JP6782395B2 - Air cleaner - Google Patents

Description

The present invention relates to an air purifier.

Conventionally, the main body case has an air purifying part such as a filter and a blowing part such as a fan motor, and by driving the blowing part, the air purifying part sucks air dust and the like from the suction port. Air purifiers that remove (collect) are known (see, for example, Patent Documents 1 and 2).

The air purifiers of Patent Documents 1 and 2 are provided with a dirt detection unit (dust detector in Patent Document 2) that detects fine particles such as dust contained in the air, and the blower unit is based on the detection result of the dirt detection unit. It is designed to control the drive.

Such a dirt detection unit of an air purifier includes a light emitting element that emits light, a light receiving element that receives light, and a heating unit. The dirt detection unit carries fine particles such as dust into the detection region of the light emitting element and the light receiving element by the updraft generated by the heating unit, irradiates the light of the light emitting element into the detection region, and emits light from the fine particles existing in the detection region. The presence or absence of fine particles can be detected by receiving the reflected light with the light receiving element. Then, the received signal is amplified so that it can be easily handled by a control unit such as a microcomputer.

Japanese Unexamined Patent Publication No. 2015-64173 JP-A-2002-89907

By the way, in the dirt detection unit of the air purifier as described above, fine particles such as dust are carried into the detection area by the updraft generated by heating the heat source, and the fine particles carried in the detection area are detected. There is.

However, it is not possible to carry relatively large fine particles such as pollen into the detection area only by heating the heat source, or it is difficult to maintain high detection accuracy for a long time for the fine particles to stay in the detection area.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an air purifier capable of improving the detection accuracy of fine particles in a dirt detecting unit.

In order to solve the above problems, the air purifier is provided in the main body case having a suction port and an outlet, a blower portion that sucks air from the suction port and blows it out from the outlet, and the main body case. An air purifying unit that purifies the air that has flowed in from the suction port, and a dirt detecting unit that detects fine particles contained in the air that has flowed in from the suction port in the detection region and outputs an output signal according to the particle size of the fine particles. An air purifier having a control unit that determines dirt based on the output signal of the dirt detection unit, an updraft generating means that guides the air in the detection area with an updraft, and the detection area. In addition, a downdraft generating means for guiding the air with a downdraft and an airflow control for controlling the updraft generating means and the downdraft generating means so that the downdraft and the updraft are alternately guided to the detection region. The control unit includes a device , has a threshold value corresponding to a predetermined particle size, and uses the output signal in the updraft, the output signal in the downdraft, and the threshold output from the dirt detection unit . With respect to the fine particles contained in the air, another particle size larger than the predetermined particle size is determined .

According to the air purifier of the present invention, it is possible to improve the detection accuracy of fine particles in the dirt detection unit.

It is a perspective view of the air purifier in an embodiment. It is sectional drawing of the air purifier in the same as above. It is the schematic block diagram of the dust sensor of the air purifier in the same as above. It is a block diagram which shows the electric structure of the air purifier in the same as above. It is a schematic block diagram for demonstrating the arrangement mode of the dust sensor of the air purifier in the same above. (A) to (c) are sectional views of the air purifier for explaining the operation mode of the air purifier in the same as above. It is a graph for demonstrating the signal strength and the particle diameter of the dust sensor at the time of downdraft generation. It is a graph for demonstrating the signal strength and the particle diameter of the dust sensor at the time of the updraft generation. It is a schematic block diagram which shows another example of the updraft generation means and the downdraft generation means.

Hereinafter, an embodiment of the air purifier will be described with reference to the drawings.

As shown in FIG. 1, the air purifier of the present embodiment has a substantially box-shaped main body case 1, and a suction port 2 is provided on the front side of the main body case 1. Further, an outlet 3 is provided on the upper surface (top surface) side of the main body case 1.

As shown in FIGS. 1 and 2, a filter 4 as an air purifying portion is detachably provided at the suction port 2. The filter 4 has two types of filters 4a and 4b. The filter 4a acts as a dust collecting filter for collecting, for example, dust and so-called PM2.5, and the filter 4b acts as a deodorizing filter for removing odors. In the main body case 1, a fan motor 5 as a blower for blowing out the air flowing in from the suction port 2 from the blowout port 3 is housed.

Further, a front panel 6 is provided on the front side of the filter 4 so as to cover the filter 4.

The front panel 6 can be moved in the front-rear direction as a whole by the panel actuator 6a (see FIG. 4), or only the lower end portion can be moved in the front-rear direction.

Further, a louver 7 is provided at the outlet 3 so as to be tiltable, and the tilting operation is performed by the louver actuator 7a (see FIG. 4).

As shown in FIGS. 1 and 2, a dust sensor 8 as a dirt detection unit is provided in the main body case 1.

More specifically, as shown in FIG. 5, the dust sensor 8 is provided in a flow path (air passage) R2 different from the flow path R1 in which the filter 4 is provided. The flow path R2 provided with the dust sensor 8 merges with the flow path R1 provided with the filter 4 on the downstream side. Then, the fan motor 5 is housed in the merging flow path R3 where the flow path R2 provided with the dust sensor 8 and the flow path R1 provided with the filter 4 merge. That is, since the flow path R2 provided with the dust sensor 8 communicates with the merging flow path R3, when the fan motor 5 operates, the air sucked from the suction port 2 is transferred from the flow paths R1 and R2 to the merging flow path R3. It is designed to be inhaled.

As shown in FIGS. 3 and 4, the dust sensor 8 has an airflow control fan 10 and a detection unit 11 in the sensor housing 9.

As shown in FIG. 3, the sensor housing 9 is hollow and houses a linear flow path forming portion 12 and two detecting portions accommodating the detection portions 11 on both sides from the longitudinal intermediate portion of the flow path forming portion 12. Parts 13 and 14 are extended.

An opening 12a through which air can flow in is mainly formed at the base end portion (lower in FIG. 3) of the flow path forming portion 12, and mainly at the tip end portion (upper side in FIG. 3) of the flow path forming portion 12. An opening 12b is formed that allows air to flow out.

Inside the flow path forming portion 12, the airflow control fan 10 is supported by a support portion (not shown) near the base end portion.

The airflow control fan 10 is a fan that can rotate in the forward and reverse directions, and provides an updraft Au having a strength that allows fine particles (for example, relatively small fine particles such as PM2.5) to pass through the detection region Ar described later during forward rotation. It can be generated in the flow path forming portion 12, and at the time of reversal, a downdraft Ad having the same degree as the updraft Au can be generated in the flow path forming portion 12.

Further, the two detection unit accommodating portions 13 and 14 are formed so as to form a three-pronged shape centering on the flow path forming portion 12. That is, one detection unit accommodating unit 13 and the other detection unit accommodating unit 14 are provided so as to be located on opposite sides of the flow path forming unit 12.

The light receiving element 15 constituting the detection unit 11 is housed in one detection unit accommodating unit 13, and the light emitting element 16 constituting the detection unit 11 is housed in the other detection unit accommodating unit 14.

As shown in FIG. 4, the detection unit 11 includes a light emitting element 16 that irradiates light, a light receiving element 15 that receives light and outputs a current signal corresponding to the amount of light, and a current signal output from the light receiving element 15. It has a signal conversion unit 17 that converts and outputs a pulse signal corresponding to the amount of fine particles.

As the light emitting element 16, for example, a light emitting LED or a semiconductor laser that outputs light in one direction based on the supply of power can be used. Further, as the light receiving element 15, for example, a photodiode whose output current changes according to the amount of light received can be used.

By arranging the condensing lenses 15a and 16a in the light irradiation direction of the light emitting element 16 and the light receiving direction of the light receiving element 15 to collect light, the amount of light in the detection region Ar can be increased and finer fine particles can be detected. I have to. Since the condenser lenses 15a and 16a increase the amount of light, they can be omitted if the target detection specifications can be satisfied even if they are not arranged.

As shown in FIG. 4, the signal conversion unit 17 includes an amplifier circuit 18, a comparison circuit 19, and an output circuit 20.

The amplifier circuit 18 amplifies the signal output from the light receiving element 15 and outputs the signal to the comparison circuit 19. As shown in FIGS. 7 and 8, the comparison circuit 19 is pulsed by comparing the signal output from the amplifier circuit 18 with the threshold values VA and VB (see FIGS. 7 and 8) which are the determination reference values. The signal is output to the output circuit 20 as a comparison result. In the following, the comparison result compared with the threshold value VA is treated as the output A, and the comparison result compared with the threshold value VB is treated as the output B.

The output circuit 20 appropriately converts the pulsed signal output from the comparison circuit 19 into a voltage level that can be easily handled by the control unit 21, which will be described later, and outputs the converted signal to the control unit 21. The airflow control fan 10 (see FIG. 3) alternately performs a forward rotation operation and a reverse rotation operation based on the control signal output from the control unit 21 when the dust sensor 8 (see FIG. 3) detects fine particles. It has become like.

Then, as shown in FIG. 3, during the normal rotation operation, the air sucked from the opening 12a into the flow path forming portion 12 has a strength that allows fine particles (for example, relatively small fine particles such as PM2.5) to pass through. An updraft Au is generated toward the detection region Ar. Further, during the reverse operation, a downdraft Ad that causes the air sucked from the opening 12b to descend toward the detection region Ar is generated.

