Clutch assembly for a power tool

A rotary power tool comprising:

• a housing;
• and
• a drive mechanism disposed within the housing, the drive mechanism including
• 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 including
• 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,
• wherein each of the cylindrical clutch elements includes a length measured parallel to a rotational axis of the spindle and a diameter, and wherein the diameter is greater than the length.

A rotary power tool comprising:

• a housing;
• and
• a drive mechanism disposed within the housing, the drive mechanism including
• 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 and configured to selectively transfer torque from the output of the transmission to the spindle, the clutch including
• a plurality of spherical rolling elements configured to engage the output of the transmission, the plurality of spherical rolling elements configured to slip relative to the output of the transmission when the torque from the transmission exceeds a selected torque limit,
• a plurality of puck shaped clutch elements configured to be selectively aligned with the plurality of spherical rolling elements, the puck shaped clutch elements being larger in diameter than length,
• at least one biasing member configured to bias the plurality of puck shaped clutch elements towards the spherical rolling elements,
• an adjustment mechanism configured to vary the selected torque limit,
• and
• a lockout ring rotatable between a clutch configuration, in which the clutch is operable to limit the torque transferred from the output of the transmission to the spindle, and a lock out configuration, in which the clutch does not limit the torque transferred to the spindle.