CN220582644U - Filter screen reminding device suitable for air sterilizer and air sterilizer - Google Patents

Abstract

The utility model relates to a filter screen reminding device suitable for an air sterilizer, which comprises a frame, a filter screen, a fan assembly, a rotating speed acquisition circuit, a control unit and a prompting unit, wherein the characteristic that the actual rotating speed of a fan of the fan assembly is reduced due to blockage of the filter screen is utilized, the rotating speed acquisition circuit, the control unit and the prompting unit are arranged, the control unit acquires the actual rotating speed of the fan in real time through the rotating speed acquisition circuit, when the actual rotating speed of the fan is lower than a preset rotating speed range, the condition that the filter screen is blocked is indicated, and the control unit controls the prompting unit to prompt a user that the filter screen needs to be replaced in time. The fan rotating speed is not required to be detected by the permanent magnet, but the actual rotating speed of the fan is obtained by adopting a rotating speed acquisition circuit, the rotating speed of the fan cannot be influenced and disturbed, the inaccuracy of the measurement of the rotating speed of the fan caused by the disturbance is avoided, the problem of misjudgment on the result of whether the filter screen is replaced is solved, the actual requirement is met, and the use is convenient.

Description

Filter screen reminding device suitable for air sterilizer and air sterilizer

Technical Field

The utility model relates to the field of air disinfectors, in particular to a filter screen reminding device suitable for an air disinfector and the air disinfector.

Background

The air sterilizer is a machine for purifying and sterilizing air by the principles of filtering, purifying, sterilizing and the like. The air sterilizer mainly comprises a sterilizing module, a filter screen and a fan, wherein air inlet of an air inlet reaches the sterilizing module through the filter screen after the fan is started, and sterilizing factors released by the sterilizing module are taken out to an air outlet, so that the sterilizing factors can be diffused into air. However, as the use time increases, the filtering effect of the filter screen is gradually reduced, and the existing air purifier, air sterilizer and the like are provided with a filter screen monitoring function, so that a user can be reminded to protect the filter screen when the filter screen is blocked.

The existing publication number is CN207365221U is named as an air purifier with a filter screen replacement reminding function, a rotating speed detection mechanism is arranged in an air duct, the mechanism comprises a metal detection rod and two oppositely placed permanent magnets with opposite polarities, the permanent magnets are arranged on the inner wall of the air duct, the metal detection rod is positioned on one blade of a fan blade, the metal detection rod cuts a magnetic induction line between the two permanent magnets in the rotating process along with the fan to generate induction current, the current is larger than a current threshold value arranged in a controller, when the filter screen is blocked, air sucked by the fan cannot be effectively discharged, the pressure nearby the fan is increased, the damping of the fan is increased, the rotating speed of a motor is reduced under the damping action, the speed of the metal detection rod for cutting the magnetic induction line is reduced, at the moment, the induction current generated by the metal detection rod is reduced, when the controller detects that the induction current of the metal detection rod is smaller than the current threshold value, the service life of the filter screen is judged to be reached, and a warning lamp is controlled to flash, so that a user is reminded of replacing the filter screen.

However, in the prior art, the permanent magnet is arranged in the air duct to easily generate electromagnetic interference to the motor of the fan, the motor of the fan comprises a plurality of coils and magnetic fields, and the external strong magnetic field can interfere the normal operation of the motor, so that the output power of the motor is reduced, the motor performance is reduced, and the filter screen blockage condition is easily misjudged by using the means.

Disclosure of Invention

In view of the above problems, the utility model provides a filter screen reminding device suitable for an air sterilizer and the air sterilizer, which solve the problem that the existing permanent magnet easily generates electromagnetic interference to a motor of a fan, thereby forming erroneous judgment on the blocking condition of the filter screen.

In order to achieve the above object, in a first aspect, the present utility model provides a filter screen reminding device suitable for an air sterilizer, including a frame, a filter screen, a fan assembly, a rotation speed acquisition circuit, a control unit and a reminding unit, wherein a disinfection module is arranged on the frame; the filter screen is arranged on the frame and covers the input end of the disinfection module; the fan assembly is arranged on the frame and comprises a fan and a driving unit, and the driving unit is used for driving the fan to rotate; the rotating speed acquisition circuit is used for acquiring the rotating speed of the fan in real time; the control unit is electrically connected with the rotating speed acquisition circuit and is used for receiving the rotating speed of the fan acquired by the rotating speed acquisition circuit and sending a first control signal to the prompting unit when judging that the rotating speed of the fan exceeds a preset rotating speed range; the prompting unit is electrically connected with the control unit and is used for sending out prompting information after receiving the first control signal, and the prompting information is used for indicating to replace the filter screen.

In some embodiments, the system further comprises a humidity detection unit, wherein the humidity detection unit comprises a first humidity sensor, the first humidity sensor is arranged at the position of the disinfection module, and the first humidity sensor is electrically connected with the control unit and is used for detecting first humidity information of the current disinfection module; the control unit is also used for determining whether to send the first control signal to the prompting unit according to the comparison result of the first humidity information and the reference humidity information.

In some embodiments, the humidity detecting unit further includes a second humidity sensor disposed outside the frame, for detecting second humidity information of the external environment; the control unit is used for sending a first control signal to the prompt unit when the first humidity information is judged to be larger than the second humidity information.

In some embodiments, the device further comprises a detection control switch circuit, wherein the detection control switch circuit is electrically connected with the control unit and is used for controlling the humidity detection unit to be started according to a switch control signal transmitted by the control unit; the control unit is also used for sending a switch control signal to the detection control switch circuit when the fan rotating speed exceeds the preset rotating speed range.

In some embodiments, the number of screens is a plurality and the screens are arranged in an array on the frame in the direction of air flow.

In some embodiments, the rotation speed acquisition circuit includes a rising edge signal acquisition circuit and/or a falling edge signal acquisition circuit, a subtracter and a divider, where the rising edge signal acquisition circuit is electrically connected with the control unit and is used for acquiring two adjacent rising edge times in the square wave period of the driving unit; the falling edge signal acquisition circuit is electrically connected with the control unit and is used for acquiring two adjacent falling edge times of the driving unit in the square wave period; the subtracter is used for calculating the time difference of two adjacent rising edge times and/or the time difference of two adjacent falling edges; the divider is electrically connected with the subtracter and is used for calculating the ratio of the preset value to the time difference to obtain the rotating speed of the fan.

In some embodiments, the preset rotational speed range is 1500r/min to 2500r/min.

In some embodiments, the prompting unit is one of an audible alarm, a photoelectric alarm, and a vibrator.

In some embodiments, the control unit is an MCU processor.

In a second aspect, the utility model also provides an air sterilizer, which comprises a sterilizing module and a filter screen reminding device, wherein the filter screen reminding device is the filter screen reminding device in the first aspect.

In the above technical scheme, the characteristic that the blocking of the filter screen can lead to the actual rotating speed of the fan assembly to be reduced is utilized, a rotating speed acquisition circuit, a control unit and a prompting unit are arranged, the control unit acquires the actual rotating speed of the fan in real time through the rotating speed acquisition circuit, when the actual rotating speed of the fan is placed in a preset rotating speed range, the ventilation performance of the filter screen is good, when the actual rotating speed of the fan is lower than the preset rotating speed range, the filter screen is blocked, and the control unit controls the prompting unit to prompt a user that the filter screen needs to be replaced in time. In this technical scheme, need not adopt the permanent magnet to detect the fan rotational speed, but adopt the form of rotational speed acquisition circuit, realize the acquisition to the fan actual rotational speed, can not produce influence and interference to the rotational speed of fan, avoid producing the fan rotational speed because of the interference and measure inaccurately to whether change this result to the filter screen and produce the problem of misjudgement, more accord with actual demand, facilitate the use.

The foregoing summary is merely an overview of the present utility model, and may be implemented according to the text and the accompanying drawings in order to make it clear to a person skilled in the art that the present utility model may be implemented, and in order to make the above-mentioned objects and other objects, features and advantages of the present utility model more easily understood, the following description will be given with reference to the specific embodiments and the accompanying drawings of the present utility model.

Drawings

The drawings are only for purposes of illustrating the principles, implementations, applications, features, and effects of the present utility model and are not to be construed as limiting the utility model.

