JP2006150864A - Injection mold assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance production efficiency while preventing the occurrence of the molding failure of an injection-molded product formed into a thin plate shape. <P>SOLUTION: A pair of molds 12 and 13 are respectively equipped with mold main bodies 12b and 13b having molding surfaces 12a and 13a and ring members 20 and 30 are separately fitted to the outer peripheral parts of the mold main bodies 12b and 13b. A pair of the ring members 20 and 30 are brought into contact with each other at the time of mold clamping to demarcate a cavity 11 by the inner peripheral surfaces of at least either one of the molding surfaces 12a and 13a and the ring members 20 and 30. At least either one of the ring members 20 and 30 is constituted so that first recessed parts 23 and 34 becoming the non-contact state with the other one of the ring members are formed to the contact surfaces 20a and 30a with the other ring member in a mold clamping state. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an injection mold apparatus suitable for molding a thin plate-like injection molded product.

2. Description of the Related Art Conventionally, for example, optical discs such as a DVD (Digital Versatile Disk) are formed by injection molding.
As an injection mold apparatus for manufacturing this type of injection molded product, for example, as shown in Patent Document 1 below, it is provided so as to be able to approach and separate, and a cavity is formed between mold surfaces in a clamped state. A pair of molds is provided, and one of the molds is formed by injecting a molten resin into the cavity and solidifying the molten resin in the cavity in a state of contact, thereby A stamper portion configured to form an uneven portion for recording information on the surface, and each of the pair of molds includes a mold body having the mold surface, and outer peripheries of these mold bodies Ring members are fitted to the respective parts, and at the time of mold clamping, the pair of ring members abut each other, so that at least the mold surface and the inner peripheral surface of the ring member in the other mold The configuration in which the cavity is defined is disclosed.

  In the method of manufacturing an injection molded product using such an injection mold apparatus, the molten resin is injected into the cavity and immediately solidified for the purpose of improving the manufacturing efficiency of the injection molded product. In order to make this happen, the temperature of the mold body is set low. Specifically, by setting the mold temperature of the other mold not provided with the injection part and the stamper part to be lower than that of the one mold provided with the injection part and the like, the injection The injected molten resin is solidified at an early stage while maintaining the viscosity of the molten resin injected into the cavity through the portion at a predetermined value or higher. By maintaining the viscosity of the molten resin at a predetermined value or higher, the molten resin can be surely spread over the entire area in the cavity including the transfer uneven portion formed on the surface of the stamper portion facing the cavity. Thus, the occurrence of molding defects including the formation of the concave and convex portions for information recording is prevented.

As a means for realizing such a configuration, for example, the temperature of the temperature-controlled water in the temperature-controlled water channel provided in the other mold is set lower than that provided in the one mold. (Hereinafter referred to as “first means”), a cooling water channel is formed in the ring member (hereinafter referred to as “other ring member”) provided in the other mold, and the other metal mold is formed by the water channel. It is conceivable to lower the temperature of the mold body of the mold (hereinafter referred to as “second means”).
JP 2000-218670 A

  However, in the first means, even if the temperature of the temperature control water of the other mold is set to be low, the ring members are brought into contact with each other at the time of clamping, so that the injection molding is continued. In the process, heat is conducted from the ring member (hereinafter referred to as “one ring member”) provided in the one mold at a high temperature to the other ring member, and the other ring member By raising the temperature, the other ring member may be thermally expanded and deformed outward in the radial direction. In this case, a gap is formed between the outer peripheral surface of the mold body of the other mold (hereinafter referred to as “the other mold main body”) and the inner peripheral surface of the other ring member, and is melted during the injection. The resin enters the gap and solidifies in this state to form an injection molded product. That is, there is a possibility that burrs extending in a direction perpendicular to the surface of the molded product may occur at the outer peripheral edge of the injection molded product.

  On the other hand, in the second means, the cooling water channel makes it possible to reliably maintain the temperatures of both the other mold body and the other ring member lower than those of the one mold, It is possible to improve the manufacturing efficiency, and it is possible to prevent the temperature of the other ring member from becoming higher than that of the other mold body, thereby preventing the occurrence of the burr in the injection molded product. On the other hand, due to the contact of the ring members during mold clamping, the heat of the one ring member is taken away by the cooling water channel via the other ring member, and as a result, the injection As a result, the temperature of the molten resin in the part and the temperature of the transfer uneven part of the stamper part are lowered, and the molding defect may occur. That is, it becomes difficult to spread the molten resin over the entire area of the stamper portion including the transfer uneven portion, and a molding defect including the formation of the information recording uneven portion occurs. There was a fear.

  The present invention has been made in view of the above problems, and provides an injection mold apparatus that can improve the manufacturing efficiency while preventing the occurrence of molding defects in a thin plate-like injection molded product. The purpose is to do.

