JP5798776B2 - Mold equipment - Google Patents

Description

  The present invention relates to a mold apparatus.

  One of mass production techniques using a mold apparatus is die casting. In die casting, a cavity is provided between a pair of molds consisting of a fixed mold and a movable mold. After the molten metal injected into the cavity is solidified, the cast product is formed by separating both molds.

  In the case where the cavity is constituted by only a pair of molds, a portion that is convex or concave in the direction intersecting the mold opening direction in the outer shape of the cast product can be an obstacle to mold opening or mold release operation. For this reason, when the cast product is formed by die casting, the shape of the cast product is likely to be restricted. Moreover, about the part which becomes the said obstruction (henceforth an undercut part), it can become a factor which makes mass production of a cast product difficult.

  In order to cope with these problems, for example, in the mold apparatus shown in Patent Document 1, a portion corresponding to the undercut portion of the cavity is configured by a slide core provided separately from the fixed mold and the movable mold. Yes. When the fixed core and the movable mold are released, the slide core is retracted in a direction intersecting the mold opening direction, so that it is possible to avoid catching between the undercut portion and the movable mold. Thereby, the restriction of the shape on the mold structure generated in the cast product can be suppressed, and mass production of the cast product having the undercut portion can be realized.

JP 2007-144755 A

  When the above-described slide core is employed to form the undercut portion, it is necessary to secure a retract path for the slide core at the time of mold release. For this reason, when there exists a part which prevents retraction | saving of a slide core in a fixed mold | type, a movable mold | type, or a casting product, application of a slide core becomes difficult. In this case, additional processing such as cutting for forming an undercut portion after molding is required, which may be an obstacle to shortening the time required for manufacturing and reducing manufacturing cost.

  This invention is made | formed in view of the said situation, and it aims at provision of the metal mold | die apparatus which can suppress the restrictions on the shaping | molding of the undercut part resulting from a product shape, and can improve manufacturing efficiency suitably. .

  The present invention employs the following means in order to solve the above problems.

  That is, in the first invention, the first mold (movable mold 12) and the second mold (fixed mold 11) are provided, and the first mold and the second mold are combined to form a cavity (cavity). C) In the mold apparatus in which the first mold is formed, the molded product (cast product 100) molded in the cavity is separated from the first mold and the second mold. An extrusion mechanism (extrusion base portion 71 and the like) for extruding from the second mold side to the second mold side, and the first mold includes a plurality of mold components (movable matrix 41, center pin) that form part of the cavity. 61, an extrusion sleeve 81), and at least one of the mold components is provided so as to be displaceable in a direction crossing an extrusion direction of the molded product by the extrusion mechanism, Form cut (annular protrusion 105) An extrusion operation of the extrusion mechanism in an undercut forming portion (extrusion sleeve 81) in a state in which the molded product is extruded from the initial position engaged with the first mold to the predetermined extrusion position by the extrusion mechanism. And guiding portions (tapered portions 66 and 86) for guiding the undercut forming portion in the intersecting direction to separate the undercut forming portion from the undercut portion.

  According to the first invention, the undercut forming portion is separated from the undercut portion by being guided in a direction intersecting the extrusion direction based on the extrusion operation of the molded product. By making use of the original function of the mold device to extrude the molded product from the mold, the undercut forming part is separated from the undercut part (that is, by retreating), so that the structure of the mold apparatus is complicated and large. It is possible to form the undercut portion while suppressing the deformation.

  In addition, since the undercut forming portion can be guided based on the extrusion operation of the molded product, it is not necessary to separately provide a step only for performing the guidance in the step of taking out the product from the mold apparatus. Thereby, the fall of manufacturing efficiency can be suppressed.

  After the mold apparatus is in the mold open state, the undercut forming portion is guided in the intersecting direction in a state where the molded product is extruded by the extrusion mechanism. Thus, by guiding the undercut forming portion after extruding the molded product to some extent, it is possible to suppress the displacement of the undercut forming portion from being hindered by the mold or the molded product. As a result, it is possible to suppress the restriction on molding of the undercut portion due to the product shape, and to suitably improve the manufacturing efficiency.

  In addition, for example, when it is assumed that the molded product is deformed by forcibly extruding the molded product and the molded product is taken out, the shape and size of the undercut part, the material of the molded product, etc. are likely to be limited, so it is practical. Not preferable. In this regard, in the present invention, the above-described limitation can be suppressed by adopting a configuration in which the undercut forming portion is retracted.

  In 2nd invention, the said guide part complete | finishes the induction | guidance | derivation of the said undercut formation part, while the extrusion of the said molded article is performed by the said extrusion mechanism.

  According to the second aspect of the invention, the induction of the undercut forming portion is completed within the period during which the molded product is extruded. As a result, it is possible to suppress an increase in the period required for taking out the molded product from the mold apparatus, and to secure manufacturing efficiency.

  In a third aspect of the invention, the undercut forming portion has a portion that comes into contact with the molded product waiting at the initial position from the front side in the extrusion direction, and the extrusion mechanism includes the undercut forming portion. By displacing in the extrusion direction, the molded product is extruded.

  According to the third aspect of the present invention, when the molded product is extruded by the undercut forming portion, the undercut forming portion and the molded product are integrally displaced during extrusion. Thereby, generation | occurrence | production of the disadvantage that extrusion of a molded article is prevented by the undercut formation part can be avoided.

  In addition, by applying both the extrusion function and the undercut avoidance function to the undercut forming part, a complicated structure such as a link mechanism is not necessary, and the structure for realizing the operation of the undercut forming part. Can contribute to simplification.

  In 4th invention, the said metal mold structure of the said 1st metal mold | die other than the said undercut formation part is a main body part (cylinder part 101,102) other than the said undercut part in the said molded article. ), And the main body forming portion is in contact with the undercut forming portion to restrict displacement of the undercut forming portion in the intersecting direction. A main body side abutting portion (inner peripheral surface 17 of the insertion portion 16) is formed, and the undercut forming portion abuts the main body side abutting portion at an initial position, and the undercut forming portion includes An undercut-side contact portion (outer large-diameter portion 88 of the extrusion sleeve 81) is formed so as to avoid contact with the main body-side contact portion when displaced from the initial position to a predetermined molded product extrusion position. And said When the undercut forming part is displaced to the predetermined molded product extrusion position, the main body side contact part and the undercut side contact part are displaced in the crossing direction by separating in the extrusion direction. The restriction is released, and the undercut forming part is allowed to be guided by the guide part.

  In the configuration in which the undercut forming portion is guided, it is difficult to determine the position of the undercut forming portion at the time of molding, so that the molding accuracy of the molded product (specifically, the undercut portion) can be lowered. Here, in the present invention, when the undercut forming portion is disposed at the initial position, the main body side contact portion and the undercut side contact portion are brought into contact with each other, so that the undercut formation portion is guided. Displacement is regulated. Thereby, it is possible to suppress a decrease in molding accuracy.

  On the other hand, when the molded product is removed, the undercut forming portion is displaced in the extrusion direction, whereby both contact portions are separated in the extrusion direction, and the displacement restriction in the induction direction is released. For this reason, even if it suppresses the fall of shaping | molding precision, it is avoided that it becomes difficult to shape | mold an undercut part resulting from it.

  The “initial position” of the undercut forming portion indicates, for example, a position where the undercut portion is molded (a position where the undercut portion is engaged), and the “predetermined molded product extrusion position” indicates, for example, a predetermined molded product. The position of the undercut formation part at the time of extrusion to the said predetermined | prescribed extrusion position is shown.

  In 5th invention, the said main body formation part is formed in the same direction as the said extrusion direction, and the accommodating part (insertion part 16) which accommodates the said undercut formation part is formed, The said guidance part is said main body formation An inclining portion for guidance that is provided on one of a portion facing the undercut forming portion in the portion and a portion facing the main body forming portion in the undercut forming portion and is inclined toward the extrusion direction ( One of the taper portions 66, 86), the other of the portion facing the undercut forming portion in the main body forming portion and the portion facing the main body forming portion in the undercut forming portion, A guide abutting portion (the other of the taper portions 66 and 86) that abuts on the guiding inclined portion due to the displacement of the undercut forming portion in the extrusion direction. The forming part is configured such that the part forming the cavity in the undercut forming part protrudes from the accommodating part by reaching the predetermined molded product extrusion position, The guiding contact portion is formed so as to contact the guiding inclined portion when the undercut forming portion reaches the predetermined molded product pushing position by the extrusion or thereafter.

  According to the fifth aspect, the guiding inclined portion and the guiding contact portion are brought into contact with each other by displacing the undercut forming portion in the pushing direction. And the undercut formation part is induced | guided | derived to the said crossing direction along the inclination of the inclination part for guidance by the further displacement to the extrusion direction. Thereby, it can contribute to simplification of the structure concerning guidance.

  In the configuration in which the undercut forming portion is housed in the housing portion, the housing portion itself (main body forming portion) can be a factor that prevents the undercut forming portion from being guided. Therefore, if the above-described guidance is performed in a state in which the portion forming the cavity in the undercut forming portion protrudes from the housing portion, at least the portion forming the cavity in the undercut forming portion and the housing It is possible to make it difficult to cause inconvenience that the part can be used.

