JP2009018450A - Injection molding die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection molding die, wherein even in the case of a type of allowing core insert pins to be engaged with each other for forming an undercut shape, external power is not required. <P>SOLUTION: Two movement units 80, 180 move accompanying the opening/closing of an injection molding die 30, and, by this movement, the core insert pins 20 and 120 are put in/out from a molding space 34 in such a manner that they are not interfered with each other. In such a state that the injection molding die 30 is perfectly opened, i.e., in such a state that a fixed side insert 42 and a movable side insert 62 are perfectly separated, and the fixed side movement unit 50 and the movable side movement unit 70 are not in contact with each other at all and further a fixed side movement unit 150 and a movable side movement unit 170 are not in contact with each other at all as shown in Fig.1 (and not shown here) and Fig.4, the two core insert pins 20, 120 are perfectly separated (put out) from the molding space 34 as shown in Fig.7(a). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an injection mold for injecting resin or the like into a closed mold and molding the resin into a predetermined shape.

  An injection mold composed of two molds (partial molds) that are opened and closed is widely used. Parting surfaces (surfaces forming the outer surface of the molded product) are formed on the two molds of this injection mold. After the molded product formed between the parting surfaces is cooled and solidified, the parting surface is opened (two partial molds are opened), and is taken out from the injection mold.

  In an injection mold, normally, a fixed mold and a movable mold positioned so as to sandwich two parting surfaces facing each other are closed, and a resin or the like is formed in a space (outer space) formed by these two molds. To produce a molded product. However, some molded products have a so-called undercut shape in which a space is formed. An example of a molded product having an undercut shape will be described with reference to FIG. 12 (a) is a perspective view showing an example of a molded product having an undercut shape, and FIG. 12 (b) is a molded product shown in (a) and a member (core) inserted into the internal space at the time of injection molding. It is a perspective view which shows a nesting pin.

  An example of the molded product 10 having an undercut shape is a cylinder having an L-shaped outer shape, in which a space 12 is formed. Since the molded product 10 in which such a space 12 is formed cannot be molded only from the fixed side mold and the movable side mold, the resin or the like is placed in a state where the core nesting pins 14 and 16 are arranged in the portion corresponding to the space 12. It is injected. When an undercut shaped product is injection molded as described above, a slide mechanism is used to process the undercut shape (to move the core nesting pin). As is well known, there are various types of slide mechanisms, such as a fixed side slide, a movable side slide, an inner diameter slide, and an inclined core method. In general, except for the inclined core, the timing at which the slide operation starts is simultaneous with the mold opening. In order to change the timing at which the core nesting pin starts moving not simultaneously with the mold opening, the slide is moved using external power such as electric power or hydraulic pressure (for example, see Patent Document 1).

However, in the case of a mold having a structure in which the core nesting pin is moved using external power such as an electric cylinder or a hydraulic cylinder as in the conventional case, the structure becomes complicated and the size is increased, resulting in an increase in cost. Therefore, a technique is provided in which a secondary slide core that moves in different directions is provided in the slide core to which the core nesting pin is fixed, and the length of the angular pin that controls the secondary slide is shortened (for example, see Patent Document 2). A technique (for example, refer to Patent Document 3) in which an angular pin hole formed in a slide core has an elliptical shape with a major axis in the moving direction of the slide core has been proposed. According to these techniques, a time difference can be given to the movement of the slide core without using external power such as a hydraulic cylinder.
Japanese Patent Laid-Open No. 7-16884 JP-A-11-19976 JP-A-8-281726

  However, in the above technique, the slide core returns to the initial position at the same time as the mold is closed. Therefore, in the mold having a structure that combines the slide cores, for example, in the core nest attached to one slide core, the other Cannot be used when inserting a core insert attached to a slide core. This is because the core inserts collide with each other and are damaged when the mold is closed.

  By the way, in order to injection-mold a molded product having an L-shaped space (flow path) as shown in FIG. 12, two core nesting pins 18 and a core nesting pin are used as shown in FIG. A method is conceivable in which 19 is abutted on the surface. When the two core nesting pins 18 and 19 are brought into contact with each other as described above, the core nesting pins 18 and 193 may be moved by the pressure of the resin during the injection molding. When the two core nesting pins 18 and 19 move during injection molding, burrs are generated in the space (in the flow path), and the quality of the obtained molded product may not be stable.

  Therefore, as shown in FIG. 14, a recess is formed in one of the two core nesting pins 20 and 120 (in FIG. 14, a recess is formed at the tip of the core nesting pin 120). A technique is conceivable in which the other end portion is fitted and the flow path shape is reliably obtained. However, in this technique, the core nesting pin 20 must be moved (faster) before the core nesting pin 120 when the mold is opened. Further, when closing the mold, the core nesting pin 120 must be moved (faster) than the core nesting pin 20. Thus, in order to move the two core nesting pins 20 and 120 at different timings when the mold is opened and closed, a technique using external power can be considered. However, in this technology using external power, as described above, the structure becomes complicated and the size and cost are increased.

  Further, the length of the angular pin that moves the slide core is made shorter than the angular pin that moves the core nesting pin 120 so that the core nesting pin 20 moves before the core nesting pin 120 when the mold is opened (see the above patent). Even if the angular pin hole vacated in the slide core is made elliptical so that the major axis is in the moving direction of the slide core (see Patent Document 3 above), Since the slide core tries to return to the initial position at the same timing, the core nesting pins 20 and 120 collide and bend.

  In view of the above circumstances, an object of the present invention is to provide an injection mold that does not require external power even if it is a type in which core nesting pins are fitted together to form an undercut shape.

In order to achieve the above object, an injection mold according to the present invention includes a stationary nesting and a movable nesting that form an outer space that forms an outer shape of a molded product by being closed and in contact with each other. And at least two core nesting pins that are taken in and out of the outer space, and one core nesting pin of the at least two core nesting pins fits a tip portion of the other core nesting pin. An injection molding in which a molded product is injection-molded in a state in which the tip of the other core nesting pin is fitted in the recess of the one core nesting pin in the outer space. In the mold,
(1) The one core nesting pin and the other one so that the one core nesting pin and the other one core nesting pin do not interfere with each other when the fixed side nesting and the movable side nesting are opened and closed. The core nesting pin is moved, and a moving unit incorporated therein is provided.

