JP2008119917A - Injection-molding mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the flexibility of arranging a gate and cooling piping in an injection-molding mold and to obtain a product improved in dimensional accuracy by minimizing the number of parts constituting the mold. <P>SOLUTION: In the injection-molding mold, a fixed mold slide block 11 and a movable mold slide block 16, by the engagement of inclined pins 15 and 17 with through-holes 15a and 17a, slide in the arrow direction simultaneously with mold clamping, are engaged while moving until their tips reach positions indicated by an imaginary line, and made to closely contact in a mold clamping state, and form the cavity PC of an organic synthetic resin product having an uneven part which forms undercuts in the mold rejection direction on the inner surfaces of the through-holes. When injection molding and cooling are finished and the mold is opened, the slide blocks 11 and 16, since they slide in the direction opposite to the arrow direction, are separated from the inner surfaces of the through-holes of the cavity PC of the organic synthetic resin product, and retreat to positions where they are prevented from interfering the undercuts of the product, thus the mold can be opened smoothly. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  In the present invention, an organic synthetic resin product having an uneven portion that forms an undercut in a die-cutting direction on an inner surface of a through-hole including a ring member into which an O-ring / seal ring is fitted to an inner surface has a simple structure by injection molding. Moreover, the present invention relates to an injection mold for obtaining with high accuracy.

  Conventionally, in Patent Document 1, a male mold for forming an inner surface of a through hole is used as a mold for obtaining an organic synthetic resin product having an uneven portion that forms an undercut in the die-cutting direction on the inner surface of the through hole. The portion is divided into a conical core core, a first wedge core and a second wedge core that slide in the inclination direction of the inclined surface of the core core, and the first wedge core is centered following the retreat of the core core. It is proposed that the second wedge-shaped cores are gathered and released in the space generated by the release of the first wedge-shaped cores after being collected, reduced and released.

  However, in the injection mold disclosed in Patent Document 1, the first wedge-shaped core and the second wedge-shaped core are all arranged in one mold, and the wedge-shaped core is retracted when the conical core is retracted. Since it must be configured to slide in the inclined direction of the inclined surface of the core core while preventing the backward movement, the structure of one mold becomes extremely complicated, resulting in looseness between the parts. There was a problem that the dimensional accuracy of the obtained product was lowered.

Therefore, in the patent invention described in Patent Document 2, the male part forming the through hole is composed of a center core and a main slide core and a sub slide core that are alternately arranged along the outer periphery thereof. The core has a concave / convex outer surface corresponding to the concave / convex portion of the through-hole, the center core and main slide core are provided in one mold, and the secondary slide core is provided in the other mold. The main slide core slides on the center side of the resulting space and can be released from the mold, and the secondary slide core slides on the center side of the resulting space to enable extraction of organic synthetic resin products. An injection molding die is disclosed. Thus, an undercut resin product having a concavo-convex portion in the through hole can be precisely and efficiently molded.
JP 59-38032 A Japanese Patent No. 3537744

  However, in the injection mold described in Patent Document 2, the slide mechanism of the main slide core and the sub slide core is provided on the outer periphery of the mold on the outside of the product cavity, which is caused by the high temperature during the injection molding. It is easily affected by thermal expansion and it is difficult to ensure a smooth sliding operation. In addition, since the slide mechanism of both slide cores is an L-shape having a thin waist folded portion, the strength cannot be ensured, and a smooth slide operation is difficult. Furthermore, since both the slide cores are divided into four parts, there is a problem that the number of parts constituting the mold is increased and play is likely to occur, and a product with higher dimensional accuracy cannot be obtained.

  In view of this, the present invention provides a slide member that slides in a plane, which is divided into a fixed mold and a movable mold, so that the slide mechanism can be accommodated inside the product cavity, and the arrangement of gates and cooling pipes can be freely set. An object of the present invention is to provide an injection mold capable of obtaining a product with higher dimensional accuracy by increasing the degree and minimizing the number of parts constituting the mold.

  An injection mold according to the invention of claim 1 is an injection comprising a fixed mold and a movable mold for injection molding of an organic synthetic resin product having an uneven portion that forms an undercut in the mold release direction on the inner surface of the through hole. A molding die having a width equal to or larger than the size of the undercut in a direction perpendicular to the moving direction of the movable die from the center portion to the outer portion of the fixed die disposed at the center portion of the fixed die. A pair of fixed-type slide blocks provided so as to be slidable, and a center portion of the movable mold, and extending in the direction perpendicular to the moving direction of the movable mold from the center to the outer side of the movable mold. The front of the organic synthetic resin product is slidably provided with a width equal to or larger than the size of the undercut, and is slid and fitted to the pair of fixed-type slide blocks that have been slid to the outer end. A pair of movable slide blocks that form a cavity portion that abuts the inner surface of the through-hole, and a fixed substrate that is fixed between the pair of fixed slide blocks and the pair of fixed slide blocks. The sliding surface is fixed to the fixed-type substrate between the first locking block formed with a taper corresponding to the width of sliding of the pair of fixed-type slide blocks and the pair of movable-type slide blocks. And a sliding surface with the pair of movable slide blocks includes a second locking block having a taper formed by a width that the pair of movable slide blocks slide. The fixed slide block, the pair of movable slide blocks, the first locking block, and the second locking block are all The one in which an organic synthetic resin product is placed inside the cavity to be injection molded.

  According to a second aspect of the present invention, there is provided an injection mold according to the first aspect, wherein the first locking block and the second locking block are integrated into one locking block.

  According to a third aspect of the present invention, there is provided an injection mold according to the first or second aspect, wherein the pair of fixed mold slide blocks and the pair of movable mold slide blocks include the fixed mold substrate. Alternatively, inclined pins attached to the movable substrate and fixed at an angle different from the taper of the first locking block and the second locking block or the one locking block are slidably fitted. The pair of fixed-type slide blocks and the pair of movable-type slide blocks slide along the angle of the inclined pin during mold clamping, and the outer periphery of the fixed type and the movable type. The cavity portion on the inner surface side of the through hole of the organic synthetic resin product is configured by sliding to the side, and when the mold is opened, the fixed mold substrate and the movable mold base are formed. That slides to the center side of the fixed mold and the movable mold so as to separate from the inner surface of the through hole of the organic synthetic resin product that is injection-molded by sliding along the angle of the inclined pin as the gap is separated It is.

  An injection mold according to the invention of claim 1 is an injection comprising a fixed mold and a movable mold for injection molding of an organic synthetic resin product having an uneven portion that forms an undercut in the mold release direction on the inner surface of the through hole. Molding mold that can slide over the width of the undercut in the direction perpendicular to the moving direction of the movable mold from the center to the outside of the fixed mold located at the center of the fixed mold A pair of fixed slide blocks provided, and a width that is arranged in the central part of the movable mold and that is larger than the size of the undercut in the direction perpendicular to the moving direction of the movable mold from the central part to the outer part of the movable mold Slidably fitted to a pair of fixed slide blocks slid to the outer end and slid to the outer end to form a cavity portion that abuts the inner surface of the through hole of the organic synthetic resin product. A pair of movable slide blocks and a pair of fixed slide blocks are fixed to a fixed substrate, and a pair of fixed slide blocks slide on the sliding surfaces of the pair of fixed slide blocks. The first locking block having a taper corresponding to the width and the pair of movable slide blocks are fixed to a fixed substrate and the sliding surfaces of the pair of movable slide blocks are a pair. A second locking block having a taper formed by the width of sliding of the movable slide block, a pair of fixed slide blocks, a pair of movable slide blocks, a first locking block, and The second locking block is all disposed inside the cavity in which the organic synthetic resin product is injection-molded.

  Here, as a mechanism for sliding a pair of fixed slide blocks and a pair of movable slide blocks, each pair of slide blocks is urged by springs toward the center of the fixed and movable molds. When the mold is clamped, it slides outwardly against the urging force of the spring by sliding along the taper of the first locking block and the second locking block, and when the mold is opened, the cavity is formed. It is possible to adopt a method in which the mold is slid to the center side by an urging force and released.

  In addition, without using a spring, an inclined pin inclined at an angle different from the taper is slidably fitted to a pair of fixed type slide blocks and a pair of movable type slide blocks. A pair of fixed-type slide blocks and a pair of movable-type slide blocks slide outward along the inclined pins to form cavities, and when opening the mold, slide toward the center along the inclined pins and organic synthetic resin products It is also possible to adopt a method of releasing from the inner surface of the through hole.

