Abstract: Article tracking logic apparatus for monitoring plural articles passing through a modular article processing system. An article path actuator activates discrete logical paths for tracking each article within the processing modules. Each logical path includes an article position memory which updatably stores the position of an associated article within an activated path. An article tracking update means is provided within each logical path to cooperate with article position transducers and error detection logic to determine abnormal article transport conditions within an active path. Decode logic is provided within each logical path to provide the control unit for the processing system with the precise path and position therein where an error has occurred.

Abstract: A printed circuit board mounting system uses three pairs of channels 7, 11, 14 to support a board 3 in a rest position, a test position or a repair position, for the maintenance of the board 3 without its removal from the equipment of which it is a part.

Abstract: A keyswitch comprising a housing, a plunger which slides in a channel in the housing, a pair of crossed, opposing cantilever beams which have their fixed ends attached to the housing floor and which with their free ends make springing contact with the plunger, and a pair of electrical contacts each of which is attached to a respective cantilever beam. The keyswitch may also include a cam element to achieve switching and a third contact element to create a bounceless switch.

Abstract: A transistorized master slave flip-flop having a threshold offset generated through circuit size variations. The area of the emitter regions of selected bipolar transistors in the master and slave flip-flops are varied to provide preferred sequencing and thereby avoid untimely changes in state. Adjusting the area of the emitter regions provides the necessary offset without increasing the number of components or circuit crossovers.

Abstract: A control circuitry for operation of a matrix wire printer for impacting a continuously inked rotating platen for printing variable information onto transported documents moving between the printer and the platen. The platen carries a velocity control element for rotative cooperation with a bias roller to initially intercept and decelerate the document to a proper print speed prior to print initiation. Document position is transduced into a plurality of logic signals for commanding the individual actuation of successive columnar prints by the pin printer for printing a preselected message as stored in memory.

Abstract: A DIP socket having preloading and antiwicking features. Each socket contains a plurality of unitary metallic contacts wherein each contact has; a pair of outwardly bowed tails; an antiwicking stem; a U-shaped body with a pair of retention latches on the outward portions of the arms of the U-shaped main body, said main portion of the U-shaped body having a flexural surface; and a pair of arcuately-curved, facing, inwardly-bowed spring biasing members above the U-shaped body. The contacts are inserted into a rectangular, unitary housing having a plurality of contact cavities. Each cavity has a guiding taper and pin aperture, camming faces, a guiding chamfer and a retention ledge. One or more of the interior walls of the cavity tapers inwardly from the lower portion to the upper portion of the cavity. The housing may also include raised standoffs on its lower side.

Abstract: A unitary retention arm or holder for use with a printed circuit card or board. The holder comprises an elongated L-shaped arm of generally rectangular cross section, being wider at its base than at its L-shaped opposite end. The L-shaped end has a narrow channel formed therein for receiving the edge of a printed circuit card, with a guiding ramp or chamfer leading to the channel. A threaded bolt is molded into the base of the holder. The holder is formed from a slightly flexible plastic.In operation, the holder is attached to a printed circuit card frame or cage or other support means with its base bolted near individual card connectors. A printed circuit card having edge connectors is inserted into its appropriate card connector, the card holder is flexed away from its associated printed circuit card, and then the outer edge of the printed circuit card is pressed into the channel formed in the L-shaped end of the holder.

Abstract: A method for interrupting the execution of a keyboard macroinstruction by a central processor to permit execution of non-keyboard macroinstructions when no external data is present in the central processor keyboard buffer. Auxiliary registers are provided mirroring critical registers used by the central processor for processing both keyboard and non-keyboard macroinstructions. The central processor interrogates the keyboard buffer to ascertain entered data. If no entered data is present, a non-keyboard macroinstruction is executed. If entered data is present, it is processed. Values are continuously exchanged between the auxiliary and critical registers to maintain the proper values for executing both keyboard and non-keyboard macroinstructions.

Abstract: A system for interfacing a plurality of stations with a shared device by granting access to the device in the order of requests from the stations. The system elements are serially interconnected for bidirectional communication between the stations and the shared device. Each station employs a register to store a value representing the relative access priority of that station for the shared device. Whenever a station seeks access to the shared device its register is reset to zero and a count-up signal is propagated to all other waiting stations to cause them to increment the values in their registers. When the shared device again becomes available for access the values in the registers are transferred within each station to race counters where they are counted up by a clock until one of the terminals reaches a predetermined maximum count and is granted access to the shared device.

Abstract: In a high speed document printing system a hole mask circuit is provided to compensate for erroneous indications of the entry of additional documents into the system due to the sensing of a discontinuity or aperture within the body of a valid document. The hole mask circuit receives a document present signal from an associated sensor and employs a retriggerable timing means to inhibit the recognition of an additional document unless the sensor has previously signaled the continuous absence of a document for a preselected time interval. The circuit is capable of discriminating between a valid document having apertures of a preselected maximum size, documents having invalidly sized apertures and spacings between successive documents.

Abstract: An adjustable holder for mounting a magnetic head so that it can be adjusted for both lateral and angular deviation with respect to the center line of a recording track. The holder includes a carriage adapted to receive guide pins and a yoke carrying the magnetic head on a leg at one end. The yoke is attached to the carriage by a fastener which permits vertical and rotational displacement. The leg of the yoke includes three equally-spaced openings to receive rotational coupling elements, each of which includes a shank having an enlarged head at one end and a flange with a diametrical groove at the other end. The carriage has three fixed pins received within the grooves of respective coupling elements. The axes of the coupling elements define the corners of one equilateral triangle while the axes of the fixed pins define the corners of a similar but non-congruent equilateral triangle.