JPS6319254B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a thin plate manufacturing apparatus for producing a thin plate by pouring molten metal from a pouring nozzle onto the surface of a rotating drum, cooling and solidifying the metal on the surface of the rotating drum.

[Conventional technology]

A conventional thin plate manufacturing apparatus is constructed as shown in FIGS. 2A and 2B. That is, the drum 1 is fixed to a shaft 3 rotatably supported by a bearing 2,
A furnace 4 is arranged above the drum 1.
A slit-shaped opening 5A of a pouring nozzle 5 provided at the lower end of the furnace 4 is arranged opposite to the upper surface of the drum 1 at a predetermined interval. A coil-shaped heater 6 is wound around the outer periphery of the furnace 4 and heats the metal in the furnace 4 to form a molten metal 7.

The molten metal 7 in the furnace 4 is poured out onto the surface of the drum 1 from the opening 5A of the pouring nozzle 5 on the surface of the drum 1 by pressurized fluid supplied from the pump 8 and regulated by the valve 9. Cooled and solidified to form thin plate 1
It becomes 0.

[Problem that the invention seeks to solve]

Here, if it is necessary to interrupt the heating and melting of the metal inside the furnace 4 or the production of the thin plate 10, it is necessary to prevent the molten metal 7 from leaking out from the pouring nozzle 5 due to gravity. In such a case, in the conventional thin plate manufacturing apparatus, the pump 8 that supplies pressurized fluid to the furnace 4 is stopped, and
A vacuum pump 9A is connected to the furnace 4 to bring the cavity 4A into a negative pressure state, or a shielding plate for leakage prevention is provided at the tip of the pouring nozzle 5.

However, in the conventional leakage prevention method described above,
It is difficult to completely prevent leakage from the spout nozzle 5, and the opening 5A may become partially clogged 13. In other words, the occurrence of 13 is
This may impede normal ejection of the molten metal 7 over the entire length in the width direction of the opening 5A of the pouring nozzle 5, and the obtained thin plate 10 may be divided in the width direction.

Therefore, for example, as described in JP-A-55-120454, a method was proposed in which the pouring nozzle is formed upward and the molten metal is supplied from below the drum.

However, when the nozzle is directed upward, a new problem arises that is different from that of a downward nozzle. That is,
When the spout nozzle faces upward, unless the gap between the tip of the spout nozzle and the rotating drum is accurately maintained at a predetermined value, it will be difficult to produce a uniform thin plate due to the force of gravity acting on the molten metal. Other factors related to the thickness of the thin plate include the furnace pressure, the peripheral speed of the rotating drum, and the temperature of the molten metal. There was a lack of consideration.

An object of the present invention is to provide a thin plate manufacturing apparatus that eliminates the influence of variations in factors related to thickness when an upward nozzle is employed and can produce a uniform thin plate.

[Means for solving problems]

In order to achieve the above object, the present invention pours molten metal contained in a furnace from an upward pouring nozzle onto the surface of a rotating drum disposed above the furnace, cools and solidifies it on the surface of the rotating drum, and manufactures a thin plate. A gap detection sensor for detecting the gap size between the tip of the pouring nozzle and the surface of the rotating drum for thin plate manufacturing equipment;
The output of this gap detection sensor is compared with the appropriate value of the set gap size, and if there is a deviation, the spout nozzle is moved up and down with respect to the rotating drum surface to eliminate the difference and maintain the gap at the appropriate value. A mechanism that detects the furnace pressure, a furnace pressure detection sensor that detects the furnace pressure, and a furnace pressure detection sensor that compares the output of this furnace pressure detection sensor with the set appropriate value of the furnace pressure, and if there is a deviation, controls the furnace pressure to eliminate the difference. It is proposed that the system be equipped with a mechanism.

[Effect]

According to the above configuration of the present invention, it is possible to accurately control the furnace internal pressure, which is a direct factor of the pouring amount, and also to reduce the gap between the pouring nozzle and the rotating drum, which causes thickness unevenness especially when it is large. By adding a precise control mechanism, the thickness of the thin plate can be kept uniform.

〔Example〕

Next, an embodiment of the present invention will be described with reference to FIG. FIG. 1 is an overall configuration diagram showing, partially in cross section, an embodiment of a thin plate manufacturing apparatus according to the present invention.

In FIG. 1, a furnace 11 has an upper opening into which metal is introduced with a cover 12, a heater coil 13 is wound around the outer periphery, and a molten metal 14 is accommodated. A pouring pipe 15 extending from the bottom side to above the cover 12 is arranged in the center of the furnace 11 . A spout nozzle 16 whose diameter gradually decreases is arranged at the upper end of the spout pipe 15 and is fixed to the cover 12 by a presser foot 17. Above the pouring nozzle 16 is a drive motor 18.
The lower outer circumferential surfaces of the drums 20 fixed to the rotating shaft 19 are arranged to face each other.

