Rotary oscillating surgical tool
A surgical tool with a housing, and a cutter support shaft operably connected to a motor to effect rotation of the shaft with a drive transmission configured between the motor and the shaft to effect oscillating rotary movement of the shaft and cutter is disclosed.
1. An oscillating rotary surgical tool including;
a housing forming a handle;
a motor mounted in the housing, said motor having a rotary output first shaft;
a second shaft rotatably carried by the housing and having a cutter positioned at a distal end of the shaft;
a transmission mounted in the housing and operably associated with the motor and coupling the first shaft to the second shaft, said transmission having a first section and a second section with the first section including a planetary gear set, said planetary gear set including a ring gear fixed against rotation relative to the housing and including a first pinion gear coupled to the motor to effect its movement within the ring gear revolving about the first shaft, said first section also including a driver mounted to the first pinion gear and movable therewith, said second section including a follower operably associated with the driver, said follower being pivotally mounted in the housing and movable in an oscillating manner in response to movement of the driver effected by rotation of the first shaft, said follower including a drive gear also movable in a rotary oscillating manner, said drive gear being in engagement with a driven gear member secured to said second shaft, whereby said second shaft is moved in a rotary oscillating manner by rotation of the first shaft.
2. The surgical tool of claim 1 wherein the gear ratio of the ring gear to the first pinion gear being 2:1.
3. The surgical tool of claim 2 wherein the first pinion gear being coupled to the first shaft with a crank arm.
4. The surgical tool of claim 3 wherein the follower is operable for movement in reciprocal rotary oscillation about an axle on which it is pivotally mounted.
5. The surgical tool of claim 4 wherein the follower including an elongate slot with a portion of the driver received therein.
6. The surgical tool of claim 4 wherein the drive gear being a sector gear moveable in an arc about the axle in reciprocal rotary oscillation.
7. The surgical tool of claim 6 wherein the second shaft having the driven gear member secured thereto and coupled to the sector gear, whereby reciprocal rotary oscillation of the sector gear effects reciprocal rotary oscillation of the driven gear member and the second shaft.
8. The surgical tool of claim 7 wherein the second shaft including the cutter on a distal end thereof and movable in reciprocal rotary oscillation with the second shaft.
9. The surgical tool of claim 8 wherein the motor being an electric motor.
10. The surgical tool of claim 9 including a power source carried in the housing, said power source including at least one battery.