JP2010089390A - Molding die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding die of high cooling efficiency by arranging a cooling medium passage effectively at points to be cooled. <P>SOLUTION: The molding die with a male mold and a female mold clamped to carry out resin molding includes a plurality of lateral holes provided inward from the side face of at least one of the male mold and female mold so as not to intersect inside the mold, and a connection part machined at a mounting surface of the die to connect the plurality of lateral holes and to form the cooling medium passage. The degree of freedom in arranging the cooling medium passage is thereby increased, and cooling efficiency can be enhanced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a molding die used for manufacturing a resin molded product.

  In resin molding such as injection molding and mold press molding, after a molten resin is filled into a cavity of a molding die, heat is removed from the molten resin to fix the shape of the resin, and a predetermined molded product is manufactured. Therefore, the cooling system that cools the mold using the cooling medium is an important factor that affects the quality of the molded product.

  Patent Document 1 describes a synthetic resin molding die having a structure in which the entire cavity is nested and thermally insulated from the mother die. The purpose of this molding die is to control the temperature of the cavity in a short time by alternately flowing the heating medium and the cooling medium through the flow path of the cooling medium formed in the insert. This facilitates filling and cooling of the molten resin into a complicated cavity having a thin part and a thick part, and can eliminate defects generated on the surface of the molded product.

JP 2001-18229 A

  Hereinafter, problems to be solved by the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic view showing a cross section of a molding die. A fixed mold 2 that is a female mold and a movable mold 3 that is a male mold are clamped. In the stationary mold 2, the stationary mold 2c is set on the stationary mounting plate 2a. Further, the fixed mold 2 is provided with a locating ring 17 for connecting a nozzle of an injection machine (not shown), and a spool 4 into which molten resin is injected from the injection machine is provided at the center of the locating ring. The spool bush 2b on which the spool 4 is formed is configured to be inserted from the outside into the fixed mounting plate 2a, and can be removed and replaced.

  On the other hand, in the movable-side mold 3, a receiving plate 3c is attached to the movable-side mounting plate 3a via a spacer block 3b, and the movable-side mother die 3d and the core die 3e are fixed to the receiving plate 3c. Further, an ejector pin 10, a spool lock pin 12, and a return pin 13 sandwiched between the ejector plates 14 and 15 are disposed in the space between the movable side mounting plate 3 a and the receiving plate 3 c. As will be described later, when the molding is completed, the mold is opened, and the molded product is taken out, the ejector rod of the ejector device provided in the molding machine (not shown) passes through the ejector hole 18 upward the ejector plate 14, 15 is pushed up and the molded product is taken out.

  As shown in FIG. 1, when the guide pin 16a is engaged with the guide pin bush 16b and the fixed side mother die 2c, the movable side mother die 3d and the core die 3e are clamped, the runner 5 communicated with the spool 4 is obtained. And the gate 6 and the cavity C are formed. In this mold clamping state, molten resin is injected from an injection machine (not shown), and the cavity C is filled through the spool 4, the runner 5 and the gate 6.

  The molten resin filled in the cavity C is deprived of heat by the core mold 3e and the fixed-side mother mold 2c cooled by the cooling medium circulating in the horizontal hole 7, and becomes a molded product having a predetermined shape. When cooling of the molten resin is completed and the shape of the resin is fixed, the mold is opened and the ejector rod of the ejector device (not shown) pushes up the ejector plates 14 and 15. As a result, the ejector pin 10 is pushed upward, and the molded product molded in the cavity C is separated from the core mold 3e. On the other hand, the spool lock pin 12 is filled in the spool 4, the runner 5, and the gate 6 and hardened. The resin is pushed upward and separated from the movable side mold 3d and taken out of the mold.

  As described above, in the resin molding described above, the cooling of the core mold 3e and the fixed-side mother mold 2c by the cooling medium flowing through the lateral hole 7 is an important factor that affects the quality of the molded product. Further, the time required for cooling the molten resin affects the length of the cycle time of the molding process, and is a factor that determines work efficiency.

  However, since the molding die has a complicated configuration, there is a problem that a region where the flow path of the cooling medium can be processed is limited. In particular, the core mold 3e in which a plurality of ejector pins 10 are disposed in the plane of the cavity C has a problem that a space for processing the flow path is small and the flow path may not be set at a point to be cooled. It was.

  FIG. 2 is a diagram schematically showing the arrangement of the ejector pins 10 of the core mold 3e and the configuration of the flow path F of the cooling medium. The number of ejector pins 10 necessary to push up the molded product and separate it from the core mold 3e is arranged at an optimum position. On the other hand, the horizontal hole 7 which becomes the flow path of the cooling medium is formed by drilling a hole from the side surface of the core mold 3e. Therefore, in order to form the flow path indicated by the arrow F in the figure, the horizontal hole 7 is opened from the direction opposite to A and C, and further the holes processed in the A and C directions are connected by the hole opened from the B direction. There is a need to. The hole processed from the B direction is covered with the cap 21c, and the flow path F is completed.

  In the case shown in FIG. 2, it can be said that there is a relatively wide space in the arrangement of the ejector pins 10 in the A direction and the C direction, and the degree of freedom in processing the lateral hole 7 is high. However, in machining from the B direction, the machining position is limited to the gap between the ejector pins 10 shown in the drawing. For this reason, there is no freedom in moving and setting the flow path F in the left-right direction. That is, when there is a point to be cooled at the left and right positions of the flow path F in the drawing, there is a problem that the cooling medium is removed from the flow path and effective cooling cannot be performed.

  Therefore, in view of the above problems, the present invention has an object to realize a molding die with high cooling efficiency that enables a cooling medium flow path to be accurately disposed at a point to be cooled.

  In order to solve the above-described problems, a molding die according to the present invention is a molding die that performs resin molding by clamping a male die and a female die, and is a die for at least one of a male die and a female die. In order to form a cooling medium flow path by connecting a plurality of horizontal holes that are provided from the side surface of the mold to the inside and that do not intersect with each other inside the mold, the mounting surface of the mold is processed. And a connecting portion.

  According to the present invention, the flow path of the cooling medium is formed by connecting the plurality of horizontal holes that do not intersect inside the mold by the connecting portion. Since the connecting portion is formed by being processed on the mounting surface of the mold so as not to be affected by a structure such as an ejector pin, the degree of freedom for setting the flow path of the cooling medium can be increased. Thereby, it becomes possible to set the flow path of a cooling medium in the point which should be cooled, and can improve cooling efficiency.

  Further, in the molding die according to the present invention, the connecting portion is provided in communication with the nest inserted into the die and the plurality of horizontal holes, and the nest receiving portion for receiving the nest is connected to the plurality of horizontal holes for cooling. And a connection hole provided in the nesting for forming a flow path of the medium.

  According to the present invention, by providing the connection hole in the nest, the flow holes for the cooling medium can be formed by connecting the horizontal holes regardless of the position of the constituent elements of the molding die such as the ejector pin that becomes an obstacle. . Thereby, the freedom degree which sets the flow path of a cooling medium increases, it becomes possible to cool the point which should be cooled directly, and it can improve cooling efficiency.

  In the molding die according to the present invention, the insert receiving portion is characterized in that a draft angle is set so that an opening for receiving the insert is wider than a bottom surface.

  Thereby, when inserting or removing the insert, it is possible to prevent the O-ring attached to the connection portion between the connection hole and the plurality of horizontal holes from being damaged, and to prevent leakage of the cooling medium.

  In the molding die according to the present invention, the connecting portion is formed from the mounting surface of the die toward the cavity where the resin is molded, and a plurality of vertical holes intersecting each of the plurality of horizontal holes and the cavity to be cooled. In the vicinity of the portion, a cooling hole that is formed from the mounting surface of the mold toward the cavity and has a partition that divides the cooling medium introduction path and the discharge path, and a plurality of connecting pipes that communicate the vertical hole and the cooling hole are provided It is characterized by that.

  According to the present invention, since the vertical hole and the cooling hole are communicated with each other by the connecting pipe, the degree of freedom in the position of providing the cooling hole is high, and it is possible to appropriately arrange the cooling hole in the cavity. Therefore, the cooling efficiency can be improved.

  According to the molding die according to the present invention, it is possible to effectively arrange the flow path of the cooling medium at the point to be cooled, and it is possible to realize a molding die with high cooling efficiency.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the drawings.

  FIG. 3 is a schematic diagram showing the arrangement of the core-type eject pins 10 and the flow path of the cooling medium in the molding die according to the present embodiment. The figure shows the core mold 3e viewed from the direction of the mounting surface in contact with the receiving plate 3c. In order to form the horizontal holes 7, holes that become a plurality of horizontal holes 7 are drilled from the side surface of the core mold 3e in the A direction and the C direction shown in the figure. Since these horizontal holes 7 are processed with their positions shifted in the vertical direction in the figure, even if they are extended in the extending direction of the horizontal holes 7, they do not cross each other in the core mold 3e. That is, if there is no connection hole 8 which is a drill hole processed in the B direction, the continuous flow path F of the cooling medium is not configured (see FIG. 2).

  In this embodiment, the connecting hole 8 is formed in the insert 21 inserted into the core mold 3e. A connecting hole 8 is formed by drilling in the B direction in the figure with respect to the insert 21, and further, a horizontal hole connected to the horizontal hole 7 is processed from the A direction and the C direction so as to intersect the connecting hole 8. The opening at the end of the connecting hole 8 is closed by inserting a cap 21C. Needless to say, when processing the horizontal hole 7 and the connecting hole 8, the processing positions in the depth direction with reference to the mounting surface of the core mold 3e are matched.

  FIG. 4 is a perspective view schematically showing a core mold according to the present embodiment. Two horizontal holes 7 are machined between the eject pins 10 that are arranged vertically through the core mold 3e. The lateral hole 7 is processed so as to communicate from the opening 23 on the side surface of the core mold 3e to the opening 22 on the side surface of the insert receiving portion 25. The insert 21 is inserted into the insert receiving portion 25, and the opening 21 a of the insert 21 connected to the connecting hole 8 and the opening 22 of the lateral hole 7 are joined together, whereby the cooling medium flow path F (see FIG. 3) is communicated. The opening 23 located on the side surface of the core mold 3e is connected to a cooling flow path (not shown) of the mother mold 3d. A cooling medium is supplied to one side of the horizontal hole 7 from the cooling flow path of the mother die 3 d and is returned to the mother die 3 d from the other horizontal hole 7 via the flow path F. As a result, the cooling medium circulates in the movable mold 3 and the core mold 3e is cooled.

  FIG. 5 is a schematic view showing a DD cross section (see FIG. 3) of the core mold 3e. The upper surface in the figure is a mounting surface in contact with the receiving plate 3c, and the lower surface is a surface constituting the cavity C. The insert 21 is inserted into the insert receiving portion 25 (see FIG. 4) from the mounting surface side. A flange is provided on the upper surface of the insert 21 and is fixed to the core mold 3 e by a fixing screw 31. By inserting the insert 21, the opening 22 and the opening 21 a are joined, and the lateral hole 7 and the connecting hole 8 communicate with each other. An O-ring 32 for preventing leakage of the cooling medium is mounted on the joint surface between the opening 22 and the opening 21a.

  A draft angle 33 is provided on the side surface of the insert 21, and the opening on the top surface is wider than the bottom surface of the insert 21. Thereby, when inserting the insert 21 into the insert receiving portion 25 and when removing it, the O-ring 32 is rubbed between the side surface of the insert 21 and the side surface of the insert receiving portion, causing positional displacement and damage, The possibility of causing leakage of the cooling medium can be eliminated.

  FIGS. 6 and 7 are schematic views showing an aspect of the core mold 3e in which the mounting position of the insert 21 is shifted. In the present embodiment, the flow path of the cooling medium can be changed by changing the setting position of the insert 21 as shown in the figure. Thereby, the setting of the flow path according to the point to be cooled in the cavity C becomes possible.

  In the core mold 3e shown in FIG. 6, the set position of the insert 21 is moved to the left in the figure from the position shown in FIG. Thereby, the flow path of the cooling medium is changed from F to G in the figure. On the other hand, in the core mold 3e shown in FIG. 7, the set position of the insert 21 is moved to the right in the drawing from the set position shown in FIG. Thereby, the flow path of the cooling medium is changed from F to H in the figure.

  The flow path of the cooling medium shown in FIGS. 6 and 7 can be easily implemented only by changing the position where the insert is inserted and changing the depth of the lateral hole 7. That is, a suitable cooling point is selected according to the shape of the cavity C, and the setting position of the nest 21 can be easily designed so as to provide a cooling medium flow path with high cooling efficiency.

  In designing the molding die, it is necessary to change the position to be cooled in the cavity C in accordance with the shape of the molded product in which the thick part and the thin part of the resin are mixed. If the present invention is implemented as described above and the flow path of the cooling medium is accurately set for the point to be cooled, defects in the molded product can be eliminated, and further, the cooling time can be shortened to improve the production efficiency. Is possible.

  For example, a cooling medium flow path is set in the vicinity of a thick part that takes time to cool, and cooling is promoted so that the entire molded product is uniformly cooled, thereby shortening the cooling time. At the same time, distortion remaining in the molded product can be eliminated, and deformation after removal from the mold can be prevented. It is also possible to set a flow path for the cooling medium in the vicinity of the gate where the volume of the filled molten resin is large, thereby preventing surface defects such as shrinkage.

  FIG. 8 is a schematic view showing a molding die according to another embodiment of the present invention. From the side surface of the core mold 3e on which the eject pin 10 is arranged, holes to be a plurality of lateral holes 7 are drilled in the A direction and the C direction shown in the figure. These horizontal holes 7 are processed in parallel to the mounting surface of the core mold 3e, and as described above, are processed by shifting the position in the vertical direction in the figure, so that they do not cross each other in the core mold 3e. .

  A vertical hole 41 is formed at the end of each horizontal hole 7 in the core mold 3e so as to cross the horizontal hole 7 from the mounting surface side toward the cavity C side (see FIG. 9). That is, the vertical hole 41 communicates with the horizontal hole 7 inside the core mold 3e. The cooling holes 42 are independently formed from the mounting surface side toward the cavity C side. The vertical hole 41 and the cooling hole 41 are communicated with each other by a connection pipe 43, and the flow path of the cooling medium is configured by the horizontal hole 7, the vertical hole 41, the cooling hole 41, and the connection pipe 43.