  As described above, in the injection mold according to the present invention, the fixed slide block and the movable slide block that form the cavity portion that contacts the inner surface of the through hole are divided into the minimum required two parts, A product with higher dimensional accuracy can be obtained by minimizing the number of parts making up the mold to prevent backlash. Also, by placing all the parts that make up the slide mechanism inside the product cavity, the degree of freedom in the arrangement of the gates and cooling pipes is greatly improved. Furthermore, the slide member is a block that slides in a direction perpendicular to the moving direction of the movable type, thereby realizing a significant improvement in the strength of the slide member.

  In particular, when the organic synthetic resin product having an uneven portion that forms an undercut in the die-cutting direction on the inner surface of the through hole is a sealing component including a ring member that fits an O-ring / seal ring or the like into the inner surface By dividing the slide block into the minimum required two parts, the division and alignment part is minimized, and the adverse effect on the sealing performance due to the occurrence of minute steps in the product due to the accuracy deviation of the division and alignment part is also minimized. The effect that it can suppress to is obtained.

  In this way, by providing a slide member that slides in two, which is divided into a fixed mold and a movable mold, the slide mechanism fits inside the product cavity, and the degree of freedom in the arrangement of gates and cooling pipes As the number of parts increases, by minimizing the number of parts constituting the mold, an injection mold capable of obtaining a product with higher dimensional accuracy can be obtained.

  The injection mold according to the invention of claim 2 is one in which the first locking block and the second locking block are integrated into one locking block. Thereby, in addition to the effect of claim 1, since the number of parts constituting the injection mold is reduced, the mold structure is simplified and the accuracy of the obtained product is further improved. Can do.

  In this way, by providing a slide member that slides in two, which is divided into a fixed mold and a movable mold, the slide mechanism fits inside the product cavity, and the degree of freedom in the arrangement of gates and cooling pipes As the number of parts increases, by minimizing the number of parts constituting the mold, an injection mold capable of obtaining a product with higher dimensional accuracy can be obtained.

  The injection mold according to the invention of claim 3 is attached to the fixed substrate or the movable substrate on the pair of fixed slide blocks and the pair of movable slide blocks, respectively. An inclined pin fixed at an angle different from the taper of the block and the second locking block or one locking block is slidably fitted, and a pair of fixed slide blocks and a pair of movable slides The block constitutes a cavity portion on the inner surface side of the through hole of the organic synthetic resin product by sliding along the angle of the inclined pin during mold clamping and sliding to the outer peripheral side of the fixed mold and the movable mold, When the mold is opened, the injection molding of the organic synthetic resin product is performed by sliding along the angle of the inclined pin as the fixed substrate and the movable substrate are separated from each other. Slides on the center side of the fixed mold and the movable mold away from the hole inner surface.

  As described above, the injection mold according to the present invention includes an inclined pin slidably fitted to both slide blocks as a mechanism for sliding a pair of fixed slide blocks and a pair of movable slide blocks. Therefore, when the fixed mold and the movable mold are closed without using a spring, the pair of fixed slide blocks and the pair of movable slide blocks are automatically slid to the outer peripheral side and the inner surface of the cavity. When a fixed mold and a movable mold are opened, a pair of fixed slide blocks and a pair of movable slide blocks automatically slide to the center side when the fixed mold and the movable mold are opened. Release from the inner surface.

  Therefore, since a spring is not used, there is no need for replacement due to wear of parts, and a highly durable injection mold that can be used continuously over a long period of time is obtained. Further, the structure of the mold becomes simpler and the strength is further improved.

  In this way, by providing a slide member that slides in a plane divided into a fixed mold and a movable mold, respectively, and by providing an inclined pin that automatically slides the slide member as the mold opens and closes, By making the mold more durable, the sliding mechanism fits inside the product cavity, increasing the degree of freedom of gate arrangement and cooling pipe arrangement, and by minimizing the number of parts that make up the mold It becomes an injection mold capable of obtaining a product with high dimensional accuracy.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 7.

