US3556504A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Suspension systems
Assignee: Gloucester Railway Carriage and Wagon Co Ltd
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Filing: 1968-07-22
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Granted: 1971-01-19
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Expires: 1988-07-22
Abstract
Abstract A spring unit for a vehicle suspension system, the unit comprising two springs so arranged that in the pretare condition they operate in series and in the gross load condition operate in parallel.
Inventors
- 👤 Frederick William Sinclair
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 08:59
CPC Classifications
F; F16; F16F; F16F3/00; F16F3/02; F16F3/04; B; B61; B61F; B61F5/00; B61F5/02; B61F5/04; B61F5/06
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
134 words
A spring unit for a vehicle suspension system and adapted to be mounted between sprung and unsprung parts of the vehicle, the unit comprising inner and outer springs disposed coaxially one within the other, and inner and outer telescopic abutment members each formed with a spring abutment and which interengage to define a maximum telescopic extension of said members, opposite outer ends of said springs being adapted respectively to engage said vehicle parts and the other ends of said springs respectively engaging the spring abutments of the telescopic members, whereby in a pretare condition of the vehicle said maximum telescopic extension of the abutment members results in the springs acting in series and in a gross load condition of the vehicle telescoping of the abutment members results in the two springs acting in parallel.
Claim 2
Dependent Claim
134 words
A spring unit for a vehicle suspension system and adapted to be mounted between sprung and unsprung parts of the vehicle, the unit comprising inner and outer springs disposed coaxially one within the other, and inner and outer telescopic abutment members each formed with a spring abutment and which interengage to define a maximum telescopic extension of said members, opposite outer ends of said springs being adapted respectively to engage said vehicle parts and the other ends of said springs respectively engaging the spring abutments of the telescopic members, whereby in a pretare condition of the vehicle said maximum telescopic extension of the abutment members results in the springs acting in series and in a gross load condition of the vehicle telescoping of the abutment members results in the two springs acting in parallel.
Claim 3
Dependent Claim
39 words
A spring unit according to claim 1, wherein the two telescopic abutment members are respectively adapted to engage the sprung and unsprung parts of the vehicle so as to be movable therewith when the springs are acting in parallel.
Claim 4
Dependent Claim
44 words
A spring unit according to claim 2, wherein one only of the telescopic abutment members is adapted to be engaged with one of said vehicle parts in the tare condition of the vehicle to render one of said springs alone operative in that condition.
Claim 5
Dependent Claim
48 words
A spring unit according to claim 1, wherein the outer telescopic abutment member has an external end flange against which the inner end of the outer spring bears and the inner telescopic member has an internal end flange against which the inner end of the inner spring bears.
Claim 6
Dependent Claim
42 words
A spring unit according to claim 1, wherein an inner end flange on the inner telescopic member provides the inner end abutment for the inner spring and also engages the outer telescopic member to define the maximum extension of the telescopic members.
Claim 7
Dependent Claim
41 words
A bogie for a rail vehicle and incorporating two spaced side frames with a transverse bolster each end of which is supported in the corresponding frame on a plurality of spring units each of which is in accordance with claim 1.
Claim 8
Dependent Claim
34 words
A spring unit according to claim 4, wherein the inner and outer telescopic members are each tubular and respectively have further end flanges which interengage to define the maximum extension of the telescopic members.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |