JPH05118530A - Nozzle driving controller in nozzle moving type burner - Google Patents

Abstract

PURPOSE:To provide the above nozzle driving controller which is sufficiently capable of preventing the damage caused by burning the coils of a stepping motor in a nozzle moving type burner. CONSTITUTION:A proper quantity of combustion calculator 17 calculates a proper quantity of combustion. A required quantity of movement operator 18 calculates a required quantity of movement of a nozzle based on a proper quantity of combustion that is calculated by the proper quantity of combustion operator 17. A drive pulse supply means 19 supplies drive pulses to a stepping motor according to a required quantity of movement operated by the proper quantity of combustion operation means 17. A proper quantity of combustion difference operator 20 operates the difference of the proper quantity of fuel consumption of this time and previous proper quantity of combustion that are operated by the proper quantity of combustion operator 17. A controller 21 for time distance between operations make variable the time up to the next proper quantity of combustion by the proper quantity of combustion operator 17 based on the results of calculation by the proper quantity of combustion difference operator 20.

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.

[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, the drive pulse is sequentially and cyclically applied to a plurality of coils of the stepping motor in a predetermined short cycle, but in FIG. 5, the entire drive pulse application period is set to one in order to make the description easy to understand. Represented as a pulse. 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, an appropriate combustion amount calculation means for calculating an appropriate combustion amount, a necessary movement amount calculation means for calculating a necessary movement amount of the nozzle based on the appropriate combustion amount calculated by the appropriate combustion amount calculation means, and A drive pulse supply means for supplying a drive pulse to the stepping motor according to the required movement amount calculated by the movement amount calculation means, a current proper combustion amount calculated by the proper combustion amount calculation means, and a previous proper combustion amount. And an appropriate combustion amount difference calculating means for calculating the difference between the appropriate combustion amount difference calculating means and the appropriate combustion amount difference calculating means, and based on the calculation result by the appropriate combustion amount difference calculating means. And a calculation interval control means for varying the time until the calculation of the combustion amount, and when the difference between the proper combustion amount of this time and the previous proper combustion amount is small, the time until the calculation of the next proper combustion amount is lengthened. It is characterized by doing.

[0006]

The proper combustion amount calculation means calculates the proper combustion amount. 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 drive pulse supply means supplies a drive pulse to the stepping motor according to the required movement amount calculated by the required movement 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 calculation interval control means varies the time until the next calculation of the proper combustion amount by the proper combustion amount calculation means, based on the calculation result by the proper combustion amount difference calculation means. When the difference between the proper combustion amount of this time and the proper combustion amount of the previous time is small, the ratio of the drive time of the stepping motor to the stop time is controlled by increasing the time until the calculation of the next proper combustion amount. To prevent burnout due to overheating of the coil.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in the drawings. FIG. 1 is a schematic cross-sectional view of a nozzle moving burner having 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. 1) 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. An oil temperature sensor 15 is provided in the oil conduit 5.

FIG. 2 is a block diagram of a nozzle drive control device according to an embodiment of the present invention. The nozzle drive control device includes an appropriate combustion amount calculation means 17 for calculating an appropriate combustion amount and the appropriate combustion amount calculation means 17 Required moving amount calculating means 18 for calculating the required moving amount of the nozzle 2 based on the appropriate combustion amount calculated by the above, and a drive pulse for the stepping motor 4 according to the required moving amount calculated by the necessary moving amount calculating means 18. And a drive pulse supply means 19 for supplying the appropriate combustion amount, a proper combustion amount difference calculation means 20 for calculating a difference between the proper combustion amount of this time calculated by the proper combustion amount calculation means 17, and a proper combustion amount of the previous time, and a proper combustion amount difference. And a calculation interval control unit 21 for varying the time until the next calculation of the proper combustion amount by the proper combustion amount calculation unit 17 based on the calculation result by the calculation unit 20. Luo respective means are software-implemented by the microcomputer of the controller 14. The controller 14 controls not only the stepping motor 4 but also the nozzle moving burner or the entire water heater including the nozzle moving burner based on input signals from a remote controller (not shown) and various sensors. To do.

