# US 11,099,112 B2 · Dust measurement device and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,099,112 B2 - Document ID: US11099112B2 - Status: Granted - Kind: B2 - Application number: 16/605,912 - Filed: 2018-03-09 - Published: 2021-04-08 - Granted: 2021-08-24 - Earliest claimed: 2017-04-20 - Assignees: LG Ei.Fctronics Inc. - Applicants: LG Electronics Inc. - Inventors: Chulwoo Park; Bongjo Sung - Web page: https://patentgrep.com/patent/US11099112B2 ## CPC - G01N 15/0205: by optical means - G01N 15/02: Investigating particle size or size distribution (by measuring osmotic pressure G01N7/10; investigating sedimentation of particle suspensions G01N15/04; investigating individual particles G01N15/10) - G01N 15/0656: {using electric, e.g. electrostatic methods or magnetic methods (by investigating individual particles G01N15/1031, G01N15/12)} - G01N 27/04: by investigating resistance - G01N 15/075: by optical means - G01N 2015/0038: {Investigating nanoparticles} - G01N 2015/0277: {Average size only} - G01N 2015/0283: {using control of suspension concentration} - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract The present invention relates to a dust measurement device and method which can increase the accuracy of dust measurement by deriving a mass concentration on the basis of a number concentration distribution according to particle sizes. The dust measurement device of the present invention comprises: a charging unit for charging a feed material with electrical charges; a first dust collecting unit including a first and a second dust collecting electrode which are spaced apart from each other, through which the material passes, and to which different voltages are applied; a second dust collecting unit for collecting the material which has passed through the first dust collecting unit; a current measurement unit for measuring current flowing through the second dust collecting unit; and a control unit for calculating a mass concentration of the material by using the value of the current measured by the current measurement unit and adjusting voltages applied to the charging unit and the first dust collecting unit on the basis of the mass concentration. ## Claims ### Claim 1 A dust measuring apparatus comprising: an electrifier for generating plasma regions to electrify introduced dust; a first dust collector including first and second dust collecting electrodes arranged to be spaced apart from each other, wherein different voltages are respectively applied to the first and second dust collecting electrodes such that the first and second dust collecting electrodes collect the electrified dust; a second dust collector for collecting the dust passing through the first dust collector; a current measuring unit for measuring a current flowing in the second dust collector; and a controller configured to: use a current value measured in the current measuring unit to calculate a total number concentration and an average particle size of the dust; use the calculated total number concentration and average particle size to calculate a number concentration distribution based on a particle size; calculate a mass concentration of the dust based on the calculated number concentration distribution; and adjust voltages respectively applied to the electrifier and to the first dust collector based on the mass concentration. ### Claim 2 (depends on 1) The dust measuring apparatus of claim 1, wherein the controller is configured to: measure a first current flowing in the second dust collector when a voltage is not applied to the first dust collector; measure a second current flowing in the second dust collector when the voltage is applied to the first dust collector; and calculate the mass concentration using the first and second currents. ### Claim 3 (depends on 1) The dust measuring apparatus of claim 1, wherein the total number concentration is calculated using a following equation 1, and the average particle size is calculated using a following equation 2: N = S N ⁡ ( I 1 - I 2 ) ( 1 ) d p , av = S dp ⁢ I 1 I 1 - I 2 ( 2 ) wherein in the equations 1 and 2, Ii denotes the first current, I2 denotes the second current, N denotes the total number concentration of the dust, SN denotes a number concentration constant, dp,av denotes the average particle size of the dust, and Sap denotes an average particle size constant. ### Claim 4 (depends on 1) The dust measuring apparatus of claim 1, wherein the controller is configured to increase the voltages respectively applied to the electrifier and to the first dust collector when the mass concentration is higher than a predetermined reference value. ### Claim 5 (depends on 1) The dust measuring apparatus of claim 1, further comprising: a fan module for moving the dust from the electrifier toward the second dust collector, wherein the controller is configured to control an operation of the fan module based on the mass concentration. ### Claim 6 (depends on 5) The dust measuring apparatus of claim 5, wherein the controller is configured to increase an amount of air generated in the fan module when the mass concentration is higher than a predetermined reference value. ### Claim 7 (depends on 1) The dust measuring apparatus of claim 1, wherein the second dust collector includes a filter formed in a mesh shape and made of a metal material, wherein the filter is electrically connected to the current measuring unit, and wherein the current measuring unit measures a current flowing through the filter. ### Claim 8 (depends on 1) The dust measuring apparatus of claim 1, wherein the electrifier includes a first electrode and a second electrode, wherein a voltage is applied to the first electrode, wherein the second electrode includes first and second portions respectively disposed above and below the first electrode, and wherein the plasma regions are respectively defined between the first electrode and the first and second portions of the second electrode. ### Claim 9 A method for measuring dust of a dust measuring apparatus including an electrifier for electrifying introduced dust, a first dust collector for collecting the electrified dust, and a second dust collector for collecting the dust passing through the first dust collector, the method comprising: generating plasma regions in the electrifier to electrify introduced dust; measuring a first current flowing in the second dust collector when a first voltage is applied to the electrifier and a second voltage is not applied to the first dust collector; measuring a second current flowing in the second dust collector when the first voltage is applied to the electrifier and the second voltage is applied to the first dust collector; and using the first current and the second current to calculate a total number concentration and an average particle size of the dust, using the calculated total number concentration and average particle size to calculate a number concentration distribution based on a particle size, and calculating a mass concentration of the dust based on the calculated number concentration distribution. ### Claim 10 (depends on 9) The method of claim 9, further comprising: adjusting voltages respectively applied to the electrifier and to the first dust collector based on the mass concentration. ### Claim 11 (depends on 10) The method of claim 10, wherein the adjusting of the voltages respectively applied to the electrifier and to the first dust collector includes: increasing the voltages respectively applied to the electrifier and to the first dust collector when the mass concentration is higher than a predetermined reference value. ### Claim 12 (depends on 9) The method of claim 9, wherein the measuring of the first current includes: applying a third voltage to the first dust collector, wherein the third voltage is smaller than the second voltage. ### Claim 13 (depends on 9) The method of claim 9, wherein the total number concentration is calculated using a following equation 1, and the average particle size is calculated using a following equation 2: N = S N ⁡ ( I 1 - I 2 ) ( 1 ) d p , av = S dp ⁢ I 1 I 1 - I 2 ( 2 ) wherein in the equations 1 and 2, I1 denotes the first current, I2 denotes the second current, N denotes the total number concentration of the dust, SN denotes a number concentration constant, dp,av denotes the average particle size of the dust, and Sdp denotes an average particle size constant. ### Claim 14 (depends on 9) The method of claim 9, further comprising: moving the dust from the electrifier toward the second dust collector using a fan module; and controlling an operation of the fan module based on the mass concentration. ### Claim 15 (depends on 14) The method of claim 14, wherein the controlling of the operation of the fan module based on the mass concentration includes: increasing an amount of air generated in the fan module when the mass concentration is higher than a predetermined reference value. ### Claim 16 (depends on 9) The method of claim 9, wherein the second dust collector includes a filter formed in a mesh shape and made of a metal material, and wherein the first and second currents are measured by a current measuring unit measuring a current flowing in the filter. ### Claim 17 (depends on 9) The method of claim 9, wherein the electrifier includes a first electrode and a second electrode, wherein the first voltage is applied to the first electrode, wherein the second electrode includes first and second portions respectively disposed above and below the first electrode portion, and wherein the plasma regions are respectively defined between the first electrode and the first and second portions of the second electrode. ### Claim 18 (depends on 9) The method of claim 9, further comprising: detecting light scattered on the dust by a particulate matter (PM) sensor to calculate a concentration of the dust, wherein the calculating of the mass concentration includes: calculating the mass concentration using a value measured by the PM sensor and the first and second currents.