US3913938A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-levelling vehicle suspension system
Assignee: Nissan Motor Co Ltd
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Filing: 1974-07-03
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Granted: 1975-10-21
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Expires: 1994-07-03
Abstract
Abstract A self-levelling suspension system of an automotive vehicle, comprising at least one hydropneumatic suspension unit which is contractable and extendible in accordance with a load on a vehicle body, and an electrically operated hydraulic fluid control arrangement which is operative to provide in the suspension unit a first condition to maintain a self-levelling function, a second condition to cause the suspension unit to lose its self-levelling function and to merely act as a shock absorber, and a third condition in which the fluid in the suspension unit is increased beyond a level available for the self-levelling operation so that the suspension unit can be utilized as a vehicle jack-up device. The second condition of the suspension unit is achieved when the vehicle must take a meandering path or when the vehicle sideways rolls or sways.
Inventors
- 👤 Hiroshi Aikawa
- 👤 Naganori Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:39
CPC Classifications
B; B60; B60G; B60G17/00; B60G17/02; B60G17/033; B60G17/015; B60G17/0152; B60G17/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
389 words
In a self-levelling suspension system for an automotive vehicle including at least one hydropneumatic suspension unit actuated by a fluid pressure for adjusting the vertical position of the suspended portion of the vehicle body, an operating fluid supply line for providing communication between the suspension unit and a source of operating fluid for feeding the operating fluid to the suspension unit from the fluid source when open, a fluid discharge line which leads from the suspension unit for discharging the fluid from the suspension unit when open, a first valve means disposed in the fluid supply line for shutting off the fluid supply line when actuated, a second valve means disposed in the fluid discharge line for shutting off the fluid discharge line when actuated, and control means responsive to side roll of the vehicle body for actuating the first and second valve means to close the fluid supply and discharge lines in response to a vehicle roll angle larger than a predetermined limit, the improvement that said second valve means has first and second valve actuating means and which further comprises an auxiliary operating fluid supply line for providing communication between the source of the operating fLuid and the fluid discharge line through said second valve means, said second valve means having a first position to open the fluid discharge line and to close the auxiliary operating fluid supply line, a second position to close both of the fluid discharge line and the auxiliary operating fluid supply line, and a third position to close the fluid discharge line and to provide communication between the fluid discharge line and the auxiliary operating fluid supply line, the second valve means being in the first position when both of the first and second valve actuating means are inoperative, in the second position when the first valve actuating means is actuated, and in the third position when the second valve actuating means is actuated, and said control means responsive to side roll of the vehicle body and including a switch means having a first position to enable the first valve means and the first valve actuating means of the second valve means to be actuated in response to vehicle roll angle larger than a predetermined limit and a second position to actuate the second valve actuating means of the second valve means.
Claim 2
Dependent Claim
389 words
In a self-levelling suspension system for an automotive vehicle including at least one hydropneumatic suspension unit actuated by a fluid pressure for adjusting the vertical position of the suspended portion of the vehicle body, an operating fluid supply line for providing communication between the suspension unit and a source of operating fluid for feeding the operating fluid to the suspension unit from the fluid source when open, a fluid discharge line which leads from the suspension unit for discharging the fluid from the suspension unit when open, a first valve means disposed in the fluid supply line for shutting off the fluid supply line when actuated, a second valve means disposed in the fluid discharge line for shutting off the fluid discharge line when actuated, and control means responsive to side roll of the vehicle body for actuating the first and second valve means to close the fluid supply and discharge lines in response to a vehicle roll angle larger than a predetermined limit, the improvement that said second valve means has first and second valve actuating means and which further comprises an auxiliary operating fluid supply line for providing communication between the source of the operating fLuid and the fluid discharge line through said second valve means, said second valve means having a first position to open the fluid discharge line and to close the auxiliary operating fluid supply line, a second position to close both of the fluid discharge line and the auxiliary operating fluid supply line, and a third position to close the fluid discharge line and to provide communication between the fluid discharge line and the auxiliary operating fluid supply line, the second valve means being in the first position when both of the first and second valve actuating means are inoperative, in the second position when the first valve actuating means is actuated, and in the third position when the second valve actuating means is actuated, and said control means responsive to side roll of the vehicle body and including a switch means having a first position to enable the first valve means and the first valve actuating means of the second valve means to be actuated in response to vehicle roll angle larger than a predetermined limit and a second position to actuate the second valve actuating means of the second valve means.
Claim 3
Dependent Claim
168 words
A self-levelling suspension system as claimed in claim 1, in which said control means further includes an inclination sensing means responsive to a vehicle roll angle for producing an output voltage proportional to the detected vehicle roll angle, an integrating circuit for integrating the output voltage of the sensing means with respect to time for producing an integrated output voltage, a voltage dividing curcuit for producing an output voltage proportional to the integrated output voltage, and a switching circuit connected to an output terminal of the voltage dividing circuit and electrically connected to said first valve means and said first valve actuating means of the second valve means for maintaining the first valve actuating means of the second valve means inoperative when the output voltage from the voltage dividing circuit is lower than a predetermined level and actuating the first valve means and the first valve actuating means of the second valve means when the output voltage from the voltage dividing circuit is higher than the predetermined level.
Claim 4
Dependent Claim
36 words
A self-levelling suspension system as claimed in claim 2, in which said control means further includes short-circuiting means for making a short circuit between an output terminal of the integrating circuit and ground when manually actuated.
Claim 5
Dependent Claim
24 words
A self-levelling suspension system as claimed in claim 3, in which said switch means has a third position to actuate said short circuiting means.
References Cited (Backward Citations)
US3666286A
Cited
US3683818A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |