JP2004216447A - Molten metal supplying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molten metal supplying method by delicately performing supply of the molten metal as a material for casting into a pouring pot attached to a die for casting by tilting the pouring pot at almost 90°. <P>SOLUTION: The height of the surface of the molten metal 90 supplied into the pouring pot 18 is measured at each prescribed time so as to bring the surface of the molten metal 90 into momentary contact with a detecting bar 11 beforehand raised and the supplying speed of the molten metal 90 from the displacing amount of the height before and after measuring and the prescribed time, is calculated, and the operating speed of the molten metal supplying apparatus 20 for supplying the molten metal 90 into the pouring pot 18 is controlled according to the supplying speed. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a hot water supply method, and more particularly, to a method of supplying molten metal to a ladle attached to a mold that is cast by being rotated approximately 90 degrees, for example.
[0002]
[Prior art]
Conventionally, there has been provided a method of performing casting by rotating a mold by approximately 90 degrees. A ladle is provided integrally with this mold, and a predetermined amount of molten metal, which is a material for casting, is supplied to the ladle before the mold is rotated approximately 90 degrees. Has become. The predetermined amount is obtained by measuring the height of the molten metal surface by laser distance measurement (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP-A-6-241861 (pages 2 to 4, FIGS. 1 to 3)
[0004]
[Problems to be solved by the invention]
However, the above-described laser ranging employs, for example, the principle of triangulation, but while the molten metal is supplied, the surface of the molten metal is minute but wavy, and the reflected light of the laser is constant. However, the measurement of the level of the molten metal (and thus the supply of molten metal) based on the principle of triangulation cannot avoid large errors.
[0005]
Therefore, the present invention does not provide a hot water supply method capable of precisely supplying a molten metal of the casting material to a ladle attached to a mold to be cast by being rotated by about 90 degrees. Is the subject.
[0006]
[Means for Solving the Problems]
Means taken to solve the above-mentioned problem is that "a hot water supply for supplying a molten metal of a metal as a material for the casting to a ladle attached to a mold to be cast by being rotated approximately 90 degrees. In the method, the height of the surface of the molten metal supplied to the ladle is measured at predetermined time intervals such that the surface of the molten metal instantaneously contacts a detection rod that has been raised in advance, and A supply speed of the molten metal is calculated from a displacement amount of the height of the detection rod before and after the measurement and the predetermined time, and an operation speed of a hot water supply device that supplies the molten metal to the ladle is adjusted based on the supply speed. Hot water supply method. "
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, one embodiment of the hot water supply method according to the present invention,
In FIG. 1, the hot water supply system includes a mold 10. The mold 10 includes an upper mold 12 and a lower mold 14, and has a cavity 16 defined therein having an inner surface corresponding to the outer shape of a product (not shown) to be cast. A ladle 18 is provided integrally with the lower mold 14, and the cavity 16 communicates with a storage portion 181 of the ladle 18. The accommodation part 181 of the ladle 18 is formed in a hemispherical concave part which is open upward. As will be described later, when the metal melt 90 supplied from the hot water supply device 20 to the storage portion 181 of the pot 18 reaches a predetermined amount, when the mold 10 is rotated by approximately 90 degrees by a driving device (not shown), the cavity 16 and is cast and the product is cast.
[0008]
The hot water supply device 20 has a main body 22 in which a molten metal 90 serving as a material of a product is stored. The float 24 is floated in the molten metal 90. The float 24 is provided integrally with a lower end of a rod 26. The upper end of the rod 26 is connected to a rod driving device 30 so that the rod 26 and the float 24 move upward (downward) by one-way operation (other direction operation) of the rod driving device 30. Has become. When the float 24 moves downward, the surface of the molten metal 90 rises in accordance with the amount of the movement, and the molten metal 90 flows from the outlet 28 formed in the main body 22 of the hot water supply device 20 into the mold 10. It is designed to be supplied into the storage section 181 of the ladle 18.
[0009]
The above-described vertical movement of the rod 26 and the float 24 is performed by the control device 40 instructing the rod driving device 30. That is, when the control device 40 sends a signal indicating the moving direction (that is, upward or downward) and the moving amount of the rod 26 to the rod driving device 30, the rod driving device 30 operates. The moving amount of the rod 26 is sent as a signal from the rod driving device 30 to the control device 40. When the moving amount reaches the specified moving amount, the control device 40 controls the rod driving device 30 to operate the rod 26. To stop. The control device 40 can also adjust the moving speed of the rod 26 by the rod driving device 30. According to the speed, the storage unit of the ladle 18 of the mold 10 per unit time is controlled. The supply amount of molten metal 90 into 181 is adjusted.
[0010]
While the molten metal 90 is supplied from the outlet 28 formed in the main body 22 of the hot water supply device 20 into the storage part 181 of the ladle 18 of the mold 10, the molten metal surface of the molten metal 90 in the storage part 181 is To rise. The height of the melt surface of the molten metal 90 can be known by a detection rod 52 which is moved up and down by a detection rod driving device 50 under the control of the control device 40. That is, when the control device 40 sends a signal indicating the moving direction (that is, upward or downward) and the moving amount of the rod detecting rod 52 to the detecting rod 50, the detecting rod driving device 50 operates. The amount of movement of the detection rod 52 is sent from the detection rod driving device 50 to the control device 40 as a signal every moment. When the detection rod 52 touches the surface of the molten metal 90, the movement is immediately stopped. 40. Then, the control device 40 immediately causes the detection rod driving device 50 to return the detection rod 52 to the original position. In addition, the control device 40 can also adjust the moving speed of the detection rod 52 by using the detection rod driving device 50. Also, as is well known, the detection rod 52 has two terminals of an open circuit, and when this terminal touches the surface of the molten metal, the circuit is closed by a terminal short circuit by the molten metal, The signal is transmitted to the control device 40, and the stop / return of the detection rod 52 is performed based on this signal.
[0011]
How the hot water supply method of the present invention is implemented by the above configuration will be specifically described.
[0012]
(1) When the hot water supply system is in a standby state, that is, before the start of hot water supply (t = T0), as shown in FIG. 2A, the detection rod 11 is in the retracted position (the position indicated by the solid line in FIG. 1). ) And is moved to the position of the height H1.
[0013]
Next, the molten metal 90 is supplied from the hot water supply device 20 to the ladle 18 of the mold 10. While this supply continues, the level of the molten metal 90 in the ladle 18 continues to rise, and at a certain time (t = T1), the level of the molten metal 90 in the ladle 18 is changed to the tip of the detection rod 11. The two terminals on the surface are contacted and the circuit is closed. A signal is sent to the controller 40 simultaneously with the closing of the circuit. Upon receiving this signal, the controller 40 shifts the detection rod 11 to the height H2. That is, in FIG. 2C, the detection rod 11 is raised from the position indicated by the broken line to the position indicated by the solid line.
[0014]
In addition, the control device 40 detects the height H1 of the detection rod 11, the internal space volume of the ladle 18 having a height equal to or less than the height H1 (stored in the control device 40 as a given value), and detection of the level of the hot water from the start of hot water supply. The actual average hot water supply speed CV1 is calculated using the time (T1-T0) until the tip surface of the bar 11 contacts. The set average hot water supply speed SV1 is stored in the control device 40. When CV1> SV1 (CV1 <SV1), the control device 40 decreases (increases) the hot water supply speed. Let it.
[0015]
The above-described rise of the detection rod 11 (from the height H1 to the height H2) is set to be higher than the hot water supply speed of the molten metal 90. As a result, contact of the tip of the detection rod 11 with the molten metal surface of the molten metal 90 is minimized, adhesion of the molten metal to the tip of the detection rod (a so-called "icicle" phenomenon) is prevented, and the detection rod is always normal. The operation is guaranteed.
[0016]
As the supply of the molten metal 90 into the ladle 18 is further continued, the level of the molten metal 90 is changed from the solid line position in FIG. 2B, that is, the broken line position in FIG. It rises to the solid line position (height H2) of (D). At this time, t = T3. Then, the surface of the molten metal 90 in the ladle 18 comes into contact with the two terminals on the distal end surface of the detection rod 11, and the circuit is closed. A signal is sent to the controller 40 simultaneously with the closing of the circuit. The control device 40 detects the height H2 of the detection rod 11, the internal space volume of the ladle 18 having a height equal to or less than the height H2 (stored in the control device 40 as a given one), and the detection rod 11 of the hot water level from the start of hot water supply. The actual average hot water supply speed CV2 is calculated using the time (T3−T0) until the contact with the front end surface of the water heater. The set average hot water supply speed SV2 is stored in the control device 40. When CV2> SV2 (CV2 <SV2), the control device 40 decreases (increases) the hot water supply speed. Let it.
[0017]
Then, when the surface of the molten metal 90 in the ladle 18 reaches a predetermined height (when the molten metal 90 in the ladle 18 reaches a predetermined amount), the hot water supply is stopped.
[0018]
In addition, by repeating the above-described steps (2) to (4), the surface of the molten metal 90 in the ladle 18 can be set to a certain degree in the pattern of the hot water supply, for example, in a mode as shown in FIG. That is, in the hot water supply mode shown in FIG. 3, hot water is supplied at the beginning of hot water supply to prevent air entrapment and a decrease in temperature. Thereafter, the hot water supply rate is increased to increase the amount of hot water supply per unit time in order to shorten the hot water supply time and prevent the temperature from decreasing, and before the hot water supply is completed, the hot water supply rate is reduced in order to improve the accuracy of the hot water supply.
[0019]
The hot water supply from the hot water supply device 20 may be replaced by a pump instead of the extrusion of the melt from the float. In this case, the discharge amount of the pump needs to be variable.
[0020]
【The invention's effect】
According to the present invention, since the above-mentioned problem can be solved, the pattern of hot water supply can be arbitrarily set to some extent, so that productivity can be improved and cost can be reduced. Further, the so-called "icicle" phenomenon can be avoided, and the accuracy and reliability of the device can be ensured.
[Brief description of the drawings]
FIG. 1 is a block diagram of an apparatus for implementing a hot water supply method according to the present invention.
FIG. 2 is a diagram showing changes over time in the hot water supply method according to the present invention.
FIG. 3 is a graph showing changes in various factors in the hot water supply method according to the present invention.
FIG. 4 is a graph showing a change in hot water supply speed when another hot water supply method according to the present invention is performed.
[Explanation of symbols]
Reference Signs List 10 Mold 11 Detection rod 18 Ladle 20 Hot water supply device

Claims (1)

In a hot water supply method for supplying a molten metal of a metal as a material for the casting to a ladle attached to a mold to be cast by being rotated by about 90 degrees, the molten metal supplied to the ladle is provided. The height of the surface is measured every predetermined time so that the molten metal surface instantaneously comes into contact with the detection rod that has been raised in advance, and the displacement amount of the height of the detection rod before and after the measurement and the A hot water supply method, comprising: calculating a supply speed of the molten metal from a predetermined time; and adjusting an operation speed of a hot water supply device that supplies the molten metal to a ladle based on the supply speed.

Images