Fluid bearing device and its manufacturing method

Abstract

To provide a fluid bearing device in which a bearing sleeve can be easily assembled to a housing and which has excellent moment rigidity. [MEANS FOR SOLVING THE PROBLEMS] This fluid bearing device (1) comprises radial bearing parts (R1, R2) and thrust bearing parts (T1, T2). Thrust bearing surfaces (C, D) are provided on the first and second step surfaces (2d, 2e) of the housing (2) respectively. The thrust bearing parts (T1, T2) are formed between the thrust bearing surfaces (C, D) and the end surfaces (6b, 7b) of seal members (6, 7) projecting to the outer diameter side of a shaft member (5).

Description

technical field [0001] The present invention relates to a fluid bearing device and a method of manufacturing the same. Background technique [0002] A fluid bearing device supports a shaft member on a rotating member using a lubricating film of fluid generated in a bearing gap. This fluid bearing device has the characteristics of high-speed rotation, high rotation accuracy, and low noise. In recent years, it has been used as a bearing device for electric motors that firstly mount information equipment on various electrical appliances, and more specifically, as a magnetic disk such as HDD. Devices, CD-ROM, CD-R / RW, DVD-ROM / RAM and other optical disc devices, MD, MO and other optical disk devices, such as spindle motors, laser printers (LBP) polygon scanner motors, projector color film motors, Bearing devices for electric motors such as fan motors are preferably used. [0003] For example, as a fluid bearing device equipped with a spindle motor for a disk drive, Figure 14 T...

AI Technical Summary

Problems solved by technology

[0010] However, as described in the above-mentioned Patent Documents 2 and 3, the case of fixing the bearing sleeve at two positions in the axial direction is more advantageous than the structure of Patent Document 1 in terms of improving the torque rigidity. However, on the other hand, it is necessary to Pay special attention to the assembly accuracy of the bearing sleeves with each other

That is, the reason is that when the bearing sleeve is fixed in a state where the position is deviated from the axial direction, for example, the arrangement space of the seal member and the cover member may not be ensured, and a predetermined thrust bearing clearance may not be formed on the end side of the bearing sleeve.

In addition, the reason is that when the two bearing sleeves are fixed in a state of being offset from each other in the radial direction, the concentricity between the radial bearing surfaces cannot be ensured, and problems such as deterioration of rotation accuracy and uneven wear of the bearing sleeves arise.

However, since there are dimensional tolerances in the housing and the bearing housing, it is not easy to position them with high precision.

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