Electronic suspension and level control system for recreational vehicles

• US 7,066,474 B2
• Filed: 03/14/2003
• Issued: 06/27/2006
• Est. Priority Date: 03/14/2003
• Status: Active Grant

• Current Assignee: Valid Manufacturing Ltd.
• Original Assignee: Valid Manufacturing Ltd.
• Inventors: Hiebert, Grant W., Fenkhuber, Jack W., Clancy, Gerald W.
• Primary Examiner(s): Ilan, Ruth
• Application Number:
  US10/387,418
• Publication Number:
  US 20040178587A1
• Time in Patent Office: 1,201 Days
• Field of Search: 280/5.514, 280/6.153, 280/6.157, 280/5.513, 280/5.507, 280/5.508, 280/5.512, 280/124.16, 280/5.515, 701/37
• US Class Current: 280/6.153
• CPC Class Codes: B60G 17/0155 pneumatic unit
• CPC Class Codes: B60G 17/0523 Regulating distributors or valves for pneumatic springs
• CPC Class Codes: B60G 2400/0511 Roll angle
• CPC Class Codes: B60G 2400/0512 Pitch angle
• CPC Class Codes: B60G 2400/1042 using at least two sensors
• CPC Class Codes: B60G 2400/1062 using at least two sensors
• CPC Class Codes: B60G 2400/252 vertical
• CPC Class Codes: B60G 2500/203 Distributor valve units comprising several elements, e.g. valves, pump or accumulators
• CPC Class Codes: B60G 2500/204 Pressure regulating valves for air-springs
• CPC Class Codes: B60G 2500/302 using distributor valves
• CPC Class Codes: B60G 2600/02 Retarders, delaying means, dead zones, threshold values, cut-off frequency, timer interruption
• CPC Class Codes: B60G 2600/20 Manual control or setting means
• CPC Class Codes: B60G 2600/82 duty rate function
• CPC Class Codes: B60G 2800/012 Rolling condition
• CPC Class Codes: B60G 2800/014 Pitch; Nose dive
• CPC Class Codes: B60G 2800/702 Improving accuracy of a sensor signal
• CPC Class Codes: B60G 2800/912 Attitude Control; levelling control

Abstract

The suspension and level control system for vehicles includes, so as to independently control inflation and deflation of left and right front and rear air-springs, corresponding left and right front and rear pneumatic circuits in fluid communication with a pressurized air source. Each air-spring may have at least one air ride cushion reservoir mounted in a parallel pneumatic circuit in parallel fluid communication with the air-spring. Each pneumatic circuit includes a selectively actuable valve for selectively passing pressurized air from the air source into the corresponding parallel pneumatic circuit to selectively inflate the corresponding air-spring thereby raising a corresponding corner of the vehicle; and for selectively venting pressurized air from the corresponding parallel pneumatic circuit to selectively deflate the corresponding air-spring, thereby lowering a corresponding corner of the vehicle. An anti-dive valve in each circuit having a cushion reservoir selectively isolates the corresponding reservoir upon a control signal from a processor triggered by input from accelerometers.

Claims

1. A suspension or level control system for a vehicle comprising:

left and right parallel pneumatic circuits, said left and right parallel pneumatic circuits parallel to each other and mounted to a chassis of the vehicle so as to extend to opposite sides of the vehicle, said circuits in fluid communication with a pressurized air source so as to independently control inflation and deflation of corresponding left and right air-springs of the vehicle, and wherein each said pneumatic circuit includes a selectively actuable height control valves for;

a) selectively passing pressurized air from said air source into the corresponding said parallel pneumatic circuit to selectively inflate the corresponding said air-spring thereby raising a corresponding corner of said chassis; and

,

b) selectively venting pressurized air from the corresponding said parallel pneumatic circuit to selectively deflate the corresponding said air-spring, thereby lowering a corresponding corner of said chassis,

at least one accelerometer on the vehicle providing acceleration data indicating tilt of the vehicle when the vehicle is static and dynamic acceleration including tilt when the vehicle is moving, and means for monitoring said acceleration data cooperating with said selectively actuable height control valves so as to selectively actuate said passing pressurized air or said venting pressurized air.

2. The system of claim 1 wherein said at least one accelerometer is mounted to said chassis and senses a pitch angle and/or a roll angle of said chassis about corresponding respective lateral and/or longitudinal axes of said chassis.

3. The system of claim 2 wherein data from said at least one accelerometer corresponding to at least said pitch angle and/or said roll angle of said chassis is communicated by communication means to a processor, and wherein said processor is programmed to communicate a control signal by said communication means to said height control valves to thereby actively urge said chassis to level by lowering a high corner of the vehicle and/or by raising a low corner of the vehicle so that at least said pitch angle and/or said roll angle return to within a preset limit range.

4. The system of claim 3 wherein each air-spring of said left and right air-springs has at least one air ride cushion reservoir mounted in a corresponding said parallel pneumatic circuit in parallel fluid communication with said each air-spring.

5. The system of claim 4 further comprising a selectively actuable anti-dive valve mounted into each said parallel pneumatic circuit so as to control fluid communication between the corresponding said air-spring and its corresponding said air ride cushion reservoir.

6. The system of claim 5 wherein said processor communicates by said communication means with each said anti-dive valve to selectively isolate each said reservoir from the corresponding said pneumatic circuit in response to said data from said at least one accelerometer indicating longitudinal and/or lateral accelerations of said chassis exceeding preset threshold acceleration values.

7. The system of claim 6 wherein said processor determines corresponding pitch and/or roll rates corresponding to said accelerations and compares said pitch and/or roll rates to preset threshold pitch and/or roll rate values to predict diving of the vehicle during manoeuvring.

8. The system of claim 3 wherein said left and right air-springs include rear left and rear right air-springs and front left and front right air-springs mounted to said chassis, said front left and front right air-springs in fluid communication with said air source via a single front pneumatic circuit mounted to said chassis, wherein said vehicle is selectively levelable upon selective independent inflation or deflation of said left rear air-spring or said right rear air-spring or said front left or front right air-springs parallel to a corresponding three axes.

9. The system of claim 8 wherein each pneumatic circuit of said left rear and right rear pneumatic circuits and said front pneumatic circuit has an air ride cushion reservoir mounted in parallel fluid communication therewith.

10. The system of claim 9 further comprising a selectively actuable anti-dive valve mounted into each said parallel pneumatic circuit so as to control fluid communication between the corresponding said air-spring and its corresponding said air ride cushion reservoir.

11. The system of claim 10 wherein said processor communicates by said communication means with each said anti-dive valve to selectively isolate each said reservoir from the corresponding said pneumatic circuit in response to said data from said at least one accelerometer indicating longitudinal and/or lateral accelerations of said chassis exceeding preset threshold acceleration values.

12. The system of claim 11 wherein said processor determines corresponding pitch and/or roll rates corresponding to said accelerations and compares said pitch and/or roll rates to preset threshold pitch and/or roll rate values to predict diving of the vehicle during manoeuvring.

13. The system of claim 8 wherein said three axes are vertical axes, one in each rear corner and one in the front of said vehicle.

14. The system of claim 3 wherein said left and right air-springs include front left and front right air-springs and wherein said left and right parallel pneumatic circuits include front left and front right pneumatic circuits, said front left air-spring mounted to said chassis in fluid communication with said air source via said front left pneumatic circuit mounted to said chassis, and said front right air-spring mounted to said chassis in fluid communication with said air source via said front right pneumatic circuit mounted to said chassis, wherein said vehicle is selectively levelable upon selective independent inflation or deflation of said air-springs parallel to a corresponding four axes.

15. The system of claim 14 wherein each pneumatic circuit of said parallel pneumatic circuits has an air ride cushion reservoir mounted in parallel fluid communication therewith.

16. The system of claim 15 further comprising a selectively actuable anti-dive valve mounted into each said parallel pneumatic circuit so as to control fluid communication between the corresponding said air-spring and its corresponding said air ride cushion reservoir.

17. The system of claim 16 wherein said processor communicates by said communication means with each said anti-dive valve to selectively isolate each said reservoir from the corresponding said parallel pneumatic circuit in response to said data from said at least one accelerometer indicating longitudinal and/or lateral accelerations of said chassis exceeding preset threshold acceleration values.

18. The system of claim 17 wherein said processor determines corresponding pitch and/or roll rates corresponding to said accelerations and compares said pitch and/or roll rates to preset threshold pitch and/or roll rate values to predict diving of the vehicle during manoeuvring.

19. The system of claim 14 wherein said four axes are vertical axes, one in each front and rear corner of said vehicle.