Milwaukee Electric Tool Corporation

Zachary J Evans

Timothy J Bartlett

Jacob R McDonald

Taylor Crabb

Bryan C Kendall

Jacob R Schaddel

Nicholas E Holstine

Dominick S Ropella

William Booth Howarth

Braking a power tool motor based on a phase voltage of the motor. The power tool includes a motor and a power source providing operating power to the motor. A power switching network is between the power source and the motor to drive the motor. An actuator is operable to provide an input. An electronic controller is connected to the actuator and the power switching network. The electronic controller is configured to receive an indication related to initiating braking of the motor, control the power switching network to allow the motor to coast, monitor a phase voltage of the motor, determine whether the phase voltage of the motor is equal to or less than a phase voltage threshold, and control, in response to the phase voltage of the motor being equal to or less than the phase voltage threshold, the power switching network to brake the motor.

Voltage-based braking methodology for a power tool

An impact power tool including a housing, a motor supported by the housing, a spindle coupled to the motor for receiving torque from the motor to cause the spindle to rotate, and a reciprocating impact mechanism operable to create a variable pressure air spring within the spindle. The impact mechanism includes a striker received within the spindle that reciprocates along a reciprocation axis in response to the variable pressure air spring, a piston that reciprocates along the reciprocation axis to induce the variable pressure air spring, and a crankshaft configured to convert continuous rotational motion from the motor to reciprocating linear movement of the piston. The crankshaft defines a crank axis perpendicular to the reciprocation axis, and the motor defines a motor axis that is parallel with the reciprocation axis. A center of gravity of the impact power tool is positioned between the motor axis and the reciprocation axis.

Impact power tool

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Waukesha, WI, United States of America

Zachary J Evans