CN209803960U

CN209803960U - Smoke alarm

Info

Publication number: CN209803960U
Application number: CN201920376106.XU
Authority: CN
Inventors: 徐承柬; 龚大国; 陈骋; 李晓龙; 郭张乐; 朱能辉; 黄振川
Original assignee: Wenzhou Lian An Internet Of Things Technology Co Ltd
Current assignee: Wenzhou Lian'an Electronic Equipment Co ltd
Priority date: 2019-03-25
Filing date: 2019-03-25
Publication date: 2019-12-17
Anticipated expiration: 2029-03-25

Abstract

The utility model relates to a smoke detector alarm, which comprises a shell and a circuit board arranged in the shell, wherein the circuit board comprises a microcontroller module, a smoke detector module, an alarm module and an ultrasonic module, when the smoke detector module detects that the indoor smoke concentration exceeds a threshold value, the ultrasonic module starts to continuously detect a preset monitoring space for preset times, and ultrasonic data including echo time and an echo intensity value corresponding to the echo time are obtained; and sending an alarm signal when the peak value change, the fluctuation frequency and the fluctuation amplitude in the ultrasonic data exceed preset conditions. The utility model discloses added the ultrasonic wave function on the basis of alarm is felt to current cigarette, when the smog concentration that the module detected is felt to the cigarette exceeded the threshold value, opened the ultrasonic wave module and detected and further judge the smog and flow the violent degree condition, through the smog condition judgement method of two kinds of different modes, combine advantage between them, make final smog warning rate of accuracy higher, reduce the emergence of the wrong report condition.

Description

Smoke alarm

Technical Field

the invention relates to the field of smoke alarm, in particular to a smoke alarm and a fire detection method.

Background

The existing smoke alarm realizes fire prevention by monitoring the concentration of smoke, is widely applied to various fire alarm systems, and can immediately send out audible and visual alarm and signal alarm when detecting that the concentration of the smoke exceeds a threshold value.

Mainstream photoelectric smoke detector alarm, its smog concentration detects and is based on the light scattering principle: the infrared beam of the infrared emission tube can be scattered by smoke particles, and the intensity of scattered light is in direct proportion to the concentration of smoke. When smoke exists in the environment, smoke particles enter the labyrinth to scatter the infrared light emitted by the emitting tube, the intensity of scattered light and the smoke concentration have a certain linear relation, the subsequent sampling circuit changes, a main control chip arranged in the alarm judges the smoke concentration according to the intensity of the scattered light to confirm whether a fire alarm occurs, once the smoke concentration exceeds an alarm threshold value, the alarm sends a fire alarm signal, a fire indicator lamp is lightened, and a buzzer is started to give an alarm. The smoke alarm is characterized by high sensitivity and can detect only smoke with slight concentration.

The biggest problem of the existing smoke alarm in use is the false alarm problem. The smoke-sensitive alarm detects the smoke concentration by a light scattering principle, the intensity of scattered infrared light has a certain linear relation with the smoke concentration, particularly, when the smoke concentration is below a certain value, the intensity of scattered light is in a direct proportion relation with the smoke concentration, however, after the smoke concentration exceeds the value, the intensity of the scattered light rises to a small extent and does not rise any more, namely, a limit value exists on the smoke concentration value detected by the photoelectric smoke-sensitive alarm, and when the smoke concentration exceeds the limit value, the alarm cannot detect the smoke concentration, and a common manufacturer sets the smoke concentration alarm threshold of the smoke-sensitive alarm to be closer to the limit value in order to reduce false alarm.

The practical alarm has complex and changeable use environment, the smoke concentration in a room can temporarily increase to a certain concentration value and then fall back or be maintained at the certain concentration value for a long time due to reasons of smoking, cooking and the like of a user, the smoke concentration value often exceeds an alarm threshold value set by a common alarm, and therefore the conventional photoelectric smoke-sensitive alarm can generate false alarm due to inherent limitation.

Of course, there are other reasons for the false alarm, for example, the alarm may accumulate dust after being used for a long time, or a small bug may enter the alarm, or the maze is deformed, and the actual smoke concentration value does not reach the preset concentration value, and then the alarm is given.

Disclosure of Invention

In order to avoid the defects of the background art, the invention provides a smoke detector alarm which can assist in judging whether a fire disaster occurs or not by detecting the intensity of smoke flowing, and simultaneously provides a fire detection method applied to the smoke detector alarm.

The invention provides a smoke alarm, which comprises a shell and a circuit board arranged in the shell, wherein the circuit board comprises a microcontroller module, a smoke sensing module and an alarm module, wherein the smoke sensing module and the alarm module are connected with the microcontroller module; when the peak value change, the fluctuation frequency and the fluctuation amplitude in the ultrasonic data exceed the preset conditions, the microcontroller module controls the alarm module to send an alarm signal.

Furthermore, the side surface of the housing has at least two through holes with different directions, the ultrasonic module includes ultrasonic transmitting and receiving probes which are fixedly installed in the through holes and are obliquely oriented downward, and the number of the through holes and the corresponding ultrasonic transmitting and receiving probes is preferably 3.

Furthermore, the ultrasonic module also comprises a fixed sleeve and a silica gel sleeve, and the ultrasonic transceiving probe is fixedly embedded into the silica gel sleeve; the silica gel sleeve is fixedly embedded into the fixed sleeve; the fixing sleeve is fixedly embedded into the through hole on the side surface of the shell.

Further, the device also comprises a mounting plate; the top surface of the shell is provided with a plurality of convex buckles with T-shaped sections, the mounting plate is provided with through holes correspondingly matched with the convex buckles, and the convex buckles can pass through the through holes and then can be fixedly matched with the mounting plate by rotating the shell.

Furthermore, the circuit board also comprises an acceleration module connected with the microcontroller module, and the acceleration module is used for judging the motion condition of the smoke detector alarm by detecting the change of the acceleration; when the change of the acceleration exceeds a threshold value, the microcontroller module controls the alarm module to send an alarm signal.

Furthermore, the alarm module is a wireless communication alarm module or/and a sound and light alarm module; the microcontroller module can control the sound-light alarm module to send sound-light alarm to inform surrounding personnel, and the microcontroller module can control the wireless communication alarm module to send wireless alarm signals to inform a matched data platform.

The invention also provides a fire detection method, which comprises the following steps:

Acquiring smoke concentration data in the current environment;

determining that the smoke concentration exceeds a threshold;

Acquiring ultrasonic data detected by a preset number of continuous times in a preset monitoring space, wherein the ultrasonic data comprises echo time and an echo intensity value corresponding to the echo time;

And judging whether the peak value change, the fluctuation frequency and the fluctuation amplitude in the ultrasonic data exceed preset conditions, and if so, judging that the fire disaster happens in the current environment.

Further, the step of judging whether the peak value change, the fluctuation frequency and the fluctuation amplitude in the ultrasonic data exceed the preset conditions includes:

Determining that the fluctuation amplitude of the upper and lower peak values corresponding to the same echo time point in the ultrasonic data exceeds a preset condition as abnormal fluctuation;

And judging whether the frequency of the abnormal fluctuation exceeds a preset frequency, and if so, judging that the smoke flow intensity of the preset monitoring space exceeds a fire alarm threshold.

Further, the method further comprises the following steps: and judging whether the frequency of the abnormal fluctuation falls back after exceeding a preset frequency, and whether the attenuation degree of the peak value of the normal peak in the ultrasonic data exceeds a threshold value, if so, judging that the smoke in the preset monitoring space is completely diffused.

further, the method further comprises the following steps:

Determining a reflection strong point and an echo time point corresponding to the reflection strong point according to a peak value of a normal peak in ultrasonic data;

Comparing the ultrasonic data detected by the latest wheel with the ultrasonic data detected by the first wheel;

screening and determining the same reflection intensity points in the two rounds of ultrasonic data;

And judging whether the variation of the echo time points corresponding to the same reflection strong points exceeds a threshold value, and if so, judging that the temperature rise of the preset monitoring space is abnormal.

Further, the step of determining that the fluctuation amplitude of the peak value of the wave peak corresponding to the same echo time point in the ultrasonic data exceeds a preset condition is abnormal fluctuation comprises:

determining an effective peak value and a corresponding echo time point in the ultrasonic data detected each time, wherein the effective peak value is a peak value exceeding a preset critical echo intensity value;

Integrating the ultrasonic data of each time, determining a maximum effective peak value and a minimum effective peak value corresponding to each echo time point, and if the effective peak value appears only once at a certain echo time point, defaulting the minimum effective peak value to a preset critical echo intensity value;

Determining the fluctuation ratio of the maximum effective peak value and the minimum effective peak value of each echo time point;

And determining that abnormal fluctuation exists at the echo time point with the fluctuation ratio larger than the preset ratio.

The invention also provides a smoke flow intensity detection method based on ultrasonic waves, which comprises the following steps:

the severity of the flow of smoke in the predetermined monitored space is determined based on the frequency of the abnormal fluctuation.

The invention also provides an ultrasonic smoke sensing device, which comprises a memory for storing a program and a processor for executing the program, wherein the program is executed by the processor to realize the steps of the fire detection method or the smoke flow intensity detection method based on the ultrasonic wave.

The smoke detection alarm has the advantages that the ultrasonic function is added on the basis of the existing smoke detection alarm, when the smoke concentration detected by the smoke detection module exceeds a threshold value, the alarm only enters an early warning state, then the ultrasonic module is started to detect and further judge the smoke flow intensity condition, and when the fluctuation frequency and the fluctuation amplitude of ultrasonic data exceed preset conditions, the alarm can send an alarm signal; by adopting two smoke condition judgment methods with different modes and combining the advantages of the two methods, the final smoke alarm accuracy is higher, and the occurrence of false alarm conditions is reduced.

Drawings

Fig. 1 is an exploded view of a smoke detector alarm according to embodiment 1 of the present invention.

fig. 2 is a schematic perspective view of a smoke detector alarm according to embodiment 1 of the present invention.

Fig. 3 is a schematic view of a module composition of a circuit board of the smoke detector alarm in embodiment 1 of the present invention.

fig. 4-6 are schematic diagrams of waveforms captured in ultrasound data acquired in a smoke-free environment in an experimental scenario.

Fig. 7-9 are schematic diagrams of waveforms captured in ultrasound data acquired in a low concentration smoke environment in this experimental scenario.

Fig. 10-12 are schematic diagrams of waveforms captured in ultrasound data acquired in a high concentration smoke environment in this experimental scenario.

Fig. 13 is a flowchart schematically illustrating a fire detection determination method according to embodiment 2 of the present invention.

Fig. 14 is a flowchart schematically showing a method of determining abnormal fluctuation in the fire detection judging method according to embodiment 2 of the present invention.

fig. 15 is a flowchart illustrating a further auxiliary determination method in the fire detection determination method according to embodiment 2 of the present invention.

Fig. 16 is a flowchart illustrating a second further auxiliary judgment method in the fire detection judgment method according to embodiment 2 of the present invention.

fig. 17 is a schematic flow chart of a smoke flow intensity detection method based on ultrasonic waves in embodiment 3 of the present invention.

The reference numbers are as follows: 1-a base; 2-a circuit board; 2 a-a microcontroller module; 2 b-a sound and light alarm module; 2 c-a wireless communication module; 2 d-acceleration module; 3-a smoke sensing module; 4, covering the upper cover; 5-a battery; 6-battery compartment cover; 7-mounting a plate; 8-an ultrasonic module; 8 a-ultrasonic transceiver probe; 8 b-a silica gel sleeve; 8 c-fixing sleeve.

