Particle sensor and ion generator
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- SHARP SEMICON INNOVATION CORP TENRI CITY
- Filing Date
- 2022-09-01
- Publication Date
- 2026-08-05
Smart Images
Figure 0007900982000001 
Figure 0007900982000002 
Figure 0007900982000003
Abstract
Description
Technical Field
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[0001] The present disclosure relates to a particle sensor and an ion generator.
Background Art
[0002] A particle sensor that detects the amount of particles by a light scattering method can generally detect only the amount of particles having a size of 1 / 3 or more of the wavelength of the light used. Therefore, the particle sensor can generally detect only the amount of particles having a size of 0.3 μm or more.
[0003] This disclosure has been made in view of this problem. One aspect of this disclosure aims to provide, for example, a particle sensor and an ion generator capable of detecting the amount of particles having a small size. [Means for solving the problem]
[0007] A particle sensor according to one aspect of the present disclosure comprises an ion emitter that emits ions into a detection area, an ion counter that detects the amount of ions in the detection area, and a processing unit that acquires the amount of decrease of the ion amount from a reference ion amount.
[0008] An ion generator according to another aspect of the present disclosure comprises a particle sensor according to an aspect of the present disclosure, a fan that generates an airflow blown into an external space, and an ion generator that generates emitted ions released into the external space, wherein air sampled from the external space is guided to the detection area. [Brief explanation of the drawing]
[0009] [Figure 1] This figure schematically illustrates the particle sensor of the first embodiment. [Figure 2] This figure shows the processing performed by the processing unit provided in the particle sensor of the first embodiment. [Figure 3] This figure schematically illustrates the ion emitter and ion counter provided in the particle sensor of the first embodiment. [Figure 4] This is a flowchart showing the process of detecting the amount of particles using the particle sensor in the first embodiment. [Figure 5] This figure schematically illustrates the ion generator of the first embodiment. [Figure 6] This figure schematically illustrates the particle sensor of the second embodiment. [Figure 7] This figure shows the processing performed by the processing unit provided in the particle sensor of the second embodiment. [Figure 8] This flowchart shows the flow of particle quantity detection and ion addition amount determination using the particle sensor in the second embodiment. [Figure 9] This figure schematically illustrates the ion generator of the second embodiment. [Figure 10] This figure schematically illustrates the ion generator of the third embodiment. [Figure 11] This flowchart shows the processing flow using the ion generator of the third embodiment. [Modes for carrying out the invention]
[0010] The embodiments of this disclosure will be described below with reference to the drawings. In the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant descriptions are omitted.
[0011] 1. First Embodiment 1.1 Particle Sensor Figure 1 is a schematic diagram illustrating the particle sensor of the first embodiment.
[0012] The particle sensor 1 of the first embodiment shown in Figure 1 detects the amount of particles 104 in sampled air. The particle sensor 1 can detect the amount of particles 104 with high accuracy even when the particles 111 in the air include fine particles of a small size. For example, the particle sensor 1 can detect the amount of particles 104 with high accuracy even when the particles 111 include fine particles with a size of 0.3 μm or less.
[0013] As shown in Figure 1, the particle sensor 1 comprises a housing 121, an ion emitter 122, an ion counter 123, and a processing unit 124.
[0014] The housing 121 houses the ion emitter 122 and the ion counter 123. The housing 121 may also house the processing unit 124.
[0015] The housing 121 is formed with an opening 121a, an opening 121b, and a flow path 121c. The flow path 121c extends from the opening 121a to the opening 121b. Thus, the flow path 121c can guide the air sampled from the opening 121a to the opening 121b.
[0016] The ion emitter 122 and the ion counter 123 are separated from each other. Thus, a gap is formed between the ion emitter 122 and the ion counter 123. The formed gap is used as a detection region 121d. The space other than the gap may be used as the detection region 121d. The detection region 121d is within the flow path 121c. Thus, the flow path 121c can guide the air sampled from the opening 121a through the detection region 121d to the opening 121b. Thus, the sampled air can be guided to the detection region 121d.
[0017] The ion emitter 122 emits ions 112 into the detection region 121d.
[0018] The ion counter 123 detects the ion amount 101 in the detection region 121d. The detected ion amount 101 is the amount of the ions 112 that have not reacted with the particles 111 and disappeared among the ions 112 emitted into the detection region 121d by the ion emitter 122.
[0019] FIG. 2 is a diagram showing the content of the processing performed by the processing unit provided in the particle sensor of the first embodiment.
[0020] The particle sensor 1 does not directly detect the particle amount 104, but indirectly detects the particle amount 104 from the detected ion amount 101.
[0021] To this end, as shown in Figure 2, the processing unit 124 obtains the decrease 103 of the detected ion amount 101 from the reference ion amount 102. The decrease 103 is obtained by subtracting the ion amount 101 from the reference ion amount 102. The reference ion amount 102 is the amount of ions detected by the ion counter 123 when no particles 111 are present in the detection area 121d. The reference ion amount 102 is the amount of ions 112 emitted by the ion emitter 122.
[0022] The particles 111 present in the detection region 121d are suspended in the air present in the detection region 121d. Therefore, the particles 111 present in the detection region 121d readily react with the ions 112 released into the detection region 121d, causing the reacted ions 112 to disappear. For this reason, the acquired reduction amount 103 has a positive correlation with the particle amount 104.
[0023] Therefore, the processing unit 124 obtains the particle quantity 104 from the acquired reduction amount 103. The processing unit 124 increases the particle quantity 104 it obtains as the reduction amount 103 increases.
[0024] The processing unit 124 includes a microcontroller. The microcontroller includes a processor, memory, and an interface. The processor causes the microcontroller to perform the processing that the processing unit 124 would normally perform by executing a program stored in memory. The processing unit 124 may include a dedicated electronic circuit, and this dedicated electronic circuit may perform all or part of the processing.
[0025] 1.2 Ion emitter Figure 3 schematically illustrates the ion emitter and ion counter provided in the particle sensor of the first embodiment.
[0026] As shown in Figure 3, the ion emitter 122 comprises a power supply 131, a switching element 132, a pulse transformer 133, a first diode 134, a second diode 135, a first needle electrode 136, a second needle electrode 137, and a counter electrode 138.
[0027] As shown in Figure 3, the power supply 131 comprises a positive electrode 141 and a negative electrode 142. The power supply 131 generates a DC voltage between the positive electrode 141 and the negative electrode 142.
[0028] As shown in Figure 3, the switching element 132 includes terminals 151 and 152. The switching element 132 can be in a closed state or an open state. When the switching element 132 is in a closed state, terminal 152 conducts with terminal 151. When the switching element 132 is in an open state, terminal 152 does not conduct with terminal 151. The switching element 132 is a metal oxide semiconductor field-effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), etc.
[0029] As shown in Figure 3, the pulse transformer 133 comprises a primary winding 161 and a secondary winding 162. The primary winding 161 comprises terminals 171 and 172. The secondary winding 162 comprises terminals 181 and 182. The pulse transformer 133 generates a pulse between terminals 181 and 182 having a voltage corresponding to the voltage of the pulse generated between terminals 171 and 172. The pulse transformer 133 is a step-up transformer. Therefore, the voltage of the pulse generated between terminals 181 and 182 is higher than the voltage of the pulse generated between terminals 171 and 172.
[0030] As shown in Figure 3, the first diode 134 comprises an anode 191 and a cathode 192. The first diode 134 allows current to pass from the anode 191 to the cathode 192. However, the first diode 134 blocks current from the cathode 192 to the anode 191.
[0031] As shown in Figure 3, the second diode 135 comprises an anode 201 and a cathode 202. The second diode 135 allows current to pass from the anode 201 to the cathode 202. However, the second diode 135 blocks current from the cathode 202 to the anode 201.
[0032] When a positive pulse is applied between the first needle electrode 136 and the counter electrode 138, the first needle electrode 136 generates a discharge between the first needle electrode 136 and the counter electrode 138, thereby generating positive ions 211 between the first needle electrode 136 and the counter electrode 138.
[0033] When a negative pulse is applied between the second needle electrode 137 and the counter electrode 138, the second needle electrode 137 generates a discharge between the second needle electrode 137 and the counter electrode 138, thereby generating negative ions 212 between the second needle electrode 137 and the counter electrode 138.
[0034] The negative terminal 142 of the power supply 131 is electrically grounded. The positive terminal 141 of the power supply 131 is electrically connected to terminal 151 of the switching element 132. Terminal 152 of the switching element 132 is electrically connected to terminal 171 of the primary winding 161. Terminal 172 of the primary winding 161 is electrically grounded and electrically connected to the negative terminal 142 of the power supply 131. As a result, the power supply 131, the switching element 132, and the primary winding 161 are electrically connected in series. In addition, the power supply 131, the switching element 132, and the primary winding 161 are inserted into a loop-shaped conductive path. When the switching element 132 is in a closed state, a closed circuit is formed and current flows through the power supply 131, the switching element 132, and the primary winding 161. When the switching element 132 is in an open state, an open circuit is formed and no current flows through the power supply 131, the switching element 132, and the primary winding 161.
[0035] Terminal 181 of the secondary winding 162 is electrically connected to the anode 191 of the first diode 134 and the cathode 202 of the second diode 135. The cathode 192 of the first diode 134 is electrically connected to the first needle electrode 136. The anode 201 of the second diode 135 is electrically connected to the second needle electrode 137. The counter electrode 138 is electrically connected to terminal 182 of the secondary winding 162. As a result, terminal 181 is electrically connected to the first needle electrode 136 via the first diode 134. In addition, terminal 181 is electrically connected to the second needle electrode 137 via the second diode 135.
[0036] When the switching element 132 changes from an open state to a closed state, or from a closed state to an open state, the current flowing through the primary winding 161 changes abruptly. As a result, a pulse accompanied by ringing is generated between terminals 171 and 172 of the primary winding 161. Consequently, a pulse accompanied by ringing is also generated between terminals 181 and 182 of the secondary winding 162. The positive pulse generated between terminals 181 and 182 is transmitted through the first diode 134 to the area between the first needle electrode 136 and the counter electrode 138. As a result, a positive pulse is applied between the first needle electrode 136 and the counter electrode 138, and positive ions 211 are generated between the first needle electrode 136 and the counter electrode 138. The negative pulse generated between terminals 181 and 182 is transmitted via the second diode 135 to the space between the second needle electrode 137 and the counter electrode 138. This applies a negative pulse between the second needle electrode 137 and the counter electrode 138, generating negative ions 212 between them. The generated positive ions 211 and negative ions 212 are carried to the detection region 121d by the airflow 222. As a result, ions 112, consisting of positive ions 211 and negative ions 212, are released into the detection region 121d. All or part of the released ions 112 adhere to particles 111 present in the detection region 121d and disappear.
[0037] The discharges generated between the first needle electrode 136 and the counter electrode 138, and the discharges generated between the second needle electrode 137 and the counter electrode 138, are controlled so that the amount of ions 112 released remains constant.
[0038] The ion emitter 122 may have a structure different from the structure shown in Figure 3.
[0039] 1.3 Ion Counter As shown in Figure 3, the ion counter 123 includes a first ion counter 231 and a second ion counter 232.
[0040] The first ion counter 231 detects the amount of positive ions in the detection region 121d using the Gerdien method. The second ion counter 232 detects the amount of negative ions in the detection region 121d using the Gerdien method. As a result, the ion counter 123 can detect the total ion amount 101, which is the sum of the positive and negative ion amounts in the detection region 121d.
[0041] As shown in Figure 3, the first ion counter 231 comprises a first power supply 241, a first double cylinder 242, and a first current sensor 243.
[0042] As shown in Figure 3, the first power supply 241 comprises a positive electrode 251 and a negative electrode 252. The first power supply 241 generates a DC voltage between the positive electrode 251 and the negative electrode 252.
[0043] As shown in Figure 3, the first double cylinder 242 comprises an inner cylinder 261 and an outer cylinder 262. The first double cylinder 242 generates an electric field between the inner cylinder 261 and the outer cylinder 262 in accordance with the voltage applied between them.
[0044] As shown in Figure 3, the first current sensor 243 includes terminals 271 and 272, and detects the current value of the current flowing between terminals 271 and 272.
[0045] The positive electrode 251 of the first power supply 241 is electrically connected to the inner cylinder 261 of the first double cylinder 242. The negative electrode 252 of the first power supply 241 is grounded. The outer cylinder 262 of the first double cylinder 242 is electrically connected to terminal 271 of the first current sensor 243. Terminal 272 of the first current sensor 243 is grounded and electrically connected to the negative electrode 252 of the first power supply 241. As a result, the outer cylinder 262 is grounded via the first current sensor 243 and electrically connected to the negative electrode 252 via the first current sensor 243. As a result, the DC voltage generated between the positive electrode 251 and the negative electrode 252 is applied between the inner cylinder 261 and the outer cylinder 262. In addition, the current value of the current flowing from the outer cylinder 262 to the negative electrode 252 is detected by the first current sensor 243. The amount of positive ions can be obtained from the detected current value.
[0046] As shown in Figure 3, the second ion counter 232 includes a second power supply 281, a second double cylinder 282, and a second current sensor 283.
[0047] As shown in Figure 3, the second power supply 281 comprises a positive electrode 291 and a negative electrode 292. The second power supply 281 generates a DC voltage between the positive electrode 291 and the negative electrode 292.