Here, the mobile unit is
(2) When the movable unit is opened from a state where the fixed side insert and the movable side insert are closed, the moving unit moves the other one core insert pin in a direction to be taken out from the outer space. The two core nesting pins are moved so as to move the one core nesting pin in a direction to be taken out of the outer space after the tip portion is extracted from the recess of the one core nesting pin. When the fixed side insert and the movable side insert are closed from the opened state, after inserting the one core insert pin into the outer space, the tip of the other core insert pin is The two core nesting pins may be moved so as to be fitted into the recesses of the one core nesting pin.

The mobile unit is
(3) When the fixed side nest and the movable side nest are opened from the closed state, the tip of the other core nest pin is extracted from the recess of the one core nest pin. The one core nesting pin is stopped until the fixed side nesting and the movable side nesting are closed from the opened state until the one core nesting pin enters the outer space. The tip of the other single core nesting pin may not be fitted into the recess of the single core nesting pin.

Further, the mobile unit is
(4) When the fixed side insert and the movable side insert are opened from a closed state, the tip of the other core insert pin is extracted from the recess of the one core insert pin. A biasing member that biases the single core nesting pin so as to keep the single core nesting pin positioned in the external space may be provided.

Furthermore,
(5) A slide core that moves in the longitudinal direction of the one core nesting pin and to which the one core nesting pin is fixed,
(6) The biasing member may bias the slide core in the closing direction.

Furthermore,
(7) A slide core that moves in the longitudinal direction of the one core nesting pin and to which the one core nesting pin is fixed,
(8) The biasing member may bias the slide core toward the tip of the one core insert pin.

Furthermore,
(9) The biasing member may be a coil spring.

  In the injection mold of the present invention, one core nesting pin and one other core nesting pin and the other one so that the one core nesting pin and the other core nesting pin do not interfere with each other when the fixed side nesting and the movable side nesting are opened and closed Since the moving unit that moves the core nesting pin is built in, external power is not required even if the core nesting pin is fitted to form an undercut shape, and the mold configuration is complicated Increase in size, size, and price.

  The present invention has been realized in an injection mold of a type in which core nesting pins are fitted to form an undercut shape.

  A first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a cross-sectional view showing a moving unit that moves the other core nesting pin having a tip portion that fits into the recess of one core nesting pin, and shows a state when the injection mold is opened. FIG. 2 is a cross-sectional view showing the moving unit when the injection mold is closed and approaches the distance S from the state of FIG. FIG. 3 is a sectional view showing the moving unit when the injection mold is completely closed from the state of FIG. 4 is a cross-sectional view showing a moving unit that moves one core nesting pin in which a recess into which the tip of the other core nesting pin fits is formed, and the entire injection mold is in the same state as FIG. At the time. FIG. 5 is a cross-sectional view showing the moving unit when the injection mold is closed and approaches the distance S from the state shown in FIG. 4, and the entire injection mold is in the same state as FIG. FIG. 6 is a cross-sectional view showing the moving unit when the injection mold is completely closed from the state of FIG. 5, and the entire injection mold is in the same state as FIG. FIG. 7 is a partially enlarged view showing the positions of one and the other core nesting pins. FIG. 7A shows a state where both the one and the other core nesting pins are out of the outer space. 4, (b) shows a state in which only one core nesting pin reaches a predetermined position in the outer space and the other core nesting pin does not reach a predetermined position in the outer space. Corresponding to FIG. 5, (c) shows a state in which both the one and the other core nesting pins have reached a predetermined position in the outer space, and corresponds to FIG. 3 and FIG. 1 to 3 show the injection mold 30 viewed from the direction of arrow R in FIG. 7, and FIGS. 4 to 6 show the injection mold 30 viewed from the direction of arrow L in FIG. Is.

  The injection mold 30 includes a fixed mold 40 that is fixed and does not move, and a movable mold 60 that moves in the direction of arrow A and in the opposite direction. The fixed mold 40 is provided with a fixed-side insert 42 in which the upper half of the outer space 34 that forms the outer shape of the molded product 10 is formed (carved). The fixed side insert 42 is fixed to a fixed side mold plate 44 that is a base of the fixed mold 40. On the other hand, the movable mold 60 is provided with a movable side insert 62 in which the lower half of the outer space 34 that forms the outer shape of the molded product 10 is formed (engraved). The movable side insert 62 is fixed to a movable side mold plate 64 that is a base of the movable mold 60. Moving units 80 and 180, which will be described later, are incorporated in the fixed side mold plate 44 and the movable side mold plate 64.

  The injection mold 30 also includes core insert pins 20 and 120 as shown in FIG. 7, and the injection mold 30, for example, has an L-shaped flow path 12 inside as shown in FIG. 12. An L-shaped molded product formed with is formed. The injection mold 30 has two moving units 80 and 180 that independently move (control) the two core nesting pins 20 and 120 so that the two core nesting pins 20 and 120 do not interfere with each other. Is built inside. The moving unit 80 is for moving the core nesting pin 20, and the moving unit 180 is for moving the core nesting pin 120. According to the two moving units 80 and 180, the injection mold 30 is completely opened as shown in FIGS. 3 and 6 from the state where the injection mold 30 is completely opened as shown in FIGS. When shifting to the closed state (when the mold is opened), the core nesting pin 120 reaches a predetermined position in the outer space 34 before the core nesting pin 20, and the core nesting pin 20 is formed after the core nesting pin 120. A predetermined position in the space 34 is reached. On the contrary, when the injection mold 30 is completely closed as shown in FIGS. 3 and 6, the injection mold 30 is completely opened as shown in FIGS. 1 and 4. (When the mold is closed), the core nesting pin 20 is disengaged from the predetermined position in the outer space 34 before the core nesting pin 120, and the core nesting pin 120 is disengaged from the predetermined position in the outer space 34 after the core nesting pin 20. .

  First, the structure of the moving unit 80 that moves the core nesting pin 20 will be described.

