JP6662550B2 - Mold for molding two-color molded products characterized by a screw removal mechanism - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a mold for molding a two-color molded article having female threads, such as a lid for a container having a lid having female threads formed thereon and a design portion laminated on the surface of the lid. It is.

  The resin lid provided on the container has a female screw formed on the inner peripheral surface thereof, and is screwed to a male screw formed on the mouth of the container to close the container. The lid provided with such a threaded portion can be formed by injection molding using a mold having a predetermined core as described in Patent Document 1, for example. In one mold, a concave portion is formed in the parting line so that the outer peripheral surface of the lid can be formed. The other mold is provided with a cylindrical core protruding from the parting line and rotatable with respect to the mold. The core has a male screw formed on the cylindrical surface. When the mold is clamped and the resin is injected, a lid is formed. After cooling and solidifying, open the mold. When the core is rotated, the male screw of the core comes off from the female screw formed on the lid. That is, the screws are removed. This gives a lid.

  Some lids made of resin have excellent design, such as lids for containers of high-grade cosmetics. For example, there is a lid made of two kinds of resins as such a lid, and a design part made of a second resin is laminated on a lid made of a first resin. Such a two-color molded article made of two kinds of resins can be molded by a so-called die slide injection method. In the mold used in this molding method, one mold is slid relative to the other mold and clamped at two positions. For example, in a mold for molding a lid of a two-color molded product, one mold is provided with a core having an external thread, and the other mold is provided with a concave portion for primary molding and a concave portion for secondary molding. Are formed. One mold is slid and clamped at the first position. Then, a cavity for the lid is formed by the core and the first recess. The lid is molded by injecting the first resin by primary molding. When opening the mold, leave the lid on the core of one mold. When one of the molds is slid to the second position and the mold is clamped, a cavity for the design part is formed by the lid and the second recess remaining in the core. The second resin is injected by secondary molding. When the mold is opened, the core is rotated, and the screw is removed, a lid having the design portion laminated on the lid is obtained. By the way, the lid of the two-color molded product is sometimes required not only from the design property but also from the functionality. For example, a lid that requires high airtightness needs to be formed of a relatively soft resin at the portion that comes into contact with the end face of the mouth of the container. This is for enhancing the sealing effect. In such a lid, the lid provided with the female screw portion is formed of a relatively hard resin, and the upper portion abutting on the end surface of the mouth of the container is formed of a soft resin.

JP-A-6-183449 JP 2009-72965 A

  By the way, in order to remove a screw from a molded product such as a lid, it is necessary to rotate the core, and the core is generally rotated by a motor. On the other hand, Patent Literature 2 discloses a mold that does not require a special driving mechanism such as a motor and rotates a core by a mold opening operation. The mold described in Patent Literature 2 includes a fixed mold and a movable mold, and the movable mold is provided with a slider that slides horizontally with respect to the movable mold. A guide pin of a predetermined length is fixed to one end of the fixed mold, and extends in the direction of the movable mold at a predetermined angle to the mold opening and closing direction. An oblique hole is formed in the slider, and the guide pin is inserted through this hole. Since the guide pin is provided obliquely to the mold opening and closing direction, when the movable mold is opened and closed with respect to the fixed mold, the slider is guided by the guide pin and is relatively moved with respect to the movable mold. Slide to. A rack is provided on such a slider, and a pinion is provided on a rotating shaft that rotates the core. Since the rack and the pinion are engaged with the rack, when the mold is opened, the slider slides and the core rotates. That is, the screw is removed by the mold opening operation.

  Even if the core is driven by a motor as in the related art, a screw can be removed from a molded product such as a lid. However, there are problems. First, there is a problem that a motor is particularly required for the mold. Providing a motor increases costs and requires a power supply for driving the motor. There is also the problem of design. If a geared motor is used as the motor, it is difficult to accurately control the rotational position of the core. If this is done, the rotational position of the core when the mold is clamped becomes indefinite, so that the female screw of the lid formed by injection molding shifts the rotational position for each lid. Many lids have a predetermined design on the upper surface, but if the rotation position of the female screw is shifted, the design on the upper surface of the lid changes direction for each lid when closing the mouth of the container. I will. That is, the design property is impaired. If the orientation of the design on the top of the lid is not constant, it is also difficult to confirm whether the container is tightly closed. If a servomotor is employed as the motor, the rotational position of the core can be accurately controlled. However, a servomotor requires a servo amplifier, an encoder, and the like, so that the cost increases.