[0048] As shown in Figure 3, the second double cylinder 282 comprises an inner cylinder 301 and an outer cylinder 302. The second double cylinder 282 generates an electric field between the inner cylinder 301 and the outer cylinder 302 in accordance with the voltage applied between them.
[0049] As shown in Figure 3, the second current sensor 283 includes terminals 311 and 312, and detects the current value of the current flowing between terminals 311 and 312.
[0050] The negative electrode 292 of the second power supply 281 is electrically connected to the inner cylinder 301 of the second double cylinder 282. The positive electrode 291 of the second power supply 281 is grounded. The outer cylinder 302 of the second double cylinder 282 is electrically connected to terminal 311 of the second current sensor 283. Terminal 312 of the second current sensor 283 is grounded and electrically connected to the positive electrode 291 of the second power supply 281. As a result, the outer cylinder 302 is grounded via the second current sensor 283 and electrically connected to the positive electrode 291 via the second current sensor 283. As a result, the DC voltage generated between the positive electrode 291 and the negative electrode 292 is applied between the outer cylinder 302 and the inner cylinder 301. In addition, the current value of the current flowing from the positive electrode 291 to the outer cylinder 302 is detected by the second current sensor 283. The amount of negative ions can be obtained from the detected current value.
[0051] The ion counter 123 may have a structure different from the structure shown in Figure 3.
[0052] 1.4 Flowchart for detecting particle quantity Figure 4 is a flowchart showing the flow of particle quantity detection by the particle sensor in the first embodiment.
[0053] The particle sensor 1 performs steps S101 to S105 shown in Figure 4.
[0054] In step S101, the ion emitter 122 generates ions 112.
[0055] In the subsequent step S102, the generated ions 112 are carried by the airflow 222 to the detection area 121d. As a result, the ion emitter 122 releases the ions 112 into the detection area 121d.
[0056] In the following step S103, air is introduced into the detection area 121d. All or part of the emitted ions 112 attach to particles 111 floating in the introduced air and disappear.
[0057] In the following step S104, the ion counter 123 detects the amount of ions 101 in the detection area 121d. The detected amount of ions 101 is the amount of ions 112 that did not adhere to the particles 111 and did not disappear.
[0058] In the subsequent step S105, the processing unit 124 obtains the decrease 103 of the detected ion amount 101 from the reference ion amount 102, and obtains the particle amount 104 from the obtained decrease 103.
[0059] 1.5 Ion Generator Figure 5 is a schematic diagram illustrating the ion generator of the first embodiment.
[0060] The ion generator 10 shown in Figure 5 generates emitted ions 331 that are released into the external space 321. The emitted ions 331 purify the air 332 present in the external space 321. For example, the emitted ions 331 disinfect the air 332. Therefore, the ion generator 10 is an air purifier. The external space 321 is the space inside the room where the ion generator 10 is placed, etc.
[0061] As shown in Figure 5, the ion generator 10 includes the particle sensor 1 of the first embodiment. The ion generator 10 also includes a housing 341, a filter 342, a fan 343, an ion generator 344, and a control unit 345. The particle sensor 1 may be provided in a device other than the ion generator 10. The particle sensor 1 may also be used on its own.
[0062] The housing 341 houses the particle sensor 1, filter 342, fan 343, ion generator 344, and control unit 345.
[0063] The housing 341 has openings 341a, 341b, a channel 341c, and a channel 341d.
[0064] The flow path 341c extends from the opening 341a to the opening 121a of the particle sensor 1. This allows the flow path 341c to guide air 332 from the opening 341a to the opening 121a.
[0065] The flow path 341d extends from the opening 121b of the particle sensor 1 to the opening 341b. This allows the flow path 341d to guide air 332 from the opening 121b to the opening 341b.
[0066] Openings 341a and 341b are exposed to the external space 321. This allows air 332 to be guided from the external space 321 to the external space 321 via opening 341a, flow path 341c, opening 121a of particle sensor 1, flow path 121c of particle sensor 1, opening 121b of particle sensor 1, flow path 341d, and opening 341b. This allows air 332 sampled from the external space 321 to be guided to the detection area 121d located within flow path 121c.
[0067] The housing 341 has openings 341e, 341f, and a flow path 341g. The flow path 341g runs from opening 341e through a filter 342, a fan 343, and an ion generator 344 to opening 341f. This allows the flow path 341g to guide air 332 from opening 341e through the filter 342, a fan 343, and an ion generator 344 to opening 341f. Openings 341e and 341f are exposed to the external space 321. This allows the flow path 341g to guide air 332 from the external space 321 through opening 341e, a filter 342, a fan 343, an ion generator 344, and opening 341f to the external space 321.