  The moving unit 80 is roughly divided into a fixed side moving unit 50 incorporated in the fixed side template 44 and a movable side moving unit 70 incorporated in the movable side template 64. When the injection mold 30 is opened and closed, the fixed side moving unit 50 and the movable side moving unit 70 cooperate to move the core nesting pin 20 in the arrow B direction and in the opposite direction. The fixed-side moving unit 50 is located on the downstream side (right side in FIGS. 1 to 3) in the arrow B direction (the direction in which the core nesting pin 20 is extracted from the outer space 34) of the fixed-side template 44 with respect to the fixed-side insert 42. The locking block 52 is fixed, an angular pin 54 is fixed to the locking block 52, and a contact surface 56 of the locking block. The angular pin 54 has a cylindrical shape that is inclined with respect to the moving direction of the movable mold 60 (the direction of arrow A and the opposite direction), and the inclination angle is an angle θ (inclination angle) with respect to the arrow A direction. θ) and directed downstream in the direction of arrow B. The contact surface 56 of the locking block is also inclined by an angle θ + 2 ° with respect to the moving direction of the movable mold 60 and is directed downstream in the direction of arrow B. The inclination angle and the inclination direction of the angular pin 54 and the contact surface 56 of the locking block are the same.

  The locking block 52 and the angular pin 54 move relative to the movable side moving unit 70. In order to make the drawing easier to see, the angular pin 54 is not hatched.

  The movable side moving unit 70 is fixed (or arranged) to the rear end side (downstream side in the arrow B direction) of the core insert pin 20. The tip (portion) of the core nesting pin 20 refers to a portion that enters and exits the outer space 34, and the side opposite to the tip in the longitudinal direction of the core nesting pin 20 is referred to as the rear end (portion). Is the same. A rear end plate 20 a extending in the arrow A direction is formed at the rear end of the core insert pin 20, and a downstream portion (surface) in the arrow B direction of the rear end plate 20 a is fixed to the slide core 72. ing. The rear end plate 20a formed integrally with the core insert pin 20 is fixed to the slide core 72 and moves together with the slide core 72 as will be described later. The slide core 72 is attached to the upper surface of the movable mold plate 64 via a guide rail (not shown) so that the upper surface of the movable mold plate 64 can be freely moved (slided) in the direction of arrow B and in the opposite direction. It has been. A portion of the slide core 72 opposite to the rear end plate 20a is formed with a surface 72a that is inclined by an angle θ + 2 ° with respect to the direction of the arrow A. The surface 72a has a thin rectangular parallelepiped slide plate. 76 is fixed. At the time of mold clamping (the state shown in FIG. 3), the slide core 72 is clamped by the contact surface 56 of the locking block and the slide plate 76 contacting each other.

  An angular hole 74 through which the angular pin 54 enters and exits as the injection mold 30 opens and closes is formed in the lower part of the slide core 72 in the direction of the arrow B slightly downstream of the slide plate 76. The angular hole 74 penetrates from the upper surface to the lower surface of the slide core 72 and forms an angle θ (inclination angle θ) with respect to the direction of the arrow A so that the angular pin 54 can smoothly enter and exit. Further, as shown in FIGS. 2 and 3, an escape hole 64 a into which the lower end portion of the angular pin 54 enters is formed in a portion connected to the angular hole 74 on the upper surface of the movable side mold plate 64.

  A screw portion (tip portion) 78a of a bolt 78 extending in the arrow B direction (its longitudinal direction coincides with the arrow B direction) is fixed (screwed in) to the most downstream portion of the slide core 72 in the arrow B direction. ) A central portion 78b in the longitudinal direction of the bolt 78 passes through a plate-like slide stopper 79 fixed to the side surface 64b of the movable side mold plate 64. A screw 78 is not formed on the longitudinal center portion 78b of the bolt 78 and has a smooth surface. The longitudinal center portion 78b can smoothly move through the through hole 79a of the slide stopper 79. A central portion 78b of the bolt 78 in the longitudinal direction is inserted into the coil spring 77, one end of the coil spring 77 is in contact with the side surface 79b of the slide stopper 79, and the other end is in contact with the lower surface of the head 78c of the bolt 78. . Accordingly, the slide core 72 is always urged in the direction of arrow B by the coil spring 77. In order to make the drawing easy to see, the bolt 78 and the coil spring 77 are not hatched.

  The structure of the moving unit 180 that moves the core nesting pin 120 will be described.

The moving unit 180 is roughly divided into a fixed side moving unit 150 incorporated in the fixed side template 44 and a movable side moving unit 170 incorporated in the movable side template 64. When the injection mold 30 is opened and closed, the fixed side moving unit 150 and the movable side moving unit 170 cooperate to move the core nesting pin 120 in the direction of arrow C and in the opposite direction. The fixed-side moving unit 150 is located on the downstream side (the right side in FIGS. 4 to 6) of the fixed-side template 44 in the direction of arrow C (the direction in which the core nesting pin 120 is extracted from the outer space 34) from the fixed-side insert 42. The locking block 152 is arranged, and the angular pin 154 is fixed to the locking block 152. The angular pin 154 has a cylindrical shape that is inclined and extends with respect to the moving direction of the movable mold 60 (the direction of arrow A and the opposite direction). θ) and directed downstream in the direction of arrow C. The contact surface 156 of the locking block is also inclined by about an angle θ + 2 ° with respect to the moving direction of the movable mold 60 and is directed downstream in the direction of arrow C. The inclination directions of the angular pin 154 and the contact surface 156 of the locking block are the same. Moreover, the value of this inclination angle (theta) is the same as the value of inclination angle (theta) in FIGS.
The locking block 152 and the angular pin 154 move relative to the movable side moving unit 170. In order to make the drawing easier to see, the angular pins 154 are not shaded.

  A downward opening (facing in the direction of arrow A) is provided in the downstream side portion of the fixed side template 44 in the direction of arrow C from the fixed side insert 42 (the right side portion of the fixed side insert 42 in FIGS. 4 to 6). A concave portion 44a is formed. A bolt 158 is inserted into the recess 44a from above through the wall 44b. A front end portion of the bolt 158 (a screw portion on which a screw is formed, not shown) is screwed into the locking block 152. For this reason, the bolt 158 and the locking block 152 are integrated. The head portion 158a of the bolt 158 is stopped at the upper surface of the wall 44b (the head portion 158a is larger than the diameter of the through hole of the wall 44b), and a screw is formed in the longitudinal central portion 158b of the bolt 158. It is not smooth and has a smooth surface, and this longitudinal central portion 158b can smoothly move through a through hole (not shown) in the wall 44b. A central portion 158 b in the longitudinal direction of the bolt 158 is inserted into the coil spring 157. The upper end of the coil spring 157 is in contact with the bottom surface of the recess 44 a and the lower end is in contact with the upper surface of the locking block 152. Therefore, the locking block 152 is always urged in the arrow A direction by the coil spring 157. The bolts 158 and the coil springs 157 are not shaded to make the drawing easier to see.

