US4688778A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plastic leaf spring
Assignee: Isosport Verbundbauteile GmbH
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Filing: 1983-09-29
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Granted: 1987-08-25
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Expires: 2003-09-29
Abstract
Abstract A plastic leaf spring for motor vehicles comprising a plurality of cured durometic plastic strips reinforced with high strength fibers aligned substantially in the direction of the maximum elongation or compression of the fibers occurring under spring load at least in essential resilient regions of the spring, the resilient regions being the strips bonded together by an adhesive and eventually also being bonded to another element and a process for its preparation.
Inventors
- 👤 Herbert Woltron
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:46
CPC Classifications
B; B29; B29C; B29C43/00; B29C43/32; B29C70/00; B29C70/04; B29C70/06; B29C70/08; B29C70/086; B29C70/28; B29C70/40; B29C70/42; B29C70/46; B29D; B29D99/00; B29D99/0003; B29D99/0007; F; F16; F16F; F16F1/00; F16F1/02; F16F1/18; F16F1/36; F16F1/366; F16F1/368; B29K; B29K2105/00; B29K2105/04; B29L; B29L2031/00; B29L2031/774; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1043; Y10T156/1044; Y10T156/1052; Y10T156/1062; Y10T156/1075
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
84 words
A plastic leaf spring for vehicles comprising a plurality of more than three cured duromeric plastic ribbon-like strips reinforced with high strength fibers aligned substantially in the direction of the maximum elongation or compression of the strips occurring under spring load at least in essential resilient regions of the spring, wherein the said resilient regions being said strips of at least 0.8 mm thickness bonded together via layers of adhesive, said resilient regions eventually also being bonded via layers of adhesive to another element.
Claim 2
Dependent Claim
84 words
A plastic leaf spring for vehicles comprising a plurality of more than three cured duromeric plastic ribbon-like strips reinforced with high strength fibers aligned substantially in the direction of the maximum elongation or compression of the strips occurring under spring load at least in essential resilient regions of the spring, wherein the said resilient regions being said strips of at least 0.8 mm thickness bonded together via layers of adhesive, said resilient regions eventually also being bonded via layers of adhesive to another element.
Claim 3
Dependent Claim
112 words
A plastic leaf spring of oblong shape with a viable longitudinal thickness for vehicles comprising a plurality of more than three cured duromeric plastic ribbon-like strips reinforced with high strength fibers aligned substantially in the direction of maximum elongation or compression of the strips occurring under spring load in the resilient regions of the spring, wherein a sole resilient region is formed by said strips of at least 0.8 mm thickness bonded together via layers of adhesive, whereby in said sole resilient region the outermost strips extend over the entire length of this resilient region and others of said strips have different lengths and are shorter than the said sole resilient region.
Claim 4
Dependent Claim
112 words
A plastic leaf spring of oblong shape with a viable longitudinal thickness for vehicles comprising a plurality of more than three cured duromeric plastic ribbon-like strips reinforced with high strength fibers aligned substantially in the direction of maximum elongation or compression of the strips occurring under spring load in the resilient regions of the spring, wherein a sole resilient region is formed by said strips of at least 0.8 mm thickness bonded together via layers of adhesive, whereby in said sole resilient region the outermost strips extend over the entire length of this resilient region and others of said strips have different lengths and are shorter than the said sole resilient region.
Claim 5
Dependent Claim
30 words
A leaf spring of claim 1 having two resilient regions bonded on either side of a core made of an elastomeric resin and of fibrous material embedded in this resin.
Claim 6
Dependent Claim
23 words
A leaf spring of claim 1 wherein the majority of the strips have the reinforcement fibers extending exclusively lengthwise of the leaf spring.
Claim 7
Dependent Claim
10 words
The spring of claim 4 wherein the strips are prestressed.
Claim 8
Dependent Claim
32 words
A leaf spring of claim 1 wherein a minority of strips have reinforcement fibers whose axes include an angle of 5° to 90° with respect to the lengthwise direction of the spring.
Claim 9
Dependent Claim
11 words
The spring of claim 6 wherein the angle is 90° C.
Claim 10
Dependent Claim
12 words
The spring of claim 1 wherein the adhesive is a duromeric resin.
Claim 11
Dependent Claim
16 words
The spring of claim 1 wherein the fibers are in the form of a fiber fabric.
Claim 12
Dependent Claim
21 words
The spring of claim 1 wherein the adhesive is based on the same curable duromeric plastic as used in the strips.
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Cited
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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) | 1990-08-24 | 1991-02-23 | 1991-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-24 | 1995-02-23 | 1995-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-24 | 1999-02-23 | 1999-08-25 | $7700.00 | Window Closed / Lapsed |