Abstract: A power tool includes a housing, a motor supported by the housing, and an output spindle rotatably supported relative to the housing about an axis. The motor is operable to drive the output spindle about the axis. The power tool includes a spindle lock assembly between the motor and the output spindle. The spindle lock assembly is adjustable between an unlocked state in which the output spindle is rotatable relative to the housing about the axis and a locked state in which the output spindle is rotationally fixed relative to the housing. The spindle lock assembly includes a first resilient member, positioned between the housing and the output spindle. The first resilient member is configured to at least partially absorb a torque impulse from the output spindle when rotating in a first direction and when the spindle lock assembly transitions from the unlocked state to the locked state.

Abstract: A clutch can include an input; an output; a centrifugal clutch mechanism that transfers energy from the input to the output, the centrifugal clutch mechanism including: a disk; centrifugal weights movably coupled to the disk; and a central shaft rotatable relative to the disk and extending through the disk, the central shaft comprising drive surfaces, wherein the disk is rotatably coupled to the input, wherein the output is rotatably coupled to the central shaft, wherein the centrifugal weights rotate between a disengaged position in which the centrifugal weights do not interface with drive surfaces and an engaged position in which the centrifugal weights interface with the drive surfaces, and wherein the centrifugal weights are disposed inside the perimeter of the disk when the centrifugal weights are in the engaged position.

Abstract: A power tool includes a housing, a drive mechanism supported within the housing, a spindle operatively coupled to an output of the drive mechanism such that torque from the drive mechanism rotates the spindle about an axis, and a clutch assembly configured to selectively limit torque transfer from the drive mechanism to the spindle. The clutch assembly includes a plurality of rolling elements, a biasing member configured to bias the plurality of rolling elements into engagement with the output of the drive mechanism, and a sleeve movable along the axis to adjust a torque limit of the clutch assembly by varying a preload of the biasing member. The sleeve is made of a high-temperature, engineering thermoplastic.

Abstract: A rotary power tool includes a housing and a drive mechanism disposed within the housing. The drive mechanism includes an electric motor, a transmission operably coupled to the electric motor, a spindle operably coupled to an output of the transmission, the spindle configured to transmit torque generated by the electric motor to a working tool bit, and a clutch disposed between the output of the transmission and the spindle. The clutch includes a plurality of spherical rolling elements configured to engage the output of the transmission, a plurality of cylindrical clutch elements, and at least one biasing member configured to bias the cylindrical clutch elements towards the spherical rolling elements. Each of the cylindrical clutch elements includes a length measured parallel to a rotational axis of the spindle and a diameter, and the diameter is greater than the length.

Abstract: A power tool includes a housing, a motor supported by the housing, and an output spindle rotatably supported relative to the housing about an axis. The motor is operable to drive the output spindle about the axis. The power tool includes a spindle lock assembly between the motor and the output spindle. The spindle lock assembly is adjustable between an unlocked state in which the output spindle is rotatable relative to the housing about the axis and a locked state in which the output spindle is rotationally fixed relative to the housing. The spindle lock assembly includes a first resilient member, positioned between the housing and the output spindle. The first resilient member is configured to at least partially absorb a torque impulse from the output spindle when rotating in a first direction and when the spindle lock assembly transitions from the unlocked state to the locked state.