  The locking block 152 is attached to the wall surface 44c via a guide rail (not shown) or the like so that the wall surface 44c of the recess 44a can freely move (slide) in the direction of arrow A and in the opposite direction. As will be described later, as the injection mold 30 is opened and closed, the locking block 152 moves in the direction of arrow A or in the opposite direction.

  The movable side moving unit 170 is fixed (or arranged) to the rear end side (downstream side in the direction of arrow C) of the core insert pin 120. The tip (part) of the core nesting pin 120 refers to a portion that enters and exits the outer space 34, and the side opposite to the tip in the longitudinal direction (arrow C direction) of the core nesting pin 120 is referred to as a rear end (part). A rear end plate 120a extending in the arrow A direction is formed at the rear end of the core insert pin 120, and a slide core 172 is fixed to a downstream portion (surface) of the rear end plate 120a in the arrow C direction. Has been. The rear end plate 120a formed integrally with the core insert pin 120 is fixed to the upper part of the surface upstream of the slide core 172 in the arrow C direction, and moves together with the slide core 172 as will be described later. The slide core 172 is attached to the upper surface of the movable side mold plate 64 via a guide rail (not shown) or the like so that the upper surface of the movable side mold plate 64 can freely move (slide) in the direction of arrow C and in the opposite direction. ing. A portion 172a of the slide core 172 opposite to the rear end plate 120a is formed with a surface 172a that is inclined by an angle θ + 2 ° with respect to the direction of arrow A. The surface 172a has a thin rectangular parallelepiped slide plate. 176 is fixed. When the injection mold 30 is clamped (state of FIG. 6), the slide core 172 is clamped by the contact surface 156 of the locking block and the slide plate 176 contacting each other.

  An angular hole 174 through which the angular pin 154 enters and exits as the injection mold 30 opens and closes is formed in the lower part of the slide core 172 slightly downstream in the direction of arrow C from the slide plate 176. The angular hole 174 penetrates from the upper surface to the lower surface of the slide core 172 and forms an angle θ (inclination angle θ) with respect to the arrow A direction so that the angular pin 154 can smoothly enter and exit. Further, an escape hole 64c into which the lower end portion of the angular pin 154 enters is formed in a portion of the upper surface of the movable side mold plate 64 connected to the angular hole 174 as shown in FIGS.

  A screw portion (tip portion) 178a of a bolt 178 extending in the arrow C direction (the longitudinal direction thereof coincides with the arrow C direction) is fixed (screwed in) to the most downstream portion of the slide core 172 in the arrow C direction. ) A central portion 178 b in the longitudinal direction of the bolt 178 passes through a plate-like slide stopper 179 fixed to the side surface 64 d of the movable side mold plate 64. The longitudinal center portion 178b of the bolt 178 has a smooth surface without screws, and the longitudinal center portion 178b can smoothly move through the through hole 179a of the slide stopper 179. A central portion 178b in the longitudinal direction of the bolt 178 is inserted into the coil spring 177. One end of the coil spring 177 contacts the side surface 179b of the slide stopper 179, and the other end contacts the lower surface of the head 178c of the bolt 178. . Therefore, the slide core 172 is always urged in the direction of arrow C by the coil spring 177. The bolts 178 and the coil springs 177 are not hatched for easy viewing of the figure.

  The operation of the two moving units 80 and 180 will be described.

  As the injection mold 30 is opened and closed, the two moving units 80 and 180 are moved. By this movement, the core insert pin 20 and the core insert pin 120 are inserted and removed from the forming space 34 without interfering with each other. In a state where the injection mold 30 is completely opened, that is, as shown in FIGS. 1 and 4, the fixed side insert 42 and the movable side insert 62 are completely separated, and the fixed side moving unit 50 and the movable side moving unit 70 are completely separated. In a state where the stationary side moving unit 150 and the movable side moving unit 170 are not in contact at all, the two core nesting pins 20 and 120 are removed from the molding space 32 as shown in FIG. They are completely separated (out).

  When the injection mold 30 starts to close from the state shown in FIGS. 1 and 4 (the movable side insert 62 starts to move in the direction opposite to the direction of the arrow A together with the movable side mold 64), the angular pin 154 first. The distal end portion 154a of the pin 154 reaches the angular hole 174 and begins to be inserted, and the outer peripheral surface of the angular pin 154 comes into contact with the inner peripheral surface of the angular hole 174 to resist the biasing force of the coil spring 177 and the arrow C Start moving in the opposite direction. At this time, as shown in FIG. 1, the angular pin 54 of the moving unit 80 does not reach the angular hole 74. Thus, the reason why the angular pin 154 reaches (inserts) the angular pin 174 before the angular pin 54 reaches (inserts) the angular hole 74 is that the angular pin 154 of the moving unit 180 is fixed. This is because it is moved in the direction of arrow A by the spring 157 together with the locking block 152.

  When the injection mold 30 is further closed (the movable side nest 62 is further moved in the direction opposite to the arrow A direction together with the movable side mold 64), as shown in FIGS. 2 and 5, the fixed side nest 42 and The movable side nest 62 approaches the distance S. Until the fixed side insert 42 and the movable side insert 62 approach each other by the distance S, the angular pin 154 of the moving unit 180 is inserted deeper into the angular hole 174, and the outer periphery of the angular pin 154 extends along the inner periphery of the angular hole 174. While sliding, the slide core 172 is moved in the direction opposite to the arrow C direction against the urging force of the coil spring 177. When the fixed side insert 42 and the movable side insert 62 are close to each other by the distance S, the angular pin 154 of the moving unit 180 has been completely inserted into the angular hole 174, and the slide core 172 is in a direction opposite to the arrow C direction. After moving, the movable side insert 62 is in contact (contact). For this reason, as shown in FIG. 7B, the core nesting pin 120 has a predetermined position in the molding space 34 (a position where the tip of the core nesting pin 120 approaches the wall of the molding space 34 to form a flow path of the molded product. ).