  FIG. 1 is a front view showing an overall configuration in a state where an injection mold according to an embodiment of the present invention is opened. FIG. 2 is a perspective view showing the inner surface configuration of the fixed mold and the movable mold in a state where the mold of the injection mold according to the embodiment of the present invention is opened. 3A is a plan view showing the structure of the main part of the fixed mold of the injection mold according to the embodiment of the present invention, FIG. 3B is a plan view showing the structure of the main part of the movable mold, and FIG. ) Is a plan view showing the state in which the slide block moves and the cavity of the organic synthetic resin product is formed when the mold is clamped, as seen through the mold, and (d) is the injection molding according to the embodiment of the present invention. It is a partial cross section perspective view which shows the organic synthetic resin product obtained by the metal mold | die.

  FIG. 4 is an exploded perspective view showing each part constituting the fixed mold of the injection mold according to the embodiment of the present invention. FIG. 5 is an exploded perspective view showing parts constituting the movable mold of the injection mold according to the embodiment of the present invention. 6A is a plan view showing a fixed mold of an injection mold according to an embodiment of the present invention, FIG. 6B is a cross-sectional view taken along the line AA in FIG. 6A, and FIG. It is -B sectional drawing. FIG. 7A is a plan view showing the movable mold of the injection mold according to the embodiment of the present invention, FIG. 7B is a sectional view taken along the line C-C in FIG. 7A, and FIG. It is -D sectional drawing.

  First, the entire structure of an injection mold according to an embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, an injection mold 1 according to this embodiment is used for a horizontal injection molding machine, and is divided into a fixed mold 2 and a movable mold 3. The fixed mold 2 and the movable mold 3 are connected by a pair of external tension bars 4. The fixed mold 2 includes four plates (made of SKD steel plate) of a first plate (fixed side mounting plate) 2A, a second plate 2B, a third plate 2C, and a fourth plate 2D. Four guide pins 10 pass through the plates 2A, 2B, 2C, and 2D from the first plate 2A side.

  On the other hand, from the side of the fourth plate 2D, four internal tension bars 9 pass through the fourth plate 2D and the third plate 2C and are screwed and fixed to the second plate 2B. A coil spring 8A is attached between the fourth plate 2D and the third plate 2C, and a coil spring 8B is attached between the third plate 2C and the second plate 2B. Here, the spring force of the coil spring 8A is set larger than the spring force of the coil spring 8B.

  Further, the fourth plate 2D is provided with a hole through which the bolt head can slide, and four bolts 14A are screwed and fixed to the third plate 2C. Similarly, the bolt head can slide on the first plate 2A. A hole is provided, and four bolts 14B are screwed and fixed to the second plate 2B. Thus, the opening amount of the fourth plate 2D and the third plate 2C and the opening amount of the first plate 2A and the second plate 2B at the time of mold opening are determined. Then, on the screw cylinder side of an injection molding machine (not shown) of the first plate (fixed side mounting plate) 2A, the tip of an injection molding nozzle (not shown) of the screw cylinder is accurately positioned on the sprue bush of the first plate 2A. The locating ring 5 is fixed.

  When the fixed mold 2 having such a structure is opened, since the spring force of the coil spring 8A is larger than the spring force of the coil spring 8B as described above, first, the fourth plate 2D and the third plate 3D are caused by the elastic force of the coil spring 8A. The space between the plate 2C and the third plate 2C and the second plate 2B are opened by the elastic force of the coil spring 8B. In this state, when the movable mold 3 further moves away from the fixed mold 2, the fourth plate 2 </ b> D is pulled by the external pull rod 4, so that the second plate 2 </ b> B into which the internal pull rod 9 is screwed is pulled and the second plate 2 </ b> B is pulled. The plate 2B is separated from the first plate (fixed side mounting plate) 2A. In this way, the organic synthetic resin filled in the sprue PS and the runner PL by injection molding is removed from the fixed mold 2 and removed by the robot.

  On the other hand, the movable mold 3 includes a cavity plate 3A, a movable side mounting plate 3B, and a pair of spacer blocks 7. Between the pair of spacer blocks 7, two ejector plates 6 are slidably provided. Two ejector pins 6a and 6b for projecting a product obtained by injection molding are fixed to the left ejector plate 6 of the two. In the cavity plate 3A, a product-shaped space (cavity) PC is formed in a state where the fixed mold 2 and the movable mold 3 are clamped.

  In the clamped state, the four plates 2A, 2B, 2C, and 2D are also in close contact with the sprue PS and runner PL provided in the four plates 2A, 2B, 2C, and 2D of the fixed mold 2. A high temperature molten organic synthetic resin injected at a high pressure from an injection molding nozzle (not shown) flows into the cavity PC from the gate G through the sprue PS and runner PL. The product obtained by cooling and solidifying is ejected by the ejector pins 6a and 6b in a state where the fixed mold 2 and the movable mold 3 are opened as shown in FIG.

  Next, referring to FIG. 2 showing the inner surface of the fixed mold 2 and the movable mold 3 by removing the external pulling bar 4 from the injection mold 1 according to the present embodiment in a state of being removed from the injection molding machine. Further explanation will be given. As shown in FIG. 2, the fixed mold 2 shows a state in which the four plates 2A, 2B, 2C, and 2D are in close contact and are clamped. The bolt heads of the four internal tension bars 9 provided on the fixed mold 2 and the protruding portions of the four guide pins 10 are provided with four holes 3Aa provided on the cavity plate 3A of the movable mold 3 and the cavity plate 3A. And 4 holes 7a provided through the spacer block 7. As a result, the fourth plate 2D of the fixed mold 2 and the cavity plate 3A of the movable mold 3 are in close contact with each other during mold clamping.

  A pair of movable slide blocks 16 slidable in the direction of the arrow are provided at the center of the cavity plate 3A of the movable mold 3, and each of the pair of movable slide blocks 16 has inclined through holes 15a. It has been drilled. On the other hand, a pair of inclined pins 15 are fixed to the center of the fixed mold 2 at positions corresponding to these through holes 15a. The inclination angles of these inclination pins 15 are the same as the taper angle of the outer surface of the second locking block 13, and a pair of inclination pins 15 are inserted into the through holes 15 a of the pair of movable slide blocks 16 during mold clamping. By fitting and guiding the pair of movable slide blocks 16, the pair of movable slide blocks 16 slide in the direction of the arrow to form part of the cavity PC.

  On the other hand, a pair of fixed slide blocks 11 provided in the center of the fixed mold 2 and slidable in the direction of the arrow are also provided with inclined through holes 17a, respectively, which are provided at the back of the fixed mold 2. A pair of inclined pins 17 (not shown) are fitted into the through-holes 17a to guide the pair of fixed slide blocks 11, so that the pair of fixed slide blocks 11 slide in the direction of the arrow and the cavity PC Form part. In FIG. 2, since the fixed mold 2 is clamped, the pair of fixed mold slide blocks 11 are slid to the outer end in the arrow direction.

  As described above, when the fixed mold 2 and the movable mold 3 are clamped, the pair of fixed slide blocks 11 enter between the pair of movable slide blocks 16 and the pair of fixed mold slide blocks. 11 and a pair of movable slide blocks 16 are guided by a pair of inclined pins 17 and a pair of inclined pins 15, respectively, and slide in the direction of the arrow, thereby forming an undercut in the die release direction on the inner surface of the through hole. The inner surface of the through hole of the cavity PC of the seal ring which is an organic synthetic resin product having an uneven portion is formed.

  This point will be further described with reference to FIG. As shown in FIG. 3A, in the open state of the fixed mold 2, the pair of fixed slide blocks 11 are located at the center side end, and the inclined pins 17 are fitted in the through holes 17a. Therefore, it slides in the direction of the arrow together with mold clamping and moves until the tip comes to the position indicated by the imaginary line (to the outer end). On the other hand, as shown in FIG. 3B, when the movable mold 3 is in the open state, the pair of movable slide blocks 16 are positioned at the center end, and the inclined pins 15 are fitted into the through holes 15a. By doing so, it slides in the direction of the arrow together with mold clamping and moves until the tip comes to the position indicated by the imaginary line (to the outer end).

  At this time, a level difference is provided on both side surfaces of the pair of fixed slide blocks 11, and a level difference is provided on the inner side of the pair of movable type slide blocks 16. The pair of fixed-type slide blocks 11 and the pair of movable-type slide blocks 16 are fitted while sliding in the direction of the arrow, and in the mold-clamped state, as shown in FIG. Cavity PC of the organic synthetic resin product which has the uneven | corrugated | grooved part which forms an undercut in the mold release direction in the hole inner surface is formed.