  On the other hand, in the mold described in Patent Document 2, since the core is rotated by the mold opening operation to remove the screw, a motor is unnecessary and the cost is small. Further, since the rotational position of the core is accurately determined by the slide position of the slider, the rotational position of the core can be kept constant when the mold is clamped. Then, the female screw formed on the lid does not shift. Therefore, a lid excellent in design can be formed. However, a problem to be solved is found in the mold described in Patent Document 2. Specifically, there is a problem that it cannot cope with two-color molding. When a lid made of a two-color molded product is molded, when the primary molding is completed and the mold is opened, the lid, which is the primary molded product, needs to be left on the core without being screwed. However, in the mold described in Patent Document 2, the core is rotated in conjunction with the opening of the mold, so that the primary molded product is unscrewed. Then, a two-color molded product cannot be molded.

  Therefore, the present invention is a molding die for molding a two-color molded article having female threads, such as a lid made of two kinds of resins, which is low in cost and has a constant rotational position of the female threads. It is an object of the present invention to provide a molding die capable of molding a molded product.

  In order to achieve the above object, the present invention is configured as a two-color molding die including a fixed die, a movable die, and a slide die that slides on the movable die. A holder hole is formed in the slide mold to accommodate the co-rotating holder, and a core is inserted into the center hole of the co-rotating holder. A pinion is provided at the rear end of the rotating shaft of the core, and a rack is provided at the movable mold so that the core rotates when the slide mold slides. When the slide die is slid so that the core is shifted from the primary molding position to the secondary molding position, the co-rotating holder is rotated integrally with the core and slides from the secondary molding position to the primary molding position. Only the core rotates. A male screw is formed on the head of the core, and when the core is at the primary molding position, the mold is clamped and the first resin is injected to form a primary molded product. When the mold is opened, the slide mold is slid, the core is set at the secondary molding position, the mold is clamped, and the second resin is injected to obtain a two-color molded product. When the core is slid from the secondary molding position to the primary molding position, the core rotates in the unthreading direction and the two-color molded product is released.

  That is, the invention according to claim 1 comprises a fixed mold, a movable mold that is opened and closed with respect to the fixed mold, and a slide mold that is slid on the movable mold. A core is rotatably provided on the mold, and a head of the core is exposed from the slide mold and a male screw is formed on the head. The core is slid by sliding the slide mold. When the mold is clamped at the next molding position, a cavity for primary molding including the head of the core as a part thereof is formed, and when the first resin is injected into the cavity for primary molding, the primary molded article is formed. When the mold is opened, leaving the primary molded product on the core, the slide mold is slid to set the core to the secondary molding position and the mold is clamped. A cavity for secondary molding including as a part is formed, When the second resin is injected into the cavity for the next molding, a two-color molded product is molded, and when the mold is opened and the core is rotated in the unthreading direction, the two-color molded product is released. A predetermined holder hole is formed in the slide die, a co-rotating holder is housed in the holder hole, and the core has a center hole whose rotation axis is formed in the co-rotating holder. Are inserted through the slide mold, a pinion is provided at the rear end of the rotating shaft, and a rack that meshes with the pinion is provided at the movable mold, and the slide mold slides. When the core moves from the primary molding position to the secondary molding position, the core rotates integrally with the co-rotating holder, and the core moves from the secondary molding position to the primary molding position. When said co-rotation The female screw is characterized in that rotation is restricted with respect to the holder hole, and only the core rotates in the unthreading direction, whereby the two-color molded product is released. It is configured as a molding die for a two-color molded product.

