US4294120A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Torsional vibration monitoring apparatus for rotating shaft system
Assignee: Individual
•
Filing: 1979-06-08
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Granted: 1981-10-13
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Expires: 1999-06-08
Abstract
Abstract An apparatus for monitoring torsional vibrations of a rotating shaft system such as for a turbine generator in which torsional vibrations at certain positions of the rotating shaft system are detected by detectors and the detected vibrations are converted into torsional vibration at an arbitrary position of the rotating shaft system by using an operation device having desired transfer characteristics, said arbitrary position is monitored on torsional vibration on the basis of the converted torsional vibration.
Inventors
- 👤 Ichiji Shima
- 👤 Tatsuo Yamamoto
- 👤 Shigeru Yoshibayashi
- 👤 Hiroshi Teshima
- 👤 Akio Hizume
- 👤 Tetsuo Iki
- 👤 Takashi Yamamoto
- 👤 Kyozo Kanamori
- 👤 Shigeho Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:51
CPC Classifications
G; G01; G01H; G01H1/00; G01H1/003
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
154 words
A torsional vibration monitoring apparatus for a rotating shaft system in which the torsional vibration of the rotating shaft system is monitored by estimating torsional vibration at arbitrary positions x j of the rotating shaft system from torsional vibration detected at a certain position x p of the rotating shaft system on the basis of the facts that a torsional vibration Y(x,t) produced in a rotating shaft system is an accumulation of modal vibrations Y i (x,t) and that each modal vibration is a product of a vibration mode type g i (x) and a vibration mode component h i (t), comprising a detector for detecting the torsional vibration at the certain position x p of the rotating shaft system and an operator having a transfer characteristic for converting the torsional vibration detected at the certain position x p into the torsional vibration at the arbitrary position x j of the rotating shaft system.
Claim 2
Dependent Claim
154 words
A torsional vibration monitoring apparatus for a rotating shaft system in which the torsional vibration of the rotating shaft system is monitored by estimating torsional vibration at arbitrary positions x j of the rotating shaft system from torsional vibration detected at a certain position x p of the rotating shaft system on the basis of the facts that a torsional vibration Y(x,t) produced in a rotating shaft system is an accumulation of modal vibrations Y i (x,t) and that each modal vibration is a product of a vibration mode type g i (x) and a vibration mode component h i (t), comprising a detector for detecting the torsional vibration at the certain position x p of the rotating shaft system and an operator having a transfer characteristic for converting the torsional vibration detected at the certain position x p into the torsional vibration at the arbitrary position x j of the rotating shaft system.
Claim 3
Dependent Claim
58 words
A torsional vibration monitoring apparatus as claimed in claim 1, wherein said operator has the transfer characteristics G.sub.j (S)=(Σg.sub.i (x.sub.j)·(m.sub.i S.sup.2 +c.sub.i S+k.sub.i))/(Σg.sub.i (x.sub.p)·(m.sub.i S.sup.2 +c.sub.i S+k.sub.i)) where m i is an i-th effective mass, c i is an i-th effective attenuation, k i is an i-th spring constant and g i is an i-th effective external coefficient.
Claim 4
Dependent Claim
81 words
A torsional vibration monitoring apparatus as claimed in claim 1, further comprising a fatigue operation circuit including extreme value detectors for detecting extreme values σ j .sup.(k) (k=1, 2, . . . ) of a stress at the arbitrary position x j which are outputs of said operator, a switching device for combining outputs of said extreme value detecters and a computer for computing and estimating a fatigue life expenditure at the arbitrary position x j of the rotating shaft system.
References Cited (Backward Citations)
US4051427A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-12 | 1985-04-13 | 1985-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-12 | 1989-04-13 | 1989-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-12 | 1993-04-13 | 1993-10-13 | $7700.00 | Window Closed / Lapsed |