Carrier positioning and tabulation apparatus

Claim 1

Escapement and tabulation apparatus in a single print element typewriting machine having a carrier impelled to advance selectively for characters and spaces to be printed and for tabulation, said apparatus comprising: means for advancing said carrier; a rotatable lead screw for controlling said advance of said carrier for both said characters and spaces to be printed and tabulation, said advance being determined by rotation of said rotatable lead screw; means associated with said rotatable lead screw for stopping rotation of said rotatable lead screw and said advance of said carrier; means associated with said rotatable lead screw for defining multiples of increments of advance of said carrier; rotatable tabulation means having settable pins for defining approaches to tabulation positions and rotatable synchronously with said advance of said carrier by said means for advancing said carrier; means for setting at least one of said settable pins; a first sensing means associated with said rotatable tabulation means operative to provide a first signal upon sensing a set one of said settable pins; and a second sensing means associated with said rotatable lead screw for sensing a tabulation position defined by said first signal and a multiple of said increments and operative to provide a second signal for operating said stopping means during tabulation for stopping said advance of said carrier at said tabulation position after the occurrence of said first signal and upon the sensing of a multiple of said increments.