In the drawings of the specification:

FIG. 1 is a first schematic view of a filter screen reminding device according to an embodiment of the utility model;

FIG. 2 is a schematic diagram of a humidity detecting unit according to an embodiment of the present utility model;

FIG. 3 is a schematic view of an air sterilizer according to an embodiment of the present utility model;

FIG. 4 is a schematic diagram of a rotational speed acquisition circuit according to an embodiment of the present utility model;

fig. 5 is a second schematic diagram of a filter reminding device according to an embodiment of the utility model.

Reference numerals referred to in the above drawings are explained as follows:

1. a control unit;

2. a rotation speed acquisition circuit;

21. a rising edge signal acquisition circuit;

22. a falling edge signal acquisition circuit;

23. a subtracter;

24. a divider;

3. a humidity detection unit;

31. a first humidity sensor;

32. a second humidity sensor;

4. a frame;

5. a fan assembly;

51. a driving unit;

52. a fan;

6. a prompting unit;

7. a filter screen;

8. a killing module;

9. and detecting and controlling the switch circuit.

Detailed Description

In order to describe the possible application scenarios, technical principles, practical embodiments, and the like of the present utility model in detail, the following description is made with reference to the specific embodiments and the accompanying drawings. The embodiments described herein are only for more clearly illustrating the technical aspects of the present utility model, and thus are only exemplary and not intended to limit the scope of the present utility model.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the utility model. The appearances of the phrase "in various places in the specification are not necessarily all referring to the same embodiment, nor are they particularly limited to independence or relevance from other embodiments. In principle, in the present utility model, as long as there is no technical contradiction or conflict, the technical features mentioned in each embodiment may be combined in any manner to form a corresponding implementable technical solution.

Unless defined otherwise, technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present utility model pertains; the use of related terms herein is for the purpose of describing particular embodiments only and is not intended to limit the utility model.

In the description of the present utility model, the term "and/or" is a representation for describing a logical relationship between objects, which means that three relationships may exist, for example a and/or B, representing: there are three cases, a, B, and both a and B. In addition, the character "/" herein generally indicates that the front-to-back associated object is an "or" logical relationship.

In the present utility model, terms such as "first" and "second" are used merely to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual number, order, or sequence of such entities or operations.

Without further limitation, the use of the terms "comprising," "including," "having," or other like open-ended terms in this application are intended to cover a non-exclusive inclusion, such that a process, method, or article of manufacture that comprises a list of elements does not include additional elements in the process, method, or article of manufacture, but may include other elements not expressly listed or inherent to such process, method, or article of manufacture.

As in the understanding of "review guidelines," the expressions "greater than", "less than", "exceeding" and the like are understood to exclude this number in the present utility model; the expressions "above", "below", "within" and the like are understood to include this number. Furthermore, in the description of embodiments of the present utility model, the meaning of "a plurality of" is two or more (including two), and similarly, the expression "a plurality of" is also to be understood as such, for example, "a plurality of" and the like, unless specifically defined otherwise.

In the description of embodiments of the present utility model, spatially relative terms such as "center," "longitudinal," "transverse," "length," "width," "thickness," "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counter-clockwise," "axial," "radial," "circumferential," etc., are used herein as a basis for the description of the embodiments or as a basis for the description of the embodiments, and are not intended to indicate or imply that the devices or components referred to must have a particular position, a particular orientation, or be configured or operated in a particular orientation and therefore should not be construed as limiting the embodiments of the present utility model.

Unless specifically stated or limited otherwise, the terms "mounted," "connected," "affixed," "disposed," and the like as used in the description of embodiments of the utility model should be construed broadly. For example, the "connection" may be a fixed connection, a detachable connection, or an integral arrangement; the device can be mechanically connected, electrically connected and communicated; it can be directly connected or indirectly connected through an intermediate medium; which may be a communication between two elements or an interaction between two elements. The specific meaning of the above terms in the embodiments of the present utility model can be understood by those skilled in the art to which the present utility model pertains according to circumstances.

Referring to fig. 1, in a first aspect, the present embodiment provides a filter screen 7 reminding device suitable for an air sterilizer, including a frame 4, a filter screen 7, a fan 52 assembly 5, a rotation speed acquisition circuit 2, a control unit 1 and a reminding unit 6, wherein a disinfection module 8 is disposed on the frame 4; the filter screen 7 is arranged on the frame 4 and covers the input end of the sterilizing module 8; the fan 52 assembly 5 is arranged on the frame 4 and comprises a fan 52 and a driving unit 51, wherein the driving unit 51 is used for driving the fan 52 to rotate; the rotation speed acquisition circuit 2 is used for acquiring the rotation speed of the fan 52 in real time; the control unit 1 is electrically connected with the rotating speed acquisition circuit 2, and is used for receiving the rotating speed of the fan 52 acquired by the rotating speed acquisition circuit 2 and sending a first control signal to the prompt unit 6 when the rotating speed of the fan 52 is judged to exceed a preset rotating speed range; the prompting unit 6 is electrically connected with the control unit 1 and is used for sending out prompting information after receiving the first control signal, wherein the prompting information is used for indicating the replacement of the filter screen 7.

In this embodiment, the frame 4 may be an outer housing of an air sterilizer; the rotation speed acquisition circuit 2, the control unit 1 and the prompt unit 6 are all electric elements. The filter screen 7, the sterilizing module 8 and the fan 52 can be referred to the arrangement scheme shown in fig. 3: along the circulation direction of air sets gradually, in the air inlet of suction frame 4 when air is rotated by fan 52, through filter screen 7 carry out preliminary filtration to the dust in the air after get into and disinfect module 8, disinfect the interior circular telegram of module 8 and produce the factor of disinfecting, disinfect the bacterium or the virus in the air, and the air after the purification is circulated to outside through the air outlet of fan 52 again. Notably, the kill factor of the kill module 8 depends on the kill form of the kill module 8: if the ultraviolet lamp is used for sterilization, the sterilization factor is ultraviolet light wave, if the ozone is used for sterilization, the sterilization factor is ozone molecule, and the sterilization module 8 and the sterilization factor are not specifically limited in this embodiment.

In this embodiment, during the continuous use of the air sterilizer, dust in the air may accumulate on the filter screen 7, block the ventilation holes on the filter screen 7, and further affect the flow rate of the air entering the air inlet of the frame 4, so that the fan 52 cannot smoothly suck the air, and the actual rotation speed of the fan 52 is lower than the rated rotation speed. By utilizing this principle, the present embodiment determines the actual rotation speed of the fan 52 by acquiring the actual rotation speed, thereby obtaining the actual working state of the fan 52, and further determining whether the filter screen 7 needs to be replaced.

In this embodiment, the rotational speed acquisition circuit 2 is additionally configured to acquire an actual rotational speed of the fan 52 and send the actual rotational speed to the control unit 1, and the control unit 1 determines whether the fan 52 is in a normal running state according to determining whether the rotational speed of the fan 52 exceeds a preset rotational speed range, and it should be noted that whether the rotational speed of the fan 52 exceeds the preset rotational speed range specifically includes: when the actual rotation speed is smaller than the preset rotation speed range, the actual rotation speed of the fan 52 is reduced, and the filter screen 7 is blocked. The preset rotational speed range may be a rated rotational speed of the fan 52, a rated output power of the driving motor, or a rotational speed value manually set. Alternatively, the preset rotational speed range may include a plurality of rotational speed values, for example: the fan 52 is provided with a plurality of rotational speed gears, and the preset rotational speed range corresponds to the rated rotational speed corresponding to each rotational speed gear of the fan 52. The control unit 1 is also used for controlling the prompt unit 6 to send out prompt information and timely reminding a user to replace the filter screen 7.

The technical scheme in this embodiment does not need to adopt the permanent magnet to detect the rotation speed of the fan 52, but adopts the form of the rotation speed acquisition circuit 2, so as to realize the acquisition of the actual rotation speed of the fan 52, and the rotation speed of the fan 52 cannot be influenced and disturbed, so that the inaccuracy in the measurement of the rotation speed of the fan 52 caused by the disturbance is avoided, the problem of misjudgment on the result of whether the filter screen 7 is replaced is solved, the actual requirement is met, and the use is convenient.

Referring to fig. 1, in some embodiments, the system further includes a humidity detection unit 3, where the humidity detection unit 3 includes a first humidity sensor 31, the first humidity sensor 31 is disposed at the position of the disinfection module 8, and the first humidity sensor 31 is electrically connected to the control unit 1 and is used for detecting first humidity information of the current disinfection module 8; the control unit 1 is further configured to determine whether to send the first control signal to the prompting unit 6 according to a comparison result of the first humidity information and the reference humidity information.

