JP2016147407A - Metal mold device production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of a metal mold device comprising a temperature adjustment pipe, capable of suppressing deformation of the metal mold, improving and maintaining metal mold accuracy, and preventing strain or unevenness on a plated layer formed on a cavity side surface.SOLUTION: The production method of a metal mold device comprising a cavity between an upper metal mold 2a and a lower metal mold 2b formed so as to adjust temperature freely, comprises: a first step for depositing temperature adjustment pipes 3 for passing a fluid for temperature adjustment for adjusting temperature on the upper metal mold and lower metal mold, on a surface 22 opposite to the cavity, on the upper and lower metal molds; a step for coating with a coating member 4, the surface opposite to the cavity, on the upper and lower metal molds, so as not to expose the deposited temperature adjustment pipes 3 after the first step; a third step for performing plating processing to the cavity side face in a state of coating the surface opposite to the cavity with the coating member, on the upper and lower metal molds; and a fourth step for removing the coating member after the third step.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for manufacturing a mold apparatus.

  A mold apparatus used for resin molding usually has a structure having a cavity for enabling molding of a resin molded product having a predetermined shape and structure between an upper mold and a lower mold. ing.

  Conventionally, the mold apparatus has been devised and improved from various viewpoints. For example, there is a device for adjusting the heating temperature for controlling the inflow of the resin into the cavity and its curing. Further, there are contrivances regarding the surface treatment of the mold for improving the surface smoothness of the resin molded product, the deterioration of the mold surface in contact with the resin, and the prevention of damage.

  Specifically, it has been proposed to weld a temperature adjustment pipe for allowing a temperature adjustment fluid to pass through on the surface opposite to the cavity side of each of the upper mold and the lower mold (for example, (See Patent Document 1).

  Further, in recent years, in order to improve the durability of the cavity side surface and to finish the design surface of the resin molded product to a mirror surface, a plating layer is formed by plating the cavity side surface. ing.

  FIG. 5 shows a schematic cross-sectional process diagram of a conventional method of manufacturing a mold apparatus in which such improvements and improvements have been made. In this method, first, the steel material 1 which is the material of the mold 2 is shaved until the cavity-side surface 21 and the cavity-side surface 22 of the mold 2 have a predetermined design dimension. A final finishing process is performed to manufacture the mold 2 (step S3-1).

  Next, the mold 2 is immersed in the plating solution 51 of the plating bath 5 to perform plating, and the plating layer 6 is formed on the surface of the mold 2 (step S3-2). Next, the temperature adjustment pipe 3 for allowing the temperature adjustment fluid to pass through the surface 22 opposite to the cavity-side surface 21 is welded (step S3-3). And the mold member 7 etc. are attached to the metal mold | die 2, and a metal mold | die apparatus is completed (process S3-4).

JP-A-2-76709

  However, in the above-described conventional method, after the final finishing step (step S3-1) and the plating step (step S3-2) of the cavity-side surface 21, the temperature adjustment pipe is provided on the surface 22 opposite to the cavity. 3 welding process (process S3-3) is performed. Therefore, unexpected deformation may occur in the entire mold 2 due to high heat of welding. Then, due to unexpected deformation of the mold 2, there is a problem that the molded resin molded product does not have the dimensions and accuracy as designed.

  Moreover, since the welding step (step S3-3) of the temperature adjusting pipe 3 is performed after the plating treatment step (step S3-2), the plating layer 6 becomes locally high in temperature, and the plating layer 6 is distorted and uneven. As shown in FIG. 6, distortion 11 and unevenness 12 sometimes appeared on the design surface of the molded resin molded product 10.

  In order to suppress the deformation of the mold 2 and the distortion and unevenness of the plating layer 6, it is necessary to perform the welding operation in consideration of the heating temperature when welding the temperature adjusting pipe 3. However, since these welding operations are performed manually, it is very difficult to stably manufacture a high-quality mold apparatus.

  The present invention has been made in view of the above-described conventional problems, and in a mold apparatus provided with a temperature adjusting pipe, the deformation of the mold is suppressed, the mold accuracy is maintained and improved, and the cavity side surface is formed. It is an object of the present invention to provide a method of manufacturing a mold apparatus that prevents the plated layer from being distorted or uneven.

  The present invention is characterized by the following in order to solve the above problems.

  A method of manufacturing a mold apparatus having a cavity between an upper mold and a lower mold formed so as to be temperature-adjustable, the surface of the upper mold and the lower mold opposite to the cavity A first step of welding a temperature adjusting pipe for passing a temperature adjusting fluid for adjusting the temperature of the upper die and the lower die, and the temperature adjustment welded after the first step. Covering the surface opposite to the cavity in the upper mold and the lower mold with a covering member so as not to expose the piping for use, and the cavity in the upper mold and the lower mold Comprises a third step of plating the cavity side surface in a state where the opposite surface is covered with the covering member, and a fourth step of removing the covering member after the third step. And

  According to the present invention, in a mold apparatus including a temperature adjusting pipe, the deformation of the mold is suppressed, the mold accuracy is maintained and improved, and the plating layer formed on the cavity side surface is not distorted or uneven. A method for manufacturing a mold apparatus is provided.

