Patent US6422757B1 successfully refreshed from Google Patents.
US6422757B1
Expired / Lapsed
US
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Active piezoelectric spindle bearing preload adjustment mechanism
Assignee: Industrial Technology Research Institute
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Filing: 2000-12-15
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Granted: 2002-07-23
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Expires: 2020-12-15
Abstract
Abstract An active piezoelectric spindle bearing preload adjustment mechanism includes a preload adjustment assembly located between an inner ring and an outer ring of two bearings, and an internal generator mounted at a selected location in a spindle. The preload adjustment assembly includes a spacer ring set and a piezoelectric actuator located in the spacer ring set. The rotation speed of the spindle is changeable to enable the internal generator generating selected amount of power and voltage for controlling extension or contraction length of the piezoelectric actuator whereby to change slide distance between the inner and outer ring for controlling bearing preload value.
Inventors
- 👤 Tung-Chuan Wu
- 👤 Jih-Jong Hsu
- 👤 Kuan-Wen Chen
- 👤 Tsann-Huei Chang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:33
CPC Classifications
F; F16; F16C; F16C25/00; F16C25/06; F16C25/08; F16C19/00; F16C19/54; F16C19/546; F16C19/547; F16C19/548; F16C2202/00; F16C2202/30; F16C2202/36; F16C2322/00; F16C2322/39; Y; Y10; Y10T; Y10T409/00; Y10T409/30; Y10T409/309352
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
108 words
An active piezoelectric spindle bearing preload adjustment mechanism, comprising: a preload adjustment assembly located between an inner ring and an outer ring of two sets of bearing including a spacer ring set and a piezoelectric actuator located in the spacer ring set; and an internal generator disposed at a selected location in a spindle and driven by a rotary shaft for rotation; wherein rotation speed of the rotary shaft is changeable for the internal generator to generate selected amount of electric power and voltage for controlling extension length of the piezoelectric actuator whereby to change slide distance between the inner and outer ring for controlling bearing preload value.
Claim 2
Dependent Claim
108 words
An active piezoelectric spindle bearing preload adjustment mechanism, comprising: a preload adjustment assembly located between an inner ring and an outer ring of two sets of bearing including a spacer ring set and a piezoelectric actuator located in the spacer ring set; and an internal generator disposed at a selected location in a spindle and driven by a rotary shaft for rotation; wherein rotation speed of the rotary shaft is changeable for the internal generator to generate selected amount of electric power and voltage for controlling extension length of the piezoelectric actuator whereby to change slide distance between the inner and outer ring for controlling bearing preload value.
Claim 3
Dependent Claim
27 words
The active piezoelectric spindle bearing preload adjustment mechanism of claim 1 , wherein the spacer ring set includes a first spacer ring and a second spacer ring.
Claim 4
Dependent Claim
25 words
The active piezoelectric spindle bearing preload adjustment mechanism of claim 2 further having a gap located between the first spacer ring and second spacer ring.
Claim 5
Dependent Claim
30 words
The active piezoelectric spindle bearing preload adjustment mechanism of claim 2 , wherein the first spacer ring includes a first ring and a second ring which form a compartment therebetween.
Claim 6
Dependent Claim
28 words
The active piezoelectric spindle bearing preload adjustment mechanism of claim 1 , wherein the internal generator includes a coil and a magnet and is wired to a rectifier.
Claim 7
Dependent Claim
19 words
The active piezoelectric spindle bearing preload adjustment mechanism of claim 5 , wherein the rectifier is a semiconductor rectifier.
Claim 8
Dependent Claim
40 words
The active piezoelectric spindle bearing preload adjustment mechanism of claim 5 , wherein the magnet is mounted on the shaft and is rotated with the shaft, the coil is located in a stationary spindle front block corresponding to the magnet.
Claim 9
Dependent Claim
19 words
The active piezoelectric spindle bearing preload adjustment mechanism of claim 5 , wherein the magnet is a permanent magnet.
Claim 10
Dependent Claim
31 words
The active piezoelectric spindle bearing preload adjustment mechanism of claim 1 , wherein the spacer ring set is located between the bearings which are being disposed in a back-to-back assembly fashion.
Claim 11
Dependent Claim
35 words
The active piezoelectric spindle bearing preload adjustment mechanism of claim 9 , wherein the spacer ring set is compressed between the back-to-back assembly bearings for providing the spindle an initial bearing preload before spindle rotation.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2005-07-22 | 2006-01-21 | 2006-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-07-22 | 2010-01-21 | 2010-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-07-22 | 2014-01-21 | 2014-07-23 | $7700.00 | Window Closed / Lapsed |