US3873121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydropneumatic suspension unit for motor vehicle
Assignee: Nissan Motor Co Ltd
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Filing: 1973-01-12
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Granted: 1975-03-25
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Expires: 1993-01-12
Abstract
Abstract A hydropneumatic suspension unit adapted to be mounted between a wheel supporting means and a body of a wheeled vehicle for maintaining the vehicle body at a substantially constant level irrespective of weight and load of the vehicle. The hydropneumatic suspension unit includes a cylinder having a cylinder head and a cylinder chamber filled with a hydraulic fluid under pressure and connected to the body of the motor vehicle, and a piston slidably accommodated in the cylinder chamber and connected to the wheel supporting means. The hydropneumatic suspension unit also includes a vehicle level adjusting device having a floating piston slidably received in an axial bore formed in the cylinder head and movable to different positions for controlling fluid communication between said cylinder chamber and either an inlet or an outlet. A piston chamber is defined by an end wall of the axial bore and an upper face of the floating piston. This piston chamber is brought into fluid communication with the cylinder chamber by means of a hydraulic fluid passageway formed in the cylinder head which hydraulic fluid passageway is larger in cross section that an orifice formed in the floating piston and which is opened when either one of the inlet and outlet is opened by the floating piston.
Inventors
- 👤 Naganori Ito
- 👤 Hiroshi Aikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:12
CPC Classifications
B; B60; B60G; B60G17/00; B60G17/02; B60G17/033; B60G17/04; B60G17/048
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
375 words
A hydropneumatic suspension unit adapted to mounted between a vehicle body and wheel supporting means, comprising a cylinder defining therein a cylinder chamber filled with pressurized fluid, the volume of said cylinder chamber being variable in response to variations in the load of a vehicle body to allow retraction and extension of said suspension unit, said cylinder chamber being fluidly communicable with a pressurized fluid source and with a drain, valve means disposed between said source and said cylinder chamber and between said drain and said cylinder chamber to normally block fluid communication therebetween and operable in response to increases and reductions in the load of said vehicle body to extablish fluid communication between said source and said cylinder chamber to cause supply of pressurized fluid thereinto for extension of said suspension unit and between said drain and said cylinder chamber to cause discharge of fluid therefrom for retraction of said suspension unit thereby maintaining the height of said vehicle body substantially constant independently of the load of said vehicle body, a hollow member, a floating piston slidably disposed in said hollow member, said hollow member having therein a first fluid chamber at one end of said floating piston and a second fluid chamber at the other end of said floating piston, said floating piston having formed therethrough a restricted passageway interconncecing said first and second fluid chambers, said hollow member having formed therein a bypass passageway opening at one end into said first fluid chamber and fluidly communicable at the other end with said second fluid chamber, said floating piston controlling fluid communication between said bypass passageway and said second fluid chamber and being held in a neutral position to block said fluid communication therebetween when said valve means blocks said fluid communication between said cylinder chamber and said source and between said cylinder chamber and said drain and being movable to first and second operative positions to extablish said fluid communication between said bypass passageway and said second fluid chamber when said valve means establishes said fluid communication between said source and said cylinder chamber and between said drain and said cylinder chamber, and two biasing means urging said floating piston in opposite directions to resiliently hold the same in said neutral position.
Claim 2
Dependent Claim
375 words
A hydropneumatic suspension unit adapted to mounted between a vehicle body and wheel supporting means, comprising a cylinder defining therein a cylinder chamber filled with pressurized fluid, the volume of said cylinder chamber being variable in response to variations in the load of a vehicle body to allow retraction and extension of said suspension unit, said cylinder chamber being fluidly communicable with a pressurized fluid source and with a drain, valve means disposed between said source and said cylinder chamber and between said drain and said cylinder chamber to normally block fluid communication therebetween and operable in response to increases and reductions in the load of said vehicle body to extablish fluid communication between said source and said cylinder chamber to cause supply of pressurized fluid thereinto for extension of said suspension unit and between said drain and said cylinder chamber to cause discharge of fluid therefrom for retraction of said suspension unit thereby maintaining the height of said vehicle body substantially constant independently of the load of said vehicle body, a hollow member, a floating piston slidably disposed in said hollow member, said hollow member having therein a first fluid chamber at one end of said floating piston and a second fluid chamber at the other end of said floating piston, said floating piston having formed therethrough a restricted passageway interconncecing said first and second fluid chambers, said hollow member having formed therein a bypass passageway opening at one end into said first fluid chamber and fluidly communicable at the other end with said second fluid chamber, said floating piston controlling fluid communication between said bypass passageway and said second fluid chamber and being held in a neutral position to block said fluid communication therebetween when said valve means blocks said fluid communication between said cylinder chamber and said source and between said cylinder chamber and said drain and being movable to first and second operative positions to extablish said fluid communication between said bypass passageway and said second fluid chamber when said valve means establishes said fluid communication between said source and said cylinder chamber and between said drain and said cylinder chamber, and two biasing means urging said floating piston in opposite directions to resiliently hold the same in said neutral position.