  In the sixth invention, the main body forming portion has a shaft portion (center pin 61) extending in the same direction as the housing portion and housed in the housing portion, and the undercut forming portion is an outer surface of the shaft portion. And an inner surface of the housing portion, and the undercut forming portion extends in the same direction as the shaft portion and forms a cylindrical body surrounding the shaft portion, and the undercut forming portion is In the state of being arranged at the initial position of the undercut forming part, a part of the cavity is formed between the undercut forming part and the shaft part, and one of the guiding inclined part and the guiding contact part Is provided at the shaft portion, and the other of the guide inclined portion and the guide contact portion is provided at each of the undercut forming portions, and by the extrusion, the undercut forming portion is brought into the predetermined molded product extrusion position. When each of the undercut forming portions is guided by the guide portion at or after that time, the undercut forming portions are displaced in the radial direction of the shaft portion, so that the inner diameter of the cylindrical body is the molded product. Is enlarged to allow the passage of

  According to the sixth aspect of the invention, in the state where the undercut forming portion is displaced in the extrusion direction and the portion forming the cavity in the undercut forming portion protrudes from the housing portion, A cylindrical portion (specifically, a portion including the undercut portion) formed between the undercut forming portion and the undercut forming portion is caught. Here, when each undercut forming portion is displaced in the radial direction of the shaft portion and the inner diameter of the cylindrical body is enlarged, the above-mentioned catch is released. Thereby, facilitation of taking out the molded product is realized. According to the configuration shown in the present invention, for example, when an annular protrusion (corresponding to an undercut portion) such as a flange is set at the tip of a cylindrical portion of a molded product, the annular protrusion can be easily formed. .

  For example, the undercut forming portion may be guided at the same time. As a result, it is possible to suppress the time required for inducing the undercut portion and to suppress a decrease in manufacturing efficiency.

  In 7th invention, the said accommodating part comprises the round hole shape extended in the same direction as the said extrusion direction, the said axial part is arrange | positioned coaxially with the center axis line, and the said cylindrical body is substantially cylindrical shape. And each undercut forming portion is at least in an initial position and has an outer surface abutting against an inner surface of the housing portion, and an inner surface of the undercut forming portion is on the outer surface of the shaft portion. It is formed so as to abut.

  According to the seventh aspect of the invention, when a cylindrical body is constituted by a plurality of undercut forming portions, the molding accuracy can change due to variations in the positional relationship and posture between the undercut forming portions. Here, according to the present invention, at least in the state of being arranged at the initial position, each of the undercut forming portions is sandwiched between the inner surface of the housing portion and the outer surface of the shaft portion, thereby stabilizing the positional relationship and posture. It is possible. Thereby, the fall of shaping | molding precision can be suppressed.

  In an eighth aspect of the invention, the housing portion, the shaft portion, and each undercut forming portion are arranged such that the outer surface of the undercut forming portion is in the state until the undercut forming portion reaches the predetermined molded product extrusion position. It is formed so as to be in contact with the inner surface of the housing portion and maintain the state in which the inner surface of the undercut forming portion is in contact with the outer surface of the shaft portion.

  As shown in the seventh invention, when a cylindrical body is formed by a plurality of undercut forming portions, the displacement of each undercut forming portion in the guiding direction is increased by increasing the number of undercut forming portions. The amount can be reduced. Thereby, as above-mentioned, it can contribute to shortening of the period which takes out of a molded article. However, when the undercut forming portion has a function of extruding the molded product, deformation of the undercut forming portion or the like may occur due to a reaction force when the molded product is extruded. This is not preferable because it causes a decrease in molding accuracy.

  Here, as shown in the present invention, at least until the predetermined molded product extrusion position is reached, by maintaining the state sandwiched between the outer surface of the shaft portion and the inner surface of the housing portion, It is possible to suppress the positional relationship from changing, and to suppress an increase in the load generated in the specific undercut forming portion. That is, it is possible to easily disperse the load generated in the undercut forming portion, and it is possible to suppress the inconvenience such as the above-described deformation.

  In the ninth invention, on the outer peripheral surface of the cylindrical body, an outer large-diameter portion (outer large-diameter portion 88) as the undercut side contact portion, and the second gold against the outer large-diameter portion. An outer small-diameter portion (outer small-diameter portion 87) that is located on the opposite side of the mold and has an outer diameter smaller than that of the outer large-diameter portion is formed, and the cylindrical body is an initial portion of the cylindrical body. In the state of being disposed at the position, the outer large-diameter portion abuts the inner surface of the housing portion, the outer small-diameter portion and the inner surface of the housing portion are opposed to each other with a gap therebetween, and the cylindrical body is The outer large-diameter portion protrudes from the housing portion when the predetermined molded product push-out position is reached, so that a gap between the outer small-diameter portion and the inner surface of the housing portion forms each undercut at the time of induction. It functions as the operation area of the part.

  According to the ninth aspect, when the cylindrical body (undercut forming portion) is displaced in the extrusion direction and reaches a predetermined molded product extrusion position, the outer large-diameter portion that has been in contact with the inner surface of the housing portion until then. Protrudes from the accommodating portion and is separated from the inner surface. Here, the outer small-diameter portion of the cylindrical body is configured such that a predetermined gap is secured between the outer small-diameter portion and the inner surface of the housing portion, and this gap becomes an operation region of each undercut forming portion. Thereby, it becomes possible to guide each undercut forming portion in the intersecting direction.

  In a tenth aspect of the invention, the inner peripheral surface (inner peripheral surface 82) of the undercut forming portion is provided with an inner small diameter portion (small diameter portion 84) and the same small diameter provided closer to the second mold than the small diameter portion. An inner large-diameter portion (large-diameter portion 85) whose inner diameter is set larger than the portion, and an inner connecting portion (taper portion 86) that connects the inner small-diameter portion and the inner large-diameter portion are formed, and the outer periphery of the shaft portion On the surface (outer peripheral surface 62), when the undercut forming portion is disposed at least at the initial position of the undercut forming portion, a shaft side small diameter portion (small diameter portion 64) that contacts the inner small diameter portion; When the undercut forming portion is disposed at least at the initial position of the undercut forming portion, a shaft-side large-diameter portion (large-diameter portion 65) that contacts the inner large-diameter portion, the shaft-side small-diameter portion, Shaft side connecting part (tapered part 66) connecting the shaft side large diameter part And any one of the inner connecting portion and the shaft side connecting portion is the guiding inclined portion, the other is the guiding contact portion, and the undercut forming portion is In a state where the guide portion is displaced to the guide position, the inner small diameter portion and the shaft side large diameter portion abut.

  According to the tenth aspect of the invention, it is possible to expect improvement in the positional accuracy of the undercut forming portion because the small diameter portions abut each other and the large diameter portions abut at the time of molding. When the undercut forming portion is displaced in the extrusion direction by the extrusion mechanism, the guiding inclined portion and the guiding contact portion are brought into contact with each other, whereby the large diameter portions are separated from each other and the small diameter portions are separated from each other. In such a state, although the guiding function is exhibited, the posture of the undercut forming portion tends to become unstable. Then, in the state which reached | attained the guidance position, the attitude | position of an undercut formation part can be stabilized because it will be in the state which the inner side small diameter part and the axial side large diameter part contact | abutted. Thereby, it can suppress that the taking-out operation | work of a molded article becomes difficult. In addition, the margin required for the gap between the undercut portion and the undercut forming portion when the molded product is taken out can be reduced, and it is possible to avoid an unnecessary increase in the amount of displacement during induction.

  In an eleventh aspect of the invention, the main body forming portion is formed by the guide portion when the undercut forming portion reaches the predetermined molded product extrusion position and the molded product is extruded to the predetermined extrusion position. The undercut forming portion is formed so as to secure an operation space of the undercut forming portion in a portion serving as a guide destination of the undercut forming portion.

  According to the eleventh aspect of the invention, undercut formation is performed in a situation where the first mold and the second mold are separated from each other and the molded product is extruded from the first mold to the predetermined molded product extrusion position. A space allowing the displacement of the parts in the intersecting direction is secured. Thereby, the induction | guidance | derivation function of an undercut formation part can be ensured.

  In the twelfth invention, the first mold (movable mold 12) and the second mold (fixed mold 11) are provided, and the cavity (cavity C) is obtained by combining the first mold and the second mold. In the mold apparatus in which the first mold and the second mold are separated, the molded product (cast product 100) molded in the cavity is separated from the first mold. An extrusion mechanism (extrusion base portion 71 and the like) for extruding to the second mold side is provided, and the first mold includes an inner member (center pins 61 and 61Z) and an outer member (extrusion sleeve 81 and movable sleeve 81Z). And a core unit (core unit 18) that forms at least a part of the cavity by both of these members is provided, and the first mold and the second mold are separated from each other in the mold open state. The outer member and the inner part Drive mechanism (drive part, extrusion base part 71, tension base part 71, etc.) for displacing one of the undercut formation parts corresponding to the undercut part in a direction parallel to the die cutting direction of the molded product And by guiding one of the outer member and the inner member having the undercut forming portion in a direction intersecting with the central axis of the core unit based on the displacement by the driving mechanism, from the undercut portion. Means for separating the one side.