It should be noted that when the filter screen 7 is blocked, the air flow rate between the fan 52 and the sterilizing module 8 is slow, and the air humidity is greater than the external environment humidity, where the air humidity refers to the relative humidity, that is, the humidity at the current stage of the sterilizing module 8 is different from the humidity at the normal flow rate. At normal flow rates, the humidity at the disinfection module 8 is consistent with the humidity of the external environment. By using this principle, the humidity detection unit 3 is added in this embodiment to confirm the change of the air flow rate: when the filter screen 7 is blocked, not only the actual rotation speed of the fan 52 is reduced, but also the humidity value at the sterilizing module 8 is larger than the external environment humidity.

The first humidity sensor 31 is disposed at the location of the sterilizing module 8, specifically, the first humidity sensor 31 is disposed toward the sterilizing module 8 and inside the frame 4. The reference humidity information can be set manually, the air humidity value in the current application scene can be obtained from the internet in real time through a networking mode, and the reference humidity information can also be obtained through actual detection, and the embodiment is not limited in this way.

After the control unit 1 acquires the first humidity information, it is determined whether the first humidity information is greater than the reference humidity information, and if so, a first control signal is sent to the prompting unit 6.

This method can be used together with the principle of determining the actual rotation speed of the fan 52, and can be used as a secondary confirmation of the clogging state of the filter screen 7, so as to avoid erroneous determination of the clogging state of the filter screen 7 by the control unit 1 caused by the reduction of the rotation speed of the fan 52 due to an external factor.

Referring to fig. 2, in some embodiments, the humidity detecting unit 3 further includes a second humidity sensor 32 disposed outside the frame 4 for detecting second humidity information of the external environment; the reference humidity information is second humidity information, and the control unit 1 is configured to send a first control signal to the prompting unit 6 when determining that the first humidity information is greater than the second humidity information. The second humidity sensor 32 can detect the second humidity information of the external environment and update the second humidity information to the reference humidity information, which can make the humidity detection information more accurate.

Referring to fig. 2, in some embodiments, the apparatus further includes a detection control switch circuit 9, where the detection control switch circuit 9 is electrically connected to the control unit 1, and is configured to control the humidity detection unit 3 to be turned on according to a switch control signal transmitted by the control unit 1; the control unit 1 is further configured to send a switch control signal to the detection control switch circuit 9 when it is determined that the rotational speed of the fan 52 exceeds the preset rotational speed range.

The detection control switch circuit 9 is used to control the on/off of the humidity detection unit 3, and fig. 2 shows a preferred embodiment: when the control unit 1 obtains that the actual rotation speed of the current fan 52 exceeds the preset rotation speed range, the detection control switch circuit 9 is controlled to start the humidity detection unit 3, the ambient humidity and the humidity at the sterilizing module 8 are detected, the actual first humidity information and the actual second humidity information are obtained, and the blocking state of the current filter screen 7 is judged according to the first humidity information and the second humidity information.

Through setting up detection control switch circuit 9, can selectively turn on humidity detection unit 3, reduce the power consumption of humidity detection unit 3, also can save the live time of humidity detection unit 3 simultaneously, extension humidity detection unit 3's life.

Referring to fig. 3, in some embodiments, a plurality of filter screens 7 are arranged on the frame 4 in an array along the air flowing direction. The filtration dust capacity of the single-layer filter screen 7 is limited, and particularly when the single-layer filter screen 7 is replaced, air dust in a gap is replaced to enter the frame 4, and the multi-layer filter screen 7 is additionally arranged, so that the air dust can be further filtered, and the dust is prevented from entering the frame 4 in the replacement process of the filter screen 7 to affect the service life of the disinfection module 8.

In some preferred embodiments, the multi-layer filter 7 is made of different materials, and performs multi-directional filtration on air: for example, the first filter 7 is mainly used for filtering PM2.5 particles, the second filter 7 is mainly used for filtering PM1.2 particles, and so on, and the air purifying capacity can be improved under the arrangement of the multiple layers of filter 7.

