JPH05149513A - Nozzle drive control device in nozzle movable type burner - Google Patents

Abstract

PURPOSE:To obtain a nozzle drive control device in a nozzle movable type burner which is capable of protecting stepping motor coils from burning. CONSTITUTION:A proper combustion quantity difference arithmetic operation means 21 computes the present proper combustion quantity and the previous proper combustion quantity calculated by a proper combustion quantity arithmetic operation means 18. A pulse count correction means 22 corrects the number of pulses per one cycle read by a pulse count read means 20 based on the result of arithmetic operation by the proper combustion quantity difference arithmetic operation means 21. A drive pulse supply means 23 moves by a required movable variable of a nozzle computed by a required movable variable arithmetic operation means 19 or supplies a drive pulse to a stepping motor 4 until the drive pulse corrected by the pulse count correction means 22 is supplied to the stepping motor 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle drive control device for a nozzle moving burner.

[0002]

2. Description of the Related Art Conventionally, in a nozzle moving type burner in which a nozzle for spraying fuel oil is moved by a stepping motor to change the amount of fuel oil passing through an opening of a diaphragm plate to adjust the combustion amount, a combustion operation is performed. At some times, the proper combustion amount was calculated every predetermined time, and the nozzle was moved by the stepping motor based on the calculation. That is, the number of drive pulses to be supplied to the stepping motor is determined in advance every predetermined time, and the nozzle is moved by the required movement amount at every predetermined time, or until the supply of the predetermined number of pulses is completed, The drive pulse was supplied to the stepping motor.

[0003]

Since [0008] However the amount of burn control is subtle, in the conventional configuration, as shown in FIG. 5, for each calculation period T ₁ of the proper combustion amount over time of the most This often results in the application of a drive pulse to the stepping motor, and the drive voltage V ₁ is applied to the stepping motor substantially at all times, and the coil of the stepping motor may overheat and burn. Actually, drive pulses are sequentially and cyclically applied to a plurality of coils of the stepping motor in a predetermined short cycle, but in FIG. 5, the number of drive pulses is expressed in a small number for easy understanding. There is. Further, in FIG. 5, V ₂ is a voltage applied to the coil of the stepping motor at the time of stop.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a nozzle drive control device for a nozzle moving type burner which can prevent a coil of a stepping motor from being burnt out.

[0005]

SUMMARY OF THE INVENTION The present invention is a nozzle moving type in which a nozzle for spraying fuel oil is moved by a stepping motor to change the amount of fuel oil passing through an opening of an aperture plate to adjust the combustion amount. In the burner, a pulse number storage means for storing in advance the number of drive pulses per cycle to be supplied to the stepping motor according to the proper combustion amount, and an appropriate combustion amount calculation for computing the proper combustion amount at every predetermined time. Means, a necessary movement amount calculation means for calculating a necessary movement amount of the nozzle based on the proper combustion amount calculated by the proper combustion amount calculation means, and a proper combustion amount calculated by the proper combustion amount calculation means. Pulse number reading means for reading the number of drive pulses per cycle supplied to the stepping motor from the pulse number storage means, A proper combustion amount difference calculating means for calculating the difference between the proper combustion amount of this time calculated by the proper combustion amount calculating means and the last proper combustion amount, and the number of pulses based on the calculation result by the proper combustion amount difference calculating means. A pulse number correcting means for correcting the number of drive pulses per cycle read by the reading means, and the nozzle is moved by the required moving amount calculated by the necessary moving amount calculating means, or the stepping motor. And a drive pulse supply means for supplying a drive pulse to the stepping motor until the drive pulse is supplied by the number of pulses corrected by the pulse number correction means, and the difference between the appropriate combustion amount of this time and the appropriate combustion amount of the previous time is provided. Is small, the number of drive pulses supplied to the stepping motor is reduced.

[0006]

The pulse number storage means stores in advance the number of drive pulses per cycle to be supplied to the stepping motor according to the proper combustion amount. The appropriate combustion amount calculation means calculates the appropriate combustion amount every predetermined time. The required movement amount calculation means calculates the required movement amount of the nozzle based on the proper combustion amount calculated by the proper combustion amount calculation means. The pulse number reading means reads, from the pulse number storage means, the number of drive pulses per cycle supplied to the stepping motor in accordance with the proper combustion amount calculated by the proper combustion amount calculation means. The appropriate combustion amount difference calculating means calculates the difference between the current appropriate combustion amount calculated by the appropriate combustion amount calculating means and the previous appropriate combustion amount. The pulse number correcting means corrects the pulse number of the driving pulse per one cycle read by the pulse number reading means based on the calculation result by the appropriate combustion amount difference calculating means. The drive pulse supply means is
The driving pulse is supplied to the stepping motor until the nozzle moves by the required moving amount calculated by the necessary moving amount calculation means or the driving pulse is supplied by the pulse number corrected by the pulse number correction means to the stepping motor. ..

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in the drawings. FIG. 2 is a schematic cross-sectional view of a nozzle moving burner including a nozzle drive control device according to an embodiment of the present invention.
The burner 1 is composed of a nozzle 2 and a diaphragm plate 3. The nozzle 2 is driven back and forth (left and right direction in FIG. 2) by a stepping motor 4 to control the combustion amount. The nozzle 2 communicates with a closed oil sump 6 via an oil conduit 5, and a pump 7 is installed in the oil conduit 5. Fuel oil such as petroleum supplied to the nozzle 2 through the oil conduit 5 by the pump 7 is sprayed from the nozzle 2 and partly blocked by the diaphragm plate 3 and returned to the oil sump 6 through the return pipe 8. .. The oil sump 6 communicates with the space around the nozzle 2 via an air vent pipe 9. That is, since the amount of fuel oil blocked by the throttle plate 3 changes depending on the position of the nozzle 2, the amount of fuel oil passing through the opening 3a of the throttle plate 3 changes, and the combustion amount in the combustion chamber 10 changes. is there. Combustion air is supplied by a blower fan 11 to a combustion chamber 10 in which the fuel oil injected from the nozzle 2 and passed through the opening 3a of the diaphragm plate 3 is burned, and the supply amount of this combustion air is controlled by the air volume control damper 12. Controlled. The air volume control damper 12 is driven by a stepping motor 13. The stepping motors 4 and 13 are connected to a controller 14 having a microcomputer and driven by the controller 14. That is, the controller 14 constitutes a nozzle drive control device for performing feedforward and feedback control of the stepping motor 4. Further, the oil conduit 5 is provided with an oil temperature sensor 15.

FIG. 1 is a block diagram of a nozzle drive control device according to an embodiment of the present invention. The nozzle drive control device supplies a stepping motor 4 according to an appropriate combustion amount.
A pulse number storage unit 17 that stores in advance the number of drive pulses per cycle, an appropriate combustion amount calculation unit 18 that calculates an appropriate combustion amount at every predetermined time, and an operation performed by the appropriate combustion amount calculation unit 18 A required movement amount calculation means 19 for calculating the required movement amount of the nozzle 2 based on the proper combustion amount,
A pulse number reading means 20 for reading the pulse number of the driving pulse supplied to the stepping motor 4 per one cycle from the pulse number storage means 17 in accordance with the appropriate combustion amount calculated by the appropriate combustion amount calculation means 18, and an appropriate combustion amount calculation An appropriate combustion amount difference calculating means 21 for calculating a difference between the appropriate combustion amount of this time calculated by the means 18 and the appropriate combustion amount of the previous time,
A pulse number correction unit 22 that corrects the pulse number of the drive pulse per cycle read by the pulse number reading unit 20 based on the calculation result of the appropriate combustion amount difference calculation unit 21, and a movement amount calculation unit that requires the nozzle 2 Drive pulse supply means for supplying drive pulses to the stepping motor 4 until the stepping motor 4 is moved by the required movement amount, or the drive pulse is supplied to the stepping motor 4 by the number of pulses corrected by the pulse number correcting means 22. Two
3 and 3. Among these means, the pulse number storage means 17 is constituted by a part of a storage device (not shown), and the other means are realized by software by the microcomputer of the controller 14. The controller 14 uses the stepping motor 4 based on input signals from a remote controller (not shown) and various sensors.
Not only this, it controls the entire nozzle moving burner or the hot water supply apparatus equipped with the nozzle moving burner.

