阅读说明：本技术 用于改变报警器报警声音的音量级别的方法及其报警器 (Method for changing volume level of alarm sound of alarm and alarm thereof ) 是由 吴鑫丰 钱志刚 于 2020-11-27 设计创作，主要内容包括：本发明公开了一种用于改变报警器报警声音的音量级别的方法及其报警器,该方法包括：分别检测当前环境的光强和当前环境声音的分贝数；判断光强是否大于第一设定值以及判断分贝数是否大于第二设定值,如果是,则进行设置报警器的报警声音的音量级别为最高级别；如果否,则继续判断光强是否大于第一设定值以及判断分贝数是否不大于第二设定值,如果是,则进行设置报警器的报警声音的音量级别为中上级别；如果否,则继续判断光强是否不大于第一设定值以及判断分贝数是否大于第二设定值,如果是,则进行设置报警器的报警声音的音量级别为中下级别,如果否,则进行设置报警器的报警声音的音量级别为最低级别。本发明可调节报警器的报警声音的音量级别。(The invention discloses a method for changing the volume level of alarm sound of an alarm and the alarm thereof, wherein the method comprises the following steps: respectively detecting the light intensity of the current environment and the decibel number of the sound of the current environment; judging whether the light intensity is greater than a first set value and judging whether the decibel number is greater than a second set value, if so, setting the volume level of the alarm sound of the alarm to be the highest level; if not, continuously judging whether the light intensity is greater than a first set value and judging whether the decibel number is not greater than a second set value, if so, setting the volume level of the alarm sound of the alarm to be an upper-middle level; if not, continuously judging whether the light intensity is not more than a first set value and judging whether the decibel number is more than a second set value, if so, setting the volume level of the alarm sound of the alarm to be a middle-lower level, and if not, setting the volume level of the alarm sound of the alarm to be a lowest level. The invention can adjust the volume level of the alarm sound of the alarm.)

1. A method for changing the volume level of an alarm alert sound comprising the steps of:

respectively detecting the light intensity of the current environment and the decibel number of the sound of the current environment;

judging whether the light intensity is greater than a first set value and judging whether the decibel number is greater than a second set value, if so, setting the volume level of the alarm sound of the alarm to be the highest level;

if not, continuously judging whether the light intensity is greater than a first set value and judging whether the decibel number is not greater than a second set value, if so, setting the volume level of the alarm sound of the alarm to be an upper-middle level;

if not, continuously judging whether the light intensity is not more than a first set value and judging whether the decibel number is more than a second set value, if so, setting the volume level of the alarm sound of the alarm to be a middle-lower level, and if not, setting the volume level of the alarm sound of the alarm to be a lowest level.

2. The method of claim 1, wherein the light intensity of the current environment is detected by a light sensitive resistor and the decibel level of the current environment sound is detected by a microphone.

3. An alarm unit for use with the method of any one of claims 1-2, comprising:

the detection module comprises a light intensity detection mechanism and an environmental sound detection mechanism, wherein the light intensity detection mechanism is used for detecting the light intensity of the current environment, and the environmental sound detection mechanism is used for detecting the decibel number of the current environmental sound;

the control module is electrically connected with the detection module and is used for outputting a corresponding control instruction according to the light intensity detected by the light intensity detection mechanism and the decibel number detected by the environment detection mechanism;

the voice playing module is electrically connected with the control module and is used for receiving the control instruction output by the control module and outputting a corresponding audio signal and audio amplitude according to the control instruction;

the loudspeaker is electrically connected with the voice playing module and is used for playing corresponding sound;

and the power supply module is electrically connected with the detection module, the control module and the voice playing module respectively and is used for providing power supply.

4. The alarm apparatus according to claim 3, wherein the light intensity detecting module comprises a photoresistor R51 and a fixed resistor R50, one end of the fixed resistor R50 is connected with the input voltage, the other end of the fixed resistor R50 is connected with the photoresistor R51, one end of the photoresistor R51 is electrically connected with the control module, and the other end of the photoresistor R51 is grounded.

