Anti-backlash device for a motorized optical component positioning stage

An anti-backlash device in combination with a positioning stage having a workpiece mounting table slideably disposed on rails, a motor assembly drivingly connected to a threaded rod wherein rotation of said motor affects lateral movement of said table along the rails;

• the anti-backlash device comprising,
• a tubular member having a first end and a second end separated by a plurality of resilient bridges, extending between said first and second ends, separated by a like plurality of slots also extending between said first and second ends,
• the first and second ends having an outer diameter to facilitate a press fit engagement within a bore in said table and the resilient bridges having an incurvate compressive bias providing a variable diameter decreasing to a central portion of the tubular member;
• the bridges together define, on an inner surface thereof, an interrupted female thread, for a biased, resilient engagement with the threaded rod to effectuate a resiliently biased substantially zero clearance engagement of the female thread with the thread of the rod;
• the bridges together define, on an inner surface thereof, an interrupted female thread, for a biased, resilient engagement with the threaded rod to effectuate a resiliently biased substantially zero clearance engagement of the female thread with the thread of the rod;
• the female thread of the bridges being located only on a substantially central portion of the bridge.