Abstract: This invention secures an electrical plug by inserting a locking pin through a hole in the prong(s) of a male plug or through a hole in a female plug and through a corresponding hole in the male or female receptacle that secures the device plugged into the receptacle. The locking pin is secured by a latching system or locking mechanism that limits access to those not authorized. This invention may be used in conjunction with access-control devices that control access to users of appliances such as video game systems, TVs, computers and the like.

Abstract: An apparatus is provided for modifying a belt conveyor for enabling use of varying belt widths. The apparatus includes a pair of first mounting feet having slots and coupled by a cross member, wherein the first mounting feet are coupled to the cross member enabling the slots to mate with holes disposed on the frame, the apparatus further has second mounting feet having slots and adapted to couple to a first upper idler and a first lower idler, the apparatus further having supports coupled to opposite ends of the cross member, wherein a first end of the supports is coupled to the cross member and a second end is coupled to the second mounting feet. The apparatus is further characterized in that the cross member has a selectable length such that a second upper idler having a width greater than the first upper idler and a second lower idler having a width greater than the first lower idler can be coupled to the conveyor frame.

Abstract: A voltage controlled flyback converter used as a battery charging circuit avoids the power dissipation of the more conventional series-type regulator-type charging circuits but cannot be readily utilized because of the high gain in the feedback loop due to the battery voltage, which causes instabilities therein when it is operated in a continuous current mode.These instabilities are avoided in a flyback converter used for battery charging by using current control techniques to control current on the primary side of the converter during high-rate battery charging. During low-rate charging, normal voltage feedback from an output current sensing resistor is used as long as the converter operates in a discontinuous mode.

Abstract: A power failure detector for an off-line switcher provides an indication of power failure to a microprocessor load to permit an orderly shutdown without loss of data. The failure detector includes a voltage storage device shunting a secondary winding of a converter power transformer prior to the isolating diode. When its voltage drops below a preset threshold, the microprocessor load is notified that a shutdown action is to be taken.

Abstract: An uninterruptible power supply utilizes a controlled ferroresonant regulator to derive a regulated DC voltage from a primary AC source. A reserve source of DC power is coupled to the output through a DC voltage regulator which is activated when the DC output voltage of the power supply drops below a predetermined threshold.