A wall-mounted boiler control circuit board and control method thereof

Abstract

A wall-mounted boiler control circuit board and a control method thereof, the control circuit board comprises a control module, a flame detection needle, a flame control circuit and a voltage control circuit, the flame control circuit comprises an amplifying circuit, a voltage reducing circuit, a signal sampling circuit and a signal real-time feedback circuit, the control end of the control module is connected to the input end of the amplifying circuit, the output end of the amplifying circuit is connected to the input end of the voltage reducing circuit, the output end of the voltage reducing circuit is connected to the flame detection needle, the flame detection needle is connected to the signal sampling end of the control module through the signal sampling circuit, the flame detection needle is connected to the signal input end of the control module through the signal real-time feedback circuit, and the voltage control circuit comprises a rectifier circuit, a switch control circuit, an electric energy conversion circuit and a voltage output circuit. The wall-mounted boiler control circuit board of the present invention can judge the flame combustion state, and automatically adjust the fan speed and the opening and closing size of the proportional valve according to the current flame combustion state to control the flame combustion and achieve the purpose of full combustion of fuel.

Description

Technical Field

[0001] The invention relates to the technical field of wall-mounted boilers, and in particular to a wall-mounted boiler control circuit board and a control method thereof. Background Art

[0002] Gas wall-mounted boilers use natural gas, artificial gas or liquefied gas as fuel. The fuel is output through the burner, burned in the combustion chamber, and the heat is absorbed by the heat exchanger. The circulating water in the heating system is heated back and forth when passing through the heat exchanger, thereby continuously outputting heat to the building and providing a heat source for the building. Existing gas wall-mounted boilers generally have the problem of incomplete fuel combustion, which not only wastes energy, but also may produce toxic gases, posing a great safety hazard.

[0003] Therefore, further improvements are necessary. Summary of the invention

[0004] The purpose of the present invention is to provide a wall-mounted boiler control circuit board and a control method thereof which have a simple structure, can fully utilize energy, are highly safe and practical, so as to overcome the shortcomings of the prior art.

[0005] A wall-mounted boiler control circuit board designed for this purpose includes a control module U2, characterized in that it also includes a flame detection pin X1, a flame control circuit and a voltage control circuit, the flame control circuit includes an amplifier circuit, a step-down circuit, a signal sampling circuit and a signal real-time feedback circuit, the control end of the control module U2 is connected to the input end of the amplifier circuit, the output end of the amplifier circuit is connected to the input end of the step-down circuit, the output end of the step-down circuit is connected to the flame detection pin X1, the flame detection pin X1 is connected to the signal sampling end of the control module U2 through the signal sampling circuit, the flame detection pin X1 is connected to the signal input end of the control module U2 through the signal real-time feedback circuit, the voltage control circuit includes a rectifier circuit, a switch control circuit, an electric energy conversion circuit and a voltage output circuit, the input end of the rectifier circuit is connected to the city electricity, the output end of the rectifier circuit is connected to the electric energy conversion circuit, the control end of the switch control circuit is connected to the input end of the electric energy conversion circuit, the output end of the electric energy conversion circuit is connected to the input end of the voltage output circuit, and the output end of the voltage output circuit is connected to the voltage input end of the amplifier circuit.

[0006] The amplifying circuit includes a resistor R15, a transistor Q1, a resistor R90, a resistor R17, a transistor Q2 and a resistor R63. One end of the resistor R15 is connected to the control end of the control module U2, and the other end is connected to the B pole of the transistor Q1. The C pole of the transistor Q1 is connected to the B pole of the transistor Q2 through the resistor R90, and the C pole of the transistor Q2 is grounded through the resistor R63.

[0007] The step-down circuit includes a resistor R283, a coupling capacitor C104 and a resistor R288. One end of the resistor R283 is connected to the C pole of the transistor Q2, and the other end is connected to one end of the coupling capacitor C104. The other end of the coupling capacitor C104 is connected to the flame detection needle X1 through the resistor R288.