Next, the operation will be described. During the combustion operation, first, the proper combustion amount calculation means 17 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 18
Calculates the required movement amount of the nozzle 2 and determines the movement direction based on the proper combustion amount calculated by the proper combustion amount calculation means 17 and the current position of the nozzle 2. As a result, the drive pulse supply means 19 is operated by the required movement amount calculation means 1
A drive pulse is supplied to the stepping motor 4 according to the required moving amount and moving direction calculated by 8.
As a result, the stepping motor 4 is driven, the nozzle 2 moves, and the amount of combustion changes. On the other hand, the appropriate combustion amount difference calculating means 20 calculates the difference between the appropriate combustion amount of this time calculated by the appropriate combustion amount calculating means 17 and the previous appropriate combustion amount stored in the storage device (not shown). Thereby, the calculation interval control means 21 varies the time until the next calculation of the proper combustion amount by the proper combustion amount calculation means 17, based on the calculation result by the proper combustion amount difference calculation means 20. 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 time until the calculation of the proper combustion amount of the next time is lengthened. Therefore, when the change in the proper combustion amount is small, the calculation cycle of the proper combustion amount becomes long, and as a result, 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 17 calculates the proper combustion amount (step S1). Next, the appropriate combustion amount difference calculating means 20 calculates the difference between the appropriate combustion amount calculated by the appropriate combustion amount calculating means 17 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 smaller than the predetermined value A (step S2). Difference is a predetermined value A
In the following cases, the calculation interval control means 21 starts the timer t ₁ corresponding to the calculation cycle T ₁ in FIG. 4 (step S3). Next, the required movement amount calculation means 18 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 17 in step S1 and the current position of the nozzle 2 (step S4). Next, the drive pulse supply means 19 supplies each coil of the stepping motor 4 with a predetermined pulse width in a predetermined cycle based on the required movement amount and direction of the nozzle 2 calculated by the necessary movement amount calculation means 18 in step S4. The drive pulses are sequentially and cyclically supplied (step S5), and it is judged whether or not the supply of the required number of drive pulses is completed (step S6). When the supply is completed, the coil of the stepping motor 4 is supplied to the coil shown in FIG.
The stop voltage V ₂ is applied (step S7). As a result, the nozzle 2 moves to a desired position and the aperture 3a of the diaphragm plate 3
The amount of fuel oil passing through changes the amount of combustion. The drive pulse has a voltage V _{1 as shown} in FIG. Further, actually, the drive pulse is sequentially and cyclically applied to the plurality of coils of the stepping motor 4, but in FIG. 4, the entire application period of the drive pulse is represented as one pulse in order to make the description easy to understand. There is. Next, the calculation interval control means 21 determines whether or not the timer t ₁ started in step S3 has expired (step S3).
8) If the time is up, the proper combustion amount calculated by the proper combustion amount calculating means 17 in step S1 is stored in the storage device (step S9), and the process returns to step S1. If it is determined in step S8 that the timer t ₁ has not expired, the process returns to step S8. If it is determined in step S6 that the supply of the required number of drive pulses has not been completed, the process returns to step S6. If it is determined in step S2 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 calculation interval control means 21 causes the timer t corresponding to the calculation cycle T ₂ of FIG.
₂ is started (step S10), and the process proceeds to step S4. When the timer t ₂ is started in step S10, it is determined in step S8 whether or not the timer t ₂ is up.

As described above, when the change in the proper combustion amount is small, the calculation cycle of the proper combustion amount is lengthened from T ₁ to T ₂ , so that the ratio of the drive time to the stop time of the stepping motor 4 is as shown in FIG. The size of the coil is reduced, and the burnout due to overheating of the coil of the stepping motor 4 can be effectively prevented.

In the above embodiment, the calculation cycle of the proper combustion amount is switched to two stages of T ₁ and T ₂ , but it may be switched to three stages or more, or the present proper combustion amount and the previous proper combustion amount. It may be changed steplessly in proportion to the difference from the amount.

[0013]

According to the present invention, which has the above-described structure, the proper combustion amount calculating means for calculating the proper combustion amount, and the necessary moving amount of the nozzle are calculated based on the proper combustion amount calculated by the proper combustion amount calculating means. Required moving amount calculation means, drive pulse supply means for supplying a drive pulse to the stepping motor in accordance with the required one movement amount calculated by the required movement amount calculation means, and the proper current time calculated by the proper combustion amount calculation means. A proper combustion amount difference calculating means for calculating the difference between the combustion amount and the previous proper combustion amount, and the calculation of the next proper combustion amount by the proper combustion amount calculating means based on the calculation result by the proper combustion amount difference calculating means. Equipped with a calculation interval control means for varying the time, and when the difference between the proper combustion amount of this time and the previous proper combustion amount is small, the time until the calculation of the next proper combustion amount is lengthened, Since the ratio of the driving time to the stop time of the stepping motor when the difference between the positive combustion amount is small is reduced, it can be favorably prevented burnout due to overheating of the stepping motor coil.

[Brief description of drawings]

FIG. 1 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. 2 is a configuration diagram of 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 Throttle Plate 3a Opening 4 Stepping Motor 17 Proper Combustion Amount Calculation Means 18 Necessary Movement Amount Calculation Means 19 Drive Pulse Supply Means 20 Proper Combustion Amount Difference Calculation Means 21 Calculation Interval Control Means

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] January 8, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

The operation of the nozzle drive control device will be described more specifically with reference to the flowchart of FIG. First, the proper combustion amount calculation means 17 calculates the proper combustion amount (step S1). Next, the appropriate combustion amount difference calculating means 20 calculates the difference between the appropriate combustion amount calculated by the appropriate combustion amount calculating means 17 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 smaller than the predetermined value A (step S2). If the difference is less than or equal to the predetermined value A, the calculation interval control means 21 starts the timer t ₂ corresponding to the calculation cycle T ₂ in FIG. 4 (step S3). Next, the required movement amount calculation means 18 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 17 in step S1 and the current position of the nozzle 2 (step S
4). Next, the drive pulse supply means 19 supplies each coil of the stepping motor 4 with a predetermined pulse width at a predetermined cycle based on the required movement amount and direction of the nozzle 2 calculated by the necessary movement amount calculation means 18 in step S4. The drive pulses are sequentially and cyclically supplied (step S5), it is judged whether or not the supply of the required number of drive pulses is completed (step S6), and when the supply is completed, the coil of the stepping motor 4 is supplied with the voltage shown in FIG. Apply the stop voltage V ₂ (step S
7). As a result, the nozzle 2 moves to a desired position, 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. Further, in practice, the drive pulse is sequentially and cyclically applied to the plurality of coils of the stepping motor 4, but in FIG. 4, the entire drive pulse application period is represented as one pulse in order to make the description easy to understand. There is. Then calculating interval control means 21, a timer t ₂ that is started in step S3, it is determined whether the time is up (step S8), and step S if the time is up
The appropriate combustion amount calculated by the appropriate combustion amount calculation means 17 in 1 is stored in the storage device (step S9), and step S9
Return to 1. Incidentally it is judged that the timer t ₂ has not timed at step S8, the flow returns to step S8. If it is determined in step S6 that the supply of the required number of drive pulses has not been completed, the process returns to step S6. Also if it is determined that the difference from the proper combustion amount and the previous proper combustion amount of time in step S2 is not less than a predetermined value A, calculating the interval control unit 21, a timer t ₁ corresponding to the calculation period T ₁ of the 4 Start (Step S1
0), and proceeds to step S4. When the timer t ₁ is started in step S10, it is determined in step S8 whether or not the timer t ₁ is up.

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

Claims (1)

[Claims] 1. A proper moving amount is calculated in a nozzle moving type burner which adjusts the burning amount by changing the amount of the fuel oil passing through the opening of the diaphragm plate by moving the nozzle for spraying the fuel oil with a stepping motor. And a required movement amount calculation means for calculating the required movement amount of the nozzle based on the appropriate combustion amount calculated by the appropriate combustion amount calculation means, and the required movement amount calculation means. A drive pulse supply means for supplying a drive pulse to the stepping motor according to the required movement amount, and a proper combustion for calculating a difference between the proper combustion amount of this time calculated by the proper combustion amount calculation means and the previous proper combustion amount. Based on the amount difference calculation means and the calculation result by the appropriate combustion amount difference calculation means, the time until the next calculation of the appropriate combustion amount by the appropriate combustion amount calculation means is performed. Nozzle movement characterized in that it comprises variable calculation interval control means, and when the difference between the proper combustion amount of this time and the previous proper combustion amount is small, the time until calculation of the next proper combustion amount is lengthened. Nozzle drive control device in a burner.