JP2015158789A - alarm - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alarm capable of performing inspection mode control which is unlikely to be influenced by a temperature and a humidity of a job site environment, by making accuracy of inspection work unlikely to be varied by the concentration of an inspection gas.SOLUTION: An alarm X includes: detection means 10 for detecting a change of an external environment; arithmetic means 20 for calculating an extent of the change of the external environment on the basis of a result detected by the detection means 10; and warning means 30 which issues a warning sound by receiving a warning signal from the arithmetic means 20. The alarm X further includes control means 40 controllable between a detection mode for detecting the change of the external environment and an inspection mode for inspecting an operation of a warning function. The control means 40 sets a warning output variation width that is a reference for issuing warning output for inspection. In the inspection mode, a differential is calculated by subtracting a previous output value that is a detection output value in previous timing, from a present output value that is a detection output value in predetermined timing. If the differential is positive and greater than the warning output variation width, the warning output for inspection is issued.

Description

  The present invention includes a detection unit that detects a change in the external environment, a calculation unit that calculates a degree of change in the external environment based on a result detected by the detection unit, and a change in the external environment in which the calculation unit is equal to or higher than an alarm level. The present invention relates to an alarm device comprising alarm means for receiving an alarm signal from the arithmetic means and generating an alarm sound when it is determined that the alarm is detected.

  In general, it is necessary to check whether a gas alarm operates normally immediately after the start of use or after a certain period of use. The inspection is performed by spraying an actual detection target gas to the gas alarm device or by spraying another gas for inspection.

Patent Document 1 describes an inspection method for a gas alarm device including a semiconductor gas sensor and detection means for detecting gas based on an electrical output of a semiconductor gas sensor in a pulse energized state. The gas alarm device includes inspection detection means for performing inspection detection for an inspection gas different from the detection target gas at a timing different from the main detection timing for the detection target gas. Thereby, since inspection detection is performed at a timing according to the inspection gas, for example, even when a low concentration inspection gas is used, the inspection operation can be performed reliably. As a result, the consumption of inspection gas can be reduced, and the inspection work can be greatly improved.
In the inspection method described in Patent Document 1, the gas detection signal is compared with an alarm level that is a preset threshold for this signal, and an inspection alarm is issued when the gas detection signal exceeds the alarm level. .

  Patent Document 2 discloses a case where the output voltage of the gas sensor to which the inspection gas is sprayed does not exceed the first threshold, and the difference between the output voltage at the current gas detection point and the output voltage at the previous gas detection point. Describes a gas alarm that outputs an alarm that detects the presence of a check gas when the value exceeds a second threshold.

JP 2004-38660 A JP 2008-269533 A

In recent years, in order to improve the selectivity with respect to the gas to be detected, a gas alarm device in which a noble metal catalyst is added to an element of a semiconductor gas sensor has been developed. When such a gas alarm device is inspected using hydrogen as an inspection gas by applying the inspection method described in Patent Document 1, for example, the output of hydrogen, which is an inspection gas, is reduced due to the action of the noble metal catalyst. In some cases, inspection work could not be performed.
On the other hand, if inspection is performed with hydrogen as the inspection gas at a high concentration, recovery of the base output of the semiconductor gas sensor after inspection is delayed, and therefore the timing for shifting to actual gas detection may be delayed.
Also, if the alarm level, which is the threshold set for inspection detection, is reduced without increasing the concentration of hydrogen, which is the inspection gas, it becomes more susceptible to the temperature and humidity of the site environment. When the base output increased due to the influence, the inspection alarm was issued even though the inspection gas was not blown, and the inspection work could not be performed accurately.

Further, in the gas alarm device described in Patent Document 2, since the output difference is calculated at a timing synchronized with the voltage cycle, in order to avoid the influence of the temperature and humidity in the field environment even though the output difference becomes small. In this case, the second threshold value needs to be set large, and the difference in output voltage does not reach the second threshold value, so that the inspection work may not be performed accurately.
In addition, the second threshold value can be set small so that inspection can be performed even if the output difference is small, but in this case, there is a possibility that false alarms may occur due to base fluctuation due to temperature and humidity fluctuations, and accurate inspection work is performed. It was difficult.
Further, in the gas alarm device described in Patent Document 2, since the alarm is issued not only when the output difference is positive but also when it is negative, the base output is not stabilized during the standby mode such as immediately after the power is turned on, for example. In the case of further decrease, there is a possibility that an inspection alarm is issued before the inspection gas is blown.

