JPH05305387A - Metallic mold for casting - Google Patents

Abstract

PURPOSE:To remove gas and foreign material of small sp. gr. in molten metal. CONSTITUTION:In a metallic mold used to a gravity casting, a vertical runner 1 for guiding the molten metal into a cavity 7, filter 3, contructing part 4, horizontal runner 5 and gate 6 are formed and at the upper part of the filter 3 and the upper part of the contructing part 4, gas traps 11, 13 communicating to outside of the metallic mold are arranged. Further, on a slag trap 14 at the end part of the horiozontal runner going over the gate 6, a foreign material trap 15 is formed upward, and by these gas traps 11, 13 and the foreign material trap 15, the gas and the foreign material of small sp. gr. in the molten metal can be collected at the same time.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a mold for gravity casting.

[0002]

2. Description of the Related Art The so-called gravity casting method, in which a high-temperature molten metal is poured into a cavity by gravity, is used to form a highly accurate casting product, and in particular, a mold having high thermal conductivity is used. It is suitable for rapidly cooling the molten metal to obtain a cast product having a fine structure and high strength.

However, in this casting method, the high temperature molten metal in a turbulent state flows down from the vertical runner to the horizontal runner at a high temperature. Can get into the cavity and cause foreign matter to get caught.

In order to solve such a problem, until now, the horizontal runner has been lengthened to collect the foreign matter, but even if such a measure is taken, the foreign matter having a small specific gravity is collected. Without flowing into the cavity together with the molten metal, causing the problems described above.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to:
An object of the present invention is to provide a new casting mold capable of reliably collecting all foreign matters having a small specific gravity.

[0006]

[Means for Solving the Problems] That is, the present invention provides a casting mold for achieving the above-mentioned object, in which the horizontal runner from the lower end of the vertical runner of the mold to the gate is outside the mold. A gas trap communicating with the above is formed upward, and a foreign matter trap for collecting foreign matter having a small specific gravity is formed above the slag trap extending beyond the gate portion.

[0007]

EXAMPLES Examples of the present invention will be described below. The drawings show an embodiment of the present invention. A vertical runner 1 having an upper end communicating with a sprue (not shown) is formed in a mold body for gravity casting, and a lower end thereof branches into a horizontal runner. Then, from here, it communicates with the filter 3 made of porous ceramics through the squeezing portion 2, and further with the horizontal runner 5 through the squeezing portion 4, and from here through the gate 6 to correspond to the shape of the cast product. It is formed so as to be connected to the lower end of the cavity 7.

On the other hand, in the mold thus constructed, a gas trap 11 communicating with the gas slit 10 is further formed above the filter 3, and a gas slit 12 is provided above the squeezing portion 4. Cavity nesting closeout 8
A gas trap 13 extending into the gap between
The gas trapped by the molten metal, etc.
The slag trap 14 at the terminal end of the horizontal runner 5 that extends over the gate 6 while being collected by means of 3 is provided with a foreign matter trap 15 for collecting foreign matter having a smaller specific gravity than the molten metal.

Therefore, When the molten metal in a turbulent state at a high temperature is introduced into the vertical runner 1 at high speed from the sprue of the mold configured as described above, the molten metal causes a foreign substance such as a mold coating agent, slag, or a molten metal in the vertical runner 1, Entrains the surrounding gas to reach the lower end thereof, and further enters the inside of the filter 3 where the slag and oxide slag are removed and rectified to flow into the cavity 7, while being entrained in the molten metal. The collected gas is collected by the gas trap 11 when the molten metal is rectified in the filter 3, and then flows out of the mold through the gas slit 10. Similarly, the molten metal is contracted in the downstream squeezing portion 4. Even when receiving the action, the gas in the molten metal is collected by the gas trap 13 above the molten metal, and is discharged to the outside through the gap between the cavity insert partition 8 and the gas trap.

On the other hand, the foreign matter having a small specific gravity, which is not collected by the filter 3 and gathered at the tip of the molten metal, is not pushed into the cavity 7 by the molten metal flow and does not enter the cavity 7. It flows into 14 together with the slag, where it is separated from the slag and collected in a foreign matter trap 15 above it.

Therefore, the molten metal flows into the cavity 7 after removing most of the slag and gas including foreign matter having a small specific gravity in the process of flowing through this portion, and there is no foreign matter such as foreign matter and pinholes. Will form a good casting.

[0012]

As described above, according to the present invention, a gas trap communicating with the outside of the mold is formed upward in the horizontal runner portion extending from the lower end of the vertical runner to the gate portion, and the gate portion is formed. At the upper part of the slag trap that extends beyond, a foreign substance trap that collects foreign substances with small specific gravity was formed, so in the process of flowing into the horizontal runner and rectifying it, the gas separated from the molten metal The gas trap can quickly collect the foreign matter having a small specific gravity together with the slag and drive it into the slag trap to separate it from the slag and collect it in the upper foreign matter trap. Can be reliably suppressed, and a better cast product free from foreign matter and gas defects can be formed.

[Brief description of drawings]

FIG. 1 is a view showing a main part of a mold that constitutes an embodiment of the present invention.

[Explanation of symbols]

 1 Vertical runner 5 Horizontal runner 6 Gate part 7 Cavity 11, 13 Gas trap 14 Slag trap 15 Foreign matter trap

Claims (1)

[Claims] 1. A mold used for gravity casting,
A gas trap communicating with the outside of the mold is formed upward in the horizontal runway portion from the lower end of the vertical runway of the mold to the gate part, and the upper part of the slag trap extended beyond the gate part. A metal mold for casting, characterized in that a foreign matter trap for collecting foreign matter having a small specific gravity is formed on.