Abstract: A single pass, multi-color electrophotographic printing machine architecture uses a vertically oriented photoconductive belt. Transfer of the toner powder images occur at the lowermost portion of the photoconductive belt. The photoconductive belt is elliptically shaped, having a major and a minor axis. N image recording stations are positioned adjacent an exterior surface of the photoconductive belt on one side of the major axis thereof. N-1 image recording stations are positioned adjacent the exterior surface of the photoconductive belt on the other side of the major axis thereof. The image recording stations record electrostatic latent images on the photoconductive belt. This architecture optimizes image registration while minimizing the overall height of the printing machine.

Abstract: An apparatus for advancing a sheet. The apparatus includes a transport which has the sheet releasably secured thereto in one mode of operation, and, in another mode of operation reduces the frictional force between the sheet and the transport to facilitate relative movement therebetween. A controller, in communication with the transport, selects the mode of operation of the transport.

Abstract: High resolution character generator for producing rows of characters to be scanned on a display medium. Input data defining characters to be printed in ordered rows of text is sorted to provide specifications for the characters which being on each successive scan line. These specifications are stored initially in an input buffer, and specifications for characters which have been partially printed in a previous scan line are stored in an active character buffer. For each scan line, the character specifications are read first from the active character buffer and then from the input buffer until an end of line specifier is reached. For each character specification received, a font memory containing data defining the characters is cycled. The data from the font memory is decoded and presented to the display medium on a line by line basis.

Abstract: Apparatus for segmenting a buffer memory into two-dimensional sectors such buffer memory having stored herein, in scan-by-scan format, bits representing the image of a document. The sectors comprise sections of adjacent scan lines arranged in a two dimensional array. Included in the apparatus is an address generating means which provides the address arrays for such sectors during the segmenting sequence and an encoding means which inspects the data in each segment. In the instances where all of the data in one sector represents background image a single bit code is transmitted. In all other instances the sector data is transmitted in its entirety. The same address generating and encoding means can be utilized in the receiving mode to reconstruct the code into corresponding data arrays to thus provide an image.

Abstract: A hammer protection circuit automatically disconnects a power supply from a hammer actuating coil in order to inhibit current flow through the coil when such current flow is either greater than a predetermined level or present for greater than a predetermined time period. The circuit comprises charging means coupled to the coil for charging up to a voltage level proportional to the level and duration of the current flow through the coil, comparator means coupled to the charging means for comparing the voltage level with a reference voltage and for generating an output signal when the voltage level bears a predetermined relationship toward the reference voltage, and means coupled to the comparator means and to the power supply and responsive to the output signal for disconnecting the power supply from the coil.

Abstract: Apparatus for enabling communications between two or more data processing stations comprising a communication cable arranged in branched segments including taps distributed thereover. Tied to each tap is a transceiver which on the other side connects to an associated interface stage. Each transceiver includes, in addition to the usual transmitter and receiver sections, a gate which compares the data from the interface stage with the data on the cable and indicates whether such are equal. Should such be unequal, an interference between the transceiver and the cable is indicated, disabling the associated transmitter section. Each interface stage tied to such transceiver also includes an input and an output buffer on the other end thereof interfacing with a using device, such input and output buffers storing both the incoming and outgoing data.

Abstract: A phase-sensitive transducer apparatus comprises first and second relatively movable members, the first relatively movable member having a plurality of windings and the second relatively movable member having a winding. Means are included for applying a first input signal to one of the windings of the first relatively movable member and a second input signal to another of the windings of the first relatively movable member, an output signal being induced on the winding of the second relatively movable member. The first and second input signals are sinusoidal in nature of substantially identical frequency and peak amplitude and are phase-displaced by a predetermined amount, and the output signal is substantially constant in peak amplitude and variable in phase during relative movement of the first and second relatively movable members.

Abstract: A serial printer comprises a carriage, a print member rotatably mounted to the carriage and including a plurality of character elements, a drive coupled to the print member for rotating the print member to a desired rotational position, a device coupled to the print member for generating a plurality of periodic position signals each indicative of the rotational movement of the print member, and a device for storing a count indicative of the actual rotational position of the print member, the device for storing including a device responsive to an increment pulse for incrementing the count by one and a device responsive to a decrement pulse for decrementing the count by one.

Abstract: In a computer peripheral device having a controllable element and control means coupled to the controllable element and operative in response to a power supply voltage of a predetermined level for controlling the controllable element, an improved power supply means coupled to the control means for supplying said power supply voltage to the control means. The improved power supply means comprises a motor capable of being driven at a predetermined rate of speed, means coupled to the motor and responsive to the motor being driven at the predetermined rate of speed for generating the power supply voltage, and means coupled to the means for generating for supplying the power supply voltage to the control means.

Abstract: A matrix print head comprises stylus guide means; a plurality of electromagnetic structures coupled to the guide means, each of the electromagnetic structures including a pole piece; a plurality of armatures disposed radially about the guide means, each of the armatures being associated with one of the electromagnetic structures to form an electromagnetic actuator for transferring electromechanical energy to a stylus, and each of the armatures having an inner end and an outer end projecting outwardly of the associated pole piece; a plurality of styli respectively associated with the plurality of armatures, each stylus being carried by the guide means and having an armature engaging end for engaging the inner end of the associated armature and a printing end for impacting a record medium when the stylus is propelled through the guide means by energization of the associated electromagnetic actuator; and an improved armature retainer coupled to the guide means for maintaining each armature in engagement with its

Abstract: A linear actuator for selectively moving a carriage relative to a support frame along a predefined linear path.

Abstract: A head assembly for magnetic recorders includes a mounting bracket designed for increased rigidity. Releasably attached to the mounting bracket are two head carriages, each having affixed thereon a magnetic recording and reproducing head. The heads are positioned such that as the mounting bracket moves radially with respect to two recording discs, each head is individually precisely radially positionable with respect to any recording track defined on its respective disc.

Abstract: A carriage assembly for transporting a print member along a predetermined path adjacent a support member comprises a first carriage section adapted to be mounted adjacent the support member for movement along the predetermined path, apparatus for mounting a print member to the first carriage section for movement between first and second positions relative to the support member, and apparatus coupled to the mounting apparatus for retaining a print member mounted to the frame in each of its first and second positions. The retaining apparatus includes a biasing member for biasing the print member in a direction opposite its second position when at its first position and in a direction opposite its first position when at its second position. The biasing member preferably includes an over-center tensioned spring coupled between the first carriage section and the mounting apparatus.

Abstract: A phase-sensitive transducer apparatus comprises first and second relatively movable members wherein the first relatively movable member has a plurality of windings and the second relatively movable member has a winding. Means are included for applying a first input signal to one of the windings of the first relatively movable member and a second input signal to another of the windings of the first relative movable member. An output signal is induced on the winding of the second relatively movable member. The first and second input signals are sinusoidal in nature of substantially identical frequency and peak amplitude and are phase-displaced by a predetermined amount, and the output signal is substantially constant in peak amplitude and variable in phase during relative movement of the first and second relatively movable members.

Abstract: Record material feed apparatus for use with a printing machine of the type including a platen, means for rotating the platen about its axis, at least one roller, a lever capable of manual movement between first and second positions, and means coupled between the lever and the roller for maintaining the roller in engagement with the platen when the lever is in its first position and for maintaining the roller spaced a predetermined distance from the platen when the lever is in its second position.

Abstract: A hammer assembly comprising a housing having opposing open ends and an internal passage extending between the open ends. A hammer element is positioned in the housing for reciprocal movement in the passage between first and second positions. The hammer element has an opening formed therein in which a biasing member is positioned. When enabled, the biasing member is capable of biasing the hammer element in a desired direction relative to the first and second positions. Means are also included for enabling the biasing member when the hammer element is in at least its first position. The housing is desirably fabricated of a self-lubricating material with the area of the opening at one of its ends substantially larger than the cross-sectional area of the hammer element, taken along a plane perpendicular to the axis of motion of the hammer element at such one end in order for air to be freely vented from the passage during reciprocal movement of the hammer assembly.

Abstract: A serial printer comprises a carriage, a print member rotatably mounted to the carriage, drive means coupled to the print member for rotating the print member in a desired direction and at a desired speed, and control apparatus coupled to the drive means for generating a control signal to control the direction and speed of rotation of the print member.

Abstract: A serial printer comprises a carriage, a print member rotatably mounted to the carriage and including a plurality of character elements of a predetermined font style, drive means coupled to the print member for rotating the print member to a desired rotational position in order to place a selected character element at a printing position adjacent a record medium to be printed upon, print hammer means mounted to the carriage and capable when enabled of impacting the character element located at such printing position with a desired level of force, and hammer control apparatus coupled to the print hammer means for enabling the print hammer means when the selected character element has been rotated to the desired rotational position.

Abstract: In a serial printer comprising a carriage movable along a predetermined path, a print member rotatably mounted to the carriage and including a plurality of character elements, first drive means coupled to the print member for rotating the print member to a desired rotational position, second drive means coupled to the carriage for moving the carriage to a desired position along the path, and control apparatus coupled to the first drive means for controlling the direction and speed of rotation of the print member and coupled to the second drive means for controlling the direction and speed of movement of the carriage, the control apparatus comprising first means for receiving and storing a first signal indicative of the desired rotational position of the print member, second means for receiving and storing a second signal indicative of the desired linear position of the carriage, means coupled to the first and second means for receiving and storing for generating a third signal if the first signal was received

Abstract: A pin wheel feeding device includes a housing capable of being rotated about an axis. A plurality of substantially identical pins are disposed within the housing in respective alignment with a plurality of openings. Each pin includes a pair of opposing guide members. A cam member disposed within the housing is capable of being fixed in position relative to the housing. The cam member has a track formed thereon with which each of the pins is engaged with the pair of guide members thereof being located on either side of the track. The width of the track at first, second and third segments thereof is substantially coextensive with the locus of points traced by the closest adjacent points on the pair of guide members of each pin during movement of the pins along the first, second and third segments of the track.