Abstract: A time accounting system for accounting for the time a process spends in a ready state, a wait state, or a running state. The system includes a time-of-day clock coupled to a central processing unit for outputting the time-of-day whenever a process changes state. A memory also coupled to the central processing unit stores the contents of a plurality of addressable process control blocks and each process control block includes first, second, and third storage locations for storing indications of the amount of time an associated process has been in the running, ready, and wait states, respectively. The central processor unit accesses the process control blocks and updates the process times stored therein in accordance with control signals generated by decoding a string of microinstructions stored in a control store memory. The time-of-day clock is accessed each time a process enters one of the running, ready, or wait states and each time the execution of a process is completed.

Abstract: An indexing rotary actuator for applying the torque of a rotatable pivot arm to rotate a member between plural index positions. The forward stroke of the pivot arm drives a slider crank linkage through a four bar linkage to unlock the rotatable member and rotate the member to its next index position. On the return stroke of the pivot arm a spring biased locking arm on the rotatable member is interlocked with the actuator to lock the rotatable member in the index position. Interlock switches are provided to indicate when a rotated member is in a valid index position.

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 modular high speed document printing system an apparatus within each printing module for inhibiting printing on a document passing therethrough when a valid print inhibiting code is sensed on the document. The apparatus employs a document lead edge sensor for sensing the presence of a document within the printing module and a print inhibiting code sensor for scanning preselected portions of a document for a print inhibiting code. A timing means is responsively coupled to the lead edge sensor for defining a time interval corresponding to the time interval wherein a valid print inhibiting code may be found. A retriggerable counter is responsively coupled to the print inhibiting code sensor for initiating counting in a memory means upon the sensing of a possible print inhibiting code. Means are provided for determining from the outputs of the counter and the timing mechanism whether a code sensed by the print inhibiting code sensor is a valid print inhibiting code.

Abstract: A buffer storage system having divisible data storage space which is time-shared by a plurality of external data devices and is accessed by at least two independently clocked bidirectional access ports. The storage system is modular and comprises a variable number of fixed-sized buffer cells, each of which may be associatively addressed by any of the access ports. The transfer of data is at a clock rate determined by the particular accessing port; and the transfer is performed serially to achieve variable field length capability and a reduction in hardware. The amount of total storage space can be easily varied by changing the physical number of buffer cells in the buffer system.

Abstract: A method for separating the signal carrying conductors from the ground conductors in a plural conductor flat cable to enable the connection of the ground conductors to a grounding plane and the insertion of the signal conductors into the terminals of a connector block. The method comprises the steps of severing the insulation surrounding the ground and signal conductors in a flat conductor cable, sliding the severed insulation along the conductors away from the main body of the cable, bending the ground conductors at right angles with respect to the flat cable, and sliding the insulation back along the signal conductors until it abuts the main body of the flat cable.

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: A rotable circular disc ribbon for use with a high speed impact printer. The disc ribbon includes a central ink storage chamber enclosing ink saturated porous material. The disc ribbon also includes an outer circumferential film portion positionable between the character dies or dot matrix pins of an impact printer and an image receiving web. Capillary action between ink storage chamber and the film portion of the ribbon provides continual replenishment of the ink in the film portion as it is depleted by impact printing on the web. This replenishment is further aided by centrifugal forces propelling the ink from the storage chamber to the film portion in amounts which are related to the speed of rotation of the ribbon disc.

Abstract: Apparatus is described for use in depositing bank deposit envelopes in a receptacle according to an enforced sequence of actions in a deposit cycle, each action having to take place within specified time periods. The apparatus includes error testing means terminating the deposit cycle at any stage thereof in which an action occurs deviating from the predetermined sequence or not within a time period specified in the sequence. The sequence controller includes a shift register having an output for each stage in the cycle, a logical gate for each stage which gate is enabled by a signal from the shift-register output of the preceding stage, and clocking means responsive to the output signals from the logical gates for clocking the shift-register.

Abstract: A circular shift register memory system comprising L sections each having K circular charge storage shift registers of N bits each for storing blocks of N, K-bit words and accessing the words or blocks thereof in parallel. The L memory sections are refreshed by N-bit clock bursts which are successively and periodically applied to the memory sections by a refresh counter, decoder and gating logic. A read/write decoder decodes memory section addresses and controls the application of N-bit clock bursts to the particular addressed memory sections for access purposes. In a random access mode, word access is facilitated by counters which count the number of read/write or refresh clock pulses for comparison to a word address.

Abstract: A magnetic recording head structure having independent read/write heads located on opposite sides of a flexible recording disk to enable the reading and writing of information on both the upper and lower surfaces of the disk. Each read/write head is supported by corresponding cantilever arms connected to a common head positioning carriage. Each read/write head employs a pressure pad positioned on the opposite side of the flexible recording disk to urge the disk into recording contact with the read/write head associated with the pressure pad. The read/write heads are "D" shaped with the bar portions of the "D" shaped heads located adjacent to each other to insure that the heads do not overlap for any portion of the recording disk. The read/write heads include appropriate coil and magnetic core structures to enable the heads to write information onto the disk, read back previously written information from the disk, and erase information that exists on the disk.

Abstract: A controlled impedance connector for providing a high density controlled impedance interface between a computer backplane and printed circuit (PC) logic card circuitry having signal carrying conductors and a ground surface imbedded in a dielectric medium at selected spacings to achieve a desired characteristic impedance. A common ground surface is provided for a plurality of signal conductors which are in a selected geometrical relationship with the ground surface. Another embodiment of the invention uses a plurality of microstrips embedded in a dielectric medium and dielectrically separated from a common ground surface to achieve the desired characteristic impedance.

Abstract: A printer unit for selectively printing on documents fed between a matrix printer and a rotatable inked platen. The platen is actuably movable between a retracted position and an advanced print position. The document while being printed upon is moved at the same speed as the velocity of the periphery of the rotating platen. The document feed is limited by a feed control roller cooperating with a pressure roller. The feed control roller is coaxial with the rotatable platen and is adapted to move therewith between the retracted position and the print position. A solenoid is provided to move the feed control roller and platen between the two positions. The documents are permitted to pass through the print station unimpeded when the roller platen and feed control roller are retracted.

Abstract: An apparatus for forming solid character charge patterns on a dielectric surface in a non-impact printing system. The apparatus comprises a corona source of ions and a rotatable stencil drum surrounding the corona source to shape the ions generated by the corona source and accelerated therefrom by electrostatic forces into solid patterns of charge. A coaxial stationary shield is provided surrounding the stencil drum to capture the solid patterns of charge. A series of grid covered openings are longitudinally disposed along the shield to form a print station. Means are provided to electrically bias the individual grids covering the openings in the shield at a potential which either blocks the passage or enhances the transmission of patterns of charge through the shield onto an adjacent dielectric surface.

Abstract: A document transport apparatus for serially transporting sheet material over a preselected transport path including an endless belt having a resilient compressible tubular base member and gripping members projecting therefrom. The gripping members are normally closed when the base member is uncompressed. The apparatus further includes pulleys at opposite ends of the transport path, the belt being entrained in the grooves of the pulleys. The grooves are dimensioned to compress the portion of the base member entrained therein, thereby opening the gripping members projecting from the compressed portion of the base member, permitting insertion or removal of a document. The belt grips the document and carries it along with it in the space between the pulleys.

Abstract: A dynamic capacitive memory cell having a storage node formed at the common junction of a fixed access capacitor and two MOS voltage variable capacitors. Data represented in the form of stored charge is written into the storage node through the fixed access capacitor under control of one of the MOS voltage variable capacitors and read out of the memory cell by a sensing device connected between the other voltage variable capacitor and ground. In another memory cell, one of the MOS voltage variable capacitors is replaced by an MOS transistor for preventing excess charge accumulation at the storage node.

Abstract: A circuit for detecting whether current flowing in an external circuit is zero or constant d.c., or is varying in amplitude or, in particular, alternating. A voltage is induced in the detection circuit in response to current flowing in the external circuit, and is compared to a preselected threshold voltage range by a plurality of voltage comparators. The output signal from the comparators is stored in a flip-flop, which generates a signal along a first path if the comparator output indicates that the induced voltage is within the preselected range, thereby indicating zero d.c. or constant d.c. current in the external circuit, or along a second path if the comparator output indicates that the induced voltage is outside the preselected range, thereby indicating varying d.c. or a.c. current in the external circuit.

Abstract: A content addressable memory system for accessing blocks of data stored in circular charge coupled shift registers in response to a tag word presented to a directory unit comprising circular charge coupled shift registers. The memory includes clocking and logic circuitry for providing selective, high speed clocking of blocks and directory unit registers for both read and write operations. Additional logic facilitates masked directory searches at selective clock rates. Automatic synchronization of fast and slow clocked registers is provided by a counter of predetermined count corresponding to the formula N/(1-H) where H is the number of bits per circular register and H equals the ratio of slow to fast shift rates. A use bit register in the directory unit and a bookkeeping loop register in each module further aid in synchronization of the memory operation.

Abstract: A power supply system for use in conjunction with digital systems and particularly adapted to avoid impairment of digital system performance by power supply generated noise. The clock frequency of the digital system is monitored, divided and then applied to control the switching frequency of a D.C. to D.C. power converter. The converter thus switches at a synchronized submultiple of the digital clock frequency such that switching transients are confined to transition times within the digital system.

Abstract: A fixture for interfacing electrical leads with the terminal edges of a printed circuit card, having a frame for supporting the card, a fixed connector for receiving one of the card's terminal edges and a movable connector slidably mounted on the frame and responsive to the operation of an actuating member for mating with the card's second terminal edge while simultaneously forcing mating of the fixed connector and first terminal edge. As mating occurs, resilient fingers mounted in conjunction with the second connector and previously cammed away from the card engage apertures in the card. These fingers serve to extract the card from the fixed connector when the movable connector is actuated away from the fixed connector toward a stop. At the stop, the fingers are cammed out of the apertures, and the progression of the card is halted while the movable connector continues its motion and thereby decouples from the then stationary second terminal edge.