JPH03200020A - Molten bath level detector for temperature raising furnace - Google Patents

Abstract

PURPOSE:To accurately detect the molten bath level by forming a pair of molten bath level detecting electrodes and supplying current to these electrodes. CONSTITUTION:When molten metal 44 comes into contact with the electrodes 11a, 11b, current is supplied to the electrodes 11a, 11b by the molten metal 44, a circuit constituted of the electrodes 11a, 11b and a detection lamp 14b is closed, voltage is impressed from a power supply 9 to the circuit through an insulating transformer 15b, and current flows into the lamp 14b to turn on the lamp 14b. When the molten bath level is raised further and the molten metal 44 comes into contact with the electrodes 10a, 10b, current is supplied to the electrodes 10a, 10b by the molten metal 44 and a circuit constituted of the electrodes 10a, 10b and a lamp 14a is closed, so that voltage is impressed from the power supply 9 to the circuit through an insulating transformer 15a and current flows into the lamp 14a to turn on the lamp 14a.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing molten metal heated in a heating furnace suitable for use in an instant melting apparatus for aluminum-based metal ingots (hereinafter referred to as aluminum ingots). The present invention relates to a device for detecting surface level.

[Prior art] When molding molten aluminum metal into parts for machines, electrical equipment, etc. by die-casting,
An instant melting device is a device that rapidly and continuously melts an aluminum ingot, raises the temperature of the molten metal to an appropriate temperature, and taps out the molten metal. explain.

Figure 2 shows the entire instant melting device. In this figure, 1 is a cypress material insertion guide, and the material is an aluminum ingot (hereinafter referred to as
It is called cypress wood. ) 2 into the melting furnace 3 in an upright state and prevents the molten metal melted in the melting furnace 3 from scattering outside. The melting furnace 3 includes a furnace body 31 that is made of a refractory material and has an upright hollow cylindrical shape with an eave, and is capable of storing the cypress material 2 in an upright state, and a furnace body 3 that heats and melts the cypress material from its surface.
It consists of an induction coil 32 provided on the outer periphery of the furnace body 31 and an outflow 033 opened in the bottom wall of the furnace body 31. Reference numeral 4 denotes a heating furnace disposed coaxially below the melting furnace 3, which includes an upright hollow cylindrical furnace body 41 with an eave made of refractory material, and a heating furnace 41 on the outer periphery of the furnace body 41 for heating the molten metal inside to an appropriate temperature. It consists of an induction coil 42 provided and an outlet 43 opened in the bottom wall of the furnace body 41. Reference numeral 5 designates a hollow tubular tapping pipe that surrounds the outlet 43 from the outside, extends downward, and communicates with the heating furnace 4, and below it is a tapped tap 51.
is provided. 6 is the outer periphery of the hot water tap 5, and the hot water tap 51
An electromagnetic pump placed higher up can apply upward thrust to the molten metal in the tapping pipe 5.

Then, the cypress material 2 is sent into the melting furnace 3 in an upright state under the guidance of the cypress material insertion guide]-, which is heated by the action of the induction coil 32 and melted from its surface to become molten metal.
This molten metal flows out from the outflow 033 to the heating furnace 4, further passes through the outflow 043, and flows into the tapping pipe 5. Then, by operating the electromagnetic pump 6 to apply an upward thrust to the molten metal that has flowed into the tapping pipe 5 to prevent the molten metal from flowing out from the tapping port 51, and by energizing the induction coil 42, the molten metal will rise. It is stored in the hot furnace 4 and kept at an appropriate temperature. Also,
When pouring molten metal into a die-casting machine, etc., by stopping the operation of the electromagnetic pump 6 and eliminating the upward thrust applied to the molten metal in the tapping pipe 5, the molten metal will descend under its own weight.
Output from the outlet 51 to a die-cast machine, etc. (not shown)!
be done.

Next, the above-described hot water level detection device for the heating furnace 4 will be explained using FIG. 3. In FIG. 3, those having the same symbols as the heating furnace shown in FIG. 2 have the same construction as those in FIG. 2.

