Patent ID: 7527486

Claim:
A pneumatic surgical motor( 50 ) having a housing ( 30 ), a sleeve ( 40 ) made from a plastic material and being substantially coextensive and contiguous with said housing ( 30 ) surrounding said housing ( 30 ) and being sufficiently small in diameter to serve as a handle for the surgeon, said housing having a plurality of serrations formed on the periphery thereof and extending axially and defining a handle for the operator, the apex of the serrations engaging the inner surface of said housing ( 30 ) and the valley portion defining an air gap acting as an insulator for said sleeve ( 40 ), and being sufficiently small in diameter to accommodate a cylindrical handle for the surgeon to grab to use said motor ( 50 ), a vane motor ( 5 3 )including a spindle (I) being made from a non-magnetic stainless steel material and being rotary supported in said housing ( 30 ), said spindle ( 1 ) being supported by bearings ( 5 ) and attachment mechanism ( 52 ) affixed to said housing ( 30 ) for receiving surgical tools being powered by said vane motor ( 53 ), passageways ( 58 , 62 ) in said housing ( 30 ) for leading pressurized air into said housing ( 30 ) and into said vane motor ( 53 ) for rotating said spindle ( 1 ), and discharge aperture ( 55 ) in said vane motor ( 53 )for leading spent air out of said housing ( 30 ), and a portion of said air passing over said bearings ( 5 ) for cooling said bearings ( 5 ) before being admitted into said vane motor ( 53 ), a cylinder ( 3 ), said spindle ( 1 ) being rotary supported in said cylinder ( 3 ), said spindle ( 1 ) having diametrically opposing stub shafts ( 61 , 63 ) being supported by bearings ( 5 ), said spindle having an outer surface ( 91 ) and said cylinder having an inner surface ( 93 ), said spindle ( 1 ) and said cylinder ( 2 ) being eccentrically mounted so that the spindle ( 1 ) comes into contact with the cylinder ( 3 ) at the pinch point defining a sealing area, means for increasing the sealing area by undercutting said inner surface ( 93 ) of said cylinder to contour said inner surface ( 93 ) for redefining said pinch point into a crescent shaped seal.