Power tool and method of operating an automated drilling operation
AssigneeAtlas Copco Industrial Technique AB
InventorKarl Johan Lars Elsmark
Life of this patent
Estimating the term…
Abstract
An electric power wrench for fastening and loosening joints includes: a main shaft for delivering a torque to a joint, an electric motor that is arranged to selectively drive the main shaft in two opposed rotational directions, a control unit for controlling the drive of the electric motor, and a transmission that connects the electric motor to the main shaft. The control unit has a first drive mode in which it controls the electric motor such that it delivers a continuous torque in a forward direction, and delivers torque pulses in an opposite backward direction, wherein the transmission includes an inherent play and wherein the torque pulses are produced in said play.
Claims15
An electric power wrench for fastening and loosening joints, comprising:
- a main shaft for delivering a torque to a joint,
- an electric motor that is arranged to selectively drive the main shaft in two opposed rotational directions,
- a control unit for controlling the drive of the electric motor, and
- a transmission that connects the electric motor to the main shaft,
- wherein the control unit has a first drive mode in which it is adapted to control the electric motor such that it delivers a continuous torque when driven in a forward direction, and such that it delivers torque pulses en when driven in an opposite backward direction, wherein the transmission includes an inherent play and wherein the torque pulses are produced within said play.
A method of controlling an electric motor in a power wrench for fastening and loosening joints, wherein:
- the power wrench comprises:
- a main shaft for delivering a torque to a joint,
- an electric motor that is arranged to selectively drive the main shaft in two opposed rotational directions,
- a control unit for controlling the drive of the electric motor, and
- a transmission, having an inherent play, that connects the electric motor to the main shaft,
- the electric motor delivers a continuous torque in a forward direction and torque pulses in an opposite backward direction in a first drive mode, and
- the torque pulses are produced within said transmission play.
Dependencies are inferred from the claim text.