| 摘要 |
A down-hole motor and bearing arrangement 22 includes a pair of longitudinally spaced apart bearings 26, 28 that each have multiple rows of ball bearings 36 positioned between a unitary inner race 34 and a two piece outer race 56. The inner race 34 includes a plurality of longitudinally spaced circumferential grooves 71-73 formed therein, while the outer race 56 includes a plurality of corresponding longitudinally spaced circumferential grooves 77-79 formed on an inner surface thereof. A series of openings 65-67 extend through the outer race 56 and intersect with the circumferential grooves 77-79. The openings 65-67 have a diameter slightly larger than the diameter of the ball bearings 36 but less than the longitudinal width of the grooves 77-79. Further, the openings 65-67 are positioned adjacent one longitudinal end of the circumferential grooves 77-79 so that the ball bearings 36 may be loaded therethrough when the inner race 34 is longitudinally positioned to align the circumferential grooves 71-73 with the openings 65-67. However, when the inner race 34 is longitudinally shifted, the ball bearings 36 are captured between the raised portions defining the grooves 71-73; 77-79, thereby preventing the ball bearings 36 from passing through the openings 65-67. <IMAGE> |