Detailed Description

The invention is further described below with reference to the accompanying drawings and specific examples.

embodiment 1, referring to fig. 1 to 3, a smoke alarm is integrally disc-shaped and includes a housing, a battery 5, and a circuit board 2 disposed inside the housing; the shell comprises a base 1, an upper cover 4 and a battery chamber cover 6 which are mutually matched and installed, and the side surface of the base 1 is provided with three through holes with different directions and a smoke inlet and outlet channel; the circuit board 2 comprises a microcontroller module 2a, a smoke sensing module 3 connected with the microcontroller module 2a, an audible and visual alarm module 2b, a wireless communication module 2c and an ultrasonic module 8; the ultrasonic module 8 comprises an ultrasonic transceiving probe 8a, a silica gel sleeve 8b and a fixed sleeve 8c, the ultrasonic transceiving probe 8a is fixedly embedded in the silica gel sleeve 8b, the silica gel sleeve 8b is fixedly embedded in the fixed sleeve 8c, the fixed sleeve 8c is fixedly arranged in the through hole, and the direction of the ultrasonic transceiving probe 8a faces obliquely downwards; the silica gel sleeve 8b is used for absorbing air vibration generated by sound and avoiding interference among the ultrasonic receiving and transmitting probes 8 a; when the smoke sensing module 3 detects that the indoor smoke concentration exceeds the threshold value, the microcontroller module 2a controls the ultrasonic module 8 to start continuous multiple detection of the preset monitoring space, and ultrasonic data including echo time and an echo intensity value corresponding to the echo time are obtained; when the peak value change, the fluctuation frequency and the fluctuation amplitude in the ultrasonic data exceed the preset conditions, the microcontroller module 2a controls the sound-light alarm module 2b to send out sound-light alarm and controls the wireless communication module 2c to send out alarm signals.

The traditional ultrasonic ranging device can only detect whether reflected ultrasonic waves exist or not after transmitting the ultrasonic waves, namely reflected echoes, and based on the principle, when the ultrasonic transmitter transmits the ultrasonic waves to a certain direction, timing is started at the same time of transmitting time, the ultrasonic waves are transmitted in the air and return immediately when encountering an obstacle in the process, the ultrasonic receiver immediately stops timing after receiving the reflected echoes to obtain echo time, and the distance between the ultrasonic ranging device and a nearest object can be calculated according to a sound velocity and echo time formula. The ultrasonic device adopted in the invention can also detect the intensity value of the reflected ultrasonic wave, namely the echo intensity value on the basis, when the ultrasonic transmitter transmits the ultrasonic wave to a certain object, and the ultrasonic receiver does not stop timing when receiving the reflected echo, so as to obtain the echo intensity value and the echo time; because the ultrasonic wave has a large beam angle, a plurality of reflection points capable of reflecting the ultrasonic wave may exist on the surface of an object within the beam angle range, and the distance between the reflection points and the ultrasonic wave device is large or small, the ultrasonic wave device can continuously detect the echo intensity value corresponding to the echo time along with the increase of the echo time. The magnitude of the echo intensity value depends on the total number of reflection points at the same reflection distance (or the same echo time).

For convenience of understanding, fig. 4 is taken as an example, the obtained echo time is taken as a horizontal axis (the horizontal axis in the figure of the present invention is actually the reflection distance converted from the echo time, because the echo time is generally in the order of milliseconds, if the echo time is taken as the horizontal axis, a person generally has no intuitive concept on the too small time data in the figure and is difficult to understand, and the time is converted into the reflection distance and is more intuitive and easy to understand by others), and the echo intensity value is taken as the vertical axis to form a visible and intuitive waveform diagram. When the ultrasonic wave device transmits ultrasonic waves to an object existing in a preset background environment, due to factors such as the angle, the shape and the size of the object, echoes are easily formed at certain areas, such as the ground, the wall corner, the right angle formed by a door and the ground and the like under the device, so that wave peaks of echo intensity values appear at echo time positions corresponding to the areas in a oscillogram, the corresponding peak values of the wave peaks are reflection intensity points in the preset background environment under the normal condition, and if the preset background environment does not change, the reflection intensity points cannot change; and certain area parts do not or rarely form echoes, so that the echo intensity value at the echo time corresponding to the area parts in the oscillogram tends to zero.

