US6059524A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Penetration resistant fan casing for a turbine engine
Assignee: RTX Corp
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Filing: 1998-04-20
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Granted: 2000-05-09
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Expires: 2018-04-20
Abstract
Abstract The invention is a penetration resistant turbine engine fan casing (12) for containing separated fragments of a fan blade (16). The casing includes a penetration susceptible support case (14), a penetrable covering (32) circumscribing an impact zone (I) of the support case and an optional, but highly recommended collapsible support covering (34) circumscribing the case but axially offset from the impact zone. A containment covering (36) circumscribes both the penetrable covering (32) and the support covering (34). In a preferred embodiment, the coverings are aromatic polyamide fiber fabrics and the support covering is a collapsible cellular array. In operation, a detached fragment of a fan blade penetrates through the case (14) and the penetrable covering (32), and is plastically deformed by the penetrable covering to reduce the fragment's potential for damaging the containment covering (36). The containment covering intercepts the deformed fragment, confining it to a predetermined radial envelope bounded by the inner surface (58) of a nacelle (52). The impact forces arising from a separated blade fragment cause the containment fabric to collapse the cellular array (32) and momentarily detension the containment fabric to maximize its penetration resistance.
Inventors
- 👤 Mark W. Costa
- 👤 Andrew S. Foose
- 👤 Nathan D. Korn
- 👤 Jan B. Kowza
- 👤 Wendy P. Lopardi
- 👤 Douglas A. Welch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:31
CPC Classifications
F; F01; F01D; F01D25/00; F01D25/24; F01D21/00; F01D21/04; F01D21/045; F02; F02C; F02C7/00; F02C7/04; F05; F05D; F05D2240/00; F05D2240/10; F05D2240/14; Y; Y02; Y02T; Y02T50/00; Y02T50/60
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
39 words
A turbine engine fan casing for containing a separated blade fragment, comprising: a support case having an axially extending impact zone; a substantially structurally continuous penetrable covering circumscribing the impact zone; and a containment covering circumscribing the penetrable covering.
Claim 2
Dependent Claim
39 words
A turbine engine fan casing for containing a separated blade fragment, comprising: a support case having an axially extending impact zone; a substantially structurally continuous penetrable covering circumscribing the impact zone; and a containment covering circumscribing the penetrable covering.
Claim 3
Dependent Claim
63 words
The fan casing of claim 1 wherein the penetrable covering and the containment covering are fabric coverings, the containment fabric has a forward end situated axially forwardly of the penetrable fabric, and an aft end situated axially aftwardly of the penetrable fabric, and at least one of the ends is anchored to the support case by a joint effected by a bonding agent.
Claim 4
Dependent Claim
35 words
The fan casing of claim 1 comprising a support covering circumscribing the support case and axially offset from the impact zone, and wherein the containment covering circumscribes both the penetrable covering and the support covering.
Claim 5
Dependent Claim
32 words
The fan casing of claim 1 or 3 wherein the penetrable covering deforms the separated fragment and the containment covering resists penetration and confines the deformed fragment to a predetermined radial envelope.
Claim 6
Dependent Claim
26 words
The fan casing of claim 4 wherein the predetermined radial envelope is defined by a nacelle surface that circumscribes and is radially spaced from the casing.
Claim 7
Dependent Claim
34 words
The fan casing of claim 1 or 3 wherein the penetrable covering is a fabric having a first set of properties and the containment covering is a fabric having a second set of properties.
Claim 8
Dependent Claim
19 words
The fan casing of claim 6 wherein the penetrable covering and the containment covering are aromatic polyamide fiber fabrics.
Claim 9
Dependent Claim
54 words
The fan casing of claim 6 wherein the properties of the penetrable fabric include a weight per unit area and the properties of the containment fabric also include a weight per unit area, the weight per unit area of the containment fabric being less than the weight per unit area of the penetrable fabric.
Claim 10
Dependent Claim
83 words
The fan casing of claim 6 wherein the penetrable fabric has warp direction fibers and weft direction fibers, the properties of the penetrable fabric include a breaking strength in the warp direction and a breaking strength in the weft direction, the breaking strength in the weft direction being greater than the breaking strength in the warp direction, the penetrable fabric being oriented so that the lower strength warp direction fibers extend substantially circumferentially and the higher strength weft direction fibers extend substantially axially.
Claim 11
Dependent Claim
59 words
The fan casing of claim 1 wherein the penetrable covering is a fabric wrapped around the support case with substantially no tension and the containment covering is a fabric wrapped around the penetrable fabric with a predefined tension selected so that the containment fabric resists penetration by the blade fragment and confines the fragment to a predetermined radial envelope.
Claim 12
Dependent Claim
62 words
The fan casing of claim 3 wherein the penetrable covering is a fabric wrapped around the support case with substantially no tension and the containment covering is a fabric wrapped around the penetrable fabric and the support covering with a predefined tension so that the containment fabric resists penetration by the blade fragment and confines the fragment to a predetermined radial envelope.
