US5217766A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilized complex composite preforms
Assignee: GKN Westland Aerospace Inc
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Filing: 1992-06-11
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Granted: 1993-06-08
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Expires: 2012-06-11
Abstract
Abstract A method for forming stabilized preforms for complex composite articles is disclosed using a solid meltable uncatalyzed thermosetting resin as the stabilizing agent. The resin is applied to each layer of the preform and heated to melt the resin and bond the layers together. After cooling, the resin resolidifies but does not set and thereby holds the layers in the desired preform shape. The layers can be first formed into a flat sheet as a raw material from which shaped preforms can be made by cutting the sheet into sections which are placed over a mandrel and reheating to thereby remelt the solid resin to allow the preform to conform to the shape of the mandrel. Utilizing this process allows complex composite parts to be easily preformed and assembled prior to placement in a mold for resin injection molding, without inhibiting part strength as the resin is compatible with the injection resin and is cocatalyzed by the catalyst contained in the injection resin.
Inventors
- 👤 Nicholas P. Flonc
- 👤 Michael W. Brace
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:50
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/04; B29C70/28; B29C70/54; B29C70/543; B29B; B29B11/00; B29B11/14; B29B11/16; B29B15/00; B29B15/08; B29B15/10; B29B15/105; Y; Y10; Y10S; Y10S428/00; Y10S428/902; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1043; Y10T156/1044; Y10T156/1048; Y10T428/00; Y10T428/13; Y10T428/131; Y10T428/1314; Y10T428/1317; Y10T428/1321; Y10T428/1352; Y10T428/1362; Y10T428/30; Y10T428/31504; Y10T428/31511; Y10T428/31515; Y10T428/31518; Y10T428/31551; Y10T428/31598; Y10T428/31601; Y10T428/31721; Y10T442/00; Y10T442/10; Y10T442/102; Y10T442/153; Y10T442/30; Y10T442/3472; Y10T442/3528; Y10T442/3569; Y10T442/3585; Y10T442/60; Y10T442/659; Y10T442/67; Y10T442/671
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
61 words
A stabilized composite preform comprising: a plurality of oriented fiber layers, the layers being stacked and having a normal room temperature-solid uncatalyzed thermosetting resin between each layer, the layers formed over a shaped mold surface, the solid uncatalyzed thermosetting resin being meltable for shaping the layers and being resolidifiable to rigidify the layers to form a shaped and stabilized composite preform.
Claim 2
Dependent Claim
61 words
A stabilized composite preform comprising: a plurality of oriented fiber layers, the layers being stacked and having a normal room temperature-solid uncatalyzed thermosetting resin between each layer, the layers formed over a shaped mold surface, the solid uncatalyzed thermosetting resin being meltable for shaping the layers and being resolidifiable to rigidify the layers to form a shaped and stabilized composite preform.
Claim 3
Dependent Claim
58 words
A finished, cured product produced by infiltrating a thermosetting resin containing a catalyst between the layers of the composite preform of claim 1 at a temperature sufficient to melt the meltable thermosetting resin initially contained in the preform and enable that melted resin to mix with said catalyst, thereby enabling catalyst-promoted cure of both thermosetting resins referred to.
Claim 4
Dependent Claim
25 words
The preform of claim 1 wherein the oriented fiber layers are composed of fibers from the group consisting of graphite, aramid, glass or carbon fibers.
Claim 5
Dependent Claim
22 words
The preform of claim 1 wherein the solid uncatalyzed thermosetting rein has a melting temperature of about 100° F. to 350° F.
Claim 6
Dependent Claim
21 words
The preform of claim 1 wherein the solid uncatalyzed thermosetting resin is present at between 1-15 percent by weight per layer.
Claim 7
Dependent Claim
65 words
A shaped preform produced by subjecting the preform of claim 1 to a process comprising cutting to a desired size, shaping the cut composite on a mandrel under heating conditions sufficient to melt the room temperature-solid resin and enable the composite to conform to the shape of the mandrel and cooling the shaped composite to enable the shaped preform to rigidify in the shaped state.
Claim 8
Dependent Claim
15 words
The preform of claim 1 wherein the solid uncatalyzed thermosetting resin is an epoxy resin.
Claim 9
Dependent Claim
82 words
A stabilized complex composite preform produced by the steps of: (a) providing a plurality of oriented fiber layers, (b) stacking the layers, (c) applying a meltable, normal room temperature-solid uncatalyzed thermosetting resin between each layer, (d) placing the stacked layers over a mold surface having a desired preform shape, (e) forming the layers over the mold surface, (f) heating the layers to melt the resin and lightly fuse the layers together, and, (g) cooling to rigidity the layers to form a preform.
Claim 10
Dependent Claim
82 words
A stabilized complex composite preform produced by the steps of: (a) providing a plurality of oriented fiber layers, (b) stacking the layers, (c) applying a meltable, normal room temperature-solid uncatalyzed thermosetting resin between each layer, (d) placing the stacked layers over a mold surface having a desired preform shape, (e) forming the layers over the mold surface, (f) heating the layers to melt the resin and lightly fuse the layers together, and, (g) cooling to rigidity the layers to form a preform.
Claim 11
Dependent Claim
66 words
A finished, cured product having a desired shape produced by impregnating the preform of claim 8 while in a desired configuration with a composition comprising a thermosetting resin and a catalyst at a temperature sufficient to melt the meltable thermosetting resin initially contained in the preform and enable that melted resin to mix with said catalyst, thereby enabling catalyst-promoted cure of both thermosetting resins referred to.
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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) | 1996-06-07 | 1996-12-07 | 1997-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-07 | 2000-12-07 | 2001-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-07 | 2004-12-07 | 2005-06-08 | $7700.00 | Window Closed / Lapsed |