JPS61163291A - Forming die made by electrocasting and its production - Google Patents

Abstract

PURPOSE:To produce easily a forming die having excellent heat exchange efficiency by splicing a liq. passage forming body and a communicating part forming body on the rear surface of a electrocast cavity, electrodepositing an outer shell layer thereon, and then removing the spliced bodies. CONSTITUTION:A metal such as nickel is deposited in specified thickness by electrocasting to form a cavity 1 consisting of a molding part 2 and a flange part 3. A thin-walled communicating part forming body 4 consisting of a splice member capable of being removed by a chemical or a physical means such as dissolution, vaporization, and combustion is spliced along the rear surface of the cavity, and a liq. passage forming body 6 consisting of the same member is spliced on the surface of the body 4. Then an outer shell layer 7 is formed on the outer surface of a splice member 5 thus formed by depositing a metal such as nickel in specified thickness by electrocasting. The splice member 5 is then removed, and a hollow liq. flow passage 8 for the flow of a refrigerant and hot oil and a flat communicating part 9 communicating with the passage 8 are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a mold manufactured by an electroforming process (1) having a liquid flow path for cooling or heating a cavity, and a method for manufacturing the same.

[Prior art]

For example, in a plastic mold with a cavity formed by electroforming, in order to shorten the molding cycle, a copper or stainless steel pipe, for example, is closely placed along the back side of the cavity, and this pipe is soldered to the cavity. The pipe is integrated with a pipe, and cooling water or hot oil for heating is passed through the pipe.

However, in the above configuration, the cavity.

The pipe and the solder that connects the two have different coefficients of thermal expansion, so if heating and cooling are repeated, the temperature difference will increase, causing the relative positions to shift, and as a result, the solder will peel off and the cavity and pipe will be separated. There is a problem of disengagement.

To solve this problem, for example,
As disclosed in the above publication, a fusible part is adhered to the back surface of the cavity, and an electroformed metal layer is deposited to a constant thickness on the back surface of the cavity and the outer surface of the fusible member by an electroforming process. After precipitation, the fusible material is dissolved and removed to form a hollow liquid flow path with a uniform coefficient of thermal expansion, and a liquid such as oil or water is circulated through the liquid flow path to form the cavity. Also considered are devices that heat or cool.

However, since the liquid flows in the liquid flow passage in a laminar flow state, the liquid flowing along the inner wall of the liquid flow passage sufficiently exchanges heat with the cavity, but the liquid flows from the inner wall of the liquid flow passage to the cavity. For example, the liquid flowing in the center of the liquid flow path at a distance does not sufficiently exchange heat with the cavity, and the efficiency of heat exchange between the liquid and the cavity is generally low, and as a result, it takes time to heat and cool the cavity, resulting in a long molding cycle. There's always a problem.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and its first purpose is to improve the heat exchange efficiency between the liquid flowing in the liquid flow path and the cavity, and to reduce the length of molded particles. A second object of the present invention is to provide a mold manufactured by casting, and a second object is to provide a manufacturing method that can easily manufacture such a mold.

[Summary of the invention]

According to the present invention, a liquid flow path is formed on the back side of a cavity, and a flat and hollow communication part is formed along the back side of the cavity to communicate the liquid flow paths with each other, so that liquid flowing through the liquid flow path is formed. The first feature is that it creates a turbulent flow to improve heat exchange efficiency and shorten the molding cycle.
Vaporization.

After sequentially attaching a communication part forming body and a liquid flow passage forming body consisting of attached members that can be removed by chemical or physical means such as combustion, metal is deposited on the outer surface of these by electroforming. A shell layer is formed, and after the formation of the outer shell layer, attached members are removed by chemical or physical means to form liquid flow passages and communication parts, thereby making it easy to manufacture. It has a second feature.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

Reference numeral 1 denotes a cavity formed by depositing nickel to a predetermined thickness on the surface of a master (not shown), and a flange 3 oriented outward is integrally formed at the opening edge of the molded part 2 by nickel electroforming. has been done. Reference numeral 4 denotes a communication part forming body that is thinly attached along the back side of the cavity 1 after the formation of the cavity 1 so as to correspond to the molded part 2, and this is made of the nickel resin that formed the cavity 1.
! Low melting point alloy solder, paraffin, wax.

It consists of an attached member 5 made of resin or the like, and is attached to the back side of the cavity 1 by brazing or other means. Reference numeral 6 denotes a liquid flow passage forming body which is attached in a meandering manner to the outer surface of the communicating part forming body 4 after the communicating part forming body 4 is attached, and this is the same attached member 5 as the communicating part forming body 4. Consisting of When the communication part forming body 4 and the liquid flow passage forming body 6 are attached to the back side of the cavity 1 in this way (see Fig. 4), the cavity 1 is electroformed again, and the communication part Nickel is deposited to a predetermined thickness on the outer surfaces of the forming body 4 and the liquid flow passage forming body 6 to form an outer shell layer 7 (see FIG. 5). When forming the outer shell layer 7, if the attached member 5 is made of a non-conductive material such as paraffin, the outer surface should be coated with conductive paint or subjected to a well-known conductive process such as chemical plating before electroforming. be applied. Further, the thickness of the outer shell layer 7 is set to a size similar to that of the cavity 1. Then, when the cavity 1 in which the outer shell layer 7 is formed in this way is uniformly heated to a temperature higher than the melting point of the attached member 5 in a heating furnace or the like, and the attached member 5 is melted and removed, a hollow is formed on the back side of the cavity 1. A meandering liquid flow path 8 and a flat, hollow communication portion 9 that communicates the liquid flow path 8 with each other are formed along the back side of the cavity 1 (see FIGS. 1 and 3). Then, the cavity 1 in which the liquid flow passage 8 and the communication portion 9 are formed is set in a mold (not shown), and the mold is filled with a heat insulating material, resin, etc. as necessary, and the mold is formed. The mold is constructed.