  According to the twelfth invention, one of the outer member and the inner member having the undercut forming portion corresponding to the undercut portion is molded in the mold open state where the first die and the second die are separated. Displacement in a direction parallel to the die-cutting direction of the product and a configuration in which the one is displaced in a direction intersecting the central axis of the core unit based on the displacement, thereby forming the undercut portion in the mold or molding It is possible to suppress obstruction by the product.

(A) Sectional drawing of the die-casting apparatus in 1st Embodiment, (b) Sectional drawing of the die-casting apparatus which shows the open state. (A) Top view of fixed mold, (b) Plan view of movable mold. It is a figure which expands and shows the X part of Fig.1 (a). 5A is a perspective view of the core unit, FIG. 5B is an exploded perspective view of the core unit, and FIG. 4C is a view as viewed from the arrow Y in FIG. It is the schematic which shows a motion of a product extrusion mechanism. It is the schematic which shows operation | movement of a die-cast apparatus. It is the schematic which shows operation | movement of a die-cast apparatus. It is the schematic which shows operation | movement of a die-cast apparatus. It is the schematic which shows operation | movement of a die-cast apparatus. It is the schematic for demonstrating the restrictions of the type | mold structure based on the shape of a molded article. It is sectional drawing which shows the die-casting apparatus in 2nd Embodiment.

<First Embodiment>
Hereinafter, the mold apparatus according to the first embodiment will be described with reference to FIGS. 1 and 2. In the present embodiment, it is assumed that the mold apparatus is embodied as a die casting apparatus having a fixed mold and a movable mold, and an aluminum casting product is manufactured by the die casting apparatus. FIG. 1A is a cross-sectional view showing a die casting apparatus in a closed state in which a fixed mold and a movable mold are combined, and FIG. 1B is a mold open state in which the fixed mold and the movable mold are separated. FIG. 2A is a plan view of a fixed mold, and FIG. 2B is a plan view of a movable mold. Each plan view shown in FIG. 2 is a view of the fixed mold and the movable mold as viewed from opposite sides. In FIG. 2A, for convenience, the cross-sectional position of FIG. 1 is indicated by the AA line, but the cutting target is both a fixed mold and a movable mold.

  As shown in FIG. 1 (a), in the die casting apparatus 10, a fixed mold 11 and a movable mold 12 are integrally combined to form a mold closed state, thereby forming a casting space into which molten metal is poured. A cavity C is formed.

  The fixed die 11 has a fixed mother die 21 having a block shape, and this fixed mother die 21 is attached to a fixed stationary platen 13 provided in the die casting apparatus 10.

  A receiving groove 25 for nesting is formed in a portion of the fixed mother die 21 facing the movable mold 12, and the fixed nesting 31 is fixed in a state in which the receiving groove 25 is fitted. The fixed-side insert 31 is made of a metal material that is superior in heat resistance and wear resistance as compared with the fixed matrix 21, and a part of the cavity C is partitioned by the fixed-side insert 31. By providing the fixed side nest 31 separately from the fixed mother die 21, the fixed side nest 31 can be replaced alone.

  The movable mold 12 includes a movable mother mold 41 having a block shape. The movable mother die 41 has a substantially rectangular parallelepiped main body portion 42 and a plurality of spacer portions 43 that protrude from the main body portion 42 to the side opposite to the fixed mold 11. A mounting plate 44 is fixed to the distal end portions of the spacer portions 43. The mounting plate 44 is attached to a movable fixed platen 14 provided in the die casting apparatus 10, and the movable die 12 is operated based on the operation of the fixed platen 14 (movement of both molds 11, 12 in the juxtaposed direction). Moves to the side approaching the fixed mold 11 and the side moving away from the fixed mold 11 (see FIG. 1B).

  Guide pins 27 (see FIG. 2) that protrude toward the movable mold 12 are provided at the four corners of the fixed mold 21, and the guide pins 27 are provided on the main body 42 of the movable mold 41. It is inserted through the hole 45 (see FIG. 2). The guide pin 27 and the guide hole 45 have a function of defining the relative movement direction between the fixed mold 11 and the movable mold 12. Specifically, when the movable mold 12 moves away from the fixed mold 11, the die casting apparatus 10 enters a mold open state (release state), and after the mold open state, the movable mold 12 is fixed. The die casting apparatus 10 is switched to the mold closed state by moving toward the mold 11.

  A portion of the movable base 41 facing the fixed side insert 31 of the fixed mold 11 is formed with a storage groove 46 for insertion, and the movable side that forms a pair with the fixed side insert 31 in the storage groove 46. The nest 51 is fixed in a fitted state. The surface of the fixed side insert 31 facing the movable mold 12 side (hereinafter referred to as the mating surface 32) is formed with a raised portion 33 that protrudes toward the movable mold 12 side. On the surface facing the mold 11 side (hereinafter referred to as the mating surface 52), an accommodation recess 53 for accommodating the raised portion 33 of the fixed side insert 31 is formed.

  In the mold closed state, the peripheral portion of the accommodating recess 53 on the mating surface 52 of the movable side insert 51 and the peripheral portion of the raised portion 33 on the mating surface 32 of the fixed side insert 31 are in contact with each other. Both the nests 31 and 51 are formed so that the raised portion 33 and the accommodating recess 53 face each other with a gap in a state where the mating surfaces 32 and 52 are in contact with each other as described above. The gap formed in this way constitutes most of the cavity C.

  The fixed mother die 21 is provided with a gate 28 for casting a molten aluminum into the cavity C, and the movable mold 12 has a molten metal flow passage (casting passage and runner) connected from the gate 28 to the cavity C. An overflow portion is provided for receiving the molten metal overflowing from the cavity C. Each mold 11 and 12 is formed with a medium flow path of a cooling medium that promotes solidification of the molten metal injected into the cavity C.

  One of the product extrusion mechanisms 70 (see FIG. 2) used when the cast product is taken out from the die casting apparatus 10 in the space secured by the spacer portion 43, that is, the space sandwiched between the main body portion 42 and the mounting plate 44. Department is housed. Hereinafter, the product extrusion mechanism 70 and the related configuration will be described with reference to FIGS. 1, 3, and 4. 3 is a partially enlarged view showing a portion X in FIG. 1, FIG. 4 (a) is a perspective view showing a main configuration of the product extrusion mechanism 70, and FIG. 4 (b) is an exploded view showing a main configuration of the product extrusion mechanism 70. A perspective view and FIG.4 (c) are Y arrow line views of Fig.4 (a).

  As shown in FIG. 3, the movable side insert 51 is formed with a through hole 54 extending in the same direction as the moving direction of the movable mold 12 (the direction in which both molds 11 and 12 are arranged side by side). One end of the through hole 54 communicates with the bottom of the housing recess 53. That is, an opening 55 is formed at the bottom as an entrance to the through hole 54.

The other end of the through hole 54 communicates with a portion facing the bottom of the receiving groove 46, and a communication hole 47 communicating with the through hole 54 is formed in the movable mother die 41. The through hole 54 and the communication hole 47 constitute a round hole-shaped insertion portion 16 formed so that the hole diameter is substantially constant.
An extrusion sleeve 81 constituting the product pushing mechanism 70 can be moved in the insertion portion 16 in the same direction as the central axis CL of the insertion portion 16 (the direction in which both molds 11 and 12 are arranged in parallel). It is inserted so that it becomes.

  The push-out sleeve 81 has a substantially cylindrical shape extending in the same direction as the insertion portion 16, and a function of partitioning the cavity C together with the housing recess 53 and the raised portion 33 is given to the tip portion.

  A center pin 61 as a core is inserted into the extrusion sleeve 81. The center pin 61 has a cylindrical shaft portion 61a, and is formed such that one end portion (specifically, the end surface 63) of the shaft portion 61a is positioned on substantially the same plane as the opening 55. That is, the end surface 63 of the shaft portion 61 a is provided with a function of partitioning and forming the cavity C together with the distal end portion of the extrusion sleeve 81.

  In view of the fact that the end surface 63 of the center pin 61 and the distal end portion of the extrusion sleeve 81 are provided with a function of forming the cavity C together with the receiving recess 53 and the raised portion 33, the center pin 61 and the extrusion sleeve 81 are connected to the core unit 18. It is also possible to call it.

  The other end of the center pin 61 is formed so as to protrude from the main body 42 to the mounting plate 44 side. A disc-shaped fixed base portion 61b is provided at the other end portion, and the fixed base portion 61b is attached to the mounting plate 44 so that the center pin 61 and the movable mother die 41 are integrated. Yes.

  The extrusion sleeve 81 is located in a space where approximately half of the extrusion sleeve 81 on the cavity C side is sandwiched between the outer peripheral surface 62 of the center pin 61 (specifically, the shaft portion 61a) and the inner peripheral surface 17 of the insertion portion 16. Arranged to do so. In other words, the outer peripheral surface 62 of the center pin 61 and the inner peripheral surface 17 of the insertion portion 16 are provided with a function of restricting the displacement of the extrusion sleeve 81 in the direction intersecting the central axis CL.

  A substantially plate-like extrusion base 71 that is orthogonal to the central axis CL is attached to the shaft 61 a of the center pin 61. Specifically, a through-hole 72 that penetrates in the thickness direction of the extrusion base portion 71 is formed in the extrusion base portion 71, and the center pin 61 is inserted through the through-hole 72. The through hole 72 has a portion whose hole diameter is equal to the outer diameter of the center pin 61, and the center pin 61 and the extrusion base portion 71 are in contact with each other.