  In order to solve such problems and achieve the above-mentioned object, the injection mold apparatus of the present invention is provided so as to be able to approach and separate, and a pair of cavities are formed between the mold surfaces in a clamped state. One mold is solidified in a state in which the molten resin in the cavity is in contact with the molten resin in the cavity, so that the surface of the injection molded product is solidified. A stamper portion configured to form an uneven portion for recording information, and each of the pair of molds includes a mold body having the mold surface, and an outer peripheral portion of these mold bodies. Each of the ring members is fitted to each other, and when the mold is clamped, a pair of the ring members abut against each other, so that at least the mold surface and the inner peripheral surface of the ring member in the other mold are used. Wherein at least one of the pair of ring members is disposed on a contact surface that contacts the other ring member in the clamped state. The first recess is formed in a non-contact manner with the ring member.

According to the present invention, since the first recessed portion is formed on the contact surface of at least one of the pair of ring members, the contact area where the pair of ring members contact each other during mold clamping is minimized. Even when the mold temperature of the other mold is set to be lower than that of the one mold, the ring member in the one mold is clamped when the mold is clamped. It is possible to suppress the heat of (hereinafter referred to as “one ring member”) from being conducted to the ring member (hereinafter referred to as “the other ring member”) in the other mold. Therefore, it becomes possible to minimize the amount of thermal expansion deformation of the other ring member toward the radially outer side, and the inner peripheral surface of the other ring member and the mold body in the other mold It can suppress that the clearance gap between the outer peripheral surfaces of this is expanded. As a result, the molten resin enters the gap during the injection, and solidifies in this state to form an injection molded product, so that the outer peripheral edge of the injection molded product is perpendicular to the surface of the molded product. It is possible to prevent the occurrence of extended burrs.
Further, when the mold is clamped, the first recessed portion is closed by the contact surface facing the first recessed portion, so that an air heat insulating layer is formed between the pair of ring members. Therefore, the heat conduction can be surely suppressed.
As described above, it is possible to improve the production efficiency while preventing the occurrence of defective molding of the thin injection-molded product.

  The mold apparatus for injection molding according to the present invention is provided with a pair of molds that are provided so as to be able to approach and separate, and in which a cavity is formed between mold surfaces in a clamped state. An injection part for injecting molten resin into the cavity, and a stamper configured to form an uneven part for recording information on the surface of the injection-molded product by solidifying the molten resin in the cavity in contact with the stamper And each of the pair of molds includes a mold body having the mold surface, and ring members are individually fitted to the outer peripheral parts of these mold bodies, An injection mold in which the cavity is defined by at least the mold surface and the inner peripheral surface of the ring member in the other mold when the pair of ring members are in contact with each other. Dress And at least one of the pair of ring members includes a contact portion having a contact surface that contacts the other ring member in the clamping state, and extends radially outward from an outer peripheral surface of the contact portion. And a fin which is not in contact with the mold body.

According to the present invention, since at least one of the ring members includes the contact portion and the fin, the temperature of the ring member in the mold including the ring member and the mold main body is increased. Can be reduced in a limited manner. That is, in the one mold in which the injection part and the like are provided and the mold temperature is set to a high temperature, the ring member (hereinafter referred to as “one ring member”) is provided with the fins. The heat of the member can be dissipated to the outside through the fins. Therefore, it becomes possible to reduce only the temperature of the one ring member in a limited manner while maintaining the temperature of the mold main body in the one mold at a high temperature, and from the one ring member at the time of mold clamping, Heat conduction to the ring member in the other mold (hereinafter referred to as “the other ring member”) can be suppressed.
On the other hand, if the fin is provided in the other ring member of the other mold in which the mold temperature not provided with the injection portion or the like is set to a low temperature, the one ring member is separated from the one ring member during the mold clamping. The heat conducted to the other ring member can be dissipated to the outside through the fin, and the temperature increase of the other ring member can be suppressed.
As described above, even when the mold temperature of the other mold is set lower than that of one mold, the inner peripheral surface of the other ring member and the outer peripheral surface of the mold main body in the other mold It is possible to prevent the gap between them from expanding, and to prevent the occurrence of the burrs in the injection molded product, while preventing the occurrence of molding defects in the injection molded product made into a thin plate, The production efficiency can be improved.

  The mold apparatus for injection molding according to the present invention is provided with a pair of molds that are provided so as to be able to approach and separate, and in which a cavity is formed between mold surfaces in a clamped state. An injection part for injecting molten resin into the cavity, and a stamper configured to form an uneven part for recording information on the surface of the injection molded product by solidifying the molten resin in the cavity in contact with the stamper Each of the pair of molds includes a mold body having the mold surface, and a ring member is fitted to each of the outer peripheral parts of these mold bodies. An injection mold in which the cavity is defined by at least the mold surface and the inner peripheral surface of the ring member in the other mold when the pair of ring members abut against each other. Dress And at least one of a pair of said ring members is set as the structure by which the 1st heat insulating material was arrange | positioned by the contact surface contact | abutted with the said other ring member in the said mold clamping state, It is characterized by the above-mentioned. To do.

  According to the present invention, since the first heat insulating material is disposed on the contact surface of at least one of the pair of ring members, the mold temperature of the other mold is higher than that of the one mold. Even when set low, it is possible to suppress the conduction of heat from the ring member in the one mold to the ring member in the other mold (hereinafter referred to as “the other ring member”) during mold clamping. It becomes possible. Therefore, it becomes possible to suppress a gap between the inner peripheral surface of the other ring member and the outer peripheral surface of the mold body in the other mold, and the burrs are generated in the injection molded product. Thus, it is possible to improve the production efficiency while preventing the occurrence of molding defects in the injection-molded product having a thin plate shape.

  The mold apparatus for injection molding according to the present invention is provided with a pair of molds that are provided so as to be able to approach and separate, and in which a cavity is formed between mold surfaces in a clamped state. An injection part for injecting molten resin into the cavity, and a stamper configured to form an uneven part for recording information on the surface of the injection molded product by solidifying the molten resin in the cavity in contact with the stamper And each of the pair of molds includes a mold body having the mold surface, and ring members are individually fitted to the outer peripheral parts of these mold bodies, An injection mold in which the cavity is defined by at least the mold surface and the inner peripheral surface of the ring member in the other mold when the pair of ring members are in contact with each other. Dress A is, between the mold body and the ring member in the one mold and the second heat insulating material, characterized in that it is arranged.

  According to the present invention, in the one mold provided with the injection section and the stamper section and set at a high mold temperature, the ring member (hereinafter referred to as “one ring member”) and the mold Since the second heat insulating material is provided between the mold body (hereinafter referred to as “one mold body”), heat is conducted from the one mold body to be heated to the one ring member. This can be suppressed, and an increase in the temperature of the one ring member can be suppressed. Therefore, even if the one mold body is set at a higher temperature than the mold body in the other mold (hereinafter referred to as “the other mold body”), When the ring members come into contact with each other, it is possible to suppress heat conduction from the one ring member to the ring member in the other mold (hereinafter referred to as “the other ring member”), The temperature rise of the other ring member can be minimized. As a result, it is possible to suppress an increase in temperature difference between the other ring member and the other mold body, and the inner peripheral surface of the other ring member and the outer periphery of the other mold body. It can suppress that the clearance gap between surfaces expands.

  The mold apparatus for injection molding according to the present invention is provided with a pair of molds that are provided so as to be able to approach and separate, and in which a cavity is formed between mold surfaces in a clamped state. An injection part for injecting molten resin into the cavity, and a stamper configured to form an uneven part for recording information on the surface of the injection molded product by solidifying the molten resin in the cavity in contact with the stamper And each of the pair of molds includes a mold body having the mold surface, and ring members are individually fitted to the outer peripheral parts of these mold bodies, An injection mold in which the cavity is defined by at least the mold surface and the inner peripheral surface of the ring member in the other mold when the pair of ring members are in contact with each other. Dress And at least one of each contact surface of the said one metal mold | die which the said ring member and the said mold main body mutually contact is formed with the 2nd dent part which does not contact the other contact surface. It is characterized by that.

According to the present invention, in the one mold in which the injection part and the stamper part are provided and the mold temperature is set to a high temperature, each of the contact surfaces of the ring member and the mold body that are in contact with each other. Since at least one of the second recesses that is not in contact with the other contact surface is formed, it is possible to minimize the contact area between the ring member and the mold body, and the one mold Heat conduction from a mold body (hereinafter referred to as “one mold body”) in the mold to the ring member (hereinafter referred to as “one ring member”) of the mold can be suppressed. Therefore, it is possible to suppress the temperature increase of the one ring member, and the one mold body is compared with the mold body in the other mold (hereinafter referred to as “the other mold body”). Even when the pair of ring members are in contact with each other at the time of mold clamping, the ring member in the other mold from the one ring member (hereinafter referred to as “the other ring member”) Therefore, it is possible to suppress the conduction of heat, and the temperature increase of the other ring member can be minimized. As a result, it is possible to suppress an increase in temperature difference between the other ring member and the other mold body, and the inner peripheral surface of the other ring member and the outer periphery of the other mold body. It can suppress that the clearance gap between surfaces expands.
In addition, since the second recessed portion is closed by the contact surface facing the second recessed portion, an air heat insulating layer is formed between the one mold body and the one ring member. It becomes possible to suppress the conduction of heat.

  ADVANTAGE OF THE INVENTION According to this invention, improvement of manufacturing efficiency can be aimed at, preventing generation | occurrence | production of the shaping | molding defect of the injection molded product made into thin plate shape.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2. The mold apparatus for injection molding 10 shown in these drawings is provided with a pair of molds 12 and 13 which are provided so as to be able to approach and separate and in which a cavity 11 is formed between mold surfaces 12a and 13a in a clamped state. The pair of molds 12 and 13 includes a fixed mold 12 and a movable mold 13 supported so as to be movable forward and backward with respect to the mold surface 12a of the fixed mold 12. The fixed mold 12 is solidified in a state in which the sprue bush (injection portion) 14 for injecting molten resin into the cavity 11 and the molten resin in the cavity 11 are in contact with each other, so that the surface of the injection molded product can be used for information recording. A stamper portion 15 (see FIG. 2) configured to form an uneven portion is provided.

  The stamper portion 15 includes a disk portion, and is detachably attached to the fixed mold 12 with the upper surface of the disk portion being in contact with the fixed mold surface 12a. A transfer concavo-convex portion for forming the concavo-convex portion in the injection-molded product is formed on the lower surface of the disc portion facing the cavity 11. Further, the disk portion of the stamper portion 15 is attached to the fixed mold 12 so as to cover the fixed mold surface 12a over the entire region, and the movable mold surface 13a is arranged so that the substantially entire region thereof faces the transfer uneven portion. Has been. Hereinafter, both the surface of the transfer concavo-convex portion and the fixed mold surface 12a will be referred to as a “fixed mold surface 12a”.

  Each of the pair of molds 12 and 13 includes mold main bodies 12b and 13b having the mold surfaces 12a and 13a, and ring members 20 and 30 are separately provided on the outer peripheral portions of the mold main bodies 12b and 13b. It is set as the structure fitted. In addition, between the inner peripheral surface of the ring member 30 (hereinafter referred to as “movable-side ring member”) 30 of the movable mold 13 and the outer peripheral surface of the mold body (hereinafter referred to as “movable mold main body”) 13b of the movable mold 13. A slide bearing 36 is provided, and the movable ring member 30 is fitted to the movable main body 13b via the slide bearing 36.

  In these ring members 20 and 30, the surfaces facing each other are such that the mold surfaces 12a and 13a in the respective molds 12 and 13 provided with the ring members 20 and 30 respectively, and the other mold surfaces 12a and 13a. The pair of mold surfaces 12a and 13a are not in contact with each other in the mold-clamped state, and the surfaces of the ring members 20 and 30 facing each other (hereinafter referred to as “apertures”). 20a and 30a are in contact with each other. The ring members 20 and 30 are made of the same material as the fitted mold main bodies 12b and 13b, respectively.

A sprue bushing 14 is disposed inside the fixed mold main body 12b. A sprue 14a is formed in the bushing 14 so as to penetrate the central portion in the radial direction from the upper end surface to the lower end surface in the axial direction. ing. The upper end of the sprue 14a is connected to a nozzle of an injection molding machine (not shown), and the lower end is configured to open to the fixed mold surface 12a. Here, the disk portion of the stamper portion 15 is formed with a hole in the central portion in the radial direction, and the outer peripheral surface of the lower end portion of the sprue bush 14 is inserted into the hole. As described above, the molten resin is supplied into the cavity 11 from the nozzle of the injection molding machine through the sprue 14a.
Note that a heater (not shown) is provided around the sprue bushing 14 inside the fixed mold body 12b.

In addition to the movable mold main body 13b and the movable ring member 30, the movable mold 13 is supported by a receiving portion 13c from which the movable mold main body 13b is supported from the lower surface side, and the receiving portion 13c is supported from the lower surface side. And an attachment portion (not shown). The attachment portion is attached to a movable platen of an injection molding machine (not shown). In addition, the temperature control water path which is not illustrated is formed in the movable type main body 13b.
The movable body 13b and the receiving portion 13c are formed into a cylindrical body and a cooling channel 17a into which a refrigerant is supplied is formed to cool the molten resin in the cavity 11. A cooling member 17 is provided.

The cooling member 17 is formed with a through-hole penetrating in the axial direction in the center portion in the radial direction. A cylindrical projecting sleeve 26 is inserted into the through-hole, and an inner peripheral surface of the through-hole. A slide bearing 27 is disposed between the protruding sleeve 26 and the outer peripheral surface of the protruding sleeve 26, so that the protruding sleeve 26 can slide in the mold opening / closing direction independently of the cooling member 17.
A cylindrical gate cut sleeve 28 is inserted into the protruding sleeve 26, and a slide bearing 27 is disposed between the inner peripheral surface of the protruding sleeve 26 and the outer peripheral surface of the gate cut sleeve 28. As a result, the gate cut sleeve 28 can slide in the mold opening / closing direction independently of the protruding sleeve 26. Further, a cylindrical protruding pin 29 is inserted and arranged inside the gate cut sleeve 27.

