Torque transmitting ball joint driver having a rigid fixation mechanism

Abstract

An articulating driver having a ball-in-socket joint. The driver may include a driver tip having a spherical head, a retention cap having a domed surface to mate with the spherical head, an input shaft, a spring disposed in an end of the input shaft and in a recess of the retention cap opposite that of the domed surface, and a housing that receives the input shaft, the spring, the retention cap and the spherical head. The housing may have a tapered end to positionally retain the spherical head therein. In another aspect, the driver may include a driver tip coupled to the input shaft that includes an interface to engage a screw. A bushing may engage the driver tip at one end and receive the screw at the other end to retain the screw within the driver.

What is claimed: 
     
         1 . A driver having a ball-in-socket joint, comprising:
 a driver tip having a spherical head;   a retention cap having a domed surface to mate with the spherical head;   an input shaft;   a spring disposed in an end of the input shaft and in a recess of the retention cap opposite that of the domed surface; and   a housing that receives the input shaft, the spring, the retention cap and the spherical head,   wherein the housing has a tapered end to positionally retain the spherical head therein.   
     
     
         2 . The driver of  claim 1 , wherein the spherical head has a plurality of grooves defined in a surface thereof, wherein the housing defines a plurality of holes, and wherein each of the holes receives a pin that passes through the housing and is received within a respective groove of the spherical head. 
     
     
         3 . The driver of  claim 2 , wherein torque applied at the input shaft is transmitted to the housing and to the driver tip by action of the pins within the grooves of the spherical head. 
     
     
         4 . The driver of  claim 2 , wherein the plurality grooves have a shape to provide for up to 50° of angulation of the driver tip with respect to the input shaft over a 360° rotation of the input shaft. 
     
     
         5 . The driver of  claim 4 , wherein the grooves have a generally ovular shape and a W-shape cross-section within spherical head. 
     
     
         6 . The driver of  claim 2 , wherein the grooves are positioned within spherical head at offsets of approximately 120°. 
     
     
         7 . The driver of  claim 2 , wherein the grooves extend over an approximately 120° arc across a face of the spherical head. 
     
     
         8 . The driver of  claim 1 , wherein the spring exerts a force on the retention cap to positionally retain the spherical head within the housing. 
     
     
         9 . A ball-in-socket joint, comprising:
 an input shaft;   an output shaft having a spherical head, the spherical head having a plurality of grooves defined therein;   a retention cap having a domed surface to mate with the spherical head;   a spring disposed in an end of the input shaft and in a recess of the retention cap opposite that of the domed surface; and   a housing the defines a plurality of holes, the housing receiving the input shaft, the spring, the retention cap and the spherical head,   wherein the housing positionally retains the spherical head therein, wherein each of the holes receives a pin that passes through the housing and is received within a respective groove of the spherical head.   
     
     
         10 . The ball-in-socket joint of  claim 9 , wherein torque applied at the input shaft is transmitted to the housing and to a driver tip associated with the output shaft by action of the pins within the grooves of the spherical head. 
     
     
         11 . The ball-in-socket joint of  claim 9 , the housing further comprising a tapered end, wherein the domed surface and tapered end each have a radius of curvature that is approximately equal to a radius of the spherical head, and wherein the tapered end and the domed surface positionally retain the spherical head within the housing. 
     
     
         12 . A driver, comprising:
 an input shaft adapted to transmit torque;   a driver tip coupled to the input shaft, the driver tip including an interface defined at an end thereof adapted to engage a screw; and   a bushing that engages the driver tip at one end and receives the screw at the other end,   wherein the screw is received within the bushing and engages the interface, and   wherein the input shaft is adapted to apply torque to the screw through the interface and to apply torque to the bushing by the engagement of the bushing with the driver tip.   
     
     
         13 . The driver of  claim 12 , wherein the bushing includes inner threads disposed at a distal end thereof and inner threads disposed at a proximal end thereof. 
     
     
         14 . The driver of  claim 13 , wherein the driver tip further comprises a threaded region that engages the inner threads disposed at the proximal end of the bushing. 
     
     
         15 . The driver of  claim 14 , wherein the inner threads at the distal end of the bushing are adapted to pass over the threaded region of the driver tip. 
     
     
         16 . The driver of  claim 13 , wherein the screw further comprise an outer threaded portion on an external surface of a head of the screw, the outer threaded portion adapted to engage the inner threads disposed at the distal end of the bushing. 
     
     
         17 . The driver of  claim 12 , the bushing further comprising a stop region, wherein the stop region cooperates with an aiming device to hold the bushing within the aiming device as torque is transmitted to the screw and the bushing. 
     
     
         18 . The driver of  claim 17 , wherein when torque continues to be applied to the screw after the bushing is held within the aiming device, the screw releases from the bushing. 
     
     
         19 . The driver of  claim 17 , wherein the stop region is formed having a zig-zag shaped edge, and wherein the forward progress of the bushing is halted by an interaction of a pin of the aiming device with a vertex formed by the zig-zag shaped edge. 
     
     
         20 . The driver of  claim 17 , wherein the stop region comprises a plurality of lobes that extend outward from a center of the bushing, and wherein the forward progress of the bushing is halted by an interaction of a plurality of complementary lobes that extend inwardly from a center of an aiming hole of the aiming device. 
     
     
         21 . A driver having a double-wobble joint, comprising:
 an input shaft having a first spherical head that includes a distal ball;   a driver tip having a second spherical head that includes a proximal socket that is adapted to receive the distal ball;   a housing that receives the input shaft and the driver tip; and   a spring disposed between a first washer and a second washer in the housing, the first washer being disposed between a proximal end of the spring and the first spherical head, and the second washer being disposed between a distal end of the spring and the second spherical head, the spring providing an urging force on the first washer and the second washer within to positionally retain the first spherical head and the second spherical head within the housing.   
     
     
         22 . The driver of  claim 21 , wherein the first spherical head defines a first cavity and the second spherical head defines a second cavity, wherein a first pin is disposed within the first cavity to secure the first spherical head to the housing, and wherein a second pin is disposed within the second cavity to secure the second spherical head to the housing. 
     
     
         23 . The driver of  claim 22 , wherein the cavity is formed having a generally bow-tie shape. 
     
     
         24 . The driver of  claim 22 , wherein the first cavity extends through first spherical head to form an upper opening and a lower opening on a surface of the first spherical head, and wherein the second cavity extends through second spherical head to form an upper opening and a lower opening on a surface of the second spherical head. 
     
     
         25 . The driver of  claim 24 , wherein the upper opening and the lower of the first spherical head and the upper opening and the lower of the second spherical head each extend across an arc of approximately a 44° across a surface of the first spherical head and the second spherical head, respectively. 
     
     
         26 . The driver of  claim 22 , wherein torque applied at the input shaft is transmitted to the housing and to the driver tip by action of the first pin within the first cavity and the second pin within the second cavity. 
     
     
         27 . The driver of  claim 22 , wherein the first cavity and the second cavity provide approximately 44° of angulation of the driver tip with respect to the input shaft over a 360° rotation of the input shaft. 
     
     
         28 . The driver of  claim 27 , wherein the housing defines chamfered edges at a proximal opening and a distal opening, wherein the driver tip and the input shaft each define a base that is adapted to contact the chamfered edges to limit the angulation of the driver. 
     
     
         29 . The driver of  claim 28 , wherein the limit of the angulation is approximately 40°. 
     
     
         30 . The driver of  claim 21 , wherein an interaction of the distal ball within the socket provides for a constant velocity in the double-wobble joint.