The metal put into the furnace 11 is heated by the heater coil 1
3 becomes molten metal 14 by energizing, and the furnace pressure 2
1 rises inside the spouting pipe 15,
It is poured from the pouring nozzle 16 onto the surface of the drum 20, cooled and solidified on the surface of the drum 20, and becomes the thin plate 2.
It becomes 2.

A method of controlling factors related to the thickness accuracy of the thin plate 22 manufactured in this manner, such as the furnace internal pressure 21 and the gap between the pouring nozzle 16 and the drum 20, will be explained.

Among the four factors of furnace pressure 21, circumferential speed of drum 20, temperature of molten metal, and gap between pouring nozzle 16 and drum 20, if the remaining three factors are fixed and each factor is adjusted independently, , the thickness of the thin plate can be controlled with the necessary precision. However, in general, the responsiveness of plate thickness accuracy control by adjusting the furnace pressure 21 is better than when using other factors, so in this example, the other three factors are maintained at predetermined values. By quickly adjusting the furnace internal pressure 21, the plate thickness can be controlled with high precision.

The furnace internal pressure 21 is applied to the drum 2 so as to be able to contact the thin plate 22.
A thickness detection sensor (differential transformer) 24 detects the thickness of the thin plate 22 based on the amount of movement of the contact roller 23 (the amount of movement of the drum 20 in the radial direction, that is, the amount of movement in the plate thickness direction). , cover 12
A pressure sensor (pressure head) 25 installed inside the furnace to detect the furnace internal pressure 21, and a pressure setting device 26 to set the appropriate value for the furnace internal pressure. controlled by. The pressure control device 27 is a control panel including a calculator such as a microcomputer, and the pressure setting device 26 is a numerical input means such as a potentiometer for analog control and a numeric keypad for digital control. Once the target value (command value or optimum value) is set, this pressure setting device 26 maintains that value, but when the operating conditions change, the operator resets the target value.

The amount spouted from the pouring nozzle 16 is determined by the furnace pressure P, which determines the thickness of the thin plate 22. Plate thickness h
The relationship between and the furnace internal pressure P is h=C√. However, if the shape of the nozzle changes or the viscosity of the molten metal changes, the constant C changes. When the constant C changes from the initial design value a, the relationship between P and h changes as shown in FIG. From the pressure setting device 26,
A pressure P ₀ corresponding to the target plate thickness h ₀ is given, and the furnace pressure is controlled to be P ₀ . However, if the viscosity of the molten metal changes during operation, the relationship between h and P changes as shown by a broken line or a chain line. Then, the plate thickness is
Therefore, in the present invention, the value _of C is calculated periodically or as needed based on the signal from the thickness detection sensor 24 _and the signal from the furnace pressure detection sensor 25, and this The value is the initially set value a
If there is a change from the set value, the set value
Add correction to P ₀ . In other words, when C is the value shown by the dashed-dotted line, if feedback control is performed using the set value P ₀ ' as the target value, the plate thickness becomes h ₀ . In this way, the value of C is calculated, the target value of the furnace pressure is corrected, and the desired plate thickness h ₀ can be obtained even if the conditions change. This calculation and correction of the target value are performed inside the pressure control device 27.

Based on the control amount of the pressure control device 27, a hydraulic cylinder 31 is actuated via a servo valve 30 by a hydraulic source consisting of a hydraulic pump 28 and a tank 29. The hydraulic cylinder 31 is connected to the piston rod 3
2, a pneumatic cylinder 3 disposed on a pedestal 33
The volume of the cylinder chamber 34A of No. 4 is changed. Since the atmospheric pressure cylinder 34 communicates with the upper space of the furnace 11, changes in the cylinder chamber 34A immediately control the furnace internal pressure 21. A rubber spring 36 is interposed between the piston rod 32 and the frame 35 in the direction of movement of the piston rod 32 to improve the responsiveness of this control system. On the other hand, detection signals from a pressure cylinder position detection sensor (differential transformer) 37 and a furnace pressure detection sensor 25 connected to the piston rod 32 are transmitted to a valve 40 connected to a pressure pump 38 and a vacuum pump 39, and the melting In response to an increase in the pouring head and a decrease in the furnace pressure 21 due to the pouring of the metal 14 from the pouring nozzle 16, pressure fluid is replenished into the space of the furnace 11, thereby making it possible to control the furnace pressure 21. Note that a throttle 41 is provided in the piping system of the valve 40, and from the operation of the pneumatic cylinder 34,
The influence on the valve 40 is reduced.

The circumferential speed of the drum 20 is determined by transmitting each output value of the thickness detection sensor 24, speed detection sensor (optical encoder) 42, and speed setting device 43 to the speed control device 44, and controlling the drive motor based on the control command from the speed control device 44. It is controlled by adjusting the rotation speed of 18.

