JPH023885B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a spray pressure control device for a nozzle spray burner, and particularly to a nozzle spray burner that automatically removes nozzle clogging, which is the main cause of a drop in hot air temperature. This invention relates to a spray pressure control device.

[Prior Art] Combustion devices include nozzle spray burners that burn highly compressed liquid fuel while spouting it in the form of mist from a spray nozzle. In such a combustion apparatus, for example, an electromagnetic pump is used as a fluid supply means for supplying liquid fuel from a fuel tank to a spray nozzle of a burner. This electromagnetic pump performs a pumping action by reciprocating the electromagnetic plunger.

[Problems to be Solved by the Invention] By the way, in the above-mentioned nozzle spray type burner, as shown in FIG. Needs to be driven. Therefore, the electromagnetic pump is driven and controlled by a control means to maintain a predetermined spray pressure. However, for example, if the spray nozzle is clogged with foreign matter such as dust at the _t2 position and the combustion amount suddenly decreases, the temperature deviation from the target hot air temperature is detected and the phase angle θ is adjusted by Δθ every unit time. Nozzle clogging is removed by reducing the spray pressure and increasing the spray pressure. At this time, if removal is not possible, the phase angle of the electromagnetic pump reaches the minimum phase angle θ ₁ and reaches the maximum spray pressure, without any abnormality being displayed in the state of reduced combustion amount. , combustion was taking place. For this reason, the amount of combustion generated by the burner was insufficient, resulting in the inconvenience that a predetermined performance could not be achieved.

[Object of the Invention] Therefore, in order to eliminate the above-mentioned inconvenience, an object of the present invention is to change the target spray pressure to the maximum spray pressure and the minimum spray pressure when the target hot air temperature has not been reached continuously for a predetermined period of time during drive control. After repeating the pressure and pressure alternately for a predetermined time a predetermined number of times, the fluid supply means is controlled to return to the initial spray pressure, and when the hot air temperature does not reach the target hot air temperature, it is determined that the spray pressure is abnormal and an abnormality is detected. By adopting a control structure that notifies the condition, it actively and automatically removes nozzle clogging, and if removal is not possible, it displays an error in the spray nozzle, achieving smooth drive control of the burner. The object of the present invention is to realize a spray pressure control device for a nozzle spray type burner.

[Means for Solving the Problems] In order to achieve this object, the present invention provides a fluid feeding means for feeding fluid fuel, and the fluid feeding means is controlled from a minimum spray pressure to obtain a minimum spray amount. A control means is provided for controlling drive up to a maximum spray pressure to obtain the maximum spray amount, and the control means drives and controls the fluid feeding means to a predetermined spray pressure to obtain a target hot air temperature which is a target setting spray pressure, If the target hot air temperature has not been reached continuously for a predetermined period of time during drive control, the target setting spray pressure is alternately repeated a predetermined number of times for a predetermined period of time and then the minimum spray pressure, respectively, and then the fluid supply means The spray pressure is controlled to return to the initial spray pressure, and when the hot air temperature does not reach the target hot air temperature, it is determined that the spray pressure is abnormal, and control is performed to notify the abnormal state.

[Function] With the above configuration, if the target hot air temperature is not reached continuously for a predetermined period of time while driving and controlling the fluid supply means at a desired spray pressure, the control means will control the maximum spray pressure and the minimum spray pressure. After repeating the spray pressure alternately for a predetermined time a predetermined number of times, the fluid supply means returns to the initially predetermined spray pressure and continues spraying, and if the target hot air temperature does not return to the target hot air temperature, the control means lowers the spray pressure. It determines that an abnormality is occurring and notifies you of the abnormal condition.

[Examples] Examples of the present invention will be described in detail below based on the drawings.

1 to 6 show embodiments of this invention. In FIG. 1, 2 is a burner mechanism. This burner mechanism 2 has a fuel tank 4, and a fuel passage 6 is communicated with the fuel tank 4. An electromagnetic pump 10 serving as a fluid supply means for supplying fuel to the spray nozzle 8 is interposed in the middle of the fuel passage 6 . This electromagnetic pump 10 performs a pumping action by reciprocating an electromagnetic plunger.
In addition, this electromagnetic pump 10 includes the electromagnetic pump 1
Control means 12 for controlling the operation of 0 is connected.

