JPH065758U - Molten metal surface position measuring device - Google Patents

Abstract

(57) [Summary] [Purpose] To enable accurate position measurement of the molten metal surface using ultrasonic waves. [Structure] The molten metal 1 in the Toriho 2 is scooped by the robot 3.
In the one that was pumped in 4 and poured into the mold, an ultrasonic sensor 5 that emits ultrasonic waves toward the molten metal surface 1a and receives reflected waves from the molten metal surface 1a is attached to the ladle 4 mounting side of the robot 3. The temperature sensor 6 for detecting the ambient temperature of the ultrasonic sensor 5 is provided, and the time from the emission of the ultrasonic wave by the ultrasonic sensor 5 to the reception of the reflected wave and the ambient temperature detected by the temperature sensor 6 are provided. Distance conversion means 13 is provided for calculating the distance from the ultrasonic sensor 5 to the molten metal surface 1a based on the ultrasonic velocity corresponding to.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a molten metal surface position measuring device.

[0002]

[Prior art]

 In the one in which the molten metal in the hoho is drawn by a robot with a ladle and poured into a mold, in order to calculate the position of the molten metal drawn by the ladle, a contact-type sensor consisting of a metal rod protruding from the ladle mounting part of the robot is used. Some of them are provided so that the position of the molten metal surface can be detected. There is also a robot equipped with an optical sensor at the ladle mounting portion to optically measure the distance to the molten metal surface.

[0003]

[Problems to be solved by the device]

 However, the conventional contact type sensor has a problem that the molten metal adheres to the metal rod, and it becomes difficult to measure the position of the molten metal surface in a short period of use. Moreover, in the optical measurement method, since smoke is generated from the molten metal surface and the molten metal surface is ignited, the optical sensor is apt to malfunction and it is difficult to measure the distance accurately.

In view of the above-mentioned problems, the present invention is to make it possible to accurately measure the position of the molten metal surface using ultrasonic waves.

[0005]

[Means for Solving the Problems]

 The technical means of the present invention for solving this technical problem is to mount the ladle 4 of the robot 3 in such a manner that the molten metal 1 in the hoho 2 is drawn by the robot 3 with the ladle 4 and poured into the mold. An ultrasonic sensor 5 for emitting an ultrasonic wave toward the molten metal surface 1a and receiving a reflected wave from the molten metal surface 1a is provided on the part side, and a temperature sensor 6 for detecting the ambient temperature of the ultrasonic sensor 5 is provided. Based on the time from the emission of the ultrasonic wave by the ultrasonic sensor 5 to the reception of the reflected wave and the velocity of the ultrasonic wave corresponding to the ambient temperature detected by the temperature sensor 6, the molten metal from the ultrasonic sensor 5 is provided. The point is that the distance conversion means 13 for calculating the distance to the surface 1a is provided.

[0006]

[Action]

 When the molten metal surface position is not measured, cooling air is blown onto the ultrasonic sensor 5 by the cooling means, and the ultrasonic sensor 5 is cooled so that the characteristics of the ultrasonic sensor 5 are not deteriorated or damaged by the heat from the molten metal 1. At the time of measuring the position of the molten metal surface, the blowing of the cooling air by the cooling means is stopped, and the ultrasonic wave is emitted from the ultrasonic sensor 5 toward the molten metal surface 1a. This ultrasonic wave is reflected by the molten metal surface 1a, and the reflected wave is detected by the ultrasonic sensor 5. In this case, by stopping the blowing of the cooling air, it is possible to prevent the velocity of the ultrasonic waves emitted from the ultrasonic sensor 5 from varying due to the blowing of the cooling air. At this time, the temperature sensor 6 detects the ambient temperature of the ultrasonic sensor 5.

Then, the distance conversion means 13 inputs the detection signals from the ultrasonic sensor 5 and the temperature sensor 6, the time from the ultrasonic wave emission by the ultrasonic sensor 5 to the reception of the reflected wave, and the temperature sensor 6 The distance from the ultrasonic sensor 5 to the molten metal surface 1a is calculated from the ultrasonic velocity corresponding to the ambient temperature detected by.

[0008]

【Example】

 The present invention will be described below with reference to the illustrated embodiment. In FIG. 2, reference numeral 1 is a molten metal such as aluminum or solder, which is housed in a pulling hook 2. 3 is a robot, and a ladle 4 is attached to the tip end thereof, and under the control of the robot 3, the molten metal 1 in the pulling bar 2 is drawn by the ladle 4 and poured into the mold. An ultrasonic sensor 5 is provided on the ladle mounting side of the robot 3 and emits ultrasonic waves toward the molten metal surface 1a to receive reflected waves from the molten metal surface 1a. 6 is a temperature sensor that detects the ambient temperature of the ultrasonic sensor 5. Reference numeral 7 denotes an air pipe for blowing cooling air to the ultrasonic sensor 5.A pump or the like is provided at the base end side of the air pipe 7, and when the molten metal surface position is not detected, the air pipe 7 is driven by the pump or the like. The cooling air is blown from the ultrasonic sensor 5 toward the ultrasonic sensor 5 and is controlled so as to stop the blowing of the cooling air when measuring the molten metal surface position. In this case, cooling means for blowing cooling air to the ultrasonic sensor 6 is constituted by the air pipe 7 and the pump.