  The extrusion base portion 71 is movable in the same direction as the center axis CL along the center pin 61, and the movement range is defined by the fixed base portion 61 b and the main body portion 42 of the center pin 61.

  In the die casting apparatus 10 shown in the present embodiment, in addition to the center pin 61, other means for defining the moving direction of the extrusion base portion 71 to be the same direction as the central axis CL of the insertion portion 16 is used in combination. Yes. Specifically, as shown in FIG. 1, return pins 75 extending toward the main body 42 are provided at the four corners of the extrusion base 71, and the tip portions of the return pins 75 are guides formed on the main body 42. The hole 48 is inserted. When the extrusion base portion 71 reciprocates, the return pin 75 slides in the guide hole 48 to prevent the extrusion base portion 71 from being inclined with respect to the central axis CL.

  A coil spring 76 is attached to the return pin 75 as an urging means for urging the pushing base portion 71, and the pushing base portion 71 is closest to the mounting plate 44 by the urging force of the coil spring 76 (hereinafter referred to as an initial stage). (Referred to as position). Hereinafter, the state where the extrusion base unit 71 is waiting at the initial position is referred to as an initial state.

  Opening portions 44a that are open on both sides in the thickness direction of the mounting plate 44 are formed in a portion of the mounting plate 44 that faces the extrusion base portion 71. Through these openings 44a, extrusion of a hydraulic cylinder device or the like is performed. An extrusion rod R provided in the drive unit is in contact with the extrusion base 71. When the extrusion rod R pushes the extrusion base portion 71 toward the fixed mold 11, the extrusion base portion 71 moves toward the main body portion 42 against the urging force of the coil spring 76. Following the movement of the extrusion base 71, the extrusion sleeve 81 moves in the same direction. As a result, the extrusion sleeve 81 protrudes into the housing recess 53 (cavity C), and the cast product 100 is lifted from the mating surface 52 and pushed out of the housing recess 53.

  When extrusion of the cast product 100 is completed and pressurization by the extrusion driving unit is completed, the extrusion rod R moves backward. Accordingly, the pushing sleeve 81 and the pushing base portion 71 are returned to the initial positions by the biasing force of the coil spring 76.

  As shown in FIG. 1B, the cast product 100 formed by the die casting apparatus 10 has a stepped cylindrical shape that extends in the direction in which the molds 11 and 12 are combined. More specifically, a fixed-side cylinder portion 101 that is set to have a relatively large diameter and is positioned on the fixed mold 11 side, a movable-side cylinder portion 102 that is set to have a relatively small diameter and is positioned on the movable mold 12 side, It has a connecting portion 103 that connects these tube portions 101 and 102. Among these components, the fixed-side cylinder portion 101 and the connecting portion 103 are formed by the molten metal flowing between the raised portion 33 and the accommodation recess 53 solidifying. In the state in which the joint portion 103 is formed in this way, the tip of the extrusion sleeve 81 is in contact with the joint portion 103, and when the extrusion sleeve 81 moves to the extrusion position as described above, the joint portion 103 Becomes an object to be extruded by the extrusion sleeve 81.

  A concave portion 91 is formed at the distal end portion of the extrusion sleeve 81 so that a gap constituting a part of the cavity C is formed between the distal end portion of the center pin 61. The concave portion 91 is connected to a space formed between the raised portion 33 and the accommodating concave portion 53, and the movable side cylindrical portion 102 is formed when the molten metal flowing into the concave portion 91 is solidified.

  An annular protrusion that protrudes in the direction orthogonal to the combination direction of the molds 11 and 12 (radial direction of the central axis CL of the insertion portion 16) at the end of the movable side tube portion 102 opposite to the connecting portion 103. 105 is formed. The annular protrusion 105 is an undercut portion in the die casting apparatus 10.

  The recess 91 is provided with an undercut forming groove 92 for forming the annular protrusion 105. The undercut forming groove 92 is recessed in the radial direction of the central axis CL, and the molten metal injected into the undercut forming groove 92 is solidified to form the annular protrusion 105.

  In the state where the annular protrusion 105 is formed in this way, even if the extruded sleeve 81 is simply moved in the direction of the central axis CL and the cast product 100 is extruded, the annular protrusion 105 of the cast product 100 is undercut. The cast product 100 does not come off from the extruded sleeve 81 because it remains fitted in the groove 92. Therefore, in the present embodiment, a configuration is adopted in which the fitting is avoided based on the displacement of the extrusion sleeve 81 when the cast product 100 is extruded.

  As already described, the extrusion sleeve 81 has a substantially cylindrical shape extending in the same direction as the central axis CL (see FIG. 4A), and as shown in FIG. 3, what is the side forming the cavity C? A flange portion 95 protruding in the radial direction of the central axis CL is provided at the opposite end. The flange portion 95 is fitted in a fitting portion 73 formed on the extrusion base portion 71, and dropping from the extrusion base portion 71 is restricted. That is, one end side of the extrusion sleeve 81 is held by the mounting plate 44 via the extrusion base portion 71 and the like, and the other end side is held by the movable side insert 51.

  As shown in FIGS. 4A and 4B, the extrusion sleeve 81 is constituted by four divided pieces 81a to 81d arranged so as to surround the shaft portion 61a of the center pin 61, and each of these divided pieces. As a whole, 81a to 81d are formed in a substantially cylindrical shape by being combined so as to be in contact with other adjacent divided pieces.

  An inner peripheral surface 82 of the extrusion sleeve 81 includes a small diameter portion 84 provided on the proximal end side of the extrusion sleeve 81, a large diameter portion 85 provided on the distal end side and having an inner diameter set larger than the small diameter portion 84, and The taper part 86 which connects the small diameter part 84 and the large diameter part 85 is comprised, and has comprised the level | step difference shape as a whole.

  On the other hand, the outer peripheral surface 62 of the center pin 61 has a small diameter portion 64 provided on the proximal end side of the center pin 61 and a large diameter provided on the distal end side and having a larger outer diameter than the small diameter portion 64. It is comprised by the part 65 and the taper part 66 which connects these small diameter parts 64 and the large diameter part 65, and has comprised the level | step difference shape as a whole.

  The outer diameter dimension of the small diameter portion 64 of the center pin 61 is the same as the inner diameter dimension of the small diameter portion 84 of the extrusion sleeve 81, and the small diameter portions 64 and 84 are in contact with each other. Further, the outer diameter of the large diameter portion 65 of the center pin 61 and the inner diameter of the large diameter portion 85 of the extrusion sleeve 81 are the same, and the large diameter portions 65 and 85 are in contact with each other. On the other hand, the taper portion 66 of the center pin 61 and the taper portion 86 of the extrusion sleeve 81 face each other with a gap formed between the center pin 61 and the extrusion sleeve 81, and the taper portions 66 and 86 are in contact with each other. It has been avoided.

  By securing the contact portion in this way, the positional deviation between the center pin 61 and the extrusion sleeve 81 is suppressed, and the dimensional accuracy of the cast product (specifically, the portion around the undercut portion) is improved. Yes.

  The outer peripheral surface 83 of the extrusion sleeve 81 is stepped like the inner peripheral surface 82. Specifically, a small diameter portion 87 provided on the proximal end side of the extrusion sleeve 81, a large diameter portion 88 provided on the distal end side (specifically, a part including the distal end portion) of the extrusion sleeve 81, the small diameter portion 87, and The taper part 89 which connects the large diameter part 88 is comprised. On the other hand, the inner diameter of the insertion portion 16 is substantially constant throughout the entire area. Specifically, the outer diameter dimension of the large diameter portion 88 and the inner diameter dimension of the insertion portion 16 are the same. Thereby, the outer peripheral surface 83 of the extrusion sleeve 81 and the inner peripheral surface 17 of the insertion portion 16 are in contact with each other at a part on the cavity C side.

  That is, in the state where the push sleeve 81 is disposed at the initial position, the push sleeve 81 abuts both the inner peripheral surface 17 of the insertion portion 16 and the outer peripheral surface 83 of the center pin 61, whereby the center axis CL is displaced in the radial direction. Is hindered.

  The taper part 89 of the extrusion sleeve 81 is disposed so as to be closer to the cavity C (opening 55) than the taper part 86. The distance dimension between the taper part 86 and the taper part 66 is set to be larger than the allowance between the large diameter part 85 and the insertion part 16 (inner peripheral surface 17) in the central axis CL direction. For this reason, when the extrusion sleeve 81 moves to the cavity C side, the contact between the large-diameter portion 88 of the extrusion sleeve 81 and the insertion portion 16 is first released, so that the taper portions 66 and 86 are in contact with each other. Contact is allowed.

  Here, with reference to FIG. 5, operation | movement of the extrusion sleeve 81 is demonstrated. FIG. 5 is a schematic view showing the operation of the extrusion sleeve 81.

  When the pushing sleeve 81 is displaced following the movement of the pushing base portion 71 in the pushing direction, the pushing sleeve 81 has its outer circumferential surface 83 (specifically, the large diameter portion 88) abutted against the inner circumferential surface 17 of the insertion portion 16. Displaces while maintaining contact. At this time, the inner large diameter portion 85 of the push sleeve 81 is maintained while being in contact with the large diameter portion 65 of the center pin 61, and the inner small diameter portion 84 of the push sleeve 81 is in contact with the small diameter portion 64 of the center pin 61. Maintained. In this way, by setting a plurality of contact locations and securing the interval between the contact locations, deformation of the extrusion sleeve 81 due to the reaction force generated when the cast product 100 is pushed is suppressed.

