Invertible inked ribbon cartridge having two sets of feed mechanisms for an impact-serial printer

#The present invention relates to an inked ribbon cartridge for an impact-serial printer, and more particularly to a film ribbon cartridge for use in an impact-serial printer or electronic typewriter which is required to have a high quality.

#Heretofore, serial printers have used an inked ribbon such as a cloth ribbon and a carbon film ribbon, and recently in order to improve the lifetime of the inked ribbon, the inked ribbon has been contained in a cartridge. To obtain a high printing quality a carbon film ribbon has been contained in the cartridge. However, in view of the nature of the film, it is impossible to form a cartridge having an endless structure which could be repeatedly used for printing as is the case with the inked cloth ribbon. Accordingly, in the case of a film ribbon cartridge, the life of the ribbon is extremely short as compared to a cloth ribbon cartridge, and hence it has a disadvantage in that the cost of the ribbon is high.

#It is therefore an object of the present invention to provide an inked ribbon cartridge in which the life of the inked ribbon is extended.

#Other features and advantages of the present invention will be apparent from the following description of preferred embodiments of the present invention taken in conjunction with the accompanying drawing, wherein;

#FIG. 1 is a plan view of a first embodiment of the present invention;

#FIG. 2 is a plan view of the first embodiment shown in FIG. 1 with a cover removed;

#Referring to FIGS. 1 and 2, feed drive rollers 2A and 2B and cores 3A and 3B are rotatably supported on an inked ribbon cartridge 10 so as to penetrate a front cover 10a of the cartridge 10. A rubber belt 1 is engaged with the feed drive rollers 2A and 2B and the cores 3A and 3B on the outside of the front cover 10a, as shown in FIG. 1. Idle rollers 4A and 4B placed inside the cover 10a are pressed against the feed drive rollers 2A and 2B by means of springs 5A and 5B made of piano wires, respectively, with an inked ribbon 6 pinched therebetween, as shown in FIG. 2, and thereby a ribbon feed mechanism is constructed. The terminal ends of the ribbon 6 are fixedly secured to sleeves 7A and 7B, respectively, which are mounted around the core 3A and 3B via ratchet clutches RC so that rotation in one direction only may be transmitted. Accordingly, upon rotation of the core 3A in the direction indicated by arrow g, the sleeve 7A rotates integrally with the core 3A, but upon rotation in the opposite direction to that indicated by arrow g, the sleeve 7A rotates independently. Likewise, upon rotation of the core 3B in the direction indicated by arrow h, the sleeve 7B rotates integrally with the core 3B, but upon rotation in the opposite direction to that indicated by arrow h, the sleeve 7B rotates independently.

#When the inked ribbon cartridge 10 is loaded in a carrier unit CU (not shown) of a serial printer with the front cover surface 10a having an indication mark e' of "1" placed on the front side, the feed drive roller 2A is engaged with a ribbon drive shaft (shown in FIG. 4 as component 22) in the carrier unit of the serial printer on the back cover surface 10b of the ribbon cartridge 10 (the surface having an indication mark f of "2" imprinted). As a torque in the direction indicated by arrow k is transmitted to the feed drive roller 2A, the rubber belt 1 travels in the direction indicated by solid line arrow m. Accordingly, the core 3A rotates in the direction indicated by arrow g, and the ribbon 6 is pulled in the direction indicated by arrow a and taken up by the sleeve 7A. As the coil diameter of the ribbon 6 being taken up is increased, slip arises between the core 3A and the belt 1, the ribbon 6 is continuously taken up while controlling a take-up tension by means of a tension arm 8A made of a piano wire.

#On the other hand, because the feed drive roller 2B and the core 3B are rotated in the counter-clockwise direction, the sleeve 7B can rotate independently of the rotation of the core 3B in the counter-clockwise direction, and a frictional force is applied to the sleeve 7B for preventing its overrotation by a braking pad BP (provided on the inside of the front cover 10a), whereby the ribbon 6 wound around the sleeve 7B can be payed out under an appropriate tension. When the pay-out operation has reached the terminal end of the ribbon 6, since the terminal end of the ribbon 6 is fixedly secured to the sleeve 7B, a tension arm 8B made of a piano wire is flexed as indicated by a dashed line t in FIG. 2, and hence, movement of a tip end 9B of the tension arm 8B, (or 9A of tension arm 8A) is used for detecting the arrival at the terminal end of the ribbon 6. It is possible to stop the printing operation of the serial printer in response to the actuation of the ribbon end detector switch DS.