US4930731A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dome and window for missiles and launch tubes with high ultraviolet transmittance
Assignee: Coors Porcelain Co
•
Filing: 1987-05-06
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Granted: 1990-06-05
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Expires: 2007-05-06
Abstract
Abstract A dome and window for missiles and launch tubes is provided having high ultraviolet transmittance and high strength properties. The domes and windows have, in their uncoated state, and with a thickness of about 1.88 mm, a transmittance greater than about 80%, preferably greater than about 82%, and more preferably greater than about 85%, at a wavelength of 0.4 microns to 0.5 microns. The domes and windows preferably have a transmittance per 1.88 mm thickness at all wavelengths in the wavelength range between 3.0 microns and 4.0 microns of at least about 81%. The domes and windows have a flexural strength of at least about 20,000 psi and a knoop hardness of at least about 1350 kg mm -2 . The domes and windows are formed of a transparent, sintered polycrystalline magnesia-alumina spinel. The polycrystalline sintered spinel is formed in a two-step process comprising forming a closed porosity body such as by hot-pressing or pressureless sintering followed by a hot isostatic pressure treatment step to reduce residual porosity to less than about 0.001 percent.
Inventors
- 👤 Donald W. Roy
- 👤 James L. Hastert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:59
CPC Classifications
F; F42; F42B; F42B10/00; F42B10/32; F42B10/38; F42B10/42; F42B10/46; C; C04; C04B; C04B35/00; C04B35/01; C04B35/44; C04B35/443; C04B35/622; C04B35/64; C04B35/645; C04B35/6455; F42B15/00; F42B15/34; H; H01; H01Q; H01Q1/00; H01Q1/42; C04B2235/00; C04B2235/02; C04B2235/30; C04B2235/32; C04B2235/3201; C04B2235/3203; C04B2235/3205; C04B2235/3206; C04B2235/3217; C04B2235/34; C04B2235/3418; C04B2235/44; C04B2235/444; C04B2235/445; C04B2235/50; C04B2235/54; C04B2235/5409; C04B2235/5418; C04B2235/5445; C04B2235/65; C04B2235/656; C04B2235/6565; C04B2235/6567; C04B2235/66; C04B2235/661; C04B2235/668; C04B2235/70; C04B2235/72; C04B2235/721; C04B2235/726; C04B2235/74; C04B2235/78; C04B2235/79; C04B2235/94; C04B2235/96; C04B2235/9646; C04B2235/9653
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
75 words
A dome for a missile guidance system comprising: a transparent, sintered polycrystalline body comprising magnesia-alumina spinel having a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 0.4 microns and 0.5 microns of at least about 82%, having a flexural strength of at least about 20,000 psi and having a knoop hardness of at least about 1350 kg mm -2; said body being formed in the shape of a convex shell.
Claim 2
Dependent Claim
75 words
A dome for a missile guidance system comprising: a transparent, sintered polycrystalline body comprising magnesia-alumina spinel having a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 0.4 microns and 0.5 microns of at least about 82%, having a flexural strength of at least about 20,000 psi and having a knoop hardness of at least about 1350 kg mm -2; said body being formed in the shape of a convex shell.
Claim 3
Dependent Claim
22 words
A dome, as claimed in claim 1, wherein: said body is formed in the shape of a sector of a spherical shell.
Claim 4
Dependent Claim
35 words
A dome, as claimed in claim 1, wherein: said body has a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 0.5 microns and 1.0 microns of at least about 85%.
Claim 5
Dependent Claim
53 words
A dome, as claimed in claim 1, wherein: said body has a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 3 microns and 4 microns of at least about 81% and all wavelengths in the wavelength region between 4 microns and 5 microns of at least about 76%.
Claim 6
Dependent Claim
76 words
A missile launch tube window comprising: a transparent, sintered polycrystalline body comprising magnesia-alumina spinel having a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 0.4 microns and 0.5 microns of at least about 82%, having a flexural strength of at least about 20,000 psi and having a knoop hardness of at least about 1350 kg mm -2; said launch tube window being formed in the shape of a substantially flat disk.
