US 7,036,408 B2 · Lenslathe with vibration cancelling arrangement

Abstract

A method and apparatus for substantially nullifying vibration and deflection in a single point lens turning lathe having a rapidly reciprocating lens cutting tool and shuttle assembly. The apparatus includes three or more tool shuttles of similar mass mounted for reciprocating movement along respective generally parallel shuttle paths. The shuttles are reciprocally moveable by respective actuators along their respective shuttle paths. The shuttle and tool assemblies are moved by their respective actuators in opposite directions at a rate which causes forces generated by shuttle and tool assemblies moving in one direction to cancel forces arising from the shuttle and tool assembly movement in the opposite direction. Should an odd number of shuttle and tool assemblies be used, the amount of force generated by the mass moving in one direction may be compensated by having a different rate of movement, and hence a different stroke length from the mass moving in the opposite direction.

Claims19

Dependent claims

A lens cutting lathe comprising:

a base;
a lens support mounted to said base for supporting said lens and spinning said lens about a lens rotational axis, said lens support being transversely moveable relative to said lens rotational axis;
a plurality of shuttles for mounting respective cutting tools mounted to said base in side by side arrangement far movement toward and away from said lens along respective generally parallel shuttle paths;
said plurality of shuttles being reciprocally movable by respectively actuators mounted to said base, said actuators being arranged to move some of said plurality of shuttles in a direction opposite to a remainder of said plurality of shuttles;
and,
said plurality of shuttles being of similar mass and disposed and moved in a manner to maintain a generally fixed center of mass whereby movement of said some of said shuttles in a given direction substantially cancels linear forces imposed on said base by movement or said remainder of said shuttles in the opposite direction.

3 more elements

A method of turning a non-rotationally symmetrical lens on a lens turning lathe having a lens support and at least three lens cutting tools, said method comprising the steps of:

(i) mounting a lens blank to a lens support assembly;
(ii) rotating said lens blank with said lens support assembly about a lens rotational axis;
(iii) pressing one of said at least three cutting tools against said lens blank;
(iv) moving said lens blank with said lens support assembly in a direction transverse to said lens rotational axis;
(v) reciprocally moving said one of said at least three lens cutting tools along a first tool path at a reciprocal frequency corresponding to the rotational frequency of said lens blank to produce said non-rotationally symmetrical surface;
and,
(vi) reciprocally moving remaining of said at least three lens cutting tools along respective tool paths generally parallel to said first tool path at said reciprocal frequency in a direction and at a rate which counters and substantially nullifies linear forces imposed on said lathe by said one tool in step (v) without imparting a rocking movement on said lathe.

4 more elements

Dependencies are inferred from the claim text.

Lenslathe with vibration cancelling arrangement

Life of this patent

Lenslathe with vibration cancelling arrangement

Life of this patent

Abstract

Claims19