Patent US3671030A successfully refreshed from Google Patents.
US3671030A
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US
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Spring leaf and method of making
Assignee: NORTH AMERICAN ROCK CORP
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Filing: 1970-06-01
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Granted: 1972-06-20
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Expires: 1990-06-01
Abstract
Abstract A vehicle spring leaf has at least one of its opposite ends formed with closed eyes for connection to frame or shackle pivots. The spring leaf is slitted parallel to its length near the end and subjected to a deformation operation whereby an intermediate portion of the leaf is oppositely displaced with respect to the displacement of adjacent edge portions to provide opposed semi-cylindrical loops defining the eye. The deformation operation may occur either simultaneously with or subsequent to the slitting of the leaf.
Inventors
- 👤 John P Marion
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:25
CPC Classifications
F; F16; F16F; F16F1/00; F16F1/02; F16F1/18; F16F1/26; B; B21; B21D; B21D53/00; B21D53/88; B21D53/886; B60; B60G; B60G11/00; B60G11/02; B60G11/10; B60G11/12; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49609; Y10T29/49611
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
87 words
A metal spring leaf having at least one end formed with a closed eye structure by which said leaf may be secured to other structure, said closed eye structure consisting essentially of opposite edge portions similarly projecting a distance in one direction out of the plane of the leaf and an intermediate portion projecting oppositely substantially the same distance out of the planE of the leaf, said eye structure being positioned on said leaf such that said end has an imperforate end region outwardly of said eye.
Claim 2
Dependent Claim
87 words
A metal spring leaf having at least one end formed with a closed eye structure by which said leaf may be secured to other structure, said closed eye structure consisting essentially of opposite edge portions similarly projecting a distance in one direction out of the plane of the leaf and an intermediate portion projecting oppositely substantially the same distance out of the planE of the leaf, said eye structure being positioned on said leaf such that said end has an imperforate end region outwardly of said eye.
Claim 3
Dependent Claim
54 words
The spring leaf defined in claim 9, wherein said displaced edge portions have aligned internal cylindrical surfaces of equal curvature, and said oppositely displaced intermediate portion has an internal cylindrical surface of the same curvature, whereby said eye has a substantially continuous cylindrical inner periphery for pivotal connection to a vehicle frame or shackle.
Claim 4
Dependent Claim
34 words
The spring leaf defined in claim 9, wherein said displaced portions are arcuate and the internal bearing area of the intermediate portion equals the sum of the internal bearing areas of the edge portions.
Claim 5
Independent Claim
91 words
A method of making an integral eye structure at an end of a metal spring leaf which comprises the steps of longitudinally slitting the spring leaf adjacent but spaced from an end to provide opposite edge regions and at least one intermediate region separated from the spring end by an imperforate region, and oppositely displacing said edge regions and said intermediate region out of the plane of the leaf end substantially equal distances to form opposed loops substantially circumferentially defining said spring eye, said slitting and displacing steps being performed simultaneously.
Claim 6
Independent Claim
91 words
A method of making an integral eye structure at an end of a metal spring leaf which comprises the steps of longitudinally slitting the spring leaf adjacent but spaced from an end to provide opposite edge regions and at least one intermediate region separated from the spring end by an imperforate region, and oppositely displacing said edge regions and said intermediate region out of the plane of the leaf end substantially equal distances to form opposed loops substantially circumferentially defining said spring eye, said slitting and displacing steps being performed simultaneously.
Claim 7
Dependent Claim
93 words
An elongate metal load bearing member having at least one end formed in a flat configuration with a closed eye structure by which said member may be secured to other structure, said closed eye structure consisting essentially of opposite edge portions similarly projecting a distance in one direction out of the plane of the member and an intermediate portion projecting oppositely substantially the same distance out of the plane of the member, said eye structure being positioned on said member such that said end has an imperforate end region outwardly of said eye.
Claim 8
Dependent Claim
93 words
An elongate metal load bearing member having at least one end formed in a flat configuration with a closed eye structure by which said member may be secured to other structure, said closed eye structure consisting essentially of opposite edge portions similarly projecting a distance in one direction out of the plane of the member and an intermediate portion projecting oppositely substantially the same distance out of the plane of the member, said eye structure being positioned on said member such that said end has an imperforate end region outwardly of said eye.
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) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |