Abstract: A printer control system uses two microprocessors and a print control for operating a plurality of print hammers in synchronism with a revolving type carrier. One microprocessor is a mechanical control processor, the print hammers are operated by a self timed print control system and the other microprocessor is a print control processor that communicates with a host system for receiving print and control data used by the print control and the mechanical control processor for operating the printer. The mechanical control processor monitors a speed selection device such as an operator panel with speed control keys and operates controls for operating drive means for moving the type carrier at selected speeds. The print control processor supplies speed control data from a diskette to the mechanical control processor for control the type carrier speed.

Abstract: A carburization and heat treatment process of a machine part for obtaining different depths of carburizations in different surfaces of the machine part. The process consists of the steps of; deep carburization of a partly preformed blank of the machine part (FIG. 2A and 2B) to a suitable depth of carbon penetration, machining the partly preformed blank to desired sizes (FIG. 1A and 1B) thereby partly or completely removing the carburization in not preformed dimensions of the blank, shallow carburization of the machined machine part to a desired depth of carbon penetration, and finally heat treating of the machine part.

Abstract: Damping apparatus within an actuator device in which a backstop is supported on one portion of a dual cantilever to match the movement of the impacting actuator to reduce wear and provide positive restoration of initial position, wherein the backstop-supporting cantilever portion is embedded in energy-absorbing elastomeric material that is symmetrically confined to shorten settling time of the actuator and remain unaffected by temperature changes.

Abstract: For compensating for the lateral displacement of the ribbon (4) during the print operation in impact printers with revolving type carriers (9), an inclined pivotable roller (1) is used which is taken along by contacting the moving ribbon. This roller has a pivot (10) with a free end pivotable between two stops (11,12). If there is no lateral ribbon displacement to be compensated for, the pivotable roller is arrested in its respective current position and thus prevented from rotating. In the event of a ribbon displacement (LS), the pivotable roller rotating about its axis exerts a force component (LO) on the ribbon, counteracting the lateral displacement (LS).

Abstract: A positioning system for a line printer uses dc servomotors for driving a forms feed mechanism in increments of one or more line spaces at a time. The system includes a microprocessor and a position counter that counts either 1/4 or 1 degree displacement pulses generated by a motion indicating means including optical transducers and an emitter disk coupled to the motors. The motion indicating means includes an error hold and compensation counter that counts and stores 1/4 degree pulses generated during error movement of the motors relative to a stop position during the uncontrolled state and supplies a corrected 1 degree pulse to the position counter upon start up.

Abstract: Servo control circuit for a DC motor having programmable timers to control the motor energizing period independently for each unit of shaft displacement. The circuit includes timer-gated latches to signal below-speed and above speed conditions and override the timer control period to reestablish the desired velocity.

Abstract: Apparatus for sensing the position of an electrically conductive printing band in which the band moves at varying depths within the gap of an inductor in an inductor-capacitor resonance circuit that is periodically energized to induce eddy currents in the band. The oscillatory ringing resulting from pulsing the tank circuit decays at a rate that varies with the magnitude of the induced eddy current and, hence, the depth of the band in the gap. By counting the number of voltage excursions across the tank circuit resulting from an excitation that exceed a predetermined threshold during decay, the position of the band can be deduced. Corrective positioning may thereafter be undertaken.

Abstract: Circuit for detecting variations in the nominal velocity of a character band and adjusting the hammer firing times to compensate for the variations. This circuit measures deviations in band velocity that are either faster or slower than a nominal velocity during each character emitter pulse and makes an appropriate correction in the subscan times that gate the hammer firing signals. A bidirectional counter is counted up at a high frequency to a value representing the emitter period including the velocity deviation and then counted down after the error determination at a selected frequency that is a preselected fraction of the high frequency. This technique corrects for each character emitter pulse and incorporates a timing proportionality to assure correct hammer impact.

Abstract: A strip assembly for a printing device having an endless type band frictionally driven by drive and idler pulleys between print hammers and a platen comprises a wear strip and wiper strip attached together at a common end. The wiper strip has a wiper portion extending from the point of attachment which terminates in a scraper edge. A retention device mounted in proximity with the drive pulley comprises means connectable to the common end to hold said wear strip under tension and said wiper strip in spring loaded condition with the scraper edge in contact with the drive surface of the drive pulley for cleaning wear strip residue and other deposits from the pulleys and the type band.

Abstract: Apparatus for recording in memory the data of a displayed video frame by storing as data bytes all of the binary data bits from the video data signal appearing as scan lines generated in succession within groups in a frame. The capture of video data occurs within a single regeneration of the raster image. Also recorded in memory for each scan line is a status byte to designate whether the next predetermined number of scan lines are to be omitted to provide spacing between rows of displayed characters.

Abstract: Microprocessor-controlled adapter circuit for real-time controls, in particular for print hammer controls in line printers with revolving type carrier with two asynchronously driven FIFO buffers (FIRST IN, FIRST OUT). The first FIFO buffer contains time values (e.g., firing times for the print hammers) and the second FIFO buffer control information associated with these time values (e.g., print hammer address, control commands for the print hammer). By a request circuit (e.g., counters), the time values are successively read from the first FIFO buffer and fed to a gate circuit for switching the control information, associated with these time values, from the second FIFO buffer for controlling the output values.

Abstract: To reduce the extremely high wear in steel belt printers, a revolving tape is arranged between the revolving steel belt and the platen.

Abstract: A fault protection system for impression devices of a printer detects fault current in the impression devices during non-print operation, checks the impression devices individually to determine the location of the fault and then disconnects the impression devices from the power supply. The fault protection system also includes means for recording the fault location data in a storage means which can be called out for later use in repairing the impression devices.

Abstract: An actuator element having a fixed end and a magnetizable deflection end is releasably held in spring loaded condition at a non-operative position by an electromagnetic operator. In the preferred form, the actuator element is an elastic beam of magnetically permeable material. The operator comprises first and second permanent magnets for generating separate magnetic fields of the same polarity proximate the magnetizable deflection end of the actuator element and a magnetic core combined with the permanent magnets to form at least first and second magnetic holding circuits with the deflection end of the actuator element through a common return path. A winding on the return path of the core when energized generates flux in opposition to the flux from the permanent magnets to release the actuator element for movement to an operative position. Upon de-energization of the winding, the deflection end of the actuator element is retracted and held by the permanent magnets in spring loaded condition.

Abstract: A control system for a band printer uses a correction memory which stores address correction values for resetting the start addresses of the address registers which operate to scan the band image and print line buffers. The correction memory is programmable to store different sets of address correction values when type bands having different size character sets and/or pitch are interchanged.

Abstract: A hammer timing control system for a line printer has a register for storing a digital delay value related to the actual flight time of a controlled print hammer. A delay counter activated by an initiate fire pulse counts timing pulses until the count equals the delay value in the register. A comparator generates a fire signal when the count equals the delay value in the register. The counter continues counting pulses to a second count whereupon the fire signal is terminated. The second count is either decoded or compared with a predetermined quantity in a second register to terminate the fire signal. The counter may also be an up/down counter which counts up to delay and down to terminate the fire signal. Delay values can be stored in an external memory device such as a magnetic disk for transfer to the individual registers for each of the print hammers.

Abstract: A linear solenoid device comprises a cylindrical armature or plunger freely movable within the central opening of a stator which comprises a cylindrical coil wound between a pair of annular end pole members and surrounding one or more intermediate annular pole members. The intermediate pole members are axially spaced and aligned with the end pole members by a bobbin which preferably is injection molded. The armature has plural axially spaced and aligned annular pole members concentrically arranged within the central opening of the single cylindrical coil. The magnetic stator and armature poles take the form of rings which are dimensioned and arranged so that the magnetic flux generated by the coil passes in a series path alternately from the stator to the armature rings and then through a cylindrical magnetic casing which forms a magnetic flux path between the end pole members. The armature includes a support body of non-magnetizable material which may be plastic and can be injection molded.

Abstract: The control system for a line printer includes compensation circuit means for electronically changing the timing of the reference or home pulse to compensate for changes in the speed of the type characters on a continuous type carrier. The compensation circuit includes a storage register, a counter and a comparison circuit for comparing the content of the storage register and the counter. The counter when activated by a reference pulse generated from a reference mark on the moving type carrier counts subscan pulses generated from timing marks moving with the type characters. The storage register, which is programmable, stores different numeric values dependent on the speed of the type carrier representing different numbers of subscan pulses to be counted by the counter means. The comparator circuit compares the numeric value in the register with the count registered in the counting means.

Abstract: Apparatus for stacking a web of continuous prefolded paper forms includes a compacting mechanism having a plurality of elongate rigid compacting finger elements vertically suspended in pairs and freely pivotable from a horizontal rotating crankshaft located above and along one side of a paper stack. The finger elements which have a roughened active surface are vertically reciprocated by the crankshaft so that their active surface slidingly engages the topmost fold or edge of the stack during downward movement but disengages the stack during upward movement.