Abstract: A serial printer comprises a carriage (21) which is movable parallel to a platen roller (11) and on which are mounted a character carrying disc (28) having a flexible blades, a stepping motor (26) for selecting the character to be printed, and a striker hammer (30, 31). The carriage is slidable on a cylindrical guide (17) and is provided with a pair of slider members (62, 63) which co-operate with a fixed bar (18) that is parallel to the guide (17) and to the platen roller (11). Mounted on the fixed bar (18) at the left-hand side of the printer is a key (70) which can co-operate with the slider members (62, 63) of the carriage to disconnect them from the bar (18) and to permit the carriage (21) to be swung down so that the character carrying disc (28) can be easily removed and replaced.

Abstract: A printing apparatus includes a power supply for supplying power thereto and a battery supply for supplying back-up battery power. A printing mechanism effects printing on a printing paper in accordance with one of a plurality of printing pitches, and a processor controls the printer and produces data signals. A selector selects one of a plurality of printing pitches and applies a signal indicating the selected printing pitch to the processor. A plurality of indicators each indicates a respective one of the plurality of printing pitches and one of the indicators is energized by a data signal produced by the processor. A memory is supplied with back-up battery power by the battery power supply and stores a selected one of the plurality of printing pitches. The memory is accessed by the processor.

Abstract: A printer having a print head with a mounting portion, and a carriage with a supporting structure engaging the mounting portion of the print head to hold it in place on the carriage. The supporting structure includes a lateral positioning portion for positioning the print head laterally in a direction of movement of the carriage, a downward positioning portion for positioning the print head downwardly of the carriage, and a rear wall for receiving a force of reaction of the print head upon printing action on a platen. The printer comprises a biasing device for biasing the mounting portion of the print head downwardly and rearwardly against the downward positioning portion and rear wall of the supporting structure of the carriage, respectively. The carriage may include a serrated portion fixedly engaging a toothed belt for driving the carriage along the platen.

Abstract: A printing apparatus having a platen for supporting a sheet of paper, comprising: a carriage movable along the length of the platen, and including an upward protrusion having a top surface which includes a first slant part inclined downwardly in a direction toward the platen; a print head including a mounting portion resting on the upward protrusion, the mounting portion having a bottom surface which includes a second slant part in abutting contact with the first slant part; and a fixing device for clamping the mounting portion of the print head to the upward projection of the carriage substantially in a direction of height of the upward protrusion. An angle of inclination of the first and second slant parts being selected such that a clamping action of the fixing device produces a component force sufficient to force a portion of the print head against a side surface of the protrusion on its side opposite to the side facing the platen.

Abstract: A reciprocating drive mechanism, capable of producing a substantially trapezoidal velocity profile, reciprocates the hammer banks of a dot matrix printer, or printers in general, at a relatively high frequency (40 HZ), and a high constant velocity (34 to 40 in/sec). Utilizing a set of non-linear springs, the hammer banks are reciprocated at one of the many possible resonant frequencies of the non-linear spring mass system, thus minimizing power consumption. Single action solenoids or a voice coil type motor is servo controlled to compensate for the energy loss due to damping. An optical switch establishes the zero position of the hammer banks at midlength of the travel. A velocity transducer measures the velocities at all positions. By integrating the velocities, the positions at any time of travel is known for proper placement of the print dots.

Abstract: A handy type printer with dry cells incorporated therein in which an arrangement consisting of dry cells and a paper feed motor aligned, a screw shaft for sliding a head therealong and a head-driving motor are disposed in the order named in parallel with each other; the ends of a platen and the head-driving screw shaft are supported by first and second shaft bearing members, respectively; and a plurality of reduction gears are rotatably mounted on the first shaft bearing member so as to transmit the torques of the paper feed motor and the head-driving motor to the platen and the head-driving screw shaft, respectively.

Abstract: In an electronic correcting typewriter, a character correction and replacement system is disclosed for facilitating the task of correcting typed character errors. The typewriter includes a printing and a correcting mechanism operated under electronic control and a correction buffer is associated with the electronic control for storing the last plurality of printed characters. To automatically erase any previously printed character which character has its code stored in the correction buffer and print a new replacement character, the typist locates the carrier opposite the unwanted character and actuates the character key of the desired replacement character. Under control of the electronics, the unwanted character code is recalled from the correction buffer, the correcting mechanism is operated to erase that character and the printing mechanism is operated to print the new character. Operator setting of an overstrike flag provides character overprint capability.

Abstract: A printer in which a platen is secured to a machine frame, a carriage is movably supported on the machine frame for movement along the platen, a motor is movably supported on the carriage for reciprocal movement in a direction at right angles to the direction of movement of the carriage towards and away from the platen, a pedal type wheel is fixedly secured to the carriage and has a plurality of types, mating coupling means is formed on each of the motor and type wheel, detection means is provided to generate a detection signal upon detection of a particular rotational angle of the motor during one complete rotation of the motor, a drive circuit is provided to drive the motor and a control circuit is provided to determine presence of a detection signal and arrests the rotation of the motor when no detection signal is generated within a predetermined time period required for the motor to rotate one complete rotation.

Abstract: A device is provided for guiding a print element of a printer device. The guide device comprises a guide bushing which is provided with two sliding surfaces and which is carried on a guide rail facing the platen. A support mount is engaged over the guide bushing and has a projection for fastening a traction device, such as a toothed belt, of a drive system. The support mount also has latch openings for receiving latch pieces for accurate positioning of the print element. The print element further comprises a fork-like guide projection to be received over and for sliding along a second guide rail. In order to fasten the print element to the guide bushing, a resilient snap-in clip is held constantly locked at the print element, the snap-in clip being pivotal so as to partially embrace the guide bushing and has projecting ends which are freely accessible for unlatching of the clip.

Abstract: A vibration isolating coupling ideally suited for coupling the bobbin (31) of a linear actuator (23) to a flexure supported printer carriage (11) is disclosed. The two main sources of vibration in a system that includes a flexure (13, 15) supported carriage coupled to a linear actuator (23) are low-frequency vibration resulting from the pivot arc motion of the flexures (13, 15), and high frequency vibration resulting from the change in bobbin shape occurs as AC energy is applied to the bobbin (31). The first source of vibration is reduced by configuring the interface plane between the linear actuator and the flexure supported carriage such that contact occurs at spaced apart points located on either side of the flexure movement plane. Preferably, four contact points equally spaced from the flexure motion plane are used. The region between the contact points and the flexure motion plane is cut out so that no contact occurs in and on either side of the flexure motion plane.

Abstract: A printing mechanism is provided with a counter-balanced hammer bank such that the hammer bank and a counterweight are oppositely reciprocated by a pair of cams mounted on a vertically oriented cam shaft. Vibration of the printer even at high speed can be eliminated by completely dynamically balancing the system.

Abstract: A print head carriage assembly having a precision, linear, ball-bearing slide mounted parallel to the platen. The device has a carriage which is supported by the inner member of the slide. The linear movement of the carriage is also controlled by a second guide which is likewise mounted parallel to the platen.

Abstract: The printer includes a print head moveable in a lateral direction perpendicular to the feeding direction of a sheet of recording paper. The print head is supported on a carriage which is reciprocably driven. Different paper feed pitches are selectable depending upon the lateral position of the carriage at the end of printing. A paper feed cam includes two or more feed grooves and pitch changing grooves connecting the feed grooves so that the paper feed means can operate from any selected one of the feed grooves. A cam follower connected to the carriage rides in a groove causing the paper feed cam to be driven by motion of the carriage. Different feed pitches for graphics and text are provided.

Abstract: The printer is for printing on a narrow print-receiving medium such as a ticket (T) which passes lengthwise through the printer. The printer includes an anvil or platen which is at least partially constituted by a cylindrical roller (150) capable of rotating about its own axis (322) in such a manner that its cylindrical surface accompanies the movement of the narrow medium substantially without slipping. A dot-matrix print head is movable in translation transversely to the motion of the medium so as to print thereon against a generator line of the roller. The improvement lies in the printer further including a unitary guide assembly (301, 302, 307, 313) for guiding both rotation of the roller and translation of the print head.

Abstract: A horizontal printing type printer including a head feeding motor serving as a shaft feeding motor; a feeding shaft coupled to the motor so that it is rotatable in both directions, the shaft being arranged in a vertical direction perpendicular to the printing line direction; two sheet feeding tractors mounted on the shaft, two one-way clutches provided on the tractors, respectively, the one-way clutches being engaged with the shaft to rotate together with the latter in the sheet feeding direction to feed the printing sheet; and a printing head movably supported on the shaft and a guide rod parallel with the latter, the printing head being moved backwards and forwards in the vertical direction of rotation of the shaft.

Abstract: A printer apparatus including a printhead (14) for printing on a data carrier (20), a printhead carrier (15) for moving the printhead along a path, a cutter mechanism (30) for cutting the data carrier upon command, a bi-directional drive means (34) having an output shaft (36) operable to be driven in first and second directions and a one-way clutch means (46) operatively associated with the output shaft for actuating the cutter mechanism (30) and driving the printhead carrier (14). The drive means when effecting rotation of the output shaft (36) in the first direction effecting movement of the printhead carrier and printhead along the path and when effecting rotation of the output shaft in the second direction effecting actuation of the cutter mechanism (30) to cut the data carrier.

Abstract: A drive control system for controlling a drive motor in response to external command signals. The system comprises a first control arrangement for obtaining numerical values corresponding to amounts of successive intermittent operations of the drive motor responsive to respective external command signals, summing the obtained numerical values, and subtracting from a current sum of the numerical values a numerical value corresponding to a non-operation time period during which the drive motor is held at rest between the successive intermittent operations. The system further comprises a second control arrangement for inhibiting the operation of the drive motor responsive to the next command signal, for a length of time corresponding to the current sum after the drive motor has completed each of the intermittent operations, whereby the temperature of the drive motor is kept below an upper limit.

Abstract: A dot matrix line printer incorporates plural print element driver assemblies each including N electromagnets driving N print rods, with each electromagnet having a local magnetic circuit that includes a working air gap and a passive air gap; a permanent magnet is connected to all of the local magnetic circuits. A magnetic circuit connects all of the local passive air gaps in parallel to afford a passive air gap common to all local circuits, the reluctance of the common passive air gap being of the order of 1/N times the maximum effective reluctance of the working air gap of each electromagnet. Each armature is supported by a cantilever bias spring, biasing the armature and associated print rod away from the electromagnet poles toward a print position; a stop member progressively reduces the effective length of the cantilever spring as the armature moves toward the electromagnet poles.

Abstract: A print head carriage assembly is provided which is especially suitable for use in a thermal dot matrix character printer. The assembly includes a belt, which in one embodiment is formed of laminations of film. The belt is formed into a loop with a free end by a tensioning device; the belt loop tautly passes around a pair of guides, one of which is bidirectionally rotatable to transport a print head clipped to the loop between the two guides and across a platen. The control signals to the print head are passed via conductors affixed to the belt from the free end of the belt to the print head.

Abstract: Hammer actuators are mounted on a support. Instead of moving the entire massive support to traverse the paper for each line, only a low inertia member, which positions the impact ends of the print wires, is moved. The internal structure of the member facilitates minor curvature of the print wires as the member moves. The member is rapidly reciprocated relative to the support, but "dwells" for a short time at each extreme to permit indexing of the paper. Ehnanced graphic capability is possible because each print wire can print a plurality of dots for each line.

Abstract: To enable a microprocessor to operate within its bandwidth limitations while controlling a serial printer, means are provided for adjusting the microprocessor system clock rate when the printer is in its rate mode. In particular, the output of a counter clocked by the pulses from an encoder representing the velocity of a member is controlled; the output of the counter being selectively applied to the microprocessor in accordance with the velocity of the member being controlled.

Abstract: Disclosed is a serial printer comprising a carriage loaded with a printing head and moved in the horizontal direction, wherein a motor is contained in the carriage, a pinion is attached to a rotor shaft of the motor, a rack engaged with this pinion is attached onto a guide rail for movably supporting the carriage and the carriage loaded with the printing head is moved along the rack by rotating the pinion engaged with the rack by rotation of the motor.In this serial printer, the power loss of the motor due to the presence of an intermediate power transmitting member indispensable for the conventional printer, such as a wire rope, a toothed belt or a screw shaft, can be eliminated, and occurrence of troubles due to stretching or deformation of this intermediate power transmitting member is prevented. Accordingly, the capacity of moving and positioning the printing head is increased.

Abstract: A linear capacitive encoder is utilized for detecting and encoding the position of a movable member such as a print bar in a dot matrix impact printer. An eight-phase signal is capacitively coupled to one plate of a linear capacitor mounted on the movable print bar. When the print bar moves the phase of the coupled signal changes with respect to the phase of the signal on the other plate of the capacitor, producing an analog signal representing incremental movements of the print bar. The analog signal is amplified and filtered and then converted to a TTL signal representing the position of the print bar. Present position of the print bar is compared to previous position of the print bar to derive signals representing the present direction of movement, direction change and incremental movements of 0.001". Built-in error or hysteresis is added to the direction and direction change signals to prevent false direction changes due to noise. The 0.

Abstract: A serial printer suitable for use in desk-top calculators or the like. The serial printer has a rotary shaft rotatable together with two type wheels. The power supply to the rotary shaft is made by a motor which operates continuously only in one rotational direction through a first clutch. A second clutch is provided to make a selective power transmission between the rotary shaft and the member for actuating the hammer, as well as the member for causing the carrying operation. The states of the first and the second clutches are controlled by a change-over arm which in accordance with the operation instruction given by an operation instruction coil, such that these clutches are alternatingly turned on and off to make various operations such as printing, column shift, paper feeding and so forth.

Abstract: An assembly for mounting deflection rollers about which a belt extending between machine side walls is trained comprises plug-in parts which enable the deflection rollers to be assembled one to one machine side wall, and the other to a guide plate supported by and adjustably spaced outwardly of another side wall with the spacing establishing belt tension which holds the assembly together. The guide plate also mounts a detector for monitoring the rotary position of the deflection roller.

Abstract: A printing timing correction device in a shuttle type dot line printer wherein a shuttle is reciprocated in directions perpendicularly intersecting a direction of feeding printing paper, printing needles regularly arranged on the shuttle are projected to recording paper to thereby conduct desirable printing operations and the shuttle performs non-constant velocity motion for which the rotation of a driving motor is transmitted by a crank mechanism.The printing timings are varied against the printing needles performing non-constant velocity motion in accordance with the speed of the printing needles, whereby the printings are performed at equal interval positions on the printing paper. This correction is performed by varying the delay time periods of signals fed to the printing needle driving device.

Abstract: Positioning device for a printer comprising a type carrier daisy wheel fitted on a carriage movable in front of the platen. The selection of type and movement of carriage are carried out by selection and transport motors of direct current type which are controlled by velocity servo motors through corresponding digital transducer and position counters. After a coarse positioning by the servo motor, the exact final position is reached and kept by exciting a couple of magnetic positioners whose rotor is keyed on the axes of the selection and transport motors.Economic solutions are also described to synchronize, during initialization of the machine, the content of the position counters with the effective positions of the daisy wheel and carriage.

Abstract: A printer having a print wheel rotatable on a carriage. The carriage is guided for movement parallel to a platen. The printer may print at either a fast speed for draft quality output, or a slower speed for highest quality output. The lesser quality of output produced at the fast speed is more than adequate for draft documents.