assuming that the background environment of the ultrasonic device is stable and unchanged when the ultrasonic device is turned on, referring to fig. 4-6, the trends of the oscillograms after the ultrasonic data is acquired are also basically the same, only because of the characteristics of the ultrasonic waves, the echo intensity values corresponding to the same echo time in the data acquired for multiple times fluctuate up and down, but the fluctuation amplitude is relatively small, and the fluctuation can be calculated within the normal fluctuation deviation range. However, when smoke exists in the environment and the smoke spreads in the flow, referring to fig. 7-9, the fluctuation of the echo intensity value exceeds the normal fluctuation deviation range, which is embodied by a large peak in fig. 7 which is far larger than the average value in the normal environment and a small peak in fig. 8 which is far smaller than the average value in the normal environment. Along with the rise of the smoke concentration and the flow intensity, the fluctuation frequency and the fluctuation amplitude of the echo intensity value are respectively accelerated and increased; overall at higher smoke concentrations, the most obvious variation that can be shown with reference to fig. 10-12 is that small peaks will also appear in the areas where there is no echo intensity value peak in fig. 4-6; in contrast, the original large peak region does not reach the average peak value in the absence of smoke in most oscillograms. These situations arise because smoke particles flowing in the air affect the reflection of the ultrasonic waves. By means of calculation and analysis of the ultrasonic data, namely, by means of analysis and calculation of peak-to-peak changes, fluctuation frequency and fluctuation amplitude in the ultrasonic data, the smoke flow intensity can be roughly inferred. It should be noted that, in practical tests, the applicant found that the air conditioner, the blowing fan generated by the electric fan, and the heat flow generated by the heater also cause interference fluctuation of the ultrasonic data, but obviously, the interference caused by the smoke is not serious, so that the situations can be completely ignored in the embodiment.

In the initial stage of fire, the stage is characterized by large smoke at the beginning, rapid smoke diffusion, small combustible substance combustion area, low flame, low radiant heat and slow fire development, and the stage is the best time for fire extinguishing. According to the characteristics of the early stage of fire, the embodiment of the invention adds the ultrasonic function on the basis of the existing smoke-sensitive alarm, when the smoke concentration detected by the smoke-sensitive module 3 exceeds a threshold value, the alarm only enters an early warning state, and then the ultrasonic module 8 is started to detect and further judge the smoke condition. The three ultrasonic transceiving probes 8a facing different directions detect monitoring spaces in respective directions, and when the peak value change, the fluctuation frequency and the fluctuation amplitude in the ultrasonic data are judged to exceed preset conditions in one direction, the fact that dense smoke flows violently in the monitoring space in the direction is indicated, and an alarm can send an alarm signal; by adopting two smoke judgment methods with different modes, the final smoke alarm accuracy is higher, and the occurrence of false alarm is reduced.

In a certain sense, the intensity of smoke flowing is more accurate than the smoke concentration in judging fire, when the fire just starts, smoke can be continuously generated, and the newly generated smoke has extremely high concentration and can be raised at the initial generation stage and quickly diffused in the air, so that the disturbance of the smoke to the air is the highest; if the fire is extinguished, the smoke can be cut off, new smoke is not generated at the time, old smoke is diluted by air, the flow speed is gradually reduced, and the disturbance to the air is also gradually reduced; in the whole process, the existing smoke detector alarm can only obtain that the smoke concentration exceeds a threshold value, but cannot judge the development condition of a fire. In addition, since smoke spreads from the ignition point to the vicinity, the direction of the origin of smoke and diffusion can be detected by detecting the ultrasonic data in three directions.

This embodiment smoke detector alarm still includes mounting panel 7, and the shell top surface is equipped with a plurality of cross-sections and is the protruding knot of "T" font, is equipped with on the mounting panel 7 to correspond the complex through-hole with protruding knot, and protruding knot passes behind the through-hole accessible rotating housing makes shell and mounting panel 7 fixed coordination, easy to assemble and dismantles and change battery 5.

the circuit board 2 further comprises an acceleration module 2d connected with the microcontroller module 2a, and the acceleration module 2d is used for judging the motion condition of the smoke alarm by detecting the change of the acceleration; when the change of the acceleration exceeds the threshold value, the microcontroller module 2a controls the sound-light alarm module 2b to send out sound-light alarm and controls the wireless communication module 2c to send an anti-disassembly movement alarm signal.

embodiment 2, referring to fig. 13, a fire detection determination method applied to the smoke detector alarm of embodiment 1 includes:

s101, smoke concentration data under the current environment are obtained.

S102, judging whether the smoke concentration exceeds a threshold value, if so, entering the next step; the first two steps are smoke concentration judgment processes of common smoke feeling, whether fire disaster conditions possibly occur in the current environment can be judged through various existing smoke concentration judgment methods, and in order to prevent false alarm, if the smoke concentration exceeds a threshold value, an early warning state is only started, and an environmental smoke condition verification result is detected again by adopting a smoke condition detection method based on ultrasonic waves.

S103, acquiring ultrasonic data detected by a preset number of continuous times in a preset monitoring space, wherein the ultrasonic data comprises echo time and an echo intensity value corresponding to the echo time; in this embodiment, the ultrasonic data obtained by continuous preset times of detection is defined as one round of ultrasonic data, the number of times in each round of ultrasonic data directly affects the screening result of abnormal fluctuation, and the more times each group is, the more abnormal fluctuation is in the round under the same condition.

S104, determining that the fluctuation amplitude of the upper and lower peak values corresponding to the same echo time point in the ultrasonic data exceeds a preset condition as abnormal fluctuation; the step is the core of the method, if the upper and lower amplitudes of the echo intensity value at the same echo time point in one round of ultrasonic data are large, it is indicated that the detection of the ultrasonic wave is influenced by the serious disturbance factor appearing in the current air, and the factor is smoke; the most obvious amplitude change is the peak value of each peak, and when the fluctuation amplitude of the peak value of each peak exceeds a certain degree, the peak value can be considered as abnormal fluctuation caused by smoke.

s105, judging whether the frequency of the abnormal fluctuation exceeds a preset frequency, if so, entering the next step; if the abnormal fluctuation frequency does not exceed the preset frequency, it can be determined that although smoke flows in the current environment, the current environment does not reach the judgment condition of fire, or other reasons such as smoke or oil smoke cause, the process returns to step S101, and the judgment is performed again after waiting for the next detection; and if the preset frequency is exceeded, entering the next step.

S106, judging that the smoke flow intensity of a preset monitoring space exceeds a fire alarm threshold value; generally, when the step is reached, it can be determined that the fire disaster occurs in the current environment, but considering that the step can be further added on the basis of the step in order to adapt to different scenes and crowds, which will be described in detail further below; the added steps can further reduce the false alarm rate, but the added judging steps delay the alarm time if the fire really occurs, and the alarm time can be set according to the actual requirements of users.

S110, judging that the fire disaster happens in the current environment.

The method combines the existing smoke sensation, when the smoke concentration detected by the original smoke sensation module exceeds the threshold value, the smoke condition is detected by the ultrasonic module again, and the final smoke alarm accuracy is higher and the occurrence of false alarm is reduced by combining the advantages of two smoke condition judgment methods in different modes.

In this embodiment, as shown in fig. 14, the step S104 specifically includes the following steps:

S1041, determining an effective peak value and a corresponding echo time point in ultrasonic data detected each time, wherein the effective peak value is a peak value exceeding a preset critical echo intensity value; the method comprises the following steps of screening out a normal peak and an abnormal peak, wherein the normal peak refers to a peak originally existing in a oscillogram and formed by object reflection; the abnormal peak refers to a peak caused by the influence of smoke, and as mentioned in embodiment 1, when the smoke concentration is high and the smoke is in a diffusion state, a wavelet peak sometimes appears in an area where the peak of the echo intensity value originally does not exist, and the frequency of the wavelet peak is faster and faster as the intensity of the smoke flow is higher; setting a preset critical echo intensity value, identifying abnormal wave peaks and normal wave peaks of which the wave peak values exceed the preset critical echo intensity value as effective wave peaks, and determining the effective wave peak values; the wavelet peak which does not exceed the preset critical echo intensity value is not considered because the wavelet peak cannot be determined to belong to normal fluctuation caused by the characteristics of ultrasonic waves or abnormal fluctuation generated due to the influence of smoke; after the processing of the step, only a plurality of echo time points and corresponding effective peak values are left in the ultrasonic data detected once.