  The cooling hole 42 is disposed at a position corresponding to the point to be cooled in the cavity C, and enables efficient cooling of the resin. In addition, when there are a plurality of points to be cooled, a plurality of cooling holes 42 corresponding to the number of the points should be formed at suitable positions and communicated by the connection pipe 43 to form a cooling medium flow path. At this time, the formation position of the cooling hole 42 is not limited by the ejector pin 10.

  FIG. 9 is a view schematically showing an EE cross section (see FIG. 8) of the core mold 3e. The vertical hole 41 and the cooling hole 42 are processed into a counterbore surface formed on the mounting surface of the core mold 3e. This is to prevent the pipe 43 from becoming an obstacle when the core mold 3e is attached to the receiving plate 3c. The vertical hole 41 intersects with the horizontal hole 7 and communicates with an opening 45 shown in one vertical hole 41 in the drawing. The same applies to the other vertical hole 41 where the opening 45 is not shown.

  Inside the cooling hole 42, there is provided a partition wall 42 that separates the internal space and forms a cooling medium introduction path and a discharge path. A connection pipe 43 is coupled to each of the separated introduction path and the discharge path, and the cooling medium supplied from one vertical hole 41 flows from the introduction path of the cooling hole 42 to the discharge path, and enters the other vertical hole 41. Discharged. Since the cooling medium circulates to the tip of the cooling hole 42 by the partition wall 42, the cooling point where the cooling hole 42 is disposed can be efficiently cooled.

  In the above embodiment, cooling can be efficiently performed by processing the cooling hole 42 at the point to be cooled in the cavity C. Further, the cooling hole 42 is relatively easy to form without being limited to the arrangement of the ejector pins 10. Further, the number of cooling holes 42 is not limited. Therefore, by applying the present embodiment, it is possible to realize a molding die having a cooling medium flow path having a high degree of freedom and efficiency.

  Although the preferred embodiments of the present invention have been described in detail above, the molding die according to the present invention is not limited to the above-described embodiments, and is within the scope of the gist of the present invention described in the claims. Various modifications and changes are possible.

It is a schematic diagram which shows the cross section of the shaping die based on this invention. It is the schematic diagram which showed the flow path of the cooling medium of the shaping die based on a prior art. It is the schematic diagram which showed the molding die concerning Example 1 of this invention. It is the perspective view which showed typically the shaping die based on Example 1 of this invention. It is the schematic diagram which showed DD cross section of the shaping die based on Example 1 of this invention. It is the schematic diagram which showed another aspect of the shaping die based on Example 1 of this invention. It is the schematic diagram which showed another aspect of the shaping die based on Example 1 of this invention. It is the schematic diagram which showed the molding die concerning Example 2 of this invention. It is the schematic diagram which showed the molding die concerning Example 2 of this invention.

Explanation of symbols

1 Mold 2 Fixed mold (female)
2a Fixed side mounting plate 2c Fixed side mold 3 Movable side mold (male)
3a Movable side mounting plate 3c Back plate 3d Movable side base 3e Core type 7 Horizontal hole 7
8 Connecting hole 10 Ejector pin 21 Nesting 25 Nesting receiving part 33 Draw angle 41 Vertical hole 42 Cooling hole 43 Connection pipe 46 Bulkhead
C cavity F, G, H Coolant flow path

Claims (4)

A molding die in which a male mold and a female mold are clamped to perform resin molding,
A plurality of lateral holes that are provided from the side of at least one of the male mold and the female mold toward the inside, and do not intersect within the mold; and
In order to connect the plurality of lateral holes to form a flow path for the cooling medium, a connecting portion processed on the mounting surface of the mold,
A molding die comprising: The connecting portion is
A nest for insertion into the mold;
A nesting receiving portion provided in communication with the plurality of lateral holes and receiving the nesting;
A connecting hole provided in the nest for connecting the plurality of lateral holes to form a flow path for the cooling medium;
The molding die according to claim 1, comprising: The nested receiving part is
3. The molding die according to claim 2, wherein a draft angle is set so that an opening for receiving the insertion is wider than a bottom surface. The connecting portion is
A plurality of vertical holes formed from the mounting surface of the mold toward a cavity where resin is molded, and intersecting each of the plurality of horizontal holes;
A cooling hole formed in the vicinity of the cooled portion of the cavity from the mounting surface of the mold toward the cavity, and having a partition that divides the cooling medium introduction path and the discharge path,
A plurality of connecting pipes communicating with the vertical holes and the cooling holes;
The molding die according to claim 1, comprising:

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