US 4,247,210 AGranted

Ribbon feed and lift mechanism for a typewriter

AssigneeInternational Business Machines Corporation

InventorsDonald J. Kacmarcik, Selahattin A. Okcuoglu, Jerry W. Raider

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Abstract

In a daisy wheel or rotary print wheel typewriter, a single motor is employed to accomplish both ribbon lift and feed for typewriter ribbon and correction ribbon loaded in a cartridge assembly. A single motor drive moves the cartridge assembly support about an axis to present the typewriter ribbon or the correction ribbon to the print point at the print line. When the elevation of the cartridge assembly about the axis is such to permit normal typing upon the typewriter ribbon, only the feed ratchet for the ribbon is engaged. Alternatively, when the rotation is greater, for example, for typing on the correction ribbon, the added elevation of the cartridge assembly effects disengagement of the normal ratchet feed for the typewriter ribbon while allowing advancement of the correction ribbon.

Claims25

Dependent claims

In a typewriter having provisions for receiving a typewriter ribbon and a correction ribbon in a cartridge including separate take-up spools;

cartridge support means for oscillating said cartridge and presenting different portions of said ribbon to a print point along a print line and selectively presenting correction ribbon to said print point, the improvement comprising:
separate typewriter ribbon and correction ribbon drives for feeding respectively typewriter ribbon and correction ribbon, said typewriter ribbon drive comprising;
motor means connected to said cartridge support means for oscillating said support means in an arc about an axis substantially parallel to said print line to present during a first segment of the arc, typewriter ribbon opposite the print point, and during a second segment of the arc correction ribbon opposite the print point;
a first reciprocating drive member coupled to said motor means and having a distance of reciprocation proportional to the segment of arc traversed by said support means during its oscillation;
first and second ratchet members respectively coupled to said typewriter ribbon and correction ribbon take-up spools to effect rotation thereof;
pawl means connected to said drive member and including ratchet engaging means for effecting unidirectional rotation of said first ratchet member during the first segment of an arc traversed by said support means without rotation of said second ratchet member, and means for camming said ratchet engaging means away from said first ratchet member while maintaining engagement with said second ratchet member for effecting unidirectional rotation of said second ratchet member only during the second segment of arc traversed by said support means.

3 more elements

A typewriter including a typing platen and a carrier translatable along said platen, said carrier mounting a typing element and including means for receiving a typewriter ribbon and a correction ribbon mated together in overlapping superimposed relation to form a cartridge assembly, including separate take-up spools;

cartridge support means for oscillating said cartridge assembly and presenting different portions of said ribbon to a print point intermediate said typing element and said platen and along a print line and selectively presenting correction ribbon to said print point;
motor means connected to said cartridge support means for oscillating said support means in an arc about an axis substantially parallel to said print line to present during a first segment of the arc, typewriter ribbon opposite the print point, and during a second segment of the arc correction ribbon opposite the print point;
separate typewriter ribbon and correction ribbon drives for feeding respectively typewriter ribbon and correction ribbon during oscillation of said support means, said typewriter ribbon drive comprising;
a first reciprocating drive member coupled to said motor means and having a distance of reciprocation proportional to the segment of arc traversed by said support means during its oscillation;
first and second ratchet members respectively coupled to said typewriter ribbon and correction ribbon take-up spools to effect rotation thereof;
each of said ratchet members including a plurality of circumferentially projecting teeth thereon, the teeth of said second ratchet member having a pitch greater than the pitch of the teeth of said first ratchet member;
pawl means connected to said drive member and including ratchet engaging means for effecting unidirectional rotation of said first ratchet member during the first segment of an arc traversed by said support means and due to the distance of reciprocation of said pawl means being less than the pitch of said second ratchet member, without rotation of said second ratchet member;
said ratchet engaging means effecting unidirectional rotation of said second ratchet member only during the second segment of arc traversed by said support means, one of said teeth of said second ratchet member serving as a cam for camming the pawl means out of engagement with said first ratchet member.

5 more elements

Dependencies are inferred from the claim text.