JPH07226B2 - Controller for automatic pouring furnace - Google Patents

Description

Description: [Industrial application] The present invention relates to an automatic pouring furnace control device for automating a casting operation in a foundry.

[Prior Art] There are electromagnetic pump type, stopper type, pressurized tapping type, etc. as this kind of automatic pouring furnace, but tapping speed is fixed or stepwise pattern change, and tapping is performed based on the specified speed. is doing.

[Problems to be Solved by the Invention] However, there is a change with time peculiar to the pouring furnace due to wear of the pouring nozzle, adhesion of slag, or the like, which causes a change in the tapping speed, which causes an error in pouring accuracy. there were.

[Means for Solving Problems] The control device for an automatic pouring furnace according to the present invention includes a pouring furnace (4) through a sprue cup (5a) provided on an upper part of the mold (5). An apparatus for automatically pouring molten metal into a mold (5), a pouring amount setting means (1) for setting a pouring amount Q _o for a mold (5), and a level sensor (6) provided for detecting a molten metal level in a spout cup (5a). ), A reference level setting unit (7) for setting the molten metal level in the sprue cup (5a) as a level to be held, and the time for tapping from the pouring furnace (4) while maintaining the molten metal level at the reference level. Hot water discharge amount calculation unit (8) for calculating the hot water discharge amount Q _x from the mold to the mold (5)
And a signal addition unit (2) for obtaining the remaining pouring amount Q by subtracting the pouring amount Q _x from the pouring amount Q _o by the pouring amount setting unit (1), and the remaining pouring amount Q output from the signal adding unit (2) Is more than the specified amount, the air pressure to pressurize the pouring furnace (4) is controlled to keep the molten metal level in the sprue cup (5a) at the reference level, and the residual pouring amount Q becomes less than the specified amount. In that case, an air pressure calculation unit (3) for returning the air pressure to the atmospheric pressure is provided.

[Operation] When the amount of the remaining pouring metal is large, the molten metal level in the sprue cup is kept constant by the control of the air pressure calculation unit (3), so that the pouring from the sprue cup into the mold is performed at a constant speed. When the amount of remaining pouring is reduced and the pouring is about to end, the air pressure to the pouring furnace (4) is reduced to atmospheric pressure and the tapping is stopped. Even if there is, you can always tap the hot water at a constant speed. Further, since the amount of remaining hot water pouring is managed by the hot water discharge amount calculating means (8), proper pouring is performed to the mold (5).

[Embodiment] FIG. 1 is a system diagram showing one embodiment of a control device for an automatic pouring furnace according to the present invention. Reference numeral 1 denotes a pouring amount setting unit for setting the pouring amount to the mold 5, and the set pouring amount is input to the adding unit of the signal adder 2. Reference numeral 3 denotes an air pressure calculation unit for calculating the air pressure applied to the molten metal surface of the pressurizing pouring furnace 4, so that an appropriate pouring speed can be obtained in accordance with the remaining pouring amount given from the signal adder 2. A predetermined air pressure is calculated according to the remaining pouring amount as described later.

Reference numeral 5 denotes a mold, and an upper part of the mold 5 receives a molten metal from a pressurizing type pouring furnace 4 and guides it into the mold.
5a is formed. A level sensor 6 is provided to detect the molten metal level in the sprue cup 5a. The molten metal level in the sprue cup 5a is held at a constant reference level when pouring into the mold 5, and the reference level setting unit 7 sets the reference level. Spout cup
When the molten metal level in 5a is kept constant, the molten metal stored in the sprue cup 5a flows out to the mold 5 at a constant speed. Reference numeral 8 denotes a hot water discharge amount calculation unit that calculates the hot water discharge amount to the mold 5 from the product of the outflow speed and the hot water discharge time.

The control operation in the above system will be described below.

