# US 9,038,923 B2 · Fluid level indicator in an airless fluid sprayer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,038,923 B2 - Document ID: US9038923B2 - Status: Granted - Kind: B2 - Application number: 12/754,209 - Filed: 2010-04-05 - Published: 2011-10-06 - Granted: 2015-05-26 - Earliest claimed: 2010-04-05 - Assignees: Wagner Spray Tech Corporation - Applicants: Wayne D. Robens; Gregory Wayne Parkhurst; James Leo Campbell - Inventors: Wayne D. Robens; Gregory Wayne Parkhurst; James Leo Campbell - Web page: https://patentgrep.com/patent/US9038923B2 ## CPC - B05B 9/0861: {the motor being electric} - B05B 7/2402: {Apparatus to be carried on or by a person, e.g. by hand; Apparatus comprising containers fixed to the discharge device (B05B7/0012 takes precedence)} - B05B 9/0805: {comprising a pressurised or compressible container for liquid or other fluent material (B05B9/085 takes precedence)} - B05B 12/081: {responsive to the weight of a reservoir or container for liquid or other fluent material; responsive to level or volume of liquid or other fluent material in a reservoir or container} - 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) ## Abstract The present disclosure generally relates to systems and devices for spraying fluid materials such as paints, stains, and the like, and more specifically, but not by limitation, to a fluid level indicator for an airless fluid sprayer. In one example, an airless fluid sprayer is provided and includes a fluid container, a controller, and a fluid level indication module implemented by the controller to generate an indication of a level of fluid material in the fluid container. ## Claims ### Claim 1 A paint sprayer comprising: a paint container; a paint pump configured to pump paint from the paint container; a spray nozzle configured to spray paint pressurized by the paint pump; an electric drive mechanism that activates the paint pump in response to application of current pulses; a controller including: a paint level indicator that provides feedback to the user indicative of the paint in the paint container being below a threshold level; a counter that stores a count indicative of current pulses applied to the electric drive mechanism; and a processor that: compares the count from the counter to a current pulse threshold value; and activates the paint level indicator to provide the feedback based on the comparison. ### Claim 2 (depends on 1) The paint sprayer of claim 1, wherein the processor comprises a microprocessor. ### Claim 3 (depends on 1) The paint sprayer of claim 1, wherein the electric drive mechanism comprises a reciprocating electromagnetic actuator and the current pulses are applied by the controller to the electromagnetic actuator. ### Claim 4 (depends on 3) The paint sprayer of claim 3, wherein the controller generates the indication based on at least one of a number of the pulses applied to the electromagnetic actuator and an amplitude of the pulses applied to the electromagnetic actuator. ### Claim 5 (depends on 1) The paint sprayer of claim 1, wherein the threshold value is user-adjustable and indicative of a threshold number of current pulses. ### Claim 6 (depends on 1) The paint sprayer of claim 1, and further comprising a control mechanism configured to be implemented by a user to reset the counter, wherein the threshold value is adjusted in response to the user resetting the counter. ### Claim 7 (depends on 1) The paint sprayer of claim 1, wherein the controller does not require a signal from a fluid level sensor in the paint container to generate the indication. ### Claim 8 (depends on 1) The paint sprayer of claim 1, wherein the controller is configured to: apply a plurality of current pulses to an electromagnetic actuator that drives the paint pump; maintain the counter indicative of the plurality of current pulses applied to the electromagnetic actuator; and generate the indication based on a value of the counter. ### Claim 9 (depends on 8) The paint sprayer of claim 8, wherein the controller s configured to compare the value from the counter to a threshold value. ### Claim 10 (depends on 9) The paint sprayer of claim 9, wherein the counter stores the value indicative of the number of current pulses applied to the electromagnetic actuator. ### Claim 11 (depends on 10) The paint sprayer of claim 10, wherein the value stored in the counter is indicative of an amplitude of each of the number of current pulses applied to the electromagnetic actuator. ### Claim 12 (depends on 1) The paint sprayer of claim 1, wherein the paint sprayer comprises a handheld airless paint sprayer. ### Claim 13 (depends on 12) The paint sprayer of claim 12, wherein the paint container is removably attached to the handheld airless paint sprayer. ### Claim 14 (depends on 1) The paint sprayer of claim 1, and further comprising a temperature sensor configured to provide an indication to a controller indicative of a temperature of the paint sprayer. ### Claim 15 (depends on 1) The paint sprayer of claim 1, wherein the feedback comprises at least one of an audible alarm and a visual alarm. ### Claim 16 (depends on 15) The paint sprayer of claim 15, wherein the feedback comprises an illuminated light on the paint sprayer. ### Claim 17 A paint sprayer comprising: a paint pump configured to pump paint from a paint container; a spray nozzle configured to spray paint pressurized by the paint pump; a user activated control; an electric drive mechanism that activates the paint pump in response to application of current pulses; and a controller that: determines a number of current pulses applied to the electric drive mechanism; compares the number of current pulses to a threshold value that is user-adjustable; generates an indication of a level of paint in the paint container based on the comparison; and adjusts the threshold value in response to a user activated control. ### Claim 18 (depends on 17) The paint sprayer of claim 17, wherein the controller maintains a counter for the number of current pulses, and wherein the user activated control comprises a control that resets the counter. ### Claim 19 (depends on 18) The paint sprayer of claim 18, wherein the adjusted threshold value is based on a value of the counter when the counter is reset. ### Claim 20 (depends on 19) The paint sprayer of claim 19, wherein the controller is configured to: determine a second number of current pulses applied to the electric drive mechanism after the counter is reset; compare the second number of current pulses to the adjusted threshold value; and generate a second indication of a level of paint in the paint container based on the comparison.