Abstract: A print unit provided with one or a multi-serial heads having a plurality of print pins widely arranged in a direction of the feeding of paper and is provided laterally movably on a guide shaft. A cassette holder having a plurality of monochromatic ribbon cassettes that are juxtaposed and received therein is arranged in parallel with and close to the moving path of the print unit. A suitable one of the monochromatic ribbon cassettes is transferred, in response to a control signal, from the cassette holder to the print unit, and from the print unit to the cassette holder.

Abstract: A motion transforming mechanism which comprises a sliding member, a rack lever supported rotatably on the sliding member and engageable with a driving gear, a trigger lever supported rotatably on said sliding member and engaged with said rack lever and a fixed pin engageable with the rack lever so that the rotation of the driving gear may be positively and accurately transformed to a linear motion of a fixed stroke, the sliding member being utilized to intermittently rotate a ratchet wheel.

Abstract: The line printer comprises a main frame; a type-carrying drum mounted in said main frame for selective rotation and a plurality of rows of the type supported in the periphery of said drum; a plurality of typewriting hammers pivoted to said main frame adjacent to said drum for effecting a typewriting operation in cooperation with the drum; a subframe assembly adjustably secured to said main frame, said subframe assembly comprising a subframe adjustably secured to said main frame, a plurality of selector levers pivoted to the subframe by means of a common lever shaft in association with said hammers, respectively, a plurality of drive levers pivoted to said selector levers respectively, said drive levers being so spring-loaded that when said selector levers are pivoted in one direction against spring force, the drive levers engage said cam shaft to be operated thereby so as to engage said hammers to cause the hammers to strike against said drum for effecting a typewriting operation in cooperation with the drum,