  When the mold is opened after the injection molding / cooling is completed, the pair of fixed mold slide blocks 11 and the pair of movable mold slide blocks 16 slide in the direction opposite to the arrow. Since the slide length of both slide blocks 11 and 16 is larger than the width of the undercut, the pair of fixed slide blocks 11 and the pair of movable slide blocks 16 are separated from the inner surface of the through hole of the cavity PC. Since the product is retracted to a position where it does not hit the undercut of the product, the mold can be opened smoothly.

  A ring member for fitting the O-ring / seal ring as the organic synthetic resin product according to the present embodiment thus obtained into the inner surface will be described with reference to FIG. As shown in FIG. 3 (d), the organic synthetic resin product P having an uneven portion that forms an undercut in the die-cutting direction on the inner surface of the through hole according to the present embodiment is fitted with an O-ring / seal ring on the inner surface. It is a ring member, and as shown in a partial cross section, there is a recess into which the O-ring / seal ring is fitted over the entire center portion of the inner surface of the through hole, and this portion is an undercut UC of the ring member P. .

  Next, each part which comprises the fixed mold | type 2, and its connection relation are demonstrated with reference to FIG. As shown in FIG. 4, the second locking block 12 is fixed to the third plate 2 </ b> C, and tapers 12 a are provided on both side surfaces of the second locking block 12. A pair of inclined pins 17 having an inclination angle different from the angle of the taper 12 a are fixed to both sides of the second locking block 12. A circular block 20 is disposed between the third plate 2C and the fourth plate 2D.

  The circular block 20 includes a pair of guide blocks 22 and a pair of first locking blocks 13, and the pair of guide blocks 22 includes a taper 13 a provided on the first locking block 13. A pair of inclined pins 15 having an inclination angle different from the angle is fixed. In addition, a guide groove 22a is provided at the inner lower portion of the pair of guide blocks 22, and the protrusion 11b of the fixed mold slide block 11 is fitted into the guide groove 22a without being detached from the fixed mold 2. The movable mold 3 is slidably mounted in a direction perpendicular to the moving direction of the movable mold 3.

  Further, a rectangular through hole 23 is formed between the pair of circular through holes 21 and the pair of first locking blocks 13 in the circular block 20. The pair of circular through holes 21 are sized to allow the pair of inclined pins 17 to pass through in an inclined state, and the rectangular through holes 23 are sized to allow the second locking block 12 to pass through. . A large through hole 2Da into which the circular block 20 is fitted is formed in the center of the fourth plate 2D, and the pair of inclined pins 17 and the second locking block 12 are fitted into the circular block 20 so as to pass therethrough. By fitting the circular block 20 into the hole 2Da, the third plate 2C and the fourth plate 2D can be in close contact with each other during mold clamping.

  Next, each part which comprises the movable mold | type 3, and its connection relation are demonstrated with reference to FIG. As shown in FIG. 5, a circular block 25 is disposed between the cavity plate 3 </ b> A and the ejector plate 6. The circular block 25 is provided with a pair of guide blocks 26 and a pair of stoppers 27, and a pair of through holes 25b through which the ejector pins 6a and 6b penetrate. Further, a guide groove 26a is provided at the inner lower part of the pair of guide blocks 26, and the protrusion 16a of the movable slide block 16 is fitted into the guide groove 26a without being detached from the movable mold 3. The movable mold 3 is slidably mounted in a direction perpendicular to the moving direction of the movable mold 3.

  On the back side of the cavity plate 3A, there is provided a recess 3Ac that forms a part of a through hole into which the circular block 25 is fitted. On the front side of the cavity plate 3A, the movable slide block 16 is fitted and the cavity plate 3A is fitted. A recess 3Ab that forms part of a through hole that forms the outer peripheral side is provided, and a pair of penetrations through which the ejector pins 6a and 6b penetrate the ring-shaped wall surface formed between the recess 3Ab and the recess 3Ac. A hole 3Ad is formed.