[0008] The signal sampling circuit includes a resistor R280, a resistor R281, a resistor R507, a resistor R508, a capacitor C521, a diode D13 and a diode D14. The flame detection needle X1 is connected to the signal sampling end of the control module U2 through the resistor R280 and the resistor R281 in sequence. One end of the resistor R281 is grounded through the capacitor C521 and the resistor R507 connected in parallel. One end of the resistor R281 is connected to the power supply 5V through the resistor R508. One end of the capacitor C521 is connected to the cathode of the diode D14. The flame detection needle X1 is connected to the cathode of the diode D13. The anode of the diode D13 is connected to the anode of the diode D14.

[0009] The signal real-time feedback circuit includes resistor R284, resistor R282, resistor R18, resistor R209, resistor R161 and capacitor C136. The flame detection needle X1 is connected to the signal input end of the control module U2 through resistor R284, resistor R282 and resistor R18 in sequence. One end of the resistor R282 is grounded through the capacitor C136 and resistor R161 connected in parallel, and one end of the resistor R282 is connected to the power supply 5V through the resistor R209.

[0010] The rectifier circuit includes a rectifier bridge D0 and an electrolytic capacitor C51, the electrolytic capacitor C51 is connected in parallel to the output end of the rectifier bridge D0, the power conversion circuit includes a transformer T1, the output end of the rectifier bridge D0 is connected to an input end of the transformer T1, the switch control circuit includes a control chip U1, a diode D21, a resistor R1 and a capacitor C4, the output end of the rectifier bridge D0 is connected to the input end of the control chip U1, and the output end of the control chip U1 is divided into two paths, one path is connected to one input end of the transformer T1 through the diode D21 and the resistor R1 and capacitor C4 connected in parallel, and the other path is connected to the other input end of the transformer T1.

[0011] The voltage output circuit includes a diode D1, an electrolytic capacitor C37, an electrolytic capacitor EC5, a resistor R88, a diode ZD21, a resistor R39, and an optocoupler TLP3. One output end of the transformer T1 is divided into two paths, one path is connected to the E pole of the transistor Q1 and the resistor R17, and the other path is grounded through the electrolytic capacitor C37. The other output end of the transformer T1 is divided into two paths, one path is grounded through the electrolytic capacitor EC5, and the other path is connected to the input end of the optocoupler TLP3 through the resistor R39 and connected to the anode of the diode D1 through the resistor R88. The cathode of the diode D1 is connected to the output end of the transformer T1, the input end of the optocoupler TLP3 is connected to the anode of the diode D1 through the diode ZD21, and the output end of the optocoupler TLP3 is connected to the input end of the control chip U1.

[0012] It also includes a proportional valve control circuit, a signal control circuit, an NTC acquisition circuit, a switching power supply circuit and a fan drive circuit. The control module U2 is respectively connected to the proportional valve control circuit, the signal control circuit, the NTC acquisition circuit, the switching power supply circuit and the fan drive circuit.

[0013] The control module U2 is a single chip microcomputer.

[0014] A control method for a wall-mounted boiler control circuit board designed for this purpose is characterized by comprising the following steps:

[0015] A. The control module U2 outputs a 15HZ square wave which is input to the B pole of transistor Q1 through resistor R15. Transistor Q1 amplifies the square wave signal in reverse. Then the C pole of transistor Q1 outputs the square wave signal and inputs it to the B pole of transistor Q2 through resistor R90.

[0016] B. Transistor Q2 continues to amplify the square wave signal, and then the C pole of transistor Q2 outputs the square wave signal and inputs it to coupling capacitor C104 through resistor R283. Coupling capacitor C104 inputs the square wave signal to flame detection pin X1 through resistor R288, and then flame detection pin X1 detects the flame state;

[0017] C. After the flame detection needle X1 detects the flame state, it outputs the flame signal in three ways. One way is processed by diodes D13 and D14 and then input into the control module U2. One way is sampled by resistors R280 and R281 and then input into the control module U2. One way is fed back to the control module U2 through resistors R284, R282 and R18.