  Due to such displacement, the protruding amount of the extrusion sleeve 81 from the recess 91 gradually increases, and the entire large diameter portion 88 of the extrusion sleeve 81 protrudes from the opening 55 of the insertion portion 16 (see FIG. 5B). Thereby, the gap existing between the outer small diameter portion 87 of the extrusion sleeve 81 and the inner peripheral surface 17 of the insertion portion 16 functions as an operation space that allows the displacement of the extrusion sleeve 81 in the radial direction. Become.

  Immediately after the entire large diameter portion 88 of the extrusion sleeve 81 protrudes from the opening 55, the taper portion 86 of the extrusion sleeve 81 and the taper portion 66 of the center pin 61 come into contact with each other. By continuing the displacement of the extrusion sleeve 81 in the extrusion direction, the extrusion sleeve 81 is displaced in the radial direction along the inclination of the tapered portions 66 and 86. Here, the divided pieces 81a to 81d constituting the extrusion sleeve 81 are not coupled to each other, and the mutual distance is expanded by the displacement. As shown in FIG. 3, the fitting portion 73 of the extrusion base portion 71 also has a clearance that allows movement of the extrusion sleeve 81 in the radial direction. As a result, each of the divided pieces 81a to 81d does not displace only on the cavity C side, but slides in the radial direction as a whole.

  Here, the relationship between the amount of displacement in the radial direction and the undercut forming groove 92 and the annular protrusion 105 will be described. As shown in FIG. 4C, the displacement amount (that is, the difference between the radial dimension of the small diameter portion 87 and the radial dimension of the large diameter portion 88) is the amount of protrusion of the annular protrusion 105 from the movable side cylinder portion 102 ( That is, it is set larger than the depth dimension of the undercut forming groove 92 from the surface of the recess 91. More specifically, in the present embodiment, the extrusion sleeve 81 is constituted by four divided pieces having the same size, and the moving directions thereof are orthogonal to each other. In such a configuration, there is a difference in the amount of increase in the gap between the central portion (that is, the portion perpendicular to the moving direction) and the end portion in the circumferential direction of the divided pieces 81a to 81d. Specifically, as the distance from the central portion increases, the amount of increase in the gap becomes smaller, and the amount of increase in the gap becomes smaller at both ends compared to the central portion. Therefore, the amount of displacement in the present embodiment is set so that interference can be avoided at both ends.

  Thereafter, as shown in FIG. 5C, the small-diameter portion 84 of the extrusion sleeve 81 and the large-diameter portion 65 of the center pin 61 are in contact with each other, and the radial displacement is restricted. Such a state is an allowable state in which removal of the cast product 100 is allowed.

  In the allowable state, the range in which the extruded sleeve 81 is sandwiched between the inside and the outside is smaller than that in the initial state shown in FIG. However, in the permissible state where the cast product 100 only needs to be removed compared to the initial state in which casting is performed, even if the position accuracy is lowered, it is possible to avoid adversely affecting the accuracy of the cast product.

  Next, the movement of the extrusion sleeve 81 when returning to the initial state will be described. After the extrusion of the cast product 100 is completed, the pressing by the extrusion driving unit is released. As a result, the extrusion base portion 71 is retracted by the biasing force of the coil spring 76. Following this, the extrusion sleeve 81 is also retracted.

  As shown in FIG. 5C → FIG. 5B, when the extrusion sleeve 81 is retracted, the extrusion sleeve 81 reaches a position where the tapered portions 66 and 86 are in contact with each other. Thereby, the displacement to a diameter reduction direction will be accept | permitted.

  Thereafter, the outer tapered portion 89 of the extrusion sleeve 81 hits the edge of the opening 55 in the insertion portion 16. When the outer tapered portion 89 is pressed against the edge portion by the urging force of the coil spring 76, the pushing sleeve 81 is displaced inward of the insertion portion 16 along the inclination of the outer tapered portion 89, and the expanded diameter state is changed to the normal state. Return.

  By continuing the backward movement of the extrusion sleeve 81, the outer large diameter portion 88 of the extrusion sleeve 81 is accommodated in the insertion portion 16. Accordingly, the outer large diameter portion 88 contacts the inner peripheral surface 17 of the insertion portion 16 and the inner large diameter portion 85 contacts the large diameter portion 65 of the center pin 61.

  And the return to the initial state shown to Fig.5 (a) will be completed because the extrusion sleeve 81 reverse | retreats to the position where the center pin 61 and the extrusion base part 71 contact | abut.

  Based on the operation of the product extrusion mechanism 70 described in detail above, the manufacturing process of the cast product 100 will be described. In the following description, reference will be made to FIGS. 6 to 9 are schematic views showing the manufacturing process.

  As shown in FIG. 6A, the cavity C is formed by the fixed mold 11 and the movable mold 12 in a state where the die casting apparatus 10 is in the mold closed state. Under such circumstances, when molten metal is poured from the gate 28 (see FIG. 1), the molten metal flows into the cavity C through the molten metal path.

  The molten metal hardens when a predetermined cooling period elapses after the molten metal is injected into the cavity C. Then, as shown in FIG.6 (b), the die-cast apparatus 10 switches to a mold open state by moving the movable metal mold | die 12. FIG. When the movable mold 12 moves, the cast product 100 moves following the movable mold 12 by being caught by the extrusion sleeve 81 and the annular protrusion 105.

  After the die casting apparatus 10 is switched to the mold open state, the extrusion operation by the product extrusion mechanism 70 is started. Specifically, when the extrusion base portion 71 is pressed by the extrusion rod R, the extrusion base portion 71 moves against the urging force of the coil spring 76. Following the movement of the extrusion base 71, the extrusion sleeve 81 also moves.

  As shown in FIG. 6B, the distal end portion of the extrusion sleeve 81 is in contact with the cast product 100 (specifically, the connecting portion 103 and the movable side cylinder portion 102) from the side opposite to the fixed mold 11. For this reason, as shown in FIG. 6B → FIG. 7C, the cast product 100 is pushed out to the side protruding from the housing recess 53 by the movement of the extrusion sleeve 81. At this time, at least until the fixed-side cylinder portion 101 is separated from the center pin 61, the large-diameter portion 88 of the extrusion sleeve 81 and the inner peripheral surface 17 of the insertion portion 16 are maintained in contact with each other. As a result, it is possible to avoid the occurrence of inconvenience that the casting product 100 is inclined and the extrusion becomes difficult.

  As shown in FIG. 7C, the entire large diameter portion 88 of the extrusion sleeve 81 protrudes from the insertion portion 16 after the movable side cylindrical portion 102 of the cast product 100 is completely detached from the insertion portion 16. . Thereby, the space between the extrusion sleeve 81 and the inner peripheral surface 17 of the insertion portion 16 functions as an operation space that allows the movement of the extrusion sleeve 81 in the diameter expansion direction.

  As shown in FIG. 7 (c) → FIG. 7 (d), by continuing the movement of the extrusion base portion 71, the taper portion 86 of the extrusion sleeve 81 contacts the taper portion 66 of the center pin 61, and the extrusion sleeve. 81 moves sideways along the inclination of the tapered portions 66 and 86. Thereby, the space | interval of each division piece 81a-81d which comprises the extrusion sleeve 81 becomes large, and the undercut formation groove | channel 92 will space apart from the cyclic | annular protrusion 105. FIG. As a result, a passage region of the fixed-side cylinder portion 101 including the annular protrusion 105 is secured in the extrusion sleeve 81.

  As shown in FIG. 7 (d) → FIG. 8 (e), after the extruded sleeve 81 is switched to the expanded diameter state, the small diameter portion 87 of the extruded sleeve 81 contacts the inner peripheral surface 17 of the insertion portion 16, and The small diameter portion 84 abuts on the large diameter portion 65 of the center pin 61. Thereby, the extrusion sleeve 81 is maintained in an expanded state. When the extrusion sleeve 81 reaches the maximum projecting position, the entire cast product 100 projects from the housing recess 53, and the cast product 100 is taken out.

  After the series of operations detailed above is completed, the die casting apparatus 10 is switched to the closed state.

  Specifically, first, the pressing by the push driving unit is released. Thereby, the pushing sleeve 81 moves toward the initial position by the urging force of the coil spring 76 (see FIG. 1). At this time, first, the taper portion 86 of the extrusion sleeve 81 reaches the taper portion 66 of the center pin 61, and at a timing immediately thereafter, the taper portion 89 of the extrusion sleeve 81 is opened as shown in FIG. It contacts the edge of the portion 55.

  The push-out sleeve 81 returns to the normal state from the diameter-expanded state by being pushed toward the diameter-reduced side by the edge of the opening 55. That is, as shown in FIG. 9G, the large diameter portion 85 of the extrusion sleeve 81 is in contact with the large diameter portion 65 of the center pin 61 and the small diameter portion 84 is in contact with the small diameter portion 64 of the center pin 61. Become.

