Anti-backlash differential

Claim 1

A SELF-ADJUSTING, SELF-COMPENSATING ANTI-BACKLASH DIFFERENTIAL OF MINIATURE SIZE AND PRECISION CONSTRUCTION COMPRISING: A ROTATABLE SHAFT; A PAIR OF BEVEL GEARS LOOSELY MOUNTED ON SAID SHAFT FOR ANGULAR DISPLACEMENT THEREABOUT, SAID GEARS BEING RESTRAINED AGAINST AXIAL MOVEMENT RELATIVE TO SAID SHAFT, SAID GEARS BEING DISPOSED IN SPACED RELATION TO EACH OTHER; A SECOND SHAFT FIXEDLY CARRIED BY SAID ROTATABLE SHAFT AND INTERMEDIATE TO SAID PAIR OF BEVEL GEARS, SAID FIRST AND SECOND SHAFTS BEING DISPOSED AT SUBSTANTIALLY RIGHT ANGLES TO EACH OTHER; A BEVEL PINION ROTATABLY DISPOSED ON SAID SECOND SHAFT AND ADAPTED TO MESH WITH BOTH OF SAID PAIR OF BEVEL GEARS; EACH OF SAID BEVEL GEARS BEING FORMED OF FIRST AND SECOND CLOSELY NESTED SECTIONS COAXIALLY DISPOSED IN TANDEM ON SAID FIRST SHAFT, SAID FIRST AND SECOND SECTIONS OF EACH GEAR HAVING A COMMON COPLANAR BEVELLED FACE WITH GEAR TEETH FORMED ON EACH OF SAID RESPECTIVE SECTIONS, SAID TEETH BEING IN REGISTRY IN THE ASSEMBLED CONDITION TO DEFINE A UNITARY BEVEL GEAR CONFIGURATION, SAID FIRST AND SECOND SECTION OF EACH GEAR BEING ANGULARLY DISPLACEABLE RELATIVE TO EACH OTHER TO THEREBY DISPLACE THE TEETH OF SAID FIRST SECTION OUT OF REGISTRY WITH THE TEETH OF SAID SECOND SECTION; A SPRING MEMBER MOUNTED IN SPACED RELATION BETWEEN SAID FIRST AND SECOND SECTIONS, ONE TERMINAL OF SAID SPRING MEMBER BEING SECURED TO SAID FIRST SECTION, THE SECOND TERMINAL OF SAID SPRING MEMBER BEING TERMINALS BEING ANGULARLY SPACED FROM EACH OTHER ON A DIAMETER SMALLER THAN THE OUTSIDE DIAMETER OF SAID NESTED BEVEL GEARS, SAID SPRING MEMBER IN THE UNSTRESSED CONDITION BEING ADAPTED TO MAINTAIN THE TEETH OF SAID SECOND SECTION; SAID DIFFERENTIAL IN THE ASSEMBLED CONDITION HAVING SAID BEVEL PINION IN MESHED RELATION WITH SAID FIRST AND SECOND SECTIONS TO THEREBY MAINTAIN SAID TEETH IN SAID FIRST AND SECOND SECTIONS IN REGISTRY AND TO THEREBY PRELOAD SAID SPRING MEMBER, SAID PRELOADING BEING ADAPTED TO URGE SAID TEETH PORTIONS OF SAID FIRST AND SECOND SECTIONS INTO RESPECTIVE CLOCKWISE AND COUNTER CLOCKWISE ANGULAR ABUTMENT WITH MATING ADJACENT TEETH OF SAID PINION TO THEREBY MINIMIZE BLACKLASH.