5. An alarm unit according to claim 3 wherein the ambient sound detection means comprises:

a microphone signal detection circuit for converting a sound signal received by a microphone into an electric signal;

the microphone signal amplifying circuit is electrically connected with the output end of the microphone signal detecting circuit and is used for raising the overall amplitude and level of the acquired electric signal;

and the signal filtering and attenuating circuit is electrically connected with the output end of the microphone signal amplifying circuit and is used for reducing the output voltage and filtering the amplified electric signal.

6. The alarm device according to claim 5, wherein said microphone signal detecting circuit is composed of a resistor R42, a microphone MIC1, a capacitor C54 and a capacitor C52, 2 pins of said microphone MIC1 are grounded, 1 pin of said microphone MIC1 is connected with one end of a resistor R42, the other end of said resistor R42 is connected with an input voltage, one end of said capacitor C54 is connected with 1 pin of said microphone MIC1, the other end of said capacitor C54 is connected with 2 pins of said microphone MIC1, one end of said capacitor C52 is connected with 1 pin of said microphone MIC1, and the other end of said capacitor C52 is connected with an input end of said microphone signal amplifying circuit.

7. The alarm apparatus according to claim 6, wherein said microphone signal amplifying circuit is composed of a resistor R41, a resistor R43, a resistor R46, a resistor R47 and a comparator IC5A, one end of said resistor R43 is connected to said capacitor C52, the other end of said resistor R43 is connected to pin 2 of said comparator IC5A, one end of said resistor R41 is connected to pin 2 of said comparator IC5A, the other end of said resistor R41 is connected to pin 1 of said comparator IC5A, one end of said resistor R46 is connected to the input voltage, the other end of said resistor R46 is connected to pin 3 of said comparator IC5A, one end of said resistor R47 is grounded, and the other end of said resistor R47 is connected to pin 3 of said comparator IC 5A.

8. The alarm apparatus according to claim 7, wherein said signal filtering and attenuating circuit is composed of a resistor R44, a resistor R45 and a capacitor C53, one end of said resistor R44 is connected to pin 1 of said comparator IC5A, the other end of said resistor R44 is connected to one end of said resistor R45 and one end of said capacitor C53, the other end of said resistor R45 is grounded, and the other end of said capacitor C53 is connected to the other end of said resistor R45.

9. The alarm of claim 3, further comprising:

and the ADC analog-to-digital conversion module is respectively electrically connected with the detection module, the power supply module and the control module and is used for converting the analog voltage value output by the detection module into a digital value.

10. The alarm of claim 3, further comprising:

and the audio power amplifier module is respectively electrically connected with the power supply module, the voice playing module and the loudspeaker and is used for receiving the audio signal output by the voice playing module, amplifying the power and then outputting the audio signal to the loudspeaker.

Technical Field

The invention relates to the technical field of automobile alarms, in particular to a method for changing the volume level of alarm sound of an alarm and the alarm.

Background

More and more vehicles are provided with various alarms for reminding people around the vehicles that the vehicles run in the running process of the vehicles. However, the existing alarm gives out sound at a fixed decibel, and gives out a very high decibel alarm sound whenever and under any environment, and is good in the daytime, but the very high decibel alarm sound is noise at night; the noise is good under the condition that the external environment is noisy, but the alarm sound with high decibel is noise under the condition that the external environment is quite quiet, and particularly the life of other people is influenced.

Disclosure of Invention

The invention aims to provide a method for changing the volume level of the alarm sound of an alarm and the alarm thereof, which aim to solve the problem that the existing alarm can sound with a fixed decibel number.

In order to solve the technical problem, one technical solution adopted by the present invention is to provide a method for changing a volume level of an alarm sound of an alarm, including the steps of:

respectively detecting the light intensity of the current environment and the decibel number of the sound of the current environment;

judging whether the light intensity is greater than a first set value and judging whether the decibel number is greater than a second set value, if so, setting the volume level of the alarm sound of the alarm to be the highest level;

if not, continuously judging whether the light intensity is greater than a first set value and judging whether the decibel number is not greater than a second set value, if so, setting the volume level of the alarm sound of the alarm to be an upper-middle level;

if not, continuously judging whether the light intensity is not more than a first set value and judging whether the decibel number is more than a second set value, if so, setting the volume level of the alarm sound of the alarm to be a middle-lower level, and if not, setting the volume level of the alarm sound of the alarm to be a lowest level.