Next, the operation will be described. Pulse number storage means 1
In FIG. 7, the number of drive pulses per cycle supplied to the stepping motor 4 according to the appropriate combustion amount is stored in advance as a table. During the combustion operation, first, the proper combustion amount calculation means 18 calculates the proper combustion amount based on the input signals from the remote controller, various sensors and the like. As a result, the required movement amount calculation means 19 calculates the required movement amount of the nozzle 2 based on the proper combustion amount calculated by the proper combustion amount calculation means 18 and the current position of the nozzle 2, and determines the movement direction. .. Further, the pulse number reading means 20 causes the stepping motor 4 to operate based on the proper combustion amount calculated by the proper combustion amount calculating means 18.
The pulse number of the drive pulse per one cycle supplied to is read from the pulse number storage means 17. Then, the appropriate combustion amount difference calculating means 21 calculates the difference between the current appropriate combustion amount calculated by the appropriate combustion amount calculating means 18 and the previous appropriate combustion amount stored in the storage device (not shown). Thereby, the pulse number correcting means 22 corrects the pulse number of the drive pulse per one cycle read from the pulse number storing means 17 by the pulse number reading means 20 based on the calculation result by the appropriate combustion amount difference calculating means 21. To do. As a result, the drive pulse supply means 23 supplies a drive pulse to the stepping motor 4 in accordance with the moving direction calculated by the required movement amount calculation means 19. As a result, the stepping motor 4 is driven, the nozzle 2 moves, and the amount of combustion changes. Then, when the nozzle 2 moves by the required moving amount calculated by the required moving amount calculating means 19 or when the driving pulse is supplied to the stepping motor 4 by the number of pulses corrected by the pulse number correcting means 22, the driving pulse The supply means 23 stops the supply of the drive pulse to the stepping motor 4. That is, when the difference between the proper combustion amount of this time and the proper combustion amount of the previous time is small, the number of drive pulses supplied to the stepping motor 4 decreases. Therefore, the ratio of the drive time to the stop time of the stepping motor 4 becomes small, so that burnout due to overheating of the coil of the stepping motor 4 can be prevented.

Regarding the operation of the nozzle drive control device,
A more specific description will be given with reference to the flowchart of FIG. First, the proper combustion amount calculation means 18 calculates the proper combustion amount (step S1). Next, the required movement amount calculation means 1
9 calculates the required movement amount and direction of the nozzle 2 based on the proper combustion amount calculated by the proper combustion amount calculation means 18 in step S1 and the current position of the nozzle 2 (step S2). Next, the pulse number reading means 20 supplies 1 to the stepping motor 4 based on the proper combustion amount calculated by the proper combustion amount calculation means 18 in step S1.
The number of drive pulses per cycle is read from the pulse number storage means 17 (step S3). In addition, 1 cycle means
This is the time for one round of the flowchart of FIG. Next, the appropriate combustion amount difference calculating means 21 calculates the difference between the appropriate combustion amount calculated by the appropriate combustion amount calculating means 18 in step S1 and the previous appropriate combustion amount stored in the storage device, and the difference is calculated. It is determined whether or not the value is equal to or less than the predetermined value A (step S
4). If the difference is less than or equal to the predetermined value A, the pulse number correction means 2
2 is the pulse number of the drive pulse per one cycle read by the pulse number reading means 20 in step S3,
It is divided by a preset constant X (step S5). However, X is a number greater than 1, and the quotient divided by the constant X is rounded off to an integer. Next, a timer for measuring the cycle T ₁ is started (step S6). Next, the drive pulse supply means 23, based on the movement direction of the nozzle 2 calculated by the required movement amount calculation means 19 in step S2,
A drive pulse having a predetermined pulse width is sequentially and cyclically supplied to each coil of the stepping motor 4 in a predetermined cycle (step S7), and it is determined whether the supply of the drive pulse having the pulse number corrected in step S5 is completed. (Step S8),
If the supply is not completed, it is judged whether or not the nozzle 2 has moved by the required movement amount calculated in step S2 (step S9). If it has moved, the stop voltage V ₂ of FIG. 4 is applied to the coil of the stepping motor 4. Is applied (step S1
0). Thus, the position of the nozzle 2 changes, the amount of fuel oil passing through the opening 3a of the diaphragm plate 3 changes, and the amount of combustion changes. The drive pulse has a voltage V _{1 as shown} in FIG.
In addition, in practice, drive pulses are sequentially and cyclically applied to a plurality of coils of the stepping motor 4 in a predetermined short cycle, but in FIG. 4, the number of drive pulses is expressed in a small number for easy understanding. ing. Next, it is determined whether or not the timer started in step S6 has timed out (step S11). If the time has expired, the proper combustion amount calculated by the proper combustion amount calculation means 18 in step S1 is stored in the storage device. Stored in (step S1
2) Return to step S1. If it is determined in step S11 that the timer has not expired, the process returns to step S11. In step S9, the nozzle 2
If it is determined that has not moved by the required movement amount calculated in step S2, the process returns to step S8. Step S8
If it is determined in step S5 that the supply of the drive pulses of the pulse number corrected in step S5 is complete, the process proceeds to step S10. If it is determined in step S4 that the difference between the proper combustion amount of this time and the proper combustion amount of the previous time is not equal to or smaller than the predetermined value A, the process proceeds to step S6 without correcting the pulse number.

As described above, when the change in the proper combustion amount is small, the number of drive pulses supplied to the stepping motor 4 is reduced, so that the ratio of the drive time to the stop time of the stepping motor 4 becomes small as shown in FIG. Therefore, it is possible to favorably prevent burnout due to overheating of the coil of the stepping motor 4.