Abstract: A typewriter printing assembly is disclosed in which a typing assembly and type actuator are mounted for movement along a shaft and are connected to a follower. The connection of the typing assembly and follower is a detachable one, and the support for the shaft is removable for facile assembly and disassembly of the typing assembly on the shaft. The type actuator comprises a light interfitting assembly of the type hammer and support formed to accommodate the shaft and for straight line movement of the hammer when activated.

Abstract: An improved daisy-wheel printer of the type in which a hammer contacts a daisy-wheel to print characters is designed so as to facilitate the position setting of the hammer and other movable parts for actuating the type head. According to the design, it is possible to shift the type head with a reduced force and to eliminate the necessity for the adjustment of same during assembly. The stability and tilting operation of the carriage is enhanced. The carriage is stably secured, eliminating lateral oscillation of the same without the necessity of manufacturing the carriage using highly precise machining. The ribbon cartridge is held in such a manner as to be able to move rapidly, with reduced generation of vibration and with high durability. The design facilitates the determination of relative positions of constituents of the magnet device which drives the hammer, and facilitates fine adjustment of the same. The magnet assembly includes a substrate and an arm extending from the substrate.

Abstract: An electronic printer mechanism having a movable printhead assembly , wherein the printhead is a matrix of selectively heatable semiconductor mesas for producing dot matrix characters one line at a time on a paper medium. The electronic printer mechanism is constructed with a sectional housing including upper and lower housing sections which are releasably secured together to define an interior chamber for receiving components of the electronic printer. The lower housing section is provided with complementary sets of shaft-receiving recesses such that drop-in assembly of components with respect to the lower housing section as received in respective sets of the recesses prior to securement of the upper and lower housing sections together is accomplished. One component assembly comprises an operating shaft on which the printhead assembly including a carrier member fixedly supporting a printhead is mounted for transversing movement therealong.

Abstract: A serial printer for printing on a thermosensitive recording medium. The printer includes a frame having a carriage supported thereon for lateral movement across the recording medium. A thermal print head is supported on the carriage for lateral displacement therewith for printing on the recording medium. A platen is supported on the frame for supporting the recording medium so that the print head can be pressed against the recording medium to effect thermal printing thereon. A motor having a relatively flat configuration is supported on the frame and includes a vertical rotatable shaft which is rotated by the motor. A drive gear system is operatively coupled to the rotatable shaft of the motor for selective rotation thereby in opposite directions in response to rotation by the motor. A conversion mechanism converts rotation of the drive gear into lateral movement of the carriage.

Abstract: In a printer in which a shuttle and a counterbalancing mass are driven in opposing reciprocating fashion by a rotating, generally oval-shaped cam, the cam followers which couple the shuttle and the counterbalancing mass to the cam are castered to prevent skewing of the cam followers relative to the cam. Each of the cam followers is disposed between and rotatably mounted on a pair of opposite arms extending outwardly from a generally planar base of a castered yoke assembly, the planar base being pivotally coupled to a supporting member therefor which is either coupled to the shuttle or forms a part of the counterbalancing mass. In a first embodiment the pair of opposite arms extend from the planar base toward the cam so as to dispose the cam follower between the pivotal mount of the yoke assembly and the cam.

Abstract: A printing mechanism includes a right-angle drive for imparting rotation to a rotary printing element having printing type thereon, rotation of the print element selecting a specific character to be imprinted on a printing medium. The right-angle drive permits the printing element to be moved transversely of the printing medium while receiving rotational mechanical signals for imparting the requisite rotation to the printing element. A shaft having a longitudinal keyway therein passes though a bevel gear of the right-angle drive, there being a key extending from the gear to the keyway to permit the sliding of the gear along the shaft while being controlled in rotation thereabout. A carriage carrying the rotary print element and the right-angle drive is driven in the transverse direction by a worm gear having a worm surface provided with inclined sides which mate with a pair of angled inclined rollers supported by the carriage for engagement with the worm gear.

Abstract: An adjustable diameter pulley, particularly suitable for the belt tension adjustment in belt transmission system such as those used in serial printers, utilizing a central core having a tapered portion, a threaded cylindrical portion and also a plastic ring having external cylindrical surface and a central tapered opening. The opening receives the conical portion of the core and is provided with deep slits which allow its expansion. A second ring, screwed on the cylindrical portion of the core, causes the expansion of the plastic ring to vary.

Abstract: A transport system for a dot matrix printing mechanism including an improved overall design for the transport system and improved designs for individual elements of the system and combinations of elements. The overall design of the present invention uses snap fits extensively throughout for ease of assembly and disassembly, integrates many previously separate parts into one-piece members, employs common part designs wherever possible, and uses single parts to perform multiple functions wherever possible. For example, the striker bar and ribbon frame of the system are combined into one piece and the ribbon cartridge is releasably mounted to the ribbon frame using one end of a latch member while the other end of the latch member is used to bias a pressure roller against the paper advancing roller. The overall design also includes a common drive train interconnected between the moving parts of the system whereby all of the moving parts can be powered by a single motor.

Abstract: A servomotor drive system for a printer escapement is provided which minimizes power supply requirements. The drive system has means for accelerating and decelerating the printhead escapement having a fixed current source applied to a servomotor which drives the escapement. In order to minimize power requirements, the system includes means for controlling the current in the motor which comprise means for sensing the actual motor current and feeding back the sensed current to a comparing means. A preselected varying current profile is applied to the comparing means which compares this profile to the actual motor current. Means are then provided responsive to these comparing means for altering the actual motor current to conform with this preselected varying motor current profile.

Abstract: The present invention discloses a serial printer for reciprocating a carrier along a platen by means of a wire, wherein the wire is connected to a wire retainer, which is a member separated from the carrier, to form a wire route, the carrier being detachably mounted on the wire retainer whereby the carrier may be removed with the wire remained stretched. Maintenance, checking and repair are easily accomplished and initial assembling is accomplished in a very simple manner.

Abstract: A machine for stamping characters in multiple rows on a workpiece is disclosed. The machine includes an impact head assembly mounted on a transversely slidable carriage, the impact head assembly being adapted for reciprocating movement perpendicular to the path of that sliding movement. A rotating stamping wheel is mounted in the impact head assembly and has a plurality of character stamps mounted on its periphery. Means are disposed in the impact head assembly for moving the stamping wheel to a plurality of selected positions along its axis of rotation.

Abstract: A serial printer is provided which moves the printhead at optimum velocity with respect to the document being printed so as to achieve maximum throughput. Prior to the printing of each line of alphanumeric characters, the printer contains means for determining the length of said line. In response to said determined line length, drive means move the printhead across the medium at a selected velocity which is based upon the determined line length. The present expedient is particularly applicable to matrix printers wherein the selected velocity is constant during the actual printing of the line.

Abstract: A detachable carriage assembly for a printer having a frame for supporting a cylindrical platen and a drive motor for moving said carriage assembly and comprising first and second parallel supports mounted in spaced apart relationship on the frame of the printer parallel to the platen, a pulley support assembly movably mounted on one of the supports and connected to the drive motor for movement parallel to the one support, a bearing assembly slidably mounted on the other of the supports and a carriage assembly detachably mounted to the pulley support assembly and the bearing assembly for moving parallel to the platen as the pulley support assembly moves.

Abstract: A printer employing a movable print carriage is fitted with a single rigid bar-like carriage support structure having three very narrow, low friction, plain guideways, either grooves or rails, kinematically arranged for extremely accurate guiding of the printing carriage as it moves along the writing line. The print carriage is fitted with kinematically arranged mechanically reciprocal guides for engaging the guideway grooves or rails. The carriage support structure is made sufficiently rigid and massive to also serve as the printer frame for supporting the platen and other printer parts and elements. The location of the three guideways, primary feed roller bearing supports, platen supports, and platen adjustment rod bearings are such that all can be machined in one set-up in a multiple spindle machine tool so as to achieve exact parallelism of all the elements requiring precise alignment.

Abstract: A serial printing mechanism which employs a type wheel having a plurality of type characters has a single motor mounted on a carriage employed to accomplish plural functions. The single motor selectively rotates the type wheel to locate the predetermined type character in front of the typing position, and shifts the carriage. The carriage drive which shifts the carriage along a platen is powered by the single motor through a clutch which selectively engages the motor with the carriage drive.

Abstract: A serial impact printer 11 includes a frame 15 mounted drive motor 47 coupled to a print wheel 31 to effect rotation thereof. The print wheel 31 is mounted on a movable print carrier 29 which serially moves from print position to print position along the print line. The motor 47 is coupled to the wheel pulley 51 of the print wheel 31 through a belt 49 which is wrapped about two idler pulleys 57 and 59 located on a sub-carrier 61. The sub-carrier 61 moves one half the distance of the print carrier 29 so that during escapement motion of the print carrier 29, the belt 49 imparts no rotary motion to the wheel pulley 51 and hence to the print wheel 31. The print carrier 29 may be clamped by clamp 77 to the belt 49 to effect the return motion thereof. The motor 47 is also coupled through a clutch 127 to the line feed apparatus of the platen 23.

Abstract: The print head of a serial printer includes a protruding plug which is seated and locked into a receptacle on a translating carriage. An endless belt has teeth engaged in a correspondingly contoured groove of the carriage for positive connection between carriage and belt, whereby the head traverses the printing medium for printing thereon. The platen is positively and simply held and includes a resin surface for impact of print wires. The gap between the head and platen is readily adjusted in steps by motion of a lever.

Abstract: A dot matrix printer having a printer hammer bank carried on a frame to allow movement parallel to the platen. A balancing member is suspended from the head hammer bank by resilient springs and carries a motor for driving the head hammer bank in a reciprocating manner. A linkage further couples the head hammer bank and the balancing member so that the balancing member moves in a direction opposite to that of the head hammer bank.

Abstract: A serial printer is provided with a moving coil type linear motor operated printer carriage, wherein the magnetic field produced by a magnetic circuit of the linear motor is greatest at the opposite ends of the print stroke. The areas of increased magnetic field allow the printer carriage to be quickly accelerated up to the uniform speed at which printing takes place, as well as the deceleration of the carriage as it approaches the end of the print stroke.

Abstract: A single stepper motor is utilized in a printing device to lift a print head from the surface of recording material upon the initial angular rotation of the stepper motor output drive shaft and to move the recording material within the printing device upon further rotation of said drive shaft. The print head is returned to the surface of the recording material by operating the stepper motor in the reverse direction until the output drive shaft of the stepper motor traverses an angular displacement equal but opposite to the initial angular displacement. A cam surface couples the output drive shaft of the stepper motor to a drive gear and transforms the initial angular displacement of the output drive shaft into linear motion to lift the print head from the surface of the recording material. Further rotation of the stepper motor drive shaft rotates the drive gear to move material within the printing device.

Abstract: A small printer for printing characters on a printing medium especially adapted for use in a portable electronic calculator. The printer includes a frame having a carriage slidably mounted thereon for lateral displacement across the printing medium. An ink jet printing mechanism is carried on the carriage for selectively printing characters at predetermined positions along lines of the printing medium. A crank mechanism couples a motor to the carriage so that the printing mechanism can be translated across the printing medium. A printing position control circuit determines when the printing mechanism is in each predetermined printing position and selectively supplies a printing signal to the printing mechanism so that the printing mechanism will print a character at the selected predetermined positions.

Abstract: A manually operated dot printer designed for use in a pocket sized calculator or a small sized electronic device includes a printing head which is manually movable across a sheet of printing paper in one direction. A pulse generating circuit produces a signal in synchronization with the speed of travel of the printing head. While the printing head is moving in said one direction, the printing head effects electrically controlled printing operations with dots in response to the signal produced by the pulse generating circuit. As the printing head is advanced, spring means store energy which is applied to return the printing head and advance the printing paper.