  Thereafter, the movement of the pushing sleeve 81 by the biasing force of the coil spring 76 is continued, and the pushing base portion 71 reaches a position where it abuts against the fixed base portion 61b of the center pin 61, whereby the pushing sleeve 81 stops moving backward. Thereby, the return to the initial state is completed (see FIG. 9H).

  After the completion of the return to the initial state is detected based on a signal from a sensor or the like, the movable mold 12 is moved to the closed position as shown in FIG. 9 (h) → FIG. 6 (a). As a result, the die casting apparatus 10 is switched to the mold closed state. This completes preparation for molding the next cast product.

  In the present embodiment, by adopting a configuration in which the diameter of the extrusion sleeve 81 is increased based on the extrusion operation of the cast product 100, the catch between the undercut forming groove 92 and the annular protrusion 105 as the undercut portion is released. did. Thereby, the restriction | limiting with respect to the shape of the casting product 100 is suppressed. Hereinafter, the reason will be described with reference to FIG. FIG. 10 is a schematic view showing the relationship between the movable mold 12 having the undercut forming groove 92 and the cast product 100.

  As shown in FIG. 10 (a), the connecting portion 103 of the cast product 100 bulges so as to be convex on the side opposite to the fixed mold 11, and the bottom of the accommodating recess 53 of the movable side insert 51. In correspondence with this bulging portion, a recess that is concave is formed on the side opposite to the fixed mold 11. In such a configuration, for example, the slide core FS shown in FIG. 10A can be adopted, and the annular protrusion 105 can be formed by the slide core FS. However, if the slide core FS is to be retracted by following the movement of the movable mold 12 when the mold is opened, the following inconvenience may occur. That is, since the cast product 100 remains in a state of being fitted in the housing recess 53, the slide core FS is hindered by being caught by the connecting portion 103 of the cast product 100, thereby preventing the movement of the slide core FS.

  By adopting the slide core FS and devising its movement, if it is attempted to avoid catching with the connecting portion 103, not only the moving direction of the slide core FS is easily restricted, but also the slide core FS is moved. It is assumed that the mechanism is complicated.

  In this regard, in the present embodiment, as shown in FIG. 10B, a configuration is adopted in which the diameter of the extrusion sleeve 81 is increased after the cast product 100 is extruded to a position away from the bottom of the housing recess 53. Thus, an operation space for the extrusion sleeve 81 can be secured in the housing recess 53. Therefore, the diameter expansion operation of the extrusion sleeve 81 is not hindered by the connecting portion 103 or the accommodation recess 53 of the cast product 100. Thereby, compared with the case where the said slide core FS is employ | adopted, the restriction | limiting with respect to the shape of a cast product can be reduced.

  According to the first embodiment described in detail above, the following excellent effects are obtained.

  By casting with the die casting apparatus 10, not only the cylindrical portions 101 and 102 and the connecting portion 103 constituting the main body portion of the cast product 100, but also the annular protrusion 105 as an undercut portion is integrally formed. Thereby, the additional process for forming an undercut part becomes unnecessary, and reduction of a manufacturing process and manufacturing cost is realizable. Further, by integrally forming the undercut portion in this way, it is possible to expect the suppression of the cast hole, and thus contribute to the quality improvement of the cast product 100.

  An extrusion sleeve 81 is employed as a means for forming the undercut portion. The extrusion sleeve 81 is configured to be displaced away from the undercut portion based on the extrusion operation of the cast product 100. In this way, by linking the push-out operation of the cast product 100 and the avoidance operation of the undercut part, a dedicated drive means is not required for performing the avoidance operation. By using the drive means for product extrusion, which is normally provided in the mold apparatus, as the drive means for the avoidance operation as it is, the complexity of the structure of the mold apparatus is suppressed.

  The above avoidance operation is completed until the extrusion of the cast product 100 by the extrusion sleeve 81 is completed, that is, until the entire cast product 100 protrudes from the housing recess 53. Thus, the increase in the extrusion stroke is suppressed by adopting a configuration in which the avoidance operation is completed in the movement section from the standby position to the extrusion completion position. Thereby, it can contribute to shortening the waiting time of the taking-out operation | work of the casting product 100, and mass production of the casting product 100 can be implement | achieved suitably.

  The extrusion sleeve 81 is configured to ensure the extrusion function of the cast product 100 even during the transition to the expanded state, that is, during the displacement in the radial direction. Thereby, it is avoided that the period required for extrusion of the cast product 100 becomes long. In addition, by maintaining the extrusion function, it is possible to make it difficult for the casting product 100 to drop and the like to prevent the extrusion sleeve 81 from being displaced in the radial direction.

  When the extrusion sleeve 81 is movable, the molding accuracy of the cast product 100 may be lowered due to an unstable posture of the extrusion sleeve 81 during molding. This is not preferable because the quality of the cast product 100 is deteriorated.

  In this regard, in the present embodiment, when the extrusion sleeve 81 is arranged at the standby position, the extrusion sleeve 81 is sandwiched between the inner peripheral surface 17 of the insertion portion 16 and the center pin 61. . Thereby, the displacement of the extrusion sleeve 81 (specifically, each of the divided pieces 81a to 81d) in the direction intersecting with the central axis CL is restricted, and it is possible to suitably avoid the reduction in the molding accuracy.

  Further, when the cast product 100 is extruded, the reaction force that can be generated by the extrusion becomes the largest in the initial stage of extrusion. Furthermore, it is assumed that the reaction force is relatively likely to occur until the tapered portion 67 of the center pin 61 is removed from the movable side tubular portion 102 of the cast product 100. Therefore, at least at the start of extrusion (specifically, until the tapered portion 67 is detached from the movable cylinder portion 102), the above-mentioned sandwiched state is maintained, and the extrusion sleeve 81 in the direction intersecting the central axis CL is maintained. By restricting the displacement, it is possible to suppress the deformation of the extrusion sleeve 81 due to the reaction force.

  When the large diameter portion 85 of the extrusion sleeve 81 protrudes from the opening 55 of the insertion portion 16, the displacement of the extrusion sleeve 81 in the radial direction is not hindered by the movable side insert 51 or the cast product 100. For this reason, the transition to the extended state described above can be performed smoothly.

  After the transition to the expanded state, the extrusion sleeve 81 is again held between the inner peripheral surface 17 of the insertion portion 16 and the outer peripheral surface 62 of the center pin 61. Thereby, the posture of the extrusion sleeve 81 can be stabilized. This is preferable in order to avoid catching between the extrusion sleeve 81 and the annular protrusion 105 when the cast product 100 is taken out. In other words, since the posture can be stabilized, the amount of displacement of the extrusion sleeve 81 in the radial direction can be suppressed. Thereby, a series of operations of the extrusion sleeve 81 can be completed quickly.

  In the present embodiment, a configuration is adopted in which the extrusion sleeve 81 is constituted by a plurality of divided pieces 81a to 81d, and each of the divided pieces 81a to 81d is individually displaced in the radial direction. Thereby, it is possible to reduce the displacement amount of the extrusion sleeve 81 required for forming a gap for avoiding the catching with the annular protrusion 105. Thereby, the switching to the expanded state is made quick.

  In particular, by unifying the sizes of the divided pieces 81a to 81d, the amount of displacement required for the individual divided pieces 81a to 81d is made uniform. This contributes to quick switching to the expanded state.

<Second Embodiment>
In the first embodiment described above, the catch with the undercut portion is avoided based on the extrusion operation of the cast product 100. However, in the present embodiment, this avoidance configuration is the first. This is different from the embodiment. Hereinafter, with reference to FIG. 11, the die casting apparatus 10Z in this Embodiment is demonstrated centering on difference with 1st Embodiment.

  As shown in FIG. 11A, the center pin 61Z of the die casting apparatus 10Z is provided with a large diameter portion 65Z on the base end side and a small diameter portion 64Z on the distal end side, and the large diameter portion 65Z and the small diameter portion 64Z are tapered. They are connected by the portion 66Z, and the magnitude relationship is opposite to that of the center pin 61 of the first embodiment.

  A movable sleeve 81Z having a substantially cylindrical shape is provided between the center pin 61Z and the inner peripheral surface 17Z of the insertion portion 16Z. The movable sleeve 81Z corresponds to the extrusion sleeve 81 in the first embodiment, but unlike the extrusion sleeve 81, the extrusion function of the cast product 100 is not given.

  One end of the movable sleeve 81Z is attached to the movable base 71Z. The outer shape of the movable base 71Z is the same as that of the extrusion base 71 of the first embodiment, but the operation mode is different. Specifically, the tip end portion of the tension rod extending from the tension drive unit is fixed, and the tension rod moves to the side away from the main body portion 42 of the movable mold 12Z, thereby moving following the tension rod. . As a result, the movable sleeve 81Z moves backward.

  The inner peripheral surface 82Z of the movable sleeve 81Z has a large diameter portion 85Z that contacts the large diameter portion 65Z of the center pin 61Z, a small diameter portion 84Z that contacts the small diameter portion 64Z of the center pin 61Z, and the large diameter portion 85Z and the small diameter. It has a tapered portion 86Z that connects the portion 84Z and abuts against the tapered portion 66Z of the center pin 61Z.

  Thus, the state in which the large diameter portions 65Z and 85Z, the small diameter portions 64Z and 84Z, and the taper portions 66Z and 86Z are in contact with each other is the initial state of the core unit 18Z in the present embodiment.

  On the outer peripheral surface 83Z of the movable sleeve 81Z, the configuration corresponding to the small diameter portion 87 and the large diameter portion 88 shown in the above embodiment is omitted, and is formed so as to have the same diameter in the entire region excluding the tip portion. . A tapered portion 89Z is formed at the tip portion of the outer peripheral surface 83Z. As a result, the movable sleeve 81Z is tapered.

  On the inner peripheral surface 17Z of the insertion portion 16Z provided in the movable mold 12Z, a tapered portion 19Z is formed so that the hole diameter gradually decreases toward the opening portion 55Z. The tapered portion 89Z of the movable sleeve 81Z comes into contact with the tapered portion 19Z. That is, in the initial state, the position of the movable sleeve 81Z is determined by the taper portion 89Z of the movable sleeve 81Z being pressed against the taper portion 19Z.

  In the present embodiment, unlike the above embodiment, a configuration corresponding to the return pin 75 and the coil spring 76 is disposed between the movable base portion 71Z and the mounting plate 44, and corresponds to the coil spring. The movable sleeve 81Z is pressed against the tapered portion 19Z by the urging force of the configuration.

  Here, with reference to Fig.11 (a) and FIG.11 (b), operation | movement of the product extraction mechanism 70Z when removing the cast product 100 from the die-casting apparatus 10Z is demonstrated.

  After the molten metal injected into the cavity C is solidified and the die casting apparatus 10Z is switched to the mold open state, the movable drive part 71Z moves to the side away from the main body part 42Z by operating the tension drive part. Following this, the movable sleeve 81Z also moves. At this time, as shown in FIG. 11B, the movable sleeve 81Z moves in the radial direction of the central axis CL along the inclination of the tapered portions 66Z and 86Z.

  An operation space allowing movement of the movable sleeve 81Z is provided between the outer peripheral surface 83Z of the movable sleeve 81Z and the inner peripheral surface 17Z of the insertion portion 16Z, and the movable sleeve 81Z that has moved through this operation space has its outer peripheral surface. When 83Z abuts against the inner peripheral surface 17Z, further movement in the diameter expansion direction (radial direction) is restricted.

  Thus, since the taper portions 66Z and 86Z are kept in contact with each other even when the movement in the diameter expansion direction is restricted, further retreat of the movable sleeve 81Z is also restricted.

  When the movable sleeve 81Z is expanded in this way, the undercut forming groove 92 is separated from the annular protrusion 105 of the cast product 100. More specifically, when the cast product 100 is removed, the undercut forming groove 92 is separated from the path through which the annular protrusion 105 passes. Thereby, removal of the cast product 100 is permitted.

  After the cast product 100 is removed, the pulling by the pulling drive unit is ended, and the movable base 71Z and the movable sleeve 81Z are returned to the initial positions by the biasing force of the coil spring (see FIG. 11A).

  According to the second embodiment described in detail above, after the die casting apparatus 10 is switched to the mold open state, the catch between the annular protrusion 105 as the undercut part and the movable mold 12 can be eliminated.

<Third Embodiment>
In the first embodiment, the extrusion base portion 71 (extrusion sleeve 81) constituting the product extrusion mechanism 70 is returned to the initial position by the biasing force of the coil spring 76, but in the present embodiment, The configuration relating to the return of the extrusion base portion 71 (extrusion sleeve) to the initial position is different from that of the first embodiment. Hereinafter, the different configuration will be described with reference to FIG. 1 again.

  In the present embodiment, the distal end portion of the extrusion rod R provided in the hydraulic cylinder device is connected to the extrusion portion (for example, the extrusion base portion 71) of the die casting device 10, and follows the piston movement of the extrusion rod R. The extrusion base portion 71 is configured to move. That is, the driving force for returning the extrusion base portion 71 to the initial position is supplied from the hydraulic cylinder device. In addition to this change, the coil spring 76 shown by the two-dot chain line in FIG. 1 is omitted, and the configuration for operating the pushing sleeve 81 is simplified.

  After the casting product 100 is extruded, the extrusion rod R is retracted, whereby the extrusion base portion 71 is pulled toward the initial position. As described above, if the extrusion base R is forcibly returned to the initial position using the extrusion rod R, the return function of the extrusion sleeve 81 is ensured even if the coil spring 76 described above is omitted. Here, in a die casting apparatus adopting a configuration corresponding to the coil spring 76 as in the die casting apparatus shown in the first embodiment, for example, the driving force of the associated hydraulic cylinder device (specifically, the casting product is pressed). It is necessary to allow for a force to resist the urging force of the coil spring in the driving force at the time of ejection. In this regard, as shown in the present embodiment, if the configuration does not depend on the urging force such as a coil spring, the above-described expectation becomes unnecessary. Thereby, it can contribute to reduction of the load which arises in a hydraulic cylinder device.

  The technical idea shown in the present embodiment (a configuration in which the return coil spring is omitted and the rod is connected to the drive unit of the die casting apparatus) may be applied to the second embodiment. In this case, the movable sleeve 81Z and the movable base portion 71Z are pushed back to the initial positions by returning the tensile rod to the original position after the casting product is taken out.

<Other embodiments>
The present invention is not limited to the description of the above embodiments, and may be implemented as follows, for example.

  (1) In each of the above embodiments, the product extruding mechanism 70 is disposed on the movable mold 12 side of the fixed mold 11 as the “fixed mold” and the movable mold 12 as the “movable mold”. Alternatively, a configuration corresponding to the product extrusion mechanism 70 may be arranged on the fixed mold 11 side. In such a modified example, when the mold is opened, the cast product remains on the stationary mold 11 side. Therefore, an extrusion mechanism is provided in the stationary mold, and the extrusion mechanism operates in synchronization with the mold opening operation. It is preferable to have a structure to be made.

  (2) In each of the above embodiments, a part of the cavity C is provided between the center pin 61 as the “shaft portion” and the extrusion sleeve 81 as the “undercut forming portion”. It is not limited to this. For example, the tapered portion 67 of the center pin 61 may be omitted, and the entire region surrounded by the recess 91 may be a part of the cavity C.

  (3) In the first embodiment, the extrusion sleeve 81 as the “undercut forming portion” has a function of extruding the cast product 100 as the “molded product” from the movable mold 12. It is not limited to. As for the extrusion sleeve 81, it is sufficient if it has a configuration that is linked to the extrusion operation of the cast product 100, and a dedicated part having an extrusion function may be separately provided. However, in order to simplify and miniaturize the configuration of the die casting apparatus 10, it is desirable to provide an extrusion function to the extrusion sleeve 81 as shown in the first embodiment.

  (4) In the first embodiment, the cast product 100 as the “molded product” is separated from the insertion portion 16 after the portion where the annular protrusion 105 as the “undercut portion” is formed. While the product 100 has been configured to complete the switching of the extrusion sleeve 81 to the expanded state before reaching the extrusion completion position, the present invention is not limited to this. For example, after the cast product 100 reaches the extrusion completion position (see FIG. 8E), the extrusion sleeve 81 may be switched to the expanded diameter state. However, in consideration of shortening of the manufacturing period of the cast product 100, it is desirable to complete the switching to the expanded diameter state until the extrusion of the cast product 100 is completed.

  (5) In the first embodiment, the taper portion 66 of the center pin 61 and the taper portion 86 of the extrusion sleeve 81 are used together as means for switching the extrusion sleeve 81 to the expanded diameter state. However, the present invention is not limited to this. It is not something. It suffices that at least one of the tapered portions is employed, and the other tapered portion can be omitted.

  (6) In the first embodiment, the extrusion function applied to the extrusion sleeve 81 is effective even during switching to the expanded diameter state, that is, during movement of the extrusion sleeve 81 in the radial direction. . It is also possible to change this and adopt a configuration in which the extrusion function stops during switching to the expanded diameter state. However, when making such a change, it is desirable to devise measures to avoid the interference between the connecting portion 103 of the cast product 100 and the extrusion sleeve 81 when the extrusion sleeve 81 moves in the radial direction. .

  (7) In each of the above embodiments, when the diameter is expanded, the push sleeve 81 and the movable sleeve 81Z are brought into the diameter expansion position by the inner peripheral surface 17 of the insertion portion 16 and the outer peripheral surface 62 of the center pin 61. However, the present invention is not limited to this. It is sufficient that at least the displacement of the extruded sleeve 81 or the like to the enlarged diameter position is allowed, and the function of holding at the enlarged diameter position can be omitted. However, in consideration of workability when the cast product 100 is removed from the extrusion sleeve 81 and the like, it is desirable that the extrusion sleeve 81 is held at the diameter-expanded position.

  (8) In each of the above embodiments, the extrusion base portion 71 and the movable base portion 71Z are adopted as the driving force transmission means from the drive mechanism. However, the extrusion base portion and the movable base portion 71Z are not essential configurations. It is also possible to adopt a configuration in which a rod or the like extending from the drive mechanism is directly connected to the extrusion sleeve 81, the movable base 71Z or the like.

  (9) In the first embodiment, the extrusion sleeve 81 is configured by the four divided pieces 81a to 81d, but the number of the divided pieces is arbitrary. If the number of divided pieces is increased, the amount of displacement of each divided piece in the radial direction can be made relatively small, and the operating space for expanding the diameter of the push sleeve can be made small.

