초록 ▼

A fluid delivery system includes a pump operably coupleable to a source of fluid. A reciprocating electromagnetic actuator is coupled to the pump and has a coil that when energized causes the actuator to drive the pump. Coil current sensing circuitry is configured to provide an indication of current

A fluid delivery system includes a pump operably coupleable to a source of fluid. A reciprocating electromagnetic actuator is coupled to the pump and has a coil that when energized causes the actuator to drive the pump. Coil current sensing circuitry is configured to provide an indication of current flowing in the coil. A controller is coupled to the coil current sensing circuitry and is configured to calculate a coil drive parameter based upon a plurality of coil current indications from the coil current sensing circuitry. Coil drive circuitry is coupled to the controller and is configured to supply current to the coil based on the coil drive parameter.

대표청구항 ▼

1. An airless paint sprayer comprising: a pump;a reciprocating electromagnetic actuator operably coupled to the pump, the actuator having a coil that when energized causes the actuator to drive the pump;coil current sensing circuitry configured to provide an indication of current flowing in the coil

1. An airless paint sprayer comprising: a pump;a reciprocating electromagnetic actuator operably coupled to the pump, the actuator having a coil that when energized causes the actuator to drive the pump;coil current sensing circuitry configured to provide an indication of current flowing in the coil;coil drive circuitry configured to supply current to the coil; anda controller coupled to the coil current sensing circuitry and the coil drive circuitry to supply current pulses to the coil during a plurality of pulse cycles, each pulse cycle having a pulse on-time in which current is applied to the coil and a pulse off-time, the controller being configured to: set a target pulse on-time threshold;monitor a current pulse applied to the coil during a particular one of the pulse cycles;terminate the monitored current pulse if a duration of the monitored current pulse meets the target pulse on-time threshold; anddetermine whether an amplitude of the monitored current pulse meets an amplitude threshold and, in response: terminate the monitored current pulse;determine the pulse on-time of the monitored current pulse that was terminated;adjust the target pulse on-time threshold based on the determined pulse on-time; andterminate a current pulse applied to the coil during one or more subsequent pulse cycles based on the adjusted target pulse on-time threshold. 2. The airless paint sprayer of claim 1, wherein each of the plurality of pulse cycles has a substantially similar pulse cycle period. 3. The airless paint sprayer of claim 2, wherein the period of each pulse cycle is approximately 8.33 milliseconds. 4. The airless paint sprayer of claim 2, wherein the controller comprises a microprocessor. 5. The airless paint sprayer of claim 1, and further comprising a battery pack operably coupled to the coil through the coil drive circuitry. 6. The airless paint sprayer of claim 1, wherein the reciprocating electromagnetic actuator comprises an armature configured to pivot about a pivot assembly and drive a piston of the pump, and wherein the piston includes a biasing mechanism, and wherein the armature is configured to move the piston in a first direction and the biasing mechanism is configured to move the piston in a second direction, the first and second directions being anti-parallel. 7. A method of operating an airless paint sprayer having an electric drive with an inductive drive coil, the method comprising: setting a target pulse on-time threshold;providing current pulses to the inductive drive coil during a series of pulse cycles, each current pulse having a pulse on-time in which current is applied to the inductive drive coil;for a non-first pulse cycle in the series of pulses cycles, sensing a current pulse in the inductive drive coil during the non-first pulse cycle;determining that the current pulse applied during the non-first pulse cycle satisfies a threshold condition;based on the determination, instantaneously terminating the current pulse by removing current from the inductive drive coil during the non-first pulse cycle;setting a target pulse on-time threshold for one or more subsequent pulse cycles, subsequent to the non-first pulse cycle; andterminating a current pulse during the one or more subsequent pulse cycles based on the target pulse on-time threshold. 8. The method of claim 7, wherein terminating the current pulse during the non-first pulse cycle comprises: determining the pulse on-time for the terminated current pulse; andcalculating a pulse off-time for the non-first pulse cycle based on the determined pulse on-time. 9. The method of claim 7, and further comprising initiating the method in response to a trigger pull on the airless paint sprayer sprayer. 10. The method of claim 7, wherein the method is repeated periodically. 11. A fluid sprayer comprising: a fluid pump;an electric drive operably coupled to the fluid pump, the electric drive having a coil that when energized causes the electric drive to drive the pump to pressurize, fluid;a spray nozzle configured to emit the pressurized fluid in a spray pattern;a coil drive component configured to apply current pulses to the coil during a series of pulse cycles at a particular frequency, each current pulse being applied during a pulse on-time of a corresponding pulse cycle having a first duty cycle;coil current sensing circuitry configured to provide an indication of current flowing in the coil; anda controller configured to receive the indication of current flowing in the coil and adjust a duty cycle of at least one subsequent pulse cycle based on the indication of current flowing in the coil, wherein the at least one subsequent pulse cycle is subsequent to the series of pulse cycles and is applied to the coil at the same particular frequency, wherein the controller is configured to instantaneously terminate the current pulse applied to the coil based on the indication of current flowing in the coil. 12. The fluid sprayer of claim 11, wherein the series of pulse cycles and the at least one subsequent pulse cycle have substantially the same cycle period, and the at least one subsequent pulse cycle has a second duty cycle that is different than the first duty cycle. 13. The fluid sprayer of claim 11, wherein the controller is configured to calculate a coil drive parameter based upon a plurality of coil current indications, each of the plurality of coil current indications corresponds to a different current pulse applied to the coil. 14. The fluid sprayer of claim 12, wherein the at least one subsequent pulse cycle has a pulse off-time that is different than the pulse off-time of the series of pulse cycle having the first duty cycle. 15. The method of claim 7, wherein the one or more subsequent pulse cycles have a cycle period that is substantially similar to the series of pulse cycles, and wherein configuring comprises: adjusting a duty cycle for the one or more subsequent pulse cycles. 16. The method of claim 7, further comprising: sensing an amplitude and a duration of the current pulse applied to the inductive drive coil during the non-first pulse cycle, wherein the threshold condition pertains to at least one of the target pulse on-time threshold, a threshold current amplitude, and a dip and rise in the current pulse. 17. The airless paint sprayer of claim 4, wherein the pulse cycle period of the at least one subsequent pulse cycle is substantially similar to the pulse cycle period of the plurality of pulse cycles. 18. The airless paint sprayer of claim 1, the controller being further configured to, upon termination of the monitored current pulse, calculate the off time for a remaining portion of the particular pulse cycle. 19. The fluid sprayer of claim 11, wherein the fluid sprayer comprises a handheld airless paint sprayer.