  On the other hand, until the fixed side insert 42 and the movable side insert 62 approach each other by the distance S, the angular pin 54 of the moving unit 80 starts to be inserted into the angular hole 74, and the outer periphery of the angular pin 54 extends the inner periphery of the angular hole 74. While sliding, the slide core 72 is moved in the direction opposite to the arrow B direction against the urging force of the coil spring 77. When the fixed side insert 42 and the movable side insert 62 are close to each other by the distance S, the angular pin 54 of the moving unit 80 is inserted into the angular hole 74, but the slide core 72 is in the direction of arrow B as shown in FIG. Has not finished moving in the opposite direction, and is not in contact (not in contact) with the movable-side insert 42. For this reason, as shown in FIG. 7B, the core nesting pin 20 is in the middle of reaching the molding space 34, and the predetermined position (the tip of the core nesting pin 20 fits into the recess of the core nesting pin 120). It has not reached the position where it gets stuck. Therefore, when closing the injection mold 30 in the open state, the core nesting pin 120 reaches a predetermined position before the core nesting pin 20, so that the two core nesting pins 20, 120 do not interfere with each other. There is no inadvertent collision.

  When the injection mold 30 is further closed from the above state (the movable side mold plate 64 is further moved in the direction opposite to the arrow A direction), as shown in FIG. The movable side nest 62 contacts the fixed side nest 42 by moving in the direction opposite to the direction of the arrow A against the urging force.

  On the other hand, in the moving unit 80, as shown in FIG. 3, the outer periphery of the angular pin 54 slides on the inner periphery of the angular hole 74 and moves the slide core 72 in the direction of arrow B against the urging force of the coil spring 77. It is moved in the opposite direction and brought into contact with the movable side insert 62. In this state, as shown in FIG. 7C, the tip of the core insert pin 20 is fitted into the recess of the core insert pin 120, and both the pins 20 and 120 have reached a predetermined position. That is, as shown in FIGS. 3 and 6, the fixed side insert 42 and the movable side insert 62 come into contact with each other and the injection mold 30 is completely closed.

  As described above, when the injection mold 30 is closed, the two core nesting pins 20 and 120 can prevent collision without interfering with each other. The lengths and the inclination angles θ of the angular pins 54 and 154 are determined so as not to completely come out of the molded product 10 when the mold is opened (the state shown in FIGS. 1 and 4) and do not interfere with the molded product 10.

  As shown in FIGS. 3 and 6, the resin or the like is injected into the molding space 34 after the injection mold 30 is completely closed. Thereby, as shown in FIG.7 (c), the molded article 10 (molded article 10 which has an undercut shape) in the state in which the core insert pin 20 and 120 entered was produced. An operation of opening the injection mold 30 and taking out the molded product 10 after the molded product 10 is manufactured will be described.

  As shown in FIGS. 6 and 3, when opening the injection mold 30 in a completely closed state, the movable side mold plate 64 is moved in the direction of arrow A. The moving unit 180 starts moving the movable side template 64 in the direction of arrow A until the fixed side nest 42 and the movable side nest 62 are separated by a distance S as shown in FIGS. Since the locking block 152 is continuously pushed in the direction of arrow A by the urging force (the urging force is continued), the angular pin 154 remains completely inserted into the angular hole 174, and the slide core 172 is inserted into the movable side nesting. 62 remains in contact. For this reason, the core nesting pin 120 is kept in the state shown in FIG. 7C (it is kept in a predetermined position).

  On the other hand, the movable unit 80 starts moving the movable side template 64 in the direction of arrow A until the fixed side nest 42 and the movable side nest 62 are separated by a distance S as shown in FIGS. 52 is fixed to the fixed side template 44, so that the outer periphery of the angular pin 54 slides on the inner periphery of the angular pin hole 74 in the direction of the arrow A as the movable side insert 62 moves in the direction of the arrow A. As a result, the angular pin 54 comes out of the angular hole 74 only a little (a distance corresponding to the distance S). For this reason, the slide core 72 is relatively separated from the movable side nest 62, whereby the core nest pin 20 is slightly removed from the molding space 34. As shown in FIG. 7 (b), the distance to be pulled out is longer than the distance at which the tip of the core insert pin 20 is extracted from the recess of the core insert pin 120.

  When opening the injection mold 30 in the completely closed state as described above, the movable side mold plate 64 starts to move in the direction of the arrow A, and the fixed side insert 42 and the movable side as shown in FIGS. Until the nest 62 is separated by the distance S, the slide core 172 of the moving unit 180 remains in contact with the movable nest 62 and does not move in the direction of the arrow C, so that the core nest pin 120 remains in a predetermined position. On the other hand, as shown in FIGS. 5 and 2, the slide core 72 of the moving unit 80 moves away from the movable side nest 62 in the direction of arrow B until the fixed side nest 42 and the movable side nest 62 are separated by a distance S. Therefore, the core nesting pin 20 is removed from the predetermined position, and the tip portion is extracted from the recess of the core nesting pin 120. Thus, in the initial stage of opening the injection mold 30 in the completely closed state (until the fixed side insert 42 and the movable side insert 62 are separated by the distance S), the core insert pin 120 moves. Without moving the core nesting pin 20. Accordingly, when the injection mold 30 is opened, the two core nesting pins 20 and 120 can be prevented from being damaged without interfering with each other.

  After the fixed side insert 42 and the movable side insert 62 are separated by a distance S, the injection molding die 30 is further opened to open the angular pin 154 from the angular hole 174 and slide in the moving unit 180 as shown in FIG. Since the force pushing the core 172 in the direction opposite to the arrow C direction is released, the sliding core 172 moves in the arrow C direction by the biasing force of the coil spring 177 and the core nesting pin 120 comes out of the molded product 10. As shown in FIG. 1, in the moving unit 80, the force that pushes the slide core 72 in the direction opposite to the arrow B direction by the angular pin 54 coming out of the angular hole 74 is released. The core 72 moves in the direction of arrow B, and the core insert pin 20 comes out of the molded product 10. As a result, the molded product 10 can be taken out from the injection mold 30.