It is a schematic sectional process drawing which shows one Embodiment (1st Embodiment) of the manufacturing method of the metal mold | die apparatus of this invention. (A) is a schematic sectional drawing of the upper metal mold | die equipped with the coating | coated member, (b) is a schematic sectional drawing of a lower metal mold | die. It is a partial expanded sectional view of the joined part of a metallic mold and a covering member. It is a schematic sectional process drawing which shows 2nd Embodiment of the manufacturing method of the metal mold | die apparatus of this invention. It is a schematic sectional process drawing which shows the manufacturing method of the conventional metal mold | die apparatus. It is the schematic which shows the state which distortion and the nonuniformity appeared on the design surface of the resin molded product.

  Hereinafter, modes for carrying out the invention will be described in more detail.

The mold apparatus manufacturing method manufactures a mold apparatus having a cavity between an upper mold and a lower mold formed so as to be adjustable in temperature. The method for manufacturing the mold apparatus includes at least the following first to fourth steps.
(1) 1st process: The process of welding the temperature adjustment piping which lets the fluid for temperature adjustment for adjusting the temperature of a metal mold | die pass to the surface on the opposite side to a cavity.
(2) 2nd process: The process of coat | covering the surface on the opposite side to a cavity with a coating | coated member so that the welded pipe for temperature control may not be exposed.
(3) Third step: A step of plating the surface on the cavity side with the surface opposite to the cavity covered with the covering member.
(4) Fourth step: A step of removing the covering member after the step of performing the plating treatment.

FIG. 1 shows a schematic cross-sectional process diagram of an embodiment (first embodiment) of a method for manufacturing a mold apparatus according to the present invention. Hereinafter, it demonstrates in detail along each process of FIG.
(Step S1-1: Preparation Step)
First, as in the prior art, a steel material 1 that is a material of a mold 2 to be used later as an upper mold 2a and a lower mold 2b is a cavity-side surface (hereinafter simply referred to as a mold surface) 21 of the mold 2; A predetermined design thickness is cut from a surface 22 (hereinafter simply referred to as a back surface) opposite to the cavity. Then, both the mold surface and the back surface 22 are processed to the final finish, and the mold 2 is manufactured. The material and thickness of the mold 2 are not particularly limited and can be appropriately determined in consideration of the shape and size according to the purpose and application of the mold 2. A tool steel such as carbon tool steel or the like, and a thickness of about 3 to 50 mm is considered.

In the present invention, the final finish of the mold is a mirror finish when the resin molded product is mirror finished, and when the texture is formed on the resin molded product, an unevenness corresponding to the texture is formed. Means processing.
(Process S1-2: 1st process)
Next, the temperature adjustment pipe 3 for allowing the temperature adjustment fluid to pass through the back surface 22 of the mold 2 is welded. The material, diameter, length, layout design, and the like of the temperature adjusting pipe 3 are not particularly limited as long as the mold 2 is uniformly heated to a predetermined set temperature, and can be determined as appropriate.

The method for welding the temperature adjusting pipe 3 is not particularly limited as long as the temperature adjusting pipe 3 is firmly fixed to the back surface 22 of the mold 2. For example, welding, brazing, soldering, etc. Can be applied.
(Step S1-3: Second step)
Next, the covering member 4 is mounted so as to cover the back surface 22 of the mold 2 so that the welded temperature adjusting pipe 3 is not exposed. FIG. 2 shows the cases of (a) the upper mold 2a and (b) the lower mold 2b.

The covering member 4 is mounted to prevent the plating solution 51 from adhering to the temperature adjusting pipe 3 in the next third step (step S1-4). The material of the covering member 4 is not particularly limited as long as it is not eroded by the plating solution 51. Examples of such a material include those in which a resin coating is formed on the surface of a resin molded product or a metal molded product.
(Step S1-4: Third step)
Next, the mold surface 21 of the mold 2 on which the covering member 4 is mounted is immersed in a plating solution 51 of the plating bath 5 to perform a plating process, and the plating layer 6 is formed on the mold surface 21. The type of the plating process is not particularly limited, and for example, a plating process such as chrome plating or nickel plating can be applied. Among these, hard chrome plating can be particularly suitably applied.

  When the temperature adjustment pipe 3 is made of copper and the plating solution 51 adheres to the temperature adjustment pipe 3, the attached portion may corrode depending on the type of the plating solution 51. Further, the flux used at the time of welding the temperature adjusting pipe 3 may float as foreign matter in the plating solution 51, and these may adhere to the mold surface 21 during the plating process and cause a pinhole or the like in the plating layer 6. . Therefore, in the plating process, it is important that the plating solution 51 is not attached to the temperature adjusting pipe 3.

  As a countermeasure, it is desirable to provide a waterproof mechanism at the joint between the edge of the mold 2 and the covering member 4. FIG. 3 shows a partially enlarged cross-sectional view of the joint portion between the mold 2 and the covering member 4.

