초록

A trailer axle suspension system and a method of control. The trailer axle suspension system may be deflated when the trailer is approaching the dock and proximity of the trailer to the dock is within a predetermined limit.

대표청구항 ▼

1. A method of controlling a trailer axle suspension system of a vehicle comprising: assessing proximity of a trailer to a dock when a dock approach condition exists; anddeflating the trailer axle suspension system when the trailer is approaching the dock and proximity of the trailer to the dock is

1. A method of controlling a trailer axle suspension system of a vehicle comprising: assessing proximity of a trailer to a dock when a dock approach condition exists; anddeflating the trailer axle suspension system when the trailer is approaching the dock and proximity of the trailer to the dock is within a predetermined limit. 2. The method of claim 1 wherein deflating the trailer axle suspension system includes deflating an air spring of the trailer axle suspension system. 3. The method of claim 2 wherein the air spring is deflated before the trailer contacts the dock. 4. The method of claim 3 wherein the air spring is deflated at a fixed rate. 5. The method of claim 3 wherein the air spring is deflated at a variable rate based on a rate at which the trailer is approaching the dock. 6. The method of claim 2 wherein the air spring is inflated with a pressurized gas prior to releasing a parking brake and moving the trailer away from the dock. 7. The method of claim 1 wherein the dock approach condition exists when the trailer is moving in a reverse direction and the dock is detected with a dock proximity sensor. 8. The method of claim 7 wherein the dock proximity sensor is disposed proximate a rear end of the trailer that is disposed opposite a tractor to which the trailer is coupled. 9. The method of claim 1 wherein proximity of the trailer to the dock is within the predetermined limit when a predicted time until the trailer contacts the dock is less than a threshold time value. 10. The method of claim 1 wherein proximity of the trailer to the dock is within a predetermined limit when a distance between the trailer and the dock is not greater than a predetermined threshold distance value. 11. The method of claim 1 wherein a parking brake is set after the trailer axle suspension system is deflated and the trailer is stationary. 12. The method of claim 1 wherein a dock approach condition exists when the trailer is moving in a reverse direction. 13. The method of claim 12 wherein a dock approach condition exists when a tractor to which the trailer is coupled in a reverse gear. 14. The method of claim 13 wherein a dock approach condition exists when the tractor is moving in a reverse direction at a speed that is less than a threshold speed value.