JPH04100655A - Mold molding device - Google Patents

Abstract

PURPOSE:To form a mold having high hardness and to improve the quality of a casting product by placing a flask on a lower molding board so as to surround a pattern and a raising flask divided into plural flask bodies on this flask and making the flask openable/closable at sand ramming and sand charging positions. CONSTITUTION:The flask 4 is placed on the lower molding board 3, and a table 2 is ascended with a squeeze cylinder 1, and the flask 4 is joined to the lower side of the raising flask 5. Successively, molding sand is charged into the raising flask 5 and the flask 4 from a sand hopper 6, and by shifting a frame 16, an upper molding board 9 is positioned on the lower molding board 3. Then, at the time of shifting the frame 16, the molding sand packed out from the upper face of raising flask 5 is scraped by a sand scraper 8 and leveled. Successively, by working a cylinder 11 for opening/closing in shortening direction, respective supporting bars 22, 23 are shifted in parallel in the facing direction and each flask body 5a of the raising flask 5 is closed at the molding hardening position. By this method, the outer peripheral part of the molding sand 18 is squeezed to increase the hardness.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a mold making device.

[Prior Art] A mold is usually formed by placing a casting flask on a lower surface plate having a model, pouring sand into the flask, and compressing the sand with the upper and lower surface plates. There is. In this case, if the casting sand is simply compressed using the upper and lower surface plates, the hardness of the outer peripheral portion of the formed mold may be insufficient, and the mold may become deformed.

To deal with this problem, it has been conventionally possible to increase the hardness of the casting sand by protruding a pressing piece from the outer periphery of the casting sand pressing surface of the upper surface plate and pressing the casting sand outer periphery in the vertical direction with the pressing piece. It has been proposed (for example, Utility Model Application Publication No. 54-134728
(see publication).

[Problems to be Solved by the Invention] According to the publication, a recess is formed on the pressing surface of the casting sand by the pressing piece of the upper surface plate.

For this reason, the lower mold in particular serves as the pressing surface of the casting sand or the installation surface with respect to the casting surface plate, so that the installation area of the installation surface is reduced.

As a result, the installation of the mold becomes unstable, and after the upper mold is assembled, the mold is likely to be deformed due to the load, molten metal casting pressure, external impact, the passage of time, etc., and there is a risk that the quality of the cast product will deteriorate.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a mold making device that can increase the hardness of the outer peripheral part of the mold and make the hardness of the mold uniform without forming a recess on the pressing surface of the casting sand.

[Means for Solving the Problems] A mold making apparatus of the present invention that solves the above problems comprises: a lower surface plate having a model on its upper surface; a casting flask placed on the lower surface plate so as to surround the model; A joint frame placed on the frame, an upper surface plate that presses casting sand with a lower surface plate, and the joint frame is further divided into a plurality of frame bodies,
The frame body is provided so as to be openable and closable between the casting position and the sand charging position.

[Operation] According to the above means, the frame body of the splicing frame is placed on the flask placed on the surface plate in an open state at the sand injection position, and casting sand is poured into the flask and the splicing frame. and then the casting sand is compressed in the central direction by closing the frame in a solidification position,
The casting sand is pressed vertically by the upper and lower surface plates.

1 example: Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a front half-sectional view of the mold making apparatus, and FIG. 2 shows a plan view thereof.

In FIGS. 1 and 2, squirrel cylinders 1 are installed in a striped manner on the heath IA. The squirrel cylinder 1 has a tiple 2 that is raised and lowered by the telescopic operation of the rod. A lower surface plate 3 having a model 7 on the upper surface is provided on the table 2.

A rectangular casting flask 4 surrounding the model 7 is placed on the lower surface plate 3. A half-sectional front view of the flask 4 is shown in FIG. 3, and a plan view thereof is shown in FIG. Therefore, the upper and lower end surfaces of the casting flask 4 are provided with kite surfaces 4 having an inclination of a predetermined angle.
A is formed.