The invention according to claim 2 is the molding die according to claim 1, wherein the co-rotating holder is provided with an extrusion plate that is biased by a spring, and the molding die is closed when the molding die is clamped. The extrusion plate is adapted to be pressed by the fixed mold, the mold is opened with the two-color molded product remaining in the core, and when only the core is rotated in the unthreading direction, the two-color molded product is pushed into the extrusion plate. , And is formed as a molding die for a two-color molded product on which a female screw is formed.
According to a third aspect of the present invention, in the molding die according to the first or second aspect, a torque limiter that idles when a predetermined torque or more acts between the co-rotating holder and the rotating shaft of the core. The torque limiter is provided with a ball hole drilled at a predetermined depth radially outward on an inner peripheral surface of the center hole of the co-rotating holder, and a metal hole accommodated in the ball hole. A female screw formed of a ball and a depression formed in the rotation shaft of the core, wherein the metal ball is pressed against the depression by a spring bias. It is configured as a molding die for a two-color molded product.
According to a fourth aspect of the present invention, in the molding die according to the first to third aspects, a rotation direction regulating mechanism that regulates a rotation direction of the co-rotating holder is provided between the slide die and the co-rotating holder. Wherein the rotation direction regulating mechanism includes a locking claw receiving hole formed at a predetermined depth in an inner peripheral surface of the holder hole, and a predetermined locking claw stored in the locking claw storing hole. And a claw hole formed on the outer peripheral surface of the co-rotating holder, wherein the tip of the locking claw is pressed against the claw hole by spring bias, and the locking claw is pressed against the co-rotating holder in one rotational direction. When the torque is applied, the locking claw is pushed up from the claw hole, the locked state of the locking claw and the claw hole is released, and the co-rotating holder rotates. The state where the pawl is locked in the claw hole is maintained and the Wherein the rotation of the holder is adapted to be regulated, configured as a molding die two-color molded article female screw is formed.
According to a fifth aspect of the present invention, in the molding die according to any one of the first to fourth aspects, the slide die has a plurality of sets of two or more sets of the core and the co-rotating holder. And the plurality of sets are divided into a first group and a second group. When the slide die is set at a predetermined slide position, the cores of the first group are at a primary molding position and the second group is The core of the first group is at the secondary molding position and the core of the second group is at the primary molding position when the core is at the secondary molding position and is at another sliding position. As a molding die for a two-color molded product having female threads.

  As described above, the present invention comprises a fixed mold, a movable mold that is opened and closed with respect to the fixed mold, and a slide mold that is slid on the movable mold. , A core is rotatably provided, the head of the core is exposed from the slide mold and a male screw is formed on the head, and the slide mold is slid to move the core to the primary molding position. When the mold is clamped, a cavity for primary molding including the head of the core as a part thereof is formed, and when the first resin is injected into the cavity for primary molding, a primary molded product is molded. The mold is opened while the primary molded product is left on the core, and the slide mold is slid to set the core in the secondary molding position and the mold is clamped for secondary molding including the primary molded product as a part thereof. A cavity is formed, and the second resin is filled in the cavity for the secondary molding. Is when out two-color molded article molded and the then open mold rotating core thread drawing direction two-color molded article is directed to a mold adapted to be demolded. That is, the present invention is directed to a mold for forming a two-color molded product having a female screw, in which a female screw is formed by a male screw of a core. According to the present invention, a predetermined holder hole is formed in the slide mold, a co-rotating holder is housed in the holder hole, and the core is inserted through a center hole whose rotation axis is formed in the co-rotating holder. A pinion is provided at the rear end of the rotary shaft through the slide mold, and a rack that meshes with the pinion is provided at the movable mold. When the slide die slides by the rack and the pinion, the core rotates. Since the rotation is performed by the rack and the pinion, a motor for driving the core is unnecessary, and the cost of the mold is small. Since the rotation position of the core is determined according to the slide position of the slide die, the rotation position of the male screw is always constant in the primary molding. As a result, it is guaranteed that the rotational position of the female screw of the two-color molded product formed thereby is always constant. Since the rotation position of the female screw becomes constant, a resin lid having high designability can be easily formed. According to the present invention, when the slide mold slides and the core moves from the primary molding position to the secondary molding position, the core rotates integrally with the co-rotating holder, and the core is primary molded from the secondary molding position. When moving to the position, the rotation of the co-rotating holder is restricted with respect to the holder hole, and only the core rotates in the unthreading direction, whereby the two-color molded product is released. That is, when the slide mold is slid so that the core is moved from the primary molding position to the secondary molding position, the primary molded product is maintained in the core without being removed from the mold. When the slide mold is slid so that the core is moved from the secondary molding position to the primary molding position after the two-color molded product is formed, the core rotates in the unthreading direction to remove the two-color molded product. Will be typed.

According to another invention, the co-rotating holder is provided with an extruded plate that is biased by spring, and when the molding die is clamped, the extruded plate is pushed by the fixed die. The two-color molded product is extruded by the extrusion plate when the mold is opened with the color molded product remaining and only the core is rotated in the unthreading direction. According to the present invention, since the extrusion plate projects the two-color molded product, an effect that a projection device is not required can be obtained. Predetermined Further, according to another aspect of the present invention, the slide mold plurality of sets with the core and co-rotation holder 2 or more sets of a plurality of sets are provided is divided into a first group and a second group, the slide mold The first group of cores is at the primary molding position while the second group of cores is at the secondary molding position when the first slide group is at the slide position, and the first group of cores is at the second molding position at the other slide positions. The second group of cores is configured to be at the primary molding position. Then, when the primary molding is performed in one of the first and second groups, the secondary molding can be simultaneously performed in the other group, and the primary molding and the secondary molding can always be performed in parallel. . Thereby, a two-color molded product can be molded with high productivity.

FIG. 1 is a front sectional view showing a molding die for a two-color molded product having a female screw according to an embodiment of the present invention and a part of an injection molding machine. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows a part of shaping | molding die of the two-color molded article which has the internal thread which concerns on embodiment of this invention, (A) is a front sectional drawing, (A) is X- in (A). FIG. 4 is a side sectional view of the molding die cut in the X direction. It is a figure which shows typically the shaping | molding method of shape | molding the two-color molded product which has a female screw with the shaping | molding die which concerns on embodiment of this invention, (A)-(E) is the present invention in each process. It is a front sectional view showing the metallic mold for molding concerning an embodiment. It is a figure which shows typically the shaping | molding method of shape | molding the two-color molded product which has a female screw with the shaping | molding die which concerns on embodiment of this invention, (A)-(E) is the present invention in each process. It is a front sectional view showing the metallic mold for molding concerning an embodiment. It is a figure which shows typically the shaping | molding method of shape | molding the two-color molded product which has a female screw with the shaping | molding die which concerns on embodiment of this invention, (A)-(E) is the present invention in each process. It is a front sectional view showing the metallic mold for molding concerning an embodiment. It is a side sectional view showing a part of molding die concerning other embodiments of the present invention.

  Hereinafter, embodiments of the present invention will be described. The molding die 1 according to the present embodiment is a molding die for molding a two-color molded product having female threads, specifically, a lid made of a two-color resin having excellent design. As shown in FIG. 1, the molding die 1 is provided in an injection molding machine 2, and a fixed die 5 attached to a fixed platen 3 of the injection molding machine 2 and a movable plate (not shown) The movable mold 6 is mounted on the fixed mold 5 and is opened and closed with respect to the fixed mold 5. The slide mold 7 is slid on the movable mold 6.

  The stationary mold 5 has a primary molding recess 9 formed at the center of the parting line, and first and second secondary molding recesses 10 and 11 formed above and below the primary molding recess 9. I have. Two sprues are provided on the back surface of the fixed mold 5, and one sprue is touched by the nozzle of the first injection device 13 and the other sprue is touched by the nozzle of the second injection device 14, respectively. The first resin from the first injection device 13 is injected into the primary molding recess 9. The second resin from the second injection device 14 is injected into the first and second secondary molding recesses 10 and 11, but the resin flow path in the fixed mold 5 is not shown. The second resin is injected into only one of the first and second secondary molding recesses 10 and 11 by the switching.

  The movable mold 6 slides the slide mold 7. As will be described in detail later, the movable mold 6 includes first and second racks 18A and 18B for rotating the first and second cores 16A and 16B provided on the slide mold 7. I have. A piston / cylinder unit 21 is provided to slide the slide mold 7 on the movable mold 6.