  Next, the cross-sectional structure of the fixed mold 2 will be described with reference to FIG. As shown in FIG. 6A, when the fixed mold 2 is removed and placed on a flat surface, the uppermost portion has the fourth plate 2D, and the lowermost portion shows a part of the first plate 2A. FIG. 6B shows the AA cross section of the fixed mold 2 with the first plate 2A facing upward, and the BB cross section is viewed with the first plate 2A facing upward. FIG. 6C is a sectional view shown in FIG.

  As shown in FIGS. 6B and 6C, a sprue PS is drilled in the center of the first plate 2A and the second plate 2B, and the runner PL is followed by the third plate 2C and the fourth plate. Carved in plate 2D. The tip of the runner PL is opened as a gate G on the surface of the fourth plate 2D. A pair of inclined pins 15 shown in FIG. 6B are fitted into through holes 15a drilled in a pair of movable slide blocks 16 provided in the movable mold 3, and FIG. The pair of inclined pins 17 shown in c) are fitted into the through holes 17a formed in the pair of fixed slide blocks 11 as shown in the figure.

  Next, the cross-sectional structure of the movable mold 3 will be described with reference to FIG. As shown in FIG. 7A, when the movable mold 3 is removed and placed on a flat surface, the uppermost part has the cavity plate 3A, and the lowermost part shows a part of the movable attachment plate 3B. FIG. 7B is a cross-sectional view of the movable die 3 taken along the cavity plate 3A with the cavity plate 3A facing up, and a DD cross-section seen with the cavity plate 3A up. It is sectional drawing shown by FIG.7 (c).

  As shown in FIGS. 7B and 7C, a pair of movable slide blocks 16 are fitted into the recesses 3Ab formed in the cavity plate 3A. The pair of inclined pins 15 of the fixed mold 2 described above are fitted into the drilled through holes 15a. Then, as the pair of inclined pins 15 enters the back of the through-hole 15a during mold clamping, the pair of movable mold slide blocks 16 slide so as to approach the inner surface of the recess 3Ab, and the mold clamping is performed. When completed, a space (cavity) PC in the shape of the product P is formed between the pair of movable slide blocks 16 and the inner surface of the recess 3Ab.

  Similarly, as the pair of fixed mold slide blocks 11 described above, the pair of fixed mold slide blocks 11 are arranged on the inner surface of the recess 3Ab as the pair of inclined pins 17 enter the back of the through hole 17a during mold clamping. When the mold clamping is finished, a space (cavity) PC in the shape of the product P is formed between the pair of fixed mold slide blocks 11 and the inner surface of the recess 3Ab.

  When mold opening is performed after injection molding is performed, the pair of movable slide blocks 16 and the pair of inclined pins 15 and 17 are pulled out from the through holes 15a and 17a. The pair of fixed-type slide blocks 11 slide toward the center, leave the inner surface of the injection molded product P, and return to the original position. Since the slide length of the pair of movable slide blocks 16 and the pair of fixed slide blocks 11 at this time is larger than the width of the undercut UC of the injection molded product P, the movable slide blocks 16 and the pair of pairs are movable. There is no fear that the fixed mold slide block 11 is caught by the injection molded product P, and the mold can be opened reliably.

  As described above, the injection mold 1 according to the present embodiment is provided with the sliding members 11 and 16 that are divided into two planes, the fixed mold 2 and the movable mold 3, respectively. By providing the inclined pins 15 and 17 that automatically slide the slide members 11 and 16 in accordance with the opening and closing, the mold becomes more durable, the slide mechanism is accommodated inside the product cavity PC, and the gate G is disposed. Further, the degree of freedom of arrangement of the cooling pipes is increased, and the product P with higher dimensional accuracy can be obtained by minimizing the number of parts constituting the mold.

  In the present embodiment, the case of a horizontal mold used in a horizontal injection molding machine as an injection mold has been described, but a vertical injection mold used in a vertical injection molding machine can also be used. . In this case, the fixed mold is the upper mold and the movable mold is the lower mold.

  Further, in the present embodiment, the case where the first locking block 12 and the second locking block 13 are separately provided as the locking blocks has been described, but the first locking block and the second locking block are It can also be integrated into one locking block. As a result, it is possible to obtain an effect that the structure of the injection mold becomes simpler.

  In practicing the present invention, the configuration, shape, material, size, quantity, connection relationship, and the like of other portions of the injection mold are not limited to the present embodiment.