  Accordingly, an object of the present invention is to provide an alarm device capable of controlling the inspection mode in which the accuracy of the inspection work is not easily changed by the concentration of the inspection gas and is hardly affected by the temperature and humidity in the field environment.

  In order to achieve the above object, an alarm device according to the present invention includes a detection unit that detects a change in an external environment, a calculation unit that calculates a degree of a change in the external environment based on a result detected by the detection unit, An alarm device comprising: an alarm means that receives an alarm signal from the arithmetic means and emits an alarm sound when it is determined that a change in the external environment above the alarm level is detected by the arithmetic means; Comprises control means capable of switching to a detection mode for detecting a change in the external environment and an inspection mode for inspecting the operation of the alarm function, and the control means is a reference for issuing an inspection alarm output which is an output for inspection. In the inspection mode, the output of the detection means is measured and stored in a predetermined cycle, and the current output that is a detection output value at a predetermined timing is set. From this, the difference is calculated by subtracting the previous output value which is the detection output value at the timing immediately before that, and when the difference is positive and larger than the alarm output change width, the inspection alarm output is issued. .

  According to this configuration, since the difference between the current output value and the previous output value is compared with the alarm output change width, the operation of the alarm function is checked by looking at the fluctuation of the output width of the output value of the detection means. be able to. In particular, in this configuration, since the difference between the output values acquired at two adjacent timings is detected, it is considered that the tendency of the difference does not depend on the density of the inspection gas. Therefore, in the alarm device of the present invention, it is possible to prevent the accuracy of inspection work from fluctuating due to the concentration of the inspection gas, and further, compared to the case where it is determined whether the output value of the detection means exceeds a specific threshold value. In addition, since it can be made less susceptible to the influence of temperature and humidity in the field environment, it is possible to prevent false reports during inspection work.

  In addition, since the alarm output for inspection is issued only when the difference is positive in this configuration, even if the base output does not stabilize immediately after the power is turned on, and the base output further decreases, an erroneous report during inspection work is generated. Can be prevented. Therefore, when the difference is positive and larger than the alarm output change width, the alarm device of the present invention that issues an inspection alarm output is less susceptible to temperature and humidity fluctuations and can perform a highly reliable inspection. .

  The second characteristic configuration of the alarm device according to the present invention is that the previous output value is an initial output value obtained by measuring a detected output value when the inspection mode is entered or immediately before the inspection mode is entered.

  Since the initial output value is a detection output value when the inspection mode is entered or immediately before the inspection mode is entered, the initial output value can be an initial value in the inspection mode. That is, in the inspection mode, the initial output value and the output value of the detection means acquired thereafter can be compared by the control means, and the magnitude relationship between the initial output value and the output value of the detection means can be monitored.

  The third characteristic configuration of the alarm device according to the present invention is that, when the driving method is pulse driving, the detection pulse is shorter in the inspection mode than in the detection mode.

  According to this configuration, the inspection mode can be performed with the sensitivity improved by shortening the detection pulse time.

It is the schematic of the alarm device of this invention. It is a figure which shows the control flow at the time of inspection mode.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the alarm device X of the present invention includes a detection unit 10 that detects a change in the external environment, and a calculation unit 20 that calculates the degree of change in the external environment based on the result detected by the detection unit 10. And an alarm means 30 that receives an alarm signal from the arithmetic means 20 and emits an alarm sound when it is determined that the arithmetic means 20 has detected a change in the external environment at or above the alarm level, and detects a change in the external environment The control means 40 which can be switched to the inspection mode which checks operation | movement of the detection mode to perform and an alarm function is provided.

(Detection means)
As the detection means 10, for example, any one of a city gas sensor, an LP gas sensor, and a CO sensor may be provided. A city gas sensor can detect a leak gas such as hydrocarbon gas, an LP gas sensor can detect LP gas, and a CO sensor can detect carbon monoxide gas generated by incomplete combustion. A type sensor element or a catalytic combustion type gas sensor element can be used. This embodiment demonstrates the case where it is set as the alarm device X as the gas alarm device which applied the semiconductor type sensor as the detection means 10. FIG.

(Calculation means)
The computing unit 20 includes a concentration calculation unit that calculates the detected gas concentration based on the output of the detection unit 10 detecting the leakage of the detected gas. The concentration calculation unit may use a microcomputer that can calculate the city gas concentration based on the output signal from the detection means 10.

