Abstract: A gas spring-powered fastener driver includes a cylinder, a moveable piston positioned within the cylinder, a driver blade attached to the piston and movable therewith between a ready position and a driven position, a lifter to move the driver blade from the driven position to the ready position, and a transmission including an output shaft operatively coupled to the lifter to provide torque to the lifter. The fastener driver also includes an input to provide torque to the transmission and a clutch positioned downstream of the input and operably coupled to the output shaft to limit an amount of torque transferred to the output shaft and the lifter. In response to an application of a reaction torque to the output shaft above a predetermined threshold, torque from the input is diverted from the output shaft via the clutch.

Abstract: A gas spring-powered fastener driver includes a cylinder, a moveable piston positioned within the cylinder, a driver blade attached to the piston and movable therewith between a ready position and a driven position, a lifter to move the driver blade from the driven position to the ready position, and a transmission including an output shaft operatively coupled to the lifter to provide torque to the lifter. The fastener driver also includes an input to provide torque to the transmission and a clutch positioned downstream of the input and operably coupled to the output shaft to limit an amount of torque transferred to the output shaft and the lifter. In response to an application of a reaction torque to the output shaft above a predetermined threshold, torque from the input is diverted from the output shaft via the clutch.

Abstract: An optical power conversion circuit converts an optical energy signal from an optical source, such as a laser diode, to a regulated D.C. electrical voltage using a single photodetector. A buck-boost circuit uses electrical current from the photodetector in response to the optical energy signal to store energy in an inductor during one polarity of a control signal, and transfers the energy from the inductor to an output capacitor during the other polarity of the control signal. The duty cycle of the control signal determines the regulated D.C. electrical voltage. A switch drive circuit generates the control signal as a pulse width modulated signal from the regulated D.C. electrical voltage and a reference voltage. The control signal is A.C. coupled to a pair of FET switches in the buck-boost circuit to alternately energize and charge the inductor and capacitor respectively.