FIG. 2 shows the configuration of the control means 12. This control means 12 connects an automatic operation operation switch section 14 and a sensor section 16 for detecting hot air temperature to a CPU (Central Processing Unit) 18 consisting of a microcomputer and turns the CPU 18 on and off.
It is connected to a signal section 20, a digital display 22, and an automatic control signal output section 24. Further, the automatic control signal output section 24 is connected to a driver 26, and the driver 26 causes the electromagnetic pump 1 to
0, the first motor 13, and the second motor 13. The control means 12 drives and controls the electromagnetic pump 10 between the lowest spray pressure for obtaining the minimum spray amount and the highest spray pressure for obtaining the largest spray amount, and the hot air temperature remains at the target hot air temperature for a predetermined period of time. If the spray pressure does not reach the minimum spray pressure and the maximum spray pressure, the spray pressure is controlled alternately for a predetermined period of time and repeatedly for a predetermined number of times in accordance with a signal from the CPU 18, so as to repeatedly change the spray pressure from strong to weak.

Further, when the hot air temperature does not reach the target hot air temperature, the control means 12 determines that the spray pressure is abnormal, and performs control to notify the abnormal state by, for example, the digital display section 22.

FIG. 3 shows the waveform of the control characteristic of the control means 12, and each of FIGS. 3a and 3b shows the voltage waveform of phase control, and the frequency of the AC voltage applied to the electromagnetic pump 10 is constant. be. Electromagnetic pump 1
The output voltage to 0 is controlled by the signal from the CPU 18, and FIG. 3a shows the voltage waveform of phase angle control showing the maximum spray pressure, and FIG. 3b shows the phase angle control showing the minimum spray pressure. The control voltage waveforms are shown respectively.

FIG. 4 shows the hot air temperature when the electromagnetic pump 10 is driven and controlled by the CPU 18 so as not to cause a difference between the hot air temperature and the target hot air temperature, with the vertical axis representing the hot air temperature and the horizontal axis representing time. It shows the fluctuating state of.

FIG. 5 shows the electromagnetic pump 10 in FIG.
It shows the phase angle θ during drive control.

Next, the case where the burner mechanism 2 is used as a heat source of a grain dryer by utilizing the characteristics of the control means 12 described above, and the phase angle control will be explained along the flowchart of FIG. 6.

First, when you turn on the operation switch, drying begins and various motors start. Next, the burner drive circuit is activated, turning on the ignition heater and driving the burner fan motor while supplying oil to the burner using the electromagnetic pump, thereby igniting the burner.

Next, the grain moisture value M obtained from a moisture meter (not shown)
2 and the stop moisture set value Ms are compared by a comparison means. When this moisture value M2 reaches the stop moisture value Ms, the burner is extinguished, the various motors are stopped, and the drying is completed.

On the other hand, in the comparison, if the moisture value M2 has not reached the stop moisture value Ms, the detected values from various sensors are input. In other words, the outside air temperature Ta is determined from the outside air temperature sensor, and the outside air humidity is determined from the outside air temperature sensor.
HD, hot air temperature Tb from the hot air temperature sensor, stop moisture value Ms from the stop moisture value setting switch,
The grain amount C is input from the grain amount setting switch, and the grain temperature Tp is input from the grain temperature sensor.

Next, calculate the standard hot air temperature Tc, and calculate the hot air temperature Tc
burner control. Also, the hot air temperature Tb from the hot air temperature sensor is read, and Tc-Tb=T is calculated. Then, it is determined whether T≧Tz (set value) or not, and if NO, it is checked whether the various safety switches are operating, and if there is a problem, it branches and the OK monitor display shows the Displays the message, calls the error handling routine, and performs error handling.

If there is no problem in the safety device operation check, it is determined whether the sampling timer Ts has timed out. If the time has not exceeded, the detected values from various sensors are input. When the sampling timer Ts exceeds, the moisture meter again jumps to determine whether the moisture value M2 has reached a predetermined value.

In the above judgment of T≧Tz, if YES, it is determined whether or not this situation has continued continuously for a preset time (for example, Ta seconds), and if it has not continued, the safety device is activated. Return to the operation confirmation flow. If it continues continuously, set a timer for a predetermined period of time, for example tx seconds,
The control phase angle θ of the electromagnetic pump 10 is set to the maximum phase angle θ ₂ and the electromagnetic pump 10 is set to the minimum spray pressure to obtain the minimum spray amount. Then, it is determined whether tx seconds have elapsed or not, and if NO, the control returns to the maximum phase angle control again, and if YES, the timer is set to a predetermined time, for example, ty seconds. Further, the maximum phase angle θ ₂ is set to the minimum phase angle θ ₁ , and the electromagnetic pump 10 is set to the maximum spray pressure to obtain the maximum spray amount. Then, it is determined whether ty seconds have elapsed or not, and if NO, the control returns to the minimum phase angle control again, and if YES, the counter is incremented by one. Next, it is determined whether the counter is, for example, 2, and if NO, the maximum phase angle control is performed again; if YES, the minimum phase angle θ ₁ is returned to the phase angle θ at which a predetermined spray pressure should be obtained; Read the hot air temperature Tb. Then, calculate Tc−Tb=T, and T
≧Tz (set value), and if NO, it is determined whether the safety device is activated, and the fourth
As shown by the solid line in the figure, the hot air temperature can be raised to the target hot air temperature, and if YES, it is determined that the spray pressure is abnormal, for example, the spray nozzle is clogged, and the digital display etc. A variety of measures are used to indicate whether the spray nozzle is clogged and to determine whether the safety device should be activated.

As a result, if the hot air temperature does not reach the target hot air temperature for a predetermined period of time during grain drying work, the spray pressure can be adjusted to the maximum spray pressure and the minimum spray pressure alternately for a predetermined period of time each predetermined number of times. By changing the strength, it is possible to actively remove clogged spray nozzles.

Further, if the clogging of the spray nozzle cannot be removed, it is possible to display the abnormality of the spray nozzle while continuing the drying operation and notify the operator of the abnormality of the spray nozzle.

[Effects of the Invention] As described in detail above, according to the present invention, when the target hot air temperature has not been reached for a predetermined period of time during drive control, the target spray pressure is set to the maximum spray pressure and the minimum spray pressure, respectively. After alternating and repeating a predetermined number of times for a predetermined time, the fluid supply means is controlled to return to the initial spray pressure, and when the hot air temperature does not reach the target hot air temperature, it is determined that the spray pressure is abnormal and an abnormal state is notified. Since the configuration is configured to control the spray nozzle, if the target hot air temperature does not reach the target hot air temperature continuously for a predetermined period of time, the spray pressure is alternately set to the maximum spray pressure and the minimum spray pressure for a predetermined period of time and is repeated a predetermined number of times to actively prevent clogging of the spray nozzle. It can be removed automatically and achieves smooth drive control of the burner. Further, when the hot air temperature does not reach the target hot air temperature, it can be determined that the spray pressure is abnormal and the abnormal state can be notified, which is advantageous in practice.

[Brief explanation of drawings]

1 to 6 show examples of the present invention, FIG. 1 is a schematic diagram of the burner mechanism, FIG. 2 is a diagram showing the configuration of the control means, and FIGS. 3 a and b are waveforms of control characteristics of the control means. Figure 4 is a diagram showing the relationship between hot air temperature and time, Figure 5 is a diagram showing the relationship between electromagnetic pump phase angle and time, and Figure 6 is a flowchart of the spray pressure control device. . FIG. 7 is a diagram showing the relationship between the phase angle and time of an electromagnetic pump showing the prior art of the present invention. In the figure, 2 is a burner mechanism, 4 is a fuel tank, 6 is a fuel passage, 8 is a spray nozzle, 10 is an electromagnetic pump, 12 is a control means, 16 is a sensor section, 18
is the CPU.

[Claims]

1. A hot air heater that has a hot air outlet 5 in the front part of the main body 1, and a heat exchanger 4 and a blower 3 inside thereof, and blows out heat from the heat exchanger 4 forward by driving the blower 3. The blower 3 is controlled to start and stop by the thermostat 6, and a non-warm air outlet 10 is provided on the upper part of the main body 1 to blow out non-warm air when the blower 8 is driven. Set temperature of 6 to 1
A hot air heater characterized by being provided with a set temperature control means for controlling to lower the temperature by ℃.