In one embodiment of the invention, the light intensity of the current environment is detected by a photoresistor, and the decibel number of the sound of the current environment is detected by a microphone.

The invention also provides an alarm, which applies the method in any one of the embodiments and comprises the following steps:

the detection module comprises a light intensity detection mechanism and an environmental sound detection mechanism, wherein the light intensity detection mechanism is used for detecting the light intensity of the current environment, and the environmental sound detection mechanism is used for detecting the decibel number of the current environmental sound;

the control module is electrically connected with the detection module and is used for outputting a corresponding control instruction according to the light intensity detected by the light intensity detection mechanism and the decibel number detected by the environment detection mechanism;

the voice playing module is electrically connected with the control module and is used for receiving the control instruction output by the control module and outputting a corresponding audio signal and audio amplitude according to the control instruction;

the loudspeaker is electrically connected with the voice playing module and is used for playing corresponding sound;

and the power supply module is electrically connected with the detection module, the control module and the voice playing module respectively and is used for providing power supply.

In an embodiment of the invention, the light intensity detection module includes a photoresistor R51 and a fixed resistor R50, one end of the fixed resistor R50 is connected to an input voltage, the other end of the fixed resistor R50 is connected to the photoresistor R51, one end of the photoresistor R51 is electrically connected to the control module, and the other end of the photoresistor R51 is grounded.

In one embodiment of the present invention, the ambient sound detection mechanism includes:

a microphone signal detection circuit for converting a sound signal received by a microphone into an electric signal;

the microphone signal amplifying circuit is electrically connected with the output end of the microphone signal detecting circuit and is used for raising the overall amplitude and level of the acquired electric signal;

and the signal filtering and attenuating circuit is electrically connected with the output end of the microphone signal amplifying circuit and is used for reducing the output voltage and filtering the amplified electric signal.

In an embodiment of the present invention, the microphone signal detection circuit is composed of a resistor R42, a microphone MIC1, a capacitor C54, and a capacitor C52, wherein a pin 2 of the microphone MIC1 is grounded, a pin 1 of the microphone MIC1 is connected to an end of the resistor R42, another end of the resistor R42 is connected to an input voltage, an end of the capacitor C54 is connected to a pin 1 of the microphone MIC1, another end of the capacitor C54 is connected to a pin 2 of the microphone MIC1, an end of the capacitor C52 is connected to a pin 1 of the microphone MIC1, and another end of the capacitor C52 is connected to an input terminal of the microphone signal amplification circuit.

In an embodiment of the present invention, the microphone signal amplifying circuit includes a resistor R41, a resistor R43, a resistor R46, a resistor R47, and a comparator IC5A, wherein one end of the resistor R43 is connected to the capacitor C52, the other end of the resistor R43 is connected to the pin 2 of the comparator IC5A, one end of the resistor R41 is connected to the pin 2 of the comparator IC5A, the other end of the resistor R41 is connected to the pin 1 of the comparator IC5A, one end of the resistor R46 is connected to an input voltage, the other end of the resistor R46 is connected to the pin 3 of the comparator IC5A, one end of the resistor R47 is connected to the ground, and the other end of the resistor R47 is connected to the pin 3 of the comparator IC 5A.

In an embodiment of the present invention, the signal filtering and attenuating circuit is composed of a resistor R44, a resistor R45, and a capacitor C53, one end of the resistor R44 is connected to pin 1 of the comparator IC5A, the other end of the resistor R44 is connected to one end of the resistor R45 and one end of the capacitor C53, the other end of the resistor R45 is grounded, and the other end of the capacitor C53 is connected to the other end of the resistor R45.

In one embodiment of the present invention, further comprising:

and the ADC analog-to-digital conversion module is respectively electrically connected with the detection module, the power supply module and the control module and is used for converting the analog voltage value output by the detection module into a digital value.

