JPH04113140U - Casting flask - Google Patents

Abstract

(57) [Summary] [Purpose] Good mold tightness near the inner surface, and
To obtain a casting flask whose inner surface can be easily cleaned during demolding and whose maintenance cost is low. [Structure] A plate material 9 whose surface in contact with molding sand has a low coefficient of friction is removably attached to the entire inner surface 8a of the main body 8 to improve mold tightness and facilitate cleaning.
Also made it replaceable.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a flask used in manufacturing castings.

0002

[Conventional technology]

Conventionally, molds for manufacturing castings are made using a model surface plate on which a model 1 is arranged, as shown in Fig. 4. 2 on the table 6 of the molding machine, place the casting flask 3 on the model surface plate 2, and After pouring the molding sand 4 into the sand tank (not shown) provided above in the frame 3, the molding machine The molding sand 4 is compressed by the squeeze head 5 and the mold is clamped, and then the model 1 is pulled out. The upper and lower molds are made by cutting out the molds.

0003 Therefore, the mold 4a molded as described above has friction with the inner surface 3a of the flask 3. Since the mold 4a is held only by force, when lifting the mold 4a during mold removal, etc. There is a risk that part or all of the mold may fall off, which is called mold drop.

0004 For this reason, conventionally, as a means to prevent mold drop, the surface roughness of the inner surface 3a of the flask 3 has been The friction between the inner surface 3a of the flask 3 and the molding sand 4 is It was also used to increase power.

[0005]

[Problem that the idea aims to solve]

However, by increasing the surface roughness of the inner surface 3a of the flask 3, the frictional force between it and the molding sand 4 is reduced. If the value is increased, there is a problem that the mold tightening during molding becomes poor. In other words, the flask The center and periphery of the molding sand 4 are pressed together by the squeeze head 5. Although the flow between the flasks 3 and 3a is smooth and the mold clamping is relatively good, This is because the flow of the molding sand 4 becomes unsmooth due to the large friction coefficient of the inner surface 3a. be.

[0006] As a countermeasure against this, the squeeze head 5 is divided into a plurality of parts and placed near the inner surface 3a of the flask 3. Developed a multi-squeeze head molding machine that applies even greater pressure. (for example, see Utility Model Publication No. 18969/1983), and has not been used recently. However, when the friction coefficient of the inner surface 3a of the flask 3 is large, the effect is small and still remains. There is a problem that the mold tightening of the lever part is insufficient.

[0007] In addition, after the molten metal injected into the mold cavity solidifies, the so-called mold release occurs. The mold 4a in the flask 3 is removed by cleaning, but the surface roughness of the inner surface 3a of the flask 3 is large. If the coefficient of friction is large due to rust or rust on the inner surface 3a, the inner surface 3a may be made of cast metal. Sand 4 is attached. In such a case, do not apply vibration to the flask 3 or use a brush, etc. Although the cleaning work is carried out, since the foundry sand 4 contains a binder, condensation may occur on the inner surface 3a of the flask 3. It is often difficult to remove.

[0008] For this reason, if the molding work is performed again without cleaning the inner surface 3a sufficiently, the inner surface 3a will be damaged. The accumulation of molding sand 4 increases, and as a result, the coefficient of friction increases, making mold tightness even worse. There are problems in that it causes mold tension, a decrease in dimensional accuracy, etc.

[0009] This invention solves the above-mentioned conventional problems and improves mold clamping during molding. In addition, there is less molding sand adhering to the inner surface of the flask when the mold is disassembled, and cleaning work is also easier. The purpose is to provide a casting flask that can be easily cast.

0010

[Means to solve the problem]

In order to achieve the above object, the casting flask of the present invention has at least a surface that is in contact with molding sand. A plate material formed on a surface with a friction coefficient is removably attached to the entire inner circumference of the flask body. It is characterized by:

[0011]

[Effect]

The inner surface of the main body is made of a plate material with at least the casting sand side formed with a surface having a low coefficient of friction. Since it is installed, the flow resistance of molding sand on the inner surface of the flask during molding is reduced and the mold is tightened. can improve performance. In addition, the peelability of molding sand during mold disassembly is improved, making cleaning easier. This can prevent excess molding sand from adhering. Furthermore, the frictional resistance of the plate material increases with use. When this occurs, remove the flask and replace it with a new plate to achieve the above effect. Since the fruit can last for a long time, there is no need to replace the entire casting flask with a new one, and management costs are low. It is inexpensive.

0012 In addition, due to the reduction in the friction coefficient of the inner surface of the casting flask of the present invention, it is easier to lift the mold when removing the mold. Mold drop, in which part or all of the mold falls during molding, can be avoided when molding using the flask of the present invention. This does not occur because the mold tightening is improved throughout the mold, especially around the flask.

[0013]

【Example】

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3. Figure 1 is a sectional view of a flask showing an embodiment of the present invention, and Figure 2 is a sectional view of a flask showing an embodiment of the present invention. Figure 3 is a plan view of the main parts showing the strength of the mold when molding is performed using a conventional casting flask. FIG.

[0014] In FIG. 1, the casting flask 7 of the present invention has a cast iron body manufactured in the same manner as a conventional casting flask. The inner surface 8a of 8 is made of a 5 mm thick iron plate with electroless nickel plating on both sides ( The liner) 9 is attached using attachment means such as screws (not shown). The friction coefficient of the above electroless nickel plating is μ = 0.1 to 0.2, which is similar to that of ordinary plating. This is lower than the friction coefficient μ of 0.4 to 0.5 for a flask without. Of course it is lower than cast iron. Therefore, during molding, the molding sand has low flow resistance on the inner surface of the flask 7, and the mold tightens. was able to improve.

[0015] When demolding, the inner surface 9a of the flask 7, which is in contact with the molding sand, is extremely smooth. The sand was removed well and cleaning was extremely easy. In addition, even if molding sand sticks firmly to the inner surface 9a, it can be easily removed with a brush, etc. We were able to.

[0016] Due to use, the inner surface 9a may wear out and the coefficient of friction may increase, resulting in mold tightening and sand falling. If the problem worsens, the above effect can be restored by turning the board 9 over and attaching it. If both sides have deteriorated, replace it with a new board 9. The effect can be restored. Of course, only the inner surface 9a in contact with the foundry sand should be made a surface with a low friction coefficient, and replaced as appropriate. May be repeated. Since it is replaceable in this way, there is no need to replace the entire flask with a new one as in the past. stomach.

Next, using the flask 7 and the conventional flask 3 (both flask internal dimensions are 700 x 900 x 380H), a prismatic model 1 with a side of 100 mm and a height of 150 mm is made. Each model 1 was placed on a model surface plate 2 so that the distance between each model 1 and the distance from the inner surface 8a of the casting flask 7 was 55 mm, and molding was performed using molding sand with a moisture content of 3.5%. The mold strength (N/cm ² ) near the corner of the flask 7 was measured.

[0018] The results are shown in each region in FIGS. 2 and 3. As can be seen from Figure 2 The mold strength of the mold made using the flask 7 of the present invention is higher than that of the conventional flask 3 in each part. It is generally higher than that using molds, and there is sufficient mold tightness near the inner surface 9a of the flask 7. being done.

[0019]

[Effect of the idea]

As mentioned above, according to the present invention, the mold clamping during molding is good, and the mold Less sand adheres to the inner surface of the flask during drying, and cleaning work is also easy. I can do that. Furthermore, if the above effects deteriorate, simply replacing the installed plate material will completely remove the entire casting flask. There is no need to renew the body, and the cost required for manufacturing and maintenance of casting flasks can be significantly reduced. It is something that

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a plan view of essential parts showing mold strength when molding is performed using the flask of the present invention.

FIG. 3 is a plan view of essential parts showing mold strength when molding is performed using a conventional flask.

FIG. 4 is a sectional view showing an example of a conventional molding method.

[Explanation of symbols]

1 model 2 Model surface plate 3 Casting flask 3a Inner surface 4 Foundry sand 7 Casting flask 8 Casting flask body 8a Inner surface 9 Board material 9a Inner surface

──────────────────────────────────────────────── ─── Continuation of front page (72) Creator Shigeru Uchida Hitachi Metals Co., Ltd. 5200 Mikajiri, Kumagaya City, Saitama Prefecture Inside Shikisha Equipment Development Research Institute

Claims (1)

[Scope of utility model registration request] 1. A casting flask, characterized in that a plate material in which at least the surface in contact with foundry sand is formed to have a low coefficient of friction is removably attached to the entire inner circumference of the flask body.