Surgical Stapling Apparatus Having Articulation Mechanism

Abstract

An articulation mechanism for use with a surgical apparatus having an articulating tool assembly is described. The articulation mechanism includes a rotatable shaft which is fixedly secured to a disk defining a spiral groove or slot. A linearly movable translation member is provided and includes a pin which is received within the spiral groove such that rotation of the disk effects linear translation of the translation member. The configuration of the spiral groove can be selected to provide any desired ratio of angular rotation of the disk to linear advancement of the translation member. As such, the configuration of the spiral slot can be selected to provide a uniform rate of articulation of the tool assembly of the surgical apparatus or a variable rate of articulation.

1 . 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 substantially flat rotatable plate, positioned within the housing and fixedly connected 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.   
     
     
         2 . The articulation mechanism as recited in  claim 1 , wherein the spiral slot is formed in the shape of an Archimedes spiral. 
     
     
         3 . The articulation mechanism as recited in  claim 1 , wherein the spiral slot is configured to provide reduced longitudinal movement of the translation member per degree of angular rotation of the rotatable shaft near a neutral position of the articulation member than further from the neutral position of the articulation member. 
     
     
         4 . The articulation mechanism as recited in  claim 1 , wherein the plate is a disk having a plurality of teeth. 
     
     
         5 . The articulation mechanism as recited in  claim 1 , wherein the translation member includes structure for engagement with articulation structure of a surgical instrument. 
     
     
         6 . The articulation mechanism as recited in  claim 1 , wherein the housing is a rotatable member configured for use with a surgical instrument. 
     
     
         7 . The articulation member as recited in  claim 6 , wherein the housing includes a receptacle configured to receive the disk. 
     
     
         8 . The articulation member as recited in  claim 7 , wherein the housing includes a mechanism cover, affixed to the receptacle, and supporting the rotatable shaft. 
     
     
         9 . An articulation mechanism for use with a surgical instrument comprising:
 a member defining a receptacle and a cover overlying the receptacle;   a rotatable shaft having an inner end and an outer end, the shaft extending through the cover;   an articulation lever mounted on the outer end of the shaft;   a rotatable disk, positioned within the receptacle and fixedly connected to the inner end of the shaft, the rotatable disk defining a spiral slot;   a translation member mounted for longitudinal movement within the 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 member.   
     
     
         10 . The articulation mechanism as recited in  claim 9 , wherein the spiral slot is configured to provide reduced longitudinal movement of the translation member per degree of angular rotation of the rotatable shaft near a neutral position of the articulation lever than further from the neutral position of the articulation member. 
     
     
         11 . The articulation mechanism as recited in  claim 9 , further comprising indexing elements formed on the rotatable disk and provided within the receptacle. 
     
     
         12 . The articulation mechanism as recited in  claim 11 , wherein the indexing elements include a plurality of teeth on an outer periphery of the rotatable disk. 
     
     
         13 . The articulation mechanism as recited in  claim 12 , wherein the indexing elements further include a spring loaded slide supported on the rotatable member.