In the above embodiment, when the change in the proper combustion amount is small, the pulse number correcting unit 22 determines the pulse number according to the proper combustion amount read from the pulse number storage unit 17 by the pulse number reading unit 20. Although it is configured to be divided by the constant X, a plurality of constants may be stored and the constant may be switched according to the amount of change in the appropriate combustion amount.
Alternatively, a mathematical expression may be stored instead of the constant, and the dividing number may be changed steplessly in proportion to the difference between the proper combustion amount of this time and the proper combustion amount of the previous time.

[0013]

According to the present invention, which has the above-described structure, the nozzle for spraying fuel oil is moved by a stepping motor to change the amount of fuel oil passing through the aperture of the diaphragm plate to adjust the amount of combustion. In the burner, a pulse number storage means for storing in advance the number of drive pulses per cycle to be supplied to the stepping motor according to the proper combustion amount, and a proper combustion amount calculation for computing the proper combustion amount at every predetermined time. Means, a necessary movement amount calculation means for calculating a necessary movement amount of the nozzle based on the proper combustion amount calculated by the proper combustion amount calculation means, and stepping according to the proper combustion amount calculated by the proper combustion amount calculation means. Pulse number reading means for reading the number of drive pulses per cycle to be supplied to the motor from the pulse number storage means, and appropriate combustion amount calculation means The appropriate combustion amount difference calculating means for calculating the difference between the present proper combustion amount calculated by the above and the previous proper combustion amount, and the pulse number reading means based on the calculation result by the appropriate combustion amount difference calculating means. Further, the pulse number correcting means for correcting the pulse number of the driving pulse per one cycle, and the nozzle moves by the required moving amount calculated by the necessary moving amount calculating means, or the stepping motor is corrected by the pulse number correcting means. The driving pulse supply means for supplying the driving pulse to the stepping motor until the driving pulse is supplied by the number of pulses, and the driving pulse supplied to the stepping motor when the difference between the proper combustion amount of this time and the last proper combustion amount is small. The number of pulses of the stepping motor is reduced when the difference in the appropriate combustion amount is small. Since the ratio of the driving time is reduced, it can be favorably prevented burnout due to overheating of the stepping motor coil.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a nozzle drive control device according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a nozzle moving burner including a nozzle drive control device according to an embodiment of the present invention.

FIG. 3 is a flowchart illustrating an operation of the nozzle drive control device in the embodiment of the present invention.

FIG. 4 is a timing chart of a drive pulse that is an output of the nozzle drive control device in the embodiment of the present invention.

FIG. 5 is a timing chart of drive pulses output from a conventional nozzle drive control device.

[Explanation of symbols]

 2 nozzle 3 diaphragm plate 3a opening 4 stepping motor 17 pulse number storage means 18 proper combustion amount calculation means 19 necessary movement amount calculation means 20 pulse number reading means 21 proper combustion amount difference calculation means 22 pulse number correction means 23 drive pulse supply means

Claims (1)

[Claims] 1. A nozzle moving burner that adjusts the combustion amount by changing the amount of fuel oil passing through the opening of a diaphragm plate by moving a nozzle for spraying fuel oil with a stepping motor, according to an appropriate combustion amount. Pulse number storage means for storing in advance the number of drive pulses per cycle to be supplied to the stepping motor, an appropriate combustion amount calculation means for calculating an appropriate combustion amount at every predetermined time, and an appropriate combustion amount calculation A required movement amount calculation means for calculating the required movement amount of the nozzle based on the proper combustion amount calculated by the means, and the stepping motor supplied to the stepping motor according to the proper combustion amount calculated by the proper combustion amount calculation means 1
A pulse number reading means for reading the number of drive pulses per cycle from the pulse number storage means, and an appropriate value for calculating the difference between the appropriate combustion amount of this time calculated by the appropriate combustion amount calculation means and the previous appropriate combustion amount. Combustion amount difference calculating means, pulse number correcting means for correcting the pulse number of the drive pulse per one cycle read by the pulse number reading means based on the calculation result by the appropriate combustion amount difference calculating means, and the nozzle. The drive pulse is supplied to the stepping motor until it moves by the required travel amount calculated by the necessary travel amount calculating means or the drive pulse is supplied by the pulse number corrected by the pulse number correcting means to the stepping motor. When the difference between the appropriate combustion amount of this time and the appropriate combustion amount of the previous time is small, Tsu nozzle drive controller in the nozzle moving type burner, characterized in that it has a configuration that reduces the number of pulses of the drive pulse supplied to ping the motor.