In the joint portion shown in FIG. 3, a waterproof mechanism comprising a double packing 9 is provided along the edge of the cavity of the mold 2, and the joint is firmly joined by the bolts 8 to prevent the plating solution 51 from entering.
(Step S1-5: Fourth step)
When the third step is completed, the covering member 4 is removed from the mold 2.
(Process S1-6: 5th process)
Next, the mold apparatus is completed by attaching the mold member 7 or the like to the mold 2 from which the covering member 4 has been removed.

  By 1st process (process S1-2), 2nd process (process S1-3), 3rd process (process S1-4), 4th process (process S1-5), and 5th process (process S1-6) According to the method for manufacturing a mold apparatus, since the third step (step S1-4) is performed after the first step (step S1-2), heat is not locally applied to the formed plating layer 6. . For this reason, distortion, unevenness, etc. occurring in the plating layer 6 of the mold surface 21 can be suppressed. That is, it is possible to prevent defects due to the occurrence of distortion, unevenness, etc. generated on the design surface of a resin molded product molded by the manufactured mold apparatus.

In addition to the above-described embodiment, the mold device manufacturing method of the present invention is cut into a state in which a thickness is left more than the final finish of the mold surface 21 before the first step (step S1-2). After one step (step S1-2), the final finish of the mold surface 21 can be performed. FIG. 4 shows a schematic sectional process diagram of the embodiment (second embodiment) in this case. Hereinafter, the manufacturing method of the metal mold apparatus of 2nd Embodiment is demonstrated in detail along each process of FIG.
(Step S2-1: First Preliminary Step)
First, the mold surface 21 of the steel material 1 which is the material of the mold 2 is cut to the intermediate body 23 in a state where the thickness is left more than the final finish. The thickness remaining after the final finish is not particularly limited, but it is usually considered that the thickness is about 0.5 mm thicker than the final finish. On the other hand, the back surface 22 is cut into a final finish at this stage to produce the mold 2.
(Process S2-2: 1st process)
Next, as in the first embodiment, the temperature adjusting pipe 3 for allowing the temperature adjusting fluid to pass through the back surface 22 of the mold 2 is welded.
(Step S2-3: Second preliminary step)
Next, in the first preliminary step (step S2-1), the intermediate body 23 processed so as to have a thickness larger than that of the final finish is cut to the final finish of the mold surface 21. At this stage, all the surfaces of the mold 2 are in a state of being cut to the final finish.

  Thereafter, as in the first embodiment, a second step (step S2-4), a third step (step S2-5), a fourth step (step S2-6) are performed on the manufactured mold 2. A 5th process (process S2-7) is performed.

  According to the mold apparatus manufacturing method of the second embodiment described above, high dimensional accuracy is achieved by performing the second preliminary step (step S2-3) of the mold surface 21 after the first step (step S2-2). It becomes possible to set it as a metal mold apparatus. That is, even when distortion or unevenness occurs on the mold surface 21 of the mold 2 due to heat generated when the temperature adjusting pipe 3 is welded, the final finishing of the mold surface 21 causes the distortion or unevenness to be removed. A mold apparatus with high dimensional accuracy can be obtained.

  Further, after the first step (step S2-2), the second preliminary step (step S2-3) of the mold surface 21 is performed, and further, the third step (step S2-5) is performed on the mold surface 21. Therefore, no distortion or unevenness occurs in the plating layer 6 on the mold surface 21. That is, it is possible to prevent defects such as distortion and unevenness generated on the design surface of the molded resin molded product.

  As mentioned above, although the manufacturing method of the metal mold | die apparatus of this invention was demonstrated based on embodiment, the manufacturing method of the metal mold | die apparatus of this invention is not limited to said embodiment, In the range which does not deviate from the summary Various changes can be made.

  For example, in the first preliminary step (step S2-1), the mold surface 21 is cut to a state where the thickness is left more than the final finish, but only the mold surface 21 of the design surface is left thicker than the final finish. You may make it cut to a state. As a result, it is possible to prevent at least the distortion and unevenness of the design surface in the resin molded product.

2a Upper mold 2b Lower mold 21 Cavity side surface (mold surface)
22 Side opposite to the cavity (back side)
23 Intermediate with more thickness than the final finish 3 Temperature adjustment piping 4 Covering member

Claims (2)

A method of manufacturing a mold apparatus having a cavity between an upper mold and a lower mold formed so as to be adjustable in temperature,
In the upper mold and the lower mold, a temperature adjusting pipe for allowing a temperature adjusting fluid for adjusting the temperature of the upper mold and the lower mold to pass through on a surface opposite to the cavity. A first step of welding;
After the first step, in the upper die and the lower die, the surface opposite to the cavity is covered with a covering member so that the welded temperature adjusting pipe is not exposed,
A third step in which, in the upper mold and the lower mold, the surface on the cavity side is plated with the surface opposite to the cavity covered with the coating member;
After the third step, a fourth step of removing the covering member is provided. Before the first step, in the upper die and the lower die, a first preliminary step of cutting the surface on the cavity side in a state leaving a thickness rather than the final finish, and after the first step, The method for manufacturing a mold apparatus according to claim 1, further comprising: a second preliminary step of final finishing the surface on the cavity side in the upper mold and the lower mold.

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