JPH04270812A - Method of initial adjustment of gun type burner - Google Patents

Abstract

PURPOSE:To present a method of initial adjustment of a gun type burner by which the subsequent combustion control can be executed well regardless of the scatter in the characteristics of respective burners by carrying out the initial adjustment before shipment or at the time of replacing nozzle. etc. CONSTITUTION:In the first process a controller 10 drives firstly a stepping motor 27 from a standard position by a first specified step. Next, the operator adjusts the position of a nozzle 14 manually so as to bring the quantity of combustion of the fuel to a first specified quantity of combustion. In the later second process at first the controller 10 drives the stepping motor 27 so as to bring the quantity of combustion of fuel to a second specified quantity of combustion. And the controller 10 stores in memory the number of the steps at that time. This second process is carried out at least for the second specified quantity of combustion.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for initial adjustment of a gun-type burner.

0002

[Prior Art] A conventional gun type burner includes a shielding plate having holes, a nozzle that can manually adjust the distance between the shielding plate and the nozzle that injects fuel, and a nozzle that injects fuel by moving the nozzle to adjust the distance between the shielding plate and the shielding plate. A configuration that includes a stepping motor that changes the amount of fuel and a control device that drives the stepping motor, and controls the combustion amount by changing the distance between the shield plate and the nozzle to change the amount of fuel that passes through the hole in the shield plate. Met.

0003

[Problems to be Solved by the Invention] However, in conventional gun-type burners, even if there are two burners of the same type as shown in FIG. The relationship between the amount of fuel passing through the holes, that is, the amount of combustion, is different, and combustion control is sometimes difficult. In other words, the control device drives the stepping motor by a combination of feedforward control and feedback control, but the feedforward control is performed by uniformly determining the relationship between the nozzle position and the combustion amount in advance, and the variation in characteristics of individual burners is eliminated. If an attempt is made to absorb this through feedback control, the amount of adjustment by feedback control is too large and it takes a long time to reach the target combustion amount, resulting in poor control response and poor combustion control. there were. In addition, the distance the nozzle moves by the stepping motor is small, and if the initial setting of the nozzle position for each burner is not appropriate, the range of nozzle movement by the stepping motor will not match the desired combustion amount adjustment range, resulting in control failure. There were cases where this was not possible.

[0004] The present invention provides an initial adjustment method for a gun-type burner, which allows subsequent combustion control to be performed satisfactorily regardless of variations in the characteristics of individual burners, by carrying out the method before shipment or when replacing the nozzle. The purpose is to provide

[0005]

[Means for Solving the Problems] The present invention provides a shielding plate having a hole, a nozzle that can manually adjust the distance between the shielding plate and the nozzle that injects fuel, and a nozzle that can be moved between the nozzle and the shielding plate. A stepping motor that changes the distance and a control device that drives the stepping motor are provided, and combustion is performed by changing the distance between the shielding plate and the nozzle to change the amount of fuel passing through the hole of the shielding plate. When initially adjusting a gun-type burner configured to control the amount of fuel, the stepping motor is driven by the control device by a first predetermined number of steps from the reference position, and in this state, the amount of fuel burned reaches the first predetermined combustion amount. a first stroke in which the position of the nozzle is manually adjusted so that The present invention is characterized in that the control device performs the storing operation with respect to at least one type of the second predetermined combustion amount.

[0006]

[Operation] In the first stroke, the control device first drives the stepping motor by a first predetermined number of steps from the reference position. Next, the operator manually sets the fuel combustion amount to the first level.
Adjust the position of the nozzle so that the predetermined combustion amount is achieved. In the subsequent second stroke, the control device first drives the stepping motor so that the amount of fuel burned becomes the second predetermined amount. The control device then stores the number of steps at that time. This second stroke is performed for at least one type of second predetermined combustion amount.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below based on embodiments shown in the drawings. FIG. 2 is a schematic overall configuration diagram of a water heater equipped with a gun-type burner adjusted by the initial adjustment method according to an embodiment of the present invention, in which the heat exchanger 1 is connected to the gun-type burner 2.
and pipe 3. An inlet pipe 4 is connected to one end of the pipe 3, and an outlet pipe 5 is connected to the other end of the pipe 3.
is connected. The water inlet pipe 4 is equipped with a flow rate detector 6 and a water temperature detector 7 consisting of a thermistor, and the hot water outlet pipe 5 is equipped with a hot water temperature detector 8 consisting of a thermistor and a flow rate adjustment valve 9. . Flow rate detector 6 and water temperature detector 7
The output ends of the and hot water temperature detector 8 are connected to the input ends of a control device 10 equipped with a microcomputer, etc., and the output ends of the control device 10 are connected to the gun type burner 2 and the flow rate regulating valve 9.
are connected to each input end. A remote controller 11 is connected to the control device 10.

