JP2005004267A - Gas leak alarm and lighting control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas leak alarm which does not glare in monitoring and illuminates brightly in generating an alarm. <P>SOLUTION: A CPU 20a controls a SW transistor Tr<SB>0</SB>so as to turn off when a gas sensor 30 detects no gas leak. Consequently, an LED 10 illuminates with low luminance. When the gas sensor 30 detects a gas leak, the SW transistor Tr<SB>0</SB>is repeatedly turned on and off. Thus, the LED 10 repeatedly illuminates with high luminance and low luminance alternately, in other words blinks at high luminance. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas leak alarm and a lighting control method, and more particularly to a gas leak alarm provided with a light emitting element and a lighting control method for a light emitting element provided in the gas leak alarm.
[0002]
[Prior art]
As a conventional gas leakage alarm device, for example, a device including a power display light emitting diode (hereinafter referred to as an LED) that is always lit during power-on and an alarm LED that is lit when a gas leakage alarm is known. By turning on / off the power display LED and the alarm LED, the user can know information such as whether power is supplied to the gas leak alarm and whether gas leak has occurred.
[0003]
[Problems to be solved by the invention]
In the conventional gas leak alarm described above, the power supply LED and the alarm LED are lit with the same luminance. For this reason, if the emission brightness of the power indicator LED and the alarm LED is increased so that the location of the gas leak alarm can be found immediately at the time of alarm, the gas leak will occur in dark places such as at night during monitoring other than during alarm. Since the power display LED of the alarm device is lit with high brightness, there is a problem that the alarm device is excessively dazzled.
[0004]
In addition, if the emission brightness of the power display LED and the alarm LED is lowered so that the gas leak alarm device is not dazzled when monitoring, the alarm LED will turn on at a low brightness at the time of alarm, so it will stand out. This causes a problem that it is difficult to quickly find the location of the gas leak alarm at the time of alarm.
[0005]
Therefore, the present invention pays attention to the above-described problems, and an object thereof is to provide a gas leak alarm device that emits bright light at the time of alarm without being dazzled at the time of monitoring.
[0006]
[Means for Solving the Problems]
The invention according to claim 1, which has been made to solve the above problem, is a gas leak alarm device comprising a detection means for detecting a gas leak and a light emitting element, and at least when the gas leak is not detected. The gas leakage alarm device includes lighting control means for lighting the light emitting element with low luminance and lighting the light emitting element with high luminance when the gas leakage is detected.
[0007]
According to the first aspect of the present invention, the lighting control means turns on the light emitting element at a low luminance at least when no gas leakage is detected, and turns on the light emitting element at a high luminance when gas leakage is detected. Light up. Accordingly, the light emitting element can be turned on at a low luminance during monitoring when no gas leak is detected, and the light emitting element can be turned on at a high luminance during an alarm when gas leakage is detected.
[0008]
Invention of Claim 2 is the gas leak alarm device of Claim 1, Comprising: The said lighting control means always makes the said light emitting element light, and when the said gas leak is detected, the said gas leak is The gas leak alarm device is characterized in that the luminance of the light emitting element is increased as compared with the case where the light is not detected.
[0009]
According to the second aspect of the present invention, the lighting control means always turns on the light emitting element, and when the gas leak is detected, the brightness of the light emitting element is higher than when the gas leak is not detected. To do. Therefore, the luminance at the time of monitoring and at the time of alarm can be changed with one light emitting element.
[0010]
The invention according to claim 3 is the gas leak alarm according to claim 2, wherein the light emission control means includes a parallel circuit in which a resistor and a switching element are connected in parallel to each other, and a switch for controlling on / off of the switching element. And the parallel circuit is connected in series with the light emitting element, and the switch control means turns off the switching element and detects the gas leak when the gas leak is not detected. In the gas leak alarm device, the switching element is repeatedly turned on and off.
[0011]
According to the third aspect of the invention, the switch control means turns off the switching element when no gas leak is detected, and repeats the on / off operation of the switching element when the gas leak is detected. Therefore, by simply performing on / off control of one switching element, when a gas leak is not detected, the light emitting element is turned on with low brightness, and when a gas leak is detected, the light emitting element is turned on with high brightness. Can be flashed.
[0012]
The invention according to claim 4 is the gas leak alarm device according to claim 2, wherein the light emission control means includes a series circuit in which a resistor and a first switching element are connected in series, and a second switching element. A parallel circuit in which the series circuit and the second switching element are connected in parallel to each other, and a switch control means for controlling on / off of the first and second switching elements, the switch control element having the gas leakage When not detected, the first switching element is turned on and the second switching element is turned off, and when the gas leakage is detected, the first switching element is turned off and the second switching element is turned off. The gas leak alarm device is characterized by repeating the on / off operation of the element.
[0013]
According to the fourth aspect of the present invention, when the gas leakage is not detected, the switch control means turns on the first switching element and controls the second switching element to be off. On the other hand, when the gas leakage is detected, the first switching element is turned off, and the on / off operation of the second switching element is repeated. Therefore, by performing on / off control of the first and second switching elements, the light emitting element is turned on with low brightness when no gas leak is detected, and the light emitting element with high brightness when gas leak is detected. Can be flashed. In addition, since the first switching element is turned off at the time of blinking, the light emitting element is turned on with high luminance when the second switching element is turned on, and when the second switching element is turned off, the light emitting element does not emit light completely. The brightness of flashing can be increased.
[0014]
The invention according to claim 5 is a lighting control method of a light emitting element provided in a gas leak alarm device, and at least when the gas leak is not detected, the light emitting element is turned on with low luminance, and the gas leak is detected. In the lighting control method, the light emitting element is turned on with high brightness when the light is detected.
[0015]
According to the fifth aspect of the invention, at least when the gas leak is not detected, the light emitting element is turned on with low brightness, and when the gas leak is detected, the light emitting element is turned on with high brightness. Accordingly, the light emitting element can be turned on at a low luminance during monitoring when no gas leak is detected, and the light emitting element can be turned on at a high luminance during an alarm when gas leakage is detected.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
First embodiment Hereinafter, a gas leak alarm and a lighting control method according to a first embodiment will be described with reference to the drawings. FIG. 1 is an electrical configuration diagram of a gas leak alarm device that performs the lighting control method according to the first embodiment. As shown in the figure, a resistor R ₀ , a light emitting diode (LED) 10 as a light emitting element, and a parallel circuit 11 are connected in series to the DC power source _VCC . The parallel circuit 11 includes a switching transistor (SW transistor) Tr ₀ and a resistor R ₁ connected in parallel to each other.
[0017]
The base of the SW transistor Tr ₀ as the switching element is connected to a microcomputer (μCOM) 20, and this μCOM 20 functions as switch control means, and outputs a control signal S 1 to the base of the SW transistor Tr _0. Control on / off.
[0018]
As described above, the μCOM 20 includes a central processing unit (CPU) 20a that performs various processes and controls according to a predetermined program, a ROM 20b that is a read-only memory storing a program for the CPU 20a, and various data. And a RAM 20c, which is a readable / writable memory having an area necessary for processing operations of the CPU 20a. The CPU 20a is supplied with a detection result from a gas sensor 30 that detects gas leakage.
[0019]
According to the gas leak alarm having the above-described configuration, when the SW transistor Tr ₀ is turned off, the LED 10 receives a current corresponding to the series combined resistance of the resistor R ₀ , the LED 10, and the resistor R ₁ from the DC power supply _VCC. Supplied. On the other hand, if turning on the SW transistor Tr _0, the LED 10, the resistor _R 0, a current corresponding to the series combined resistance of the LED 10 is supplied from the DC power supply _{V CC.} At this time, the current supplied to LED10, since the series combined resistance decreases resistance R ₁ min, increased than when turning off the SW transistor Tr _0. Accordingly, the LED 10 is lit with low luminance when the SW transistor Tr ₀ is turned off, and is lit with high luminance when the SW transistor Tr ₀ is turned on.
[0020]
Next, the operation of the gas leak alarm device configured as above will be described below with reference to the on-off timing chart of the SW transistor Tr ₀ shown in FIG.
The CPU 20a in the μCOM 20 starts operation when the power is turned on. Then, CPU 20a while the detection result of that no gas leak occurs from the gas sensor 30 has been obtained, it is determined that the time monitoring, the control signal supplied to the base of the SW transistor Tr ₀ to L _o Te, to turn off the SW transistor Tr _0. Thereby, LED10 lights with low brightness.
[0021]
On the other hand, when the gas sensor 30 detects a gas leak, CPU 20a determines that a time alarm, and outputs a control signal S1 pulsed into the base of the SW transistor Tr _0, to repeat off the SW transistor Tr ₀ . Thereby, LED10 repeats high-intensity lighting and low-intensity lighting, that is, blinks with high luminance.
[0022]
According to the above gas leak alarm device, the LED 10 is always turned on, and when the gas leak is detected, the brightness of the LED 10 is made higher than when the gas leak is not detected. As a result, the LED 10 can be lit at a low luminance during monitoring and can be lit at a high luminance during alarming. In addition, since one LED 10 is lit at a low luminance during monitoring and is lit at a high luminance at the time of alarm, it is not necessary to provide separate LEDs 10 for low luminance lighting and high luminance lighting, thereby reducing costs. Can do.
[0023]
In addition, according to the above-described gas leak alarm device, it is possible to simply turn on the LED 10 with low brightness at the time of monitoring and blink the LED 10 with high brightness at the time of alarm simply by performing on / off control of one SW transistor Tr _0. it can. For this reason, the configuration is simplified and the cost can be reduced.
