US 12,288,544 B2
Power tool having noise reduction features
Ronald J. Hoffman, Iva, SC (US); Scott W. Reed, Anderson, SC (US); and Ashley B. Amick, Jr., Seneca, SC (US)
Assigned to TECHTRONIC CORDLESS GP, Anderson, SC (US)
Filed by TECHTRONIC CORDLESS GP, Anderson, SC (US)
Filed on Sep. 25, 2023, as Appl. No. 18/372,288.
Application 18/372,288 is a continuation of application No. 17/148,114, filed on Jan. 13, 2021, granted, now 11,817,073.
Claims priority of provisional application 62/963,806, filed on Jan. 21, 2020.
Prior Publication US 2024/0013763 A1, Jan. 11, 2024
Int. Cl. G10K 11/162 (2006.01)
CPC G10K 11/162 (2013.01) 18 Claims
OG exemplary drawing
 
1. A blower comprising:
an air inlet;
an axial fan to generate airflow through the blower;
a pre-swirl system comprising a stator disposed between the air inlet and the axial fan, the stator comprising a plurality of vanes angularly offset relative to a longitudinal axis of the airflow to rotationally pre-swirl the airflow upstream of the axial fan; and
a noise cancelling system comprising:
a microphone;
a sound source; and
a controller that controls a second sound emitted from the sound source in response to a first sound received by the microphone.