JPS6122756B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an internal pressure control device for maintaining a constant internal pressure of, for example, a heating furnace.

The following description will be made using a heating furnace as an example.

Conventionally, this type of control device has been shown in FIGS. 1 to 3. In the figure, 1 is a heating furnace, 2 is a charging door for charging materials into this heating furnace 1, 3 is a flue, and 4 is a flue installed in this flue 3 to keep the pressure inside the furnace constant. damper; 5 is a detector for measuring the furnace internal pressure; 6 is a converter for inputting the value measured by this detector 5 to a control device 10 that controls the furnace internal pressure to be constant; 7 is a flue damper 4; 11 is a setting device for setting the furnace internal pressure.

Next, the operation of the conventional internal pressure control device configured as described above will be explained. First, the set value SV of the furnace internal pressure is set by the setting device 11, and this set value SV is matched with the measured value PV of the furnace internal pressure obtained via the converter 6, and the deviation amount is controlled by PI in the control device 10. , the output value MV of the furnace pressure that outputs the opening degree of the flue damper 4 is determined.

As a result, when the furnace pressure changes due to some kind of disturbance, the measured value PV of the furnace pressure changes and the set value SV of the furnace pressure changes.
The output value MV, which controls the opening degree of the flue damper 4, was controlled by the change in the deviation amount of the measured value PV of the furnace internal pressure.

Conventional furnace internal pressure control devices are configured as described above, and after the furnace internal pressure changes, PI control is performed to suppress the amount of change (deviation amount).
Since the control is performed after fluctuations in the furnace internal pressure occur due to the opening and closing of the charging door 2, there is a time delay in the control and accurate control cannot be expected.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and includes a first calculation device that outputs an output at a predetermined slope based on an opening/closing operation notice signal immediately before the loading door is opened/closed. , a second calculation device that detects the movement of the charging door, calculates and outputs the opening degree thereof, and an adjustment device that adjusts the opening degree of the damper based on the outputs of the first and second calculation devices. It is an object of the present invention to provide an internal pressure control device that can always maintain a constant furnace pressure by adjusting the opening degree of a damper before the furnace internal pressure changes.

Hereinafter, one embodiment of the present invention will be described based on FIGS. 4 and 5.

In the figure, a heating furnace 1, a charging door 2, a flue 3, a flue damper 4, a detector 5, a converter 6, an electrohydraulic operating device 7, and a setting device 11 are the conventional ones shown in FIGS. 1 to 4. Since it is similar to , the explanation will be omitted. 8 is a pulse transmitter that detects and outputs the opening degree of the charging door 2; 9 is a warning transmitter that outputs a warning signal for the opening/closing operation of the charging door 2 (for example, 5 seconds before the start of operation); This is a material detector that is installed just before 2 and detects the material to be heated that is charged through the charging door.

Next, the operation of an embodiment of the present invention configured as described above will be explained.

As shown in FIG. 5, the control device 20 operates the flue damper 4 at a certain inclination as shown in the formula below when an open or close notice signal is input from the notice transmitter 9.

? Changes depending on the slope.

When a signal indicating the opening degree of the charging door 2 is inputted from the pulse transmitter 8, the flue damper 4 is operated according to the following formula.

ΔX=K・ΔP...2 However, ΔP: Amount of change in charging door 4 The variables in equations 1 and 2 above are determined by the current position of the flue damper 4.
This is because due to the nature of the flue damper 4, even if it is moved by the same angle, the opening degree differs depending on the position.
Also, while formulas 1 and 2 are being executed, the conventional furnace internal pressure control is still operating, and is added to that operation.

That is, the control of the damper 4 according to Equation 2 is intended to compensate for the time delay that occurs in conventional PI control using the detector 5 and to provide an accurate control response. However, when damper control based on Equation 2 is strictly considered, in reality, the control of the damper 4 does not follow changes in the furnace internal pressure due to opening and closing of the charging door, and a time delay still occurs in the control. The control based on Equation 1 is intended to compensate for the time delay caused by the control based on Equation 2, and the charging door 2
The damper 4 is controlled based on the output that changes at a predetermined slope just before the damper 4 is opened or closed, thereby obtaining an accurate control response. Note that α in Equation 1 is determined by the sizes of the furnace 1, the charging door 2, etc., the position of the damper 4, etc., and can be obtained by means such as experimenting with actual equipment.

The above embodiment is for controlling the internal pressure of a heating furnace, but it goes without saying that it can be applied to any device as long as the fluctuation factor can be detected positionally, and the same effect can be achieved. .

As described above, according to the present invention, the first calculation device generates an output with a predetermined slope based on the opening/closing operation warning signal immediately before the charging door is opened/closed, and the By providing a second calculation device that calculates and outputs the degree of opening, and an adjustment device that adjusts the opening degree of the damper based on the outputs of the first and second calculation devices, the It is possible to provide an internal pressure control device that can always keep the furnace internal pressure constant by adjusting the opening degree of the damper.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of equipment to which the present invention is applied, FIGS. 2 and 3 are block diagrams showing an example of a conventional internal pressure control device, and FIGS.
The figure is a block diagram showing an internal pressure control device in one embodiment of the present invention. In the figure, 1 is a heating furnace as a chamber, 4 is a flue damper, and 20 is a control device as a calculation device and an adjustment device. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] 1. In a device that maintains the internal pressure of a container chamber constant by adjusting the opening degree of a damper attached to a part of the device, the opening/closing operation is performed immediately before the loading door of the container chamber starts to move. a warning transmitter that generates a warning signal; a first computing device that generates an output that changes at a predetermined slope according to the warning signal generated by the warning transmitter; and a first computing device that detects movement of the charging door and opens it. an internal pressure control device comprising: a second calculation device that calculates and outputs the degree; and an adjustment device that adjusts the opening degree of the damper based on the outputs of the first and second calculation devices. . 2. The internal pressure control device according to claim 1, wherein the chamber is a heating furnace.