[0018] D. After receiving the feedback signal, the control module U2 automatically adjusts the fan speed and the opening and closing size of the proportional valve to control the flame combustion.

[0019] The wall-mounted boiler control circuit board of the present invention can judge the flame combustion state by setting the flame control circuit and the flame detection needle. After receiving the feedback signal of the flame detection needle, the control module automatically adjusts the fan speed and the opening and closing size of the proportional valve through the flame control circuit, the fan drive circuit and the proportional valve control circuit to control the flame combustion and achieve the purpose of full combustion of the fuel, making the use of the wall-mounted boiler safer and improving the user experience. This control circuit board can also be used to control water heaters. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure is a schematic diagram of the circuit structure of a flame control circuit in one embodiment of the present invention.

[0021] Figure 2 FIG. 4 is a schematic diagram of a circuit structure of a voltage control circuit in an embodiment of the present invention.

[0022] Figure 3 Schematic diagram of the structure of a control circuit board in one embodiment of the present invention. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0024] See also Figure 1-Figure 3 The wall-mounted boiler control circuit board includes a control module U2, a flame detection pin X1, a flame control circuit A and a voltage control circuit B. The flame control circuit A includes an amplifier circuit, a step-down circuit, a signal sampling circuit and a signal real-time feedback circuit. The control end of the control module U2 is connected to the input end of the amplifier circuit, the output end of the amplifier circuit is connected to the input end of the step-down circuit, the output end of the step-down circuit is connected to the flame detection pin X1, the flame detection pin X1 is connected to the signal sampling end of the control module U2 through the signal sampling circuit, the flame detection pin X1 is connected to the signal input end of the control module U2 through the signal real-time feedback circuit, the voltage control circuit B includes a rectifier circuit, a switch control circuit, an electric energy conversion circuit and a voltage output circuit. The input end of the rectifier circuit is connected to the city electricity, the output end of the rectifier circuit is connected to the electric energy conversion circuit, the control end of the switch control circuit is connected to the input end of the electric energy conversion circuit, the output end of the electric energy conversion circuit is connected to the input end of the voltage output circuit, and the output end of the voltage output circuit is connected to the voltage input end of the amplifier circuit. The flame control circuit A detects the flame burning state of the wall-mounted boiler (specifically red flame, blue flame or yellow flame) through the flame detection pin X1. After the flame detection pin X1 detects the flame burning state, it feeds back the variable voltage and current signal (flame signal) to the control module U2 through the signal sampling circuit and the signal real-time feedback circuit. The control module U2 automatically adjusts the fan speed and the opening and closing size of the proportional valve through the flame control circuit A, the fan drive circuit and the proportional valve control circuit according to the current flame burning state to control the air volume and fuel flow rate so that the fuel can be fully burned.

[0025] The amplifier circuit includes a resistor R15, a transistor Q1, a resistor R90, a resistor R17, a transistor Q2 and a resistor R63. One end of the resistor R15 is connected to the control end (pin 2) of the control module U2, and the other end is connected to the B pole of the transistor Q1. The C pole of the transistor Q1 is connected to the B pole of the transistor Q2 through the resistor R90. The C pole of the transistor Q2 is grounded through the resistor R63, and the C pole of the transistor Q1 is grounded.

[0026] The step-down circuit includes a resistor R283, a coupling capacitor C104 and a resistor R288. One end of the resistor R283 is connected to the C pole of the transistor Q2, and the other end is connected to one end of the coupling capacitor C104. The other end of the coupling capacitor C104 is connected to the flame detection needle X1 through the resistor R288. The resistor R283 and the resistor R288 are large-capacity resistors that can reduce the voltage of 220V to 5V, which can improve the safety of the flame detection needle X1 when in use.

[0027] The signal sampling circuit includes resistor R280, resistor R281, resistor R507, resistor R508, capacitor C521, diode D13 and diode D14. The flame detection needle X1 is connected to the signal sampling end (pin 12) of the control module U2 through resistor R280 and resistor R281 in turn. One end of the resistor R281 is grounded through the capacitor C521 and resistor R507 connected in parallel. One end of the resistor R281 is connected to the power supply 5V through the resistor R508. One end of the capacitor C521 is connected to the cathode of the diode D14. The flame detection needle X1 is connected to the cathode of the diode D13, and the anode of the diode D13 is connected to the anode of the diode D14. The signal sampling circuit can sample the variable flame signal and feed the sampled value back to the control module U2, and then the control module U2 processes the sampled value.

[0028] The signal real-time feedback circuit includes resistor R284, resistor R282, resistor R18, resistor R209, resistor R161 and capacitor C136. The flame detection needle X1 is connected to the signal input end of the control module U2 through resistor R284, resistor R282 and resistor R18 in sequence. One end of the resistor R282 is grounded through the capacitor C136 and resistor R161 connected in parallel, and one end of the resistor R282 is connected to the power supply 5V through the resistor R209. The signal real-time feedback circuit feeds back the variable flame signal to the control module U2 in real time, and then the control module U2 processes the flame signal.

[0029] The rectifier circuit includes a rectifier bridge D0 and an electrolytic capacitor C51, the electrolytic capacitor C51 is connected in parallel with the output end of the rectifier bridge D0, the power conversion circuit includes a transformer T1, the transformer T1 is a pulse transformer, the output end of the rectifier bridge D0 is connected to an input end of the transformer T1, the switch control circuit includes a control chip U1, a diode D21, a resistor R1 and a capacitor C4, the output end of the rectifier bridge D0 is connected to pins 1 and 3 of the control chip U1, and is connected to pin 5 of the control chip U1 through a capacitor C45, and the output end (pins 2, 4, 6 and 8) of the control chip U1 is divided into two paths, one path is connected to an input end of the transformer T1 through a diode D21 and a resistor R1 and a capacitor C4 connected in parallel, and the other path is connected to another input end of the transformer T1. The rectifier circuit can rectify the high-voltage alternating current input from the mains power supply into direct current, and the power conversion circuit achieves a stable 220V voltage output under the control of the switch control circuit. The model of the control chip U1 is HEADER.

[0030] The voltage output circuit includes a diode D1, an electrolytic capacitor C37, an electrolytic capacitor EC5, a resistor R88, a diode ZD21, a resistor R39, and an optocoupler TLP3. One output end of the transformer T1 is divided into two paths, one of which is connected to the E pole of the transistor Q1 and the resistor R17, and the other is grounded through the electrolytic capacitor C37. Another output end of the transformer T1 is divided into two paths, one of which is grounded through the electrolytic capacitor EC5, and the other is connected to the input end of the optocoupler TLP3 through the resistor R39 and the anode of the diode D1 through the resistor R88. The cathode of the diode D1 is connected to the output end of the transformer T1, and the input end of the optocoupler TLP3 is connected to the anode of the diode D1 through the diode ZD21. The output end of the rectifier bridge D0 is connected to the output end of the optocoupler TLP3 through the electrolytic capacitor C51 and the electrolytic capacitor EC4 in turn, and the output end of the optocoupler TLP3 is connected to the input end (pin 7) of the control chip U1. The voltage output circuit can provide a stable voltage of 220V to the flame control circuit A.

[0031] It also includes a proportional valve control circuit, a signal control circuit, an NTC acquisition circuit, a switching power supply circuit, a fan drive circuit, a fan relay, a water pump relay, a solenoid valve relay and a three-way valve relay. The control module U2 is respectively connected to the proportional valve control circuit, the signal control circuit, the NTC acquisition circuit, the switching power supply circuit, the fan drive circuit, the fan relay, the water pump relay, the solenoid valve relay and the three-way valve relay.

[0032] The control module U2 is a single chip microcomputer or other controller; the pin 40 of the control module U2 is connected to the power supply 5V, and the pin 39 of the control module U2 is grounded.

[0033] A control method for a wall-mounted boiler control circuit board comprises the following steps:

[0034] A. The control module U2 outputs a 15HZ square wave which is input to the B pole of transistor Q1 through resistor R15. Transistor Q1 amplifies the square wave signal in reverse. Then the C pole of transistor Q1 outputs the square wave signal and inputs it to the B pole of transistor Q2 through resistor R90.

[0035] B. Transistor Q2 continues to amplify the square wave signal, and then the C pole of transistor Q2 outputs the square wave signal and inputs it to coupling capacitor C104 through resistor R283. Coupling capacitor C104 inputs the square wave signal to flame detection pin X1 through resistor R288, and then flame detection pin X1 detects the flame state;

[0036] C. After the flame detection needle X1 detects the flame state, it outputs the flame signal in three ways. One way is processed by diodes D13 and D14 and then input into the control module U2. One way is sampled by resistors R280 and R281 and then input into the control module U2. One way is fed back to the control module U2 through resistors R284, R282 and R18.

[0037] D. After receiving the feedback signal, the control module U2 automatically adjusts the fan speed and the opening and closing size of the proportional valve to control the flame combustion.

[0038] The above is a preferred embodiment of the present invention, which shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for illustrating the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A wall-mounted boiler control circuit board, including a control module U2, characterized in that: It also includes a flame detection needle X1, a flame control circuit (A) and a voltage control circuit (B), wherein the flame control circuit (A) includes an amplifier circuit, a step-down circuit, a signal sampling circuit and a signal real-time feedback circuit, the control end of the control module U2 is connected to the input end of the amplifier circuit, the output end of the amplifier circuit is connected to the input end of the step-down circuit, the output end of the step-down circuit is connected to the flame detection needle X1, the flame detection needle X1 is connected to the signal sampling end of the control module U2 through the signal sampling circuit, the flame detection needle X1 is connected to the signal input end of the control module U2 through the signal real-time feedback circuit, the voltage control circuit (B) includes a rectifier circuit, a switch control circuit, an electric energy conversion circuit and a voltage output circuit, the input end of the rectifier circuit is connected to the city electricity, the output end of the rectifier circuit is connected to the electric energy conversion circuit, the control end of the switch control circuit is connected to the input end of the electric energy conversion circuit, the output end of the electric energy conversion circuit is connected to the input end of the voltage output circuit, and the output end of the voltage output circuit is connected to the voltage input end of the amplifier circuit.

2. The wall-mounted boiler control circuit board according to claim 1, characterized in that: The amplifying circuit includes a resistor R15, a transistor Q1, a resistor R90, a resistor R17, a transistor Q2 and a resistor R63. One end of the resistor R15 is connected to the control end of the control module U2, and the other end is connected to the B pole of the transistor Q1. The C pole of the transistor Q1 is connected to the B pole of the transistor Q2 through the resistor R90, and the C pole of the transistor Q2 is grounded through the resistor R63.

3. The wall-mounted boiler control circuit board according to claim 2 is characterized in that: The step-down circuit includes a resistor R283, a coupling capacitor C104 and a resistor R288. One end of the resistor R283 is connected to the C pole of the transistor Q2, and the other end is connected to one end of the coupling capacitor C104. The other end of the coupling capacitor C104 is connected to the flame detection needle X1 through the resistor R288.

4. The wall-mounted boiler control circuit board according to claim 3 is characterized in that: The signal sampling circuit includes a resistor R280, a resistor R281, a resistor R507, a resistor R508, a capacitor C521, a diode D13 and a diode D14. The flame detection needle X1 is connected to the signal sampling end of the control module U2 through the resistor R280 and the resistor R281 in sequence. One end of the resistor R281 is grounded through the capacitor C521 and the resistor R507 connected in parallel. One end of the resistor R281 is connected to the power supply 5V through the resistor R508. One end of the capacitor C521 is connected to the cathode of the diode D14. The flame detection needle X1 is connected to the cathode of the diode D13. The anode of the diode D13 is connected to the anode of the diode D14.

5. The wall-mounted boiler control circuit board according to claim 4 is characterized in that: The signal real-time feedback circuit includes resistor R284, resistor R282, resistor R18, resistor R209, resistor R161 and capacitor C136. The flame detection needle X1 is connected to the signal input end of the control module U2 through resistor R284, resistor R282 and resistor R18 in sequence. One end of the resistor R282 is grounded through the capacitor C136 and resistor R161 connected in parallel, and one end of the resistor R282 is connected to the power supply 5V through the resistor R209.

6. The wall-mounted boiler control circuit board according to claim 5, characterized in that: The rectifier circuit includes a rectifier bridge D0 and an electrolytic capacitor C51, the electrolytic capacitor C51 is connected in parallel to the output end of the rectifier bridge D0, the power conversion circuit includes a transformer T1, the output end of the rectifier bridge D0 is connected to an input end of the transformer T1, the switch control circuit includes a control chip U1, a diode D21, a resistor R1 and a capacitor C4, the output end of the rectifier bridge D0 is connected to the input end of the control chip U1, and the output end of the control chip U1 is divided into two paths, one path is connected to one input end of the transformer T1 through the diode D21 and the resistor R1 and capacitor C4 connected in parallel, and the other path is connected to the other input end of the transformer T1.

7. The wall-mounted boiler control circuit board according to claim 6, characterized in that: The voltage output circuit includes a diode D1, an electrolytic capacitor C37, an electrolytic capacitor EC5, a resistor R88, a diode ZD21, a resistor R39, and an optocoupler TLP3. One output end of the transformer T1 is divided into two paths, one path is connected to the E pole of the transistor Q1 and the resistor R17, and the other path is grounded through the electrolytic capacitor C37. The other output end of the transformer T1 is divided into two paths, one path is grounded through the electrolytic capacitor EC5, and the other path is connected to the input end of the optocoupler TLP3 through the resistor R39 and connected to the anode of the diode D1 through the resistor R88. The cathode of the diode D1 is connected to the output end of the transformer T1, the input end of the optocoupler TLP3 is connected to the anode of the diode D1 through the diode ZD21, and the output end of the optocoupler TLP3 is connected to the input end of the control chip U1.

8. The wall-mounted boiler control circuit board according to claim 7, characterized in that: It also includes a proportional valve control circuit, a signal control circuit, an NTC acquisition circuit, a switching power supply circuit and a fan drive circuit. The control module U2 is respectively connected to the proportional valve control circuit, the signal control circuit, the NTC acquisition circuit, the switching power supply circuit and the fan drive circuit.

9. The wall-mounted boiler control circuit board according to claim 1, characterized in that: The control module U2 is a single chip microcomputer.

10. The control method of the wall-mounted boiler control circuit board according to claim 8, characterized in that: The following steps are involved: A. The control module U2 outputs a 15HZ square wave which is input to the B pole of transistor Q1 through resistor R15. Transistor Q1 amplifies the square wave signal in reverse. Then the C pole of transistor Q1 outputs the square wave signal and inputs it to the B pole of transistor Q2 through resistor R90. B. Transistor Q2 continues to amplify the square wave signal, and then the C pole of transistor Q2 outputs the square wave signal and inputs it to coupling capacitor C104 through resistor R283. Coupling capacitor C104 inputs the square wave signal to flame detection pin X1 through resistor R288, and then flame detection pin X1 detects the flame state; C. After the flame detection needle X1 detects the flame state, it outputs the flame signal in three ways. One way is processed by diodes D13 and D14 and then input into the control module U2. One way is sampled by resistors R280 and R281 and then input into the control module U2. One way is fed back to the control module U2 through resistors R284, R282 and R18. D. After receiving the feedback signal, the control module U2 automatically adjusts the fan speed and the opening and closing size of the proportional valve to control the flame combustion.

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