Tissue Retractor

Abstract

A tissue retractor device for retracting tissue is disclosed. The device includes a base connected to a plurality of blades distributed around the base. Each of the blades is outwardly movable from the base. A pusher is engaged to the base. The pusher is movable in a longitudinal direction to move the blades to angularly displace each of the blades from a respective closed position to an open position. At least one biasing device is engaged with the base that biases the respective ones of the blades toward a closed position. The closed position is where the blades are relatively close together with respect to the open position.

1 . A tissue retractor device for retracting tissue, said device comprising:
 a base connected to a plurality of blades distributed around said base, each of said blades being outwardly movable from the base;   a pusher engaged to said base, said pusher movable in a longitudinal direction to move said blades to angularly displace each of said blades from a respective closed position to an open position;   at least one biasing device engaged with the base that biases the respective ones of the blades toward a closed position, wherein said closed position is where said blades are relatively close together with respect to the open position;   wherein each of the blades includes a respective one of a plurality of shoulders, wherein each of the shoulders has a surface extending substantially perpendicular and outward from an axis of the base when the blades are in a closed position, wherein the axis is parallel to a movement direction of the pusher;   wherein the base includes at least one surface substantially perpendicular to the axis;   wherein the biasing device is positioned between the surface of the base and the surface of the shoulders such that the biasing device is compressed in a direction substantially parallel to the axis when the blades are moved toward the open position from the closed position.   
     
     
         2 . The device of  claim 1 , wherein the pusher threadably engages said base such that rotation of the pusher moves the pusher in said longitudinal direction. 
     
     
         3 . The device of  claim 1 , wherein:
 the biasing device is at least one elastic device positioned between a portion of the blades and the base; and   the blades compress the elastic device when the blades move toward the open position to bias the blades toward the closed position.   
     
     
         4 . The device of  claim 3 ,
 wherein the elastic device is a plurality of springs, wherein each of the springs is positioned between the surface of the base and a respective ones of the surfaces of the shoulders to bias the blades toward the closed position.   
     
     
         5 . The device of  claim 3 , wherein:
 the elastic device comprises an O-ring circumferentially positioned around a surface of the base;   the O-ring is positioned between the surfaces of the shoulders and the surface of the base such that movement of the blades toward the open position moves the shoulders against the O-ring to bias the blades toward the closed position.   
     
     
         6 . The device of  claim 4 , further comprising:
 a plurality of apertures in the base, wherein the at least one surface of the base is a plurality of surfaces at a bottom portion of respective ones of the apertures;   wherein each of the springs residing in a respective one of the apertures;   wherein an axial end of each of the springs abuts a respective ones of the shoulders;   wherein movement of the blades toward the open position compresses each of the springs between the bottom portion of each aperture and respective one of the surfaces of the shoulders to bias each of the blades toward the closed position.   
     
     
         7 . The device of  claim 6 , wherein a length of each of the springs is sized such that each shoulder abuts the base before fully compressing the spring when the blades are moved toward the open position. 
     
     
         8 . The device of  claim 6 , wherein a length of each of the springs is sized such that each of the springs fully compresses prior to the shoulders abutting the base when the blades are moved toward the open position. 
     
     
         9 . A tissue retractor device for retracting tissue, said device comprising:
 a base connected to a plurality of blades distributed around said base, each of said blades being outwardly movable from the base;   a pusher engaged to said base, said pusher movable in a longitudinal direction to move said blades to angularly displace each of said blades from a respective closed position to an open position;   at least one biasing device engaged with the base that biases the respective ones of the blades toward a closed position, wherein said closed position is where said blades are relatively close together with respect to the open position;   each of the blades is constructed with an elastic material and is the biasing device, wherein the material blades biases the blades toward the closed position   
     
     
         10 - 17 . (canceled)