JP2646607B2 - Post-purge control device for combustion equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion device in various fields, mainly a heater and a water heater that perform combustion by using gas or petroleum as fuel.

2. Description of the Related Art In recent years, post-purge control devices for combustion appliances have been changed from internal devices such as microcomputers to internal post-purge control devices that detect the body temperature with a bimetal switch and perform post-purge control. Therefore, the control method is shifting to a control method in which post-purge is performed only for a certain period of time, and post-purge control using electronic technology such as a microcomputer is regarded as important.

Hereinafter, an example of the above-described conventional post-purge control apparatus for a combustion appliance will be described with reference to the drawings.

FIG. 3 is a block diagram showing a conventional post-purge control device for a combustion appliance. In FIG. 3, reference numeral 1 denotes an outlet. 2 is a fan for blowing. Reference numeral 3 denotes a fan motor drive unit that drives the blower fan 2. 4 is a transformer. Reference numeral 5 denotes a rectifier, which rectifies full-wave AC power. Reference numeral 6 denotes a smoothing capacitor for smoothing the DC power obtained by the rectifier 5. 7 is a resistor. Reference numeral 8 denotes an operation switch for turning on / off the device. 9
Is a determination unit, which determines and controls the operation of the appliance based on the signal of the operation switch 8. Reference numeral 10 denotes a combustion control unit which performs combustion control according to a signal from the operation switch 8. Reference numeral 11 denotes a fan motor control unit that outputs a control signal to the fan motor drive unit 3. Reference numeral 12 denotes a delay timer, which outputs a signal for operating the fan motor control unit 11 for a fixed time after the operation switch 8 is turned off. The determination unit 9 includes a combustion control unit 10, a fan motor control unit 11, and a delay timer 12. 1
3 is an igniter. Numeral 14 denotes an electromagnetic valve which turns on and off the supply of fuel in response to a signal from the combustion control unit 10. 15 is a burner which burns.

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

First, the commercial power obtained through the outlet 1 is stepped down by the transformer 4, full-wave rectified by the rectifier 4, and then converted into a direct current which is smoothed by the smoothing capacitor 6. The following control 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 unit 10 and the fan motor control unit 11, and the igniter 13 and the solenoid valve 1 are respectively transmitted.
The combustion air is obtained by operating the fan motor drive unit 3 and driving the blower fan 2 while starting combustion by the burner 15. Next, operation switch 8
Is turned off, the combustion control unit 10 receives the turn-off signal of the operation switch 8, stops the solenoid valve 14, and stops the combustion. Then, when the operation switch 8 is turned off, the delay timer 12 outputs an operation signal to the fan motor control unit 11 and rotates the blower fan 2 for a certain period of time despite the operation switch 8 being turned off,
Abnormal heating of the body is prevented.

However, in the above configuration, the operation switch 8
The delay timer 12 operates only by turning on and off, and the blower fan 2 operates irrespective of the presence or absence of heating of the body or the burning of the appliance. There was a problem of reducing the usability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a post-purge control device that does not give a feeling of cool air during post-purge and that prevents the overheating of the container, which is the original purpose.

Means for Solving the Problems In order to solve the above problems, a post-purge control apparatus for a combustion appliance according to the present invention controls an operation switch for turning on and off the operation of the appliance and an on / off signal of the operation switch to control each unit. And a solenoid valve for turning on and off the supply of fuel according to a combustion control signal from the determination unit, an igniter for igniting the fuel, and a fan motor driven by a fan motor control signal from the determination unit Unit, a burner that performs combustion when the solenoid valve and the igniter operate, a combustion sensor that transmits a flame signal in the burner as an electric signal to a determination unit, and an air blower that is controlled by the fan motor drive unit and blows air. A combustion control unit that operates according to an ON signal of the operation switch and outputs a combustion control signal. A fan motor control unit that outputs a signal to the fan motor drive unit, a combustion detection unit that detects the presence or absence of combustion based on an electric signal of the combustion sensor, and counts time when the combustion detection unit determines that there is combustion. A combustion timer that calculates the time obtained by the combustion timer, adds a timer length calculated by the calculation unit to a timer length suitable for the calculation time, and adds the timer length calculated by the calculation unit to the fan motor control unit. Has a function of subtracting the time during which the signal itself is being output, and when the operation switch is turned off, outputs an operation signal to the fan motor control unit, and outputs a signal to the fan motor control unit itself. Output until the result of the stored time and the storage time of the previous calculated value become equal to or less than a certain value. Alternatively, when the operation switch is turned on until the operation value becomes equal to or less than a predetermined value, an operation signal to the fan motor control unit is stopped, and an integration timer for storing the operation value at that time; A maximum value determination unit that determines the upper limit of the, 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, A delay timer unit for outputting a timer length time of a timer value of the integrating timer and outputting the timer value is provided.

Action The present invention detects the combustion time by the above-described configuration,
The length of time during which the combustion time was calculated, the length of time during which the integration timer outputs its own signal to the fan motor control unit,
By turning the operation switch on during the previous post-purge, the post-purge time is calculated using the calculated value with the stored time length, and the maximum value of the calculation value and again after the operation switch is turned off. Since the minimum value when the operation switch is turned on is determined, a post-purge time according to the combustion time is obtained, and there is no feeling of cool wind,
In addition, abnormal heating of the body can be prevented even for a mean operation such as repeating the operation of burning and turning off the operation switch.

Embodiment Hereinafter, a post-purge control device for a combustion apparatus according to an embodiment of the present invention will be described with reference to the drawings. Figure 1
FIG. 2 is a block diagram of a post-purge control device for a combustion apparatus according to an embodiment of the present invention. In FIG. 1, 16
Is an outlet. 17 is a fan for blowing air. Reference numeral 18 denotes a fan motor drive unit that drives the blower fan 17.
19 is a transformer. Reference numeral 20 denotes a rectifier, which performs full-wave rectification on the AC power supply. 21 is a smoothing capacitor, a rectifier
The DC power supply obtained in step 20 is smoothed. 22 is a resistor. Reference numeral 23 denotes an operation switch for turning on / off the device. Reference numeral 24 denotes a determination unit that determines and controls the operation of the appliance based on a signal from the operation switch 23. Reference numeral 25 denotes a combustion control unit which performs combustion control in accordance with a signal from the operation switch 23. 26 is an igniter. 27 is a solenoid valve. The igniter 26 and the solenoid valve 27 are controlled by a signal from the combustion control unit 25. Reference numeral 28 denotes a burner that performs combustion. Reference numeral 29 denotes a fan motor control unit which controls the blower fan 17 via a fan motor drive unit 18. A combustion sensor 30 converts a flame signal into an electric signal. Reference numeral 31 denotes a combustion detecting unit which detects combustion by an electric signal obtained by the combustion sensor 30. 32 is a combustion timer which counts the combustion time. Reference numeral 33 denotes a calculation unit which calculates a timer value for the combustion time. Numeral 34 is an integrating timer, the timer value from the calculating unit 33, the time during which the integrating timer 34 outputs its own signal to the fan motor control unit 19, and the operation switch 23 is turned on during the previous post-purge. Accordingly, the post-purge time is determined based on the stored calculated value at that time, and an operation signal is output to the fan motor control 29 during the post-purge time even if the operation switch 23 is turned off. Reference numeral 35 denotes a maximum value judging unit which determines an upper limit value of the integration timer 34.
Numeral 36 denotes a minimum value judging unit which determines the lower limit value of the integration timer 34 when the operation switch 23 is turned on again after the operation switch 23 is turned off. Reference numeral 37 denotes a delay timer unit, which includes an integration timer 34, a maximum value determination unit 35, and a minimum value determination unit.
The determination unit 24 includes a combustion detection unit 25,
It includes a fan motor control unit 29, a combustion detection unit 31, a combustion timer 32, a calculation unit 33, and a delay timer 37.

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

First, FIG. 2 shows the change of the integration timer length with the passage of time. The commercial power is taken into the circuit via the outlet 16, is stepped down by the transformer 19, is full-wave rectified by the rectifier 20, and is smoothed by the smoothing capacitor 21 to be DC. Control is performed by the smoothed direct current obtained in this manner. When the operation switch 23 is turned on, a signal is sent to the combustion control unit 25 and the fan motor control unit 29 to operate the igniter 26 and the solenoid valve 27, respectively, and the burner 2
Start combustion with 8. Alternatively, the fan motor drive unit 18 is operated to drive the blower fan 17. The combustion state is converted into an electric signal by the combustion sensor 30,
It is sent to the combustion detection unit 31. The combustion detection unit 31 outputs to the combustion timer 32 only at the time of combustion determination based on the electric signal from the combustion sensor 31, and counts the combustion time. The calculation unit 33 calculates the value of the combustion timer 32. The integration timer 34 will be described with reference to FIG. First, during the elapsed time t _{0 to} t ₂ , the combustion sensor 30 detects the combustion signal, and after passing through the combustion timer 32, the value calculated by the calculation unit 33 is added to the integration timer 34. At the elapsed time t ₀ , the lower limit value P _Tm determined by the minimum value determination unit 36 is given to the integration timer 34, and at t ₁ , the maximum value determination unit 35 sets the upper limit of the integration timer length.
Limited to _PTM . If you turn off the operation switch 23 at t _2, during the elapsed time t ₂ ~t ₃ outputs the operation signal to the fan motor controller 29 from integrating timer 34, is subtracted from the integrated timer 34. operation switch in t ₃
If 23 is turned on again, the accumulated timer length P
_T1 is compared with the lower limit value determined by the minimum value determination unit 36,
Since P _Tm ≧ P _T1 , P _Tm is given as the integration timer length. At the same time, the operation signal to the fan motor control unit 19 is stopped. During the elapsed time t ₃ ~t ₄ in a state where the combustion signal is detected again, in the same manner as described above, is added to the integrated timer length P _Tm. If the operation switch 23 again switch in t _4, during the elapsed time t ₄ ~t _5, like the above, is subtracted from the integrated timer 34 outputs an operation signal to the fan motor controller 29. In t _5, if the operation switch three times the input state is compared with the lower limit value determined by integrating timer length P _T2 minimum value determining unit 36 at that time, since it is a P _Tm <P _T2, as the integrated timer length P _T2 is maintained. At the same time, fan motor control unit 1
Stop the operation signal to 9. During the elapsed time t ₅ ~t _6, in a state where three times the combustion signal is detected, in the same manner as described above, is added to the integrated timer length P _T2. In t _6, when the third time the operation switch 23 off, during the elapsed time t ₆ ~t _7, in the same manner as described above, and outputs an operation signal to the fan motor controller 29, subtracted from the integrating timer 34 And the integration timer length
It continues until it reaches P _T0 . While the integration timer 34 outputs an operation signal to the fan motor control unit 29,
17 performs the post-purge operation even though the operation switch 23 is turned off.

As described above, according to the present embodiment, a combustion sensor 30 that converts a flame signal into an electric signal, a combustion detection unit 32 that burns based on the electric signal from the combustion sensor 30, a combustion timer 32 that counts the combustion time, A calculation unit 33 that calculates a timer value based on the combustion time; a timer value from the calculation unit 33; a time during which a signal is output to the fan motor control unit 19 during the post-purge operation; and an operation switch during the previous post-purge. By providing an integration timer 34 that determines the post-purge time based on the calculated value stored when 23 is turned on, and a maximum value determination unit 35 that limits the upper limit of the integration timer 34, And abnormal heating of the appliances can be prevented.

As described above, according to the present invention, the combustion timer calculates the cumulative time from the flame signal of the burner detected by the combustion detecting section, and the calculating section calculates the fuel accumulated in the burner or the like during the combustion by the cumulative burning time. After the combustion is stopped, a length suitable for cooling and radiating the heat by the fan motor is calculated. The integration timer adds the calculation time corresponding to the burner time, subtracts the time of cooling and heat radiation by the blow of the fan motor after stopping the combustion, and outputs until the timer value of the integration timer becomes equal to or less than a certain value. When the operation state is resumed before the timer value becomes equal to or less than the predetermined value, the output is stopped, and the cumulative combustion time calculated by the calculation unit is added again. Then, the addition of a value equal to or greater than a predetermined upper limit value to the maximum value determination unit is stopped. In addition, when adding the cumulative combustion time, if it is less than the lower limit predetermined in the minimum value determination unit, add from the lower limit,
If it is equal to or more than the lower limit value, the addition is performed from the timer value as it is.

By setting the timer length of the timer value of the integration timer to the post-purge time, heat storage of the body such as a burner can be quickly radiated and cooled, and no cool air is generated due to redundant cooling. The sensation during post-purge is obtained. In addition, when the operation state is resumed before the timer value of the integration timer becomes equal to or less than the fixed value, the addition result from the arithmetic unit is added again with a value equal to or more than the lower limit value, thereby repeatedly operating combustion and stopping. Thus, abnormal heating due to a malicious operation, such as a gradual increase in heat storage of a body such as a burner, can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of a post-purge control device for a combustion apparatus according to an embodiment of the present invention. FIG. 2 is a diagram showing a change with time of an integrated timer length in an embodiment of the present invention. FIG. 1 is a block diagram of a post-purge control apparatus for a combustion apparatus according to a conventional embodiment. 17 ... Fan for blower, 23 ... Operation switch, 24 ... Judgment unit, 26 ... Igniter, 27 ... Solenoid valve, 28 ... Burner, 30 ...
... combustion sensor, 37 ... delay timer section.

Claims (1)

(57) [Claims] An operation switch for turning on and off the operation of the appliance, a judgment unit for judging an on / off signal of the operation switch to control each unit, and turning on / off the supply of fuel based on a combustion control signal from the judgment unit. An electromagnetic valve and an igniter that ignites fuel, a fan motor drive unit that also operates according to a fan motor control signal from the determination unit, and a burner that performs combustion when the electromagnetic valve and the igniter operate. The flame signal in the burner is an electric signal, and has a combustion sensor that transmits to a determination unit, and a blower fan that performs blowing by being controlled by the fan motor drive unit. A combustion control unit that operates and outputs a combustion control signal; a fan motor control unit that also outputs to the fan motor drive unit in response to an input signal of the operation switch; A combustion detection unit that detects the presence or absence of combustion, a combustion timer that counts the time when the combustion detection unit determines that there is combustion, and a time obtained by the combustion timer are calculated based on the electric signal of the sensor. An operation unit having a timer length suitable for the operation unit, and a function of adding the timer length calculated by the operation unit, and having the function of subtracting the time during which the fan motor control unit is outputting a signal by itself, the operation switch When the state is turned off, the result of the operation signal to the fan motor control unit, the time of outputting the signal itself to the fan motor control unit, and the storage time of the previous calculated value are less than a certain value. The operation signal to the fan motor control unit is stopped when the operation switch is turned on until the calculated value becomes equal to or less than a predetermined value, and the calculated value at that time is stored. A timer, a maximum value determining unit that determines an upper limit value of the integration timer, and a minimum value determination that determines a lower limit value of the integration timer when the operation switch is turned on again after the operation switch is turned off. And a delay timer unit for outputting a timer length time of a timer value of the integration timer and a delay timer unit for outputting the timer value.