JP2553124B2 - Mold manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a mold manufacturing method for manufacturing a mold for Perth processing or the like by full-mold casting, and particularly to a metal mold used for full-mold casting. It is related to the production of a model die.

(Prior Art) Conventionally, as one of the manufacturing methods for manufacturing a mold used for press working, casting, etc., a model of a mold to be manufactured is formed of expanded polystyrene material and the model is placed in a mold sand. It is necessary to bury it in a mold and inject the molten metal into it, and to burn away the model embedded in the mold sand due to the heat of the molten metal, and to fill the cavity formed in the mold sand according to the outer shape of the model with the molten metal. A full-mold casting method is known in which a die is obtained.

On the other hand, as a method of producing a mold model used for such full-mold casting, automation and accuracy improvement have recently been attempted by introducing a computer or the like. One of the methods is to form three-dimensional shape data of a die by a computer and form a die model by an NC processing machine based on the data.

As another method, as disclosed in, for example, Japanese Patent Publication No. 61-47620, a die for a computer is used.
The die is further sliced from the dimensional shape data at evenly spaced pitches to obtain contour data for each slice, and based on this contour data, a plurality of thin plate-shaped panels having a thickness equal to the above pitch are provided in each slice portion. A mold model is obtained by processing the corresponding contour shape using a cutter or the like, and superposing and laminating the thin plate-shaped panels processed into the contour shape of each slice portion.

(Problems to be solved by the invention) However, in the former (that is, the method by NC processing) of the above-mentioned mold model manufacturing methods, cutting is performed from a rectangular parallelepiped material larger than the mold model to be manufactured. Therefore, there is a problem that a large amount of cutting is required, a long time is required, and cost is increased.

On the other hand, in the case of the latter (that is, the method of polymerizing thin plate-shaped panels), since the shape part surface of the mold model corresponding to the mold surface of the mold is a curved surface, the pitch in slicing the mold needs to be considerably small. There is. Therefore, it is necessary to use a large computer having a large calculation capacity and a large storage capacity as a computer, which increases the equipment cost. Further, there is a problem that a large number of thin plate-shaped panels must be processed into contour shapes corresponding to the respective sliced parts, which requires a long time.

The present invention has been made in view of the above points, and an object thereof is to appropriately use the above-mentioned method by NC processing and a method by polymerization of a thin plate-like panel in accordance with the shape of a mold model. This makes it possible to efficiently create a mold model.

(Means for Solving Problems) In order to achieve the above object, a solution means of the present invention is a manufacturing method for manufacturing a mold by full-mold casting using a mold model, wherein the shape of the mold model is The part is shaped by NC processing, and the support part of the mold model is formed by stacking a plurality of thin plate-shaped panels on each other.

(Operation) With the above configuration, in the present invention, in the mold model, the shape portion having a curved surface corresponding to the mold surface of the mold is accurately machined by the NC machining. Done. Moreover, the NC machining is limited to the shape part of the mold model, and since the machining material is a relatively small rectangular parallelepiped shape corresponding to the shape part, the cutting amount is small and the machining time is reduced. It can be shortened.

On the other hand, the supporting portion of the mold model is formed by superimposing a plurality of thin plate-shaped panels, but since this supporting portion does not have a curved surface over the whole like a shape portion, the thickness of the thin plate-shaped panel is Can be relatively thick. Therefore, when the computer slices the die into a plurality of cross-sectional portions from the three-dimensional shape data of the die at a pitch corresponding to the thickness of the thin plate panel to obtain the contour data of each sliced portion, the calculation is relatively easy. Therefore, the calculation capacity and storage capacity of the computer can be reduced. Further, the processing of the thin plate-shaped panel based on the contour data can be performed in a short time because the number of panels is small.

(Example) Hereinafter, the Example of this invention is described based on drawing.

FIG. 1 shows an overall process of a manufacturing method for manufacturing a mold by full-mold casting using a mold model according to an embodiment of the present invention. As shown in FIG.
When manufacturing a mold, first, in a computer, two-dimensional graphic data representing a plurality of types of decomposed plane images and appearance plane images of the mold to be manufactured are input, and the entire mold is input from the input data. Three-dimensional shape data representing an image is created and stored (S1).

Next, based on the data of the portion having the die surface of the die among the above three-dimensional shape data, the NC processing machine shapes the shape portion of the die model corresponding to the portion of the die (S
2). As shown in FIG. 2, this shaping process is performed by moving the cutting blade 2 of the NC processing machine in a zigzag pattern while vertically displacing the upper surface of the rectangular styrofoam material 1. Done.

