US 12,143,047 B2
Stall protection for a motorized window treatment
Donald F. Hausman, Jr., New Tripoli, PA (US); and Chen Ming Wu, Emmaus, PA (US)
Assigned to Lutron Technology Company LLC, Coopersburg, PA (US)
Filed by Lutron Technology Company LLC, Coopersburg, PA (US)
Filed on Nov. 20, 2023, as Appl. No. 18/514,583.
Application 18/514,583 is a continuation of application No. 18/069,513, filed on Dec. 21, 2022, granted, now 11,863,103.
Application 18/069,513 is a continuation of application No. 17/645,614, filed on Dec. 22, 2021, granted, now 11,558,002, issued on Jan. 17, 2023.
Application 17/645,614 is a continuation of application No. 16/525,650, filed on Jul. 30, 2019, granted, now 11,233,478, issued on Jan. 25, 2022.
Claims priority of provisional application 62/711,981, filed on Jul. 30, 2018.
Prior Publication US 2024/0097598 A1, Mar. 21, 2024
Int. Cl. H02P 29/032 (2016.01); E06B 9/68 (2006.01); E06B 9/70 (2006.01); E06B 9/82 (2006.01); H02P 7/03 (2016.01); H02P 29/024 (2016.01)
CPC H02P 29/032 (2016.02) [E06B 9/70 (2013.01); E06B 9/82 (2013.01); H02P 7/04 (2016.02); H02P 29/024 (2013.01); E06B 2009/6818 (2013.01)] 22 Claims
OG exemplary drawing
 
1. A motor drive unit for driving a motor of a motorized window treatment, the motor drive unit comprising:
a motor drive circuit configured to control power delivered to the motor;
a rotational sensing circuit configured to generate a sensor signal that indicates rotation of the motor, the rotational sensing circuit configured to generate the sensor signal such that the sensor signal periodically alternates between first and second states when the motor is rotating;
a control circuit configured to generate a drive signal for controlling the motor drive circuit to control the power delivered to the motor and an enable signal for enabling and disabling the motor drive circuit, the control circuit configured to detect a stall condition of the motor and to control the enable signal to disable the motor drive circuit and cause the motor drive circuit to stop driving the motor in response to detecting the stall condition; and
a stall prevention circuit comprising a capacitor configured to charge from the drive signal to generate a direct-current (DC) voltage across the capacitor;
wherein the stall prevention circuit configured to:
when the control circuit is generating the drive signal and the motor is rotating, periodically discharge the capacitor in response to the sense signal changing from the first state to the second state, such that the DC voltage across the capacitor does not exceed a reference voltage;
when the control circuit is generating the drive signal and the motor is not rotating, ceasing periodically discharging the capacitor such that the DC voltage across the capacitor exceeds the reference voltage; and
controlling the enable signal to disable the motor drive circuit in response to the DC voltage across the capacitor exceeding the reference voltage.