  The slide die 7 is provided with first and second cores 16A and 16B. The heads of the first and second cores 16A and 16B are exposed from the parting line of the slide mold 7, and male screws are formed on the heads. The male screw can be used to form a female screw into a molded product. Next, the first core 16A will be described in detail with reference to FIG. 2. However, since the first and second cores 16A and 16B have the same structure, the description of the second core 16B will be omitted.

  The first core 16A is provided on the slide mold 7 as follows. As shown in FIG. 2, a predetermined holder hole 22A is formed in the slide die 7, and a co-rotating holder 23A is rotatably housed in the holder hole 22A via bearings 24, 24. I have. A center hole 25A is formed in the co-rotating holder 23A. The first core 16A is rotatable with its rotation shaft 26A inserted into the center hole 25A. A pinion 28A is provided at the rear end of the rotation shaft 26A of the first core 16A. The pinion 28A meshes with the first rack 18A fixed to the movable mold 6. The first rack 18A is provided on the back side with respect to the pinion 28A, and its teeth face the front side of the drawing. Therefore, when the slide mold 7 slides upward in FIG. 2A, the first core 16A rotates in the direction of the arrow Y1 shown in FIG. Will slide in the direction of arrow Y2. The second core 16B is also provided with a pinion 28B on the rotation shaft 26B. The second rack 18B meshing with the pinion 28B is located on the front side of the pinion 28B as shown in FIG. , The teeth of which face the back of the paper. Therefore, when the slide mold 7 slides, the first and second cores 16A and 16B rotate in directions opposite to each other.

  A rotation direction regulating mechanism 30A is provided between the slide die 7 and the co-rotating holder 23A. The rotation direction regulating mechanism 30A is configured as follows. In the holder hole 22A of the slide mold 7, a locking claw storage hole 31A having a predetermined depth is formed radially outward on an inner peripheral surface thereof. An elastic body, that is, a spring 33A is inserted into the locking claw storage hole 31A, and the locking claw 34A is stored so as to be urged by the elastic body. A claw hole 35A is formed on the outer peripheral surface of the co-rotating holder 23A so as to correspond to the locking claw 34A, and the tip of the locking claw 34A is inserted into the claw hole 35A. By the way, as shown in FIG. 2A, both the distal end portion of the locking claw 34A and the claw hole 35A are asymmetrical and inclined only to one side. Since the spring 33A is relatively weak, when a torque in the direction of reference numeral 37 is applied to the co-rotating holder 23A, the locking claw 34A retreats and the co-rotating holder 23A rotates easily. However, when a torque in the direction of reference numeral 38 acts on the co-rotating holder 23A, the locking claw 34A is locked in the claw hole 35A, so that the co-rotating holder 23A cannot rotate. That is, the rotation direction regulating mechanism 30A is a mechanism that regulates the rotation direction of the co-rotating holder 23A in one direction.

  A predetermined torque limiter 38A is provided between the co-rotating holder 23A and the rotation shaft 26A of the first core 16A. The torque limiter 38A is configured as follows. The central hole 25A of the co-rotating holder 23A is provided with a ball hole 39A having a predetermined depth radially outward from the inner peripheral surface thereof. An elastic body, that is, a spring 40A and a metal ball 42A are placed in the ball hole 39A. A depression 43A is formed on the outer peripheral surface of the rotating shaft 26A so as to correspond to the metal ball 42A. The metal ball 42A is pressed against the depression 43A by the bias of the spring. Therefore, when a torque acts between the first core 16A and the co-rotating holder 23A, the first core 16A does not idle with respect to the co-rotating holder 23A if the torque is less than a predetermined torque, but exceeds the predetermined torque. And it comes to idle. Incidentally, the predetermined torque is considerably larger than the torque required when rotating the co-rotating holder 23A in the direction of the reference numeral 37 against the rotation direction regulating mechanism 30A. Therefore, when the torque in the direction of arrow Y2 acts on the first core 16A, the co-rotating holder 23A rotates in the direction of reference numeral 37 integrally with the first core 16A.

