Patent ID: 11911887
Assignee: INGERSOLL-RAND INDUSTRIAL U.S., INC.
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 11:
12. An impact tool comprising:
a swinging weight impact mechanism comprising a hammer frame supporting a hammer that rotates about a first axis, the hammer pivotably coupled to the hammer frame such that the hammer pivots about a second axis, the second axis having an orientation different from the first axis, and an anvil configured to rotate about the first axis when impacted by the hammer;
an electric motor comprising a rotor that is coupled to the swinging weight impact mechanism, the electric motor being configured to drive rotation of the hammer about the first axis in a first direction; and
a control circuit that supplies a current to the electric motor and limits the current supplied to the electric motor, the control circuit including a modulation circuit and a current measurement circuit that measures each successive modulation cycle and disables the current to the electric motor for the remainder of the modulation cycle when the current exceeds a specified threshold for the electric motor;
wherein rotation of the rotor in the first direction rotates the hammer in the first direction, and wherein when the hammer stops rotating in the first direction the rotor is concurrently stopped from rotating in the first direction.