Here, the gate cut sleeve 28 is supported by a first drive unit (not shown) so as to be able to advance and retreat in the mold opening / closing direction. It is a supported configuration. When the upper surface of the protruding sleeve 26, the gate cut sleeve 28, and the protruding pin 29 is the central portion in the radial direction of the movable mold surface 13a, that is, the optical disk manufactured by the apparatus 10, the disk is reproduced by, for example, a reproducing apparatus. In addition, a movable mold surface 13a is formed on which a clamp portion sandwiched by the reproducing apparatus is formed.
As described above, when these members 26, 28, and 29 are moved forward with respect to the cavity 11, the movable mold surface 13 a that is substantially flush with the central portion in the radial direction excludes the central portion. It will protrude from the other part.

Hereinafter, the ring members 20 and 30 of the present embodiment will be described.
First, a ring member 20 (hereinafter referred to as “fixed ring member”) 20 of the fixed mold 12 is radially outward from a fixed contact portion 21 having the contact surface 20a and an outer peripheral surface of the contact portion 21. An extending fin 22 is provided, and these 21 and 22 are integrally formed. As shown in FIG. 2, the fin 22 of this embodiment is not in contact with not only the movable mold 13 side but also with the fixed mold body 12 b, and the fin 22 itself is not in contact with other members. That is, the fixed-side ring member 20 has a configuration in which the outer peripheral edge portions of the front and back surfaces are recessed in the thickness direction of the ring member 20 over the entire periphery including the outer peripheral edge of the ring member 20. The outer peripheral edge portion constitutes the fin 22.

  As described above, the fixed-side ring member 20 includes the fixed-type main body 12b in a state where the portion excluding the fins 22, that is, the back surface (hereinafter referred to as “contact surface”) 21a of the fixed-side contact portion 21 is in contact with the fixed-type main body 12b. And the surface of the fixed-side contact portion 21 (hereinafter referred to as “fixed-side contact surface”) 20a is in contact with the contact surface of the movable-side ring member 30 (hereinafter referred to as “movable-side contact”). 30a) (referred to as “contact surface”).

  As shown in FIG. 2, the fixed-side contact surface 20a of the present embodiment has a fixed-side first recess 23 that is in non-contact with the movable-side contact surface 30a in the clamped state. It is formed continuously or intermittently over the entire circumference. The contact surface 21a is formed with a second indentation 24 that is not in contact with the fixed mold body 12b continuously or intermittently over the entire circumference of the contact surface 21a.

Next, the movable ring member 30 extends from the movable inner contact portion 31 having the contact surface 30 a to the radially inner edge of the corresponding contact portion 31 in the radial direction and is separated from the fixed mold 12. And a rising portion 33 that rises from the surface of the relief portion 32 toward the fixed mold 12 from the radially inner peripheral edge of the relief portion 32.
With the movable ring member 30 attached to the movable mold 13b, at least the movable contact surface 30a and the upper surface 33a of the rising portion 33 are fixed to the fixed mold 12 rather than the movable mold surface 13a, as shown in FIG. It is positioned to protrude to the side. Further, the positions of the inner peripheral edges of the movable contact surface 30a and the fixed contact surface 20a in the radial direction are substantially the same, and the outer periphery of the movable contact surface 30a is the fixed contact surface 20a. In other words, the entire movable contact surface 30a is in contact with the fixed contact surface 20a during mold clamping. In this movable side contact surface 30a, in a mold clamping state, in a position different from the formation position of the fixed-side first dent 23, in the present embodiment, at a position radially outward from the first dent 23. A movable first dent 34 that is not in contact with the fixed contact surface 20a is formed.
In addition, as shown in FIG. 2, the transfer concavo-convex portion of the stamper portion 15 provided in the fixed mold 12 extends radially outward from the radial central portion, and the outer peripheral edge thereof is The upper surface 33 a of the rising portion 33, that is, the inner peripheral edge of the movable ring member 30 is positioned radially outward. That is, the upper surface 33 a of the rising portion 33 is opposed to the transfer uneven portion of the stamper portion 15.

As described above, the rising portion 33 is positioned so as to protrude from the movable mold surface 13a toward the fixed mold 12, but in the clamped state, the upper surface 33a of the rising portion 33 is not in contact with the fixed mold surface 12a. Thus, the transfer uneven portion of the stamper portion 15 is not damaged by the rising portion 33. The size of the gap between the upper surface 33a of the rising portion 33 and the fixed mold surface 12a in the clamped state is such that the molten resin injected into the cavity 11 does not flow out from the gap toward the escape portion 32. It is set so that only gas generated from the gas flows out. That is, the molten resin injected into the cavity 11 via the sprue 14a moves outward in the radial direction until it contacts the inner peripheral surface of the rising portion 33 (the inner peripheral surface of the movable ring member 30). It is supposed to be. In other words, the inner peripheral surface of the rising portion 33 forms the inner peripheral surface of the injection molded product.
A hole 12c formed in the fixed mold surface 12a at a position facing the escape portion 32 via the stamper portion 15 is an air suction hole 12c for vacuum-sucking the stamper portion 15 to the fixed mold body 12b. Has been.

