Patent US3881844A successfully refreshed from Google Patents.
US3881844A
Expired / Lapsed
US
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Blade platform vibration dampers
Assignee: General Electric Co
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Filing: 1974-05-28
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Granted: 1975-05-06
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Expires: 1994-05-28
Abstract
Abstract A turbomachinery assembly equipped with circumferentially disposed blades, having integral platforms and dovetails, is provided with a vibration damping means disposed circumferentially about the perimeter of a dovetail engaging the disc between the disc and the blade platforms. The vibration damper, in one embodiment, comprises a spiraled encasing means wound around a flexible core element. As the vibration damper is centrifugally forced into contact with the blade platform, blade platform vibratory energy is transmitted to the damping means and is dissipated as heat through relative frictional movement between adjacent portions of the encasing means and between the encasing means and the flexible core.
Inventors
- 👤 John D Hennessey
- 👤 Richard Beal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:53
CPC Classifications
F; F01; F01D; F01D5/00; F01D5/12; F01D5/22; F01D5/24; F01D5/30; F01D5/3023; F01D5/303; F01D5/3038; F05; F05D; F05D2260/00; F05D2260/96; Y; Y02; Y02T; Y02T50/00; Y02T50/60; Y10; Y10S; Y10S416/00; Y10S416/50
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
130 words
In a turbomachinery assembly including a fluid flow path, generally cylindrical support means, a plurality of radially extending blades attached to said support means, each of said blades comprising an airfoil, mounting means for attaching said blade to said support means, and a platform disposed in a spaced relationship with said support means and positioned between the airfoil and the mounting means for partially defining the flow path, vibration damping means comprising: encasing means disposed between said support means and said blade platform, being in frictional contact with and capable of exerting radial pressure on said blade platforms during operation in the fluid flow path, for damping blade platform movement; and a flexible core element cooperating with and movable with respect to said encasing means, and in frictional contact therewith.
Claim 2
Dependent Claim
130 words
In a turbomachinery assembly including a fluid flow path, generally cylindrical support means, a plurality of radially extending blades attached to said support means, each of said blades comprising an airfoil, mounting means for attaching said blade to said support means, and a platform disposed in a spaced relationship with said support means and positioned between the airfoil and the mounting means for partially defining the flow path, vibration damping means comprising: encasing means disposed between said support means and said blade platform, being in frictional contact with and capable of exerting radial pressure on said blade platforms during operation in the fluid flow path, for damping blade platform movement; and a flexible core element cooperating with and movable with respect to said encasing means, and in frictional contact therewith.
Claim 3
Dependent Claim
37 words
The vibration damping means of claim 1 wherein said encasing means comprises a flexible coil disposed in a spiral around said core element, predetermined of said turns of said spiral being in frictional contact with adjacent turns.
Claim 4
Dependent Claim
50 words
The vibration damping means of claim 2 wherein said core element is segmented, each segment disposed generally about a portion of the circumference of said support means and wherein said segments include restraining means to preclude substantial circumferential movement of said core element segments with respect to said support means.
Claim 5
Dependent Claim
42 words
The vibration damping means of claim 3 wherein said restraining means comprises a slot in said support means and wherein a predetermined portion of each segment is disposed at an angle to the remainder of the segment and keyed into said slot.
Claim 6
Dependent Claim
43 words
The vibration damping means of claim 1 wherein the encasing means comprises a plurality of members generally encircling said core element, said members movable relative to one another and to said core, and predetermined of said members in frictional contact with one another.
Claim 7
Dependent Claim
32 words
The vibration damping means of claim 5 wherein the plurality of members generally encircling the core are disposed at some angle other than 90* to the longitudinal axis of the core element.
Claim 8
Dependent Claim
17 words
The vibration damping means of claim 6 wherein the members generally encircling the core are discrete annuli.
Claim 9
Dependent Claim
50 words
The vibration damping means of claim 5 wherein said core element is segmented, each segment disposed generally about a portion of the circumference of said support means and wherein said segments include restraining means to preclude substantial circumferential movement of said core element segments with respect to said support means.
Claim 10
Dependent Claim
42 words
The vibration damping means of claim 8 wherein said restraining means comprises a slot in said support means and wherein a predetermined portion of each segment is disposed at an angle to the remainder of said segment and keyed into said slot.
Claim 11
Dependent Claim
38 words
The vibration damping means of claim 1 wherein said vibration damping means cooperates with said platform and said support structure to create a labyrinth flow path for inhibiting fluid flow between said support means and said blade platform.
Claim 12
Dependent Claim
33 words
The tUrbomachinery assembly of claim 10 further characterized in that said support means comprises a rotatable disc, and wherein said radial pressure is a result of centrifugal forces on said vibration damping means.
Claim 13
Dependent Claim
26 words
The vibration damping means of claim 11 wherein said disc includes a circumferential recess and wherein said vibration damping means is partially disposed within said recess.
Claim 14
Dependent Claim
26 words
The vibration damping means of claim 12 wherein said vibration damping means comprises a severed ring disposed circumferentially between said rotatable disc and said blade platform.
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) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |