Abstract: Flexible disk record storage apparatus has a chordally perturbed backing plate for inducing a dynamic stiffness in a flexible recording disk rotating immediately adjacent the plate. A head radially movably disposed between the chordal perturbations provides reliable recording and playback. A web portion of the backing plate has a predetermined flatness circumscribing a transducing location for enhancing recording and playback quality.

Abstract: A self-ventilating flexible disk pack receives operating air through a plenum chamber which communicates with the atmosphere through a flow controller. The flow controller has primary and secondary flow passages through which the flow of air is controlled by primary and secondary valves. The primary valve is used to control the creation and termination of an access opening between preselected disks. Upon closing the primary valve the flow of air into the disk pack is blocked and a high vacuum is created which allows a preselected partial split to rapidly open into a full access opening. After the primary valve is closed, a secondary valve member moves to a position in which it is responsive to the pressure within the plenum chamber for restricting and regulating the flow of air so as to maintain a bistable condition maintaining the access opening.

Abstract: Copy machine having provisions for separately addressing and independently exercising individual machine components for maintenance purposes. There are also provisions for addressing sensory components individually and for providing a visual indication of the state of the addressed element so that its proper operation can be verified. In addition to operability indications, the address of the individual machine component being exercised or the sensory component being tested can be displayed.

Abstract: An asynchronous validity checking system and method is disclosed for monitoring a plurality of clock signals carried on separate electrical conductors to assure continuing transitions of each clock signal. A master clock is utilized to produce a plurality of phase-related clock signals on the separate electrical conductors, and the transitions of the clock signals are sensed on each electrical conductor adjacent to the distribution point to a controlled unit to assure that all clock signals are continuously operational. The validity checking system includes a locking synchronizer having a plurality of flip-flops each of which receives a different one of the clock signals and a timing signal from a timing oscillator that is independent of, and asynchronous with respect to, the clock signals from the master oscillator with the clock signals being locked into the flip-flops on the rising leading edges of the pulses of the timing signal.

Abstract: A record disk cartridge has a single internal shutter for opening and closing a head access port adjacent a spindle access member in one wall. A further aperture allows the shutter to be actuated to an open position as the cartridge is moved into a playing position. The shutter also brakes the disk against movement when the cartridge apertures are closed. A magnetic coupling enables rotation of the disk inside the cartridge.

Abstract: A stabilizing backing plate for a rotating flexible record disk has a bearing surface with a smooth finish to prevent disk wear. A plurality of depressions in the backing plate trap air to prevent the flexible disk from adhering to the backing plate during start-up.

Abstract: Utilization of production equipment with diverse throughput rates is optimized by a central random access article storage apparatus disposed centrally of peripherally positioned production equipment. Computer controls enable fully automatic sequencing of production flow. The storage apparatus provide transient storage and article queuing during intermediate successive production steps. The computer control enables automatic article tracking for quality control as well as diagnosis of automatic production equipment problems.

Abstract: A copy production machine having a document feed and a collator controls collator operation for optimum performance in accordance with the status of the original document feed. The collator has a construction such that collation of a moving vane in a first relative direction with respect to a set of collator bins provides more reliable collation operation for enhancing throughput. When an original document is in a position to be copied upon the ending of a current copy production run, collation occurs in both directions of relative motion, whereas in the absence of such original document in the document feed position, collation only occurs in the preferred direction. In other aspects of the invention, whenever copies from multiple images are simultaneously being processed by the copy production machine, collation occurs in both directions of collation, whereas when copies bear images of a single image then collation only occurs in the preferred direction.

Abstract: A copy production machine, such as a transfer electrographic copier, picks copy sheets for receiving images during a transfer operation. On rare occasions a sheet may not be successfully picked. Instead of turning the machine off and requiring manual intervention for a restart, the machine automatically retrys to repick the sheet of paper a predetermined number of times. If during such retry the pick is successful, then the copy production resumes automatically; if not, the machine is turned off after the predetermined number of cycles. During each machine cycle having an unsuccessful pick, protective actions are taken to insure that toner does not contaminate the machine and certain other actions do not provide a fire hazard. All retries are logged for maintenance assistance.

Abstract: A plurality of status reporting units are connected respectively to a plurality of shift registers. The shift registers receive and store status signals from the status reporting units. Each of the shift registers include an OR circuit for combining the signals from all of the stages of the respective shift registers. An output of the OR circuit is connected to the input of one stage of a shift register other than the shift register supplying signals thereto. The arrangement is such that the one stage in the respective shift registers indicate the status of one or more error status reporting units. A status analyzing unit receives signals from the various shift registers for analyzing error patterns of the status reporting units in response to receiving a signal that at least one of the status reporting units has error status to report.

