Patent US5230763A successfully refreshed from Google Patents.
US5230763A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for manufacturing a surface element to absorb electromagnetic waves
Assignee: Saint Gobain Isover SA France
•
Filing: 1990-08-24
•
Granted: 1993-07-27
•
Expires: 2010-08-24
Abstract
Abstract A process for the manufacture of a surface element in the form of a lamellar mat or sheet which can be used for the absorption of electromagnetic waves, in particularly radar waves. The surface element has a plurality of bands of mineral wool separated by bands of an electrically-conducting material and is manufactured on an industrial scale by stacking several mineral wool strips, sheets, or mats with intermediate layers of the electrically-conducting strips, sheets or mats into a pile. From this pile are then cut out pads composed of different bands which are laid out in such way that their cut faces become the large surface areas of the surface element. Then, each of the surface elements is clad on at least one face with a backing strip, for example of meshed aluminum foil, the main orientation of the fibers of the mineral wool being perpendicular to the backing strip.
Inventors
- 👤 Klaus Roth
- 👤 Joachim Mellem
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:30
CPC Classifications
H; H01; H01Q; H01Q17/00; H01Q17/005; E; E04; E04B; E04B1/00; E04B1/62; E04B1/74; E04B1/76; E04B2001/7683; Y; Y10; Y10S; Y10S428/00; Y10S428/92; Y10T; Y10T156/00; Y10T156/10; Y10T156/1052; Y10T156/1059; Y10T156/1062; Y10T156/1075
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
155 words
A process of manufacturing a surface element for absorption of electromagnetic waves, which comprises: alternately stacking a plurality of mineral wool layers having substantially parallel oriented fibers with intermediate bands of an electrically-conducting material into a pile; cutting the pile perpendicularly with respect to the orientation of said fibers into pads having faces formed by cutting the pile; laying the pads so that cut faces of the pads define a large surface area of the surface element; cladding backing strip means to two faces of the surface element wherein the step of cladding the backing strip means comprises cladding a metal foil to at least one face of the surface element for acting as an internal reflector of the electromagnetic waves; and cutting the surface element clad on both surfaces parallel to the two faces clad to the surface element in order to obtain two surface elements which are each clad on a single face.
Claim 2
Dependent Claim
155 words
A process of manufacturing a surface element for absorption of electromagnetic waves, which comprises: alternately stacking a plurality of mineral wool layers having substantially parallel oriented fibers with intermediate bands of an electrically-conducting material into a pile; cutting the pile perpendicularly with respect to the orientation of said fibers into pads having faces formed by cutting the pile; laying the pads so that cut faces of the pads define a large surface area of the surface element; cladding backing strip means to two faces of the surface element wherein the step of cladding the backing strip means comprises cladding a metal foil to at least one face of the surface element for acting as an internal reflector of the electromagnetic waves; and cutting the surface element clad on both surfaces parallel to the two faces clad to the surface element in order to obtain two surface elements which are each clad on a single face.
Claim 3
Dependent Claim
36 words
The process according to claim 1, wherein the step of cladding the backing strip means comprises cladding one face of the surface element with aluminum foil and cladding an opposite face with a non-woven fiber material.
Claim 4
Dependent Claim
24 words
The process according to claim 1, which comprises cutting the pile with a double-toothed sharp undulated cutter with a reciprocating movement of the cutter.
Claim 5
Dependent Claim
30 words
The process according to claim 3, which comprises driving the cutter so that the pads are cut from the pile by the cutter during vertical to-and-fro movement of the cutter.
Claim 6
Dependent Claim
26 words
The process according to claim 1, wherein cutting the pile comprises cutting the pile with a double-toothed undulated cutter with a reciprocating movement of the cutter.
Claim 7
Dependent Claim
24 words
The process according to claim 4, which comprises cutting the pile with a double-toothed sharp undulated cutter with a reciprocating movement of the cutter.
References Cited (Backward Citations)
US2036467A
Cited
US3315260A
Cited
GB1074899A
Cited
US3454947A
Cited
US3092203A
Cited
US3179317A
Cited
US3549449A
Cited
US3669789A
Cited
GB1397299A
Cited
US4025680A
Cited
EP0000378B1
Cited
US4327364A
Cited
JPS57183375A
Cited
US4381510A
Cited
US4581284A
Cited
US4514247A
Cited
CH664185A5
Cited
US4906504A
Cited
US5085931A
Cited
US5121122A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-07-26 | 1997-01-25 | 1997-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-07-26 | 2001-01-25 | 2001-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-07-26 | 2005-01-25 | 2005-07-27 | $7700.00 | Window Closed / Lapsed |