[0024]
Second embodiment Next, a gas leak alarm and a lighting control method in the second embodiment will be described with reference to the drawings. FIG. 3 is an electrical configuration diagram of a gas leak alarm device that performs the lighting control method according to the second embodiment. As shown in the figure, the DC power supply _{V CC,} a resistor _{R 0,} LED 10, and the parallel circuit 11 are connected in series with each other. The parallel circuit 11 is composed of a series circuit of a SW transistor Tr ₀ connected in parallel to each other, a resistor R ₁ and a SW transistor Tr ₁ . The SW transistor Tr _{0 corresponds} to the second switching element in the claims, and the SW transistor Tr ₁ corresponds to the first switching element in the claims.
[0025]
The bases of the SW transistors Tr ₀ and Tr ₁ are each connected to the μCOM 20, and the μCOM 20 functions as a switch control unit, and outputs control signals S 1 and S 2 to the bases of the SW transistors Tr ₀ and Tr ₁ , respectively. Control on / off.
[0026]
The μCOM 20 described above includes a CPU 20a, a ROM 20b, a RAM 20c, and the like, as in the first embodiment described above. The CPU 20a is supplied with a detection result from a gas sensor 30 that detects gas leakage.
[0027]
According to the gas leak alarm having the above-described configuration, when the SW transistor Tr ₀ is turned off and the SW transistor Tr ₁ is turned on, the LED 10 has a resistance R ₀ , an LED 10, and a resistance R ₁ in accordance with the series combined resistance. Current is supplied from the DC power supply _VCC . On the other hand, turning on SW transistor Tr _0, the LED 10, the resistor _R 0, a current corresponding to the series combined resistance of the LED 10 is supplied from the DC power supply _{V CC.} At this time, the current supplied to the LED 10 is larger than when the SW transistor Tr ₀ is turned off and the SW transistor Tr ₁ is turned on because the series combined resistance decreases by the resistance R ₁ .
[0028]
For this reason, the LED 10 is turned on with low luminance when the SW transistor Tr ₀ is turned off and the SW transistor Tr ₁ is turned on, and is turned on with high luminance when the SW transistor Tr ₀ is turned on. If both the SW transistors Tr ₀ and Tr ₁ are turned off, no current is supplied to the LED 10 and the LED 10 is turned off.
[0029]
Next, the operation of the gas leak alarm having the above-described configuration will be described below with reference to an on / off timing chart of the SW transistors Tr ₀ and Tr ₁ shown in FIG.
The CPU 20a in the μCOM 20 starts operation when the power is turned on. Then, CPU 20a is, while the detection result of that no gas leak occurs from the gas sensor 30 is obtained, it is determined that the time monitoring, the control signal S1 supplied to the base of the SW transistor Tr ₀ L _o while in the SW transistor Tr control signal S2 supplied to the base of ₁ to _{H i.} Thereby, LED10 lights with low brightness.
[0030]
On the other hand, when the gas sensor 30 detects a gas leak, CPU 20a determines that a time alarm, and outputs a pulsed control signal S1 to the base of the SW transistor Tr _0, and repeats the on-off of the SW transistor Tr ₀ together, the SW transistor Tr control signal S2 supplied to the base of ₁ to _{L o.} As a result, the LED 10 repeatedly turns on and off with high brightness, that is, blinks with high brightness.
[0031]
Similarly to the first embodiment, the gas leak alarm device of the second embodiment always turns on the LED 10, and when the gas leak is detected, the brightness of the LED 10 is higher than when the gas leak is not detected. Is high. As a result, the LED 10 can be lit at a low luminance during monitoring and can be lit at a high luminance during alarming. In addition, since one LED 10 is lit at a low luminance during monitoring and is lit at a high luminance at the time of alarm, it is not necessary to provide separate LEDs 10 for low luminance lighting and high luminance lighting, thereby reducing costs. Can do.
[0032]
In addition, when the SW transistor Tr ₁ is turned off at the time of blinking, the LED 10 is turned on with high brightness when the SW transistor Tr ₁ is turned on, and when it is turned off, the LED 10 does not emit light completely. And the visibility can be improved.
[0033]
In the first and second embodiments described above, one LED 10 is always lit and its luminance is changed. However, for example, two LEDs 10 for low luminance lighting and high luminance lighting may be provided. It is done. Further, when two LEDs 10 are provided, the low-luminance LED 10 is not limited to when no gas leak occurs as in the first and second embodiments, but may be constantly lit.
[0034]
In the first and second embodiments described above, the lighting control of the LED 10 is performed using the μCOM 20. However, it is also conceivable to perform the lighting control of the LED 10 by using the control circuit shown in FIG. 5 without using the μCOM.