The temperature of the molten metal 14 in the furnace 11 is determined by transmitting the output values of a temperature detection sensor (infrared thermometer) 45 and a temperature setting device 46 to a temperature control device 47, and controlling the coil power supply unit based on a control command from the temperature control device 47. 48 and by adjusting the current value of the heater coil 13. In addition, in controlling the temperature of the molten metal 14 as well, the output value of the thickness detection sensor 24 is transmitted to the temperature control device 47, and based on the detected thickness value of the thin plate 22,
The temperature control may also be carried out directly in relation to the plate pressure of the thin plate 22.

The gap between the pouring nozzle 16 and the drum 20 is determined by adjusting the output values of a gap detection sensor (optical displacement sensor) 49 and a gap setting device (input means such as a potentiometer or numeric keypad) 50 using a gap control device (microcomputer, etc.). control panel (including a computer) 51, the hydraulic cylinder 52 is operated according to the control command of the gap control device 51, and the furnace 11
It is controlled by moving the base 53 supporting it up and down.

Furthermore, a temperature detection sensor (infrared thermometer) 54 is disposed at an arbitrary position corresponding to the outer peripheral surface of the drum 20, and based on the detected value of the temperature detection sensor 54, cooling air is supplied from the outside of the drum 20 by a blower fan (not shown). etc., to control the temperature of the drum 20. By controlling the temperature of the drum 20, the material properties of the thin plate 22 can be adjusted.

The thin plate 22 whose thickness accuracy and material properties have been adjusted in this manner is wound onto a coil by the following winding means. That is, bracket 55
An L-shaped swinging arm 56 is supported on the swinging arm, and a winding drum 58 is fixed to a support shaft 57 provided at one end of the swinging arm. The winding drum 58 is disposed corresponding to the outer peripheral surface of the drum 20, is rotated by a winding motor 59, and winds up the thin plate 22 under the action of vacuum suction force or electromagnetic suction force. The other end of the swing arm 56 is connected to the tip of a piston rod of a pressing cylinder 61 supported by a trunnion on a bracket 60. The pressing cylinder 61 pushes the winding drum 58 toward the drum 20 side, and as the thin plate 22 is wound on the winding drum 58 and the winding diameter increases, the pressing cylinder 61 moves the piston rod backward so that the winding drum 58 is drum 20
A swinging arm 56 is held swingably in a direction away from.

The winding motor 59 includes an acceleration/deceleration compensator 62 that adjusts the rotation speed of the winding drum 58 according to acceleration/deceleration of the drum 20, a torque setting device 63, and a winding motor 5.
The torque is controlled to an appropriate value by the control command of the torque control device 65 to which each detection value of the current detection sensor 64 that detects the current value of 9 is transmitted, and the tension acting on the thin plate 22 during winding is kept constant. keep.

〔Effect of the invention〕

According to the present invention, it is possible to accurately control the furnace internal pressure, which directly determines the pouring amount, and it is also possible to accurately control the gap between the pouring nozzle and the rotating drum, which causes variations in thickness, resulting in uniform thickness. A thin plate is obtained.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing a partial cross section of an embodiment of a thin plate manufacturing apparatus according to the present invention, FIG. 2A is a front view showing main parts of a conventional thin plate manufacturing apparatus, and FIG. 2B is a side view thereof. , FIG. 3 is a diagram showing the relationship between plate thickness h and furnace pressure P. 11... Furnace, 13... Heater coil, 14...
Molten metal, 16... Pouring nozzle, 18... Drum drive motor, 20... Rotating drum, 21... Furnace pressure, 22... Thin plate, 23... Contact roller, 24...
...thickness detection sensor, 25...furnace pressure detection sensor,
27...Pressure control device, 28...Hydraulic pump, 3
1... Hydraulic cylinder, 34... Air pressure cylinder, 3
8... Pressure pump, 39... Vacuum pump, 42...
... Motor speed detection sensor, 47 ... Temperature control device, 48 ... Coil power supply, 49 ... Gap detection sensor, 50 ... Gap setting device, 51 ... Gap control device, 52 ... Hydraulic cylinder, 53 ...
Base, 58... Winding drum, 59... Winding motor, 65... Torque control device.

Claims (1)

[Scope of Claims] 1. A thin plate manufacturing apparatus that produces a thin plate by pouring molten metal contained in a furnace from an upward pouring nozzle onto the surface of a rotating drum disposed above the metal, cooling and solidifying it on the surface of the rotating drum, A gap detection sensor detects the gap size between the dispensing nozzle tip and the surface of the rotating drum, and the output of the gap detection sensor is compared with the set appropriate value of the gap size, and if there is a deviation, the above-mentioned gap detection sensor is used to eliminate the difference. a mechanism for moving the pouring nozzle up and down with respect to the rotating drum surface to maintain the gap at an appropriate value; a furnace pressure detection sensor for detecting the furnace pressure; and a furnace in which the output of the furnace pressure detection sensor is set. 1. A thin plate manufacturing apparatus comprising a mechanism for comparing the internal pressure with an appropriate value and controlling the furnace internal pressure so as to eliminate the difference if there is a deviation.