The control device 10 calculates the required output number, that is, the amount of fuel to be supplied for combustion, based on detection signals from the flow rate detector 6, water temperature detector 7, and remote controller 11. Then, a control signal is output to the gun type burner 2 based on the calculation result, and the nozzle position and damper opening degree are adjusted by feedforward control. Further, the control device 10 calculates the difference between the outlet temperature and the set temperature based on the detection signal from the hot water temperature detector 8, outputs a control signal to the gun type burner 2 based on the calculation result, and controls the nozzle by feedback control. Finely adjust the position and damper opening. The control device 10 also controls the flow rate regulating valve 9 to prevent excessive outflow.

FIG. 1 is a configuration diagram of a gun type burner 2, in which a nozzle 14 is attached to one end of a nozzle adapter 13, and an injection port 15 of the nozzle 14 communicates with a fuel pipe 16. Nozzle adapter 13 is nozzle adapter guide 1
7, and a shielding plate 18 is attached to the nozzle adapter guide 17. Shielding plate 18
A hole 19 facing the injection port 15 of the nozzle 14 is formed in the nozzle adapter guide 17, and an ignition rod 20 whose tip is located near the hole 19 of the shielding plate 18 is attached to the nozzle adapter guide 17. The space between the nozzle 14 and the shielding plate 18 communicates with a recovery pipe 21, and an annular flange 22 is provided protruding near the other end of the nozzle adapter 13. A coil spring 23 is interposed between the nozzle adapter guide 17 and the flange 22 to bias the nozzle adapter 13 toward the other end (right side in FIG. 1), and a male thread is attached to the outer periphery of the other end of the nozzle adapter 13. 25 is formed. Male thread 25
An adjustment screw 26 is screwed into the. A male thread 29 is formed in the middle of the output shaft 28 of the stepping motor 27, and a holder 31 is screwed into the male thread 29. A steel ball 32 is interposed between the adjusting screw 26 and the output shaft 28. The nozzle adapter guide 17 and the holder 31 are attached to a case 33 of the gun type burner 2, and a fan 34 is attached to the case 33. A servo motor 35 and a damper 36 are attached to the fan 34, and the damper 36 is driven by the servo motor 35. An output end of the control device 10 is connected to a stepping motor 27 and a servo motor 35. Servo motor 35
is driven by the control device 10 in conjunction with the stepping motor 27. Although not shown, the output shaft 28 of the stepping motor 27 is limited to reciprocating rotation within a predetermined angle range smaller than 360 degrees, and two detectors connected to the control device 10 serve as detectors for the output shaft 28 of the stepping motor 27. A limit switch is provided. Further, the rotation angle of the output shaft of the servo motor 35 that drives the damper 36 is detected by a potentiometer connected to the control device 10.

The control device 10 controls the stepping motor 2.
7 is driven, the output shaft 28 rotates, thereby moving the output shaft 28 in the axial direction. Since the nozzle adapter 13 is pressed against the output shaft 28 by the coil spring 23 via the flange 22, adjustment screw 26, and steel ball 32,
The nozzle adapter 13 and the nozzle 14 move together with the output shaft 28, and the distance between the injection port 15 of the nozzle 14 and the shielding plate 18 changes. As a result, the amount of fuel that passes through the hole 19 of the shielding plate 18 among the fuel ejected from the injection port 15 of the nozzle 14 changes, and the amount of combustion changes. Note that the fuel is supplied to the injection port 15 of the nozzle 14 via the fuel pipe 16 at a predetermined pressure that provides a good atomization state by a fuel pump (not shown), and the fuel is supplied to the injection port 15 of the nozzle 14 through the fuel pipe 16 without passing through the hole 19 of the shielding plate 18. The captured fuel is recovered through the recovery pipe 21. on the other hand,
When the servo motor 35 is driven by the control device 10,
The damper 36 rotates, and the amount of air sucked into the fan 34, ie, the amount of air for combustion, changes. The opening degree of the damper 36 is determined in advance according to the combustion amount, is detected by a potentiometer, and is fed back to the control device 10.

FIG. 3 is a front view of the operating section of the control device 10.
A push button switch 38 and an indicator light 39 consisting of a light emitting diode are installed in the operation section of the control device 10 for initial adjustment of the gun type burner 2.

Next, the initial adjustment work of the gun type burner 2 will be explained with reference to FIG. Figure 4 shows nozzle 1
4 is an explanatory diagram of the relationship between the combustion amount and the opening degree of the damper 36, where the horizontal axis represents the number of steps of the stepping motor 27,
The vertical axis represents the combustion amount and the opening degree of the damper 36. Further, the solid line A is the combustion amount, and the dashed line B is the opening degree of the damper 36. First, the operator sets the nozzle 14 at an appropriate position,
After setting the stepping motor 27 to the reference position, that is, the position where the number of steps is 0, the push button switch 38 of the control device 10 is operated. As a result, the control device 10 enters the initial adjustment mode, and the control device 10 controls the flow rate adjustment valve 9, the stepping motor 27, the fan motor of the fan 34, and the servo motor 3.
An output signal is supplied to 5 and 5. As a result, the flow rate adjustment valve 9
is fully open, and the output shaft 2 of the stepping motor 27
8 rotates by a first predetermined number of steps A, the nozzle 14 moves, the fan motor of the fan 34 rotates, and the output shaft of the servo motor 35 rotates by an angle corresponding to the number of steps A. Then, the damper 36 reaches the opening degree α. When the output shaft 28 of the stepping motor 27 rotates by the number of steps A and stops, the control device 10 starts the fuel pump and causes the ignition rod 20 to generate a spark, starting combustion. At this time, due to variations in the characteristics of the individual nozzles 14, the combustion amount often does not reach the combustion amount a, which is the first predetermined combustion amount. Therefore, next, the operator manually operates the adjusting screw 26 to move the nozzle 14 to adjust the combustion amount to a. At this time, the control device 10 controls the hot water temperature detector 8
Monitor the detection signal from the
Turn on 9. When the combustion amount reaches a, the control device 10 drives the stepping motor 27 and adjusts the combustion amount to the second predetermined combustion amount b by feedforward and feedback control. At this time, the servo motor 35 is driven by the control device 10 together with the stepping motor 27, and the opening degree of the damper 36 becomes β. Then, the control device 10 stores the number of steps B-A of the stepping motor 27 required to change the combustion amount from a to b in a memory (not shown).