In FIG. 3, reference numeral 71 denotes a bottom electrode, which is provided near the outlet 43 of the heating furnace 4 so as to be in contact with the molten metal 44. 72.
Reference numeral 73 denotes a melt level detection electrode, which is provided above the inner wall (upper limit line of the melt level) and below the inner wall (lower limit line of the melt level) of the furnace body 41 so as to be able to contact the molten metal 44, respectively.

Detection lamps 82 and 83 are provided outside the heating furnace 4, and are electrically connected to the hot water level detection electrodes 72 and 73, respectively. 9 is the power supply, and one pole is the detection lamp 82
．． 83, and the other pole is connected to the bottom electrode 71.
is connected to.

Then, before the cypress material 2 is melted in the melting furnace 3 shown in FIG. Power supply9. Since the circuit consisting of the bottom electrode 7] and the hot water level detection electrode 72 or the full level detection electrode 73 is closed, the detection lamps 82 and 83
All lights are off. Next, the melting of the cypress material 2 progresses in the melting furnace 3 shown in FIG. rises and when the molten metal 44 comes into contact with the molten metal level detection electrode 73, the molten metal energizes the molten metal level detection electrode 73 and the bottom electrode 71. Since the circuit is closed, current flows through the detection lamp 83, and the detection lamp 83 lights up.

Then, when the molten metal level rises further and the molten metal contacts the molten metal level detection electrode 72, the molten metal 44 energizes the molten metal level detection electrode 72 and the bottom electrode 71, and the power source 9. Since the circuit constituted by the bottom electrode 71 and the hot water level detection electrode 72 is closed, current flows through the detection lamp 82 and the detection lamp 82 is turned on.

[Problem to be solved by the invention]

By the way, in the heating furnace equipped with the above-mentioned molten metal level detection device, the molten metal often adheres to the furnace wall and hardens, forming a slag 70, and the slag that has landed on the vortex surface level detection electrode rises up to 10,000.・As the molten metal grows downwards in the furnace, the molten metal level detection electrode and the molten metal surface are electrically connected by the slag, and even if the molten metal surface is below the molten metal surface level detection electrode, the molten metal surface level is not reached. A circuit is configured between the detection electrode and the bottom electrode,
There has been an inconvenience in that the detection lamp corresponding to this hot water level detection electrode lights up. That is, in the conventional hot water level detection device, there was a problem that 70 adhered to the hot water level detection electrode, making the detection operation inaccurate.

This invention is based on the fact that experience has shown that there is a bias in the adhesion of 70 to the inner wall of a heating furnace, and in particular, that 70 hardly adheres to the inner wall radially opposite to the inner wall to which 70 is attached. It is an object of the present invention to provide a device that can accurately detect the hot water level based on the following.

[Means to solve the problem]

In order to achieve the above object, the temperature rising furnace molten metal level detection device according to the present invention is arranged at a position corresponding to a desired molten metal level on the inner wall of the temperature rising furnace so as to be able to come into contact with the molten metal in the temperature rising furnace. (A first electrode formed by this method, and a second electrode formed on an inner wall radially opposite to the inner wall on which the first electrode is arranged, and which is arranged so as to be able to come into contact with the molten metal in the temperature rising furnace at each position.
an electrode, a detector disposed outside the heating furnace and connected to a circuit connecting the 111th pole and the 2'@pole, and connecting the 1st electrode, the detector, and the 2'@pole. It consists of a power supply capable of applying a voltage to a connected circuit, and the level of the hot water level is detected by energizing the first electrode and the second electrode.

For reasons described later, it is effective to insert the hot water level detection electrode into a recess formed in the inner wall of the heating furnace so that its tip does not protrude from the bottom of the recess.

In addition, when there are multiple desired hot water levels, the first
A plurality of pairs of hot water level detection electrodes each consisting of an electrode and the second electrode are arranged vertically at a predetermined interval, and each of the circuits connecting the first electrode and the second electrode is insulated with a detector. It is preferable to connect the transformers in series and connect each isolation transformer in parallel to one power supply.

[Function] In the above configuration, when the molten metal level in the heating furnace rises due to the supply of molten metal and the molten metal comes into contact with both of the pair of molten metal level detection electrodes, the circuit constituted by these electrodes is activated. Since the circuit is closed, current flows from the power supply through the transformer to the detector, which lights up, for example, if the detector consists of a lamp.

Therefore, it can be seen that the hot water level is ten times higher than the pair of hot water level detection electrodes. Furthermore, when the melt level falls due to the outflow of the molten metal and no longer makes contact with both of the pair of melt level detection electrodes, the circuit made up of one of these electrodes is opened, and current no longer flows to the detector. For example, if this detector consists of a lampshade, it will turn off. Therefore, it can be seen that the hot water level is below the hot water level detection electrode. In addition, 70 is attached to one of the paired hot water level detection electrodes, and even if this electrode and the hot water surface are electrically connected (regardless of the hot water level), it is possible to 70 is hardly attached to the inner wall of the electrode, so 70 is attached to the other electrode.
There is almost no possibility that 0 will be attached, so there will be no electrical connection between the pair of electrodes, and even if 70 is attached to one of the electrodes, the detector will hardly malfunction.

Note that if the tip of the electrode is arranged so that it does not protrude from the bottom of the recess, it becomes difficult for the electrode 70 to adhere to the electrode, so that there is almost no possibility that the detector will malfunction.

Embodiment E] Next, an embodiment of the present invention will be described with reference to FIG. In FIG. 1, the parts with the same reference numerals as those of the heating furnace shown in FIG. 2 have the same configurations as those in FIG. 2.

In Fig. 1, 10a and lla are the 11th holes for detecting the hot water level.
At the poles, the tips of the recesses 12a and 13a are formed above the inner wall (the upper limit line of the hot water level) and below the inner wall (the lower limit line of the hot water level) of the furnace body 41, respectively.
Make sure that the molten metal 44 does not protrude from the bottom surface of 13a.
It is inserted so that it can be contacted. 10b and llb are second electrodes for detecting the hot water level, and are located in the recesses 12a and 1, respectively.
A recess 12b formed in an inner wall radially opposite to 3a.
, ], 3b, the tip thereof is this recess 12b.

13b so that it does not protrude from the bottom surface of the melt 184.
It is inserted so that it can come into contact with 4. Between each of the first electrodes 10a, lla and the second electrodes 10h, 11b, a detection lamp 14a is provided outside the heating furnace 4,
14b and an isolation transformer 15a.

15b are connected in series, and the isolation transformer 15a.

15b are connected to the power supply 9 in parallel.

Next, an explanation will be given of the operation when the heating furnace having the above-described molten metal level detection device is used in an instantaneous melting device.

Before the cypress material 2 is melted in the melting furnace 3, the first electrode 1
0a, the circuit composed of the second electrode 10b and the detection lamp 14a, and the circuit composed of the first electrode 11a, the second electrode 11b and the detection lamp 14b are all open circuits, so the detection lamps 14a and 14b are both open. The lights are also off.

Next, the melting of the cypress material 2 progresses in the melting furnace 3 shown in FIG. rises, and the molten metal 44 becomes the first
When the electrode 11a and the 2'F4 pole 11b are contacted, the first electrode 11a and the second electrode 11b are energized by the molten metal, and the 18th pole 11a is formed.

Since the circuit consisting of the second electrode 11b and the detection lamp 14b is opened, voltage is applied to this circuit from the power supply 9 via the isolation transformer 15b, current flows to the detection lamp 14b, and the detection lamp 14b lights up. do. and,
When the molten metal level further rises and the molten metal 44 contacts the eleventh electrode 10a and the second electrode 10b, the first electrode 10a and the second
The electrode 10b is energized by the molten metal, and the first t4 poles 10a,
Since the circuit consisting of the second electrode 10b and the detection lamp 14a is opened, voltage is applied to this circuit from the power supply 9 via the isolation transformer 15a, current flows to the detection lamp 14a, and the detection lamp 14a lights up. do.

Here, since the first electrode 10a and the second electrode lQb are set to the upper limit line of the hot water level, and the first electrode 11a and the second electrode 11b are set to the lower limit line of the hot water level, the detection lamps 14a and 14b are turned on.・The following can be determined by the off state.

■Detection 7Fs 14a and 14b are both off: The hot water level in the heating furnace 4 is below the lower limit line, and there is a necessary force of 5 to start melting the cypress material 2 in the melting furnace 3 shown in No. 211.

■ Only the detection lamp 14b is lit: The hot water level 1 of the heating furnace 4 is between the lower limit line and the upper limit line.

■Both detection lamps 14a and 14b are lit: The melt level in the heating furnace 4 is above the upper limit line, and the melting furnace 3 shown in FIG.
There is a necessary force to stop the melting of the Japanese cypress wood 2.

And the level of the molten metal 44! The first electrodes 10a, lla and the second electrodes 10b,
llb has concave portions 12a, 13a, and 1 at its tips, respectively.
Since it does not protrude from the bottom of 2b and 13b, the molten metal 44
gets caught on these electrodes and hardens, which causes 70
is never formed. However, for example, the first electrode 10
70 is formed on the inner wall around a, and the hot water level is at this 1':4
If it is below pole 10a, the first
The 0a2 molten metal 44 may be electrically connected, but since 70 is not formed on the second electrode 10b corresponding to this first electrode 10a, this 174th pole 10a and the second
The electrode 10b is not energized and the detection lamp 14a is not erroneously turned on.

In addition, in the above embodiment, the first electrode and the corresponding second @
Although a pair of hot water level detection electrodes consisting of poles are provided on the upper limit line and the lower limit line, they may be provided on the inner wall corresponding to other levels at which the hot water level is to be detected.

[Effects of the Invention] As explained above, in the present invention, a pair of hot water level detection electrodes are provided on the inner wall corresponding to the desired hot water level and on the inner wall radially opposite to this inner wall, Since the hot water level is detected by energizing these electrodes, the following four excellent effects are achieved.

- Even if slag is formed on one of the female-sized hot water level detection electrodes and this electrode and the hot water level are electrically connected,
Since no current is applied between these electrodes unless the hot water level is above the pair of hot water level detection electrodes, the formation of 70 eliminates the possibility of inaccurate detection.

(2) If the tip of the electrode is arranged so that it does not protrude from the bottom of the recess, it becomes difficult for the electrode 70 to adhere to the electrode, so there is almost no chance of the detector malfunctioning.

■If the configuration is such that a voltage is applied from a power supply between a pair of hot water level detection electrodes via an isolation transformer, only one power source is required even if there are multiple pairs of hot water level detection'':!i poles.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional side view of a heating furnace having a hot water level detection device according to the present invention, Fig. 2 is a longitudinal sectional side view of an instant melting device, and Fig. 3 is a heating furnace having a conventional hot water level detection device. FIG. 4...Temperature rising furnace lQa, lla. 1, Ob, llb. 1.2a, 12b. 14a, 1.4b, 15a, 15b- 9... Power supply, first electrode, second electrode 13a, 13b', detector - insulation transformer 44, molten metal, recess

Claims (1)

[Claims] 1. The molten metal in the heating furnace is placed at a position corresponding to the desired level of the molten metal on the inner wall of a heating furnace that keeps the molten metal such as aluminum metal ingot warm and raises the temperature to an appropriate temperature. a first electrode configured to be in contact with the molten metal in the heating furnace; two electrodes, a detector arranged outside the heating furnace and connected to a circuit connecting the first electrode and the second electrode, and a circuit connecting the first electrode, the detector, and the second electrode. 1. A hot water level detection device for a heating furnace, comprising: a power supply capable of applying a voltage to the heating furnace; 2. The heating furnace according to claim 1, wherein each of the first electrode and the second electrode is inserted into a recess formed in the inner wall of the heating furnace so that its tip does not protrude from the bottom of the recess. Hot water level detection device. 3. Pairs of hot water level detection electrodes consisting of a first electrode and a second electrode are arranged in plural pairs at a predetermined interval in the vertical direction, and each in a circuit connecting the first electrode and the second electrode. 3. The hot water level detection device for a heating furnace according to claim 1, wherein a detector and an isolation transformer are connected in series, and each of the isolation transformers is connected in parallel to one power source.