In one embodiment of the present invention, further comprising:

and the audio power amplifier module is respectively electrically connected with the power supply module, the voice playing module and the loudspeaker and is used for receiving the audio signal output by the voice playing module, amplifying the power and then outputting the audio signal to the loudspeaker.

The invention has the advantages that:

different from the prior art, the method for changing the volume level of the alarm sound of the alarm can simulate a life scene by detecting the light intensity of the current environment and the decibel number of the sound of the current environment during actual use. When the detected light intensity is greater than the first set value and the decibel number is greater than the second set value, the current environment may be daytime and noisy, and the volume level of the alarm sound of the alarm is set to be the highest level, so that the condition that pedestrians cannot hear the alarm sound due to environmental noise can be prevented; when the detected light intensity is greater than a first set value and the decibel number is not greater than a second set value, the current environment may be daytime and quite, and the volume level of the alarm sound of the alarm is set to be at an intermediate level, so that the function of warning pedestrians can be achieved, and the alarm sound can be prevented from being too loud; when the detected light intensity is not more than the first set value and the decibel number is more than the second set value, the current environment may be night and noisy, and the volume level of the alarm sound of the alarm is set to be middle and lower level, so that the alarm sound is not harsh at night, and environmental noise can be prevented from causing pedestrians to be unable to hear clearly; when the detected light intensity is not greater than the first set value and the decibel number is not greater than the second set value, the current environment may be night and quite, the volume level of the alarm sound of the alarm is set to be the lowest level, a general warning effect can be achieved, and noise is not formed to affect the sleep of surrounding residents. So, can the current environment's of intelligent recognition situation to this volume level of adjusting the warning sound of alarm, under the prerequisite that satisfies the warning effect, still do not form the noise.

When the alarm is applied to practical use, the detection module detects the light intensity of the current environment and the decibel number of the sound of the current environment and feeds the light intensity and the decibel number back to the control module, and the control module sends out corresponding pulses according to the light intensity and the decibel number to control the voice playing module to output corresponding audio signals and audio amplitude, and then sends out corresponding sound through the loudspeaker. So, can acquire the light intensity of current environment and the decibel number of current environment sound in real time and according to light intensity and the corresponding audio signal of decibel number output and audio amplitude to can change the decibel number of alarm, avoid the secondary noise pollution to the environment, make people's living environment more comfortable.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic diagram of the steps of a method for changing the volume level of an alarm alert sound in one embodiment of the present invention;

FIG. 2 is a schematic diagram of the construction of an alarm in one embodiment of the present invention;

FIG. 3 is a circuit diagram of the light intensity detection mechanism of the detection module of the alarm in one embodiment of the present invention;

FIG. 4 is a circuit diagram of the ambient sound detection mechanism of the detection module of the alarm in one embodiment of the present invention.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1, in one embodiment of the present invention, a method for changing the volume level of an alarm sound of an alarm is provided, comprising the steps of:

respectively detecting the light intensity of the current environment and the decibel number of the sound of the current environment;

judging whether the light intensity is greater than a first set value and judging whether the decibel number is greater than a second set value, if so, setting the volume level of the alarm sound of the alarm to be the highest level;

if not, continuously judging whether the light intensity is greater than a first set value and judging whether the decibel number is not greater than a second set value, if so, setting the volume level of the alarm sound of the alarm to be an upper-middle level;

if not, continuously judging whether the light intensity is not more than a first set value and judging whether the decibel number is more than a second set value, if so, setting the volume level of the alarm sound of the alarm to be a middle-lower level, and if not, setting the volume level of the alarm sound of the alarm to be a lowest level.

It should be noted that the decibels of the highest level are greater than those of the middle and upper levels, the decibels of the middle and upper levels are greater than those of the middle and lower levels, and the numbers of the middle and lower levels are greater than those of the lowest level. The highest level, the middle upper level, the middle lower level and the lowest level of decibels can be set in advance according to specific situations, for example, the highest level of decibels is 120 decibels, the middle upper level of decibels is 100 decibels, the middle lower level of decibels is 80 decibels, and the lowest level of decibels is 60 decibels.