In FIG. 1, reference numeral 11 denotes a nuclear power generation unit, which is configured to output a nuclear power wave as shown in FIG. Reference numeral 12 is a shock wave drive unit, which inputs the primary wave of the primary unit 11 and outputs a shock wave as shown in Fig. 3 (b) at the rising edge of the primary wave, which is ultrasonically generated by the ultrasonic sensor 5 as ultrasonic waves. Fire it toward 1a. Reference numeral 13 is a distance calculation means for calculating the distance from the ultrasonic sensor 5 to the molten metal surface 1a. The reflected wave processing unit 15, the comparison unit 16, the distance detection logic unit 17, the temperature sensor amplifier unit 18, the clock generation unit 19, and the AND unit. The circuit 20 and the counter unit 21 are provided.

The reflected wave processing unit 15 inputs the detection signal from the ultrasonic sensor 5, finds the reflected wave of the ultrasonic wave, and outputs it to the comparison unit 16. The comparison unit 16 compares the signal of the reflected wave with the level setting value set by the level setting unit 23 to determine the time point when the reflected wave is received. The distance detection logic unit 17 inputs the signal of the primary wave from the primary generator unit 11 and the discrimination signal indicating the time when the reflected wave is received from the comparison unit 16, and the ultrasonic wave is detected as shown in FIG. It outputs a distance detection signal that has a high voltage between the time when the ultrasonic wave is emitted by the sensor 5 and the time when the reflected wave is received. The temperature sensor amplifier section 18 receives the detection signal from the temperature sensor 6, amplifies it, and outputs it to the clock generation section 19.

The clock generation unit 19 outputs a clock pulse as shown in FIG. 3D, in which the generation frequency changes according to the temperature detected by the temperature sensor 6. That is, the speed of the ultrasonic waves emitted from the ultrasonic sensor 5 fluctuates according to changes in the ambient temperature, and becomes faster when the ambient temperature becomes higher and slower when the ambient temperature becomes lower. The generation frequency of the clock pulse is increased as the ambient temperature rises so that the distance traveled by the ultrasonic waves at each generation is constant. Therefore, the distance from the ultrasonic sensor 5 to the molten metal surface 1a is counted by counting the number of clock pulses generated from the clock generation unit 19 from the time when the ultrasonic sensor 5 emits the ultrasonic wave to the time when the reflected wave is received. Can be calculated. While the distance detection wave shown in FIG. 3C is high voltage from the clock generation unit 19 through the AND circuit 20, the counter unit 21 outputs the clock from the clock generation unit 19 as shown in FIG. 3D. Input a clock pulse and count this clock pulse.

Reference numeral 26 denotes a display unit, which inputs a count signal from the counter unit 21 and digitally displays the distance from the ultrasonic sensor 5 calculated by the distance calculation unit 13 to the molten metal surface 1a. Reference numeral 27 denotes an upper limit comparison unit, which inputs a count signal from the counter unit 21 and compares the upper limit distance set by the upper limit setting unit 28 with the distance calculated by the distance calculation means 13. Reference numeral 29 denotes a lower limit comparison unit, which inputs a count signal from the counter part 21 and compares the lower limit distance set by the lower limit setting unit 30 with the distance calculated by the distance calculation unit 13.

Reference numeral 32 denotes a pumping position determination unit, which inputs a comparison signal from the upper limit comparison unit 27 and the lower limit comparison unit 29, and sets the upper limit setting for the distance from the ultrasonic sensor 5 to the molten metal surface 1a calculated by the distance calculation unit 13. When it is between the upper limit distance set by the unit 29 and the lower limit distance set by the lower limit setting unit 30, the robot 3 outputs a drive signal for causing the molten metal 1 in the pulling hoe 2 to be pumped by the ladle 4.

[0014]

[Effect of device]

 According to the present invention, it is possible to sufficiently compensate for the speed fluctuation of the ultrasonic wave due to the fluctuation of the ambient temperature, and to accurately measure the position of the molten metal surface 1a using the ultrasonic wave. You can Further, since cooling air is blown onto the ultrasonic sensor 5 to cool the ultrasonic sensor 5, even if the ultrasonic sensor 5 is mounted near the molten metal 1, the ultrasonic sensor 5 may be damaged by the heat of the molten metal 1. It disappears. Moreover, since the blowing of the cooling air is stopped when the position of the molten metal surface is detected, the blowing of the cooling air does not change the ultrasonic velocity and cause a measurement error.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a front view.

FIG. 3 is a time chart.

[Explanation of symbols]

 1 Molten metal 1a Molten metal surface 2 Pulling hoist 3 Robot 4 Ladle 5 Ultrasonic sensor 6 Temperature sensor 13 Distance calculation means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location G01S 15/08 9382-5J

Claims (2)

[Scope of utility model registration request] 1. The molten metal (1) in the hoho (2) is transferred to the robot (3).
With a ladle (4) for pouring into the mold with a ladle (4), the molten metal surface (1
An ultrasonic sensor (5) that emits ultrasonic waves toward (a) and receives reflected waves from the molten metal surface (1a) is provided, and a temperature sensor (6) that detects the ambient temperature of the ultrasonic sensor (5) is provided. ) Is provided, and the ultrasonic wave corresponding to the ambient temperature detected by the temperature sensor (6) and the time from the emission of the ultrasonic wave by the ultrasonic sensor (5) until the reflected wave is received, the ultrasonic wave A molten metal surface position measuring device comprising a distance conversion means (13) for calculating a distance from the sound wave sensor (5) to the molten metal surface (1a). 2. The ultrasonic sensor (5) is provided with cooling means for blowing cooling air, and the cooling air blowing by the cooling means is stopped when the position of the molten metal surface is detected. 1. The molten metal surface position measuring device according to 1.