Surgical stapling apparatus having articulation mechanism

An articulation mechanism comprising:

• a housing;
• a rotatable shaft having an inner end and an outer end, the shaft extending through the housing;
• an articulation member mounted on the outer end of the shaft;
• a rotatable plate, positioned within the housing, and affixed to the inner end of the shaft, the rotatable plate defining a spiral slot;
• a translation member mounted for longitudinal movement within the housing;
• and
• a pin assembly affixed to the translation member and extending into the spiral slot such that rotation of the rotatable plate effects longitudinal movement of the translation member within the housing;
• wherein the plate is a disk having a plurality of teeth;
• and
• wherein the disk includes a recess and the housing includes a spring loaded member engageable within the recess to releasably retain the articulation member in a neutral position.

An articulation mechanism for use with a surgical instrument comprising:

• a rotatable member defining a receptacle and a mechanism cover overlying the receptacle;
• a rotatable shaft having an inner end and an outer end, the shaft extending through the mechanism cover;
• an articulation lever mounted on the outer end of the shaft;
• a rotatable disk, positioned within the receptacle, and affixed to the inner end of the shaft, the rotatable disk defining a spiral slot;
• a translation member mounted for longitudinal movement within the rotatable member;
• and
• a pin assembly affixed to the translation member and extending into the spiral slot such that rotation of the articulation lever effects longitudinal movement of the translation member within the rotatable member;
• wherein the spiral slot defines an Archimedes spiral such that uniform rotation of the rotatable disk effects uniform longitudinal translation of the translation member through the rotatable member.