Apparatus And Method For A High Speed Rotation-To-Rotation Oscillation Converter For Surgical Use

A converter for use in a high speed oscillating surgical burring device comprising:

• an output shaft;
• a secondary drive rotor coupled to the output shaft, the secondary drive rotor having a spiral slot defined therethrough and being arranged and configured with a size and mass to minimize its angular momentum;
• a drive pin being disposed through the spiral slot, so that the secondary drive rotor rotationally oscillates as the drive pin longitudinally reciprocates;
• a stationary guide having a linear slot defined therethrough through which the drive pin is disposed to maintain the drive pin in a fixed plane of oscillatory linear motion;
• and
• a cam follower coupled to the drive pin;
• a primary drive rotor having a cylindrical bore;
• a pair of elliptical intersecting grooves defined in the cylindrical bore, the cam follower engaging the pair of elliptical grooves so that the drive pin is longitudinally reciprocated within the primary drive rotor as the primary drive rotor unidirectionally rotates;
• and
• an input shaft coupled to the primary drive rotor and to which input shaft a unidirectional rotational force is applied.

A method of providing oscillating rotational motion to surgical burring device comprising:

• unidirectionally rotating an input shaft;
• unidirectionally rotating a primary drive rotor by the input shaft;
• transforming the unidirectional rotation of the primary drive rotor into linearly reciprocating motion of a reciprocating component which is arranged and configured with a size and mass to minimize its linear momentum;
• transforming the linearly reciprocating motion of the reciprocating component into bidirectional rotational oscillation of a secondary drive rotor, which is arranged and configured with a size and mass to minimize its angular momentum;
• and
• rotationally oscillating an output shaft coupled to the secondary drive rotor.