# US 2013/0239802 A1 · Self-cleaning air filter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0239802 A1 - Document ID: US20130239802A1 - Status: Published application - Kind: A1 - Application number: 13/832,519 - Filed: 2013-03-15 - Published: 2013-09-19 - Earliest claimed: 2010-09-24 - Assignees: Maradyne Corporation - Inventors: Jason D. Troxell - Web page: https://patentgrep.com/patent/US20130239802A1 ## CPC - B01D 46/71: with pressurised gas, e.g. pulsed air - B01D 46/0086: {Filter condition indicators} - B01D 46/2403: {characterised by the physical shape or structure of the filtering element} - B01D 46/4272: {Special valve constructions adapted to filters or filter elements} - B01D 46/446: {by pressure measuring} - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) ## Abstract A system and method to control cleaning of an associated air filter apparatus is disclosed. Air flow across the associated air filter is estimated using a pressure sensor disposed at an inlet port of the associated air filter and a pressure sensor disposed at an outlet port of the associated air filter. Further, an optimal air flow across the associated air filter is calculated. The optimal air flow results in optimal filtering efficiency. The associated air filter is then periodically cleaned at a rate determined from the difference between the estimated air flow and the calculated optimal air flow to move air flow towards the optimal air flow. ## Claims ### Claim 1 A system for controlling cleaning of an associated air filter apparatus, said system comprising: processing circuitry configured to: estimate air flow across the associated air filter using a pressure sensor disposed at an inlet port of the associated air filter and a pressure sensor disposed at an outlet port of the associated air filter; calculate an optimal air flow across the associated air filter, the optimal air flow resulting in optimal filtering efficiency; and periodically clean the associated air filter at a rate determined from the difference between the estimated air flow and the calculated optimal air flow to move air flow towards the optimal air flow. ### Claim 2 (depends on 1) The system according to claim 1, wherein the estimated air flow and the calculated optimal air flow are defined in terms of differential pressure across the associated air filter. ### Claim 3 (depends on 1) The system according to claim 1, wherein the processing circuitry is configured to: estimate air flow across the associated air filter based on a ratio of: 1) pressure at the inlet port when the associated air filter is under full load and the associated air filter is clean and/or new; and 2) pressure at the inlet port. ### Claim 4 (depends on 3) The system according to claim 3, wherein the estimated air flow is the differential pressure across the associated air filter, when the associated air filter is under full load and the associated air filter is clean and/or new, scaled using the ratio. ### Claim 5 (depends on 1) The system according to claim 1, wherein the periodic cleaning is disabled until the estimated air flow exceeds a threshold. ### Claim 6 (depends on 5) The system according to claim 5, wherein the threshold is the calculated optimal air flow. ### Claim 7 (depends on 1) The system according to claim 1, wherein the processing circuitry is configured to: apply the difference between the estimated air flow and the calculated optimal air flow to a model relating the difference to determine the rate. ### Claim 8 (depends on 7) The system according to claim 7, wherein the model increase the rate as the difference decreases and decrease the rate as the difference increases. ### Claim 9 (depends on 1) The system according to claim 1, wherein the processing circuitry is configured to: periodically clean the associated air filter by controlling a valve of the associated air filter to release a pulse of compressed air at the rate. ### Claim 10 A method for controlling cleaning of an associated air filter apparatus, said method performed by processing circuitry and comprising: estimating air flow across the associated air filter using a pressure sensor disposed at an inlet port of the associated air filter and a pressure sensor disposed at an outlet port of the associated air filter; calculating an optimal air flow across the associated air filter, the optimal air flow resulting in optimal filtering efficiency; and periodically cleaning the associated air filter at a rate determined from the difference between the estimated air flow and the calculated optimal air flow to move air flow towards the optimal air flow. ### Claim 11 (depends on 10) The method according to claim 10, wherein the estimated air flow and the calculated optimal air flow are in terms of differential pressure across the associated air filter. ### Claim 12 (depends on 10) The method according to claim 10, further including: estimating air flow across the associated air filter based on a ratio of: 1) pressure at the inlet port when the associated air filter is under full load and the associated air filter is clean and/or new; and 2) pressure at the inlet port. ### Claim 13 (depends on 12) The method according to claim 12, wherein the estimated air flow is the differential pressure across the associated air filter when the associated air filter is under full load and the associated air filter is clean and/or new scaled using the ratio. ### Claim 14 (depends on 10) The method according to claim 10, wherein the periodic cleaning is disabled until the estimated air flow exceeds a threshold. ### Claim 15 (depends on 14) The method according to claim 14, wherein the threshold is the calculated optimal air flow. ### Claim 16 (depends on 10) The method according to claim 10, further including: applying the difference between the estimated air flow and the calculated optimal air flow to a model relating the difference to the rate to determine the rate. ### Claim 17 (depends on 16) The method according to claim 16, wherein the model increase the rate as the difference decreases and decrease the rate as the difference increases. ### Claim 18 (depends on 10) The method according to claim 10, further including: periodically cleaning the associated air filter by controlling a valve of the associated air filter to release a pulse of compressed air at the rate. ### Claim 19 A self-cleaning air filter apparatus connected to a compressed air source, said apparatus comprising: a filter element configured to filter air flowing through the air filter apparatus; a pulse valve connected to the compressed air source and configured to selectively release a pulse of compressed air into the filter element to clean the filter element; and a control module connected to the pulse valve and configured to: estimate air flow across the air filter apparatus using a pressure sensor disposed at an inlet port of the air filter apparatus and a pressure sensor disposed at an outlet port of the air filter apparatus; calculate an optimal air flow across the air filter apparatus, the optimal air flow resulting in optimal filtering efficiency; and using the pulse valve, periodically release a pulse of compressed air at a rate determined from the difference between the estimated air flow and the calculated optimal air flow to move air flow towards the optimal air flow. ### Claim 20 (depends on 19) The apparatus according to claim 19, wherein the estimated air flow and the calculated optimal air flow are defined in terms of differential pressure across the associated air filter.