Abstract: A wire dot printer having a plurality of ink applicators for separately applying inks of different colors to the ends of printing wires disposed in separate groups in the ink applicators. The ink applicators are supplied respectively with inks of different colors for effecting multicolor printing on a recording paper. The wire groups are separately housed in a plurality of compartments extending longitudinally of the wires and are separated by partitions. The ends of the wires in each group are arranged in an array. The printer may include a cleaning mechanism for removing deposited paper dust and ink from the distal end of the print head while preventing mixing of ink colors.

Abstract: A wire dot printer comprises a plurality of wires for carrying ink respectively on the ends thereof, and ink applicator mechanism applying the ink to the wire, and an ink heater unit disposed adjacent to the wire ends for heating the ink to a controlled temperature level. The ink is applied to the side surfaces of the wires and is drawn to the wire ends by capillary attraction.

Abstract: A wire dot printer using fluid ink in which printing is carried out with the ink adhering to the end faces of the wires. A front wire guide guides the end portions of the wires adjacent to the printing end faces of the wires. A rear wire guide is positioned behind the front wire guide. An ink path fed by capillary action is provided between the front and rear wire guides which crosses the wires at positions adjacent the end faces of the wires. Also disclosed is a pump for conveying the ink within the printer and preferred compositions of the ink itself.

Abstract: A speed control for step motors is provided with a speed control circuit for periodically actuating a motor driving circuit at least in part in response to timing signals representative of the incremental advance of the step motor during acceleration. The time interval between the respective actuations of the motor driving circuit during acceleration is stored in a memory, the speed control circuit actuating the motor driving circuit during deceleration of the step motor at intervals which are a function of the stored acceleration intervals in the memory, applied in reverse order.

Abstract: A pin wheel feed mechanism for transporting documents having feed perforations along the marginal edges thereof. The mechanism includes a pair of symetrically constructed guide frames, each adapted for use on either marginal edge of the feeding document. A pin wheel is rotatably housed in each guide frame and includes a plurality of equiangularly spaced pins which project radially from the surface of each wheel for feeding the document. A notch is provided between each pair of adjacent pins to accommodate warps in the marginal edges of the document to insure positive feed.

Abstract: A linear motor for a printer has stator teeth which are protected from dust and debris generated when the printing mechanism strikes the recording paper by a downward extension of the stator teeth, by a horizontal extension of the stator teeth, or by a horizontal extension of stator teeth which face away from the printing platen. The translating member of the motor to which the printing mechanism is attached has pole teeth spaced from the stator by mechanical rollers. The motor force acts close to the center of gravity of the moving members to reduce mechanical vibrations.

Abstract: In a wire type dot printer head a flat lever pivots on a fulcrum when attracted by an electro-magnetic coil. Pivoting of the lever on the fulcrum drives a print wire or needle, in opposition to a biasing spring, against an ink ribbon and paper for printing on the paper with dots. The biasing spring returns the needle to a stand-by condition after printing. A cantilever spring acts on the lever, being attached near the fulcrum. A spacer sheet, impregnated with a lubricant, is disposed between the lever and the electro-magnetic coil so that lubricant is supplied to the fulcrum of the lever and in the region where the lever engages the print needle or wire. The life of the print head is extended by the availability of lubricant, and the lubricant does not interfere with the printing action. The printer head includes a plurality of similar independently operating needles and drive mechanisms.

Abstract: A printer head for a wire type dot printer including a plurality of printing wires driven by engagement at the input end of the wire with a clapper which is pivoted by a solenoid is provided. The printer head includes a plurality of clappers mounted on the free end of a deflected cantilever, each clapper driven by an electromagnet spaced about the center of the printer head. The clapper is returned to its standby position due to the moment arising at the free end of the cantilever.

Abstract: The printing head for a wire-type dot printer includes a plurality of electromagnet coils, each on a coil core including a central post, said coil core and central post being of a magnetic material. Each of the coil cores is mounted on a frame having a cap for holding an operating plate which rotates around a fulcrum proximate the periphery of the printing head. The printing head is of reduced size and weight and is low in cost to manufacture.

Abstract: A compact flying printer has a continuously rotating print drum and ratchet wheel, a trigger lever positionable to be struck by a tooth of said ratchet wheel and a hammer lever driven by said trigger lever and provided with a print hammer at its end. The trigger lever is formed with a linear guide portion for regulating the motion thereof and an energy-transmitting portion projected for transmitting energy from said ratchet wheel to said hammer level. Paper and ribbon are advanced by selective coupling of a transmitting member to a continuously rotating rotor operated in conjunction with the print drum.

Abstract: A compact flying printer has a continuously rotating print drum and ratchet wheel, a trigger lever positionable to be struck by a tooth of said ratchet wheel and a hammer lever driven by said trigger lever and provided with a print hammer at its end. The trigger lever is formed with a linear guide portion for regulating the motion thereof and an energy-transmitting portion projected for transmitting energy from said ratchet wheel to said hammer lever.

Abstract: A compact flying printer having a continuously rotating print drum and ratchet wheel, a trigger lever positionable to be struck by a tooth of said ratchet wheel and a hammer lever driven by said trigger lever and provided with a print hammer at its end. The trigger lever is formed with a linear guide portion for regulating the motion thereof and an energy transmitting portion projected for transmitting energy from said ratchet wheel to said hammer lever.

Abstract: A printer has a plurality of print hammers displaceable between a rest position and a print position, and respective deformable elastic bodies maintained in a deformed position by each print hammer in its rest position and biasing the print hammer toward its print position. Respective magnetic circuit control means are selectively operable to hold each print hammer in its rest position and to release the print hammer for displacement to the print position by the respective elastic body.