Patent ID: 11872680
Assignee: BLACK & DECKER, INC.
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 9:
10. An impact power tool comprising:
a housing;
a motor disposed in the housing and having a motor output shaft;
a transmission having an input member rotatably drivable by rotation of the motor output shaft and a transmission output shaft;
a rotary impact assembly including a cam shaft removably coupled to the transmission output shaft, a hammer coupled to the cam shaft and able to move axially and rotatably relative to the cam shaft; an anvil rotatable about the axis; and a spring biasing the hammer toward the anvil;
a tool output shaft partially or fully received in the housing and rotatable by rotation of the anvil; and
a coupler removably coupling the cam shaft to the transmission output shaft,
wherein when torque on the tool output shaft is at or below a first threshold, the transmission output shaft, the cam shaft, the hammer, and the anvil rotate together to transmit torque to the tool output shaft without impacts;
wherein when torque on the tool output shaft is above the first threshold, and the hammer moves axially and rotationally along the cam shaft toward and away from the anvil to apply intermittent rotary impacts to the anvil and the tool output shaft, and
wherein when torque on the tool output shaft is above a second threshold greater than the first threshold, the coupler decouples the transmission output shaft from the cam shaft, interrupting torque transmission to the tool output shaft.