[0068] Fan 343 generates an airflow 351. The generated airflow 351 travels from the external space 321 through the opening 341e, filter 342, fan 343, ion generator 344, and opening 341f back to the external space 321. Therefore, the airflow 351 is blown out into the external space 321.
[0069] The ion generator 344 generates emitted ions 331. The generated emitted ions 331 are carried to the external space 321 by the generated airflow 351 and released into the external space 321.
[0070] The filter 342 passes the generated airflow 351 through. This allows the filter 342 to filter out the particles 111 carried by the airflow 351. The filter 342 can be a dust collection filter, a deodorizing filter, a high-efficiency particulate air (HEPA) filter, etc.
[0071] The control unit 345 controls at least one selected from the group consisting of the fan 343 and the ion generator 344 based on the acquired particle quantity 104.
[0072] A large reduction of 103 means that there is a large amount of particles 111 suspended in the air 332 that have not reacted with the emitted ions 331. Therefore, a large reduction of 103 means that the amount of emitted ions 331 is small relative to the amount of particles 111, that is, the air 332 is not sufficiently purified. For this reason, the control unit 345 performs feedback control on at least one selected from the group consisting of the fan 343 and the ion generator 344 so that the air 332 is purified more as the reduction of 103 increases. For example, the control unit 345 increases the airflow rate of the generated airflow 351 of the fan 343 as the reduction of 103 increases, thereby increasing the amount of particles 111 filtered by the filter 342. To this end, the control unit 345 increases the airflow rate of the generated airflow 351 of the fan 343 as the detected particle amount 104 increases. Alternatively, the control unit 345 increases the amount of emitted ions 331 generated by the ion generator 344 as the reduction of 103 increases. To that end, the control unit 345 causes the ion generator 344 to increase the amount of emitted ions 331 as the detected particle quantity 104 increases.
[0073] The control unit 345 includes a microcontroller. The microcontroller includes a processor, memory, and an interface. The processor causes the microcontroller to perform the processing that would otherwise be performed by the control unit 345 by executing a program stored in memory. The control unit 345 may include a dedicated electronic circuit, and this dedicated electronic circuit may perform all or part of the processing.
[0074] In the ion generator 10 of the first embodiment, the effect of the emitted ions 331 on the air 332 present in the external space 321 can be determined by the effect of the ions 112 on the air 332 sampled from the external space 321. Therefore, the former effect can be quantitatively determined. This makes it possible to control the amount of emitted ions 331 to an amount appropriate for the level of contamination of the air 332. In addition, the airflow rate of the air 351 can be controlled to an airflow rate appropriate for the level of contamination of the air 332. This makes it possible to suppress the power consumption and noise of the ion generator 10. Furthermore, it is possible to shorten the time required to purify the air 332.
[0075] 2. Second Embodiment The following describes the differences between the second embodiment and the first embodiment. For aspects not described, the same configuration as that used in the first embodiment is used in the second embodiment.
[0076] Figure 6 is a schematic diagram illustrating the particle sensor of the second embodiment. Figure 7 is a diagram showing the processing performed by the processing unit provided in the particle sensor of the second embodiment.
[0077] The amount of ions 112 that react with particles 111 suspended in air 332 sampled from the external space 321 has a positive correlation with the amount of emitted ions 331 that can react with particles 111 suspended in air 332 present in the external space 321.
[0078] Therefore, in the particle sensor 2 of the second embodiment, as shown in Figures 6 and 7, the processing unit 124 obtains the amount of ions added 361 from the amount of decrease 103. The processing unit 124 increases the amount of ions added 361 obtained as the amount of decrease 103 increases.
[0079] Figure 8 is a flowchart showing the flow of particle quantity detection and ion addition amount determination using the particle sensor in the second embodiment.
[0080] The particle sensor 2 performs steps S111 to S116 shown in Figure 8.
[0081] In steps S111 to S115, the same processes as those performed in steps S101 to S105 shown in Figure 4 are executed.
[0082] In step S116, the processing unit 124 obtains the amount of ions added 361 from the acquired amount of decrease 103.
[0083] Figure 9 is a schematic diagram illustrating the ion generator of the second embodiment.
[0084] As shown in Figure 9, the ion generator 20 of the second embodiment is equipped with the particle sensor 2 of the second embodiment.
[0085] In the ion generator 20 of the second embodiment, the control unit 345 controls the ion generator 344 based on the determined ion addition amount 361. The control unit 345 controls the ion generator 344 so that the amount of emitted ions 331 released into the external space 321 increases by the ion addition amount 361.
[0086] If the acquired decrease amount 103 is not 0, that is, if the detected ion amount 101 is less than the reference ion amount 102, then the amount of emitted ions 331 released into the external space 321 is less than the appropriate amount. For this reason, the processing unit 124 increases the ion addition amount 361 to greater than 0. As a result, the control unit 345 controls the ion generator 344 so that the ion generator 20 releases additional emitted ions 331. For example, if the reference ion amount 102 is "100", the detected ion amount 101 is "50", which is less than the reference ion amount 102, the decrease amount 103 is "50", and half of the ions 112 released by the ion emitter 122 have disappeared, then the air 332 in the external space 321 is not clean and particles 111 are present in the air 332. For this reason, the control unit 345 causes the ion generator 20 to release additional emitted ions 331.
[0087] On the other hand, if the decrease amount 103 is 0, that is, if the detected ion amount 101 is equal to the reference ion amount 102, then the amount of released ions 331 released into the external space 321 is appropriate. For this reason, the processing unit 124 sets the additional ion amount 361 to 0. As a result, the control unit 345 controls the ion generator 344 so that the ion generator 20 does not release additional ions 331. For example, if the reference ion amount 102 is "100", the detected ion amount 101 is "100", which is equal to the reference ion amount 102, the decrease amount 103 is "0", and all of the ions 112 released by the ion emitter 122 remain without disappearing, then the air 332 present in the external space 321 is already clean. For this reason, the control unit 345 prevents the ion generator 20 from releasing additional ions 331.
[0088] Generally, air purifiers detect the amount of particles suspended in the air and control the airflow based on the detected amount. Furthermore, if an air purifier has an ion-generating function, it controls the amount of ions generated according to user operations. However, when the amount of ions generated is controlled according to user operations, it is often difficult to properly control the amount of ions generated.
[0089] In contrast, in the ion generator 20 of the second embodiment, the ion emitter 122 and detection area 121d of the particle sensor 2 are a microcosm of the ion generator 20 and the external space 321. Therefore, the effect of the emitted ions 331 released by the ion generator 20 on particles 111 suspended in the air 332 present in the external space 321 can be estimated with high accuracy from the effect of the ions 112 released by the ion emitter 122 of the particle sensor 2 on particles 111 suspended in the air 332 present in the detection area 121d. In the ion generator 20 of the second embodiment, this can be used to appropriately control the amount of emitted ions 331. This makes it possible to control the amount of emitted ions 331 to an amount suitable for the level of contamination in the air 332. Furthermore, the time required to purify the air 332 can be shortened.
[0090] 3. Third Embodiment The differences between the third embodiment and the first embodiment will be explained below. For aspects not explained, the same configuration as that used in the first embodiment will be used in the third embodiment.
[0091] Figure 10 is a schematic diagram illustrating the ion generator of the third embodiment.
[0092] As shown in Figure 10, the ion generator 30 of the third embodiment is equipped with a dust sensor 371.
[0093] The dust sensor 371 detects the amount of dust 381 in the sampled air 332. The detected amount of dust 381 is the amount of dust 385, which are large particles contained in the particles 111. For example, the detected amount of dust 381 is the amount of dust 385 that are particles with a size of 0.3 μm or larger.
[0094] As shown in Figure 10, the dust sensor 371 comprises a housing 391, a light source 392, a light receiving element 393, and a processing unit 394.
[0095] The housing 391 houses the light source 392 and the light receiving element 393. The housing 121 may house the processing unit 394.
[0096] The housing 391 has openings 391a, 391b, and a flow path 391c. The flow path 391c extends from opening 391a to opening 391b. This allows the flow path 391c to guide air 332 from opening 391a to opening 391b. A dust detection area 391d is located within the flow path 391c. This allows the flow path 391c to guide air 332 from opening 391a through the dust detection area 391d to opening 391b. This allows the sampled air 332 to be guided to the dust detection area 391d.
[0097] The light source 392 emits light toward the dust detection area 391d. The light source 392 is a light-emitting diode, incandescent bulb, mercury lamp, electroluminescent element, etc.
[0098] The light-receiving element 393 detects a light intensity of 400 arriving from the dust detection area 391d. The light-receiving element 393 is a photodiode, photoresistor, etc.
[0099] The processing unit 394 obtains the amount of dust 381 in the dust detection area 391d from the detected intensity 400. As a result, the dust sensor 371 detects the amount of dust 381 in the dust detection area 391d.
[0100] The processing unit 394 includes a microcontroller. The microcontroller includes a processor, memory, and an interface. The processor causes the microcontroller to perform the processing that the processing unit 394 would normally perform by executing a program stored in memory. The processing unit 394 may include a dedicated electronic circuit, and this dedicated electronic circuit may perform all or part of the processing.
[0101] In the ion generator 30 of the third embodiment, the flow channels 341p, 341q, and 341r are formed in the housing 341.
[0102] The flow path 341p extends from the opening 341a to the opening 391a of the dust sensor 371. This allows the flow path 341p to guide air 332 from the opening 341a to the opening 391a.
[0103] The flow path 341q extends from the opening 391b of the dust sensor 371 to the opening 121a of the particle sensor 1. This allows the flow path 341q to guide air 332 from the opening 391b to the opening 121a.
[0104] The flow path 341r extends from the opening 121b of the particle sensor 1 to the opening 341b. This allows the flow path 341r to guide air 332 from the opening 121b to the opening 341b.
[0105] Openings 341a and 341b are exposed to the external space 321. This allows air 332 to be guided from the external space 321 to the external space 321 via opening 341a, flow path 341p, opening 391a of dust sensor 371, flow path 391c of dust sensor 371, opening 391b of dust sensor 371, flow path 341q, opening 121a of particle sensor 1, flow path 121c of particle sensor 1, opening 121b of particle sensor 1, and flow path 341r. This allows air 332 sampled from the external space 321 to be guided to the dust detection area 391d in flow path 391c and the detection area 121d in flow path 121c. Furthermore, the detection area 121d can allow air 332 that has passed through the dust detection area 391d to pass through. The dust sensor 371 does not increase or decrease the amount of particles 111 suspended in the air 332 passing through the dust detection area 391d. Therefore, by passing the air that has passed through the dust detection area 391d through the detection area 121d, both the particle amount 104 and the dust amount 381 can be detected with high accuracy.
[0106] In the ion generator 30 of the third embodiment, the control unit 345 controls at least one selected from the group consisting of a fan 343 and an ion generator 344 based on the acquired reduction amount 103 and dust amount 381.
[0107] In the third embodiment, the particle sensor 1 acquires a decrease amount 103 that has a positive correlation with the amount of particles 111 having various sizes. In addition, the dust sensor 371 acquires a dust amount 381, which is the amount of particles with a large size. Therefore, from the acquired decrease amount 103 and dust amount 381, it is possible to identify the characteristics of the particles 111, such as the size distribution of the particles 111 suspended in the air 332. For example, if the dust amount 381 is small and the decrease amount 103 is large, it can be identified that the particles 111 contain a large amount of particles with a size of 0.3 μm or less. Also, if the dust amount 381 is large and the decrease amount 103 is large, it can be identified that the particles 111 contain a large amount of particles with a size larger than 0.3 μm. If the dust amount 381 is large and the decrease amount 103 is small, it can be identified that the particles 111 contain a large amount of particles that do not react with ions 112.
[0108] Therefore, the control unit 345 controls at least one selected from the group consisting of the fan 343 and the ion generator 344 so that operation is performed in a manner suitable for the characteristics of the particles 111 that can be identified from the acquired reduction amount 103 and dust amount 381. This allows for appropriate control of the fan 343 and the ion generator 344. For example, if the dust amount 381 is large and the reduction amount 103 is large, the control unit 345 increases the airflow rate of the generated airflow 351 of the fan 343 and does not increase the amount of emitted ions 331 generated by the ion generator 344. Also, if the dust amount 381 is small and the reduction amount 103 is large, the control unit 345 increases the airflow rate of the generated airflow 351 of the fan 343 and increases the amount of emitted ions 331 generated by the ion generator 344.
[0109] Figure 11 is a flowchart showing the processing flow by the ion generator of the third embodiment.
[0110] The ion generator 30 of the third embodiment performs steps S121 to S128 shown in Figure 11.
[0111] In steps S121 to S125, the same processes as those performed in steps S101 to S105 shown in Figure 4 are executed.
[0112] In the following step S126, the dust sensor 371 detects the amount of dust 381. In the processing flow shown in Figure 11, step S126 is executed after steps S121 to S125. However, step S126 may be executed before steps S121 to S125, or simultaneously with steps S121 to S125. This is because the timing at which air 332 is introduced into the detection area 121d and the dust detection area 391d is almost simultaneous, and there is no need to perform either the acquisition of the reduction amount 103 or the detection of the amount of dust 381 beforehand.
