JPS63223488A - Method and device for controlling temperature of heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a heating device for heating a material to be heated, and in particular,
The present invention relates to a temperature control method and a temperature control device for controlling the temperature of the heating device.

Prior art The temperature control method for a heating device that heats a material to be heated generally involves using a thermocouple to control the ambient temperature within the heating device.

Current supplied to the heat source of the heating device, i.e., the heater, burner, etc., so that the ambient temperature matches the preset temperature as detected by a resistance temperature detector.

Normally, the amount of combustion etc. is controlled by feedbank.

Problems to be Solved by the Invention However, since such conventional temperature control methods do not directly detect the temperature of the material to be heated, it is difficult to accurately heat the material to a predetermined heating temperature. There were cases where this was not possible.

In other words, it is effective when the heating time is long and the temperature of the material to be heated and the ambient temperature inside the heating device are the same or there is a certain relationship between them, but direct current heating or induction heating is effective. When there is no direct relationship between the temperature of the material to be heated and the ambient temperature, or when there is a large temperature difference due to high-speed heating, the actual temperature of the material to be heated should match the predetermined heating temperature. It is difficult to control the temperature of the heating device to achieve this.

On the other hand, instead of detecting the ambient temperature inside the heating device, it may be possible to directly detect the actual temperature of the material to be heated, but since the inside of the heating device is affected by the furnace wall, burner frame, etc. It is not possible to detect the temperature of the heated material with high accuracy.

Means for Solving the Problems The present invention has been made to solve the above problems, and its gist is that the material to be heated, which is supplied at regular time intervals, is heated for a given time. A method for controlling the temperature of a heating device that is subsequently discharged, the method comprising: fa) a temperature measuring step of measuring the actual temperature of the material to be heated that is intermittently discharged from the heating device; and a control step of controlling the temperature of the heating device so that the temperature of the heating device matches a predetermined heating temperature.

Further, such a temperature control method includes, for example, (X) a radiation thermometer that measures the actual temperature of the material to be heated that is intermittently discharged from the heating device and outputs a temperature signal representing the actual temperature; , [yl] is suitably carried out by a temperature control device including a control means for controlling the temperature of the heating device so that the actual temperature of the heated material represented by the temperature signal matches a predetermined heating temperature. .

Function and Effect of the Invention Namely, the present invention measures the actual temperature of the heated material discharged after being heated by the heating device for a certain period of time, and the actual temperature matches the predetermined heating temperature. In this way, the temperature of the heating device can be controlled in such a way that it can be used in cases where the ambient temperature inside the heating device and the temperature of the material to be heated are not directly related or where there is a large temperature difference. It also becomes possible to heat the material to be heated to a predetermined heating temperature with high accuracy. In particular, since the present invention measures the temperature of the material to be heated discharged from the heating device, the accuracy of temperature measurement is higher than that in the case where the temperature of the material to be heated is measured within the heating device. It is possible to control the temperature.

Furthermore, since the temperature control device measures the temperature of the material to be heated using a radiation thermometer, it is possible to measure the temperature of the high-temperature material to be heated in a short time with high precision, and the temperature of the material to be heated can be can be quickly sent to subsequent processes.

Note that the control means of such a temperature control device includes, for example,
a modulator that holds the temperature signal intermittently output from the radiation thermometer until the next temperature signal is output and converts it into a continuous signal; Although the device is configured to include a temperature controller for controlling the temperature of the device, it is also possible to use a microcomputer with the same functions.

EXAMPLE Hereinafter, an example of the present invention will be described in detail based on the drawings.

In FIG. 1, 10 is a combustion type heating device, and a heating furnace 12. Burner 14. It is equipped with a fuel supply facility 16° and an air supply facility 8. The heating furnace I2 is a rotary furnace that accommodates and heats a large number of annular materials to be heated 26 therein. Heating material 2
Each time 6 is supplied, the heated material 26 heated for a certain period of time is discharged one by one. Furthermore, the burner 14 mixes and burns heavy oil and air supplied from the fuel supply equipment 16 and the air supply equipment 18 through control valves 20 and 22, respectively, to heat the material to be heated 26 in the heating furnace 12. Heat at high speed. The temperature inside the heating furnace 12, that is, the combustion amount of the burner 14, is controlled by changing the opening degree of the control valve 20.22. The temperature is automatically adjusted by the temperature control bag N24.

