| 摘要 |
A speed controller operates a DC-powered fastener drive assembly to efficiently drive fasteners from a DC power supply (22), thereby achieving a fully portable hand tool. In particular, the speed controller accelerates a flywheel (28) with a DC motor to a target speed appropriate for the type of fastener and user selection. Thereafter, the speed controller causes the kinetic energy from the flywheel (28) to be imparted to a linearly moving fastener driver. The speed controller is responsive to the rotational speed of the flywheel (28) to ensure a consistent depth of drive and to actuate a clutch for an appropriate amount of time to couple the flywheel (28) to the fastener driver. Thereby, consistent drives are achievement across a range of operating conditions (e.g., battery state of charge, type of fastener, mechanical tolerances and wear, motor performance, etc.). |