  The calculating means 20 controls the alarm means 30 to send an alarm signal S1 to the alarm means 30 and issue an alarm by the alarm means 30 when the detecting means 10 continuously detects the city gas concentration above the alarm level.

(Alarm means)
When the calculation means 20 determines that the detection means 10 has continuously detected the detected gas concentration equal to or higher than the alarm level, the warning means 30 receives the warning signal S1 from the calculation means 20 and issues a warning by voice. In the present embodiment, the alarm means 30 is constituted by a speaker and its drive circuit, and converts an alarm sound signal S2 from the storage means 50 described later into an alarm sound S3 and outputs it.

(Control means)
The control unit 40 includes a storage unit 50 that stores the output of the detection unit 10. As long as the memory | storage means 50 is a memory and storage which can memorize | store the output of the detection means 10, and several types of alarm sound signals, what kind of aspect may be sufficient as it. As a multiple types of alarm sound signals, for example, a synthesized sound signal required for a home gas alarm device (for example, a synthesized voice such as “Does gas leak?”), Required for a commercial gas alarm device Two types of electronic sound signals (for example, electronic sounds such as “beep, beep, beep, beep”) may be stored. The number of alarm sound signals to be stored may be two or more, and the forms of synthesized speech and electronic sound may be other than the above.

  The control means 40 is connected to a power switch section 60 that can switch the alarm device X on and off, an inspection switch section 70 that performs an inspection operation for confirming whether the alarm means 30 operates normally, and the like.

The control means 40 can be switched to a detection mode for detecting a change in the external environment and an inspection mode for inspecting the operation of the alarm function. That is, when the operator turns on the inspection switch unit 70, the driving of the alarm device X is switched from the detection mode to the inspection mode.
In the detection mode, the gas to be detected is detected by detecting the electric resistance value of the sensitive layer of the semiconductor sensor element by the calculation means 20. The detection time of the electric resistance value is different in the detection mode and the inspection mode. The alarm device X of the present invention may be driven by either continuous driving or pulse driving. For example, in the case of pulse driving, the detection time (detection pulse) in the detection mode is 2.5 seconds, The detection time is set to 0.9 seconds. In the present embodiment, when the detection mode is switched to the inspection mode, the control means 40 performs control to shorten the detection pulse of the electrical resistance value. On the other hand, when the inspection mode is switched to the detection mode, the control means 40 performs control to lengthen the detection time of the electrical resistance value.

  In addition, when the inspection switch unit 70 is not turned on, the control unit 40 operates as the inspection mode for a predetermined period after starting the operation of the alarm device X, and operates as the detection mode after the predetermined period elapses. Then, control may be performed to automatically switch from the inspection mode to the detection mode after the predetermined period has elapsed. The predetermined period may be measured by a timer or the like built in the control means 40.

  The control means 40 sets a predetermined alarm output change width that is a reference for issuing an inspection alarm output that is an inspection output. The alarm output change width is stored in the storage unit 50 by appropriately setting a desired change width.

  Further, in the inspection mode, the control means 40 measures and stores the output of the detection means 10 at a predetermined cycle, and from the current output value that is the detection output value at a predetermined timing, the detection output at the immediately preceding timing. The difference is calculated by subtracting the previous output value, which is a value, and if the difference is positive and greater than the alarm output change width, control is performed so as to issue an inspection alarm output.

  The output of the detection means 10 is memorize | stored in the memory | storage means 50 whenever it measures the sprayed inspection gas. Thus, the storage unit 50 stores the current output value and the previous output value, and the control unit 40 calculates the difference between them. When the difference is positive, the control means 40 compares this difference with a preset alarm output change width, and controls to issue an inspection alarm output when the difference is larger than the alarm output change width. For the inspection alarm output, for example, an alarm sound signal stored in the storage means 50 may be output.

  In this way, by comparing the difference between the current output value and the previous output value and the alarm output change width, the operation of the alarm function can be checked by looking at the fluctuation in the output width of the output value of the detection means 10. . In particular, in this aspect, since the difference between the output values acquired at two adjacent timings is detected, it is considered that the tendency of the difference does not depend on the density of the inspection gas. Therefore, in the alarm device X of the present invention, it is possible to prevent the accuracy of the inspection operation from fluctuating due to the concentration of the inspection gas, and to determine whether the output value of the detection means 10 exceeds a specific threshold value. Compared to, it can be made less susceptible to the temperature and humidity of the field environment. In addition, since the alarm device X of the present invention issues an inspection alarm output only when the difference is positive, even if the base output is further lowered even after the power is turned on, the base output is not stabilized. This prevents false alarms during inspection work.

