US4779165A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Disk storage drive
Assignee: Papst Licensing GmbH and Co KG
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Filing: 1987-03-31
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Granted: 1988-10-18
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Expires: 2007-03-31
Abstract
Abstract A disk storage drive is provided with a brushless drive motor having a stator with a winding. An external rotor coaxially surrounds the stator and is spaced therefrom by a substantially cylindrical air gap. The rotor includes a permanent magnet and a soft magnetic yoke. A hub is provided that is concentric to the yoke and is connected to the rotor for rotation therewith. The hub has a disk mounting portion on its outer peripheral surface that can be passed through the central opening of a standardized storage disk for mounting the storage disks for rotation therewith. At least half of the axial longitudinal dimension of the stator winding and the rotor magnet interacting therewith is housed within the disk mounting portion of the hub. The hub is made from a non-ferromagnetic material that is suitable for storage drive clean chamber use after dimensional finishing of the hub.
Inventors
- 👤 Dieter Elsaesser
- 👤 Johann von der Heide
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:35
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/50; G11B23/505; G11B17/00; G11B17/02; G11B17/038; G11B19/00; G11B19/20; G11B19/2009; G11B25/00; G11B25/04; G11B25/043; H; H02; H02K; H02K11/00; H02K11/01; H02K11/012; H02K11/30; H02K11/33; H02K11/40; H02K21/00; H02K21/12; H02K21/22; H02K29/00; H02K29/06; H02K29/08; H02K5/00; H02K5/04; H02K5/10; H02K5/12; H02K5/124; H02K5/16; H02K5/173; H02K5/1735; H02K5/1737; H02K5/22; H02K5/225; H02K7/00; H02K7/08; H02K7/085; H02K7/086; H02K7/14; H02P; H02P6/00; H02P6/08; H02P6/085; H02K2211/00; H02K2211/03; H02K3/00; H02K3/04; H02K3/28; H02K5/167; H02P2209/00; H02P2209/07
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
292 words
A disk storage drive comprising: a clean chamber for housing a storage disk; a brushless drive motor having a stator and a winding on the stator, the stator having an axial longitudinal dimension and the winding having a pair of opposed end surfaces; an external rotor having a rotation axis and coaxially surrounding the stator, an inner wall of said rotor being spaced from said stator by a substantially cyclindrical air gap, said rotor having a permanent magnet with an axial longitudinal dimension and a soft magnetic yoke with an axially extending wall portion and a radially extending wall portion, said permanent magnet forming the inner wall of aaid rotor adjacent the air gap; a hub held fast on the rotor for rotation therewith and being coaxial to the yoke, said hub having a machinable outer surface and being made of a non-ferromagnetic, non-corrodible material suitable for use in a clean chamber following machining of the outer surface; an outer peripheral cylindrical surface on said hub dimensioned to pass through a standardized central opening of a storage disk for receiving and mounting the storage disk for rotation therewith in said clean chamber, said outer peripheral cylindrical surface radially enclosing said soft magnetic yoke of said rotor and said stator for a substantial part of the axial extensions thereof, and at least half of the axial longitudinal dimension of th stator winding and of the rotor magnet interacting magnetically therewith being housed within said outer peripheral cylindrical surface of the storage disk mounting portion of the hub, and said yoke radial wall portion extending radially inwardly from one axial end of the yoke axial wall portion by a distance sufficient to extend over the adjacent one of said pair of winding end surfaces.
Claim 2
Dependent Claim
292 words
A disk storage drive comprising: a clean chamber for housing a storage disk; a brushless drive motor having a stator and a winding on the stator, the stator having an axial longitudinal dimension and the winding having a pair of opposed end surfaces; an external rotor having a rotation axis and coaxially surrounding the stator, an inner wall of said rotor being spaced from said stator by a substantially cyclindrical air gap, said rotor having a permanent magnet with an axial longitudinal dimension and a soft magnetic yoke with an axially extending wall portion and a radially extending wall portion, said permanent magnet forming the inner wall of aaid rotor adjacent the air gap; a hub held fast on the rotor for rotation therewith and being coaxial to the yoke, said hub having a machinable outer surface and being made of a non-ferromagnetic, non-corrodible material suitable for use in a clean chamber following machining of the outer surface; an outer peripheral cylindrical surface on said hub dimensioned to pass through a standardized central opening of a storage disk for receiving and mounting the storage disk for rotation therewith in said clean chamber, said outer peripheral cylindrical surface radially enclosing said soft magnetic yoke of said rotor and said stator for a substantial part of the axial extensions thereof, and at least half of the axial longitudinal dimension of th stator winding and of the rotor magnet interacting magnetically therewith being housed within said outer peripheral cylindrical surface of the storage disk mounting portion of the hub, and said yoke radial wall portion extending radially inwardly from one axial end of the yoke axial wall portion by a distance sufficient to extend over the adjacent one of said pair of winding end surfaces.
Claim 3
Dependent Claim
40 words
A disk storage drive as claimed in claim 1, wherein at lest two-thirds of said axial longitudinal dimension of the stator winding and of the rotor magnet interacting magnetically therewith is housed within the disk mounting portion of the hub.
Claim 4
Dependent Claim
31 words
A disk storage drive as claimed in claim 2, wherein the stator winding and the rotor magnet interacting therewith are substantially completely housed within the disk mounting portion of the hub.
Claim 5
Dependent Claim
32 words
A disk storage drive as claimed in claim 1, wherein the wall of the disk mounting portion is no thicker than the wall of the part of the magnetic yoke coaxial therewith.
Claim 6
Dependent Claim
21 words
A disk storage drive as claimed in claim 4, wherein the disk support mounting wall is thinner than said yoke wall.
Claim 7
Dependent Claim
17 words
A disk storage drive as claimed in claim 1, wherein the hub is made from light metal.
Claim 8
Dependent Claim
39 words
A disk storage drive as claimed in claim 1, wherein the external circumferential surface of the disk mounting portion of the hub, after assembly of hub and drive motor, is finished with respect to centricity with the rotation axis.
Claim 9
Dependent Claim
18 words
A disk storage drive as claimed in claim 7, wherein said surface is ground or turned to finish.
Claim 10
Dependent Claim
16 words
A disk storage drive as claimed in claim 1, wherein the hub is extruded or cast.
Claim 11
Dependent Claim
19 words
A disk storage drive as claimed in claim 1, wherein the hub is pressed hot on the magnetic yoke.
Claim 12
Dependent Claim
15 words
A disk storage drive as claimed in claim 1, wherein the magnetic yoke is annular.
Claim 13
Dependent Claim
40 words
A disk storage drive as claimed in claim 11, wherein a magnetic shield ring is placed in the hub and extends from the inside wall of the hub radially inwardly and substantially from one axial end of the annular yoke.
Claim 14
Dependent Claim
40 words
A disk storage drive as claimed in claim 1, wherein the rotor and the hub are fixed to a shaft rotatably supported axially in a bearing system that is at least partly housed within the stator of the drive motor.
Claim 15
Dependent Claim
26 words
A disk storage drive as claimed in claim 13, wherein a bearing bush receiving the shaft is formed integrally in the hub or the magnetic yoke.
Claim 16
Dependent Claim
26 words
A disk storage drive as claimed in claim 14, wherein the bearing system is sealed by means of at least one magnetic fluid or ferro-fluidic seal.
Claim 17
Dependent Claim
27 words
A disk storage drive as claimed in claim 15, wherein the magnetic fluid or ferro-fluidic seal is positioned adjacent to but axially spaced from the bearing bush.
Claim 18
Dependent Claim
28 words
A disk storasge drive as claimed in claim 1, wherein the rotor and the hub are rotatably mounted by means of a bearing system on a fixed shaft.
Claim 19
Dependent Claim
29 words
A disk storage drive as claimed in claim 17, wherein leads are provided for the stator winding that pass through the fixed shaft to the outside of the drive.
Claim 20
Dependent Claim
34 words
A disk storage drive as claimed in claim 1, wherein a control magnet is connected to the unit that includes the rotor and hub, and interacts with a stationary, magnetic field-sensitive rotation position sensor.
Claim 21
Dependent Claim
35 words
A disk storage drive as claimed in claim 19, wherein the control magnet is positioned on that side of the unit that includes the rotor and hub and that is open in the axial direction.
Claim 22
Dependent Claim
20 words
A disk storage drive as claimed in claim 19, wherein the control magnet is axially aligned with the rotor magnet.
Claim 23
Dependent Claim
43 words
A disk storage drive as claimed in claim 19, wherein the rotation position sensor is mounted on a printed circuit board that axially faces the side of the unit that includes the rotor and hub and that is open in the axial direction.
Claim 24
Dependent Claim
24 words
A disk storage drive as claimed in claim 1, wherein the ratio of inner and outer diameters of the stator is at least 0.35.
Claim 25
Dependent Claim
16 words
A disk storage drive as claimed in claim 23, wherein said ratio is 0.4 to 0.7.
Claim 26
Dependent Claim
25 words
A disk storage drive as claimed in claim 1, wherein the ratio of axial length to external diameter of the stator does not exceed 1.
Claim 27
Dependent Claim
272 words
A disk storage drive comprising: a clean chamber for housing a storage disk; a brushless drive motor having a stator and a winding on the stator, the stator having an axial longitudinal dimension; an external rotor having a rotation axis and coaxially surrounding the stator, an inner wall of said rotor being spaced from said stator by a substantially cylindrical air gap, said rotor having a permanent magnet with an axial longitudinal dimension and a soft magnetic annular yoke with an axially extending wall portion, said permanent magnet forming the inner wall of said rotor adjacent the air gap; a hub held fast on the rotor for rotation therewith and being coaxial to the yoke, said hub having a machinable outer surface and being made of a non-ferromagnetic, non-corrodible material suitable for use in a clean chamber following machining of the outer surface; an outer peripheral cylindrical surface on said hub dimensioned to pass through a standardied central opening of a storage disk for receiving and mounting the storage disk for rotation therewith in said clean chamber, said outer peripheral cylindrical surface radially enclosing said soft magnetic yoke of said rotor and said stator for a substantial part of the axial extensions thereof, and at least half of the axial longitudinal dimension of the stator winding and of the rotor magnet interacting magnetically there with being housed within said outer peripheral cylindrical surface of the storage disk mounting portion of the hub; and a magnetic shield ring located in the hub and extending from the inside wall of the hub radially inwardly and substantially from one axial end of the annular yoke.
Claim 28
Dependent Claim
272 words
A disk storage drive comprising: a clean chamber for housing a storage disk; a brushless drive motor having a stator and a winding on the stator, the stator having an axial longitudinal dimension; an external rotor having a rotation axis and coaxially surrounding the stator, an inner wall of said rotor being spaced from said stator by a substantially cylindrical air gap, said rotor having a permanent magnet with an axial longitudinal dimension and a soft magnetic annular yoke with an axially extending wall portion, said permanent magnet forming the inner wall of said rotor adjacent the air gap; a hub held fast on the rotor for rotation therewith and being coaxial to the yoke, said hub having a machinable outer surface and being made of a non-ferromagnetic, non-corrodible material suitable for use in a clean chamber following machining of the outer surface; an outer peripheral cylindrical surface on said hub dimensioned to pass through a standardied central opening of a storage disk for receiving and mounting the storage disk for rotation therewith in said clean chamber, said outer peripheral cylindrical surface radially enclosing said soft magnetic yoke of said rotor and said stator for a substantial part of the axial extensions thereof, and at least half of the axial longitudinal dimension of the stator winding and of the rotor magnet interacting magnetically there with being housed within said outer peripheral cylindrical surface of the storage disk mounting portion of the hub; and a magnetic shield ring located in the hub and extending from the inside wall of the hub radially inwardly and substantially from one axial end of the annular yoke.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-10-18 | 1992-04-18 | 1992-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-18 | 1996-04-18 | 1996-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-18 | 2000-04-18 | 2000-10-18 | $7700.00 | Window Closed / Lapsed |