In FIGS. 1 and 2, a frame 16 is disposed above the lower surface plate 3 and is movable in the horizontal direction via appropriate moving means (not shown). The frame 16 is provided with a rectangular box-shaped upper surface plate 9 for pressing the upper surface of the casting sand, and a sand hopper 6 for charging casting sand into the flask 4. The upper surface plate 9 and the sand hopper 6 are selectively positioned directly above the lower surface plate 3 by the moving means. Furthermore, frame 16
In this case, the shaft 8 is moved between the sand scraper 8 or the upper surface plate 9 and the sand hopper 6.
It is rotatably suspended via a. The upper surface plate 9 has a flat lower surface and a rectangular pressing surface 9a that substantially corresponds to the upper opening of the flask 4 (see the two-dot chain line in FIG. 4).

A joint frame 5 is arranged between the casting flask 4 and the upper surface plate 9. This joint frame 5 is constituted by four frame bodies 5a divided into four parts in the front, back, left and right in a plane.

The frame body 5a is shown in FIG. 5, which is a plan sectional view thereof, and VI in FIG.
As shown in FIG. 6, which is a cross-sectional view taken along the -Vl line, the through holes 51 and 52 have an abbreviated shape and pass through each side of the abbreviated shape.
or is formed. Further, a guide surface 53 having a slope of a predetermined angle is formed on the lower end surface. This kite surface 53 corresponds to the upper guide surface 4a of the casting flask 4 (see FIG. 1).

The frame body 5a can be opened and closed between a casting position and a sand charging position by an opening/closing device JO, which will be described below.

In FIGS. 1 and 2, a total of four pillars 15 on the front, rear, left and right sides are arranged vertically around the lower surface plate 3 via appropriate frame materials (not shown).

A slider 14 is fitted into each support column j5 so as to be movable up and down. The lowering position of the slider 14 is limited by a stopper 13 attached to each support column 15. A guide bar 20 is installed horizontally on each slider 14 so as to form a rectangular frame. Front and rear support bars 22 are installed on the left and right guide bars 20 so as to be slidable in the front and rear directions, respectively. To this support bar 22,
A through hole 51 in the left and right direction of each frame 5a is slidably penetrated therethrough. The support bar 22 has opening holes 22a formed in a symmetrical manner. Furthermore, left and right support bars 23 are installed on the front and rear kite bars 20 so as to be slidable in the left and right directions, respectively.

The left and right support bars 23 are slidably inserted into the through holes 52 in the front and rear directions of the frame 5a and slidably in the left and right directions through opening holes 22a opened in the front and rear support bars 22 (fifth, (See Figure 6).

At the center of the guide bar 20, opening/closing cylinders 11 such as air cylinders or their lots 11a are attached via brackets 25 so as to be oriented in opposite directions. lot ll
a are respectively attached to the support bars 22 of the tip blades via stays 26.

Therefore, when the frame 5a is in the sand input position as shown by the solid line in FIG. 2, the opening/closing cylinder 11
When the frame body 5a is shortened, each of the support bars 22, 23 is moved in parallel in opposite directions, and the frame body 5a
is closed toward the center to reach the solidification position shown by the two-dot chain line in FIG. The shape within the frame of the frame body 5a at the solidification position is approximately the same as the shape within the flask 4. In addition, in this state, the opening/closing cylinder 1
1, when the support bars 22 and 23 are moved in parallel in opposite directions, the frame body 5
a is opened radially to serve as the sand input position.

A case in which a mold is manufactured using the mold making apparatus will be described.

In addition, when charging sand, the joint frame 5 is placed in the sand charging position by the extension operation of the opening/closing cylinder 11.

Also, although not shown, the lower surface plate 3 is placed at a lower position than in FIG.