  Here, the movable side ring member 30 is configured to be urged toward the fixed mold 12 by the urging member 35 disposed in the receiving portion 13c. By the biasing member 35 and the slide bearing 36, when the mold is clamped, the fixed side contact surface 20a of the fixed side ring member 20 and the movable side contact surface 30a of the movable side ring member 30 contact each other. The movable ring member 30 slides in a direction away from the fixed mold 12 in the mold opening / closing direction, and the impact force at this time is relieved.

A method of manufacturing a thin plate-like injection molded product by the injection molding die apparatus 10 configured as described above will be described.
First, the movable mold 13 is moved forward toward the fixed mold 12, the movable contact surface 30a is brought into contact with the fixed contact surface 20a, and the mold is clamped, and the mold surfaces 12a and 13a and the movable ring member 30 are moved. Cavity 11 defined by the inner peripheral surface of is formed. Here, in the present embodiment, the mold temperature of the fixed mold body 12b provided with the sprue bush 14 and the stamper portion 15 is set to be about 5 ° C. to about 20 ° C. higher than that of the movable mold body 13b, and the injection to be formed. The shape of the transfer concavo-convex portion of the stamper portion 15 is reliably transferred to the surface of the molded product, and the molten resin in the cavity 11 is cooled and solidified at an early stage.

  The molten thermoplastic resin is injected into the cavity 11 from the nozzle of the injection molding machine through the sprue 14a. Thereafter, the gate cut sleeve 28 and the projecting pin 29 of the movable mold 13 are moved forward and engaged with the sprue 14a that opens to the fixed mold surface 12a, thereby blocking the communication state between the sprue 14a and the cavity 11. At this time, a through hole is formed in the central portion in the radial direction of the resin in the cavity 11. Further, substantially the entire movable mold 13 is further moved forward toward the fixed mold 12, the clamping force of the fixed mold 12 and the movable mold 13 is increased, and the resin in the cavity 11 is compressed. Holding in this state for a predetermined time, the resin in the cavity 11 is cooled and solidified to form a thin plate-like injection molded product. At this time, the resin in the sprue 14 a is solidified in a state where it is adhered to the upper surfaces of the gate cut sleeve 28 and the protruding pin 29.

  Next, the movable mold 13 is moved backward, and the resin solidified in the injection molded product and the sprue 14a is separated from the fixed mold 13 and the mold is opened. The resin solidified in step 1 is pulled away from the upper surfaces of the gate cut sleeve 28 and the protrusion pin 29. Further, the protruding sleeve 26 is moved forward, and the upper peripheral surface of the injection molded product in contact with the movable mold surface 13a is pushed up toward the fixed mold 12 by the upper surface thereof, and the entire injection molded product Is pulled away from the movable mold surface 13a, and an injection molded product is taken out from the apparatus 10.

  As described above, according to the injection mold apparatus 10 according to the present embodiment, the fixed-side first recess 23 is formed on the fixed-side contact surface 20a, and the movable-side first surface is formed on the movable-side contact surface 30a. Since the recessed portion 34 is formed, it is possible to minimize the contact area where the ring members 20 and 30 are in contact with each other during mold clamping, and the movable mold body as in this embodiment. Even when the mold temperature of 13b is set lower than that of the fixed mold body 12b, it is possible to suppress the heat of the fixed ring member 20 from being conducted to the movable ring member 30 during the mold clamping. Therefore, it is possible to minimize the amount of thermal expansion deformation of the movable side ring member 30 in the radially outward direction, and the inner peripheral surface of the movable side ring member 30 and the outer peripheral surface of the movable main body 13b. It can suppress that the clearance gap between them expands. As a result, the molten resin enters the gap during the injection, and solidifies in this state to form an injection molded product, so that the outer peripheral edge of the injection molded product is perpendicular to the surface of the molded product. It is possible to prevent the occurrence of extended burrs.

Further, when the mold is clamped, the first recesses 23 and 34 are closed by the contact surfaces 20a and 30a facing the first recesses 23 and 34, so that the pair of ring members 20 , 30 can be formed between the heat insulation layers 30 and the heat conduction can be reliably suppressed.
As described above, it is possible to improve the production efficiency while preventing the occurrence of defective molding of the thin injection-molded product.

