US3620334A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frictional-retarding means
Assignee: British Railways Board
•
Filing: 1968-06-26
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Granted: 1971-11-16
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Expires: 1988-06-26
Abstract
Abstract Improved frictional-retarding means containing at least one cast iron brake surface. The improvement consists in constructing said brake surface of a cast iron consisting essentially (i) of from 2 percent up to 5 percent by weight of phosphorus, (ii) silicon, and (iii) carbon, with the total of said silicon and carbon being less than 6 percent, and (iv) the remainder being essentially iron. Minor amounts of the impurities usually found in cast iron may be tolerated.
Inventors
- 👤 Eric Douglas Henley
- 👤 George Eden Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:04
CPC Classifications
C; C21; C21C; C21C7/00; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
15 words
The frictional-retarding means of claim 1 wherein said one brake surface is a brake drum.
Claim 2
Dependent Claim
16 words
The frictional retarding means of claim 1 wherein said one break surface is a brake disc.
Claim 3
Dependent Claim
16 words
The frictional-retarding means of claim 1 wherein said one brake surface is a railroad brake shoe.
Claim 4
Dependent Claim
18 words
The frictional-retarding means of claim 4 wherein the proportion of phosphorus is from 2.4- 5 percent by weight.
Claim 5
Dependent Claim
10 words
The frictional-retarding means of claim 5 containing 2.4 percent phosphorus.
Claim 6
Dependent Claim
10 words
The frictional-retarding means of claim 5 containing 3 percent phosphorus.
Claim 7
Dependent Claim
10 words
The frictional-retarding means of claim 5 containing 3.2 percent phosphorus.
Claim 8
Dependent Claim
10 words
The frictional-retarding means of claim 5 containing 4 percent phosphorus.
References Cited (Backward Citations)
US1527165A
Cited
US1690352A
Cited
GB463311A
Cited
US2402424A
Cited
US3193383A
Cited
US3318423A
Cited
US3533758A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |