# US 8,740,013 B2 · Variable flow air flow controller > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,740,013 B2 - Document ID: US8740013B2 - Status: Granted - Kind: B2 - Application number: 12/060,529 - Filed: 2008-04-01 - Published: 2009-10-01 - Granted: 2014-06-03 - Earliest claimed: 2008-04-01 - Assignees: PFP Control Technologies, LLC - Applicants: Michael D. Elberson - Inventors: Michael D. Elberson - Web page: https://patentgrep.com/patent/US8740013B2 ## CPC - B05B 7/2491: {characterised by the means for producing or supplying the atomising fluid, e.g. air hoses, air pumps, gas containers, compressors, fans, ventilators, their drives} - B05B 12/087: {Flow or presssure regulators, i.e. non-electric unitary devices comprising a sensing element, e.g. a piston or a membrane, and a controlling element, e.g. a valve} - G05D 7/0635: {by action on throttling means (G05D7/0688, G05D7/0694 take precedence)} - Y10T 137/7736: Consistency responsive - B05B: SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES (spray-mixers with nozzles B01F25/72; processes for applying liquids or other fluent materials to surfaces by spraying B05D) - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A system for controlling the operation of pneumatic tools includes a controller for controlling the delivery of compressed air to the tool. The controller includes a first flow path that is associated with operation of the pneumatic tool at a first flow rate and a second flow path that is associated with operation of the pneumatic tool at a second flow rate. The controller is configured to automatically configure the system for operation of the pneumatic tool via a flow of air from one of the first flow path or the second flow path. In painting environments, such a system enhances control of the operation of the pump in accommodating a generally stable pump reciprocation rate as fluid viscosities change. ## Claims ### Claim 1 A method for controlling the delivery of compressed air to a tool, the method comprising the steps of: (a) receiving compressed air from a source; (b) determining a compressed air flow rate; (c) allowing the compressed air to flow through a first flow path at a selected rate sufficient to maintain a selected operating pressure when the determined compressed air flow rate is equal to or less than an air flow rate set with an air flow control valve associated with pumping a paint material having a first viscosity with a pump; and (d) automatically reducing the compressed air flow rate communicated to the pump, independent of a static and dynamic nature of the compressed air flow, by directing the compressed air to the pump via a second adjustable flow path, to maintain a preset air flow rate a pressure below the selected operating pressure associated with the first flow path when the determined compressed air flow rate associated with pumping a material having a second viscosity that is lower than the first viscosity of the paint material through the pump exceeds the selected flow rate to maintain operation of the pump at similar reciprocation rates for fluids having different viscosities. ### Claim 2 (depends on 1) The method of claim 1 wherein step (c) includes receiving an activation signal from a tool. ### Claim 3 A system for controlling operation of a pneumatic tool that is powered by compressed air, the system comprising: an inlet for being connected to a source of compressed air; an outlet for communicating an air flow to a pump of a paint delivery system; at least two flow paths between the inlet and the outlet; and an air flow controller constructed to 1) allow flow along a first flow path via operation of a valve when a flow rate at the outlet approximates a desired flow rate as determined by a pressure regulator and a flow meter based on a viscosity of a first fluid passed through the pump and 2) allow flow along a second flow path when the flow rate at the outlet exceeds a threshold associated with the desired flow rate as determined by the pressure regulator and the flow meter and base on a viscosity of a second fluid passed through the pump that has a different viscosity than the first fluid to maintain a desired reciprocation rate of the pump during operation of the pump to move fluids having different viscosities and as a function of the viscosity of fluid delivered by the pump and independent of a static or dynamic nature of the air flow to the pump. ### Claim 4 (depends on 3) The system of claim 3 wherein the first flow path and the second flow path are associated with operation of the fluid pump at a desired pressure and a desired flow rate for the first fluid and the second fluid, respectively. ### Claim 5 (depends on 4) The system of claim 4 wherein the air flow controller is configured to maintain a relatively consistent reciprocation rate when the pump is pumping a paint solution and a fluid having a viscosity that is lower than a viscosity of the paint solution independent of user interaction with the system. ### Claim 6 (depends on 3) The system of claim 3 wherein the regulator is self-relieving. ### Claim 7 (depends on 3) The system of claim 3 wherein the air flow controller automatically switches the air flow between the first flow path to the second flow. ### Claim 8 (depends on 3) The system of claim 3 wherein the threshold is further defined as one of a preset flow rate or a preset pressure. ### Claim 9 (depends on 3) The system of claim 3 wherein the second flow path maintains a flow rate at a variable preset pressure. ### Claim 10 A pneumatic system comprising: a tool powered by a flow of compressed air; an air flow control valve for providing a desired air flow rate that is to be communicated to the tool powered by the flow of compressed air such that the tool operates at a first cycle rate; and a controller connected to the air flow control valve and disposed upstream of a pressure based flow meter and configured to: 1) allow the air flow to the tool at the desired flow rate along a first flow path associated with the airflow control valve when the air flow is not more than the desired flow rate based on a viscosity of a fluid moved by the tool to achieve the first cycle rate; and 2) allow the air flow to the tool at another air flow rate associated with a second flow path automatically in response to changes in viscosity of the fluid moved by the tool if the air flow rate exceeds the desired air flow rate to maintain operation of the tool proximate the first cycle rate and wherein the desired air flow rate and the another air flow rate associated with the first and second flow paths are allowed to flow to the tool independent of a static and dynamic nature of the air flow. ### Claim 11 (depends on 10) The pneumatic system of claim 10 further comprising an air flow meter that is connected to the controller for detecting the air flow delivered to the tool. ### Claim 12 (depends on 10) The pneumatic system of claim 10 wherein the tool is a pump of a paint spay system and the desired air flow rate is associated with a viscosity of a paint solution and the another air flow rate is associated with a viscosity of another fluid. ### Claim 13 (depends on 10) The pneumatic system of claim 10 wherein the controller is configured to automatically alter the air flow to maintain a pump reciprocation rate that is the same for fluids having different viscosities. ### Claim 14 (depends on 13) The pneumatic system of claim 13 wherein the controller includes a first fluid path for establishing the desired air flow rate and a second fluid path associated with providing one of the desired air flow rate and the another air flow rate. ### Claim 15 (depends on 10) The pneumatic system of claim 10 wherein the desired air flow rate is determined by a user's selection of a desired operating pressure. ### Claim 16 (depends on 15) The pneumatic system of claim 15 wherein the desired operating pressure is provided via a self-relieving pressure regulator.