It should be noted that the first setting value is a light intensity threshold value for distinguishing day and night, the second setting value is a threshold value for distinguishing whether noise interference exists in the environment, and the first setting value and the second setting value can be set in advance according to specific situations.

According to the method for changing the volume level of the alarm sound of the alarm, when the method is in actual use, a living scene can be simulated by detecting the light intensity of the current environment and the decibel number of the sound of the current environment. When the detected light intensity is greater than the first set value and the decibel number is greater than the second set value, the current environment may be daytime and noisy, and the volume level of the alarm sound of the alarm is set to be the highest level, so that the condition that pedestrians cannot hear the alarm sound due to environmental noise can be prevented; when the detected light intensity is greater than a first set value and the decibel number is not greater than a second set value, the current environment may be daytime and quite, and the volume level of the alarm sound of the alarm is set to be at an intermediate level, so that the function of warning pedestrians can be achieved, and the alarm sound can be prevented from being too loud; when the detected light intensity is not more than the first set value and the decibel number is more than the second set value, the current environment may be night and noisy, and the volume level of the alarm sound of the alarm is set to be middle and lower level, so that the alarm sound is not harsh at night, and environmental noise can be prevented from causing pedestrians to be unable to hear clearly; when the detected light intensity is not greater than the first set value and the decibel number is not greater than the second set value, the current environment may be night and quite, the volume level of the alarm sound of the alarm is set to be the lowest level, a general warning effect can be achieved, and noise is not formed to affect the sleep of surrounding residents. So, can the current environment's of intelligent recognition situation to this volume level of adjusting the warning sound of alarm, under the prerequisite that satisfies the warning effect, still do not form the noise.

In the embodiment of the invention, the light intensity of the current environment is detected by adopting the photoresistor, and the decibel number of the sound of the current environment is detected by adopting the microphone.

In the embodiment of the present invention, after detecting the light intensity of the current environment and the decibel number of the sound of the current environment, respectively, the method further includes: the analog voltage value of the light intensity output and the analog voltage value of the sound output are converted into digital values, respectively. Therefore, the control module 3 in the following text is convenient for reading, calculating and judging the light intensity detected by the photoresistor and the sound detected by the microphone.

Referring to fig. 2-4, the present invention also provides an alarm, which applies the method of any of the above embodiments, including: the device comprises a detection module 1, a control module 3, a power module 4, a voice playing module 5 and a loudspeaker 7. The detection module 1 comprises a light intensity detection mechanism and an environment sound detection mechanism, wherein the light intensity detection mechanism is used for detecting the light intensity of the current environment, and the environment sound detection mechanism is used for detecting the decibel number of the current environment sound. The control module 3 is electrically connected with the detection module 1 and is used for outputting a corresponding control instruction according to the light intensity detected by the light intensity detection mechanism and the decibel number detected by the environment detection mechanism. The voice playing module 5 is electrically connected with the control module 3 and is used for receiving the control instruction output by the control module 3 and outputting a corresponding audio signal and audio amplitude according to the control instruction. The speaker 7 is electrically connected with the voice playing module 5 and is used for playing corresponding sound. The power module 4 is electrically connected with the detection module 1, the control module 3 and the voice playing module 5 respectively and used for providing power.

Above-mentioned alarm, during the in-service use, detect the light intensity of current environment and the decibel number of current environment sound and feed back to control module 3 through detection module 1, control module 3 sends corresponding pulse control voice playback module 5 output corresponding audio signal and audio frequency range according to light intensity and decibel number, then sends corresponding sound through speaker 7. So, can acquire the light intensity of current environment and the decibel number of current environment sound in real time and according to light intensity and the corresponding audio signal of decibel number output and audio amplitude to can change the decibel number of alarm, avoid the secondary noise pollution to the environment, make people's living environment more comfortable.

In the embodiment of the invention, the light intensity detection mechanism comprises a photoresistor R51 and a fixed resistor R50, one end of the fixed resistor R50 is connected with an input voltage, the other end of the fixed resistor R50 is connected with a photoresistor R51, one end of a photoresistor R51 is electrically connected with the control module 3, and the other end of the photoresistor R51 is grounded. When the LED lamp is actually used, a fixed voltage division circuit is formed by the fixed resistor R50 and the photoresistor R51, the photoresistor R51 is used for detecting the light intensity of the current environment, and the change of the light intensity enables the resistance value of the photoresistor R51 to change, so that the output light intensity voltage can be changed.