Claim 7
Dependent Claim
76 words
A missile launch tube window comprising: a transparent, sintered polycrystalline body comprising magnesia-alumina spinel having a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 0.4 microns and 0.5 microns of at least about 82%, having a flexural strength of at least about 20,000 psi and having a knoop hardness of at least about 1350 kg mm -2; said launch tube window being formed in the shape of a substantially flat disk.
Claim 8
Dependent Claim
37 words
A launch tube window, as claimed in claim 5, wherein: said body has a transmittance per 1.88 mm thickness at all wavelengths in the wavelength range between 0.5 microns and 1.0 microns of at least about 85%.
Claim 9
Dependent Claim
56 words
A launch tube window, as claimed in claim 5, wherein: said body has a transmittance per 1.88 mm thickness at all wavelengths in the wavelength range between 3.0 microns and 4.0 microns of at least about 81%, and at all wavelengths in the wavelength region between 4 microns and 5 microns of at least about 76%.
Claim 10
Dependent Claim
31 words
A launch tube window, as claimed in claim 5, wherein: said window has a thickness such that said window ruptures upon exposure to a pressure of more than about 25 psi.
Claim 11
Dependent Claim
142 words
A guided missile comprising: a missile propulsion system for moving the missile in a controllable direction; an optical guidance system operably connected to said propulsion system for controlling said direction of said movement; a dome covering at least a portion of said optical guidance system, the dome comprising a transparent, sintered polycrystalline body comprising magnesia-alumina spinel, having a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 0.4 microns and 0.5 microns of at least about 82%, at all wavelengths in the wavelength range between 3.0 microns and 4.0 microns of at least about 81%, and at all wavelengths in the wavelength range between 4 microns and 5 microns of at least about 76%, having a flexural strength of at least about 20,000 psi and having a knoop hardness of at least about 1350 kg mm -2 .
Claim 12
Dependent Claim
142 words
A guided missile comprising: a missile propulsion system for moving the missile in a controllable direction; an optical guidance system operably connected to said propulsion system for controlling said direction of said movement; a dome covering at least a portion of said optical guidance system, the dome comprising a transparent, sintered polycrystalline body comprising magnesia-alumina spinel, having a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 0.4 microns and 0.5 microns of at least about 82%, at all wavelengths in the wavelength range between 3.0 microns and 4.0 microns of at least about 81%, and at all wavelengths in the wavelength range between 4 microns and 5 microns of at least about 76%, having a flexural strength of at least about 20,000 psi and having a knoop hardness of at least about 1350 kg mm -2 .
Claim 13
Dependent Claim
124 words
A missile launch tube comprising: a tubular-shaped member having a sealable opening; a window attached to said tubular member in a position to seal said sealable opening, said window comprising a transparent, sintered polycrystalline body comprising magnesia-alumina spinel, having a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 0.4 microns and 0.5 microns of at least about 82%, at all wavelengths in the wavelength range between 3.0 microns and 4.0 microns of at least about 81%, and at all wavelengths in the wavelength range between 4 microns and 5 microns of at least about 76%, having a flexural strength of at least about 20,000 psi and having a knoop hardness of at least about 1350 kg mm -2 .
Claim 14
Dependent Claim
124 words
A missile launch tube comprising: a tubular-shaped member having a sealable opening; a window attached to said tubular member in a position to seal said sealable opening, said window comprising a transparent, sintered polycrystalline body comprising magnesia-alumina spinel, having a transmittance per 1.88 mm thickness at all wavelengths in the wavelength region between 0.4 microns and 0.5 microns of at least about 82%, at all wavelengths in the wavelength range between 3.0 microns and 4.0 microns of at least about 81%, and at all wavelengths in the wavelength range between 4 microns and 5 microns of at least about 76%, having a flexural strength of at least about 20,000 psi and having a knoop hardness of at least about 1350 kg mm -2 .
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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) | 1993-06-04 | 1993-12-04 | 1994-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-04 | 1997-12-04 | 1998-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-04 | 2001-12-04 | 2002-06-05 | $7700.00 | Window Closed / Lapsed |