Abstract: A small-sized and light weight printer which can suitably be incorporated in a desk-top calculator or the like. The printer has a simplified mechanisms for driving of a printing head, a paper feed and a printing control, and can operate stably with a reduced power consumption.

Abstract: An apparatus for generating pulses for both character and individual "dot" strobing, as for example, in matrix printers. The apparatus includes a first stationary synchronization track and a cooperating first movable synchronization track (to move with the matrix printer) for generating the start of character pulses and a second stationary synchronization track and a second cooperating second movable synchronization track (to move with the matrix printer) for generating individual "dot" pulses of a character to produce vertically aligned characters in a bi-directional printer. The first synchronization tracks are designed to produce pulses having narrow rise and fall slopes for accurate character location and the second synchronization tracks are designed to produce pulses having gradual rise and fall slopes to provide for adjustment of the individual "dot" pulses for bi-directional printing.

Abstract: The intermittent movement of the printer's carriage and "daisy"-type print wheel is controlled by a relatively simple, reliable digital control system. The difference between the desired velocity and the actual velocity of each member is measured digitally. This difference constitutes an error signal which is used to retrieve stored values of acceleration or deceleration corresponding to various values of the error signal. These values are used to develop a corresponding electrical signal which is used to accelerate or decelerate the member to reach the desired velocity. A relatively simple circuit is provided for reliably returning the carriage or print wheel to a desired position after overshooting the position, despite a relatively large amount of overshoot. Simple, low-power-consumption holding or drive circuits utilizing pulsed voltages are provided for the stepping motors used for ribbon feed and line feed, and for the solenoids used for ribbon shift, print wheel shift and print hammer energization.

Abstract: The aesthetic characteristics of adjacent characters are used to enhance the quality of output in a proportional spacing printer and to provide right margin justification for composing. Spacing between characters is determined on the basis of the character being printed and the preceding character already printed on the page. An intercharacter displacement memory contains a list of ideal spacing for all combinations of characters to be printed. As each character is typed, it and the previously stored preceding character address the intercharacter displacement memory. The output of the intercharacter displacement memory is the ideal value of escapement for this combination of characters and font style. The printer positions the print head prior to printing the next character, rather than positioning the print head after the previous character is printed.

Abstract: A portable electro-mechanical printer has a platen (1) over which electro-sensitive paper is advanced, relative to a print head (6) having a few row of selectively energizable needles (8) which is movable by an electric motor transmission (18,19,21,24) parallel to the platen in a scanning direction transverse the row of needles. A timing disc (25) is driven by the drive transmission, the disc being subdivided into sectors and cooperating with two relatively displaced photocells (26,27) which produce two periodic signals upon rotation of the disc, these signals being utilized to provide clock pulses controlling successive energizations of the print head needles as the latter is scanned across the paper.

Abstract: A wire printer comprises a platen which guides a record medium, a carriage supported for reciprocable movement parallel to the platen, and a print head assembly carried by the carriage and including a plurality of print wires. The head assembly includes a plurality of print wires. The head assembly includes a plurality of solenoids, each of which is connected with one end of an associated print wire, the other end of which is disposed adjacent to the platen with a small clearance therebetween. The other end of each print wire is provided with a portion which is aligned with each other on a common vertical plane. The print head assembly is pivotally connected with the carriage and is guided to undergo a composite motion including an angular and a radial motion such that as the carriage is moved, a given point on the extension of the linear portion of the print wire moves along an imaginary centerline which passes through the center of stroke of the carriage and which is at right angles to the platen.

Abstract: A serial impact printer of the type utilizing a dot matrix print head is specifically adaptable for use as a calculator or adding machine and is characterized by utilizing a common drive source to advance the print head across the paper, advance the paper between printing operations, and selectively advance the print ribbon between the ribbon supply spool and takeup spool. An improved paper-advancing means has been devised which operates in close correlation with the print head drive member to provide a relatively high speed, simplified and inexpensive printer unit; and the ribbon supply spools are so constructed and arranged as to be interchangeable and to permit direct drive through a spool-engaging member on the print head whereby to advance the ribbon in direct response to print head travel.