As shown in FIG. 4, the control unit 21 is electrically connected to the fan motor 5, the dust sensor 8, and the actuators 6a and 7a, and controls each unit to control the air purifier in an integrated manner. Is. By controlling each unit, the control unit 21 controls the air purifier in three patterns of "smoke / smoke" operation, "house dust" operation, and "pollen" operation.

As shown in FIG. 6A, in the “odor / smoke” operation, for example, when the dust sensor 8 detects fine particles of less than 2 μm, the entire front panel 6 is moved forward and the louver 7 is moved to the main body case 1. Purified air is ejected in a state of facing upward so as to be approximately 90 degrees. By such an operation, the air in the entire room is sequentially taken in from the suction port 2, and the odor and smoke are mainly removed by the filter 4a.

As shown in FIG. 6B, in the "house dust" operation, for example, when the dust sensor 8 detects fine particles of 2 μm or more and less than 5 μm, only the lower part of the front panel 6 is moved forward to move the front panel 6 forward. While tilting, purified air is ejected with the louver 7 at approximately 45 degrees with respect to the main body case 1. By such an operation, the air that stays in the room from the middle part to the lower part in the height direction is sequentially taken in from the suction port 2, and the house dust that tends to stay in the area is mainly removed by the filter 4a.

As shown in FIG. 6 (c), in the "pollen" operation, for example, when the dust sensor 8 detects fine particles of 5 μm or more, only the lower part of the front panel 6 is moved forward to tilt the front panel 6 and the front panel 6 is tilted. The fan motor 5 is driven in a state where the louver 7 is approximately 30 degrees with respect to the main body case 1. By such an operation, the air that stays in the vicinity of the floor in the room is sequentially taken in from the suction port 2, and the pollen that tends to stay in the region is mainly removed by the filter 4a.

Next, changes in the detection signals when the updraft Au and the downdraft Ad are generated in the flow path forming portion 12 by the airflow control fan 10 will be described with reference to FIGS. 7 and 8.

In FIGS. 7 and 8, the threshold value VA is a threshold value for determining whether or not the detection signals S1 to S4 output from the light receiving element 15 via the amplifier circuit 18 are signals that detect fine particles exceeding 1 μm. The threshold value VB is a threshold value for determining whether or not the detection signals S1 to S4 output from the light receiving element 15 via the amplifier circuit 18 are signals that detect fine particles exceeding 2 μm.

The detection signal S1 indicates the signal intensity (receiver signal) when fine particles of 1 μm or more and less than 2 μm are detected, and in this case, the output A is output as the pulse output output from the comparison circuit 19.

The detection signal S2 indicates the signal strength when fine particles exceeding 2 μm are detected. In this case, the output A and the output B are output as the pulse outputs output from the comparison circuit 19.

The detection signals S3 and S4 indicate the signal strength when fine particles exceeding 5 μm or 10 μm are detected, and the output A and the output B are output as pulse outputs.

FIG. 8 shows the signal strength (receiver signal) of the light receiving element 15 and the waveform of the pulse output output to the control unit 21 when the updraft Au is generated by the airflow control fan 10. In the weak updraft Au by the airflow control fan 10, fine particles exceeding 5 μm and 10 μm do not reach the detection region Ar, so outputs A and B that detect fine particles up to 2 μm are output to the control unit 21 and exceed 5 μm. The output A and the output B in which the fine particles are detected are not output to the control unit 21.

FIG. 7 shows the signal strength of the light receiving element 15 and the waveform of the pulse output output to the control unit 21 when the downdraft Ad is generated by the airflow control fan 10. In the downdraft Ad, in addition to the fine particles exceeding 1 μm and 2 μm, the fine particles exceeding 5 μm or 10 μm stably pass through the detection region Ar. Therefore, the pulse output shown in FIG. 7 is obtained.

The control unit 21 alternately generates an updraft Au and a downdraft Ad in the flow path forming unit 12 of the dust sensor 8 during the fine particle detection operation, and compares the detected outputs A and B from 1 μm. It is possible to detect fine particles having a particle size in the range exceeding 10 μm.

In this embodiment, as shown in FIG. 8, even if fine particles exceeding 5 μm and 10 μm cannot be detected when the updraft Au is generated, 1 μm to 10 μm is set as shown in FIG. 7 when the downdraft Ad is generated. It is possible to detect even fine particles that exceed. Therefore, the presence of fine particles exceeding 1 μm to 10 μm can be detected in the air. More specifically, it is as follows. When the output A and the output B are turned on during the detection operation during the downdraft Ad generation and the output A and the output B are off during the detection operation during the updraft Au generation, the control unit 21 has a particle size of 5 μm or 10 μm. It can be determined that the above is the case.

Next, the operation (one operation example) of the air purifier formed as described above will be described.

In the air purifier of the present embodiment, the operation unit is operated by the user, and the control unit 21 controls the airflow control fan 10 based on the operation to determine the air pollution in the room.