  Further, it is not always necessary to form the divided pieces so that all the pieces have the same size, that is, the occupation ratio in the extrusion sleeve 81 is the same, and the size of each divided piece is different. It is also possible.

  However, when considering making the operation space of the extrusion sleeve 81 compact, it is preferable to unify the sizes of the divided pieces and set the number of the divided pieces to 3 or more.

  Although the displacement direction of the divided pieces can be different from the radial direction of the central axis CL, the displacement direction is preferably the radial direction of the central axis CL in view of securing the operation space. .

  (10) In each of the above embodiments, the die casting apparatus 10 that manufactures an aluminum cylindrical member as the cast product 100 is assumed. However, metals other than aluminum (for example, zinc, magnesium, copper, lead, tin, and the like) Alloys etc.) may be used as the casting metal. Further, the cast product manufactured by the mold apparatus is not limited to the cylindrical member, and the configuration of the above-described embodiment can be used for forming the hollow portion of the cast product having an undercut portion.

  Further, the problem relating to the undercut portion is not unique to a casting mold apparatus, but can also occur in a mold apparatus for injection molding (for synthetic resin material). Therefore, by applying the technical idea shown in the above embodiment to a mold apparatus for injection molding, it is possible to suitably contribute to mass production of a synthetic resin product having an undercut portion.

  DESCRIPTION OF SYMBOLS 10 ... Die casting apparatus as a mold apparatus, 11 ... Fixed mold as a fixed mold, 12 ... Movable mold as a movable mold, 16 ... Insertion part, 17 ... Inner peripheral surface, 18 ... Core unit, 21 ... Fixed mother Mold 31, fixed side nesting 32, mating surface 33, raised portion 41, movable mother mold 51, movable nesting 52, mating surface 53, receiving recess 55, opening 61, center pin 62 ... outer peripheral surface, 64 ... small diameter part, 65 ... large diameter part, 66 ... taper part, 70 ... product extrusion mechanism, 71 ... extrusion base part, 81 ... extrusion sleeve as undercut forming part, 81a to 81d ... divided pieces, 82 ... Inner peripheral surface, 83 ... Outer peripheral surface, 84 ... Small diameter part, 85 ... Large diameter part, 86 ... Tapered part, 87 ... Small diameter part, 88 ... Large diameter part, 89 ... Tapered part, 91 ... Recessed part, 92 ... Under Cut forming part, 100 ... made by casting as a molded product , 103 ... connecting portion, 105 ... annular projection of the undercut, C ... cavity, CL ... center axis.

Claims (10)

In a mold apparatus having a first mold and a second mold, and a cavity is formed by combining the first mold and the second mold,
An extrusion mechanism for extruding a molded product molded in the cavity from the first mold to the second mold side in a state where the first mold and the second mold are separated from each other;
The first mold has a plurality of mold components forming a part of the cavity,
At least one of the mold components is an undercut forming portion that is provided so as to be displaceable in a direction that intersects an extrusion direction of the molded product by the extrusion mechanism, and that forms an undercut portion of the molded product,
The undercut forming portion intersects the undercut forming portion based on an extrusion operation of the extrusion mechanism in a state where the molded product is extruded from the molding position engaging with the first mold to a predetermined extrusion position by the extrusion mechanism. Bei give a guiding portion for separating the undercut forming part of the undercut portion by inducing direction,
The mold structure of the first mold has a body forming part that forms a body part other than the undercut part in the molded product as a mold structure other than the undercut forming part,
The undercut forming portion is configured to be displaced from the initial position toward the second mold side in accordance with the extrusion operation by the extrusion mechanism,
In the main body forming portion, when the undercut forming portion is disposed at an initial position, the undercut forming portion is displaced in the intersecting direction by contacting a predetermined portion of the undercut forming portion. The main body side contact part to be controlled is formed,
When the undercut forming part is displaced to the second mold side and reaches a predetermined position, the main body side contact part and the predetermined part are separated from each other in the pushing direction in the intersecting direction. Displacement regulation is canceled and guidance of the undercut formation part by the guidance part is permitted .   The mold apparatus according to claim 1, wherein the guide unit completes the guide of the undercut forming unit while the molded product is being extruded by the extrusion mechanism. The undercut forming part has a part that comes into contact with the molded product waiting in a molding position from the front side in the extrusion direction,
The mold apparatus according to claim 1 or 2, wherein the extrusion mechanism is configured to extrude the molded product by displacing the undercut forming portion in the extrusion direction. The main body forming portion is formed with an accommodating portion that extends in the same direction as the extrusion direction and accommodates the undercut forming portion,
The guiding portion is
For guiding that is provided in one of the portion facing the undercut forming portion in the main body forming portion and the portion facing the main body forming portion in the undercut forming portion and is inclined toward the extrusion direction. An inclined part,
The undercut forming portion provided in the other of the portion facing the undercut forming portion in the main body forming portion and the portion facing the main body forming portion in the undercut forming portion. A guide abutting portion that abuts on the guiding inclined portion by the displacement of
The undercut formation unit, by reaching the office stereotactic location is configured such that the state of the portion forming the said cavity in said undercut formation portion is projected from the accommodating portion,
The guiding abutment, claims, characterized in that said undercut formation part by the extrusion is formed so as to abut against the guiding slope portion was during or after reaching the office stereotactic location The mold apparatus according to any one of claims 1 to 3 . The main body forming portion has a shaft portion that extends in the same direction as the housing portion and is housed in the housing portion,
A plurality of the undercut forming portions are disposed between the outer surface of the shaft portion and the inner surface of the housing portion,
A cylindrical body that extends in the same direction as the shaft portion and surrounds the shaft portion is formed by these undercut forming portions,
In a state where the undercut forming portion is disposed at the initial position of the undercut forming portion, a part of the cavity is formed between the undercut forming portion and the shaft portion,
One of the guiding inclined portion and the guiding contact portion is provided in the shaft portion, and the other of the guiding inclined portion and the guiding contact portion is provided in each of the undercut forming portions,
The extrusion by the by the undercut forming portion induction of the undercut formation unit by the induction unit reaches the time or after the office stereotactic location is performed, the radiation direction of each undercut forming portion the shaft portion 5. The mold apparatus according to claim 4 , wherein the mold body is expanded so that an inner diameter of the cylindrical body is allowed to pass through the molded product. The accommodating portion has a round hole shape extending in the same direction as the extrusion direction, and the shaft portion is arranged coaxially with a central axis thereof.
The cylindrical body has a substantially cylindrical shape,
Each of the undercut forming portions is at least in an initial position so that an outer surface thereof is in contact with an inner surface of the housing portion, and an inner surface of the undercut forming portion is in contact with an outer surface of the shaft portion. The mold apparatus according to claim 5 , wherein the mold apparatus is formed. The receiving portion, the shaft portion and the respective undercut forming unit until said undercut formation unit reaches the plant localization location abuts the outer surface of the undercut forming portion on an inner surface of said housing portion, said The mold apparatus according to claim 6 , wherein the undercut forming portion is formed so as to maintain a state in which the inner surface of the undercut forming portion is in contact with the outer surface of the shaft portion. On the outer peripheral surface of the cylindrical body, an outer large-diameter portion as the predetermined portion , and the outer large-diameter portion is located on the side opposite to the second mold, and is outside the outer large-diameter portion. An outer small diameter portion having a small diameter is formed,
In the state where the cylindrical body is disposed at the initial position of the cylindrical body, the outer large diameter portion abuts on the inner surface of the housing portion, and the outer small diameter portion and the inner surface of the housing portion are spaced apart from each other. Facing each other,
By the outer large-diameter portion when the tubular body has reached the plant localization location protrudes from the accommodating portion, the gap between the inner surface of said housing portion and the outer diameter portion each under during the induction The mold apparatus according to claim 6 or 7 , wherein the mold apparatus functions as an operation region of the cut forming unit. On the inner peripheral surface of the undercut forming portion,
An inner small diameter part,
An inner large-diameter portion that is provided closer to the second mold than the small-diameter portion and has an inner diameter set larger than the small-diameter portion;
An inner connecting portion connecting the inner small diameter portion and the inner large diameter portion is formed,
On the outer peripheral surface of the shaft portion,
When the undercut forming portion is disposed at least at the initial position of the undercut forming portion, the shaft-side small diameter portion that contacts the inner small diameter portion;
When the undercut forming portion is disposed at least at the initial position of the undercut forming portion, the shaft-side large diameter portion that contacts the inner large diameter portion;
A shaft side connecting portion that connects the shaft side small diameter portion and the shaft side large diameter portion is formed,
Either one of the inner connecting portion and the shaft side connecting portion is the guiding inclined portion, and the other is the guiding contact portion,
In a state in which the undercut formation portion is displaced induced position by the guide portion, any one of claims 6 to 8, characterized in that said inner diameter portion and the shaft-side large-diameter portion comes into contact The mold apparatus as described in. It said body forming portion, the undercut forming portion reaches the office stereotactic location, in the state where the molded product is extruded in the predetermined pushing position, the guiding destination of the undercut formation section by the guiding section mold apparatus according to any one of claims 1 to 9, characterized in that operation space of the undercut formation portion is formed so as to be secured to a portion made.

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