Abstract: The DC to DC converter includes a coupled inductor having a primary winding and a feedback winding. A drive current regulator circuit receives a variable input voltage from the feedback winding but transmits a constant base drive current to the base terminal of the converter switching transistor. The base drive regulator circuit thereby enables the DC to DC converter to operate at high levels of efficiency over wide ranges of DC input voltages such as twelve to forty-eight volts DC.

Abstract: A variable frequency DC to DC converter generates a pulsed, variable magnitude output voltage where the frequency of the pulsed output voltage varies with changes in the magnitude of the output voltage. An energy storage capacitor is coupled between the converter coupled inductor and strobe flash lamp or other gaseous discharge tube and is periodically discharged through the flash lamp. A variable impedance device in the form of a capacitor is coupled in series with the flow of current from the coupled inductor into the energy storage capacitor to provide a low impedance current flow path when energy is transferred from the coupled inductor into the capacitor and to provide a high impedance current flow path between the converter DC voltage input terminals and the energy storage capacitor when energy is transferred from the capacitor into the strobe flash lamp.

Abstract: The operation of a strobe lighting system is electronically monitored from a remote location to verify proper operation of all of the individual elements of the system. A current sensor is coupled in series with the flow of current between the strobe power supply and the strobe lamp and generates a voltage pulse in response to each flash inducing pulse of current through the strobe lamp. A remote indicator is coupled to the current sensor and generates a humanly perceptible output signal (visual or audible) in response to the voltage pulse from the current sensor. The strobe flash monitor enables a strobe lighting system user to continuously monitor system operation without direct observation of the strobe lamp flashes.

Abstract: The converter delivers current to an intermittently energized load and includes a coupled inductor having a primary winding, a secondary winding and a feedback winding. A switching translator is coupled in series with the primary winding of the inductor and switches between conductive and non-conductive states to control the flow of current through the primary winding. A positive drive circuit provides positive bias voltage to the switching transistor. A current limiting circuit senses the base voltage of the switching transistor to measure the primary winding current, removes the positive bias voltage when the primary winding current reaches a predetermined value, and thereby switches the transistor out of the conductive state into the non-conductive state. A negative drive circuit is coupled between the feedback winding and the base of the switching transistor and supplies a constant negative bias voltage to the transistor base as energy is transferred from the inductor into a load.

Abstract: A vehicle to loading dock releasable locking unit includes a hook for engaging a coupling on the vehicle, a motorized drive system for rotating the hook back and forth between locked and unlocked positions, and a hook position sensor for sensing whether the hook is in the locked, the unlocked or an unsafe position between the locked and unlocked positions. The automatic control system includes a hook position selector for generating lock or unlock signals in response to a hook position command selected by an operator and for storing the selected hook position command. A first actuator control unit energizes the hook actuator to reposition the hook into the locked position in response to the lock signal. A second actuator control unit energizes the hook actuator to reposition the hook into the unlocked position in response to the unlock signal.