Relative Translation System

Abstract

A relative translation assembly operable with a drive mechanism. The relative translation assembly can have a fixed support member, a translatable member supported by the fixed support member, and a translation guide portion to facilitate translation of the translatable member relative to the fixed support member. The translation guide portion can have a fixed translation member and a movable translation member. The movable translation member can be configured to maintain preload on the fixed and movable translation members and accommodate thermal expansion. The drive mechanism can be configured to cause translation of the translatable member relative to the fixed support member.

What is claimed is: 
     
         1 . A drive mechanism, comprising:
 a drive shaft having a threaded portion;   a bearing to facilitate rotation of the drive shaft, the bearing being configured to support the drive shaft and interface with a first structure; and   a drive member engaged with the threaded portion of the drive shaft and configured to be fixed to a second structure to facilitate translation relative to the threaded portion upon rotation of the drive shaft,   wherein an angle of misalignment of the bearing compensates for drive shaft rotational misalignment, and   wherein a position of the drive member is adjustable upon assembly to compensate for drive axis translational misalignment.   
     
     
         2 . The drive mechanism of  claim 1 , further comprising a backlash compensation mechanism. 
     
     
         3 . The drive mechanism of  claim 1 , further comprising:
 a second bearing configured to interface with the first structure proximate the first bearing, the second bearing having clearance for the drive shaft extending therethrough; and   a spring configured to act on an inner race of the second bearing to facilitate preload of the first and second bearings.   
     
     
         4 . The drive mechanism of  claim 1 , wherein the first structure comprises a fixed support of a relative translation system, and wherein the second structure comprises a translatable member of the relative translation system.