Back to results
US 5,880,545 AGranted
Spindle motor with bearing system having fluid sealing and leakage prevention
AssigneeNidec Corporation
InventorsYoshihiro Takemura, Osamu Wada, Kazuto Miyajima, Norikazu Oguchi, Shohei Fukunaga
Life of this patent
Estimating the term…
Abstract
The invention is a spindle motor including a rotor hub bearing a rotational load, lubricant-containing bearing systems rotatably supported by the rotor hub, and stator windings wound on a stationary member, so as to oppose the rotor magnet. At least a portion of the rotor hub is in a clean environment, with the motor substantially sealed by a sealing unit. The spindle motor has a leakage prevention unit which prevents the lubricant trying to leak out the bearing systems and out the motor, when centrifugal forces produced by a rotor hub rotating at a high speed are exerted on the lubricant.
Claims38
A spindle motor comprising:
- a shaft;
- a cylindrical rotor hub rotatable relative to said shaft;
- a pair of ball bearings filled with a lubricating fluid and interposed between said shaft and said rotor hub for supporting said rotor hub, said rotor hub being provided with at least one annular groove formed on its inner surface and opening toward the interior of said motor for trapping and retaining said lubricating fluid which oozes from said ball bearings and spreads along the inner surface of said rotor hub, thereby preventing said lubricating fluid from leaking to the exterior of said motor;
- a ring-shaped rotor magnet fixedly secured to said rotor hub;
- a stator opposing said rotor magnet;
- and
- a sealing means disposed axially outwardly of said ball bearings.
4 more elements
A spindle motor comprising:
- a shaft;
- a cylindrical rotor hub rotatable relative to said shaft;
- a pair of ball bearings filled with a lubricating fluid and interposed between said shaft and said rotor hub;
- a ring-shaped rotor magnet fixedly secured to said rotor hub;
- a stator opposing said rotor magnet;
- an annular bushing member interposed between said rotor hub and one of said ball bearings, said rotor hub and said annular bushing member being provided with at least one annular groove on respective inner surfaces of said rotor hub and said annular bushing member for trapping and retaining said lubricating fluid which oozes from said ball bearings and spreads along the inner surface of said rotor hub, thereby preventing said lubricating fluid from leaking to the exterior of said motor;
- a sealing means disposed axially outwardly of said ball bearings;
- and
- a ring-shaped member disposed on the upper surface of said annular bushing member so as to be in contact with the inner surface of said rotor hub.
6 more elements
A spindle motor comprising:
- a shaft;
- a cylindrical rotor hub rotatable relative to said shaft;
- a pair of ball bearings filled with a lubricating fluid and interposed between said shaft and said rotor hub, said rotor hub being provided with at least one annular groove on the inner surface of said rotor hub for trapping and retaining said lubricating fluid which oozes from said ball bearings and spreads along the inner surface of said rotor hub;
- thereby preventing said lubricating fluid from leaking to the exterior of said motor;
- a ring-shaped rotor magnet fixedly secured to said rotor hub;
- a stator opposing said rotor magnet;
- an annular bushing member interposed between said rotor hub and one of said ball bearings;
- a sealing means disposed axially outwardly of said ball bearings;
- and
- a ring-shaped member disposed on the upper surface of said annular bushing member so as to be in contact with the inner surface of said rotor hub.
7 more elements
A spindle motor comprising:
- a shaft;
- a cylindrical rotor hub rotatable relative to said shaft;
- a pair of ball bearings filled with a lubricating fluid and interposed between said shaft and said rotor hub;
- a ring-shaped rotor magnet fixedly secured to said rotor hub;
- a stator opposing said rotor magnet;
- an annular bushing member interposed between said rotor hub and one of said ball bearings, said bushing being provided with at least one annular groove on the inner surface of said bushing for trapping and retaining said lubricating fluid which oozes from said ball bearings and spreads along the inner surface of said rotor hub, thereby preventing said lubricating fluid from leaking out to the exterior of said motor;
- a sealing means disposed axially outwardly of said ball bearings;
- and
- a ring-shaped member disposed on the upper surface of said annular bushing member so as to be in contact with the inner surface of said rotor hub.
6 more elements
Dependencies are inferred from the claim text.