Abstract: A light valve has a pair of rotating vanes for controlling the cross section of a light beam passing between the vanes. The vanes rotate on corresponding shafts, each controlled by its own integral motor. Separate feedback control systems produce electrical control signals to each motor for rotating each shaft independently of the other to control the desired phase angles of the vanes. In one embodiment, both motors are permanent magnet direct current servo motors in which the wound armature is an integral part of each shaft. A stationary magnetic field generated by permanent magnets is common to both motors. Power is supplied to each armature by a pair of thin, parallel, flexible, electrically conductive strips extending from an end of each shaft. The conductive strips reduce the torque on the shaft when twisted during operation. In one embodiment, the control system produces a calibrated digital control signal from a PROM representing the desired phase angles of the rotating blades.

Abstract: A header member containing an air chamber is positioned above each pocket of a document sorter, the air chamber having an upwardly directed inlet port and a plurality of downwardly directed outlet ports downstream of the inlet port. An air supply nozzle is positioned below the inlet port to blow air into the air chamber, the air then flowing out of the chamber through the outlet ports. The supply of air into the chamber is interrupted when a document passes between the inlet port and the supply nozzle, and the air flow is resumed when the document passes the inlet port, the air flowing from the outlet ports blowing the document downwardly, out of the path of the succeeding document, and into the pocket of the document sorter.

Abstract: A drive roller and a driven, braked, retard roller are juxtaposedly positioned along the path of documents being transported beyond a document feeding mechanism to provide passage of only one document at a time. The retard roller is carried on an arm which is swingable on a pivot and lightly spring loaded against the drive roller, such arm being placed and positioned at a certain angle rearward of a line extending perpendicular from the document, this angle being larger than the friction angle of document against document, but smaller than the friction angle of document against roller. A single document will pass between the rollers with both rollers rolling at the same speed, whereas when two documents attempt to pass between the rollers at the same time the second document will be retarded by the retard (braked) roller.

Abstract: A plurality of drive rollers, flexibly supported, are positioned along the inside track of a document transport passageway to drive the documents therealong, and a plurality of idler rollers, in opposed relationship to the drive rollers, are positioned along the outside track of the passageway. Each of the drive rollers and the idler rollers is supported from a pivot pin offset from the center of the roller to permit the roller to be canted by reason of gravity and elastic force, and thereby drive the documents in a forwardly and downwardly direction against a fixed edge guide to insure straight and longitudinal travel of the documents at a predetermined level along the passageway.

Abstract: An electro-hydraulic system capable of high speed and precision timing, is disclosed, particularly adapted to the opening and closing of the intake and exhaust valves of an internal combustion engine under computer control. The actuator is powered by pressurized crankcase oil which is discharged on the engine valve stems for lubrication. The system employs hydraulic cushioning to reduce engine valve seating velocity, and recovers energy on the return stroke of the valve to improve efficiency. High speed is achieved by rapid de-energization of electromagnets which hold the fluid control valves closed against the force of the pressure of the hydraulic supply. These electromagnets latch the valves in their most power-efficient mode, that is, with the magnetic circuit gap at or near zero.