KR19980060874U - Gas Detector for Combustor - Google Patents

Abstract

The present invention relates to a gas detector for a combustion device, in the combustion device, a first detection unit 20 for detecting flammable gas, a second detection unit 40 for detecting carbon monoxide, and an alternating current or direct current input from outside The constant voltage switching unit 10 converts the power into a constant voltage and outputs the voltage in a constant voltage state, and detects the temperature change to compensate for the sensitivity change of the combustible gas and carbon monoxide according to the temperature inside the combustion device 80. The temperature sensing unit 30 configured with the MR TH and the sensing concentration of the combustible gas and the carbon monoxide are set and input from the first sensing unit 20, the second sensing unit 40, and the temperature sensing unit 30. And a control unit 60 for outputting a control signal by comparing the calculated signals, an alarm unit 50 for generating an audiovisual alarm display and an alarm sound with the control signal input from the control unit 60, and the control unit 60. Output from It is included as an output unit 70 that amplifies the control signal to a predetermined size and outputs it to the combustion device 80 or the controller, and detects carbon monoxide generated by leakage of inflammable gas or incomplete combustion in the combustion device. To generate.

Description

Gas Detector for Combustor

The present invention relates to a gas detector of a combustion device, and more particularly, to a gas detector for a combustion device for generating an electrical signal by detecting a carbon monoxide generated due to leakage or incomplete combustion of flammable gas in the combustion device.

The combustion device burns fuel having excellent thermal efficiency such as LPG gas, LNG gas or petroleum, and heats a predetermined space or supplies hot water by using heat generated during combustion. The type of boiler differs depending on the fuel used, such as gas boiler, oil boiler, briquette boiler, wood boiler, etc., but most of the unburned gas or incomplete gas generated by the burning fuel is toxic. These toxic gases are not only harmful to the human body, but there is a risk of explosion due to user's carelessness when unburned gas is generated.

Such a conventional combustor has a state in which a sensor for detecting a toxic gas generated due to unburned or unburned fuel in a combustor is disclosed, as disclosed in Japanese Patent Publication JP90-38857 of FIG. 1. In the cross-sectional view, a gas sensor 3 is mounted on one end of the burner 2 for burning fuel in the combustion device 1, and the gas sensor 3 is connected to a separate warning means, not shown. The gas sensor 3 may be a gas generated by ignition failure or unignition generated when the burner 2 in the combustion device 1 is ignited, or gas by incomplete combustion generated immediately after the burner 2 is ignited. And a safety combustion device configured to detect an unburned or incombustible state of the combustion apparatus 1 through warning means and the like by converting the signal into an electrical signal.

In this case, however, the safety combustion device detects and alarms only an incomplete combustion state due to its own defects, that is, poor ignition or non-ignition in the burner or momentary excessive combustion immediately after ignition. Gas leaked from a specific part due to defect or failure or gas leaked due to pipe problem connected from fuel tank cannot be easily detected by the gas sensor. If the waste gas enters the room without permission, it could not be detected properly.

In addition, by detecting a gas such as carbon monoxide formed by leaking around the combustion equipment, using a gas leakage alarm, or using a carbon monoxide alarm that detects carbon monoxide in accordance with the use of a fireplace or stove in the room. have. However, all of these constitute a circuit that detects gas by receiving a separate power source from the outside, and emits only an alarm sound through the alarm means when gas is detected. In the case of the gas leakage alarm, it is possible to send an electric signal sensed when the gas leaks to the outside, but even in this case there is a problem that does not detect the carbon monoxide and can not detect the gas formed by leakage from the inside of the combustion device .

The present invention has been made to solve the above problems, and the use of carbon monoxide or waste gas generated by the gas leakage generated in the combustion apparatus inside or surrounding piping when the use of the combustion equipment or the lack of air in the continuous use in a narrow space Provides a gas detector of a combustion device to detect an inflow and send an electrical signal to the combustion device after a predetermined time has elapsed to stop the operation of the combustion device or generate an alarm sound to prevent human and property damage. The purpose is to.

1 is a cross-sectional view showing a state in which a sensor for detecting a gas generated due to unburned or non-burned in a conventional combustion device,

2 is a circuit diagram illustrating a gas detector for a combustion device according to the present invention;

3 is a cross-sectional view showing a state in which a gas detector is mounted in a combustion device according to the present invention;

Figure 4 is a front view showing an open state of the cover of the gas detector applied in the present invention.

♣ Explanation of symbols for the main parts of the drawing ♣

10: constant voltage switching unit 20: first detection unit

30: temperature detection unit 40: second detection unit

50: alarm means 60: control unit

70: output unit 80: combustion device

82: burner 90: gas detector

91a, 91b: fixed part 92: printed circuit board

94: cable 96: grille

98: case T1: transformer

D1-D4: Diode LED1, LED2: Light Emitting Diode

ZD1, ZD2: Zener Diode U1: Microprocessor

U2, U4: OP amplifier U3: integrated circuit

R1-R33: resistors S1, S2: gas sensor

TH: Thermistor C1-C6: Condenser

TR1-TR7: Transistors J1, J2: Jumpers

L1: Inductor

In order to achieve the above object, the present invention provides a combustor comprising: a first sensing unit for detecting combustible gas, a second sensing unit for sensing carbon monoxide, and an alternating current or direct current power source input from an external device And a temperature sensing unit configured to detect the temperature change to compensate for the sensitivity change of the combustible gas and the carbon monoxide according to the temperature inside the combustion apparatus, and the combustible gas and the carbon monoxide. A control unit configured to output a control signal by comparing a signal input from the first sensing unit, the second sensing unit, and the temperature sensing unit with a sensing concentration of the control unit, an audiovisual alarm display using the control signal input from the control unit, and Alarm means for generating an alarm sound, and the combustion signal by amplifying the control signal output from the control unit to a predetermined magnitude It is characterized by including an output unit for outputting to the controller or controller.

Hereinafter, a gas detector for a combustion device of the present invention will be described with reference to the accompanying drawings.

2 is a circuit diagram illustrating a gas detector for a combustion device according to the present invention.

The transformer T1 converts the AC power AC input from the outside into a constant voltage and outputs the voltage. The transformer ratio varies according to the winding ratios of the primary side and the secondary side.

The constant voltage switching unit 10 converts the AC power source AC or the DC power source VH input from the transformer T1 into a voltage of a constant size and outputs the voltage in a constant voltage state so that the transformer is not excessively loaded. The current supplied to the entire circuit of the gas detector is rectified and transformed to be adjusted. Alternatively, the Zener diode ZD1, the inductor L1, the OP amplifier U2, the first and second transistors TR1 and TR2, the plurality of resistors R3 and R4, and the capacitor may be loaded as little as possible to the other input power source. (C4) or the like is used to convert a voltage of a certain magnitude (for example, 5 V is used as the driving voltage).

The first detecting unit 20 detects flammable gas generated inside or outside the combustion apparatus, and the first detecting unit 20 includes a semiconductor gas sensor S1 having tin oxide SnO 2 as a main raw material. . The gas sensor S1 compares the first heater coil RH1 for heating to a constant temperature, the load resistor R9 having a predetermined magnitude of resistance, and the load resistance R9 and the resistance value according to the detected gas concentration. The first sensor resistor RS1 is configured in series and parallel.

The temperature detector 30 detects a temperature change in the gas detector and outputs a detected signal to compensate for the sensitivity change of the combustible gas and carbon monoxide according to the temperature. Thermistor TH1 and the plurality of resistors R8, R10, R11) is connected in series.

The second detecting unit 40 detects carbon monoxide (CO) formed inside and outside the combustion apparatus, and in order to detect carbon monoxide, the tin raw material Sn02 is used as the main raw material as the sensor S1 detecting the combustible gas. In order to detect only carbon monoxide in the semiconductor type gas sensor S2, the high current and the low current flow alternately for a predetermined time. The second sensing unit 40 includes the second and third heater coils RH2 and RH3 composed of both electrodes of the gas sensor S2, and the second sensor resistor RS2 is configured in series thereto, and the load resistor It is connected in series with (R33) and the same circuit configuration as the gas sensor (S1) for detecting the combustible gas is made, the detection action is the same. In addition, the second sensing unit 40 includes fifth to seventh transistors TR5-TR7 connected in series and in parallel with the gas sensor S2.

The control unit 60 detects the concentration of the flammable gas and the carbon monoxide, and compares the signals input from the first and second sensing units 20 and 40 and the temperature sensing unit 30 to control signals. The output includes a microprocessor U1, an integrated circuit U3, and peripheral elements thereof.

The alarm means 50 generates an audiovisual alarm indication and an alarm sound by the control signal input from the output terminal of the controller 60. The light emitting diodes LED2 and the buzzer 52 are configured in parallel.

The output unit 70 amplifies the control signal output from the control unit 60 to a predetermined size and outputs it to a combustion device or a controller, and outputs a control signal or data signal output from the microprocessor U1 to an OP amplifier U4. ) And the third transistor TR3 are sufficiently amplified to a certain size and output through the output terminal.

3 is a cross-sectional view showing a state in which a gas detector is mounted in the combustion apparatus according to the present invention, Figure 4 is a front view showing an open state of the cover of the gas sensor applied in the present invention, the interior of the combustion device 80 and The case 98 has a structure in which one surface is opened to simultaneously detect external gas leakage, and a grill 96 having a predetermined size and a plurality of perforations is formed on the outer circumferential surface to detect flammable gas, incomplete combustion gas or waste gas. And an electrical signal detected and converted after a predetermined time has elapsed by being connected to a printed circuit board 92 having various components mounted in the case 98 and an input / output terminal of the printed circuit board 92. The cable 94 for outputting to the combustion device is separated from the power input line. In the structure of the case 98 of the gas detector 90, one side of the case 98 is opened, and the other side is inserted with a grill 96 to perforate the open surface or treated with the grill 96 ( Attached to one side of the 80 to detect both the combustible gas and carbon monoxide formed in the interior and exterior of the combustion device (80). The gas detector 90 has fixing parts 91a and 91b respectively formed at upper and lower ends thereof so as to be mounted on one side of the combustion device 80.

Referring to the operation of the gas detector of the combustion device of the present invention configured as described above in detail as follows.

The gas sensor S1 of the first sensing unit 20 is an n-type semiconductor. When oxygen in the atmosphere is adsorbed on the surface of the gas sensor S1, free electrons in the semiconductor are trapped by the adsorbed oxygen, and the resistance thereof is reduced. In this case, when the combustible gas or the reducing gas is present, the oxygen adsorbed on the surface of the gas sensor S1 is removed, and the trapped electrons are returned to the sensor to reduce its resistance again.

Combustible gases such as LPG (liquefied petroleum gas) and LNG (liquefied natural gas) react well at around 300-400 ° C. When the driving voltage VC is applied to the first heater coil RH1 of the gas sensor S1, the surface temperature of the gas sensor S1 is about 300-400 ° C., thereby easily detecting flammable gas. In order to change the resistance change of the gas sensor S1 into a change in voltage, when the driving voltage VC is applied by connecting the gas sensor S1 and the load resistor R9 in series, 5 × R9 / The voltage of (R9 + RS1) is applied. In the clean air, the first sensor resistance RS1 of the gas sensor S1 is considerably larger than the load resistance R9, and a low voltage of less than a constant voltage (1V) is applied. RS1) is unexpectedly lowered and a high voltage is applied to the load resistor R9. That is, when the combustible gas is detected at a certain amount (thousands of ppm), the voltage applied to the load resistor R9 is input to the microprocessor U1 of the controller 60.

When the concentration of the combustible gas formed around the combustion device 80 reaches a predetermined value, an electrical signal is sent after a delay of a predetermined time (several seconds).

Unlike the gas sensor S1 of the first sensing unit 20 that detects the combustible gas, a different method is used to detect carbon monoxide. That is, carbon monoxide reacts well at low temperatures below 100 ° C. unlike flammable gases. Therefore, the gas sensor S2 of the second sensing unit 40 is heated to a high temperature for a predetermined time (about 1 minute) to remove miscellaneous gas for a predetermined time (minutes), and then immediately for a predetermined time (about 1 minute and 30 seconds). When cooled to low temperature, it reacts easily with air carbon monoxide. Periodically applying this action will detect carbon monoxide.

As described above, the second sensing unit 40 turns on the fifth transistor TR5 and the sixth transistor TR6 to maintain the gas sensor S2 at a high temperature, and applies the driving power VC. The resistance (R28) is adjusted so that a constant current (about 370 mA) flows. In addition, in order to maintain the low temperature, the sixth transistor TR6 is turned off, the fifth resistor TR5 and the seventh transistor TR7 are turned on, and a load current flows for a predetermined current (about 130 mA) to flow. Adjust the resistance value of (R32). As such, when all of the fifth to seventh transistors TR5-TR7 are turned off immediately before the transition from the low-temperature period to the high-temperature period, the second and third heater coils RH2 and RH3 turn off the gas sensor S2. It acts as both electrodes of, and is connected in series with the second sensor resistor (RS2) and the load resistor (R33) in the same circuit as the gas sensor (S2) to facilitate the detection of carbon monoxide.

The first detector 20 continuously detects the combustible gas, but the second detector 40 detects the carbon monoxide at a predetermined time interval (about 2 minutes and 30 seconds) to detect the detected value. Continue to hold until the next detection in U1). The combustible gas or carbon monoxide detected by the microprocessor U1 is amplified to a predetermined size by the OP amplifier U4 of the output unit 70 and output to the output terminal through the third transistor TR3. At this time, the signal output to the output terminal is received by the controller of the combustion device 80 (not shown) to stop the operation of the combustion device or to take a separate action. In addition, when the sensed value is larger than the set value, the microprocessor U1 drives the light emitting diode LED2 and the buzzer 52 of the alarm means 50 connected to the output terminal to inform the user of the combustion apparatus situation. In order to detect the flammable gas or carbon monoxide or to notify the failure state of the gas sensor (S1, S2), the light emitting diode (LED1) is divided into the blinking interval and the lighting. That is, when detecting flammable gas, for example, 0.8 second interval, 1.6 seconds interval when detecting carbon monoxide, 0.4 seconds interval when both flammable gas and carbon monoxide are detected, and blinks when gas sensor (S1, S2) malfunctions. Can be displayed as a state.

As described above, the gas detector for the combustion device of the present invention uses a power source of the combustion device or a separate external power source to detect the combustible gas and carbon monoxide inside or outside the combustion device, respectively, so that the gas sensor is electrically connected to the combustion device. By sending a signal, the combustion apparatus automatically stops driving or displays an alarm, thereby preventing the damage to human life and property due to flammable gas or carbon monoxide.

Claims (2)

A combustion device comprising: a first sensing unit for detecting combustible gas, a second sensing unit for sensing carbon monoxide, and a constant voltage switching unit for converting AC or DC power input from the outside into a constant voltage and outputting a constant voltage state And a temperature detector configured to detect a temperature change to compensate for the sensitivity change of the combustible gas and the carbon monoxide according to the temperature inside the combustion device, and a detection concentration for the combustible gas and the carbon monoxide. A control unit for comparing and calculating a signal input from the second and second sensing units and the temperature sensing unit and outputting a control signal, an alarm means for generating an audiovisual alarm display and an alarm sound with the control signal input from the control unit, and the control unit Amplifying the control signal output from the output to a predetermined size and includes an output unit for output to the combustion device or controller Gas detector for the combustion device, characterized in that made. The method of claim 1, wherein one surface of the combustion apparatus has an open structure for simultaneously detecting internal and external gas leakage, and has a predetermined size and plurality in order to detect flammable gas, incomplete combustion gas, or waste gas on the outer circumferential surface. A power supply inputs a case having a perforated grill, a printed circuit board having various components mounted therein, and an electrical signal detected and converted after a predetermined time has elapsed connected to an input / output terminal of the printed circuit board. A gas detector for a combustion device, characterized in that it further comprises a cable separated from the line to output to the combustion device.