Abstract: The present invention provides an improvement for use in a machine tool having a spindle (51) mounted in a body opening (30) for axial and rotative movement relative to a body (31). The improvement includes a bearing assembly (25) that permits spindles (S1, S2, S3, . . . ) to be quickly exchanged while obviating the need to recenter a replacement spindle with respect to the opening after the original spindle has been initially center therein. The improved bearing assembly (25) broadly includes: a ferrous tubular sleeve (29) mounted in the body opening, the sleeve having an outer surface (40) arranged to face toward a portion (31) of the body that surrounds the opening and having an inner surface (36, 39) arranged to face toward a penetrant portion of the spindle; and a tubular bearing (46) arranged within the sleeve, the tubular bearing having an outer surface (51) arranged to face the sleeve inner surface and having an inner surface (50) arranged to face the spindle penetrant portion.

Abstract: The present invention provides an improvement for use in a machine tool having a spindle (51) mounted in a body opening (30) for axial and rotative movement relative to a body (31). The improvement includes a bearing assembly (25) that permits spindles (S1, S2, S3, . . . ) to be quickly exchanged while obviating the need to recenter a replacement spindle with respect to the opening after the original spindle has been initially center therein. The improved bearing assembly (25) broadly includes: a ferrous tubular sleeve (29) mounted in the body opening, the sleeve having an outer surface (40) arranged to face toward a portion (31) of the body that surrounds the opening and having an inner surface (36, 39) arranged to face toward a penetrant portion of the spindle; and a tubular bearing (46) arranged within the sleeve, the tubular bearing having an outer surface (51) arranged to face the sleeve inner surface and having an inner surface (50) arranged to face the spindle penetrant portion.