JP3641506B2 - Gas leak alarm - Google Patents

Description

[0001]
[Industrial application fields]
The present invention includes a gas detection unit that detects a gas, an alarm output unit that outputs an alarm when gas is detected by the gas detection unit , and a power supply display unit that constantly indicates an energized state of the gas detection unit . It relates to a gas leak alarm device.
[0002]
[Prior art]
A conventional gas leak alarm device includes a gas detection unit that detects gas, an alarm output unit that outputs an alarm when gas is detected by the gas detection unit, and an energized state of the gas detection unit that is always lit. An automatic return mechanism that includes a power supply display unit, performs alarm output by the alarm output unit only while gas is detected by the gas detection unit, and stops alarm output when no gas is detected by the gas detection unit. It was provided and configured.
The reason why such an automatic return mechanism is provided is to prevent the alarm output from being determined indefinitely until the alarm output is continued after the gas leak is resolved. This is because the continuation of is unbearable for the people nearby.
[0003]
[Problems to be solved by the invention]
However, in the above-described conventional gas leak alarm device, even if an operator arrives at the site by a report based on the alarm output, the alarm output is canceled by the automatic return mechanism described above, so that a gas leak actually occurs. Therefore, there is a possibility that the operator cannot grasp how much gas has been generated and what kind of gas has been detected, so that appropriate measures cannot be performed.
In particular, in a gas leak alarm device comprising a gas detection unit that detects a plurality of types of gas and an alarm output unit that outputs a different alarm for each type of gas detected by the gas detection unit, of the gas is detected, it is very important in order to perform a subsequent appropriate action.
Therefore, it is conceivable to display or record alarm history information such as gas leak occurrence facts, gas type or gas concentration separately from the alarm output unit, but such display makes the user feel uneasy. It is not preferable to cause it to occur, and it is uneconomical to separately provide such a display or recording element.
An object of the present invention is to provide a gas leak alarm device provided with alarm history information grasping means that is excellent in economic efficiency without causing anxiety to the user in view of the above-described conventional drawbacks.
[0004]
[Means for Solving the Problems]
In order to achieve this object, the first characteristic configuration of the gas leak alarm device according to the present invention includes a gas detection unit (1) for detecting gas and an alarm when gas is detected by the gas detection unit (1). An alarm output unit (2) and a power supply display unit (4) that indicates the energized state of the gas detection unit (1) by constantly lighting , wherein the gas detection unit (1) The alarm output unit (2) outputs an alarm based on gas detection, and has an automatic return function for ending the alarm output upon completion of the gas detection, and the power display unit upon completion of the gas detection. (4) A display control unit (5) for causing the gas detection unit (1) to perform a different display according to the type or concentration of the gas detected at the time of the alarm output in a form different from the constantly lighting. It is in the point provided.
Furthermore, the second characteristic configuration includes a gas detector (1) that detects a plurality of types of gas, and an alarm output unit (2) that outputs a different alarm for each type of gas detected by the gas detector (1). ) And a power supply display unit (4) that indicates the energized state of the gas detection unit (1) by constantly lighting, and alarming based on gas detection by the gas detection unit (1) The alarm output unit (2) outputs an automatic return function that terminates the alarm output when the gas detection is completed, and the power display unit (4) displays the gas when the gas detection is completed. There is a display control unit (5) for performing a different display according to the type or concentration of gas detected at the time of the alarm output by the detection unit (1) in a form different from the constantly lighting. .
Further, the third characteristic configuration includes a gas detection unit (1) that detects gas, an alarm output unit (2) that outputs an alarm based on gas detection by the gas detection unit (1), and the gas detection unit. A gas leakage alarm device comprising a power supply display unit (4) indicating an energization state to (1), wherein the alarm output unit (2) outputs an alarm upon gas detection by the gas detection unit (1). Along with the end of the gas detection by the gas detection unit (1), the alarm output unit (2) terminates the alarm output by an automatic return function, and the power display unit (4) is in a display state. As described above, it is configured to be switchable between a constantly lit state and a gas detection information display state in which gas detection information detected at the time of gas detection by the gas detection unit (1) is displayed in a form different from the constantly lit state. With the end of the gas detection Wherein certain display state from the Steady state that comprises the gas detection information display control unit for switching the display state (5).
In the third characteristic configuration described above, the gas detection information is preferably a gas type or a gas concentration.
[0005]
[Action]
An alarm is output at the alarm output unit based on the gas detection by the gas detection unit, and an automatic return function is provided to end the alarm output upon completion of the gas detection , and the display control unit is provided with the end of the gas detection. , the power display section shown by Steady the turn-on states of the gas detection section, a different display in accordance with the type of gas or gas concentration during detected alarms by the gas detector, at different said always on, e.g. Then, signals with different duty ratios or signals with different emission luminances are added and displayed.
[0006]
【The invention's effect】
According to the present invention, with the end of gas detection, the power supply display unit that always indicates the energization state of the gas detection unit is changed according to the gas type or gas concentration at the time of alarm detected by the gas detection unit. Since the display is performed in a form different from the constant lighting , the worker can accurately grasp the gas detection information at the time of warning without notice of general users, so that the user does not feel uneasy, Moreover, it is possible to provide a gas leak alarm device equipped with an economical alarm history information grasping means.
[0007]
【Example】
Examples will be described below.
As shown in FIG. 2, the gas leak alarm device is described as a first gas sensor 1 a that detects a hydrocarbon gas such as city gas or propane gas and a carbon monoxide gas (hereinafter, “CO gas”). ) To detect a gas when a gas is detected by the gas sensors 1a and 1b, a red LED 2b mainly for a gas leak warning of combustible gas, and CO gas gas generation A yellow LED 2c mainly for warning, a green LED 4a for monitoring the energization state of the gas leak alarm, and a control circuit for controlling the operation of each of the above-described sensors and display elements are provided.
[0008]
The gas leak alarm device described above is divided into functional blocks. As shown in FIG. 1, a gas detection unit 1 that detects gas and an alarm output that outputs an alarm when gas is detected by the gas detection unit 1 2, a power supply unit 3 that supplies power to the gas detection unit 1 and the alarm output unit 2, and a power supply display unit 4 that indicates the energized state of the gas detection unit 1 or the alarm output unit 2 by constantly lighting. It consists of.
