodiments can be used in combination as long as the configuration is possible.

In the undercut processing mechanism and the molding die of the present invention, the holding piece and the sliding piece are not limited to those formed of one member, and may be composed of a plurality of members. In the case of being composed of the members of the above, for example, they may be joined via bolts, knock pins, or the like, or may be joined without using bolts, knock pins, or the like. This is not limited to the holding piece and the sliding piece, but is the same for each component of the molding die.

Further, in the molding die 1 of the first embodiment, the means for regulating the holder 20 and the sliding piece 21 may be a dovetail groove and a ridge, and in this case, the dovetail groove and the sliding piece 21 are formed in the holder 20. The ridges may be provided, the holder 20 may be provided with ridges, and the sliding piece 21 may be provided with dovetail grooves. Similarly, as the regulating means for the sliding piece 21 and the holding piece 22, the sliding piece 21 may be provided with a protrusion and the holding piece 22 may be provided with a dovetail groove. The same applies to the molding dies 2, 3 and 4 of the second to fourth embodiments.

Further, in the molding die 1 of the first embodiment, the oblique grooves 30 and the ridges 33, and the dovetail grooves 36 and the ridges 38 that engage with each other are rectangular in which the cross-sectional shape of the engaging portion is shown in the figure. The cross section of the engaging portion is not limited, and may be circular, triangular, or the like. Further, in the undercut processing mechanism of the present invention, the regulating means of the holder 20, the sliding piece 21, and the holding piece 22 is not limited to the oblique groove 30, the ridges 33, 38, and the dovetail groove 36, and is, for example, linear. A guide or the like may be used. The same applies to the molding dies 2, 3 and 4 of the second to fourth embodiments.

It is also possible to provide a plurality of undercut processing mechanisms in the molding die of the present invention. That is, according to the undercut processing mechanism and the molding die of the present invention, it is also possible to mold and die-cut a molded product having an undercut portion such as a plurality of cylindrical bosses. If the protruding direction of each undercut portion, that is, the direction in which die-cutting is possible, is different, the corresponding undercut portion can be die-cut in each undercut processing mechanism, and the diagonal groove of the holder, sliding piece, and holding piece. , Dovetail groove, ridge, etc., the inclination angle of the regulating means may be set as appropriate.

Further, in the molding dies 2, 3 and 4 of the second to fourth embodiments, the first sliding piece 61 and the second sliding piece 62 are shown to slide in the left-right direction in the figure. The present invention is not limited to this, and for example, it is naturally possible to configure it so as to slide in the front-back (depth) direction of the figure.

Further, in the undercut processing mechanism and the molding die of the present invention, R chamfering, C chamfering, etc. may be applied to the corners and side edges of each constituent member.

Further, the material of each component used in the undercut processing mechanism and the molding die of the present invention is not limited to a specific material, and is used in a known undercut processing mechanism and the molding die. Any material similar to the material of the member may be used as appropriate. However, for the sliding surface of each component, it is preferable to use a material having good slidability or a material having a surface treatment having good slidability. Note that each sliding surface is not limited to a surface contact, and may be a line contact or a point contact.

Further, the undercut processing mechanism of the present invention can be applied to a molding die that opens and closes horizontally, vertically or in other directions.

Further, the undercut processing mechanism and the molding die of the present invention can be suitably used for mold dies such as die casting dies, mold press molding dies, etc., in addition to injection molding dies.

As described above, the preferred embodiment has been described with reference to the drawings, but those skilled in the art will easily assume various changes and modifications within a trivial range by looking at the present specification. Therefore, such changes and amendments are construed as being within the scope of the invention as defined by the claims.

1, 2, 3, 4 Molds for molding 10, 14, 16, 18 Undercut processing mechanism 20, 40, 70, 80 Holder 21 Sliding piece 22, 50 Holding piece 30, 42 Oblique groove 33, 38, 67 Convex Strips 35 Pins 36, 66, 69 Dovetail groove 41 Horizontal groove 51 First convex strip 52 Second convex strip 53 Third convex strip 61 First sliding piece 62 Second sliding piece 63 Third sliding piece 70 Outer holder P , P10, P20, P30, P40, P50, P60 Molded products P1, P2, P3, P11, P21 Undercut part P31, P41, P51, P61 Undercut part

Claims (10)

An undercut processing mechanism that is attached to a molding die for molding a molded product with an undercut portion and enables the undercut portion protruding in a direction intersecting the die cutting direction of the molded product to be die-cut. There,
A holder for accommodating at least a part of a sliding piece and a holding piece, which is attached to the molding die so as to be movable in the die cutting direction of the molded product.
With the sliding piece that is slidable with respect to the holder and forms the undercut portion,
With the holding piece fixed or integrally formed on the molding die so as to hold the sliding piece slidably.
Equipped with
The feature is that the sliding piece moves in a direction in which the undercut portion can be die-cut by moving the holder in the die-cutting direction of the molded product when the molded product is die-cut. Undercut processing mechanism. The undercut processing mechanism according to claim 1, wherein the sliding piece and the holding piece are arranged side by side in the moving direction of the holder and adjacent to each other. The undercut processing mechanism according to claim 1 or 2, wherein the holder is configured to protrude the molded product when the molded product is ejected. The one according to any one of claims 1 to 3, wherein each of the holder and the holding piece is provided with a regulating means for restricting the moving direction of the sliding piece in a direction in which the undercut portion can be die-cut. Undercut processing mechanism. The restricting means of the holder is provided so that the sliding piece engages with the sliding piece so as to be slidable with respect to the holder in a direction in which the undercut portion can be die-cut.
The restricting means of the holding piece is provided so that the sliding piece is slidably engaged with the holding piece in a direction orthogonal to the direction in which the undercut portion can be die-cut. The undercut processing mechanism according to claim 4, wherein the undercut processing mechanism is provided. The claim is characterized in that the sliding piece includes a molding member for forming the hollow portion or the space portion of the undercut portion so that the molded product having the hollow portion or the space portion in the undercut portion can be molded. Item 6. The undercut processing mechanism according to any one of Items 1 to 5. The sliding piece is composed of a plurality of divided sliding pieces.
A claim characterized in that at least two of the plurality of sliding pieces are configured to move in a direction different from the moving direction of the holder and in a direction different from each other when the holder is moved. Item 6. The undercut processing mechanism according to any one of Items 1 to 6. The invention according to any one of claims 1 to 7, further comprising an outer holder that is fixed to the molding die and slides the holder in order to prevent wear of the molding die. Undercut processing mechanism. The holder is characterized in that a part or all of the outer peripheral surface serving as a sliding surface and / or the outer peripheral surface is formed in a tapered shape in order to prevent wear of the molding die. The undercut processing mechanism according to any one of 8 to 8. A molding die comprising the undercut processing mechanism according to any one of claims 1 to 9.

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