Screwdriver

A screwdriver, comprising:

• a motor,
• a first rotating member that receives rotating torque of the motor,
• a second rotating member that is adapted to rotate by receiving the rotating torque of the first rotating member,
• a tool that performs a screw tightening operation by receiving the rotating torque via the first rotating member and the second rotating member,
• a torque transmission spring that is closely wound around the first rotating member and the second rotating member when the motor drivingly rotates the first rotating member in a predetermined rotating direction, so that the torque transmission spring transmits the rotating torque of the motor from the first rotating member to the second rotating member, and
• means for releasing the torque transmission by releasing the close winding of the torque transmission spring around at least one of the first rotating member and the second rotating member by means of a movement in the axial direction of the first rotating member or the second rotating member in response to the screw-tightening torque, so as to release the transmission of the rotating torque of the motor from the first rotating member to the second rotating member.

A screwdriver, comprising:

• a motor,
• a first spindle that rotates together with the motor and receives a rotating torque of the motor,
• a second spindle that is adapted to rotate around the same longitudinal axis as the first spindle by receiving the rotating torque of the first spindle,
• a driver bit that performs a screw tightening operation by receiving the rotating torque via the first spindle and the second spindle,
• a torque transmission spring that is closely wound around the first spindle and the second spindle when the motor drivingly rotates the first spindle in a predetermined rotating direction, so that the torque transmission spring transmits the rotating torque of the motor from the first spindle to the second spindle, and
• a torque transmission releasing device that moves in the axial direction of the first spindle or the second spindle in response to the screw-tightening torque, wherein the torque transmission device engages with the torque transmission spring so as to prevent the torque transmission spring from being closely wound in the rotational direction of the first spindle, so that the torque transmission releasing device releases the close winding of the torque transmission spring around at least one of the first spindle and the second spindle to release the transmission of the rotating torque of the motor from the first spindle to the second spindle.

A screwdriver, comprising:

• a motor,
• a first spindle that rotates together with the motor and receives a rotating torque of the motor,
• a second spindle that is adapted to rotate by receiving the rotating torque of the first spindle,
• a driver bit that performs a screw tightening operation by receiving the rotating torque via the first spindle and the second spindle,
• a torque transmission spring that is closely wound around the first spindle and the second spindle when the motor drivingly rotates the first spindle in a predetermined rotating direction, so that the torque transmission spring transmits the rotating torque of the motor from the first spindle to the second spindle,
• a third spindle that is disposed adjacent to the second spindle and in the vicinity of the tool, and
• a clutch member that connects the second spindle to the third spindle, the clutch member being adapted to move toward the first spindle in the axial direction in response to the screw-tightening torque, wherein the close winding of the torque transmission spring around the first spindle is performed or released in response to the axial movement of the clutch member.

A screwdriver, comprising:

• a motor,
• a first spindle that rotates together with the motor and receives a rotating torque of the motor,
• a second spindle that is adapted to rotate by receiving the rotating torque of the first spindle,
• a driver bit that performs a screw tightening operation by receiving the rotating torque via the first spindle and the second spindle,
• a torque transmission spring that is closely wound around the first spindle and the second spindle when the motor drivingly rotates the first spindle in a predetermined rotating direction, so that the torque transmission spring transmits the rotating torque of the motor from the first spindle to the second spindle,
• a third spindle that is disposed adjacent to the second spindle and in the vicinity of the tool, and
• a clutch member that connects the second spindle to the third spindle, wherein the clutch member includes an engagement member that extends toward the first spindle, the clutch member being urged away from the first spindle by a spring, the clutch member being adapted and arranged to move toward the first spindle so as to oppose to the biasing force of the spring when the screw-tightening torque exceeds a predetermined torque, such that the engagement member engages the torque transmission spring so as to release the close winding of the torque transmission spring around the first spindle.

A screwdriver, comprising:

• a motor,
• a first spindle that rotates together with the motor and receives a rotating torque of the motor,
• a second spindle that is adapted to rotate by receiving the rotating torque of the first spindle,
• a driver bit that performs a screw tightening operation by receiving the rotating torque via the first spindle and the second spindle,
• a torque transmission spring that is closely wound around the first spindle and the second spindle when the motor drivingly rotates the first spindle in a predetermined rotating direction, so that the torque transmission spring transmits the rotating torque of the motor from the first spindle to the second spindle,
• a torque transmission releasing device that moves in the axial direction of the first spindle or the second spindle in response to the screw-tightening torque, wherein the torque transmission device engages with the torque transmission spring so as to prevent the torque transmission spring from being closely wound in the rotational direction of the first spindle, so that the torque transmission releasing device releases the close winding of the torque transmission spring around at least one of the first spindle and the second spindle to release the transmission of the rotating torque of the motor from the first spindle to the second spindle, and
• a first torque transmission path and a second torque transmission path, wherein the rotating torque of the motor is transmitted from the first spindle to the tool via the torque transmission spring and the second spindle through the first torque transmission path, and when the motor is rotated in a reverse direction so that the torque transmission by the torque transmission spring is released, the torque of the motor rotating in the reverse direction is transmitted from the first spindle to the tool via a one-way clutch through the second torque transmission path.