Claim 3
Dependent Claim
30 words
A hydropneumatic suspension unit as claimed in claim 1, in which said hollow member is integral with said cylinder and said first fluid chamber is aligned with said cylinder chamber.
Claim 4
Dependent Claim
77 words
Hydropneumatic suspension unit as claimed in claim 2, in which said floating piston has formed therein first and second annular recesses and a bore opening into said second fluid chamber and communicating with said first and second annular recesses, said first annular recess communicating with said bypass passageway when said floating piston is in said second operative position, said second annular recess communicating with said bypass passageway when said floating piston is in said first operative position.
Claim 5
Dependent Claim
104 words
A hydropneumatic suspension unit as claimed in claim 3, in which said hollow member has formed therein an inlet passageway communicating with said pressurized fluid source, an outlet passageway communicating with said drain, and a branch passageway communicating with said bypass passageway, and in which said valve means comprises said floating Piston, said floating piston having further formed therein a third annular recess which provides fluid communication between said inlet passageway and said branch passageway when said floating piston is in said first operative position and between said outlet passageway and said branch passageway when said floating piston is in said second operative position.
Claim 6
Dependent Claim
121 words
A hydropneumatic suspension unit as claimed in claim 3, in which said hollow member has formed therein an inlet passageway communicating with said pressurized fluid source and opening into said first fluid chamber and an outlet passageway communicating with said drain and opening into said first fluid chamber, and in which said valve means comprises a first valve member disposed in said inlet passageway to normally block the same and a second valve member disposed in said outlet passageway to normally block the same, said first and second valve members being operated by means on said floating piston to positions to open said inlet and outlet passageways, when said floating piston is moved to said first and second operative positions, respectively.
Claim 7
Dependent Claim
122 words
A hydropneumatic suspension unit as claimed in claim 2, in which said bypass passageway is openable at said other end into said second fluid chamber, and in which said hollow member has further formed therein a second bypass passageway openable at one end into said first fluid chamber and opening at the other end into said second fluid chamber, said floating piston closing said other end of said first bypass passageway and said one end of said second bypass passageway when it is in said neutral position and opening said other end of said first bypass passageway when it is in said second operative position and said one end of said second bypass passageway when it is in said first operative position.
Claim 8
Dependent Claim
118 words
A hydropneumatic suspension unit as claimed in claim 6, in which said hollow member has formed therein an inlet passageway communicating with said pressurized fluid source and opening into said second fluid chamber and an outlet passageway communicating with said drain and opening into said second fluid chamber, and in which said valve means comprises a first valve member disposed in said inlet passageway to normally block the same and second valve member disposed in said outlet passageway to normally block the same, said first and second valve members being operated by said floating piston to positions to open said inlet and outlet passageways, when said floating piston is moved to said first and second operative positions, respectively.
Claim 9
Dependent Claim
106 words
A hydropneumatic suspension unit as claimed in claim 1, in which said hollow member has formed therein an inlet passageway communicating with said pressurized fluid source, an outlet passageway communicating with said drain and a fourth passageway communicating with said cylinder chamber, and in which said valve means comprises said floating piston, said floating piston having formed therein an annular recess which provides fluid communication between said inlet passageway and said fourth passageway when said floating piston is in said first operative position and which provides fluid communication between said outlet passageway and said fourth passageway when said floating piston is in said second operative position.
Claim 10
Dependent Claim
122 words
A hydropneumatic suspension unit as claimed in claim 8, in which said bypass passageway is openable at said other end into said second fluid chamber, and in which said hollow member has further formed therein a second bypass passageway openable at one end into said first fluid chamber and opening at the other end into said second fluid chamber, said floating piston closing said other end of said first bypass passageway and said one end of said second bypass passageway when it is in said neutral position and opening said other end of said first bypass passageway when it is in said first operative position and said one end of said second bypass passageway when it is in said second operative position.
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) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |