Ribbon shift assembly

Claim 1

In a typewriter having a support frame, a ribbon-lift guide assembly including lift arms for supporting a typewriter ribbon which is provided with upper and lower printing levels, means pivotally supporting said guide assembly for vertical movement to present a selected printing level on the ribbon for typing, a cam, cam follower means responsive to movement of the cam in each printing cycle to undergo vertical movement, an extension member carried by the lift arms selectively engageable with the cam follower means in a first position of the cam follower means to transmit up and down movement of the cam follower means to the lift arms to establish a first printing level of the ribbon and in a second position permitting free independent movement of the cam follower means with respect to the lift arms to establish a second printing level on the ribbon, the combination therewith comprising: an elongated substantially rigid and rotatable shift bail traversing substantially the width of said typewriter and journaled for rotation at opposite ends on said support frame for extEnsion across the typewriter in a direction perpendicular to the lift arms including an axially offset portion between said opposite ends selectively movable in a direction normal to its length upon rotative movement of the shift bail so as to be rotated toward and away from the cam follower means in response to rotation of said bail in advancing the cam follower means between the first and second positions, a draw cable secured by connecting means to the axially offset portion and extending between the axially offset portion on said shift bail and the cam follower means and operative to advance said cam follower means to one of the first and second positions in response to actuation and rotation of the axially offset portion of said shift bail toward the cam follower means and to advance said cam follower means to the other of the first and second positions in response to rotation of the axially offset portion away from said cam follower means, actuating means operatively connected to said shift bail and being selectively activated for rotation of the axially offset portion about the axis of said shift bail in advancing the axially offset portion toward and away from said cam follower means, and return means associated with said shift bail and operative to return the cam follower means to the other of the first and second positions when said actuating means is not activated.