In an embodiment of the present invention, the ambient sound detection mechanism includes a microphone signal detection circuit, a microphone signal amplification circuit, and a signal filtering and attenuation circuit. The microphone signal detection circuit is used for converting a sound signal received by the microphone into an electric signal. Microphone signal amplification circuit is connected with microphone signal detection circuitry's output electricity for carry out the raising of whole range and level with the signal of telecommunication of gathering, the analysis is read to the control module 3 of being convenient for. The signal filtering and attenuating circuit is electrically connected with the output end of the microphone signal amplifying circuit and is used for reducing output voltage, preventing the control module 3 from being burnt out due to overhigh output voltage, and meanwhile, the signal filtering and attenuating circuit is also used for filtering the amplified electric signals and filtering some clutter signals in the acquired electric signals.

In the embodiment, the microphone signal detection circuit is composed of a resistor R42, a microphone MIC1, a capacitor C54 and a capacitor C52, a pin 2 of the microphone MIC1 is grounded, a pin 1 of the microphone MIC1 is connected with one end of a resistor R42, the other end of the resistor R42 is connected with an input voltage, one end of the capacitor C54 is connected with a pin 1 of the microphone MIC1, the other end of the capacitor C54 is connected with a pin 2 of the microphone MIC1, one end of the capacitor C52 is connected with a pin 1 of the microphone MIC1, and the other end of the capacitor C52 is connected with an input end of the microphone signal amplification circuit.

Specifically, in the embodiment, the microphone signal amplifying circuit is composed of a resistor R41, a resistor R43, a resistor R46, a resistor R47 and a comparator IC5A, one end of the resistor R43 is connected with a capacitor C52 of the microphone signal detection circuit, the other end of the resistor R43 is connected with a pin 2 of the comparator IC5A, one end of a resistor R41 is connected with a pin 2 of the comparator IC5A, the other end of the resistor R41 is connected with a pin 1 of the comparator IC5A, one end of the resistor R46 is connected with an input voltage, the other end of the resistor R46 is connected with a pin 3 of the comparator IC5A, one end of the resistor R47 is grounded, and the other end of the resistor R47 is connected with a pin 3 of the comparator IC 5A.

In the embodiment, the signal filtering and attenuating circuit is composed of a resistor R44, a resistor R45 and a capacitor C53, one end of the resistor R44 is connected with pin 1 of a comparator IC5A of the microphone signal amplifying circuit, the other end of the resistor R44 is connected with one end of a resistor R45 and one end of a capacitor C53, the other end of the resistor R45 is grounded, and the other end of the capacitor C53 is connected with the other end of the resistor R45.

In the embodiment of the invention, the alarm further comprises an ADC analog-to-digital conversion module 2, and the ADC analog-to-digital conversion module 2 is electrically connected with the detection module 1, the power supply module 4 and the control module 3, respectively, and is used for converting an analog voltage value output by the detection module 1 into a digital value, so that the control module 3 can read the digital value conveniently.

In an embodiment, the ADC analog-to-digital conversion module 2 uses ADC 0832.

In the embodiment of the invention, the alarm further comprises an audio power amplifier module 6, wherein the audio power amplifier module 6 is respectively electrically connected with the power module 4, the voice playing module 5 and the loudspeaker 7, and is used for receiving the audio signal output by the voice playing module 5, amplifying the power and outputting the audio signal to the loudspeaker 7.

In the embodiment of the invention, the control module 3 adopts a singlechip. Optionally, the single chip microcomputer adopts STM8S003F3P 6.

In the embodiment of the invention, the power module 4 adopts a 24V voltage stabilizing circuit. The 24V voltage regulator circuit can adopt the prior art, and the details are not described herein.

It should be noted that the voice playing module 5, the audio power amplifier module 6, and the speaker 7 may adopt the prior art, and are not described herein again.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.