[0113] In the subsequent step S127, the control unit 345 analyzes the air quality of the air 332 based on the reduction amount 103 and the dust amount 381. The air quality analyzed includes the characteristics of the particles 111 described above.
[0114] In the following step S128, the control unit 345 controls the fan 343 and the ion generator 344 based on the analyzed air quality.
[0115] This disclosure is not limited to the embodiments described above, and may be replaced with configurations that are substantially the same as those shown in the embodiments, configurations that produce the same effects, or configurations that can achieve the same purpose. [Explanation of symbols]
[0116] 1 Particle sensor, 2 Particle sensor, 10 Ion generator, 20 Ion generator, 30 Ion generator, 101 Ion quantity, 102 Reference ion quantity, 103 Decrease amount, 104 Particle quantity, 111 Particle, 112 Ion, 121 Housing, 121a Aperture, 121b Aperture, 121c Flow path, 121d Detection area, 122 Ion emitter, 123 Ion counter, 124 Processing unit, 131 Power supply, 132 Switching element, 133 Pulse transformer, 134 First diode, 135 Second diode, 136 First needle electrode, 137 Second needle electrode, 138 Counter electrode, 141 Positive electrode, 142 Negative electrode, 151 Terminal, 152 Terminal, 161 Primary winding, 162 Secondary winding, 171 Terminal, 172 Terminal, 181 Terminal, 182 Terminal, 191 Anode, 192 Cathode, 201 Anode, 202 Cathode, 211 Positive ion, 212 Negative ion, 222 Airflow, 231 First ion counter, 232 Second ion counter, 241 First power supply, 242 First double cylinder, 243 First current sensor, 251 Positive electrode, 252 Negative electrode, 261 Inner cylinder, 262 Outer cylinder, 271 Terminal, 272 Terminal, 281 Second power supply, 282 Second double cylinder, 283 Second current sensor, 291 Positive electrode, 292 Negative electrode, 301 Inner cylinder, 302 Outer cylinder, 311 Terminal, 312 Terminal, 321 External space, 331 Emitted ions, 332 Air, 341 Housing, 341a Aperture, 341b Aperture, 341c Flow path, 341d Flow path, 341e Aperture, 341f Aperture, 341g Flow path, 341p Flow path, 341q Flow path, 341r Flow path, 342 Filter, 343 Fan, 344 Ion generator, 345 Control unit, 351 Airflow, 361 Ion addition amount, 371 Dust sensor, 381 Dust amount, 385 Dust, 391 Housing, 391a Aperture, 391b Aperture, 391c Flow path, 391d Dust detection area, 392 Light source, 393 Photodetector, 394 Processing unit, 400 Intensity.
Claims
1. An ion emitter that releases ions into the detection area, An ion counter is provided, which is separated from the ion emitter, forms a gap between it and the ion emitter that constitutes the detection region, and detects the amount of ions in the detection region. A processing unit that obtains a reduction amount obtained by subtracting the amount of ions detected by the ion counter from the reference amount of ions when no airborne particles are present in the detection area, A particle sensor equipped with the following features.
2. The processing unit obtains the particle quantity from the reduction amount and increases the particle quantity as the reduction amount increases. The particle sensor according to claim 1.
3. The processing unit obtains an ion addition amount from the decrease amount, which indicates the increase in the amount of ions released by the ion generator that releases ions into the air guided to the detection area, and increases the ion addition amount as the decrease amount increases. The particle sensor according to claim 1.
4. A particle sensor according to any one of claims 1 to 3, A fan that generates an airflow that is blown into the outside space, An ion generator that generates emitted ions to be released into the aforementioned external space, Equipped with, The air sampled from the external space is guided to the detection area. Ion generator.
5. The particle sensor is the particle sensor described in claim 2, The system includes a control unit that controls at least one selected from the group consisting of the fan and the ion generator based on the particle quantity. The ion generator according to claim 4.
6. The particle sensor is the particle sensor described in claim 3, The system includes a control unit that controls the ion generator based on the amount of ions added. The ion generator according to claim 4.
7. A dust sensor that detects the amount of dust in the dust detection area. Equipped with, The aforementioned detection area allows air that has passed through the dust detection area to pass through. The ion generator according to claim 4.
8. The system includes a control unit that controls at least one selected from the group consisting of the fan and the ion generator based on the aforementioned reduction amount and the aforementioned dust amount. The ion generator according to claim 7.