  Furthermore, in this embodiment, since the stationary-side ring member 20 includes the fins 22, the temperature of the stationary-side ring member 20 is limitedly reduced among the stationary mold 12 including the ring member 20 and the stationary mold body 12b. It becomes possible. That is, in the fixed mold 12 provided with the sprue bush 14 and the stamper portion 15 and the mold temperature is set to a high temperature, when the fin 22 is provided on the fixed ring member 20, the heat of the ring member 20 is transferred to the fin 22. It is possible to dissipate to the outside. Therefore, it is possible to reduce only the temperature of the fixed ring member 20 in a limited manner while maintaining the temperature of the fixed mold body 12b at a high temperature, and heat is transferred from the fixed ring member 20 to the movable ring member 30. Conduction can be suppressed. Thereby, it can suppress reliably that the clearance gap between the internal peripheral surface of the movable side ring member 30 and the outer peripheral surface of the movable type main body 13b expands.

Furthermore, in the present embodiment, the contact surface 21a of the stationary ring member 20 in the stationary mold 12 set to the high temperature is formed with a second recess 24 that is not in contact with the stationary mold body 12b. It becomes possible to suppress the contact area between the ring member 20 and the fixed mold body 12b to a minimum, and heat conduction from the fixed mold body 12b to the fixed ring member 20 can be suppressed. Therefore, it becomes possible to suppress the temperature rise of the fixed ring member 20, and even if the fixed mold main body 12b is set at a higher temperature than the movable mold main body 13b, the fixed ring member 20 is fixed during the mold clamping. When the movable ring member 30 and the movable ring member 30 come into contact with each other, it is possible to suppress the conduction of heat from the fixed ring member 20 to the movable ring member 30, and the temperature rise of the movable ring member 30 is minimized. It can be. This makes it possible to suppress an increase in the temperature difference between the movable ring member 30 and the movable mold body 13b, and between the inner circumferential surface of the movable ring member 30 and the outer circumferential surface of the movable mold body 13b. It is possible to reliably suppress an increase in the gap.
Further, since the second recessed portion 24 is blocked by the contact surface 21a facing the second recessed portion 24, an air heat insulating layer is formed between the fixed mold body 12b and the fixed-side ring member 20. It becomes possible to suppress the conduction of heat.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, the configuration in which the fins 22 are disposed on the stationary ring member 20 is shown. However, the fins 22 may be disposed on the movable ring member 30, or may be disposed on both the ring members 20, 30. Also good. Even when the fin 22 is disposed on the movable ring member 30, the heat conducted from the fixed ring member 20 can be dissipated to the outside through the fin 22. The rise can be suppressed.

Further, instead of the above embodiment, as shown in FIG. 3, a material that forms the fixed ring member 20 and the movable ring member 30 on at least one of the fixed contact surface 20a and the movable contact surface 30a is used. You may arrange | position the 1st heat insulating material 41 which consists of material (for example, glass fiber) with low heat conductivity. Even in this case, it is possible to suppress heat conduction from the fixed contact surface 20a to the movable contact surface 30a. Further, as shown in FIG. 3, the thermal conductivity is lower than the material forming the stationary ring member 20 and the stationary mold body 12b between the contact surface 21a of the stationary ring member 20 and the stationary mold body 12b. You may arrange | position the 2nd heat insulating material 42 which consists of material (for example, glass fiber). Even in this case, it is possible to suppress heat conduction from the stationary mold body 12b to the stationary ring member 20, and to fix the fin 22 to the fin 22 even if the contact surface 21a and the upper surface of the fin 22 are flush with each other. It is possible to make the mold body 12b non-contact.
In FIG. 3, the second heat insulating material 42 is disposed between the contact surface 21 a of the stationary ring member 20 and the stationary body 12 b, but the inner peripheral surface 20 b of the stationary ring member 20 and the stationary mold are arranged. The second heat insulating material 42 may be disposed between the contact surface 21a and the inner peripheral surface 20b of the stationary ring member 20 and the stationary mold body 12b. May be.

Furthermore, not limited to the above embodiment, if at least one of the recesses 23, 24, 30 and the heat insulating materials 41, 42 is provided, heat is generated from the fixed ring member 20 to the movable ring member 30. Can be prevented from conducting.
Moreover, although the 1st, 2nd dent parts 23, 34, and 24 were formed over the perimeter of the said contact surfaces 20a and 30a, not only this but the structure extended in radial direction may be sufficient, Or it is good also as a dot-like dent part.

  Furthermore, in the said embodiment, the structure which formed the 2nd recessed part 24 only in the back surface of the stationary-side contact part 21, ie, the said contact surface 21a, among the surfaces of the stationary-side ring member 20 which contacts the stationary mold main body 12b. Although shown, if it is the surface of the stationary-side ring member 20 that faces the stationary mold main body 12b, the portion that forms the second recessed portion 24 is not limited. That is, for example, in FIG. 2, the second recessed portion 24 may be formed on the inner peripheral surface 20b of the stationary ring member 20, and the second recessed portion is formed on both the inner circumferential surface 20b of the stationary ring member 20 and the contact surface 21a. The portion 24 may be formed.

  The production efficiency can be improved while preventing the occurrence of molding defects in the injection-molded product having a thin plate shape.