Abstract: Location of multiple symbols in error is enhanced by using affine polynomial-based apparatus and methods. An algebraic trace function 0 (vector) provides a test for whether or not the location polynomial has roots in the field of interest. The selected roots then combine with previously calculated error-indicating syndromes to indicate symbols in error. Informational states developed for error location are employed to generate error patterns.

Abstract: A multi-mode document reproduction machine (copier) includes automatic reselection, activated when a time-out timer times out, which reselects machine parameters to a dominant copy mode. A dominant mode is that machine mode used in the most number of copy jobs, irrespective of the number of copies made in any of the modes. An intermediate machine state inhibits the time-out timer. Copies in an interim storage unit and a copy jam are two examples that generate an intermediate machine state. Removal of copies or the jam allows the timer to time out.

Abstract: The surface of a magnetic disk (23) is divided into servo sectors (S.sub.1) and data sectors (S.sub.2). A selectively positionable magnetic head (24) effects, in predetermined time intervals controlled by clock signals of a clock sensor (26), the transfer of servo and data signals. The servo signals sensed in the servo sectors are used for the track following control of the magnetic head.The servo markings (Ma) recorded in the servo sectors (S.sub.1) are arranged, with twice the width (2d) of the data tracks in radial distances of one respective track width (d), one beside the other in a row along a disk radius. In each servo sector at least three rows (A, B, C) of servo markings (Ma) are provided. The servo markings are arranged in track direction one behind the other in such a manner that between each of the rows (A, B, C) a distance (g) is formed, and that each servo marking of one row overlaps a servo marking of the following row by one track width (d).

Abstract: A hardware counter counts high rate, lower significant bits. A carry-borrow circuit responsive to the higher order bit position of the hardware counter includes cancel means responsive to successively received carry and borrow signals to cancel previously generated carries or borrows. Memory means in the carry-borrow circuit memorize the generation of the carry or borrow by the hardware counter. A programmed microprocessor, or the like, periodically senses the status of the carry-borrow circuit for transferring signal contents thereof to a software controlled count field. The arrangement permits high speed counting without interrupting the microprocessor and not imposing rate constraints on program execution of the microprocessor.

Abstract: A programmable controller includes a random access memory for storing signals relating to a plurality of programs executable in the controller. A portion of the memory addressing is zoned for enabling one or more programs to have exclusive access to that zone. The addressability of input/output registers, diagnostic registers and selected other units of common interest to all such programs are addressable in each of the plurality of zones as if such registers were uniquely assigned to such respective memory zones.

Abstract: Each data record portion on a record member includes preamble signals for synchronizing recording apparatus with respect to data signals recorded in juxtaposition to the preamble signals. A plurality of beginning of data indicators are interleaved in the synchronizing signals for providing a plurality of independent but coacting beginning of data location pointers. Enhanced apparatus includes means responsive to any one of the location pointers to ensure a reliable start of data indication.

Abstract: A Bernoulli disk storage apparatus includes an elongated slot or groove having a substantial radial elongated portion for movably receiving a transducer. On either side of the groove are air bearing means which induce a pull down force on the record storage disk as it passes over the groove. By varying selected parameters, the medium-to-transducer spacing is held substantially constant throughout the radial extent of a desired recording area. Further, flutter usually associated with a Bernoulli disk at its outer radial portion is eliminated.

Abstract: Method and apparatus for assembling a flexible record disk member to a non-flexible center support ring and substantially simultaneously recording servo signals on the flexible disks concentrically with respect to the support ring whereby the recorded servo signals are precisely coaxial to the non-flexible ring support.

Abstract: An improved component feed mechanism allows a component support table to move simultaneously with the component feed mechanism. The table has a plurality of guides for urging guiding component holding cartridges toward a work station. The table is movable transverse to the cartridge lengths. A friction block guide disposed above said table has a block movable parallel to said cartridge feed direction. A feed lever is pivoted on said block; means sense pivoted positions of said feed lever; and means selectively pivot said feed lever between cartridge engaging and retracted positions. The table moves transversely only when said feed lever is in a retracted position enabling concurrent motions of the feed lever and the table for reducing setup time of the machine.

Abstract: Error correcting apparatus is provided for correcting plural channels in error in a parallel channel information system. The information is encoded in a cross-channel direction as well as along the channel length. The encoded message after storage or transmission is decoded in the cross-channel direction and error correction provided in the in-channel direction in a given number of indicated channels. Orthogonally symmetrical redundancy enhances error correction while tending to minimize hardware. Plural independent codes interact to correct the plural channels in error. The error correcting capabilities of the codes may be matched, no limitation thereto intended.