PURPOSE: To improve the lubricity by forming a thrust bearing by forming a dynamic pressure generating groove on one between a thrust receiving plate and a supporting member and fitting the edge part of a motor shaft into a fluid sealed chamber.
CONSTITUTION: A thrust bearing part is formed from a thrust receiving plate 7 having a spiral groove 6 and a supporting member 8, and supported in rotatable ways by a radial bearing 11 installed at the edge part of a motor shaft. The motor shaft edge part is fitted into a fluid sealed chamber 9, and used as spiral groove bearing. Therefore, the generation of decomposition gas of the lubricating oil which is generated in case of the prior ball bearing can be suppressed, and the deterioration of the lubricating agent can be prevented.
HARADA HIDEOMI
OSADA NORIYUKI
KANAMORI TOSHIYA