Abstract: A serial printer for printing information on a record material is disclosed. The printer includes a frame and a platen mounted on the frame for rotation about its axis, the platen capable of supporting and advancing record material through the printer. A carriage assembly is also included and has a printing member supported thereon, the carriage assembly being supported for movement along a printing path adjacent the platen. Further, a motor is mounted on the frame and means are included for converting the rotary motion of the motor to movement of the carriage assembly along the printing path, the converting means including a cable mounted at either end to the frame. Additionally, means are included for maintaining a substantially constant tension on the cable, the tensioning means including means coupled to an end of the cable for automatically taking up slack in the cable caused by stretching or wear of the cable.

Abstract: In a printer having a print head assemblage longitudinally moving along a path parallel to a record medium, a portion of the print head assemblage is controlled to strike the record medium at a desired point by measuring the time required for sonic pulses generated in a rod at the position of the print head assemblage to arrive at a sensor, such time being a function of the distance from the print head assemblage to the sensor. A representation of this time is compared against a similar representation of a time associated with the position of the desired point and upon equality the portion of the print head assemblage is driven toward the record medium.

Abstract: By utilizing as the driving elements for paper positioning and printing head positioning two solenoids, only, with appropriate electrical and mechanical timing control apparatus to assure synchronization of printing and related functions a low cost, portable, low weight, low-power-consumption teletypewriter can be realized.

Abstract: An electronic control circuit is designed for use with a high speed printer having a character generator which is coupled to a print head. The print head is laterally displaced along a print line by a stepper motor and forms characters from a plurality of columns of dots as the print head moves. The electronic control circuit includes an encoder which is coupled to the shaft of the stepper motor to generate count up pulses when the stepper motor displaces the print head in a first direction and count down pulses when the stepper motor displaces the print head in a second direction. The count up and count down pulses permit the control circuit to continuously define the present print head position. A random access memory receives printable characters during a load cycle and reads out printable characters to the character generator during a print cycle.

Abstract: A printer for printing characters on paper supported adjacent a path along which a print head can be traversed. Two servo-motors are mounted adjacent the path and each connected to the head by a toothed belt. Control means connects the servo-motors in one of two modes: in the first, one servo-motor is energized to pull the head on a printing traverse while the other servo-motor is connected as a dynamic brake; and in the other, the other servo-motor is energized to pull the head on a fly-back traverse while the other servo-motor idles. To stop the head either in a printing traverse or at the end of a fly-back traverse, the mode of connection of the control means is reversed.

Abstract: A high-speed printer in which the carriage carrying a print wheel is coupled to a servo controlled driving motor having intermittent motion. The motor drives a helically grooved pulley, which has attached to it left and right cable segments. The other ends of the cable segments are attached to the movable carriage. A cable preload spring and friction pulley snubber combination maintains cable tension relatively constant. The snubber provides a tight cable system during normal carriage acceleration and deceleration. The preload spring allows for tension correction when the cable suffers from long-term stretching due to constructional stretching, that is, the normal tendency of wound cables to stretch due to seating of individual wires in the strand.

Abstract: A carriage guide for supporting a typing element carrier and composed of two guide rails extending parallel to a printing abutment, and pairs of guide rollers mounted on intersecting axes and connected with the typing element carrier for centering the typing element carrier at at least one of the guide rails, is further provided with first and second roller carriers carrying the guide rollers at sides thereof extending parallel to the rails, the roller carriers being disposed to intersect one another and the second roller carrier being provided with a slide edge, elements defining a common joint extending between, and parallel to, the guide rails and via which the carriers bear against one another, a tensioning spring element acting between the roller carriers, a receiving element carried by the first roller carrier at one of its sides parallel to the rails for establishing an articulated connection with the typing element carrier, and a supporting spring element cooperating with the slide edge for effecting

Abstract: A carriage supporting a single type element is couplable either to the upper run or the lower run of a looped cable drive system for left or right or right to left letter feeding movement under control of an escapement pawl carrier associated with a unidirectional control rack and driven by the upper run of the cable drive system.

Abstract: A rotary encoder is coupled to the drive for a printing head to detect and encode movement of the drive and produce signals therefrom which are used to control the direction and positioning of the printing head. A rotating disc-like wheel in the encoder has a plurality of peripheral window openings which act in conjunction with a light source and detector to produce a signal train from which the movement and instantaneous location of the printing head is determined.

Abstract: A drive member in a printer is radially oriented and linearly positioned in the fastening thereof on a shaft at one of a plurality of selected positions. The shaft has a flat portion which receives a hub of the drive member, the hub conforming in shape with the shaft and having a tongue portion thereof fitting along the flat portion of the shaft with the tongue portion being flexibly supported and having a lip engageable with grooves or slots in and across the flat portion of the shaft.

Abstract: A platen gap adjuster for a printer utilizes a shaft along which the print head carriage slides during printing of each line. The shaft is eccentrically mounted by means of unitary, offset spindles the common axis of which is parallel to but spaced from the shaft axis. By rotating the shaft about the common spindle axis, the carriage and print head will be moved transversely of the shaft, thereby adjusting the gap between the print head and platen without impairing the longitudinal sliding motion of the carriage.

Abstract: A printer head is mounted on a carriage which is driven to travel in the row direction at a predetermined constant speed. A pulse generation device is provided for developing a pulse signal in response to the travel of the carriage in order to determine print width. A detection device develops a detection signal when the carriage reaches the first print position to initiate printing of the first character. The detection signal is applied to a counter which counts a time interval from a time at which the last pulse is developed from the pulse generation device to a time at which the detection signal is developed. The following character printing is effected each time the pulse generation device develops a predetermined number of pulses indicative of one character width or print pitch and the time interval determined by the counter has passed from the time at which the last pulse of the predetermined number is developed.

Abstract: A printer including a print head adapted for reciprocal displacement across a print tape for effecting printing on the tape in at least one direction of the displacement is provided. The print head is engaged with a timing belt operatively coupled to a drive assembly for selectively advancing the belt in one direction either intermittently or continuously. A direction shift assembly is provided for selectively operatively coupling the print head to the timing belt at either of two locations for selectively displacing the print head in opposed directions. The printer also includes a clutch assembly for selectively transmitting unidirectional rotation power from a motor to the timing belt.

Abstract: Carriage space and line feed signals produced between consecutive character print signals are accumulated and logically combined to form a resultant signal rather than being executed as produced. In response to a character print signal, the carriage and line feed are moved in accordance with the resultant signal to the designated position and then the print operation is executed.

Abstract: The present invention discloses herewith a new and novel dot printer for printing characters or the like by a dot matrix, wherein print timing is automatically corrected in relationship to the spacing speed of printing elements so that uneven dot distance is eliminated.

Abstract: Three fixed optical sensing devices are positioned to sense the left and right margins as well as the center location of high speed printer carriage travel. Signals from the sensing devices are fed to programmed carriage logic control circuits which effect rapid carriage movements relative to the center location as well as the traditional left and right margin locations. Printing time of certain forms is greatly reduced by minimizing unnecessary carriage return to the left margin location.

Abstract: A drive arrangement for a single element typewriter in which the element is mounted on a moving carrier, for facilitating proportional spacing incremental movements of the carrier. The carrier is bidirectionally driven by a servo motor which rotates bidirectionally in response to the output of a digital counter. The counter counts in one direction in response to input stepping pulses as well as pulses corresponding to incremental rotational movements of the drive shaft in a given direction, and counts in the other direction in response to pulses corresponding to incremental rotational movements of the drive shaft in the opposite direction. The pulses corresponding to incremental rotational movements of the drive shaft are optically derived from a rotating disk having alternating transparent and opaque radial striations. Provision is made for automatic carrier return by setting the output of the counter accordingly.

Abstract: A carriage and raceway mechanism for an ink jet printer upon which carriage is mounted an ink jet print head for driving the ink jet print head back and forth along the raceway to allow the ink jet print head to eject droplets on a recording medium. The raceway and various other functions are designed and combined into the main frame of the mechanism for simplified construction of the mechanism and lower manufacturing costs. Means for locking the carriage against movement and means for capping and purging the ink jet print head are also provided.

Abstract: A printer including a printing head adapted for reciprocal displacement across a printing tape for effecting printing on the tape in at least one direction of reciprocation is provided. The printer includes a lever pivoted on a frame and adapted to reciprocate the printing head and a rotating disc engaged with a motor for driving the rotary disc which pivots the lever. The rotating disc is adapted to actuate a paper advance assembly, an ink-ribbon winding assembly and an ink-ribbon reversing assembly. The printing head may be of the type including a plurality of needles for recording dots by electromagnetic actuation of the needles.

Abstract: A printer device using thermosensitive paper as a printing medium includes a thermal head for effecting printing on the printing medium, and means for moving the printing medium and the thermal head relative to each other. An electromagnetic plunger and a spring member for urging the thermal head against the printing medium are provided. The plunger serves to control the printing and, in addition, urges the thermal head against the printing medium with a predetermined pressure force, and the spring member is controlled during the relative movement between the thermal head and the printing medium along a print line on the medium, to urge the thermal head against the printing medium with a lower pressure force.

Abstract: The carrier for the print head of a printer which is to be used at different operating speeds as a display printer, as a read-only printer, or as a keyboard display printer with asynchronous character rates over a wide range, is operated by a servo motor under the control of a digital/analog converter which continually sums the outputs of an up/down counter which is incremented by incoming data and decremented by the output of a shift register advanced by the incoming data.

Abstract: Apparatus for printing characters on at least one data carrier comprising a printing head movable along the data carrier, a line advance device for feeding the data carrier substantially perpendicular to the moving direction of the printing head, an ink ribbon feed mechanism for feeding an ink ribbon in relation to the data carrier, a cut-off mechanism for cutting off the data carrier, and a shaft rotatable less than 360.degree. in one direction by a reversible motor from a home position to an end position determined by the selected operation cycle and thereafter back to the home position by reversing the direction of rotation of the shaft. The reversal of the shaft is performed at different times during subsequent operation cycles to permit gears and cams on the shaft to move the printing head to positions determined by the number of characters to be printed on the data carrier, actuation of the line advance device, and actuation of the ink ribbon feed mechanism or cut-off mechanism.

Abstract: The invention relates to a device for returning a carriage driven in translation in a forward stroke by means of a traction wire and returned to its starting position by means of a return spring, wherein said return spring acts on the carriage by means of the traction wire and the traction wire passes around an idle guide pulley and its two ends are wound on coaxial pulleys, of different diameters, rotating with each other. The invention finds particular application to reading and/or writing apparatus.

Abstract: A shifting arrangement is provided for the exact space positioning of a writing carriage for office, teletype or data typewriters in which the writing carriage is moved step-by-step alongside of a record structure in accordance with a predetermined character positioning pattern. The writing carriage is driven by a stepping motor which has a rotary field. A specific number of angle positions of the stepping motor field serve as basic advance positions of the stepping motor in order to compensate for the load angle of the stepping motor during running of the writing carriage. Such basic advance positions are assigned to each character positioning point of the positioning pattern. An electronic device is provided for triggering the rotary field of the stepping motor and automatically adjusting this rotary field to the corresponding basic advance position during running and setting the field to a rest position during stopping of the stepping motor in order to correct for the stepping motor load angle.

Abstract: A carriage for positioning a print mechanism in front of a record medium and moving the print mechanism back and forth in front of the record medium with facility for retracting the print mechanism to permit insertion of a ribbon and biasing the print mechanism forward toward the record medium against an adjustable stop. The retracting mechanism being further adjustable for retracting the printing mechanism completely out of the carriage for removal therefrom.

Abstract: A simplified and compact typing machine to be incorporated in an electronic calculator has a type wheel for presenting different numerals upon rotation. The type wheel is moved along a line of digits, i.e., laterally and in the generally horizontal direction, for typing successive numerals and the typing is performed when a hammer head is swung, or the type wheel is rotated, by the movement in one direction of an acting rod of an electromagnetic relay. The same relay acting rod also laterally moves the type wheel in the direction of the line of digits, on its return motion, by a distance corresponding to the space of one digit.

Abstract: Printing apparatus uses a daisy type print wheel which is continuously driven through a magnetic clutch arrangement. Characters are selected by actuation of either an electromagnetic brake acting on the print wheel or a toothed character selector acting on the spokes of the print wheel. When a character is selected and the print wheel is stopped, rotation of the motor continues because of the slippage of the magnetic clutch. Other features of the invention include a fast recovery time for the hammer because of its constant rate of actuation, a change in spacing by varying this constant rate and also an improved carriage scan technique which provides for fast return.

Abstract: A new and novel dot printer for printing characters of dot matrix or the like by sliding a slide member in the direction of a row, said slide member being provided with a plurality of dot printing elements which are arranged in line thereon at a predetermined distance, wherein plate springs are provided on both ends of the slide member as a guide, support and return mechanism so that guide, support as well as return power are assured for said slide member.

Abstract: An impact printer is provided with an easy load print wheel mechanism. A print wheel cartridge, containing a print wheel therein, is inserted into a print wheel loaded position and removed therefrom without disturbing the position of a print wheel drive motor or ribbon cartridge. The print wheel drive motor shaft is automatically coupled to the print wheel within the cartridge upon insertion of the cartridge into print wheel loaded position.

Abstract: In a print head assembly for calculators and the like, the print head is reversibly driven in a print and return direction transversely of the direction of advancement of the recording medium by a drum segment having a cam drive in the form of an endless helical groove which extends along a cylindrical surface of revolution between opposite ends of a drive axle mounted in driving relation to the print head so that rotation of the drum will impart translational movement to the print head through a suitable drive member engaged by the helical groove at a preselected rate of speed both in the print and return direction.

Abstract: A dot printer for printing characters and the like with a dot matrix which is capable of preventing irregular dot spacings by automatically compensating for the change of print timing resulting from a change in the speed of movement of the printing element.

Abstract: The print wheel and carriage position control signal generators each employ an LED light source for illuminating light sensitive detectors associated with the timing track of an encoder disc rotatably mounted on the print wheel or carriage motor shaft. The detectors are arranged to generate a pair of signal trains having a constant phase displacement in response to rotation of the associated disc. These signal trains are shaped and processed to provide position reference signals used to control an associated position counter unit and an electronic servo control system for driving the associated motor, the servo control system having both a position and a rate mode of operation. A separate light sensor is arranged to be constantly illuminated by the LED source to provide intensity monitoring signals which are compared with a reference voltage in a feedback circuit so that any variation in the light intensity is automatically corrected.

Abstract: A driving mechanism for the carriage of a printer, having a motor with a driving pulley thereon, which has attached to it the ends of left and right cables, each of which is folded at its respective center. The folded portions of the cables are wrapped on a pair of pulleys mounted on the carriage.

Abstract: To more fully utilize the surface area of a typewriter ribbon in a cartridge ribbon receptacle, the cartridge locating plate supporting the receptacle is caused to oscillate with respect to the print head assembly. The ribbon cartridge assembly is a part of a print head and ribbon carrier that is positionable along a line of print by a drive motor through a belt drive engaging a drive pulley rotatably mounted to the carrier. Mounted to rotate with the drive pulley is a cam that engages a cam follower also mounted to the head and ribbon carrier. An upstop forms a part of the cam follower and engages the cartridge locating plate. With the cam follower driven by the cam, an oscillating motion is imparted to the upstop with reference to the head and ribbon carrier which motion is then imparted to the cartridge locating plate. Also fastened to the head and ribbon carrier is a solenoid that when energized spring biases the cartridge locating plate through a leaf spring attached to the plate.

Abstract: Disclosed is a mechanism for replacing the non-escapement magnet normally utilized to inhibit escapement during certain machine functions on a typewriter. A detent arm is connected to the normal pawl knock-off arm so that upon the print shaft rotating and effecting, by a cam thereon, movement of associated linkage and motion of the knock-off arm to disengage the pawl from the ratchet wheel, the detent arm associated with the knock-off arm detents the ratchet wheel and inhibits escapement thereof until the linkage and knock-off arm returns to its normal position by rotation of the print shaft. Thus, if the escapement magnet coil is not energized, the pawl associated with the magnet will return to its normal position and the ratchet wheel will, because of the detent of the member associated with the knock-off arm, be inhibited from motion.

Abstract: In a serial printer a movable type character element such as a ball, disc or the like is rotated to present different type characters to the print position. The carrier for the type element is moved along the print line at a predetermined maximum velocity so long as it is possible to move the type element to the next character in time required to move the carrier from one print position to the next. If the type character set-up time is greater, the carrier is run at a slower speed and is then returned to the predetermined velocity for printing.