Abstract: The printer is mounted on a desk-top computer and can print both numeric characters and graphic and calculation symbols in two different colors. The characters and the symbols are provided in a relief configuration in accordance with a matrix of rows and columns on a rubber sheet wrapped around a rotatable drum. The characters in adjacent columns are inked by an inking roller formed by adjacent porous discs which are alternately impregnated with red and black ink. The drum can perform a translatory movement in the axial direction selectively to present to the printing hammers the columns of characters which are linked with black and the columns of characters which are linked with red. The drum is translated fixedly with respect to the inking roller by means of a cam which rotates at a speed half the speed of the drum and engaged with one or other of two cam follower pins which can be selected by means of a solenoid.

Abstract: The head (12) comprises a closed container (14) carrying two electrodes (36, 62) and a nozzle (18) and mounted removably on a carriage (13).In order for the ink (16) always to be held at atmospheric pressure, the container (14) comprises an expansible space defined by a diaphragm (67) having a portion (74) aligned with an opening (73) in the container (14).The diaphragm (67) is of butyl rubber which can be pierced with a syringe to permit the container (14) to be refilled with ink (18).The container (14) is closed by an alumina plate (32) carrying the nozzle (18) and joined to a second plate (76) parallel thereto, and of a material which can be wetted by the ink (16). The second plate (76) constitutes a wall for resisting the pressure waves of an ink jet leaving the nozzle (18), and is immediately covered by the ink again.

Abstract: The dot printer, which is of small dimensions, is used with desk top computers or as a peripheral unit with small processors. The printer writes in the serial-parallel mode by means of a thermal head (26) on a paper tape (16) wound on a writing platen (10) which advances intermittently to effect line spacing. This advancing is effected by means of a pawl (56) on a beam (50) controlled by a face cam (46) and a radial cam (48) on a cam cylinder (44) driven by a motor (45). A third cam (42) reciprocates the head (26) and, at the reversals of the head, the face cam (46) allows a spring (45) to engage the pawl (56) with a toothed wheel (62) on the platen (10) and the radial cam (48) then moves the pawl to advance the platen. The head comprises a small plate (29) of insulating material with twenty point-like resistive writing elements, and is fixed to a support (24 ) which is moved parallel to the cylinder by means of the third (42).

Abstract: The printer comprises a solid or liquid ink jet head 100 arranged to print one dot at a time on paper running over a platen 80. The head is carried by a carriage 48 movable transversely with simple harmonic reciprocating motion. In order to reduce the effect of inertial forces when the carriage reverses its movement, the drive is effected by an eccentric peg 70 on a disc 276, the peg engaging in a guide slot 54 of the carriage perpendicular to the direction of reciprocation. An eccentric cam track 71 in the disc engages a peg 92 on a counterweight 90 for counterbalancing the inertial forces of the carriage. In order to synchronize the printing operation with the carriage movement, an optical strobe disc 258 is rigid with the disc 276 and has slots 258 disposed at a pitch varying according to the harmonic motion. The platen 80 is rotated intermittently by a helical cam 277 carried by the disc 276 and a peg wheel 280, 281.

Abstract: The printer comprises a solid or liquid ink jet head 100 arranged to print open dot at a time on paper running over a platen 80. The head is carried by a carriage 48 movable transversely with simple harmonic reciprocating motion. In order to reduce the effect of inertial forces when the carriage reverses its movement, the drive is effected by an eccentric peg 70 on a disc 276, the peg engaging in a guide slot 54 of the carriage perpendicular to the direction of reciprocation. An eccentric cam track 71 in the disc engages a peg 92 on a counter-weight 90 for counterbalancing the inertial forces of the carriage. In order to synchronize the printing operation with the carriage movement, an optical strobe disc 258 is rigid with the disc 276 and has slots 258 disposed at a pitch varying according to the harmonic motion. The platen 80 is rotated intermittently by a helical cam 277 carried by the disc 276 and a peg wheel 280, 281 .

Abstract: A serial dot matrix printer is of the non-impact solid ink type has the ink 102 contained in a tubular container 100 provided at one end with a printing orifice 106. In order to facilitate replacement of empty container, the container is provided with a grip 103 fixed to its central zone, which fits into the space between two resilient fixing forks 95, 96 rigid with the printer carriage 48. The end of the container remote from the orifice 106 is closed by a cap 110 which engaged by an electric contact 116 and connects to the ink rod 102 through a spring 107, for establishing the operating voltage between the ink rod and a counter-electrode 89 in the form of a laminar spring guiding the paper 82 round a platen 80.

Abstract: A non-impact printing method with selective emission of solid ink particles is disclosed. A rod of solid ink is spring-pressed in an insulating housing against an end wall with a nozzle therein. A pulsed high voltage applied between the ink rod and a counter-electrode (which can be behind a paper target) causes ink particles to be eroded from the rod and ejected through the nozzle onto the paper. The method includes incremental line-feed paper movement, movement of printing devices as just described along the printing line, and selective control of the high-voltage pulsing such as to form characters by a dot matrix technique.

Abstract: A solid ink cartridge for a non-impact printer with emission of solid ink particles is disclosed. A rod of solid ink is spring-pressed in an insulating housing against an end wall with a nozzle therein. A pulsed high voltage applied between the ink rod and a counter-electrode (which can be behind a paper target) causes ink particles to be eroded from the rod and ejected through the nozzle onto the paper. The printer includes incremental line-feed paper movement, movement of printing devices as just described along the printing line, and selective control of the high-voltage pulsing such as to form characters by a dot matrix technique.

Abstract: A non-impact printing device with selective emission of solid ink particles is disclosed. A rod 19 of solid ink is pressed by a spring 20 in an insulating housing II against an end wall with a nozzle 13 therein. A pulsed high voltage applied between the ink rod and a counter-electrode 16 (which can be behind the paper 25) causes ink particles to be eroded from the rod and ejected through the nozzle on the paper. Printers are described which employ incremental line-feed paper movement, movement of printing devices as just described along the printing line, and selective control of the high-voltage pulsing such as to form characters by a dot matrix technique.

Abstract: A dot matrix printing device for electronic calculator comprising a plurality of electrically heatable dots of an insulating plate aligned therebetween and spaced according to a constant pitch to print the digits of the calculator amounts. A symbol dot is located adjacently to the terminal digit dot which prints the least significant digit of the amount, aligned with the other dots of the plurality. The symbol dot is spaced from the terminal digit dot by a distance greater than the constant pitch of the other dots and prints the explanatory symbols of the amounts leaving a blank between the digits and the symbols of the amounts.