  Such a co-rotating holder 23A is provided with a mechanism for releasing the molded two-color molded product. The co-rotating holder 23A is formed with a plate storage portion 45A having a predetermined depth that is concentrically enlarged with the center hole 25A, and the plate storage portion 45A stores an extrusion plate 46A having a donut-shaped top surface. , Spring 47A. When the molding die 1 is closed, a part of the fixed die 5 comes into contact with the extrusion plate 46A, so that the extrusion plate 46A is pushed in and the head of the first core 16A is exposed. I have.

  A method for molding a two-color molded article having a female screw using the molding die 1 according to the present embodiment will be described. With the molding die 1 opened, the piston / cylinder unit 21 is driven to slide the slide die 7 to the first position as shown in FIG. When sliding, the first and second cores 16A and 16B are rotated by the first and second racks 18A and 18B and the pinions 28A and 28B, but the first and second racks 18A and 18B are provided in opposite directions. Therefore, the first and second cores 16A and 16B rotate in directions opposite to each other. When the slide die 7 stops at the first position, the first and second cores 16A and 16B accurately reach predetermined rotation positions and stop. The first core 16A faces the primary molding recess 9. That is, it is the primary molding position. The second core 16B faces the first secondary molding recess 10. That is, it is the secondary molding position. The molding die 1 is clamped as shown in FIG. Then, the primary molding cavity 50 is formed by the first core 16A and the primary molding recess 9. The first resin is injected from the first injection device 13. Then, as shown in FIG. 3C, a primary molded article 51 having an internal thread is formed. After cooling and solidification, the molding die 1 is opened as shown in FIG. When the mold is opened, the primary molded product 51 remains on the first core 16A.

  As shown in FIG. 4A, the piston / cylinder unit 21 is driven to slide the slide mold 7 to the second position. When sliding, the first and second cores 16A and 16B rotate in directions opposite to each other, but the first core 16A rotates in the direction of arrow Y2 in FIG. At this time, the locking claw 34A of the rotation direction regulating mechanism 30A retreats, and the co-rotating holder 23A rotates integrally with the first core 16A. The end face of the primary molded product 51 is in contact with the co-rotating holder 23A, but since the co-rotating holder 23A rotates integrally with the core 16A, the primary molded product 51 also rotates integrally therewith. On the other hand, the second core 16B stops at a predetermined rotational position with high accuracy. As shown in FIG. 4A, the first core 16A is aligned with the second secondary molding recess 11. That is, it is the secondary molding position. The second core 16B is aligned with the primary molding recess 9. That is, it is the primary molding position. When the molding die 1 is clamped, as shown in FIG. 4A, a primary molding cavity 50 is formed by the second core 16B and the primary molding concave portion 9, and the primary molding cavity 50 is formed. The molded product 51 and the second secondary molding concave portion 11 constitute a secondary molding cavity 52. The first resin is injected from the first injection device 13, and the second resin is injected from the second injection device 14. As shown in FIG. 4C, the first resin is injected into the primary molding cavity 50 to form the primary molded product 51. The second resin is injected into the secondary molding cavity 52, whereby a two-color molded article 53 made of the first and second resins is molded. After cooling and solidification, the molding die 1 is opened as shown in FIG. The two-color molded product 53 remains on the first core 16A, and the primary molded product 51 remains on the second core 16B.

  As shown in FIG. 5A, the piston / cylinder unit 21 is driven to slide the slide mold 7 to the first position. When sliding, the first core 16A is rotated by the first rack 18A and the pinion 28A in the direction of the arrow Y1 shown in FIG. Then, the rotation of the co-rotating holder 23A is regulated by the rotation direction regulating mechanism 30A, and only the first core 16A rotates in the direction of the arrow Y1. Since the end face of the two-color molded product 53 is in contact with the extrusion plate 46A, the two-color molded product 53 does not rotate. Then, the male screw formed on the first core 16A rotates in the unthreading direction with respect to the female screw formed on the two-color molded product. As the screw is removed, the two-color molded product 53 is pushed forward by the extrusion plate 46A. Thereby, the two-color molded product 53 is released. On the other hand, the second core 16B is rotated by the second rack 18B and the pinion 28B in the direction of the arrow Y2 shown in FIG. Since FIG. 2A shows the first core 16A, replacing the “A” at the end of each code with “B” indicates the second core 16B. Since the second core 16B rotates in the arrow Y2 direction, the locking claw 34B of the rotation direction regulating mechanism 30B retreats, and the co-rotating holder 23B rotates integrally with the second core 16B. Therefore, the primary molded product 51 is not released.

