Paint sprayer with dynamic pulse width modulation driven motor
AssigneeGraco Minnesota Inc.
InventorTyler J. KRUZEL
Life of this patent
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Abstract
A fluid sprayer includes a housing, a pump, a nozzle, a high voltage direct current (HVDC) brushed electric motor that drives the pump, and a motor controller electrically connected to the motor. The motor controller drives the motor with a high speed pulse width modulated (PWM) drive signal that switches current through the motor on and off. The motor controller varies the PWM signal as a function of a spray setting input and sensed current through the motor.
Claims21
A fluid sprayer comprising:
- a housing;
- a pump connected to the housing;
- a nozzle for spraying fluid delivered under pressure by the pump;
- a direct current brushed electric motor located in the housing and configured to operate the pump;
- and
- a motor controller electrically connected to the motor to drive the motor with a high speed pulse width modulated (PWM) signal that switches current through the motor on and off.
A method of controlling power to a motor of a fluid sprayer, the fluid sprayer comprising a housing, a pump connected to the housing, a nozzle for spraying fluid delivered under pressure by the pump, the motor located within the housing and which operates the pump, a spray setting input, a current feedback circuit, and a motor controller, the method comprising:
- receiving a user selected pressure setting from the spray setting input;
- delivering a high speed pulse width modulated (PWM) signal which switches current through the motor on and off;
- measuring current through the motor with the current feedback circuit;
- and
- modulating a duty cycle of the PWM signal based on the user selected pressure setting and the measured current through the motor.
Dependencies are inferred from the claim text.