  As described above, according to the injection mold 30 of the first embodiment, when the injection mold 30 is opened and closed (when the fixed side insert 42 and the movable side insert 62 are opened and closed), the two core insert pins 20 and 120 are provided. Since two sets of moving units 80 and 180 for independently moving the two core insert pins 20 and 120 so as not to interfere with each other are incorporated in the injection mold 30, an undercut shape is formed. Therefore, even if it is a type in which the core insert pins 20 and 120 are fitted together, external power is not required, and it is possible to suppress the complexity, increase in size, and increase in price of the mold configuration.

  A second embodiment of the present invention will be described with reference to FIGS.

  8 to 10 are cross-sectional views showing another example (Example 2) of the injection mold 30 according to the first embodiment. The injection mold 230 according to the second example is an injection mold according to the first example. The same moving unit 80 as that of the mold 30 is provided, and the structure of the moving unit 180 is different between the first embodiment and the second embodiment. Therefore, another example of the moving unit 180 will be described.

  FIG. 8 is a cross-sectional view showing a moving unit that moves one core nesting pin in which a recess into which the tip of the other core nesting pin fits is formed, and the entire injection mold is in the same state as FIG. At the time. FIG. 9 is a cross-sectional view showing the moving unit when the injection mold is closed and approaches the distance S from the state of FIG. 8, and the entire injection mold is in the same state as FIG. FIG. 10 is a cross-sectional view showing the moving unit when the injection mold is completely closed from the state of FIG. 9, and the entire injection mold is in the same state as FIG. In these drawings, the same components as those shown in FIGS. 4 to 6 are denoted by the same reference numerals.

  The moving unit 280 for moving the core nesting pin 120 in the direction of arrow C and in the opposite direction includes a fixed side moving unit 250 incorporated in the fixed side template 44 and a movable side moving unit 170 incorporated in the movable side template 64. Consists of Since the movable side moving unit 170 operates in exactly the same structure as the movable side moving unit 170 of the first embodiment, the description thereof is omitted.

  When the injection mold 230 of Example 2 is opened and closed, the fixed side moving unit 250 and the movable side moving unit 170 cooperate to move the core nesting pin 120 in the direction of arrow C and in the opposite direction. The fixed-side moving unit 250 is located on the downstream side (right side in FIGS. 8 to 10) of the fixed-side template 44 in the direction of arrow C (the direction in which the core nesting pin 120 is extracted from the outer space 34) from the fixed-side insert 42. The locking block 252 is fixed, the angular pin 254 is fixed to the locking block 252, and a contact surface 256 that comes into contact with the slide plate 176 when the mold is closed. The angular pin 254 has a cylindrical shape that is inclined with respect to the moving direction of the movable die 60 (the direction of arrow A and the opposite direction), and the inclination angle is an angle θ (inclination angle) with respect to the arrow A direction. θ) and directed downstream in the direction of arrow C. The contact surface 256 of the locking block is also inclined by an angle θ + 2 ° with respect to the moving direction of the movable mold 60 and is directed downstream in the direction of arrow C.

  The locking block 252, the angular pin 254, and the locking plate 256 move relative to the movable side moving unit 170. In order to make the drawing easier to see, the angular pins 254 and the bolts 258 are not hatched.

  Of the fixed side template 44, the downstream side portion in the direction of arrow C relative to the fixed side insert 42 (the right side portion of the fixed side insert 42 in FIGS. 8 to 10) faces right (facing upstream in the arrow C direction). A recess 244a having an opening is formed. Bolts 258 are inserted into the recesses 244a through the wall 244b from the right side (from the downstream side in the direction of arrow C). A front end portion (a screw portion on which a screw is formed) 258 b of the bolt 258 is screwed into the locking block 252. For this reason, the bolt 258 and the locking block 252 are integrated. The head portion 258a of the bolt 258 stops at the right side surface of the wall 244b (the head portion 258a is larger than the diameter of the through-hole of the wall 244b), and a screw is attached to the longitudinal central portion 258c of the bolt 258. It is not formed but has a smooth surface, and the longitudinal central portion 258c can smoothly move through the through hole of the wall 244b. A central portion 258 c in the longitudinal direction of the bolt 258 is inserted into the coil spring 257, and the right end of the coil spring 257 is in contact with the bottom surface of the recess 244 a and the left end is in contact with the side surface of the locking block 252. Therefore, the locking block 252 is always urged in the direction of arrow C by the coil spring 277. The bolts 158 and the coil springs 157 are not shaded to make the drawing easier to see.

  The locking block 252 is attached to the bottom surface 244c via a guide rail (not shown) or the like so that the bottom surface 244c of the recess 244b can freely move (slide) in the direction of arrow C and in the opposite direction. As will be described later, the locking block 252 moves in the direction of arrow C or in the opposite direction as the injection mold 230 is opened and closed.

  The operation of the mobile unit 280 will be described.

  As the injection mold 230 is opened and closed, the two moving units 80 and 280 are moved, and by this movement, the core insert pin 20 and the core insert pin 120 are inserted and removed from the forming space 34 without interfering with each other. The state where the injection mold 230 is fully opened, that is, as shown in FIGS. 1 and 8, the fixed side insert 42 and the movable side insert 62 are completely separated from each other, and the fixed side moving unit 50 (see FIG. 1 etc.) and the movable side In a state where the moving unit 70 (see FIG. 1 etc.) is not in contact at all and the fixed side moving unit 250 and the movable side moving unit 170 are not in contact at all, as shown in FIG. The core nesting pins 20 and 120 are completely separated (out) from the molding space 32.

  First, the injection molding die 230 starts to close from the state shown in FIGS. 1 and 8 (the movable side insert 62 starts to move in the direction opposite to the arrow A direction together with the movable side mold 64). The distal end portion 254a of the pin 254 reaches the angular hole 174 and begins to be inserted, and the outer peripheral surface of the angular pin 254 contacts the inner peripheral surface of the angular hole 174 to resist the urging force of the coil spring 177, and the arrow C Start moving in the opposite direction. At this time, as described above, the angular pin 54 of the moving unit 80 (see FIG. 1 and the like) does not reach the angular hole 74. Thus, the reason why the angular pin 254 reaches (inserts) the angular pin 174 before the angular pin 54 reaches (inserts) the angular hole 74 is that the angular pin 254 of the moving unit 280 moves. This is because it is longer than the angular pin 54 of the unit 80, and the inclination angle θ of the two angular pins 54, 254 with respect to the direction of arrow A is equal.

