US3603611A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vehicle-levelling systems
Assignee: Girling Ltd
•
Filing: 1969-05-19
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Granted: 1971-09-07
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Expires: 1989-05-19
Abstract
Abstract This invention relates to a pneumatically operable automatic levelling system for a motor vehicle including a motor/compressor/dryer unit, a reservoir for storing air under pressure, at least one vehicle-levelling strut, a valve for controlling the flow of air under pressure to and from the strut to maintain the vehicle level, and a pressure-sensitive switch for switching off the motor of the unit when the pressure of air in the reservoir reaches a preset upper limit.
Inventors
- 👤 Graham J Wenham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:29
CPC Classifications
B; B60; B60G; B60G17/00; B60G17/02; B60G17/04
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
75 words
A pneumatically operable, automatic leveling system for a motor vehicle, comprising a motor/compressor/dryer unit, a reservoir for storing air under pressure, one or more vehicle leveling struts, a valve for controlling the flow of air under pressure to and from the strut or struts to maintain the vehicle level, and a pressure-sensitive switch means for switching off the motor of said unit when the pressure of air in the reservoir reaches a preset upper limit.
Claim 2
Dependent Claim
75 words
A pneumatically operable, automatic leveling system for a motor vehicle, comprising a motor/compressor/dryer unit, a reservoir for storing air under pressure, one or more vehicle leveling struts, a valve for controlling the flow of air under pressure to and from the strut or struts to maintain the vehicle level, and a pressure-sensitive switch means for switching off the motor of said unit when the pressure of air in the reservoir reaches a preset upper limit.
Claim 3
Dependent Claim
36 words
A system according to claim 1, wherein the switch means after switching off the motor is operable to permit the pressure in the reservoir to drop by a preset amount before switching the motor on again.
Claim 4
Dependent Claim
21 words
A system according to claim 2, wherein the switch means includes a constant high hysteresiS switch mechanism incorporating Bourdon tube actuation.
Claim 5
Dependent Claim
14 words
A system according to claim 2, wherein the preset pressure drop is 25-30 p.s.i.
Claim 6
Dependent Claim
31 words
A system according to claim 1, wherein the valve is operable to ensure that the pressure of air in the strut or struts does not fall below a specified minimum valve.
References Cited (Backward Citations)
US2939723A
Cited
US3037788A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-06 | 1975-03-08 | 1975-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-06 | 1979-03-08 | 1979-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-06 | 1983-03-08 | 1983-09-07 | $7700.00 | Window Closed / Lapsed |