JPH01189417A - Post-purge controller for combustor - Google Patents

Abstract

PURPOSE:To avoid generating the feeling of a cold air flow at the time of post-purge and prevent a combustor body from being overheated, by providing a maximum discriminating part for determining an upper limit for an integrating timer, and a minimum discriminating part for determining a lower limit for the integrating timer for the case where an operating switch is again turned ON after being once turned OFF. CONSTITUTION:A combustion timer 32 counts combustion time, and a calculating part 33 calculates a timer value for the combustion time. An integrating timer 34 determines a post-purge period based on the timer value sent from the calculating part 33, a period of time for which the timer 34 itself outputs a signal to a fan motor controlling part 29, and a calculated value stored when an operating switch 23 was turned ON in the preceding post-purge, and continues outputting an operating signal to the controlling part 29 for the post-purge period even when the switch 23 is turned OFF. A maximum discriminating part 35 determines an upper limit for the timer 34, whereas a minimum discriminating part 36 determines a lower limit for the timer 34 for the case where the switch 23 is again turned ON after being once turned OFF.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to combustion devices in various fields, mainly heaters and water heaters that use gas, oil, etc. as fuel and perform combustion.

Conventional technology In recent years, with the introduction of electronic technology such as microcomputers, post-purge control devices for combustion equipment have changed from conventional devices that detect the body temperature using bimetallic switches and perform post-purge control to internal control devices such as microcomputers. There is a shift to a control system in which post-purge is performed for a certain period of time using a timer, and post-purge control using electronic technology such as a microcomputer is becoming more important.

An example of the conventional post-purge control device for the above-mentioned combustion equipment will be described below with reference to the drawings.

FIG. 3 shows a block diagram of a conventional post-purge control device for combustion equipment. In FIG. 3, 1 is an outlet. 2 is a fan for blowing air. 3 is a fan motor drive unit), which drives the ventilation fan 2. 4 is a transformer, 06 is a rectifier, o6 which performs full-wave rectification of the AC power supply is a smoothing capacitor, and o7 which smoothes the DC power obtained by the rectifier 5 is a resistor.

Reference numeral 8 denotes an operation switch, and 09, which turns the appliance on and off, is a determination section, which determines and controls the operation of the appliance based on the signal from the operation switch 8. Reference numeral 1o denotes a combustion control section, which performs combustion control based on a signal from an operation switch 8. A fan motor control section 11 outputs a control signal to the fan motor drive section 3. A delay timer 12 outputs a signal to operate the fan motor control unit 11 for a certain period of time after the operation switch 8 is turned off. The determination unit 9 is the combustion control unit 1
0, fan motor control section 11. It consists of a delay timer 12. 13 is an igniter. Reference numeral 14 denotes a solenoid valve that turns on and off the supply of fuel in response to a signal from the combustion control section 10. 16
is a burner and performs combustion.

The operation of the combustion equipment post-purge control device configured as described above will be described below.

First, commercial power obtained through the outlet 1 is stepped down by the transformer 4, full-wave rectified by the rectifier 4, and then smoothed by the smoothing capacitor 6 to become direct current. The control described later is performed using the DC power source obtained by the above method. When the operation switch 8 is turned on, a signal is sent to the combustion control section 1o and the fan motor control section 11, and the igniter 13. When the solenoid valve 14 is operated and combustion is started by the burner 16, combustion air is obtained by operating the fan motor drive section 3 and driving the ventilation fan 2. The combustion control unit 1° receives the off signal from the operation switch 8 and stops the solenoid valve 14 to stop combustion. When the operation switch 8 is turned off, the delay timer 12 outputs an operation signal to the fan motor control section 11, causing the ventilation fan 2 to rotate for a certain period of time even though the operation switch 8 is turned off. Prevents abnormal heating.

Problems to be Solved by the Invention However, in the above configuration, the delay timer 12 operates only by turning on and off the operation switch 8, and the blowing fan 2 operates regardless of whether or not the vessel is heated or the appliance is combusted. As a result, cold air is emitted from the appliance, which has the problem of reducing the feeling of use, especially in heaters, due to the feeling of cold air.

In view of the above problems, the present invention provides a post-purge control device that does not give a feeling of cold air during post-purge, and also prevents the vessel from overheating, which is the original purpose.

Means for Solving the Problems In order to solve the above problems, the post-purge control device for a combustion appliance according to the present invention includes an operation switch that turns on and off the operation of the appliance, and a system that determines the on/off signal of the operation switch and controls each part. a determination unit that controls, a solenoid valve that turns on and off the supply of fuel in response to a combustion control signal from the determination unit, an igniter that ignites the fuel, and a 71 engine motor that operates in response to a fan motor control signal from the determination unit. A burner that performs combustion when the electromagnetic valve and the igniter operate, a combustion sensor that converts a flame signal in the burner into an electric signal and transmits it to the determination section, and a fan motor drive section that blows air. a combustion control section that operates in response to an input signal from the operation switch and outputs a combustion control signal; a combustion detection section that detects the presence or absence of combustion based on the electric signal of the combustion sensor; a combustion timer that counts the time when combustion is determined to be present by the combustion detection section; A calculation unit that calculates the time obtained by the timer and sets a timer length suitable for the appliance; and a calculation unit that adds the timer length calculated by the calculation unit and outputs a signal to the fan motor control unit by itself. When the operation switch is turned off, the operation signal is output to the fan motor control section, the time during which the fan motor control section outputs its own signal, and the previous calculated value. Output until the storage time and result are less than or equal to -a certain value. Alternatively, a calculation timer that stops the operation signal to the fan motor control section and stores the calculation value at that time when the operation switch is turned on before the calculation value becomes equal to or less than a certain value, and a calculation timer that stores the calculation value at that time; a maximum value determination unit that determines the upper limit value of the integration timer; and a minimum value determination unit that determines the lower limit value of the integration timer when the operation switch is turned on again after the operation switch is turned off. The device has a configuration including a timer section.

Function The present invention detects the combustion time using the above-described configuration, and calculates the time length for which the combustion time is calculated, the time length for which the integration timer outputs its own signal to the fan motor control section, and the previous time. By turning on the operation switch during post-purge, the calculated value with the memorized time length is set as the post-purge time, and the maximum value of the calculated value and the above-mentioned operation again after the operation switch is turned off are set as the post-purge time. Since the minimum value when the switch is turned on is determined, a post purge time that matches the combustion time can be obtained, there is no feeling of cold air, and there is no need to repeat the operation of combustion and turning off the operation switch. This means that abnormal heating of the vessel body can be prevented even in the event of malicious operation.

EXAMPLE Hereinafter, a post-purge control device for a combustion equipment according to an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a block diagram of a post-purge control device for a combustion device in an embodiment of the present invention. In FIG. 1, 16 is an outlet.

17 is a fan for blowing air. A fan motor drive section 18 drives the ventilation fan 17. 1e is a transformer. 20 is a rectifier which performs full-wave rectification of the AC power source. A smoothing capacitor 21 smoothes the DC power obtained by the rectifier 2o. 22 is a resistance. Reference numeral 23 is an operation switch for turning on and off the appliance. Reference numeral 24 denotes a determination section, which determines and controls the operation of the device based on the signal from the operation switch 23. A combustion control section 26 performs combustion control in response to a signal from the operation switch 23. 2
6 is an igniter. 27 is a solenoid valve.

The igniter 26 and the electromagnetic valve 27 are controlled by signals from the combustion control section 26. 28 is a burner that performs combustion. Reference numeral 29 denotes a fan motor control section, which controls the air blower 77 via the fan motor and drive section 18. 30 is a combustion sensor that exchanges a flame signal into an electrical signal; 31 is a combustion detection section that detects combustion based on the electrical signal obtained by the combustion sensor 30. 32 is a combustion timer that counts combustion time. 33 is a calculation unit that calculates a timer value for the combustion time. 34 is an integration timer, which calculates the timer value from the calculation unit 33, the time during which the integration timer 34 outputs its own signal to the fan motor control unit 19, and the time when the operation switch 23 was turned on during the previous post-purge. Accordingly, the post-purge time is determined based on the stored calculated value at that time, and even if the operation switch 23 is turned off, an operation signal is output to the fan motor control 29 during the post-purge time.

36 is a maximum value determination section, which determines the upper limit value of the integration timer 34. 36 is a minimum value determination section, and an operation switch 23
After the operation switch is turned off, the lower limit value of the integration timer 34 is determined when the operation switch is turned on again. 37 is a delay timer section, which includes an integration timer 34 and a maximum value determination section 3.
5 and a minimum value determination section 36, and the determination section 24 is composed of a combustion detection section 26.5 and a minimum value determination section 36. Fan motor control section 29. Combustion detection section 31. Combustion timer 32. Arithmetic unit 33. The delay timer 37 is also provided.

The operation of the combustion equipment post-purge control device configured as described above will be described below with reference to FIGS. 1 and 2.

First, FIG. 2 shows changes in the cumulative timer length over time. Commercial power is taken into the circuit via the outlet 16, stepped down by the transformer 19, and then passed through the rectifier 2o.
After full-wave rectification, the current is smoothed by a smoothing capacitor 21 to become direct current.

The smoothed direct current thus obtained is subjected to multi-control. When the operation switch 23 is turned on, the combustion control section 2
5 and the fan motor control unit 29, respectively.
Igniter 26. The electromagnetic valve 27 is operated to cause the burner 28 to start combustion.

Alternatively, the fan motor drive section 18 is operated to drive the ventilation fan 17. The burning signal is converted into a gas signal by the combustion sensor 3o, and the signal is sent to the combustion detection section 31. The combustion detection unit 31 outputs an electric signal from the combustion sensor 31 to the combustion timer 32 only when determining combustion, and causes the combustion time to be counted. The calculation unit 33 calculates the value of the combustion timer 32. The integration timer 34 will be explained according to FIG.

First, the elapsed time t. -t20 is a state in which the combustion sensor 3o detects a combustion signal, passes through the combustion timer 32, and then adds a value reversely calculated by the calculation unit 33 to the integration timer 34. At the elapsed time t0, the lower limit value PTf determined by the minimum value determination unit 36! 1 is given to the integration timer 34, and at tl, the maximum value determination section 35 limits the upper limit of the integration timer length to PTM. When the operation switch 23 is turned off at t2, the elapsed time t2 to t
3, the fan motor control unit 29
The operation signal is outputted to , and at the same time, it is subtracted from the integration timer 34. When the operation switch 23 is turned on again at t3, the cumulative timer length PT1 at that time is compared with the lower limit determined by the minimum value determination section 36, and PTm≧PT.
Since it is 1, PTtn is given as the cumulative timer length. At the same time, the operation signal to the fan motor control section 19 is stopped. During the elapsed time period t3 to t4, the combustion signal is detected again and is added to the cumulative timer length PTm in the same manner as described above. When the operation switch 23 is turned off again at t4, an operation signal is output to the fan motor control unit 29 and subtracted from the integration timer 34 during the elapsed time to t6, as described above.

At t6, if the operation switch is set to the third layer human state, the cumulative timer length at that time is compared with the lower limit determined by the T2 minimum value determination unit 36, and since PTm<PT2, PT2 is maintained as the cumulative timer length. dripping

At the same time, the operation signal to the fan motor control section 19 is stopped. During the elapsed time period t6 to t6, the three-layer combustion signal is detected and is added to the cumulative timer length PT2 in the same manner as described above. In step 70, when the three-layer operation switch 23 is turned off, during the elapsed time t6 to t7, the operation is performed in the same manner as described above.
While outputting the operation signal to the fan motor control unit 29, the integration timer 34 continues to be subtracted, and the integration timer length is PT.
This continues until o. While the integration timer 34 is outputting an operation signal to the fan motor control section 29, the blower fan 17 continues to rotate even though the operation switch 23 is turned off, and the post-purge operation is now started.

As described above, according to this embodiment, there is a combustion sensor 3o that converts a flame signal into an electrical signal, a combustion detection unit 32 that burns in response to an electrical signal from the combustion sensor 3°, and a combustion timer that counts the combustion time. 32, a calculation unit 33 that calculates a timer value based on the combustion time, the timer value from the calculation unit 33, the time during which the signal is output to the fan motor control unit 19 during the post-purge operation, and the time during the previous post-purge operation. By providing an integration timer 34 that determines the post-purge time based on the calculated value stored when the operation switch 23 is turned on, and a maximum value determination section 35 that limits the upper limit of the integration timer 34, it is possible to This can prevent the feeling of cold air and abnormal heating of equipment.

Effects of the Invention As described above, the present invention includes an operation switch that turns on and off the operation of the appliance, a determination section that determines the on/off signal of the operation switch and controls each part, and a fuel supply system that uses the combustion control signal from the determination section. A solenoid valve that turns on and off the fuel, an igniter that ignites the fuel, a fan motor drive section that also operates based on the fan motor control signal from the determination section, and the solenoid valve and the igniter that cause combustion to occur during operation. a combustion sensor that converts a flame signal in the burner into an electric signal and transmits it to a determination section; and a blowing fan that blows air controlled by the fan motor drive section, and the determination section includes:
A combustion control section that operates according to an input signal of the operation switch and outputs a combustion control signal, a fan motor control section that outputs an output to the fan motor drive section according to an input signal of the operation switch, and an electric signal of the combustion sensor. , a combustion detection unit that detects the presence or absence of combustion, and a combustion timer that counts the time when combustion is determined to be present by the combustion detection unit;
A calculation unit that calculates the time obtained by the combustion timer and sets the timer length to a timer length suitable for the appliance; and a calculation unit that adds the timer length calculated by the calculation unit and outputs a signal to the fan motor control unit by itself. When the operation switch is turned off, it outputs an operation signal to the fan motor control section, and subtracts the time during which it outputs its own signal to the fan motor control section, and the previous time. The output is performed until the result of the calculated value and the storage time becomes less than or equal to a certain value. Alternatively, an integration timer that stops the operation signal to the fan motor control section when the operation switch is turned on before the calculation value becomes equal to or less than a certain value, and stores the calculation value at that time; a maximum value determination unit that determines the upper limit value of the integration timer; and a minimum value determination unit that determines the lower limit value of the integration timer when the operation switch is turned on again after the operation switch is turned off. By providing a timer section, the blower fan can be prevented from operating regardless of whether or not the appliance is burning, and cold air will not be emitted from the appliance.

Particularly in a heater, a good post-purge experience can be obtained.

Moreover, heating of the vessel body can be prevented even if the operation is performed maliciously, such as repeating combustion and turning off the operation switch.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a post-purge control device for a combustion device in an embodiment of the present invention, FIG. 2 is a diagram showing changes in the integration timer length over time in an embodiment of the present invention, FIG. 3 is a block diagram of a post-purge control device for a combustion device in a conventional embodiment. 17...Blower fan, 23...Operation switch, 24...Judgment unit, 26...
Igniter, 27... Solenoid valve, 28... Burner, 30... Combustion sensor, K7...
Delay timer section. Name of agent: Patent attorney Toshio Nakao and one other person +
Ambiguous”JヱUj= 8

Claims (1)

[Claims] An operation switch that turns on and off the operation of the appliance, a determination unit that determines the on/off signal of the operation switch and controls each part, an electromagnetic valve that turns on and off the supply of fuel based on the combustion control signal from the determination unit, and the fuel. a fan motor drive unit that also operates based on a fan motor control signal from the determination unit; a burner that performs combustion when the electromagnetic valve and the igniter operate; and a flame signal in the burner. a combustion sensor that converts the signal into an electrical signal and transmits it to a determination section;
and a blowing fan that blows air under the control of the fan motor drive section, and the determination section operates in response to an input signal of the operation switch and outputs a combustion control signal, and the determination section also includes a combustion control section that outputs a combustion control signal, and a combustion control section that operates in response to an input signal of the operation switch. A fan motor control unit that outputs an output to the fan motor drive unit based on an input signal, a combustion detection unit that detects the presence or absence of combustion based on an electric signal from the combustion sensor, and a time period during which combustion is determined to be present by the combustion detection unit is counted. a combustion timer that calculates the time obtained by the combustion timer, a calculation unit that calculates the time obtained by the combustion timer to a timer length suitable for the appliance, and adds the timer length calculated by the calculation unit,
The fan motor control section has a function of subtracting the time during which the signal is outputted by itself, and when the operation switch is turned off, an operation signal is sent to the fan motor control section.
The signal is output until the result of the time during which it outputs the signal to the fan motor control section and the storage time of the previous calculated value becomes less than a certain value, or until the calculated value becomes less than the certain value. an integration timer that stops the operation signal to the fan motor control unit when the operation switch is turned on and stores the calculated value at that time; a maximum value determination unit that determines an upper limit value of the integration timer; A post-purge control device for a combustion appliance, comprising a delay timer section having a minimum value determination section that determines a lower limit value of the integration timer when the operation switch is turned on again after the switch is turned off.