By the above operations, the combustion amount a is changed from the combustion amount b.
The number of steps B-A of the stepping motor 27 taken to reach the point B-A is known, and from this, the slope of the solid line A in FIG. 4 can be determined. Therefore, during feedforward control in subsequent normal operation, the control device 10 controls the stepping motor 27 according to the target combustion amount based on B-A stored in the memory.
Control is performed by calculating the number of steps. Therefore, only a small amount of control is required by feedback, and control responsiveness is improved. Furthermore, if the servo motor 35 is driven according to the number of steps of the stepping motor 27 as in this embodiment, the amount of combustion air is controlled according to the combustion amount, resulting in an unstable combustion state during the transition period. Never. Furthermore, compared to the case where the position of the nozzle 14 is detected by a detector and the opening degree of the damper 36 is controlled, the structure is simpler and the manufacturing cost is lower.

Although only one combustion amount b, which is the second predetermined combustion amount, is set in the above embodiment, for example, the combustion amount b1
, b2 , b3 the number of steps B1 −A, B2
-A, B3 -A may be obtained and stored in memory. By increasing the number of measurement points in this way, more accurate control can be achieved. Further, in the above embodiment, the reference position is set to the position where the number of steps of the stepping motor 27 is 0, but the reference position may be set to the position where the number of steps is maximum. Further, in the above embodiment, the amount of combustion air is adjusted by the damper 36, but the rotation speed of the fan motor may also be controlled. Further, it is preferable that the memory of the control device 10 be backed up by a battery, or use an EEPROM or the like in case of a power outage or the like. Note that the above initial adjustment method is not limited to before shipping or when replacing the nozzle 14, but may be performed as appropriate, for example, at every predetermined usage time or number of times of use.

[0015]

Effects of the Invention The present invention has the above-described configuration, and the stepping motor is driven by the first predetermined number of steps from the reference position by the control device, and in this state, the amount of fuel burned becomes the first predetermined amount of combustion. In the first step, the position of the nozzle is manually adjusted, and the stepping motor is driven by the control device so that the amount of fuel burned becomes a second predetermined combustion amount, and the control device stores the number of steps at this time. the action,
A second process performed for at least one type of second predetermined combustion amount.
Since the relationship between the nozzle position and the combustion amount can be accurately detected, the feedforward control amount can be calculated appropriately during subsequent normal operation, and combustion control can be performed satisfactorily. In addition, in the first stroke, the position of the nozzle is manually adjusted so that the amount of fuel burned becomes the first predetermined combustion amount, so the movement range of the nozzle by the stepping motor accurately matches the desired combustion amount adjustment range. It is possible to achieve accurate combustion control.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a gun-type burner adjusted by an initial adjustment method in an embodiment of the present invention.

FIG. 2 is a schematic overall configuration diagram of a water heater equipped with a gun-type burner adjusted by an initial adjustment method in an embodiment of the present invention.

FIG. 3 is a front view of the operating section of the control device.

FIG. 4 is an explanatory diagram of the relationship between the nozzle position, combustion amount, and damper opening degree.

FIG. 5 is an explanatory diagram of variations in burner characteristics.

[Explanation of symbols]

2 Gun type burner 10 Control device 14 Nozzle 18 Shielding plate 19 hole 27 Stepping motor

Claims (1)

[Claims] 1. A shielding plate having a hole, a nozzle that can manually adjust the distance between the shielding plate and injecting fuel, and a stepping motor that moves the nozzle to change the distance between the nozzle and the shielding plate. A gun type configured to include a control device that drives the stepping motor, and to control the combustion amount by changing the distance between the shielding plate and the nozzle to change the amount of fuel passing through the hole of the shielding plate. When initially adjusting the burner, the stepping motor is driven by a first predetermined number of steps from the reference position by the control device, and in this state, the nozzle is positioned so that the amount of fuel burned becomes the first predetermined amount. a first step in which the stepping motor is manually adjusted; and an operation in which the control device drives the stepping motor so that the amount of fuel burned becomes a second predetermined combustion amount, and the control device stores the number of steps at this time. and a second stroke performed for at least one kind of the second predetermined combustion amount.