It is now assumed that the pouring amount setting unit 1 sets, for example, "100" as the pouring amount to the mold 5. At this time point, "0" is output from the hot water discharge amount calculation unit 8 as the hot water discharge amount, and thus "100" is supplied to the air pressure calculation unit 3 as the residual pouring amount. When the residual pouring amount is large like this time, the air pressure to the pressurizing pouring furnace 4 is set so that the molten metal level at the gate 5a detected by the level sensor 6 maintains the reference level set by the reference level setting unit 7. Is applied. This makes the sprue cup
The molten metal discharged to 5a flows out to the mold 5 with a constant flow rate Q _o . Therefore, the amount of hot water discharged to the mold 5 is calculated by the hot water discharge amount calculation unit 8 by multiplying the outflow time by Q _o . The calculated hot water discharge amount is supplied to the signal addition unit 2 one by one as a subtraction value. As a result, the residual pouring amount supplied to the air pressure calculation unit 3 gradually decreases from "100", but is almost "10".
Until, the melt level in the sprue cup 5a is maintained at the reference level.

Now, when the amount of the remaining pouring metal falls below “10”, the air pressure to the pressurizing pouring furnace 4 is released to the atmospheric pressure, so that the tapping of the pressurizing pouring furnace 4 is stopped soon, but after that, the spout cup The molten metal stored in 5a flows out into the mold 5, so that the molten metal is poured into the mold 5 without excess or deficiency.

When the molten metal level of the mold 5 is detected, the level detection tends to be unstable if the molten metal surface is wavy. Therefore, as shown in FIG. 2, if the bottom surface of the spout cup portion corresponding to the sensor detection portion of the mold 5 is formed with stairs 5b, the molten metal level can be detected stepwise even if the molten metal surface is wavy. Even if the hot water discharge level is lowered and the burning part remains in the sprue cup part, it can be caught by the area of the step lock, so that stable level detection can be obtained due to the characteristics of the sensor.

Although the pressurization type pouring furnace is used in the above embodiment, the tilting angle of the tilting pouring furnace may be changed according to the pouring speed.

[Effects of the Invention] As described above, at a stage where the amount of remaining pouring metal is large, the molten metal level in the sprue cup is kept constant in order to keep the dropping speed from the sprue cup to the mold constant, and the pouring is almost finished. In this case, the air pressure was reduced to stop the tapping, so even if there is wear or slag adhesion on the pouring nozzle, the tapping can always be tapped at a constant speed, so a casting without defects can be provided, and Since the amount of remaining hot water is controlled by the amount of hot water discharge calculation means, proper hot water pouring can be performed without excess or shortage.

[Brief description of drawings]

Fig. 1: System diagram showing one embodiment of control device for automatic pouring furnace of the present invention Fig. 2: Cross-sectional view showing modified example of mold in Fig. 1 ... pouring amount setting unit, 2 ... signal Addition part 3 ... Air pressure calculation part, 4 ... Pressurized pouring furnace 5 ... Mold, 5a ... Gate cup 5b ... Stairs part, 6 ... Level sensor 7 ... Reference level calculation part, 8 ... Out Hot water calculation unit

Claims (1)

[Claims] 1. A device for automatically pouring a molten metal into a casting mold (5) by means of a pouring furnace (4) through a sprue cup (5a) provided on the upper part of the casting mold (5). A pouring amount setting means (1) for setting Q _o , a level sensor (6) provided for detecting the melt level in the spout cup (5a), and a level at which the spout cup (5a) should hold the melt level Level setting unit (7) to set as, and the pouring furnace (4) with the molten metal level kept at the reference level
From a more leaving water time and mold tapping quantity calculator for calculating the hot water amount Q _x to (5) (8), pouring amount setting unit (1) by pouring amount Q residual by subtracting the amount of hot water Q _x out _o pouring amount When the amount Q of the signal addition unit (2) for obtaining Q and the amount Q of the remaining molten metal output from the signal addition unit (2) is equal to or more than the specified amount, the molten metal level in the spout cup (5a) should be kept at the reference level. An air pressure calculation unit (3), which controls the air pressure applied to the pouring furnace (4) and returns the air pressure to the atmospheric pressure when the residual pouring amount Q becomes equal to or less than a specified amount.
And a controller for an automatic pouring furnace.