s1042 integrates the ultrasonic data processed in the previous steps, determines the maximum effective peak value and the minimum effective peak value corresponding to each echo time point, and if the effective peak value appears only once at a certain echo time point, the minimum effective peak value is defaulted to be the preset critical echo intensity value; integrating the ultrasonic data which are detected in each round and processed in the step S1041 together, if an effective peak value only appears once at a certain echo time point, the maximum effective peak value corresponding to the echo time point is equal to the effective peak value, the minimum effective peak value is equal to a preset critical echo intensity value, and the situation usually appears at an abnormal peak; if a certain echo time point has multiple effective peak values, the maximum effective peak value and the minimum effective peak value corresponding to the echo time point are respectively the maximum value and the minimum value, and the situation usually occurs in a normal peak; the maximum effective peak value and the minimum effective peak value are determined, and the fluctuation amplitude of the echo intensity value corresponding to each echo time point in the current round of detection can be determined, which is also the purpose of the step.

S1043, determining the fluctuation ratio of the maximum effective peak value and the minimum effective peak value of each echo time point; the purpose of the step is to determine the fluctuation amplitude of the echo intensity value corresponding to each echo time point according to the fluctuation ratio of the maximum effective peak value to the minimum effective peak value, wherein the larger the fluctuation ratio is, the larger the fluctuation amplitude is.

S1044 determining that abnormal fluctuation exists at the echo time point with the fluctuation ratio being greater than the preset ratio; the purpose of the step is to screen out abnormal fluctuation and determine an echo time point with abnormal fluctuation amplitude; for a normal peak, if the fluctuation ratio is small, the fluctuation is indicated to belong to normal fluctuation caused by the characteristics of the ultrasonic waves, and if the fluctuation ratio is large, the fluctuation is indicated to belong to abnormal fluctuation caused by smoke influence; for the abnormal wave crest, the abnormal wave crest is caused by the influence of smoke which randomly appears, and the fluctuation ratio is always larger.

In addition to assisting in determining whether a fire occurs in the current environment through S103-S106, the determination may be further assisted through the following first method, which is specifically included in fig. 15:

S1071, judging whether the frequency of the abnormal fluctuation falls back after exceeding a preset frequency, if so, entering the next step; when smoke gradually diffuses to the whole environment, the whole smoke concentration of the environment rises and tends to be relatively stable, and then the oscillogram of the ultrasonic data develops towards two trends; firstly, the detected echo intensity value is obviously lower than that in the normal environment due to the existence of a large amount of smoke in the whole environment or the reflection or absorption of ultrasonic waves; secondly, the flow of smoke also causes fluctuations in the echo intensity values, but the amplitude of the fluctuations is no longer as great as the amplitude of the fluctuations when the detection is just started; this step is to determine the first trend condition.

S1072, judging whether the attenuation degree of the peak value of the normal peak in the ultrasonic data exceeds a threshold value, if so, entering the next step; if there is no attenuation or a low degree of attenuation, the smoke in the environment will gradually dissipate, possibly not a fire or a fire has been extinguished, only this will result in the abnormal fluctuation falling back while the peak value of the normal peak is not attenuated; of course, the average smoke concentration in the environment can be calculated approximately by calculating the attenuation of the peak-to-peak value of the normal peak.

S1073 judges that the predetermined monitored space has been completely filled with smoke.

Further, it can also assist in determining whether a fire occurs in the current environment by a second method, which specifically includes, with reference to fig. 16:

S1081, determining a reflection strong point and an echo time point corresponding to the reflection strong point according to a peak value of a normal peak in ultrasonic data; the reflection strong point refers to an object reflection point which can generate a peak value in a oscillogram in a preset background environment, the reflection strong point is objectively existed, the reflection strong point cannot be changed as long as the reflection strong point is unchanged in the preset background environment, but an echo time point corresponding to the reflection strong point can be changed due to the change of temperature-sound velocity.

S1082 compares the ultrasonic data of the most recent round detection with that of the first round detection.

s1083 screens and determines the same reflection intensity points in the two rounds of ultrasound data.

s1084, judging whether the variation of the echo time points corresponding to the same reflection strong points exceeds a threshold value, and if so, entering the next step; when a fire disaster occurs in the environment, the average temperature of the preset monitoring space gradually rises, the echo time points corresponding to the reflection strong points in the oscillogram reflecting the ultrasonic data gradually become smaller, the average temperature rise of the ultrasonic on the back-and-forth path can be roughly calculated by detecting the variation of the echo time points corresponding to the same reflection strong points, and then whether the fire disaster occurs or not is judged in an auxiliary manner.

S1085 determines that the temperature rise abnormality occurs in the predetermined monitored space.

Embodiment 3, referring to fig. 17, an ultrasound-based smoke flow intensity detection method, which is applicable to any device terminal or server that can acquire ultrasound data and perform processing calculation, includes:

S201, ultrasonic data detected by a preset number of times in a preset monitoring space is obtained, and the ultrasonic data comprises echo time and a corresponding echo intensity value.

S202, determining an effective peak value and a corresponding echo time point in the ultrasonic data detected each time, wherein the effective peak value is a peak value exceeding a preset critical echo intensity value.

S203 integrates the ultrasonic data, determines a maximum effective peak value and a minimum effective peak value corresponding to each echo time point, and if an effective peak value occurs only once at a certain echo time point, the minimum effective peak value is default to a preset critical echo intensity value.

S204, determining the fluctuation ratio of the maximum effective peak value to the minimum effective peak value of each echo time point.

S205 determines that there is an abnormal fluctuation at the echo time point where the fluctuation ratio is larger than the preset ratio.

S206 determines the intensity of the flow of smoke in the predetermined monitored space based on the frequency of the abnormal fluctuation.

The principle and technical effects of the method of this embodiment can be seen in example 1 and example 2.

Although the present invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and various changes in form and details may be made within the scope of the appended claims.

Claims

1. the utility model provides an alarm is felt to cigarette, includes the shell and establishes the inside circuit board of shell, the circuit board include microcontroller module and with module and alarm module are felt to cigarette that microcontroller module connects, its characterized in that: the circuit board further comprises an ultrasonic module connected with the microcontroller module, and when the smoke sensing module detects that the indoor smoke concentration exceeds a threshold value, the microcontroller module controls the ultrasonic module to start detecting a preset monitoring space and obtain ultrasonic data; and when the ultrasonic data exceeds a preset condition, the microcontroller module controls the alarm module to send an alarm signal.

2. a smoke detector alarm as claimed in claim 1 wherein: the ultrasonic module includes an ultrasonic transmission/reception probe fixedly attached to the through hole and oriented obliquely downward.

3. A smoke detector alarm as claimed in claim 2 wherein: the number of the through holes and the corresponding ultrasonic transceiving probes is 3.

4. A smoke detector alarm as claimed in claim 2 wherein: the ultrasonic module also comprises a fixed sleeve and a silica gel sleeve, and the ultrasonic transceiving probe is fixedly embedded into the silica gel sleeve; the silica gel sleeve is fixedly embedded into the fixed sleeve; the fixing sleeve is fixedly embedded into the through hole on the side surface of the shell.

5. A smoke detector alarm as claimed in claim 1 wherein: the device also comprises a mounting plate; the shell top surface is equipped with a plurality of cross-sections and is the protruding knot of "T" font, be equipped with on the mounting panel with protruding knot corresponds the complex through-hole, protruding knot passes behind the through-hole accessible rotation shell and makes shell and mounting panel fixed coordination.

6. a smoke detector alarm as claimed in claim 1 wherein: the circuit board further comprises an acceleration module connected with the microcontroller module, and the acceleration module is used for judging the motion condition of the smoke detector alarm by detecting the change of the acceleration; and when the change of the acceleration exceeds a threshold value, the microcontroller module controls the alarm module to send an alarm signal.

7. A smoke detector alarm as claimed in claim 1 wherein: the alarm module is a wireless communication alarm module or/and a sound and light alarm module; the microcontroller module can control the sound-light alarm module to send sound-light alarms to notify surrounding personnel, and the microcontroller module can control the wireless communication alarm module to send wireless alarm signals to notify a matched data platform.