  The initial previous output value may be an initial output value obtained by measuring the detected output value when entering the inspection mode or immediately before entering the inspection mode.

  Since the initial output value is a detection output value when the inspection mode is entered or immediately before the inspection mode is entered, the initial output value can be an initial value in the inspection mode. That is, in the inspection mode, the control unit 40 compares the initial output value and the output value of the detection unit 10 acquired thereafter, and monitors the magnitude relationship between the initial output value and the output value of the detection unit 10. In the alarm device X of the present invention, if the difference between the output values is not positive, the inspection alarm output is not performed. Therefore, when the initial output value is larger than the output value of the detection means 10 acquired thereafter, that is, the output is unstable. Therefore, it is possible to prevent an alarm output for inspection from being issued.

  In the inspection mode, the calculation means 20 may control the alarm means 30 not to issue an alarm even when the detection means 10 continuously detects the city gas concentration equal to or higher than the alarm level. By controlling in this way, in the inspection mode, an alarm is issued only by the difference between the output values acquired at two adjacent timings, so that false alarms due to an increase in base output due to temperature and humidity can be prevented, and the base output has increased. Even if it is, accurate inspection can be performed.

FIG. 2 shows a control flow in the inspection mode in the alarm device X of the present invention.
The alarm device X was applied with a semiconductor sensor as the detection means 10 and was driven at 2.3 V for 2.5 seconds on and 7.5 seconds off (period of 10 seconds). The inspection gas was hydrogen (3000 ppm). In the control means 40, an alarm output change width is set in advance. In this embodiment, the alarm output change width is set to be a sensitivity output corresponding to 500 to 1000 ppm of methane.

First, the power switch unit 60 is operated to turn on the alarm device X, and the inspection switch unit 70 is operated to start the inspection mode (# 1). At this time, the initial output value is measured. At this time, the time from when the power is turned on or the operation of the inspection switch unit 70 is measured by a timer built in the alarm device X (# 2).
In this aspect, a case where the inspection mode is set to 3 minutes will be described. If it is less than 3 minutes from the start of the inspection mode (# 3), the output of the detection means 10 is measured at a cycle of 10 seconds (# 4).
The difference is calculated by subtracting the previous output value from the current output value from the time point (# 5) when 20 seconds have elapsed from the start of the inspection mode (# 6).
It is determined whether or not the difference exceeds the warning output change width (# 7).
If the difference is positive and greater than the alarm output change width, an inspection alarm output is issued (# 8), and then an end process is performed (# 11).

  When 3 minutes have elapsed from the start of the inspection mode, the timer is reset (# 9), the output of the detection means 10 in the storage means 50 is reset (# 10), and the end process is performed (# 11).

  The present invention includes a detection unit that detects a change in the external environment, a calculation unit that calculates a degree of change in the external environment based on a result detected by the detection unit, and a change in the external environment in which the calculation unit is equal to or higher than an alarm level. When it is determined that an alarm has been detected, the alarm device can be used for an alarm device including alarm means for receiving an alarm signal from the arithmetic means and generating an alarm sound.

X alarm device 10 detection means 20 calculation means 30 alarm means 40 control means

Claims (3)

Detection means for detecting changes in the external environment;
Calculation means for calculating the degree of change in the external environment based on the result detected by the detection means;
In an alarm device comprising: an alarm means for receiving an alarm signal from the arithmetic means and generating an alarm sound when it is determined that the arithmetic means has detected a change in the external environment at or above an alarm level,
Control means that can be switched to a detection mode for detecting changes in the external environment and an inspection mode for checking the operation of the alarm function,
The control means includes
A predetermined alarm output change range that is a reference for issuing an inspection alarm output, which is an output for inspection, is set.
In the inspection mode, the output of the detection means is measured and stored at a predetermined cycle,
A difference is calculated by subtracting the previous output value, which is the detection output value at the immediately preceding timing, from the current output value, which is the detection output value at a predetermined timing, and when the difference is positive, and from the alarm output change width An alarm that emits an alarm output for inspection when it is large.   The alarm device according to claim 1, wherein the previous output value is an initial output value obtained by measuring a detection output value when the inspection mode is entered or immediately before the inspection mode is entered.   3. The alarm device according to claim 1, wherein when the driving method is pulse driving, the detection pulse is shorter in the inspection mode than in the detection mode.

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