  When the injection mold 230 is further closed (the movable side nest 62 moves further in the direction opposite to the arrow A direction together with the movable side mold 64), as shown in FIGS. 2 and 9, the fixed side nest 42 and The movable side nest 62 approaches the distance S. Until the fixed side insert 42 and the movable side insert 62 approach each other by the distance S, the angular pin 254 of the moving unit 280 is inserted deeper into the angular hole 174, and the outer periphery of the angular pin 254 passes through the inner periphery of the angular hole 174. While sliding, the slide core 172 is moved in the direction opposite to the arrow C direction against the urging force of the coil spring 177. In a state where the fixed side insert 42 and the movable side insert 62 are close to each other by the distance S, the angular pin 254 of the moving unit 280 has been completely inserted into the angular hole 174, and the slide core 172 is in a direction opposite to the arrow C direction. After moving, the movable side insert 62 is in contact (contact). For this reason, as shown in FIG. 7B, the core nesting pin 120 reaches a predetermined position in the molding space 34 (a position where the tip of the core nesting pin 120 hits the wall of the molding space 34).

  When the injection mold 230 is further closed from the above state (the movable side mold plate 64 is further moved in the direction opposite to the arrow A direction), the fixed side moving unit 250 is turned into the coil spring 257 as shown in FIG. The movable side nest 62 contacts the fixed side nest 42 by moving in the direction opposite to the arrow C direction against the urging force.

  As described above, when the injection mold 230 is closed, the two core nesting pins 20 and 120 can prevent collision without interfering with each other. The lengths and inclination angles θ of the angular pins 54 and 254 are determined to values that can safely come out of the molded product 10 when the mold is opened (the state shown in FIGS. 1 and 8) and do not interfere with the molded product 10.

  As shown in FIGS. 3 and 10, the resin or the like is injected into the molding space 34 after the injection mold 230 is completely closed. Thereby, as shown in FIG.7 (c), the molded article 10 (molded article 10 which has an undercut shape) in the state in which the core insert pin 20 and 120 entered was produced. An operation of opening the injection mold 230 and taking out the molded product 10 after the molded product 10 is manufactured will be described.

  When opening the injection mold 230 in a completely closed state as shown in FIGS. 10 and 3, the movable side mold plate 64 is moved in the direction of arrow A. In the moving unit 280, the coil spring 257 is moved until the movable side template 64 starts to move in the direction of arrow A until the fixed side insert 42 and the movable side insert 62 are separated by a distance S as shown in FIGS. Since the locking plate 252 continues to be pushed in the direction opposite to the direction of the arrow C by the urging force (the urging force), the angular pin 254 remains inserted into the angular hole 174, and the slide core 172 is movable. It remains in contact with the side nest 62. For this reason, the core nesting pin 120 is kept in the state shown in FIG. 7C (it is kept in a predetermined position).

  On the other hand, as described above, the movable unit 64 is started to move in the direction of arrow A until the fixed side insert 42 and the movable side insert 62 are separated by a distance S as shown in FIGS. In 80, since the locking block 52 is fixed to the fixed-side template 44, the outer periphery of the angular pin 54 slides on the inner periphery of the angular pin hole 74 as the movable-side insert 62 moves in the direction of arrow A. Moving in the direction of arrow A, the angular pin 54 comes out of the angular hole 74 only a little (a distance corresponding to the distance S). For this reason, the slide core 72 is relatively separated from the movable side insert 62, and thereby the core insert pin 20 is slightly removed from the forming space 34 (the formed product 10). As shown in FIG. 7 (b), the distance to be pulled out is longer than the distance at which the tip of the core insert pin 20 is extracted from the recess of the core insert pin 120.

  When opening the injection mold 230 in the completely closed state as described above, the movable side mold plate 64 starts to move in the direction of the arrow A, and the fixed side insert 42 and the movable side as shown in FIGS. Until the nest 62 is separated by the distance S, the slide core 172 of the moving unit 280 remains in contact with the movable nest 62 and does not move in the direction of arrow C, so that the core nest pin 120 remains in a predetermined position. On the other hand, as shown in FIGS. 9 and 2, the slide core 72 of the moving unit 80 moves away from the movable side nest 62 in the direction of arrow B until the fixed side nest 42 and the movable side nest 62 are separated by a distance S. Therefore, the core nesting pin 20 is removed from the predetermined position, and the tip portion is extracted from the recess of the core nesting pin 120. Thus, in the initial stage of opening the injection mold 230 in the completely closed state (until the fixed side insert 42 and the movable side insert 62 are separated by the distance S), the core insert pin 120 moves. Without moving the core nesting pin 20. Therefore, when the injection mold 230 is opened, the two core nesting pins 20 and 120 can be prevented from being damaged without interfering with each other.

  After the fixed side insert 42 and the movable side insert 62 are separated from each other by a distance S, the injection mold 230 is further opened to slide the moving unit 280 by the biasing force of the coil spring 277 as shown in FIGS. The core 172 moves in the direction of arrow C and the core nesting pin 120 comes out of the molded product 10, and in the moving unit 80, the slide core 72 moves in the direction of arrow B by the urging force of the coil spring 77, and the core nesting pin 20 is moved. Exit from the molded product 10. As a result, the molded product 10 can be taken out from the injection mold 30.

  As described above, according to the injection mold 230 of the second embodiment, when the injection mold 230 is opened and closed (when the fixed side insert 42 and the movable side insert 62 are opened and closed), the two core insert pins 20 and 120 are provided. Since two sets of moving units 80 and 280 for independently moving the two core insert pins 20 and 120 so as not to interfere with each other are incorporated in the injection mold 230, an undercut shape is formed. Therefore, even if it is a type in which the core insert pins 20 and 120 are fitted together, external power is not required, and it is possible to suppress the complexity, increase in size, and increase in price of the mold configuration.

  With reference to FIG. 11, an example in which the three core nesting pins are moved without interfering with each other will be described.

  FIG. 11 is a cross-sectional view showing how the three core insert pins 20, 120, and 220 are fitted to form a flow path shape.