  When the slide die 7 is at the first position, the first core 16A is at the primary molding position and the second core 16B is at the secondary molding position. The molding die 1 is clamped as shown in FIG. The first core 16A and the primary molding recess 9 constitute a primary molding cavity 50, and the primary molded product 51 and the first secondary molding recess 10 constitute a secondary molding cavity 52. You. When the first and second resins are injected from the first and second injection devices 13 and 14, a primary molded product 51 and a two-color molded product 53 are formed. After cooling and solidification, the mold is opened as shown in FIG. The primary molded product 51 and the two-color molded product 53 remain on the first and second cores 16A and 16B, respectively. The slide mold 7 is slid to the second position as shown in FIG. When sliding, the first core 16A is rotated by the first rack 18A and the pinion 28A in the direction of the arrow Y2 shown in FIG. Then, the first core 16A, the co-rotating holder 23A and the primary molded product 51 rotate integrally, and the primary molded product 51 is not released. On the other hand, the second core 16B is rotated by the second rack 18B and the pinion 28B in the direction of the arrow Y1 shown in FIG. Then, rotation of the co-rotating holder 23B is restricted, and only the second core 16B rotates. Since this rotation direction is the direction of unthreading, the two-color molded product 53 is unthreaded, extruded by the extrusion plate 46B, and demolded. Hereinafter, molding is performed in the same manner.

  The molding die 1 according to the present embodiment can be variously deformed. For example, although the first and second cores 16A and 16B have been described as being provided in the slide mold 7, only the first core 16A may be provided. The stationary mold is provided with only the primary molding recess 9 and the second secondary molding recess 11. When the slide die 7 is slid, a first molding cavity is formed by the first core 16A and the first molding recess 9, and a first molded product is obtained by injecting the first resin. When the mold is opened and the slide mold 7 is slid, the first core 16 </ b> A is at the secondary molding position where it is aligned with the second secondary molding recess 11. The mold is clamped and the second resin is injected to obtain a two-color molded product. When the mold is opened and the slide mold 7 is slid, the two-color molded product is released. Such molding is repeated. Other modifications are also possible. For example, the slide mold 7 may be provided with four or more cores. The plurality of cores are divided into a first group and a second group. When the slide die 7 is slid to the first position, the first group of cores is at the primary molding position, and the second group of cores is at the secondary molding position. Set to the molding position. Then, sliding to the second position causes the first group of cores to be at the secondary molding position and the second group of cores to be at the primary molding position. In this manner, a plurality of two-color molded articles can be molded for each molding.

  The rotation direction regulating mechanism 30A and the torque limiter 38A can also be modified. FIG. 6 shows an embodiment in which a second rotation direction regulating mechanism 30A 'is provided between the co-rotating holder 23A and the rotation shaft 26A of the first core 16A instead of the torque limiter 38A. . The second locking claw 34A 'of the second rotation direction restricting mechanism 30A' is provided with a locking claw 34A of the rotation direction restricting mechanism 30A provided between the holder hole 22A and the co-rotating holder 23A, and a distal end thereof. The shape is upside down. As will be easily understood by those skilled in the art, when a torque in the direction of arrow Y1 acts on the first core 16A, the co-rotating holder 23A stops and only the first core 16A rotates. When the torque in the direction of the arrow Y2 acts, the co-rotating holder 23A and the first core 16A rotate integrally. That is, the first core 16A performs the same operation as the molding die 1 according to the present embodiment described above.