In this state, after the casting flask 4 is placed on the lower surface plate 3, the table 2 is raised by the squeeze cylinder 1,
A flask 4 is joined to the lower side of the joint frame 5. After that, casting sand is thrown into the joint frame 5 and the casting flask 4 from the sand hopper 6,
Next, the frame 16 is moved and the upper surface plate 9 is placed on the lower surface plate 3.
or located.

This state is shown by the solid line in FIG.

Further, the left half of FIG. 7 shows a sectional view of the state in which casting sand (denoted by reference numeral 18) is being poured. Incidentally, when the frame 16 is moved, the casting sand protruding from the upper surface of the joint frame 5 is cut and leveled by the sand scraper 8.

Next, by shortening the opening/closing cylinder 11, each of the support bars 22, 23 is moved in parallel in the opposite direction, thereby closing each frame 5a of the joint frame 5 to the solidification position (the first (See the dashed dotted line in Figure 2, and the dashed dotted line in the left half of Figure 7). This compresses the outer periphery of the casting sand 18 and increases its hardness.

Further, during the compression, the guide surface 53 of the frame 5a slides on the guide surface 4a of the flask 4, so that the frame 5a is closed while rising. Therefore, sand spillage due to the swelling of the casting sand 18 due to the compression is suppressed. Note that as the frame body 5a rises, the guide bar 20 and slider 14 are raised via the support bars 22, 23.

Thereafter, the table 2 is raised by the squeeze cylinder 1, and the casting sand 18 is vertically pressed by the lower surface plate 3 and the upper surface plate 9. In this way, the casting sand 18 is compressed to a substantially uniform hardness.

This state is shown in a sectional view in the right half of FIG.

Thereafter, the squeeze cylinder 1 lowers the table 2, and at the same time, the opening/closing cylinder 11 is extended to expand the frame 5a to the sand loading position, and the squeeze cylinder 1 lowers the table 2 and raises it. The casting sand 18 is released from the surface plate 9, and the casting flask 4 is released from the joint frame 5. Then, when the flask 4 is taken out from the lower surface plate 3, the eighth
A mold as shown in cross-section in the figure is obtained.

According to the mold making apparatus described above, the frame body 5a of the joint frame 5 is closed to the casting position by the opening/closing cylinder 11, and the casting sand 18 is closed.
Since the casting sand 18 is compressed toward the center, the hardness (density) of the outer periphery of the mold can be increased without forming a recess on the pressing surface of the casting sand 18, unlike the conventional method. Therefore, deformation of the mold can be prevented, and the quality of the cast product can be improved.

Note that the present invention is not limited to the above-mentioned embodiments, and modifications can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the present invention, by closing the frame body of the joint frame from the slotted position to the casting position, the casting sand is compressed toward the center and the hardness of the outer periphery of the casting sand is increased. Unlike the conventional method, a mold with high hardness can be obtained without forming a recess on the pressing surface. Therefore, deformation of the mold can be prevented, and the quality of the cast product can be improved.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a front half-sectional view of a mold making device, FIG. 2 is a plan view thereof, FIG. 3 is a front half-sectional view of a casting flask, and FIG. Its plan view, Fig. 5 is a plan sectional view of one frame, Fig. 6 is a sectional view taken along the line VI-VI in Fig. 5, and Fig. 7 is for explaining the operation of the mold making device. FIG. 8 is a cross-sectional view of the mold, showing the state immediately after casting sand is added, and the right half showing the state after pressing the sand. 3... Lower surface plate 4... Casting flask 5... Joint frame 5a... Frame body 9... Upper surface plate

Claims (1)

[Claims] A lower surface plate having a model on the upper surface, a casting flask placed on the lower surface plate so as to surround the model, a joint frame placed on the casting flask, and a lower surface plate for casting. an upper surface plate for pressing sand; further, the joint frame is divided into a plurality of frame bodies,
A mold making device characterized in that the frame body is provided so as to be openable and closable at a casting position and a sand charging position.