  In Example 1 and Example 2, the flow path shape was made using the core nesting pins 20 and 120, but in Example 3, three core nesting pins 20, 120, and 220 were used as shown in FIG. The case where the channel shape is made will be described. The tip of the core nesting pin 20 fits into a recess formed at the tip of the core nesting pin 120, and the tip of the core nesting pin 120 fits into a recess formed at the tip of the core nesting pin 220. Include. In such a case, the core nesting pin 20 is moved by the moving unit 80 (see FIG. 1 and the like), and the core nesting pin 120 and the core nesting pin 220 are moved by the moving unit 180 (see FIG. 4 and the like, or the moving unit 280 (see FIG. 8 and the like)). See)). The moving unit that moves the core nesting pin 220 has a length of the bolt 158 longer than that of the unit that moves the core nesting pin 120, so that when closing the opened injection mold, three core nesting pins are used. Among them, the above-mentioned predetermined position is reached first, and conversely, when the closed injection mold is opened, it is moved from the predetermined position last. Thereby, even if it is a type which inserts three core insert pins in order to form an undercut shape, external power becomes unnecessary and it can control the complexity of a metal mold composition, size enlargement, and high price.

It is sectional drawing which shows the movement unit which moves the other core nest pin which has a front-end | tip part fitted in the recessed part of one core nest pin, and shows a state when an injection mold is opened. It is sectional drawing which shows a movement unit when an injection mold closes from the state of FIG. It is sectional drawing which shows a movement unit when an injection mold is completely closed from the state of FIG. It is sectional drawing which shows the movement unit which moves one core nest pin in which the recessed part in which the front-end | tip part of the other core nest pin fits was formed, and is the time of the whole injection mold being the same state as FIG. . FIG. 5 is a cross-sectional view showing the moving unit when the injection mold is closed and approaches the distance S from the state of FIG. 4, and the entire injection mold is in the same state as FIG. 2. FIG. 6 is a cross-sectional view showing the moving unit when the injection mold is completely closed from the state of FIG. 5, and is when the whole injection mold is in the same state as FIG. 3. It is the elements on larger scale which show the position of one and the other core nesting pin, (a) has shown the state from which both the one and the other core nesting pins deviated from external space, and respond | corresponds to FIG. 1 and FIG. , (B) shows a state in which only one core nesting pin reaches a predetermined position in the outer space, and the other core nesting pin does not reach a predetermined position in the outer space, corresponding to FIGS. 2 and 5. (C) shows a state in which both one and the other core nesting pins have reached a predetermined position in the outer space, and correspond to FIGS. 3 and 6. It is sectional drawing which shows the movement unit which moves one core nest pin in which the recessed part in which the front-end | tip part of the other core nest pin fits was formed, and is the time of the whole injection mold being the same state as FIG. . FIG. 9 is a cross-sectional view showing the moving unit when the injection mold is closed and approaches the distance S from the state of FIG. 8, and the entire injection mold is in the same state as FIG. 2. FIG. 10 is a cross-sectional view showing the moving unit when the injection mold is completely closed from the state of FIG. 9, and the entire injection mold is in the same state as FIG. 3. It is sectional drawing which shows a mode that three core insert pins fit together and make a flow-path shape. (A) is a perspective view which shows an example of the molded article which has an undercut shape, (b) is a perspective view which shows the molded article shown to (a), and the member (core nesting pin) inserted in its internal space. It is. It is sectional drawing which shows the example made into the structure which abuts two core nest pins on the surface. It is sectional drawing which shows a mode that two core insert pins fit together and it makes a flow-path shape.

Explanation of symbols

30 Injection mold 10 Molded product 34 External space 40 Fixed mold 42 Fixed side insert 60 Movable mold 62 Moving side insert 80, 180 Moving unit 20, 120, 220 Core nesting pin 50 Fixed side moving unit 70 Moving side moving unit 72 Slide Core 77, 157, 177, 257 Coil spring

Claims (7)

A fixed-side nesting and a movable-side nesting that form an outer space that forms an outer shape of the molded product by being closed and in contact with each other; and at least two core nesting pins that are inserted into and withdrawn from the outer space from directions intersecting each other, One core nesting pin of the at least two core nesting pins is formed with a recess into which the tip of the other core nesting pin is fitted, and the one of the core nesting pins is formed in the outer space. In an injection mold in which a molded product is injection-molded with the tip of the other one core nesting pin fitted in the recess of the core nesting pin of
The one core nesting pin and the other one core nesting so that the one core nesting pin and the other one core nesting pin do not interfere with each other when the fixed side nesting and the movable side nesting are opened and closed. An injection mold characterized by comprising a moving unit built in the pin for moving the pin. The mobile unit is
When the fixed side insert and the movable side insert are opened from the closed state, the other one core insert pin is moved in a direction to be taken out from the outer space, and the tip portion is moved to the one piece. After the core nesting pin is extracted from the recess, the two core nesting pins are moved so as to move the one core nesting pin in a direction to be taken out from the outer space, while the fixed side nesting and the movable nesting pin are moved. When the side nesting is closed from the opened state, after inserting the one core nesting pin into the outer space, the tip of the other one core nesting pin is moved to the one core nesting pin. The injection mold according to claim 1, wherein the two core nesting pins are moved so as to be fitted into the recesses. The mobile unit is
When the fixed side insert and the movable side insert are opened from the closed state, the one end of the other core insert pin is withdrawn from the concave portion of the one core insert pin. When the fixed core insert and the movable insert are closed from the opened state, the other core insert pin is stopped until the one core insert pin enters the outer space. The injection mold according to claim 1 or 2, wherein the tip portion of the single core nesting pin is not fitted into the concave portion of the single core nesting pin. The mobile unit is
When the fixed side insert and the movable side insert are opened from the closed state, the one end of the other core insert pin is extracted from the recess of the one core insert pin. The urging member for urging the single core nesting pin so as to keep the core nesting pin located in the outer space is provided. Injection mold. A slide core that moves in the longitudinal direction of the one core nesting pin, the one core nesting pin being fixed;
5. The injection mold according to claim 4, wherein the biasing member biases the slide core in the closing direction. A slide core that moves in the longitudinal direction of the one core nesting pin, the one core nesting pin being fixed;
5. The injection mold according to claim 4, wherein the urging member urges the slide core toward the tip of the one core insert pin. 7. The injection mold according to claim 4, 5, or 6, wherein the biasing member is a coil spring.

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