Abstract: A balanced photoconductor usage control system for an electrophotographic copier/printer machine having a photoconductor containing thereon two page images areas, is employed to solve the problem of excessively high background level due to toner filming. More specifically, the control system includes memory means for retaining a location of a last page image area which was last used to produce a page, and control means jointly responsive to a presence of a full page condition in a page buffer, and to the memory means to effect production of a next page on an alternate page image area.

Abstract: A two-level storage hierarchy for a data processing system is directly addressable by the main processor. The two-level storage includes a high speed, small cache with a relatively slower, much larger main memory. The processor requests data from the cache and when the requested data is not resident in the cache, it is transferred from the main memory to the cache and then to the processor. The data transfer organization maximizes the system throughput and uses a single integrated control to accomplish data transfers.

Abstract: A corona wire, either directly or through an auxiliary element, engages the spiral thread of a screw-like stub member mounted on the housing of a corona charging apparatus to provide a simple, low cost and easily assembled corona wire adjuster. The stub member is mounted on the housing such that it may be rotationally driven much like a screw, but, unlike a screw, will not move into or out of the housing as it is rotated. Rotation of the stub member causes the corona wire to move in a direction parallel to the stub member axis in response to the thread engagement and thereby change its position relative to a photoconductor surface.

Abstract: A fuser roll apparatus in a toner fixing station associated with an electrophotographic or xerographic device for fixing a toner image onto a copy sheet by the application of heat and pressure. The fusing apparatus includes a heated fuser roll and a pair of smaller, spaced backup rolls, each of the backup rolls having a peripheral surface covering of a different elastic modulus from the other. The backup rolls are arranged so as to cooperate with the heated fuser roll to define two fusing nips through which a copy sheet sequentially passes. The downstream roll has the harder peripheral surface covering. As the copy sheet passes through the two nip areas in succession, the downstream backup roll tends to pull against the upstream backup roll. Thus, the copy sheet is tensioned as it passes over the portion of the surface of the heated fuser roll between the two backup rolls.

Abstract: A driver for an electromagnetic device, e.g. a solenoid, is capable of driving the device at a fast cycling rate while dissipating minimal power. In response to an actuating signal, a capacitor connected to a high voltage source supplies a high level current to the device for a short time interval until the capacitor is charged. Thereafter, a resistor connected to a low voltage source, supplies a low level current to the device, thus minimizing power dissipation. In response to the cessation of the actuating signal, a transistor connected in parallel with the capacitor turns on, and acts as a low impedance in parallel with the capacitor, to rapidly discharge the capacitor. Once discharged, the capacitor again may supply high level current to the device when the actuating signal is reapplied.

Abstract: A gas discharge display panel may be used for display purposes despite the presence of open conductors in the panel. Four termination areas, each including a plurality of repair pads are provided, one at each end of each of the two conductor arrays in the panel. One end of each conductor in each array is connected to a respective repair pad in the adjacent termination area. A repair cable having a plurality of conductors runs from the termination area at one end of a conductor array to the termination area at the other end of the array. To repair an open, opposite ends of a respective repair cable conductor are connected to the open conductor's repair pads.By virtue of the connection of the opposite ends of a repair cable conductor to the open conductor's repair pads, both ends of the open conductor are electrically connected. When an open conductor is energized at one end, the entire body of the open conductor is at the same electrical potential despite the presence of the open.

Abstract: A wire matrix printer has a plurality of heads, each consisting of nine wires arranged in a slanting format. The printer can be controlled to print Oriental type characters such as Japanese by loading a wire image map of the characters into a memory. The loading technique loads the memory in a slanted fashion corresponding to the slant of the print heads and reads from the memory in a bit column manner to correspond to the position of the various wires of the multihead print block. The loading and unloading of the wire image memory is controlled by a pair of microprocessors operating respectively on different halves of the memory, such that at any given time, half of the memory is being loaded while the other half is being read from. Thereafter, the memory is switched so that the loaded half is read and the previously read half is cleared and loaded with a new line of information.

Abstract: There is disclosed herein a dot matrix tilting print head assembly in which the print head is rotatably mounted in a frame. A solenoid is provided for rotating the print head a controlled distance so that printing occurs between previously printed dots. A pin extending from the print head is positioned into a larger diameter hole in the frame for controlling the distance to be one half of the center-to-center distance between printed dots. This entails maintaining very low tolerances for the mechanically moving parts. In addition, there is provided support members for allowing the removal of the print head alone from the frame means.

Abstract: There is disclosed herein printer control logic for controlling a matrix printer. The control logic includes an interruptable microprocessor, together with associated memory. Additionally the control logic includes a programmable timer which provides a signal a determined time after being programmed. The control logic responds to print emitter signals manifesting an incremental movement of the print head by interrupting the microprocessor. The microprocessor then programs the timer to provide signals after a programmed delay time to again interrupt the microprocessor. The microprocessor then provides signals causing the operation of the print elements on print head.

Abstract: A print mechanism for a wire printer has a robust single-turn closed-loop transformer secondary winding as the moving part for driving a print wire into and out of a print position. Each secondary winding threads a transformer core on which is wound a multi-turn primary winding. A stack of such secondary windings, arranged with print wires in a closely spaced print row across the stack is supported in a static magnetic field produced by a magnetic assembly. Energization of a selected primary winding induces a large current flow in its associated secondary winding which reacts with the static magnetic field to drive the associated print wire into the print position. In one embodiment, the stack of secondary windings are all mounted on a single pivot and each secondary winding swings about the pivot as a whole upon energization of its associated primary winding.

Abstract: A video data display terminal includes a video display, eg., a CRT, and a character buffer for storing character bytes representing characters to be displayed on the screen of the video display device. The terminal further includes microprocessing means for receiving data from a keyboard device connected thereto or alternately from a host processor for entry into the character buffer. The microprocessing means are further adapted to define one or more partitions on the screen of the video display device. Data integrity within these partitions is maintained by assigning margin attribute bytes to the margin of each partition. Refresh hardware including refresh logic control means, a line buffer, a character generator and a serializer is provided to write data within the character buffer to the video display screen.

Abstract: This invention provides an improved method and apparatus for manufacturing magnetic recording media; specifically, that which is to be used in the manufacture of flexible, magnetic recording disks. The process provides a sequence of disorienting magnetic fields in different directions and of diminishing strengths to form a magnetic media in which the magnetic particles are essentially disoriented and the media is, thereby, devoid of modulated signal envelopes.

Abstract: A clamp for holding a flexible sheet on a rotary carrier tightens the grip on, and pulls, the sheet upon rotation of the carrier, as a result of centrifugal forces generated on two weights attached to two cooperating arms within the clamp. The magnitude of the grip-tightening force is dependent upon the mass of a grip-tightening weight attached to the clamp. The magnitude of the sheet-pulling force is dependent upon the mass of a sheet-pulling weight attached to the clamp. The clamp faces are mounted for concurrent movement along the periphery of the carrier to prevent tearing or other damage to the sheet when it is pulled as the carrier is rotated.

Abstract: Disclosed is a spatially coherent semiconductor injection laser array. The system comprises a plural element laser diode array placed symmetrical in respect to an optical axis. An external resonating cavity formed of spherical lenses and plane mirrors is disposed about the array with its axis of symmetry coincident with the optical axis. A spatial filter in the Fourier plane of the laser diode array selects the TEM.sub.00 mode generated from each of the elements in the array. In operation, the system generates spatially coherent radiation from each of the elements of the array. The radiations are coherently coupled between all of the elements to provide a high optical power output in a spatially coherent beam.

Abstract: A set-up store is added to an intelligent data processing terminal for storage of terminal characterizing information therein. Terminal characterizing information includes a representation of installed terminal features and a representation of selected terminal options. The information is changeable by the operator to indicate new installed features or different selectable options.A system of interlocks safeguards against improper operator actions, as follows: An interlock prevents the entry of inaccurate terminal characterizing information. Another interlock disables normal terminal operation if terminal characterization information is not present in the set-up store. A security lock prevents unauthorized entry of terminal-characterizing information. An interlock disables operation of language-unique keyboard keys until a keyboard language has been entered. Another interlock prevents the selection of terminal options unless the installed terminal features are present in the set-up store.

Abstract: Binary information signals which are to be transmitted are combined with a pseudo-random signal wave form such as a pseudo-random sequence of binary bits. Each binary message element, whether a binary "1" or a binary "0", alters successive portions of the pseudo-random binary sequence to thereby create a modified pseudo-random binary bit sequence, successive portions of which represent the binary information. The successive portions of the modified pseudo-random binary sequence are converted to an analog quantity which will be similarly varying in a pseudo-random manner.

Abstract: An object of the invention is to provide a flexible disc having a frusto-conical recording surface. The disc is bistable allowing access to both sides, and is well suited for data storage in computer and data processing systems. It may be used either singularly or collectively in disc packs.

Abstract: This invention provides an improved method and apparatus for manufacturing magnetic recording media; specifically, that which is to be used in the manufacture of flexible, magnetic recording disks. The process provides a sequence of disorienting magnetic fields in different directions and of diminishing strengths to form a magnetic media in which the magnetic particles are essentially disoriented and the media is, thereby, devoid of modulated signal envelopes.

Abstract: A data transmission system which includes stations connected in a closed loop configuration with interface capabilities at each station to connect to an external data processor. Through this configuration simultaneous transmission of data among processors connected to stations on the loop can be carried out by transmission of data around the loop between particular stations. Data is transmitted from a first processor to its individual station connected to the loop. This first station formats the data received from the first processor into frames of multi-bit configuration which are transmitted around the loop to a second station which is connected to a second processor. Data received by the second station is stored and transmitted to the second processor. During the time that this transmission from the first processor to the second processor is being carried out a transmission between other processors connected to stations on the loop can also be carried out.