JPH0733137Y2 - Level detector for temperature rising furnace - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a molten metal hot water that is kept in a temperature rising furnace suitable for use in an instant melting apparatus for an aluminum-based metal ingot (hereinafter referred to as an aluminum ingot). A device for detecting a surface level.

[Prior Art] When casting a molten aluminum-based metal as a member of machinery, electric equipment, etc. by die casting, etc.,
There is an instantaneous melting device as a device for continuously and quickly melting an aluminum ingot, raising the temperature of the molten metal to an appropriate temperature, and tapping the molten metal. The heating furnace used for this instantaneous melting device is shown in FIG. explain.

FIG. 2 shows the entire instant melting apparatus. In this figure, 1 is a cold material insertion guide, which is an aluminum ingot (hereinafter, referred to as a material).
Called cold material. ) 2 is guided upright into the melting furnace 3 and the molten metal melted in the melting furnace 3 is prevented from scattering outside. The melting furnace 3 is made of a refractory material and has a hollow cylindrical shape with an upright bottom, in which the cold material 2 can be stored in an upright state, and a furnace body 31 for heating and melting the cold material 2 from its surface. The induction coil 32 is provided on the outer periphery of the furnace, and the outlet 33 is opened in the bottom wall of the furnace body 31. Reference numeral 4 denotes a heating furnace coaxially arranged below the melting furnace 3, which is made of refractory material and has a hollow cylindrical furnace body 41 with an upright bottom, and a furnace body 41 for raising the temperature of the molten metal to an appropriate temperature.
It comprises an induction coil 42 provided on the outer periphery of the furnace and an outlet 43 opened in the bottom wall of the furnace body 41. Reference numeral 5 denotes a hollow tubular hot water outlet pipe which surrounds the outlet 43 and extends downward and communicates with the temperature raising furnace 4, and a hot water outlet 51 is provided below the hollow hot water outlet pipe 5. 6
Is an electromagnetic pump arranged on the outer circumference of the tapping pipe 5 and above the tapping port 51, so that upward thrust can be applied to the molten metal in the tapping pipe 5.

Then, the cold material 2 sent into the melting furnace 3 in an upright state by the guide of the cold material insertion guide 1 is heated by the action of the induction coil 32 and melted from its surface into a molten metal, and this molten metal is the outlet. Outflow from 33 to heating furnace 4, and further outflow port 43
And flows into the hot water outlet pipe 5. And the electromagnetic pump 6
Is operated to give an upward thrust to the molten metal that has flowed into the molten metal outlet pipe 5 so that the molten metal does not flow out of the molten metal outlet 51, and the induction coil 42 is energized so that the molten metal enters the temperature raising furnace 4. It accumulates and is kept at the proper temperature. Further, when pouring the molten metal into a die cast machine or the like, if the operation of the electromagnetic pump 6 is stopped and the upward thrust applied to the molten metal in the tap pipe 5 is eliminated, the molten metal descends by its own weight, The hot water is discharged from the hot water outlet 51 to a die cast machine or the like (not shown).

Next, the molten metal level detecting device for the temperature rising furnace 4 as described above will be described with reference to FIG. In FIG. 3, those having the same symbols as those of the temperature raising furnace shown in FIG. 2 have the same configuration as that of FIG.

In FIG. 3, reference numeral 71 denotes a bottom electrode, which is provided in the vicinity of the outlet 43 of the temperature raising furnace 4 so as to come into contact with the molten metal 44. 72 and 73 are molten metal level detection electrodes, which are above the inner wall of the furnace body 41 (upper limit line of molten metal) and below the inner wall (lower limit line of molten metal), respectively.
It is provided so that it can contact the molten metal 44. Reference numerals 82 and 83 are detection lamps provided outside the temperature raising furnace 4 and are electrically connected to the molten metal level detection electrodes 72 and 73, respectively. A power source 9 has one pole connected to each of the detection lamps 82 and 83, and the other pole connected to the bottom electrode 71.

Then, before the cooling material 2 is melted in the melting furnace 3 shown in FIG. 2 or in a state where the molten metal flows out from the outlet 43 and the molten metal is hardly accumulated in the temperature raising furnace 4. Since the circuit constituted by the power source 9, the bottom electrode 71 and the molten metal level detecting electrode 72 or the molten metal level detecting electrode 73 is open, both the detection lamps 82 and 83 are turned off. Next, the melting of the cold material 2 progresses in the melting furnace 3 shown in FIG. 2, the amount of the molten metal 44 accumulated in the temperature rising furnace 4 increases, and the level of the molten metal 44 in the temperature rising furnace 4 rises. Rise, and when the molten metal 44 contacts the molten metal level detecting electrode 73, the molten metal level detecting electrode 73 and the bottom electrode 71 are energized by the molten metal 44, and the power source 9, the bottom electrode 71 and the molten metal level detecting electrode 73 Since the configured circuit is closed, a current flows through the detection lamp 83, and the detector lamp 83 lights up. And the surface of the water rises further,
When the molten metal contacts the molten metal level detecting electrode 72, the molten metal level detecting electrode 72 and the bottom electrode 71 are energized by the molten metal, and the circuit composed of the power source 9, the bottom electrode 71 and the molten metal level detecting electrode 72 is closed. Therefore, a current flows through the detection lamp 82, and the detector lamp 82 lights up.

[Problems to be solved by the device]

By the way, in the above-mentioned conventional level detecting device of the temperature rising furnace, the molten metal is caught at the tip of the level detecting electrode and solidifies, but in the process of this solidification, a nearby slag is entrained in a semi-solidified state. , An intermediate solidified body containing a noro component and which can be called an intermediate between metal and noro is formed, and especially when the molten metal level is lowered, the lower side of this intermediate solidified body is always in contact with the molten metal to supply heat. Therefore, the intermediate solidified body easily grows, and in some cases, the icicles may grow so as to lower. The intermediate solidified body thus produced is not used as a molten metal but adheres to the side wall of the furnace or the like and becomes an unnecessary substance, and is thus called a slag in a broad sense.
Since this intermediate solidified body has a certain degree of conductivity, the molten metal level detection electrode and the molten metal surface are electrically connected through this intermediate solidified substance, and the molten metal melt level is detected by the molten metal level detection electrode. A circuit is formed between the molten metal level detecting electrode and the bottom electrode even below, and a detection lamp corresponding to the molten metal level detecting electrode is lit. That is, in the conventional molten metal level detecting device, there is a problem that slag adheres to the molten metal level detecting electrode and the detection operation becomes inaccurate.

The present invention has been made to solve this problem, and an object thereof is to obtain a molten metal level detecting device for a heating furnace in which no slag adheres to the molten metal level detecting electrode.

[Means for Solving the Problems]

In order to achieve the above object, in the present invention, a recess is formed in the inner wall of the temperature rising furnace in which each of the molten metal level detection electrodes is arranged, and the molten metal level detection electrode is provided in this concave portion from the bottom of the recessed portion. It is inserted so that it does not project and can come into contact with the molten metal in the temperature rising furnace.

[Operation] In the molten metal level detecting device of the present invention, since the tip of the molten metal level detecting electrode does not protrude from the bottom surface of the recess, the molten metal does not get caught on the molten metal level detecting electrode tip and solidifies, thus forming a slag. It will not be done.

[Embodiment] Next, an embodiment of the present invention will be described with reference to FIG. In FIG. 1, those having the same symbols as those shown in FIG. 3 have the same configuration as that of FIG.

The molten metal level detection electrodes 72, 73 are recessed portions 72a, 73a formed in the inner wall portion of the temperature rising furnace 4, respectively, and their tips are formed in the recessed portions 72a, 73a.
It is inserted so that it does not protrude from the bottom surface of a, 73a and that it can contact molten metal 44.

[Effects of the Invention] As described above, according to the present invention, a concave portion is formed in the inner furnace wall portion of the temperature raising furnace, and the molten metal level detection electrode is formed in the concave portion so that the tip thereof does not protrude from the bottom surface of the concave portion. Since it has been inserted, the molten metal is caught at the tip of the molten metal level detection electrode and solidifies, and this does not entrap nearby slag, forming a broad slag as a solidified body of the metal and slag intermediate. It has an excellent effect that the level can be detected.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a temperature rising furnace having a molten metal level detecting device according to the present invention, FIG. 2 is a vertical sectional side view of an instant melting device, and FIG. 3 is a heating furnace having a conventional molten metal level detecting device. It is a vertical side view of FIG. 4 …… Raising furnace 9 …… Power supply 44 …… Molten metal 71 …… Bottom electrode 72,73 …… Melting surface level detection electrode 72a, 73a …… Concave 82,83 …… Detector

Claims (2)

[Scope of utility model registration request] 1. A molten metal supplied from a melting furnace for melting aluminum or an aluminum-based alloy to raise the temperature to a predetermined temperature, and usually reaches a predetermined upper limit of the molten metal surface to an external casting mold or the like. As a heating furnace for pouring, a bottom electrode arranged near the bottom of the heating furnace and in contact with the molten metal,
A plurality of molten metal level detection electrodes which are arranged at predetermined intervals in the vertical direction on the side wall of the heating furnace and which are in contact with the molten metal in the heating furnace at each position, and the outside of the heating furnace. And a detector electrically connected to each of the molten metal level detection electrodes, and a power source having one pole connected to the detector and the other pole connected to the bottom electrode. And a molten metal level detecting electrode for detecting the presence of molten metal at each position by energizing each of the molten metal level detecting electrodes; a position where each molten metal level detecting electrode on the side wall of the temperature raising furnace is arranged. In the temperature rising furnace, a recess is formed, and the tip of each of the molten metal level detection electrodes is inserted into the bottom of the recess so as not to project inward beyond the bottom of the recess. Level level detector. 2. A molten metal level detecting apparatus for a temperature rising furnace according to claim 1, wherein the melting furnace is an instantaneous melting furnace used for an aluminum ingot instantaneous melting apparatus. Surface level detector.