Claim 13
Dependent Claim
29 words
The fan casing of claim 10 or 11 wherein the containment fabric has an axial length and the predefined tension is approximately ten pounds per inch of axial length.
Claim 14
Dependent Claim
14 words
The fan casing of claim 11 wherein the support covering is a collapsible covering.
Claim 15
Dependent Claim
14 words
The fan casing of claim 13 wherein the collapsible covering is a cellular array.
Claim 16
Dependent Claim
17 words
The fan casing of claim 13 wherein the collapsible covering conforms to SAE Aerospace Material Specification 3711B.
Claim 17
Dependent Claim
63 words
The fan casing of claim 3 wherein the penetrable covering and the containment covering are fabric coverings, the containment fabric has a forward end situated axially forwardly of the penetrable fabric and an aft end situated axially aftwardly of the support covering and at least one of the ends is anchored to the support case by a joint effected by a bonding agent.
Claim 18
Dependent Claim
37 words
The fan casing of claim 2 or 16 wherein the support case includes a circumferentially extending filler wedge nested in a corner of the support case and trapped radially between the support case and the containment fabric.
Claim 19
Dependent Claim
16 words
The fan casing of claim 2 or 16 wherein the bonding agent is an epoxy adhesive.
Claim 20
Dependent Claim
14 words
The fan casing of claim 2 or 16 wherein the joint is circumferentially continuous.
Claim 21
Dependent Claim
67 words
The fan casing of claim 2 or 16 wherein the separated blade fragment penetrates the impact zone at an impact site thereby opening a rupture in the support case, and a sector of the joint breaks so that a detached edge of the containment fabric is pulled a limited distance axially toward the impact site to at least partially detention the containment fabric without exposing the rupture.
Claim 22
Dependent Claim
168 words
A turbine engine fan casing for containing a separated blade fragment that strikes the fan casing, comprising: a support case having an axially extending impact zone; an aromatic polyamide penetrable fabric circumscribing the impact zone with substantially no tension; a collapsible cellular array circumscribing the support case and axially offset from the impact zone; an aromatic polyamide, penetration resistant containment fabric circumscribing the penetrable fabric and the cellular array with a predefined tension, the containment fabric having forward and aft ends situated axially beyond the penetrable fabric and the cellular array, the forward and aft ends each being anchored to the support case by respective adhesively bonded joints; and a circumferentially extending filler wedge nested in a corner of the support case and trapped radially between the support case and the containment fabric; wherein the penetrable covering deforms the separated blade fragment to reduce its potential for inflicting damage and the containment covering resists penetration by the deformed fragment thereby confining the fragment to a predetermined radial envelope.
Claim 23
Dependent Claim
168 words
A turbine engine fan casing for containing a separated blade fragment that strikes the fan casing, comprising: a support case having an axially extending impact zone; an aromatic polyamide penetrable fabric circumscribing the impact zone with substantially no tension; a collapsible cellular array circumscribing the support case and axially offset from the impact zone; an aromatic polyamide, penetration resistant containment fabric circumscribing the penetrable fabric and the cellular array with a predefined tension, the containment fabric having forward and aft ends situated axially beyond the penetrable fabric and the cellular array, the forward and aft ends each being anchored to the support case by respective adhesively bonded joints; and a circumferentially extending filler wedge nested in a corner of the support case and trapped radially between the support case and the containment fabric; wherein the penetrable covering deforms the separated blade fragment to reduce its potential for inflicting damage and the containment covering resists penetration by the deformed fragment thereby confining the fragment to a predetermined radial envelope.
Claim 24
Dependent Claim
49 words
The fan casing of claim 21 wherein a sector of at least one of the adhesively bonded joints breaks and the cellular array collapses in response to the blade fragment piercing the support case and striking the penetration resistant fabric thereby enhancing the penetration resistance of the containment fabric.
Claim 25
Independent Claim
53 words
A method of containing a separated fan blade fragment in a turbine engine, comprising: preconditioning the separated blade fragment to reduce its potential for inflicting damage; and intercepting the preconditioned fragment with a tensioned material capable of resisting penetration by the deformed fragment and of confining the fragment to a predetermined radial envelope.
Claim 26
Independent Claim
53 words
A method of containing a separated fan blade fragment in a turbine engine, comprising: preconditioning the separated blade fragment to reduce its potential for inflicting damage; and intercepting the preconditioned fragment with a tensioned material capable of resisting penetration by the deformed fragment and of confining the fragment to a predetermined radial envelope.
Claim 27
Dependent Claim
17 words
The method of claim 23 wherein the step of preconditioning the fragment comprises plastically deforming the fragment.
Claim 28
Dependent Claim
20 words
The method of claim 24 wherein the step of intercepting the fragment includes at least partially detensioning the tensioned material.
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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) | 2003-05-09 | 2003-11-08 | 2004-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-05-09 | 2007-11-08 | 2008-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-05-09 | 2011-11-08 | 2012-05-09 | $7700.00 | Window Closed / Lapsed |