[0009]
For the first gas sensor 1a and the second gas sensor 1b, a semiconductor type gas sensor for measuring a change in electrical conductivity due to gas adsorption on the surface of the metal oxide semiconductor is used, and the gas detection unit 1 includes city gas, propane gas, etc. The first gas detection circuit 1c, the first gas temperature compensation circuit 1d, the first gas comparison circuit 1e for detecting the hydrocarbon gas, the second gas detection circuit 1f for detecting the CO gas, and the second gas temperature It comprises a compensation circuit 1g, a second gas comparison circuit 1h, and a heater control circuit 1i of the second gas sensor 1b.
The first gas detection circuit 1c includes an AC heater voltage and sensor voltage application circuit to the first gas sensor 1a, and an output circuit that converts the sensor output to DC, and the first gas temperature compensation circuit 1d. Is composed of a thermistor circuit that corrects the temperature dependence of the first gas sensor 1a, and the first gas comparison circuit 1e is composed of a comparison circuit that compares the sensor output with a two-stage reference voltage.
The second gas detection circuit 1f includes an AC high / low level heater voltage and a sensor voltage application circuit to the second gas sensor 1b, and the second gas temperature compensation circuit 1g includes the second gas sensor 1b. The second gas comparison circuit 1h is composed of a comparison circuit that compares the sensor output with a reference voltage, and the heater control circuit 1i of the second gas sensor 1b is composed of the thermistor circuit that corrects the temperature dependence of the second gas sensor 1b. As a heater voltage to the second gas sensor 1b, a transformer circuit that generates an AC heater voltage of two levels of a refresh level and a detection level is used.
[0010]
The power supply display unit 4 includes a green LED 4a indicating that a voltage is applied to a gas leak alarm and is in a gas detection state, and is also used for a warning display when a gas leak described later occurs.
[0011]
The alarm output unit 2 includes the alarm speaker 2a, the red LED 2b, the yellow LED 2c, and the control circuit 2d using a microcomputer.
The control circuit 2d alternately turns on the green LED 4a and the yellow LED 2c when the first gas sensor 1a issues a low-concentration gas leak alarm, and turns on the red LED 2b when the second-stage high concentration gas leak alarm occurs. In addition, the warning speaker 2a urges the user to be alerted by “whether gas is leaking”, while turning on the yellow LED 2c at the time of the CO gas alarm by the second gas sensor 1b, and the alarm speaker 2a. "Deep and dangerous because the air is dirty. Please ventilate." It is an automatic warning function that controls the output while gas is detected and releases the alarm when no gas is detected. Is provided.
[0012]
The power supply unit 3 includes a transformer circuit 3b that steps down from a commercial power supply via a surge protection circuit 3a, a rectifier circuit 3c that performs full-wave rectification, and a constant voltage power supply circuit 3d for DC5V control power, The output of the constant voltage power supply circuit 3d is supplied to the gas detection unit 1, the alarm output unit 2, and the power supply display unit 4.
[0013]
Even if the worker arrives after the above-described automatic return function has been activated, the gas is detected in the green LED 4a that is always lit in a normal state so that the type of detected gas can be specified and a sufficient check can be performed After the automatic return function is activated, a display control unit 5 for adding and displaying the gas detection information at the time of alarm is provided.
That is, the display control unit 5 is constituted by a part of the control circuit 2d, and when a gas leak at the time of alarm is detected by the first gas sensor 1a, as shown in FIG. Set the green LED 4a to 30 sec. Turn on, 40 msec. When the gas detection at the time of alarm is detected by the second gas sensor 1b, the green LED 4a is turned on for 30 sec. Turn on, 40 msec. Turn off the light, and further 1 sec. After lighting, 40 msec. It blinks at a cycle of turning it off.
Furthermore, the gas concentration at the time of alarm can be known by shortening the extinction cycle according to the gas concentration level. That is, when the detected gas concentration is low, it blinks at the above-mentioned 30 sec cycle, and when the detected gas concentration is high, as shown in FIG. Can do. The gas detection information displayed by the display control unit 5 is configured to be canceled when the gas leak alarm is turned off.
[0014]
Another embodiment will be described below.
In the previous embodiment, the gas detection unit 1 has been described using the first gas sensor 1a that detects hydrocarbon gas such as city gas and propane gas and the second gas sensor 1b that detects CO gas. The type of detection target gas and the number of sensors are not particularly limited. In addition to city gas, propane gas, and carbon monoxide gas, gas sensors that detect alcohol, hydrogen gas, ammonia gas, and the like are appropriately combined. The sensor used is not limited to a semiconductor type gas sensor, and the change in electric conductivity and the change in electric conductivity due to gas adsorption on the metal oxide semiconductor surface are seen from both ends of the platinum wire coil. It can be configured using any gas sensor such as a hot-wire semiconductor gas sensor or catalytic combustion gas sensor that measures resistance value changes.
Conversely, the sensitivity range of the detection target gas may be switched by switching the heater voltage, and a different type of gas may be detected using a single semiconductor gas sensor. For example, two types of gas can be detected by a single semiconductor gas sensor by heating the sensitive part to 350 ° C. when detecting city gas and lowering it to 150 to 200 ° C. when detecting CO gas.
Furthermore, for a gas leak alarm configured by providing a single gas sensor for detecting one type of gas leak, the fact that a gas leak has occurred can be confirmed by providing the display control unit 5.
The display of the green LED 4a by the display control unit 5 can be switched with an arbitrary duty ratio, but it is preferable that the duty ratio is low so that the user cannot recognize it as much as possible. Further, the light emission luminance may be switched in addition to the duty ratio, or a combination of the duty ratio and the light emission luminance may be combined. In this case, the leakage gas concentration can be easily displayed in addition to the gas type.
In addition to the green LED 4a, another display element such as a tungsten lamp may be used as the power display unit 4.
Furthermore, when LP gas and CO gas generated by its incomplete combustion are detected as gas leaks of two types of gases with different specific gravity, for example, fuel gas, LP gas has a large specific gravity and stays on the floor surface. The gas sensor 1a for detecting the gas is separated from the gas leak alarm 10 and installed near the floor, or the gas leak alarm 10 is installed near the floor and the gas sensor 1b is separated and installed near the ceiling. Is reasonable.
[0015]
In addition, although the code | symbol is described in the item of a claim for convenient comparison with drawing, this invention is not limited to the structure of an accompanying drawing by this entry.
[Brief description of the drawings]
[Fig. 1] Functional block diagram of a gas leak alarm [Fig. 2] Perspective cutaway view of a gas leak alarm [Fig. 3] Time chart [Fig. 4] Time chart [Explanation of symbols]
1 Gas detection unit 2 Alarm output unit 4 Power supply display unit 5 Display control unit

Claims (4)

A gas detection unit (1) for detecting gas, an alarm output unit (2) for outputting an alarm when gas is detected by the gas detection unit (1), and an energization state to the gas detection unit (1) A gas leak alarm comprising a power display (4) that is always lit ,
Based on gas detection by the gas detection unit (1), an alarm is output in the alarm output unit (2), and an automatic return function is provided to end alarm output when the gas detection ends,
Along with the end of the gas detection, a different display according to the type or concentration of gas detected at the time of the alarm output by the gas detection unit (1) on the power supply display unit (4) Is a gas leak alarm provided with a display control unit (5) to be performed in different forms . A gas detection unit (1) for detecting a plurality of types of gas, an alarm output unit (2) for outputting a different alarm for each type of gas detected by the gas detection unit (1), and the gas detection unit (1 ) Is a gas leakage alarm device comprising a power supply indicator (4) that constantly indicates the energization state,
Based on gas detection by the gas detection unit (1), an alarm is output in the alarm output unit (2), and an automatic return function is provided to end alarm output when the gas detection ends,
Along with the end of the gas detection, a different display according to the type or concentration of gas detected at the time of the alarm output by the gas detection unit (1) on the power supply display unit (4) Is a gas leak alarm provided with a display control unit (5) to be performed in different forms . The gas detection part (1) which detects gas, the alarm output part (2) which outputs an alarm based on the gas detection by the said gas detection part (1), and the energization state to the said gas detection part (1) are shown A gas leak alarm device comprising a power display (4),
When the gas is detected by the gas detector (1), the alarm output unit (2) outputs an alarm, and when the gas detection by the gas detector (1) ends, the alarm is output by an automatic return function. Part (2) ends the alarm output,
Gas detection information display in which the power supply display unit (4) displays as a display state a constantly lit state and gas detection information detected at the time of gas detection by the gas detection unit (1) in a form different from the constantly lit state. Configured to be switchable between states,
A gas leakage alarm device comprising a display control unit (5) that switches the display state from the constantly lit state to the gas detection information display state as the gas detection ends. The gas leak alarm according to claim 3, wherein the gas detection information is a gas type or a gas concentration.

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