Character selection for single element printer

In a selection mechanism for a single element printer having a single print element, the improvement comprising:

• (a) an operating link connected with said print element for rotating said print element, said operating link having first and second input portions;
• (b) a modifying member supporting said operating link for pivotal motion about said first input portion and mounted for shifting movement to shift said first input portion between a pair of locations, said modifying member having a camming slot formed therein;
• (c) a movable member engaged in said camming slot and disposed to be moved from an initial position in either direction perpendicular to the shifting direction of said first input portion thereby positioning said first input portion to either of a pair of character selection positions;
• and
• (d) means connected to said operating link at said second input portion for positioning said link to any of a predetermined plurality of pivotal positions relative to said first input portion thereof.

In a selection mechanism for a single element printer having a single print element, the mechanism comprising a multichannel barrel cam supported for rotation about and translation along its axis, a plurality of fixed selection pins each selectively engageable with one of said channels, and a cam follower to transmit the axial translation of said cam, the improvement comprising:

• (a) an operating link having at an end thereof an output portion connected to said print element for rotating said print element, said link further having first and second input portions;
• (b) a modifying member supporting said operating link for pivotal motion about said first input portion;
• (c) input means for positioning said modifying member to position said first input portion of said operating link to any of a predetermined plurality of character selection positions;
• (d) means for connecting said cam follower to said operating link at said second input portion thereof whereby when said barrel cam is axially translated, said operating link is positioned to any of a predetermined plurality of pivotal positions relative to said first input portion thereof;
• and
• (e) a locking member cooperable with said modifying member for locking said first input portion of said operating link in position after said operating link is positioned by said input means and said barrel cam.

In a selection mechanism for a single element printer having a single print element, the improvement comprising:

• (a) an operating link connected to said print element for rotating said print element, said operating link having first and second input portions;
• (b) a modifying member supporting said operating link for pivotal motion about said first input portion, said modifying member having a camming slot formed therein;
• (c) a pivotable lever having a free end disposed for engagement in said camming slot of said modifying member;
• (d) selectively operable means for selectively pivoting said lever in a first or second direction to position, through camming engagement of said lever in said slot of said modifying member, said first input portion of said operating link to either of a pair of positions;
• and
• (e) means connected to said operating link at said second input portion for positioning said link to any of a predetermined plurality of pivotal positions relative to said first input portion thereof.

In a printer having a movable print carrier, a print element carried by said carrier for rotation to present different characters to a print position, a plurality of character keys, a case shift key, a print shaft responsive to depression of any character key to rotate itself one cycle about the axis thereof, and a case shift shaft responsive to each depression and release of the case shift key to rotate said case shift shaft one cycle about the axis thereof, the improvement comprising:

• (a) a differential mechanism mounted on said carrier and connected to said print element for rotating said print element, said mechanism including a link having an output and two input portions thereon;
• (b) a case shift cam mounted on said carrier for rotation by said case shift shaft, said case shift cam having two operative positions to which said case shift cam is brought alternately upon each cycle of rotation of said case shift shaft;
• (c) a cam follower engageable with said case shift cam to shift one of said input portions of said link between two positions corresponding to said two operative positions of said cam for producing a complete one-half revolution of said print element to effect a case shift;
• and
• (d) character selection means mounted on said carrier for positioning the other of said input portions of said link to any of a predetermined plurality of positions in response to depression of a character key wherein a corresponding character is positioned in said print position.

In a single element printer having a carrier, a rod fixed on said carrier, a rocker mounted for rocking motion about said rod, a single print element mounted for rotating and tilting motion on and relative to said rocker, and means for driving said rocker to rock about said rod to effect a printing operation, the improvement comprising:

• (a) a racked member having a circumferential rack formed thereon and mounted for slidable axial movement on said rod;
• (b) a sector gear pivotally mounted on said rocker and disposed in engagement with said circumferential rack of said racked member, said sector gear being pivoted in response to the axial movement of said racked member on said rod, said sector gear being pivotable in a plane which includes said rod therein to maintain constant engagement with said racked member even when said rocker is rocked;
• (c) a link connecting said sector gear with said print element for imparting the pivotal motion of said sector gear to said print element thereby tilting said print element;
• and
• (d) input means for axially positioning said racked member on said rod.