Now, when the mold configured as described above is attached to a molding machine to mold a molded object, hot oil is directed from one open end of the liquid flow passage 8 to the other open end. The cavity 1 is heated by flowing the sea urchin to the direction indicated by the arrow A in FIG. 2 (J). In this case, since the flat and hollow communication part 9 communicates the upstream and downstream parts of the meandering liquid flow passage 8 with each other, a portion of the hot oil is communicated from the upstream side of the liquid flow passage 8 where the pressure is high. The liquid flows to the lower pressure downstream side of the flow path 8 through the portion 9 as shown by arrow B in FIGS. 1 to 3, but since the communicating portion 9 is flat and narrow, The flow velocity of the hot oil passing through is faster than the flow velocity of the hot oil flowing through the liquid flow passage 8, and it flows into the downstream side of the liquid flow passage 8 with force. B) is the flow direction of hot oil flowing through the liquid flow path 8 (arrow A)
, the hot oil in the liquid flow passage 8 flows into the communication part 9 and becomes turbulent under the influence of the hot oil flowing out from the communication part 9 . A temperature difference may occur between the center of the liquid flow passage 8 and the inner wall, such as when the hot oil flowing in the center and the hot oil flowing in the inner circumferential wall are sufficiently stirred and mixed and flow in a laminar flow state. disappears.

Therefore, heat exchange between the liquid and the cavity 1 can be performed effectively, and the cavity 1 can be heated within a short time. and,
When the temperature of the cavity 1 is raised to a predetermined temperature, a resin material such as PVC (base resin or powder) is supplied into the cavity 1, and when a predetermined thickness of resin is welded to the inner surface of the cavity 1, the excess is removed from the cavity 1. of resin material is discharged. After this, cavity 1 is further heated and P
Curing temperature of VC, e.g. 180 to 240°C
Hold for 2-3 minutes.

Next, if all the hot oil in the liquid flow passage 7 is discharged and instead cooling oil is supplied from one open end of the liquid flow passage 7 and discharged from the other open end, the above-mentioned method can be achieved. Similarly, the cooling oil flowing in the liquid flow passage 8 becomes turbulent and flows into the cavity 1.
The heat is efficiently taken away by the cooling oil, so that the molded product inside the cavity 1 is rapidly cooled. After the molded product in the cavity 1 has been cooled to the mold release temperature, the molded product is removed from the mold, and the above-described operations are repeated to manufacture the molded product.

According to the above structure, the attached member 5 can have an arbitrary cross-sectional shape compared to a copper pipe, and can be attached to the cavity 1 in a manner that matches the shape even if the uneven shape is complex, and the liquid flow passage 8 can be attached to the conventional structure. It is not a line contact like the copper pipe of , but is in contact with the cavity 1 over a wide area, and the hot oil and cooling oil flowing through the liquid flow passage 8 are not affected by the hot oil and cooling oil flowing through the communication part 9. Since the flow is in a turbulent state, cavity 1
The heating and cooling time of the mold can be significantly shortened compared to a conventional mold in which the fluid flowing through the liquid flow path is a laminar flow, and the molding cycle can be shortened.

In the above embodiment, the outer shell layer 6 is formed by electroforming, but it may be manufactured by metal spraying or the like other than electroforming.

Furthermore, it goes without saying that the resin material molded by the above-described cavity 1 may be other than PVC.

〔Effect of the invention〕

As is clear from the above description, the present invention provides a mold manufactured by electroforming that can improve the heat exchange efficiency between the liquid flowing in the liquid flow path and the cavity, and shorten the molding cycle. A manufacturing method for easily manufacturing such a mold can be provided.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional view, FIG. 2 is a back view, and FIG. 3 is an enlarged sectional view of the main part.
FIGS. 4 and 5 are enlarged cross-sectional views of key locations showing the manufacturing process. In the drawings, 1 is a cavity, 4 is a communication part forming body, 5 is an attached member, 6 is a liquid flow passage forming body, 7 is an outer shell layer, 8 is a liquid flow passage, and 9 is a communication part. Applicant: Ikegami Kaken Kogyo Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] 1. A cavity formed by depositing metal to a predetermined thickness by electroforming, an outer shell layer formed along the back surface of the cavity, and a shell layer formed along the back surface of the cavity. a liquid flow passage formed in a hollow shape in the outer shell layer; and a flat liquid flow passage formed between the back surface of the cavity and the outer shell layer along the back surface of the cavity so as to communicate with each other. A mold manufactured by electroforming and having a hollow communication part. 2. A process of depositing metal to a predetermined thickness by electroforming to form a cavity, and an attached member that can be removed by chemical or physical means such as melting, vaporization, or combustion along the back surface of the cavity. a step of attaching a thin communication part forming body made of the above-mentioned communicating part forming body, a step of attaching a liquid flow passage forming body made of the attached member to a surface part of the communicating part forming body, and a step of attaching a liquid flow passage forming body made of the attached member, A step of electrodepositing metal to a predetermined thickness on the outer surface of the path forming body by electroforming to form an outer shell layer, and forming the communication portion forming body and the liquid flow path forming body after forming the outer shell layer. forming a hollow liquid flow path and a flat, hollow communication section that is continuous with the liquid flow path and along the back surface of the cavity by removing the attached member by chemical or physical means. A manufacturing method for molds manufactured by electroforming.