That is, the airflow control fan 10 is controlled to repeat the forward rotation operation and the reverse rotation operation for a predetermined time. Then, by comparing the pulse output during the forward rotation operation and the pulse output during the reverse rotation operation, it is detected whether or not fine particles in the range of 1 μm to more than 10 μm are present.

Then, based on the difference in the particle size of the detected fine particles, the air cleaning operation is performed by any of the "odor / smoke" operation, the "house dust" operation, and the "pollen" operation.

In addition, the period length of the predetermined time for repeating the forward rotation operation and the reverse rotation operation by the airflow control fan 10 during each operation of "smoke / smoke" operation, "house dust" operation, and "pollen" operation is "smoke / smoke". The operation is performed so that the operation becomes longer in the order of operation <"house dust" operation <"pollen" operation. That is, based on the detected particle diameter, the operation is performed so that the larger the particle diameter size, the longer the period of the predetermined time. The reason is that the larger the particle size of the fine particles, the more difficult it is to be sucked into the suction port 2 shown in FIGS. 1 and 2. Therefore, the larger the particle size of the fine particles, the longer it takes to be sucked into the suction port 2.

With the above-mentioned air purifier, the following effects can be obtained.

(1) By alternately generating updraft Au and downdraft Ad in the flow path forming portion 12 and detecting fine particles on the detection region Ar, fine particles in the range of 1 μm to more than 10 μm can be detected. ..

(2) By alternately generating updraft Au and downdraft Ad in the flow path forming portion 12 and detecting fine particles on the detection region Ar, the detectable particle diameter of the dust sensor 8 is maintained. It is possible to discriminate a particle size different from the particle size corresponding to the threshold value VA and the threshold value VB.

(3) Fine particles having a large particle size that cannot be reached in the detection region Ar only by the updraft Au can be stably detected by the downdraft Ad.

(4) Fine particles having a wide particle size can be stably detected without changing the detection sensitivity of the light receiving element 15.

(5) Fine particles having a wide particle size can be stably detected without changing the light emitting intensity of the light emitting element 16.

The above embodiment may be changed as follows.

The threshold value VA was set as a threshold value for determining whether or not the signal was a signal in which fine particles exceeding 1 μm were detected in the state of the updraft Au. Further, the threshold value VB was set as a threshold value for determining whether or not the signal detected fine particles exceeding 2 μm in the state of the updraft Au. However, the setting of the threshold value is not limited to this, and it is sufficient if the particle size to be detected can be determined.

-As shown in FIG. 9, the Peltier element 22 may be used instead of the airflow control fan. The Peltier element 22 may be controlled by the control unit to alternately perform the heat generation operation and the cooling operation to generate the updraft Au and the downdraft Ad. The reason is that the fan motor 5 does not generate wind noise and the quietness can be improved.

As described above, since the air purifier according to the present invention can improve the detection accuracy of fine particles in the dust sensor, the above configuration can be applied when the dust sensor is used in, for example, another air conditioner.

1 Body case 2 Suction port 3 Blowout port 4 Filter (air purifier)
5 Fan motor (blower, air volume changing means)
7 Louver 8 Dirt detector (dust sensor)
10 Airflow control fan (updraft generating means / downdraft generating means)
21 Control unit (airflow control device)
22 Heat generation means / cooling means (Peltier element)
Ar detection area Au updraft Ad downdraft

Claims (4)

A main body case with a suction port and an outlet, and
An air blower that sucks air from the suction port and blows it out from the outlet.
An air purifying unit provided in the main body case for purifying the air flowing in from the suction port, and an output corresponding to the particle size of the fine particles by detecting fine particles contained in the air flowing in from the suction port in the detection region. A dirt detector that outputs a signal and
An air purifier having a control unit that determines dirt based on the output signal of the dirt detection unit.
An updraft generating means for guiding the air with an updraft to the detection region,
A downdraft generating means for guiding the air with a downdraft to the detection region,
An airflow control device that controls the updraft generating means and the downdraft generating means so that the downdraft and the updraft are alternately guided to the detection region.
With
The control unit
It has a threshold value corresponding to a predetermined particle size,
Using the output signal during the updraft, the output signal during the downdraft, and the threshold value output from the dirt detection unit, it is possible to determine another particle size larger than the predetermined particle size for the fine particles contained in the air. An air purifier characterized by The air purifier according to claim 1, wherein the updraft generating means and the downdraft generating means are composed of an airflow control fan capable of forward and reverse rotation. The first aspect of claim 1, wherein the updraft generating means is composed of a heat generating means for generating an updraft by heat generation, and the downdraft generating means is composed of a cooling means for generating a downdraft by cooling. Air cleaner. The air purifier according to claim 3, wherein the heat generating means and the cooling means are composed of a Peltier element.

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