US4368844A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Railroad support fabric
Assignee: EIDP Inc
•
Filing: 1981-10-06
•
Granted: 1983-01-18
•
Expires: 2001-10-06
Abstract
Abstract Railroad support fabric consisting essentially of three lamellae, two being of nonwoven polypropylene fibers, and the third being of nylon fibers, the nylon fiber lamella being sandwiched between the other lamellae, and railroad beds containing said support fabric.
Inventors
- 👤 Donald F. Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:56
CPC Classifications
E; E01; E01B; E01B1/00; E01B1/001; E01B2204/00; E01B2204/05; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/27; Y10T442/00; Y10T442/60; Y10T442/659; Y10T442/668
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
120 words
A laminar construction suitable for use as a geotextile support in a railroad bed consisting essentially of (1) a lamella of bonded nonwoven polypropylene fibers having a weight per square yard between about 6 and 18 oz, (2) a lamella of nylon fibers having a weight per square yard between about 2 and 6 oz, (3) and a lamella of bonded nonwoven polypropylene fibers having a weight per square yard between about 1 to 3 oz, said nylon lamella being located between said bonded nonwoven polypropylene fiber lamellae, said laminar construction being held together by localized areas of penetrations of fibers of one lamella into and/or through another, said laminar construction having a thickness of between 32 and 250 mils.
Claim 2
Dependent Claim
120 words
A laminar construction suitable for use as a geotextile support in a railroad bed consisting essentially of (1) a lamella of bonded nonwoven polypropylene fibers having a weight per square yard between about 6 and 18 oz, (2) a lamella of nylon fibers having a weight per square yard between about 2 and 6 oz, (3) and a lamella of bonded nonwoven polypropylene fibers having a weight per square yard between about 1 to 3 oz, said nylon lamella being located between said bonded nonwoven polypropylene fiber lamellae, said laminar construction being held together by localized areas of penetrations of fibers of one lamella into and/or through another, said laminar construction having a thickness of between 32 and 250 mils.
Claim 3
Dependent Claim
24 words
The laminar construction of claim 1 in which the polypropylene fiber lamellae are made up of fibers having a denier of 8 to 25.
Claim 4
Dependent Claim
24 words
The laminar construction of claim 2 in which the nylon fiber lamellae is made up of fibers having a denier of 1.5 to 5.
Claim 5
Dependent Claim
43 words
The laminar construction of claim 1 in which one of the polypropylene fiber lamellae weighs about 9 oz per square yard, and the other weighs about 1.9 oz square yard, and in which the nylon lamella weighs about 3.5 oz per square yard.
Claim 6
Dependent Claim
18 words
The laminar construction of claim 1 in which most of the polypropylene fibers are aligned in perpendicular directions.
Claim 7
Dependent Claim
22 words
The laminar construction of claim 1 in which the nylon fibers are randomly arranged in the plane of the nylon fiber lamella.
Claim 8
Dependent Claim
23 words
The laminar construction of claim 6 in which the nylon fibers have an average length in the range of 0.8 to 3.5 inches.
Claim 9
Dependent Claim
30 words
The laminar construction of claim 1 in which there are per square inch between 32 and 650 localized areas of penetrations of fibers of one lamella into and/or through another.
Claim 10
Dependent Claim
44 words
In a railroad bed which comprises a set of metal rails, mounted on railroad ties, said ties being supported by ballast, and said ballast being supported by earth, the improvement which comprises the laminate of claim 1 located between the ballast and the earth.
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) | 1986-01-17 | 1986-07-19 | 1987-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-17 | 1990-07-19 | 1991-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-17 | 1994-07-19 | 1995-01-18 | $7700.00 | Window Closed / Lapsed |