[0035]
In this case, when the comparator CP does not detect gas leakage and the output is at the H level, when the DC power supply Vcc is supplied, a bias voltage is supplied between the base and the emitter of the transistor Tr1, and the transistor Tr1 is turned on. Thus, the LED 10 is always lit. Further, the comparator CP is used to detect that the output of the gas sensor 30 is equal to or greater than a certain value and gas leakage has occurred.
[0036]
When the comparator CP detects a gas leak and its output changes from the H level to the L level, the oscillation circuit 40 operates, a pulsed bias voltage is supplied between the base and emitter of the transistor Tr0, and the LED 10 blinks. . At this time, since the output of the comparator CP becomes L level, no current flows through the bias resistor Rv of the transistor Tr1, and the transistor Tr1 is turned off.
[0037]
【The invention's effect】
As described above, according to the first and fifth aspects of the present invention, the light emitting element is turned on at a low luminance during monitoring when no gas leakage is detected, and the high luminance is generated at an alarm when gas leakage is detected. Since the light emitting element can be turned on, it is possible to obtain a gas leak alarm device and a lighting control method that emit light brightly at the time of alarm without being dazzled at the time of monitoring.
[0038]
According to the invention described in claim 2, since it is possible to change the luminance at the time of monitoring and at the time of alarm with one light emitting element, it is not necessary to provide a light emitting element for low luminance lighting and for high luminance lighting, It is possible to obtain a gas leak alarm device that reduces costs.
[0039]
According to the third aspect of the present invention, the gas leakage is detected simply by performing on / off control of one switching element, and when the gas leakage is not detected, the light emitting element is turned on with low brightness. Since the light-emitting element can be blinked with high brightness, the configuration is simplified, and a gas leak alarm device with reduced cost can be obtained.
[0040]
According to the invention of claim 4, by performing on / off control of the first and second switching elements, when no gas leak is detected, the light emitting element is turned on with low brightness, and the gas leak is detected. The light emitting element can be blinked with high brightness. In addition, since the first switch element is turned off at the time of flashing, the light emitting element is turned on with high luminance when the second switching element is turned on, and when the second switching element is turned off, the light emitting element does not emit light completely. Since the brightness of the flashing can be increased, the flashing of the light emitting element is emphasized, and a gas leak alarm device with improved visibility can be obtained.
[Brief description of the drawings]
FIG. 1 is an electrical configuration diagram of a gas leak alarm device that performs a lighting control method according to a first embodiment.
2 is a on-off timing chart of the SW transistor Tr ₀ shown in FIG.
FIG. 3 is an electrical configuration diagram of a gas leak alarm device that performs a lighting control method according to a second embodiment.
4 is an on / off timing chart of SW transistors Tr ₀ and Tr ₁ shown in FIG.
FIG. 5 is an electrical configuration diagram of a gas leak alarm device that performs a lighting control method according to a second embodiment.
[Explanation of symbols]
30 Gas sensor (detection means)
10 LED (light emitting element)
20a CPU (lighting control means)
Tr ₀ SW transistor (switching element, second switching element)
Tr ₁ SW transistor (first switching element)
R ₁ resistance

Claims (5)

A gas leakage alarm device comprising a detecting means for detecting gas leakage and a light emitting element,
At least when the gas leak is not detected, the light-emitting element is turned on with low brightness, and when the gas leak is detected, the lighting control means is provided for turning on the light-emitting element with high brightness. Gas leak alarm. The gas leak alarm according to claim 1, wherein
The lighting control means always turns on the light emitting element, and increases the luminance of the light emitting element when the gas leak is detected as compared to when the gas leak is not detected. Gas leak alarm. The gas leak alarm according to claim 2,
The light emission control means includes a parallel circuit in which a resistor and a switching element are connected in parallel to each other, and a switch control means for controlling on / off of the switching element,
The parallel circuit is connected in series with the light emitting element,
The switch control means turns off the switching element when the gas leak is not detected, and repeats the on / off operation of the switching element when the gas leak is detected. Alarm. The gas leak alarm according to claim 2,
The light emission control means includes a series circuit in which a resistor and a first switching element are connected in series, and a second switching element, and a parallel circuit in which the series circuit and the second switching element are connected in parallel to each other; Switch control means for controlling on / off of the first and second switching elements;
The switch control element controls the first switching element to be turned on and the second switching element to be turned off when the gas leakage is not detected, and when the gas leakage is detected, the first switching element is turned on. A gas leakage alarm device, wherein the switching element is turned off and the on / off operation of the second switching element is repeated. A lighting control method for a light emitting element provided in a gas leak alarm,
A lighting control method characterized in that at least when the gas leak is not detected, the light emitting element is turned on with low brightness, and when the gas leak is detected, the light emitting element is turned on with high brightness.

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