Abstract: A printer system using a cassette housing therein printing ribbon is provided. In accordance with one aspect of the present invention, there is provided a cassette provided with an electrically conductive sheet for preventing the cassette from accumulating charge. In accordance with another aspect of the present invention, there is provided a thermal printing process in which a heat-sensitive ink ribbon is separated away from a recording medium while the ink is still half-melted thereby allowing to prevent a printed image from becoming reflective. In accordance with a further aspect of the present invention, there is provided a printer system in which a printing ribbon is extended as inclined with respect to a recording medium such that the printing ribbon is separated farther away from the recording medium in a printing direction.

Abstract: A printer having a daisy type-wheel or the like comprises a carrier longitudinally movable along a platen and a carriage detachably and pivotally mounted on the carrier. Mounted on the carriage are a ribbon cartridge, the type-wheel, a hammer assembly and a magnet assembly for actuating the hammer assembly. The design of the printer permits easy and accurate positioning and adjustment of constituents of the carriage, easy and accurate attachment of the carriage to the carrier, and easy tilting of the carriage for replacement of the type-wheel. Shifting of the type-wheel is achieved rapidly and with the low vibration. The ribbon cartridge may be moved from a non-printing to a printing position easily, with low vibration and with little generation of noise. The U-shaped ribbon cartridge includes an engaging member extending from a front leg of the cartridge toward the inside of the U-shape.

Abstract: An apparatus for driving a floppy disc includes a first sensor responsive to a magnetic disc encased in a jacket of the floppy disc. Before the magnetic disc is gripper in a predetermined position, a d.c. motor included in a disc rotating mechanism is started in order to prevent rush current therethrough. After the start of the d.c. motor, a second sensor senses a return of the magnetic disc to a predetermined regular position whereupon a cone load drive source is activated to automatically move a cone toward a drive hub. Thus, the magnetic disc can be gripped and set in the regular position merely by inserting it into the apparatus. The apparatus also includes ejection apparatus for ejecting the floppy disc.

Abstract: An ink ribbon feeding mechanism includes a rotatably supported capstan roller which is fixed in position and a rotatably supported pinch roller which is movable with respect to the capstan roller and normally biased toward the capstan roller to be pressed thereagainst with ink ribbon to be fed as being sandwiched therebetween. In the present invention, there is provided a structure which allows to keep the pinch roller separated away from the capstan roller when desired. In the preferred embodiment, it is so structured that the pinch roller is brought into contact with the capstan roller under pressure when a top cover is pivoted closed and brought out of contact with the capstan roller when the top cover is pivoted open, automatically.

Abstract: A thermal printer for printing characters or the like on a recording medium, heat-sensitive paper or plain paper, by a thermal printhead which is mounted on a carriage movable along the recording medium in a reciprocating manner is provided. The printhead is pressed against the recording medium while the carriage is moving in a printing direction and the printhead is kept away from the recording medium while the carriage is moving in a returning direction opposite to the printing direction. A cassette containing therein heat-sensitive ink ribbon is substantially elongated in shape and it bridges between a pair of side plates forming part of a frame of the printer when detachably mounted in position. The cassette is provided with a supply port at one end and a take-up port at the opposite end and thus the ribbon is lead outside through the supply port and lead inside through the take-up port. And the ribbon is taken up in association with the returning motion of the carriage.

Abstract: A printer having a type wheel of the daisy wheel type or the like, which is improved to permit an easy position adjustment of constituents of the type wheel driving mechanism, as well as an easy tilting motion of the carriage in relation to the carrier and an easy attaching of the carriage. Also, the shift of the type wheel can be achieved rapidly and with a light force and the ribbon cartridge can be moved with a light force while suppressing generation of noise.

Abstract: A ribbon cartridge engageable with an upper stopper member of a cartridge receiving apparatus which includes a cartridge body of substantially U-shaped form having at least one front leg member and an engaging member extending from the at least one front leg member of the cartridge body for engagement with the upper stopper member so as to secure the cartridge body in a predetermined position with respect to the cartridge receiving apparatus. The engaging member extends from a bottom portion of the cartridge body and further includes a reinforcement portion cooperably connected to the engaging member. The cartridge body is engageable with at least one holding member of the cartridge receiving apparatus and the cartridge body includes at least one retaining lug engageable with the at least one holding member for positioning the cartridge with respect to the cartridge receiving apparatus.

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: A hammer device for a printer includes a hammer bullet which is made up of a detent and a rectangular rigid part. One lateral edge of the rigid part is slidably guided by flanged rotary bearings located at a reference side while the other lateral edge is slidably guided by another flanged rotary bearing located at the opposite side. This causes the hammer bullet to perform true translation toward and away from a type wheel so that the detent is engagable with a desired fount detent to print a character of an excellent quality.

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: A disc rotatable with the motor shaft has circumferentially equally spaced slots formed therethrough. A light source and receiver assembly are operatively arranged relative to the slots to produce pulses representing a predetermined angular displacement of the motor shaft determined by the width of the slots as the motor shaft rotates. The duration of the pulses decreases as the motor shaft speed increases. A multivibrator is triggered by the leading edges of the pulses to generate reference pulses of a predetermined duration. The motor phases are excited in a normal sequence as long as the duration of the pulses is longer than the duration of the reference pulses. When the pulse duration becomes less than the reference pulse duration, coincidence sensing means alter the phase excitation during the times between the termination of the pulses and the termination of the respective reference pulses to apply a torque to the motor shaft in such a manner as to prevent the motor shaft from accelerating further.

Abstract: A disc rotatable with the motor shaft has circumferentially equally spaced slots formed therethrough between the motor step positions. A light source and receiver assembly are operatively arranged relative to the slots to produce position pulses when the motor shaft is positioned between steps. Since the motor shaft varies during operation, the widths of the position pulses also vary in proportion to the motor shaft speed. Timing pulse generators are arranged to generate timing pulses of fixed duration at various motor shafts spacings before the desired stopping position. The coincidence between the timing pulses and the position pulses is sensed, and the motor phases are switched to apply reverse torque to the motor shaft during the intervals of coincidence or non-coincidence of the timing pulses and position pulses.