DESCRIPTION OF SYMBOLS 1 Molding die 2 Injection molding machine 3 Fixed platen 5 Fixed die 6 Movable die 7 Slide die 9 Primary molding concave part 10 First secondary molding concave part 11 Second secondary molding concave part 13 1 injection device 14 second injection device 16A, 16B first and second cores 18A, 18B first and second rack 21 piston / cylinder unit 22A holder hole 23A co-rotating holder 25A center hole 26A rotating shaft 28A, 28B pinion 30A Rotational direction regulating mechanism 31A Locking claw storage hole 34A Locking claw 35A Claw hole 38A Torque limiter 39A Ball hole 42A Metal ball 43A recess 45A Plate storage portion 46A Extruded plate 50 Primary molding cavity 51 Primary molded product 52 2 Next molding cavity 53 Two-color molded product

Claims (5)

A fixed mold, a movable mold that is opened and closed with respect to the fixed mold, and a slide mold that is slid on the movable mold, wherein a core is rotatably provided on the slide mold. , The head of the core is exposed from the slide mold and a male screw is formed on the head,
When the slide mold is slid and the core is clamped at the primary molding position, a cavity for primary molding including the head of the core as a part thereof is formed, and the cavity for primary molding is formed. When the first resin is injected, a primary molded product is molded. The mold is opened while leaving the primary molded product in the core, and the slide mold is slid to move the core to a secondary molding position. When the mold is clamped, a cavity for secondary molding including the primary molded product as a part thereof is formed, and when the second resin is injected into the cavity for secondary molding, a two-color molded product is molded. A molding die, wherein the two-color molded product is released from the mold when the core is opened and the core is rotated in the unthreading direction,
A predetermined holder hole is formed in the slide mold, and a co-rotating holder is housed in the holder hole. The core of the core is inserted through a center hole formed in the co-rotating holder to form the slide die. Penetrates the mold,
A pinion is provided at the rear end of the rotating shaft, and a rack that meshes with the pinion is provided at the movable mold. The slide mold slides to move the core from the primary molding position to the secondary molding. When moving to the position, the core rotates integrally with the co-rotating holder, and when the core moves from the secondary molding position to the primary molding position, the co-rotating holder rotates with respect to the holder hole. A molding die for a two-color molded product having female threads, wherein the two-color molded product is released from the core only by being regulated, whereby the two-color molded product is released.   The molding die according to claim 1, wherein the co-rotating holder is provided with a spring-biased extrusion plate, and the extrusion plate is pushed by the fixed die when the molding die is clamped. The two-color molded article is opened with the two-color molded article remaining on the core, and the two-color molded article is extruded by the extrusion plate when only the core is rotated in the unthreading direction. A molding die for forming a two-color molded product on which a female screw is formed.   3. The molding die according to claim 1, wherein a torque limiter is provided between the co-rotating holder and the rotation shaft of the core, the torque limiter being idle when a predetermined torque or more is applied, and the torque limiter includes: A ball hole drilled radially outward at a predetermined depth on an inner peripheral surface of the center hole of the co-rotating holder, a metal ball housed in the ball hole, and the rotating shaft of the core; Wherein the metal ball is pressed against the depression by the bias of a spring, and a metal screw is formed on the two-color molded product. Type.   4. The molding die according to claim 1, wherein a rotation direction restriction mechanism that restricts a rotation direction of the counter-rotating holder is provided between the slide die and the counter-rotation holder, and the rotation direction restriction mechanism is provided. 5. A locking claw receiving hole formed at a predetermined depth in an inner peripheral surface of the holder hole, a predetermined locking claw stored in the locking claw storing hole, and an outer peripheral surface of the co-rotating holder. The tip of the locking claw is pressed against the claw hole by the bias of a spring, and when a torque in one rotational direction acts on the co-rotating holder, the locking claw is formed. Is pushed up from the claw hole, the locking state of the locking claw and the claw hole is released, and the co-rotating holder rotates. When torque in the opposite direction is applied, the locking claw is locked in the claw hole. State is maintained and the rotation of the co-rotating holder is regulated. Characterized in that it is so, the molding die for two-color molded article female screw is formed. 5. The molding die according to claim 1, wherein the slide die is provided with two or more sets of the core and the co-rotating holder. The first and second groups are divided into a first group and a second group. When the slide die is set at a predetermined slide position, the core of the first group is at a primary molding position and the core of the second group is at a secondary molding position. And the other group of slide positions, the first group of the cores is in the secondary molding position and the second group of the cores is in the primary molding position, characterized in that the two colors with female threads Mold for molding of molded products.

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