FIG. 1 is a front view showing an overall configuration in a state where an injection mold according to an embodiment of the present invention is opened. FIG. 2 is a perspective view showing the inner surface configuration of the fixed mold and the movable mold in a state where the mold of the injection mold according to the embodiment of the present invention is opened. 3A is a plan view showing the structure of the main part of the fixed mold of the injection mold according to the embodiment of the present invention, FIG. 3B is a plan view showing the structure of the main part of the movable mold, and FIG. ) Is a plan view showing the state in which the slide block moves and the cavity of the organic synthetic resin product is formed when the mold is clamped, as seen through the mold, and (d) is the injection molding according to the embodiment of the present invention. It is a partial cross section perspective view which shows the organic synthetic resin product obtained by the metal mold | die. FIG. 4 is an exploded perspective view showing each part constituting the fixed mold of the injection mold according to the embodiment of the present invention. FIG. 5 is an exploded perspective view showing parts constituting the movable mold of the injection mold according to the embodiment of the present invention. 6A is a plan view showing a fixed mold of an injection mold according to an embodiment of the present invention, FIG. 6B is a cross-sectional view taken along the line AA in FIG. 6A, and FIG. It is -B sectional drawing. FIG. 7A is a plan view showing the movable mold of the injection mold according to the embodiment of the present invention, FIG. 7B is a sectional view taken along the line C-C in FIG. 7A, and FIG. It is -D sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Injection mold 2 Fixed type 3 Movable type 4 External tension bar 6 Ejector plate 6a, 6b Ejector pin 9 Internal tension bar 10 Guide pin 11 Fixed type | mold slide block 12 1st locking block 13 2nd locking block 15, 17 Inclined Pin 16 Movable Slide Block G Gate P Organic Synthetic Resin Product PC Cavity PL Runner PS Sprue UC Undercut

Claims (3)

An injection mold comprising a fixed mold and a movable mold for injection molding of an organic synthetic resin product having an uneven portion that forms an undercut in the mold release direction on the inner surface of the through hole,
1 slidably provided with a width equal to or larger than the size of the undercut in a direction perpendicular to the moving direction of the movable mold from the center to the outer side of the fixed mold disposed in the center of the fixed mold. A pair of fixed slide blocks;
The movable mold is disposed at the center of the movable mold, and is provided to be slidable at a width equal to or larger than the size of the undercut in a direction perpendicular to the moving direction of the movable mold from the central portion to the outer portion of the movable mold. A pair of movable slide blocks that form a cavity portion that contacts the inner surface of the through hole of the organic synthetic resin product by sliding and fitting to the pair of fixed slide blocks that slide to the end and the outer end When,
The fixed surface is fixed to the fixed substrate between the pair of fixed slide blocks, and the sliding surface with the pair of fixed slide blocks is tapered by the width of the slide of the pair of fixed slide blocks. A first locking block formed with:
The pair of movable slide blocks are fixed between the pair of movable slide blocks, and the sliding surface with the pair of movable slide blocks is tapered by the width that the pair of movable slide blocks slide. A second locking block formed with
The pair of fixed slide blocks, the pair of movable slide blocks, the first locking block, and the second locking block are all disposed inside a cavity in which the organic synthetic resin product is injection molded. A mold for injection molding, characterized in that   The injection mold according to claim 1, wherein the first locking block and the second locking block are integrated into one locking block. The pair of fixed type slide blocks and the pair of movable type slide blocks are attached to the fixed type substrate or the movable type substrate, respectively, and the first locking block and the second locking block or An inclined pin fixed at an angle different from the taper of the one locking block is slidably fitted,
The pair of fixed-type slide blocks and the pair of movable-type slide blocks slide along the angle of the inclined pin and slide toward the outer peripheral side of the fixed type and the movable type at the time of clamping. As a result, a cavity portion on the inner surface side of the through hole of the organic synthetic resin product is formed, and the mold is slid along the angle of the inclined pin as the fixed substrate and the movable substrate are separated when the mold is opened. 3. The injection molding according to claim 1, wherein the injection molding is slid toward the center side of the fixed mold and the movable mold so as to be separated from the inner surface of the through hole of the organic synthetic resin product that is injection molded by moving. Mold.

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