Power tool
AssigneeBlack & Decker Inc.
InventorTim Heimrich
Life of this patent
Estimating the term…
Abstract
A power tool comprises a housing and an electric motor disposed in the housing. A rotary output is driven by the motor. Electronic sensor configured to sense operating parameters of the power tool includes a voltage sensor arranged to detect the voltage across the electric motor, a current sensor arranged to detect the current through the tool, and a speed sensor arranged to detect the angular velocity ω of the output spindle. Electronic control apparatus is configured to determine from the operating parameter output signals the torque M of the rotary output and control the angular velocity of the rotary output in response to the calculation of the torque of said rotary output.
Claims15
A power tool comprising:
- a housing;
- an electric motor disposed in the housing;
- a rotary output driven by said electric motor;
- an electronic sensor configured to sense operating parameters of the power tool including the voltage across the electric motor, the current drawn by the power tool and the angular velocity of the rotary output and provide the parameter output signals derived from said sensed operating parameters;
- and
- an electronic control apparatus configured to determine a torque of said rotary output as a function of the voltage across the electric motor, the current drawn by the power tool, the angular velocity of the rotary output, and a tool efficiency, and control the angular velocity of the rotary output in response to the torque of said rotary output.
An electronic control system for a power tool, the system comprising:
- electronic sensor configured to sense operating parameters of a power tool in use, wherein said power tool comprises an electric motor and a rotary output driven by said electric motor, wherein said operating parameters include:
- the voltage across the electric motor, the current drawn by the power tool, and the angular velocity of the rotary output, and wherein said electronic sensor is configured to provide the parameter output signals derived from said sensed operating parameters;
- and
- an electronic control apparatus configured to determine a torque of said rotary output as a function of the voltage across the electric motor, the current drawn by the power tool, the angular velocity of the rotary output, and a tool efficiency, and control the angular velocity of the rotary output in response to the torque of said rotary output.
Dependencies are inferred from the claim text.