JPS62101344A - Forming method for casting mold for flat casting - Google Patents

Abstract

PURPOSE:To form a casting mold by a small quantity of sand to be used and a few kinds of metallic flasks, by placing as specified said metallic flask on a surface plate on which a model has been placed, when executing the molding by using the metallic flask provided with a lattice-shaped part, and the model. CONSTITUTION:A model 2 is placed on a surface plate 1, and a filler block 3 consisting of a shape is placed on its side. Also, a metallic flask 4 is placed on the filler block 3 with its lattice-shaped part 5 down in the opposite way to its usual method for use. In this way, the lattice-shaped part 5 is set to a position separated by a small distance from a right above part of the model 2, namely, the upper face of the model 2. Subsequently, a gate stick 6 and a chiller, etc., are set to the model 2, and thereafter, a self-hardening sand is poured in from the upper direction, and a sedimentary layer 7 of the self- hardening sand is formed. When the layer 7 has been hardened, the flask 4 is suspended, the model 2 is drawn out, and a casting mold 8 for an upper mold which has been formed as one body with the flask 4 is obtained. In the same way, a casting mold for a lower mold 9 which has been molded is inverted and placed on the molding board 1, the casting mold 8 is aligned on it and a molten metal is poured, and a flat casting is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for manufacturing a flat casting mold.

(Prior art) Generally, when casting flat castings whose planar shape is sufficiently large compared to the height, conventionally, as shown in Fig. 4, a normal deep metal frame 4.4 and a model with a low height are used. A flat casting cavity 20 is formed, and casting is performed using molds 22 and 23 in which sand 21 is filled in the metal frame other than the cavity. (Note 5 is a lattice-like part for strengthening the back of the sand grain layer.

(Problems to be Solved by the Invention) Therefore, according to the conventional molding method described above, the amount of sand used per unit weight of the casting is extremely large and unreliable, the molding time is long, and the mold is large. There were problems such as it was difficult to remove the plate. Therefore, it may be possible to prepare and use a variety of shallow metal frames with flat areas that correspond to the shape of each flat casting, but in this case, the production cost would increase because a metal frame with multiple rods would be prepared, and the metal frame would be too small. Management becomes complicated and the storage space for gold frames becomes large.

This invention solves the above-mentioned conventional problems, and aims to provide a mold making method for flat castings that uses less sand and fewer types of metal frames.

(Means for Solving the Problems) However, in the method of making a mold for flat casting according to the present invention, a model is placed on a surface plate, and a metal frame provided with a lattice-like part is placed directly in the shape of the above-mentioned model. Place the self-hardening sand on the surface plate with a spacer in between, and pour self-hardening sand onto the model to form a deposited layer of self-hardening sand that reaches above the lattice-shaped part, and This is a mold manufacturing method for flat castings, characterized in that the model is removed after the layer has hardened.

(Function) In the mold making method of the present invention, the self-hardening sand that covers the upper surface J3 and side surfaces of the model is poured until it reaches above the lattice part of the mold, hardens, and becomes integrally fixed to the lattice part. A mold is obtained. By selecting the height of the spacing material, the lattice part of the metal frame can be set close to the top of the model, and once the self-hardening sand is piled up above this lattice part for a predetermined amount of Jft, it is filled deeper into the metal frame. It is not necessary to fill the entire frame with self-hardening sand, and the planar projection shape of the deposited layer of self-hardening sand may deviate from the shape that surrounds the outer peripheral side of the model with a thickness sufficient to withstand the pressure of the molten metal. Since it is not necessary, only a small amount of self-hardening sand can be used, and the weight of the vJ type can also be reduced. Furthermore, by changing the height of the spacer, it is possible to create many types of flat casting molds using a small number of metal frames.

(Example) An example of the present invention will be described below with reference to FIGS. 1 and 2.

First, a model 2 is placed on a surface plate 1, and a spacing member 3 made of section steel is placed on the side thereof. Then, the metal frame 4 is placed on the spacing member 3 with the lattice-like portion 5 facing downward, contrary to the usual usage. As a result, the grid portion 5 is set directly above the model 2, that is, at a position separated from the top surface of the model 2 by a short distance. Although four spacers 3 may be used to support the four sides of the metal frame 4, two pieces may be used to support the two opposing sides.

Next, the sprue rod 6 and a chiller (not shown) are set in the model 2, and then self-hardening sand is poured from above to the lattice part 5.
A deposited layer 7 of self-hardening sand is formed reaching above. After leaving it for a predetermined time and the layer 7 is hardened, the metal frame 4 is
IJ-L is removed and the model 2 is handled to obtain a mold 8 for the upper mold integral with the metal frame 4. A lower mold 9 produced in the same manner is inverted and placed on a fixed a31 as shown in FIG. 2, and the mold 8 is placed on top of the lower mold 9, and melt is poured thereon to produce a flat casting. Note that the same parts in the figure as in FIG. 1 are given the same reference numerals as in FIG. 1.

In this way, the amount of sand used is greatly reduced compared to the conventional method shown in FIG. 4, since it is only necessary to cover the model 2 and the grid portion 5.

FIG. 3 shows another embodiment of the present invention, in which instead of the deep metal frame 4 conventionally used for molding, a lattice-like part 5 (4) is used.
A special shallow metal frame 11 with a support rod 10 fixed to M is used, and this metal frame 11 is supported by a spacer 12 made of a square rod made of styrene or wood. 196 molds 13 are placed close to the periphery and filled with self-hardening sand up to the inner surface of the spacer 12 so that the four circumferential surfaces of the deposited layer 7 are flat. In addition to the effects of the embodiment shown in FIG.
Casting τ (13) has the advantage that the weight is reduced by the weight of the metal frame 11.

The present invention is not limited to the above-mentioned embodiments; for example, the shapes of the frame and the spacer can be made into other shapes.

(Effects of the Invention) As explained above, according to the present invention, by simply combining a metal frame with a lattice-like part and a spacing material, the amount of sand used during mold making for flat castings can be reduced. The weight of the mold can be significantly reduced, and the number of types of metal frames can be reduced.

[Brief explanation of drawings]

Fig. 1 is a sectional view explaining the manufacturing process of type vI showing one embodiment of the present invention, Fig. 2 is a vertical sectional view of the mold, and Fig. 3 is equivalent to Fig. 1 showing another embodiment of the invention. FIG. 4 is a longitudinal sectional view of an example of a conventional mold. 1... Surface plate, 2... Model, 3... Spacing material, 4...
・Gold frame, 5... Lattice part, 7... Sedimentary layer, 8...
Mold, 9... Mold, 11... Metal frame, 12... Spacing material, 13... Mold.

Claims (1)

[Claims] Place the model on a surface plate, place a metal frame with a lattice-like part on the surface plate through a spacer with the lattice-like part positioned directly above the model, A method for making a mold for a flat casting, characterized by pouring self-hardening sand into the lattice part to form a deposited layer of self-hardening sand reaching above the lattice-shaped part, and removing the model after the deposited layer has hardened.