Referring to fig. 4, in some embodiments, the rotation speed acquisition circuit 2 includes a rising edge signal acquisition circuit 21 and/or a falling edge signal acquisition circuit 22, a subtracter 23, and a divider 24, where the rising edge signal acquisition circuit 21 is electrically connected to the control unit 1, and is configured to acquire two adjacent rising edge times in a square wave period of the driving unit 51; the falling edge signal acquisition circuit 22 is electrically connected with the control unit 1 and is used for acquiring two adjacent falling edge times of the driving unit 51 in the square wave period; the subtracter 23 is used for calculating the time difference of two adjacent rising edge times and/or the time difference of two adjacent falling edges; the divider 24 is electrically connected to the subtractor 23, and is configured to calculate a ratio of the preset value to the time difference, so as to obtain the rotation speed of the fan 52.

In the square wave period, the driving unit 51 has a plurality of rising edges and falling edges that are adjacently disposed, and may be selected according to a time period corresponding to the rising edge signal or a time period corresponding to the falling edge signal. The actual rotation speed of the fan 52 is obtained by calculation of the subtracter 23 and the divider 24.

The above process can be understood specifically in connection with the following practical examples:

the control unit 1 collects pulse waveforms of the fan 52 motor and analyzes the collected pulse waveforms;

achieving the fan 52 rotational speed by resolution requires measuring the square wave period T1+ T2, where T1 and T2 are the time difference between two adjacent rising edges (or falling edges). In practical application, the method can be realized through an input capturing mode and a DMA function of a TIM peripheral in STM32, and the specific process is as follows:

1. the TIM peripheral is set to input capture mode, the prescaler PSC is set to 720-1, the auto loader ARR is set to 65535, the count mode is selected to count up, and the capture mode is selected to be falling edge triggered.

2. And starting the DMA channel, and transmitting the captured count value to a memory for subsequent calculation and analysis.

3. When the DMA is full, the time difference is obtained by calculating the two captured falling edges in the memory (as in the above t1+t2 calculation formula).

4. The rotational speed is calculated according to the formula n=30 (seconds)/(t1+t2), and the rotational speed of the fan 52 is obtained and stored in the array.

5. And carrying out equalization filtering treatment on the stored fan 52 rotating speed array, wherein the obtained fan 52 rotating speed can be more fit with an actual value.

In some embodiments, the preset rotational speed range is 1500r/min to 2500r/min. Preferably 2000r/min.

In some embodiments, the prompting unit 6 is one of an audible alarm, a photoelectric alarm, and a vibrator. The audible alarm can be a buzzer or a voice broadcasting module, and the user is timely reminded of replacing the filter screen 7 in an audible prompt mode. Alternatively, in some environments where silence is desired, the prompting unit 6 may also be a vibrator or a photoelectric alarm, which may be an indicator light.

In some embodiments, the control unit 1 is an MCU processor.

In a second aspect, the embodiment further provides an air sterilizer, which comprises a sterilizing module 8 and a filter screen 7 reminding device, wherein the filter screen 7 reminding device is the filter screen 7 reminding device in the first aspect.

Referring to fig. 5, in order to apply the above technical solution to a specific embodiment in a practical scenario, the control unit 1 is an MCU processor, and it is noted that an STM32 module is disposed in the MCU processor; the indication unit is a signal lamp and/or a buzzer, and the driving unit 51 is a fan 52 motor.

The actual rotation speed of the fan 52 is obtained through the rotation speed acquisition circuit 2, the principle of the specific rotation speed acquisition circuit 2 can be understood by referring to the foregoing, the MCU judges whether the rotation speed value of the fan 52 is smaller than the preset rotation speed range, if yes, the MCU (STM 32) is triggered to acquire the detection information of the first humidity sensor 31 and the second humidity sensor 32, and if the humidity value detected by the second humidity sensor 32 is larger than the humidity value detected by the first humidity sensor 31, the surrounding humidity of the disinfection module 8 is larger than the external surrounding environment humidity; triggering a buzzer to sound and/or a signal lamp to flash, so as to remind a user to replace the filter screen 7.

In the above technical scheme, by utilizing the characteristic that the blockage of the filter screen 7 can lead to the slowing of the actual rotation speed of the fan 52 assembly 5, the rotation speed acquisition circuit 2, the control unit 1 and the prompting unit 6 are arranged, the control unit 1 acquires the actual rotation speed of the fan 52 in real time through the rotation speed acquisition circuit 2, when the actual rotation speed of the fan 52 is placed in a preset rotation speed range, the ventilation performance of the filter screen 7 is good, when the actual rotation speed of the fan 52 is lower than the preset rotation speed range, the filter screen 7 is blocked, and the control unit 1 controls the prompting unit 6 to prompt a user that the filter screen 7 needs to be replaced in time. In this technical scheme, need not adopt the permanent magnet to detect the fan 52 rotational speed, but adopt the form of rotational speed acquisition circuit 2, realize the acquisition to the actual rotational speed of fan 52, can not produce influence and interference to the rotational speed of fan 52, avoid producing because of the interference that the measurement of fan 52 rotational speed is inaccurate to whether change this result to filter screen 7 produces the problem of misjudgement, more accord with actual demand, facilitate the use.

Finally, it should be noted that, although the embodiments have been described in the text and the drawings, the scope of the utility model is not limited thereby. The technical scheme generated by replacing or modifying the equivalent structure or equivalent flow by utilizing the content recorded in the text and the drawings of the specification based on the essential idea of the utility model, and the technical scheme of the embodiment directly or indirectly implemented in other related technical fields are included in the patent protection scope of the utility model.

Claims (10)

1. A screen reminder device for an air sterilizer, comprising:

the frame is provided with a killing module;

the filter screen is arranged on the frame and covers the input end of the disinfection module;

the fan assembly is arranged on the frame and comprises a fan and a driving unit, and the driving unit is used for driving the fan to rotate;

the rotating speed acquisition circuit is used for acquiring the rotating speed of the fan in real time;

the control unit is electrically connected with the rotating speed acquisition circuit and is used for receiving the rotating speed of the fan acquired by the rotating speed acquisition circuit and sending a first control signal to the prompting unit when the rotating speed of the fan is judged to exceed a preset rotating speed range;

the prompting unit is electrically connected with the control unit and is used for sending out prompting information after receiving the first control signal, and the prompting information is used for indicating the replacement of the filter screen.

2. The screen reminder device for an air sterilizer of claim 1, further comprising:

the humidity detection unit comprises a first humidity sensor, wherein the first humidity sensor is arranged at the position of the disinfection module, and is electrically connected with the control unit and used for detecting first humidity information of the current disinfection module;

the control unit is further configured to determine whether to send a first control signal to the prompting unit according to a comparison result of the first humidity information and the reference humidity information.

3. The screen reminder device for an air sterilizer of claim 2, wherein the humidity detection unit further comprises:

the second humidity sensor is arranged on the outer side of the frame and is used for detecting second humidity information of the external environment;

the reference humidity information is the second humidity information, and the control unit is used for sending a first control signal to the prompt unit when the first humidity information is determined to be larger than the second humidity information.

4. The screen reminder device for an air sterilizer of claim 2, further comprising:

the detection control switch circuit is electrically connected with the control unit and is used for controlling the humidity detection unit to be started according to a switch control signal transmitted by the control unit;

the control unit is also used for sending the switch control signal to the detection control switch circuit when the fan rotating speed is judged to exceed the preset rotating speed range.

5. The screen reminding device for an air sterilizer according to claim 1, wherein the number of screens is plural, and the screens are arranged on the frame in an array along a flow direction of the air.

6. The screen reminder device for an air sterilizer of claim 1, wherein the rotational speed acquisition circuit comprises:

the rising edge signal acquisition circuit is electrically connected with the control unit and is used for acquiring two adjacent rising edge times in the square wave period of the driving unit;

and/or a falling edge signal acquisition circuit, which is electrically connected with the control unit and is used for acquiring two adjacent falling edge time of the driving unit in the square wave period;

the subtracter is used for calculating the time difference of the two adjacent rising edge times and/or the time difference of the two adjacent falling edges;

and the divider is electrically connected with the subtracter and is used for calculating the ratio of the preset value to the time difference to obtain the rotating speed of the fan.

7. The screen reminder device for an air sterilizer of claim 1, wherein the preset rotational speed range is 1500r/min-2500r/min.

8. The screen reminding device for an air sterilizer according to claim 1, wherein the reminding unit is one of an audible alarm, a photoelectric alarm and a vibrator.

9. The screen reminder device for an air sterilizer of claim 1, wherein the control unit is an MCU processor.

10. An air sterilizer, comprising:

a killing module;

a screen reminder as claimed in any one of claims 1 to 9.