It is sectional drawing which shows the outline of the mold apparatus for injection molding shown as one Embodiment of this invention. In the injection mold apparatus shown in FIG. 1, it is a principal part enlarged view of 1st Embodiment of this invention. In the mold apparatus for injection molding shown in FIG. 1, it is the principal part enlarged view of 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Injection mold apparatus 11 Cavity 12 Fixed mold 12a Fixed mold surface 12b Fixed mold main body (mold main body)
13 Movable mold 13a Movable mold surface 13b Movable mold body (mold body)
14 Sprue bushing (injection part)
DESCRIPTION OF SYMBOLS 15 Stamper part 20 Fixed side ring member 22 Fin 23, 34 1st recessed part 24 2nd recessed part 30 Movable side ring member 41 1st heat insulating material 42 2nd heat insulating material

Claims (5)

A pair of molds provided so as to be able to approach and separate and in which a cavity is formed between the mold surfaces in a clamped state is provided, one of the molds includes an injection unit that injects molten resin into the cavity, and A stamper portion configured to form an uneven portion for recording information on the surface of an injection molded product by solidifying the molten resin in the cavity in contact with the surface; and
Each of the pair of molds includes a mold body having the mold surface, and ring members are fitted to the outer peripheral portions of these mold bodies.
An injection molding in which the cavity is defined by at least the mold surface and the inner peripheral surface of the ring member in the other mold when the pair of ring members abut with each other during mold clamping. Mold equipment,
At least one of the pair of ring members has a configuration in which a first recess portion that is in non-contact with the other ring member is formed on a contact surface that contacts the other ring member in the clamped state. An injection mold apparatus characterized by the above. A pair of molds provided so as to be able to approach and separate and in which a cavity is formed between the mold surfaces in a clamped state is provided, one of the molds includes an injection unit that injects molten resin into the cavity, and A stamper portion configured to form an uneven portion for recording information on the surface of an injection molded product by solidifying the molten resin in the cavity in contact with the surface; and
Each of the pair of molds includes a mold body having the mold surface, and ring members are fitted to the outer peripheral portions of these mold bodies.
An injection molding in which the cavity is defined by at least the mold surface and the inner peripheral surface of the ring member in the other mold when the pair of ring members abut with each other during mold clamping. Mold equipment,
At least one of the pair of ring members includes a contact portion having a contact surface that contacts the other ring member in the clamped state, and extends radially outward from an outer peripheral surface of the contact portion; and An injection mold apparatus comprising a fin that is not in contact with the mold body. A pair of molds provided so as to be able to approach and separate and in which a cavity is formed between the mold surfaces in a clamped state is provided, one of the molds includes an injection unit that injects molten resin into the cavity, and A stamper portion configured to form an uneven portion for recording information on the surface of an injection molded product by solidifying the molten resin in the cavity in contact with the surface; and
Each of the pair of molds includes a mold body having the mold surface, and ring members are fitted to the outer peripheral portions of these mold bodies.
An injection molding in which the cavity is defined by at least the mold surface and the inner peripheral surface of the ring member in the other mold when the pair of ring members abut with each other during mold clamping. Mold equipment,
At least one of the pair of ring members has a configuration in which a first heat insulating material is disposed on a contact surface that contacts the other ring member in the clamped state. Mold equipment. A pair of molds provided so as to be able to approach and separate and in which a cavity is formed between the mold surfaces in a clamped state is provided, one of the molds includes an injection unit that injects molten resin into the cavity, and A stamper portion configured to form an uneven portion for recording information on the surface of an injection molded product by solidifying the molten resin in the cavity in contact with the surface; and
Each of the pair of molds includes a mold body having the mold surface, and ring members are fitted to the outer peripheral portions of these mold bodies.
An injection molding in which the cavity is defined by at least the mold surface and the inner peripheral surface of the ring member in the other mold when the pair of ring members abut with each other during mold clamping. Mold equipment,
An injection mold apparatus, wherein a second heat insulating material is disposed between the ring member and the mold main body of the one mold. A pair of molds provided so as to be able to approach and separate and in which a cavity is formed between the mold surfaces in a clamped state is provided, one of the molds includes an injection unit that injects molten resin into the cavity, and A stamper portion configured to form an uneven portion for recording information on the surface of an injection molded product by solidifying the molten resin in the cavity in contact with the surface; and
Each of the pair of molds includes a mold body having the mold surface, and ring members are fitted to the outer peripheral portions of these mold bodies.
An injection molding in which the cavity is defined by at least the mold surface and the inner peripheral surface of the ring member in the other mold when the pair of ring members abut with each other during mold clamping. Mold equipment,
In the one mold, at least one of the contact surfaces of the ring member and the mold main body that are in contact with each other is formed with a second recessed portion that is not in contact with the other contact surface. Injection mold equipment.

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