The temperature control device 24 includes a radiation thermometer 28 that measures the temperature of the heated material 26 discharged from the heating furnace 12.
．． Modulator 30. It consists of a temperature controller 32° and a control motor 34. The radiation thermometer 28 is placed at a preset temperature measuring position near the discharge position of the material to be heated 26, and measures the actual temperature of the material to be heated 26 based on the thermal radiation energy radiated from the material to be heated 26. and transmits a temperature signal ST representing the actual temperature to a modulator 30.
supply to The graph of the thermometer output shown at the top of FIG.
The output signal is intermittently raised each time it passes the temperature measuring position, and the value at that time corresponds to the temperature signal ST representing the actual temperature of each heated material 26. The material to be heated 26 discharged from the heating furnace 12 is passed through the temperature measuring position by a conveyor or the like, and is further carried out to a post-process where hot forging or the like is performed.

The modulator 30 uses the heated material 2 discharged from the heating furnace 12.
The temperature signal ST intermittently supplied from the radiation thermometer 28 is converted into a continuous signal STC and output to the temperature controller 32 each time the thermometer 6 passes the temperature measuring position. When one temperature signal ST, is supplied, the next temperature signal STfi,.

The temperature signal ST is held and output until the temperature signal ST is supplied. In this case, the temperature signal ST fluctuates as one material to be heated 26 passes through the temperature measuring position, but the modulator 30 detects the maximum temperature of the material to be heated 26,
Continuous signal STC based on average temperature, minimum temperature, etc.
Output. The graph of the modulator output in FIG.
This shows the output signal output from 0, and the portion shown after time t3 corresponds to the continuous signal STC. In this embodiment, the materials to be heated 26 are discharged one by one from the heating furnace 12, but when a plurality of materials to be heated 26 are discharged at the same time, one of the materials to be heated is discharged from the heating furnace 12. Continuous signal S based on the temperature of heating material 26
TC may be output, or a continuous signal STC may be output based on the maximum temperature, average temperature, minimum temperature, etc. of the plurality of heated materials 26 discharged at the same time.

The modulator 30 is equipped with various functions in addition to converting the temperature signal ST into a continuous signal STC, and its front panel 35 has a display as shown in FIG. Vessel 36. Upper limit temperature setter 38. Lower limit temperature setting device 40. Preheating temperature setter 42. Response speed setter 44. Push button 46 for switching output mode to automatic or manual
and 48, pushbuttons 50 and 52 for raising or lowering the output signal when in manual mode. A power switch 54 is provided. The display 36 displays the temperature represented by the output signal of the modulator 30 regardless of the automatic mode or manual mode. For example, when the continuous signal STC is output in the automatic mode, the temperature represented by the continuous signal STC is displayed. The actual temperature of the heated material 26 is displayed. The upper limit temperature setter 38 and the lower limit temperature setter 40 set the upper limit temperature TLl and the lower limit temperature TL of the temperature range in which the temperature signal ST supplied from the radiation thermometer 28 is to be converted into a continuous signal STC.
The temperature signal ST that does not fall within this temperature range is removed as noise before being converted into a continuous signal STC.

For example, the two temperature signals ST' shown in the graph showing the thermometer output in FIG. However, since none of them are within the above temperature range, they are removed as noise.
The graph of the modulator output shown below, ie the continuous signal STC, represents the temperature signal ST which represents the actual temperature of the heated material 26 without being influenced by those temperature signals ST'.
The output is based only on The upper limit temperature Tu and the lower limit temperature TL are set in advance based on the target temperature TM set in the temperature controller 32.

The preheating temperature setter 42 is for setting the preheating temperature of the heating furnace 12, and until the temperature signal ST is supplied in automatic mode, an output signal representing this preheating temperature is output to the temperature controller 32. be done. The part of the graph of the modulator output in FIG. 2 before time t3 is an output signal representing this preheating temperature, and the temperature in the heating furnace 12 is the target temperature T8
The temperature is set to be about the same as or slightly higher than . The response speed setter 44 is for setting the rate of change when changing the value of the continuous signal STC in accordance with the newly supplied temperature signal ST, and sets the rate of change based on a predetermined rate of change. It can be increased or decreased.

The push buttons 46 and 48 for switching the output mode are used, for example, when igniting or extinguishing the burner 14.
Alternatively, when the temperature signal ST is not supplied from the radiation thermometer 28, such as when adjusting the preheating temperature, the output signal can be manually operated, and the manual push button 48 is pressed. When the pushbuttons 50, 52 are pressed, the output signal is raised or lowered.

Further, when the automatic push button 46 is pressed, an output signal representing the preheating temperature set by the preheating temperature setting device 42 is output, and when the temperature signal ST is supplied from the radiation thermometer 28, the output signal is continuously output. A signal STC is output.

Returning to FIG. 1, the temperature controller 32 is supplied with an output signal including the continuous signal STC from the modulator 30, so that the temperature controller 32 can adjust the temperature represented by the modulator output signal and the preset target temperature TM. In other words, the temperature represented by the modulator output signal and the target temperature TM are compared so that their deviations are eliminated.
In order to increase or decrease the combustion amount of the burner 14 so that it matches, a contact signal SS for operating the control motor 34 is output. That is, as is clear from the graph showing the modulator output and temperature controller contact output in FIG. 2, when the temperature represented by the modulator output signal (continuous signal 5TC) is higher than the target temperature T, the control Contact signal SS in the direction of closing valve 20.22
is output for a time corresponding to the deviation, and the temperature represented by the modulator output signal is the target temperature T. If the deviation is lower than the deviation, a contact signal SS in the direction of opening the control valves 20, 22 is output for a time corresponding to the deviation.

The target temperature T, 4 is the heating temperature of the material to be heated 26, and is set in advance by a setting device (not shown).

The control motor 34 to which the contact signal SS is supplied is
A crank arm 56 is attached to the output shaft, and a link 58 . It is connected to the opening/closing shafts of the control valves 20, 22 via levers 60, 62. Then, by rotating the crank arm 56 in accordance with the contact signal SS supplied from the temperature controller 32, the opening/closing shafts of the control valves 20 and 22 are rotated by an angle proportional to the rotation angle of the crank arm 56. Fuel supply equipment 16. The flow rates of heavy oil and air supplied from the air supply facility 18 are controlled respectively.

Further, a position signal Sx representing the rotation angle of the crank arm 56 is fed back from the control motor 34 to the temperature controller 32. Second
The graph of the control motor output in the figure shows the angle change of the crank arm 56.

Next, the operation of the temperature control device 24 configured as above will be explained.

First, the modulator 30 is placed in manual mode by pushbutton 48, and the burner 14 is fired by manually manipulating the modulator output signal by pushbuttons 50,52. Thereafter, by setting the automatic mode using the push button 46, the temperature inside the heating furnace 12 is raised to a predetermined preheating temperature, and supply of the material to be heated 26 into the heating furnace 12 is started. Time t1 in Figure 2
is the time at this time.

The materials to be heated 26 are supplied into the heating furnace 12 at predetermined fixed time intervals, and when the number reaches the capacity of the heating furnace 12, the materials to be heated 26 that have been supplied earlier and heated for a certain period of time are The material 26 is a new heated material 26 in the heating furnace 12.
The heating furnace 12 is discharged each time it is fed into the furnace 12 .

At time t2 in FIG. 2, the first material to be heated 26 is in the heating furnace 1.
This is the time when it was ejected from 2.

When the heated material 26 discharged from the heating furnace 12 passes through the temperature measurement position, the actual temperature of the heated material 26 is measured by the radiation thermometer 28, and a temperature signal ST representing the temperature is sent to the modulator. 30. Time t3 in FIG. 2 is the time at this time, and this process is the temperature measurement process.

The modulator 30 converts the temperature signal ST into a continuous signal STC and outputs it to the temperature controller 32.
A contact signal SS is output based on the deviation between the actual temperature of the heated material 26 represented by the temperature signal STC and the target temperature T. Then, by operating the control motor 34 in accordance with this contact signal SS, the opening degree of the control valve 20.22 is adjusted, and the combustion amount of the burner 14, that is, the temperature in the heating furnace 12 is adjusted to the actual temperature of the material to be heated 26. The temperature is controlled to match the target temperature TM. This process is a control process, and the modulator 3 that executes this process
0. Temperature controller 32. and a control motor 34 constitute a control means.

Thereafter, each time one material to be heated 26 is discharged from the heating furnace 12, the actual temperature of the material to be heated 26 is adjusted to match the target temperature TM based on the temperature signal ST output from the radiation thermometer 28. The temperature within the heating furnace 12 is continuously controlled. The graph of the estimated furnace temperature value shown at the bottom of FIG. 2 shows the estimated value of the temperature inside the heating furnace 12 controlled in this way.

When the heating device 10 finishes heating the material 26 to be heated, the output mode of the modulator 30 is set to manual mode, and the push buttons 50, 52 are pressed to stop the combustion of the burner 14.

In this way, the temperature control device 24 of this embodiment can control the heating furnace 1.
The temperature inside the heating furnace 12 is controlled so that the actual temperature of the material to be heated 26 discharged from the heating furnace 12 is measured, and the actual temperature matches the predetermined heating temperature, that is, the target temperature T. Therefore, even if there is a large temperature difference between the ambient temperature in the heating furnace 12 and the actual temperature of the material to be heated 26 during high-speed heating, the material to be heated can be heated to a predetermined heating temperature with high accuracy. It is.

Furthermore, since the temperature control device 24 measures the temperature of the material to be heated 26 discharged from the heating furnace 12, compared to the case where the temperature of the material to be heated 26 is measured inside the heating furnace 12, Since the temperature measurement accuracy is high and the radiation thermometer 28 is used for temperature measurement, the temperature of the high-temperature material to be heated 26 can be measured with high precision in a short time, and the temperature inside the heating furnace 12tl can be measured accurately. Control is extremely good, and the material to be heated 26 can be quickly sent to the subsequent process.

Furthermore, the modulator 30 of the present embodiment removes as noise any part of the temperature signal ST supplied from the radiation thermometer 28 that does not fall within a certain temperature range defined by the upper limit temperature Tu and the lower limit temperature TL. Because of this, the heating furnace 1 is damaged by scales etc. that have fallen from the material to be heated
Temperature control within 2 is not impaired.

Next, another embodiment of the present invention will be described. In the following embodiments, parts common to those in the above embodiments are designated by the same reference numerals, and explanations thereof will be omitted.

The embodiment of FIG. 4 is similar to the modulator 30 in the first embodiment.
The temperature controller 32 is configured by a so-called microcomputer, and the temperature signal ST output from the radiation thermometer 28 is supplied to the CPU 66 via an A/D converter 64. A RAM 68 and a ROM 70 are connected to the CPU 66 via a data bus line, and the CPU 66 performs signal processing according to a program stored in advance in the ROM 70 while utilizing the primary storage function of the RAM 6 B. A signal SS is output to the control motor 34. Further, the position signal SX is supplied from the control motor 34 to the CPU 66 via the A/D converter 74, and the target temperature T, etc. is supplied to the setting device 7.
6.

The temperature control device 78 is controlled according to the flowchart shown in FIG. 5, for example. That is, first, in step Sl, it is determined whether or not the temperature signal ST has been manually input, and when input, in step S2, the temperature deviation between the actual temperature of the material to be heated 26 represented by the temperature signal ST and the target temperature TM is calculated. . Step S3
In the above, based on the temperature deviation, the material to be heated 26
burner 1 so that the actual temperature of burner 1 matches the target temperature T4.
The operating amount for controlling the combustion amount of the control motor 46, specifically the operating amount of the control motor 34, is determined, and in the subsequent step S4, a contact signal SS representing the operating amount is outputted from the output interface 72. Thereby, similarly to the first embodiment, the combustion amount of the burner 14, that is, the temperature inside the heating furnace 12, is controlled so that the actual temperature of the material to be heated 26 matches the target temperature T.

In this embodiment, the control means includes a CPU 66, a RAM 68°, and a ROM 70.

Further, the flowchart shown in FIG. 5 is simply for explaining the operation of controlling the control motor 34 based on the temperature signal ST, and although detailed explanation is omitted, this temperature control device 78 also As in the first embodiment, temperature signals ST outside a certain temperature range are removed as noise in advance, and the combustion amount of the burner 14 can be adjusted manually.

Although the embodiments of the present invention have been described above in detail with reference to the drawings, the present invention can also be implemented in other embodiments.

For example, in the embodiment described above, the temperature control device 24.78 of the heating device 10 heated by the burner 14 was explained, but it goes without saying that a heater can be used in place of the burner 14, and other types of heating such as direct current heating, induction heating, etc. The present invention can be similarly applied to a temperature control method and a temperature control device for a heating device.

Furthermore, in the embodiment described above, the temperature of all the materials to be heated 26 discharged from the heating furnace 12 is measured to control the temperature inside the heating furnace 12. Depending on the situation, the temperature of the material to be heated 26 may be measured at every other wire, or every two wires, or the like.

Further, in the embodiment described above, the temperature is measured while the material to be heated 26 passes through the temperature measurement position, but the material to be heated 26 is temporarily stopped at the temperature measurement position in order to measure the temperature. You can also.

Furthermore, in the embodiment described above, the temperature signal ST outputted from the radiation thermometer 28 that is outside a predetermined temperature range is removed as noise, but the ejection time of the material to be heated 26 is Other noise removal means may also be provided, such as noise removal based on spacing. Note that, of course, the effects of the present invention can be obtained even without the function of removing such noise or the function of manually adjusting the combustion amount of the burner 14.

Although other examples are not given, the present invention can be implemented with various modifications and improvements based on the knowledge of those skilled in the art without departing from the spirit thereof.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram illustrating a heating device equipped with a temperature control device, which is an embodiment of the present invention. FIG. 2 is a time chart illustrating the operation of the device shown in FIG. FIG. 3 is a diagram showing the front panel of the modulator in the device of FIG. 1. FIG. 4 is a block diagram illustrating another embodiment of the present invention. FIG. 5 is a flowchart for explaining the operation of the embodiment shown in FIG. 10: Heating device 24.18: Temperature control device 26:
Heated material 28: Radiation thermometer 30: Modulator
32: Temperature controller 34: Control morph 66: CPU 68: RAM70: ROM 5T: Temperature signal STC: Continuous signal T, 4: Target temperature (heating temperature)

Claims (3)

[Claims] (1) A method for controlling the temperature of a heating device that heats a material to be heated that is supplied at regular time intervals for a certain period of time and then discharges the material to be heated, the method comprising: A heating device comprising: a temperature measurement step of measuring an actual temperature; and a control step of controlling the temperature of the heating device so that the measured actual temperature matches a predetermined heating temperature. temperature control method. (2) A device for controlling the temperature of a heating device that heats the material to be heated that is supplied at regular time intervals for a certain period of time and then discharges the material to be heated, which is intermittently discharged from the heating device. a radiation thermometer that measures an actual temperature and outputs a temperature signal representing the actual temperature; and a radiation thermometer that measures the actual temperature and outputs a temperature signal representing the actual temperature; 1. A temperature control device for a heating device, comprising: control means for controlling the temperature of the device. (3) The control means includes a modulator that holds the temperature signal that is intermittently output from the radiation thermometer and converts it into a continuous signal until the next temperature signal is output; 3. The temperature control device for a heating device according to claim 2, further comprising a temperature controller that controls the temperature of the heating device based on a continuous signal.