At this time, the rectangular parallelepiped material 1 need only have a size corresponding to the shape part 3 of the mold model to be shaped, and the size is necessary when forming the entire mold model by NC processing. Since the material is much smaller than in the case of a rectangular parallelepiped material, the amount of cutting by the NC chemical machine is relatively small. This reduction in the cutting amount is not simply due to the fact that the shape taking is limited to a part of the mold model, and the shape taking part has a small volume ratio with respect to the supporting portion 5 (see FIG. 2) of the mold model. An important point is that the shape portion 3 is specified. That is, since the support portion 5 is wider than the shape portion 3 in a plane, when the shape of the mold model is taken,
This is because, in the case of a rectangular parallelepiped material that spreads in a plane corresponding to the support portion 5, the amount of cutting in the shaped portion 3 becomes very large. And since the cutting amount is reduced in this way, NC
The processing time due to the processing can be shortened, and the manufacturing cost can be reduced. Further, the curved surface processing of the shape portion 3 can be performed with high accuracy by NC processing.

On the other hand, a support for the mold model is formed in parallel with the shaping of the shape part 3 of the mold model (S3, S4, S5). In forming the supporting portion, first, in a computer that stores three-dimensional shape data of a mold, a lower side portion (mold model) of the three-dimensional shape data having a mold surface of the mold. (The portion corresponding to the supporting portion of 1), the lower portion of the mold is sliced in the longitudinal direction at a predetermined pitch to create contour data of each slice portion (S3). Then, based on the contour data, a plurality of styrofoam thin plate-shaped panels 4, 4, ... (See FIG. 3) are processed into contour shapes corresponding to the respective slice portions.

As the contour shape processing of each thin plate-shaped panel 4, for example, the contour shape of each slice portion is drawn on the recording paper by a printer device which is an output unit of the computer based on the contour data of each slice portion obtained by the computer. Then, a template for each slice portion is created from this recording paper, and the thin plate-shaped panels 4, 4, ... Are each cut into a predetermined contour shape by a cutter and processed using the template. In addition to this processing method, the thin plate-shaped panels 4, 4, ... can be directly cut out into a predetermined contour shape from the contour data of each slice portion obtained by a computer without using a template by an NC processing machine or the like. Is also good.

Then, the plurality of thin plate-shaped panels 4, 4, ... Processed into a predetermined contour shape by the method as described above are aligned with each other, and then adhered with an adhesive to be polymerized, thereby
The supporting portion 5 of the mold model as shown in the figure is formed (S5).
The support part 5 of the mold model has a mounting table part 5a for supporting the shape part 3 of the mold model in the center thereof, and rib parts 5b, ... Are arranged around the mounting table part 5a. .

As described above, in the case of the method of forming the supporting portion 5 of the mold model by superposing a plurality of thin plate-shaped panels 4, 4, ...
Since the whole is not formed into a curved surface like the shape part 3, the thickness of the thin plate-shaped panel can be set relatively thick. Therefore, when the computer slices the die into a plurality of cross-sectional portions at a pitch corresponding to the thickness of the thin plate panel from the three-dimensional shape data of the die to obtain the contour data of each sliced portion, the calculation is comparatively performed. Since it becomes easy and the computer has a small computing capacity and a small memory capacity, the computer to be used can be small in size, and the facility cost can be reduced. Further, the processing of the thin plate-shaped panels 4, 4, ... Based on the contour data can be performed in a short time because the number of panels is small.

Subsequently, as shown in FIG. 4, the shape part 3 is aligned and bonded by an adhesive on the mounting table part 5a of the support part 5 of the mold model formed by the respective different methods as described above. Thus, the mold model 6 is formed (S6). Then, after shaping the die model 6 with sandpaper or the like, a die is cast by the full molding method casting using the shaped die model 6 (S7). In this full molding method casting, as is known, the mold model is buried in the mold sand, then the molten metal is injected into the mold sand, and the heat of the molten metal burns out the mold model buried in the mold sand. At the same time, the molten metal is filled in the cavity formed according to the outer shape of the mold model in the mold sand to obtain a mold having a shape corresponding to the mold model. With the above, the manufacturing of the mold is completed.

(Effects of the Invention) As described above, according to the mold manufacturing method of the present invention, when the mold model is manufactured, the shape portion of the mold model having the curved surface corresponding to the mold surface of the mold is NC processed. Formed by superimposing a plurality of thin plate-shaped panels without a curved surface, it is possible to reduce the amount of cutting by NC processing, it is possible to reduce the number of thin plate-shaped panels, It is possible to shorten the manufacturing time of the die model, and also contribute to the improvement of the accuracy of curved surface processing and the reduction of the equipment cost.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a process diagram showing a method for manufacturing a mold, FIG. 2 is a perspective view showing a method for manufacturing a shape part of a mold model, and FIG. 3 is a mold. Perspective view of the model support,
FIG. 4 is a perspective view showing a mounting state of the shaped portion with respect to the support portion of the mold model. 3 ... Mold model shape part, 4 ... Thin plate panel, 5 ...
Support for mold models.

Claims (1)

(57) [Claims] 1. A manufacturing method for manufacturing a mold by full-mold casting using a mold model, wherein the shape part of the mold model is shaped by NC machining, and the supporting part of the mold model is formed. A method for manufacturing a mold, comprising forming a plurality of thin plate-shaped panels by superposing them on each other.