Abstract: A fluid dynamic bearing including a shaft rotating within a sleeve and a thrust plate or the like supported at an end of the shaft rotating in a recess defined with the sleeve. The thrust plate faces a counterplate supported from the sleeve over the recess, and the sleeve and shaft are supported for rotation by fluid in the gap or gaps between the shaft and sleeve, thrust plate and sleeve, and thrust plate and counterplate. To prevent fluid from leaking out of the fluid dynamic bearing into the surrounding atmosphere by seeping between the counterplate and sleeve face it rests on, a seal recess is defined in the sleeve, a crush ring seal is placed in the recess. The counterplate is then pressed into the recess, crushing the crush seal ring and blocking any passage of the fluid from the gap region surrounding the thrust plate through the gap between counterplate and sleeve.

Abstract: A fluid dynamic bearing including a shaft rotating within a sleeve and a thrust plate or the like supported at an end of the shaft rotating in a recess defined with the sleeve. The thrust plate faces a counterplate supported from the sleeve over the recess, and the sleeve and shaft are supported for rotation by fluid in the gap or gaps between the shaft and sleeve, thrust plate and sleeve, and thrust plate and counterplate. To prevent fluid from leaking out of the fluid dynamic bearing into the surrounding atmosphere by seeping between the counterplate and sleeve face it rests on, a seal recess is defined in the sleeve, a crush ring seal is placed in the recess. The counterplate is then pressed into the recess, crushing the crush seal ring and blocking any passage of the fluid from the gap region surrounding the thrust plate through the gap between counterplate and sleeve.

Abstract: A fluid dynamic bearing including a shaft rotating within a sleeve and a thrust plate or the like supported at an end of the shaft rotating in a recess defined with the sleeve. The thrust plate faces a counterplate supported from the sleeve over the recess, and the sleeve and shaft are supported for rotation by fluid in the gap or gaps between the shaft and sleeve, thrust plate and sleeve, and thrust plate and counterplate. To prevent fluid from leaking out of the fluid dynamic bearing into the surrounding atmosphere by seeping between the counterplate and sleeve face it rests on, a seal recess is defined in the sleeve, a crush ring seal is placed in the recess. The counterplate is then pressed into the recess, crushing the crush seal ring and blocking any passage of the fluid from the gap region surrounding the thrust plate through the gap between counterplate and sleeve.

Abstract: An apparatus and method are provided for sealing and electrically coupling an outer surface 170 of a shaft 175 to an inner surface 165 of a hub 160 disposed about the shaft. The invention is particularly useful for spindle motors 155 used in disc drives 100. In one embodiment, a seal 185 having a pair of annular pole pieces 270a, 270b, coupled to opposite poles of a magnet 265 is positioned between the shaft 175 and the hub 160. A nonmagnetic, electrically conductive ring 275 electrically couples the pole pieces 270a, 270b to one another and to the hub 160. In one version, the electrically conductive ring 275 includes an annular disk 300 with tabs 305 projecting from the exterior radius. The disk 300 abuts one pole piece 270b and the tabs 305 are folded over to electrically couple to the other 270a.