Power tool, drive assembly, and method of operating the same

A power tool comprising:

• a housing and a motor supported by the housing and including a motor shaft;
• a spindle supported by the housing for rotation about an axis;
• and
• a drive assembly provided between the spindle and the motor shaft such that the spindle is drivingly connectable to the motor shaft to drive a tool element, the drive assembly including:
• a first clutch assembly having an engaged configuration, in which the first clutch assembly transfers a drive force from the motor shaft to the spindle, and a disengaged configuration, in which the first clutch assembly prevents the transfer of the drive force from the motor shaft to the spindle, the first clutch assembly being movable from the engaged configuration toward the disengaged configuration when a torque exerted on the spindle exceeds a torque limit;
• a second clutch assembly having an engaged configuration, in which the second clutch assembly transmits the drive force from the motor shaft to the spindle, and a disengaged configuration, in which the second clutch assembly prevents the transmission of the drive force from the motor shaft to the spindle, the second clutch assembly being movable from the disengaged configuration toward the engaged configuration when the tool element engages a workpiece, wherein the first clutch assembly includes a drive member having a plurality of outwardly extending lugs, a cage having a first cage member and a second cage member, and a clutch member supported in the cage between the first cage member and the second cage member and being selectively engageable with the lugs of the drive member to transfer the drive force from the motor shaft to the spindle.

A drive assembly for a power tool, the power tool including a housing, a motor supported by the housing and having a motor shaft, and a spindle supported by the housing for rotation about an axis, the drive assembly being provided between the spindle and the motor shaft such that the spindle is drivingly connectable to the motor shaft to drive a tool element, the drive assembly comprising:

• a drive member supported in the housing;
• a clutch member supported in the housing and being selectively engageable with the drive member to transfer a drive force from the motor shaft to the spindle when a torque exerted on the spindle is less than or equal to a torque limit and being movable away from the drive member to prevent the transfer of the drive force from the motor shaft to the spindle when the torque exerted on the spindle exceeds the torque limit;
• a first clutch plate secured to the spindle for movement with the spindle relative to the housing;
• and
• a second clutch plate supported in the housing and being engageable with the first clutch plate to transmit the drive force from the motor shaft to the spindle when the tool element engages a workpiece, wherein the drive member includes a plurality of outwardly extending lugs, wherein the clutch member is movable along the drive member and is selectively engageable with the plurality of lugs to transfer the drive force from the motor shaft to the spindle, wherein at least one of the plurality of lugs has a helicoid ramp, and wherein the clutch member is selectively engageable with the one of the plurality of lugs along a line to distribute a contact force along the line.

A power tool comprising:

• a housing and a motor supported by the housing and including a motor shaft;
• a spindle supported by the housing for rotation about an axis;
• and
• a drive assembly provided between the spindle and the motor shaft such that the spindle is drivingly connectable to the motor shaft to drive a tool element, the drive assembly including:
• a first clutch assembly having an engaged configuration, in which the first clutch assembly transfers a drive force from the motor shaft to the spindle, and a disengaged configuration, in which the first clutch assembly prevents the transfer of the drive force from the motor shaft to the spindle, the first clutch assembly being movable from the engaged configuration toward the disengaged configuration when a torque exerted on the spindle exceeds a torque limit;
• a second clutch assembly having an engaged configuration, in which the second clutch assembly transmits the drive force from the motor shaft to the spindle, and a disengaged configuration, in which the second clutch assembly prevents the transmission of the drive force from the motor shaft to the spindle, the second clutch assembly being movable from the disengaged configuration toward the engaged configuration when the tool element engages a workpiece, wherein the first clutch assembly includes a drive member including a first gear portion formed of a first material and a second gear portion formed of a second material, the first material and the second material being different, and wherein the first gear portion defines a recess, and wherein the second gear portion includes an outwardly extending protrusion engageable in the recess to selectively drivingly connect the first gear portion and the second gear portion.