Vehicle fuel economy by optimizing effective rolling tire resistance

Patent metadata

Field	Value
Publication number	US-9481415-B2
Application number	US-201214377067-A
Country	US
Kind code	B2
Filing date	Feb 10, 2012
Priority date	Feb 10, 2012
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

The subject matter of the present invention relates generally to a vehicle that has axles with tires mounted thereon with at least one axle that is a lift axle, and more specifically, to a method that optimizes the effective tire rolling resistance by adjusting the load on the tires, resulting in an improvement in the fuel economy of the vehicle. According to one embodiment, the method takes into consideration the rolling resistance characteristics of the tires placed onto the axles of the vehicle and provides an algorithm for optimizing their rolling resistance by raising or lowering the lift axle.

First claim

What is claimed is:

1. A vehicle suspension system for improving a fuel economy of a vehicle by optimizing effective tire rolling resistance, the vehicle suspension system comprising:
an at least one principal axle;
an at least one lift axle;
an at least one tire mounted on each of the axles;
an input device for entering instructions or information;
a memory for storing instructions, data or programs having algorithms;
load sensors for determining a load on each of the principal and lift axles;
a lift mechanism for lowering or raising the lift axle;
at least one processing device in communication with said input device, said memory, said load sensors, said lift mechanism, said at least one processing device configured for:
determining whether a total load carried by the vehicle is greater than a sum of maximum allowable axle load multiplied by a number of lift axles added to a minimum allowable axle load necessary multiplied by a number of principal axles; or
determining whether a total load carried by the vehicle is less than or equal to the sum of maximum allowable axle load multiplied by the number of lift axles added to the minimum allowable axle load necessary multiplied by the number of principal axles while also being greater than the total number of axles multiplied by the minimum allowable axle load necessary, or
determining whether the total load carried by the vehicle is less than or equal to a total number of axles multiplied by minimum allowable axle load necessary;
determining that the tires on a lift axle have lower rolling resistance characteristics than the tires on a principal axle; and
signaling to move said at least one lift axle so as to improve the fuel economy of said vehicle.

2. The vehicle suspension system of claim 1 , wherein the total load carried by the vehicle is determined to be greater than the sum of the maximum allowable axle load multiplied by the number of lift axles added to the minimum allowable axle load necessary multiplied by the number of principal axles, said vehicle suspension system further comprising signaling to move at least one lift axle so that a lift axle carries the maximum allowable axle load and a principal axle carries less load than one lift axle.

3. The vehicle suspension system of claim 1 , wherein the total load carried by the vehicle is determined to be less than or equal to the sum of maximum allowable axle load multiplied by the number of lift axles added to the minimum allowable axle load necessary multiplied by the number of principal axles while also being greater than the total number of axles multiplied by the minimum allowable axle load necessary, said vehicle suspension system further comprising signaling to move at least one lift axle so a principal axle carries a minimum axle load and a lift axle carries a load greater than a principal axle.

4. The vehicle suspension system of claim 1 , wherein the total load carried by the vehicle is determined to be less than or equal to the total number of axles multiplied by the minimum allowable axle load necessary, said vehicle suspension system further comprising signaling to move at least one lift axle so a principal axles carries a load that is the same as a load carried by a lift axle.

5. The vehicle suspension system of any of the preceding claims in which the total number of axles on the vehicle is two, wherein said at least one principal axle is a drive axle and said at least one lift axle is a tag axle, and wherein said at least one processing device of said vehicle suspension system is configured for:
determining whether the total load carried by the vehicle is greater than the sum of the maximum allowable axle load and minimum allowable axle load; or
determining whether the total load carried by the vehicle is less than or equal to the sum of maximum allowable axle load and minimum allowable axle load while also being greater than two multiplied by the minimum allowable axle load; or
determining whether the total load carried by the vehicle is less than or equal to two multiplied by the minimum allowable axle load while also being greater than or equal to the minimum allowable axle load.

6. The vehicle suspension system of claim 5 , wherein the total load carried by the vehicle is determined to be greater than the sum of maximum allowable axle load and the minimum allowable axle load, said vehicle suspension system further comprising signaling to move the tag axle until the axle load of the tag axle is the maximum allowable axle load and the axle load of the drive axle is equal to total load carried by the vehicle minus the maximum allowable axle load.

7. The vehicle suspension system of claim 5 , wherein the total load carried by the vehicle is determined to be less than or equal to the sum of maximum allowable axle load and minimum allowable axle load while also being greater than two multiplied by the minimum allowable axle load, said vehicle suspension system further comprising signaling to move the tag axle until the tag axle load equals the total load carried by the vehicle minus the minimum axle load and drive axle load equals the minimum allowable axle load.

8. The vehicle suspension system of claim 5 , wherein total load carried by the vehicle is determined to be less than or equal to two multiplied by the minimum allowable axle load while also being greater than or equal to the minimum allowable axle load, said vehicle suspension system further comprising signaling to move the tag axle until drive axle load equals the tag axle load.

9. A vehicle suspension system for improving a fuel economy of a vehicle by optimizing effective tire rolling resistance, the vehicle suspension system comprising:
an at least one principal axle;
an at least one lift axle;
an at least one tire mounted on each of the axles;
an input device for entering instructions or information;
a memory for storing instructions, data or programs having algorithms;
load sensors for determining a load on each of the principal and lift axles;
a lift mechanism for lowering or raising the lift axle;
at least one processing device in communication with said input device, said memory, said load sensors, said lift mechanism, said at least one processing device configured for:
determining whether a quantity of a total load carried by the vehicle minus a product of a maximum allowable axle load multiplied by a number of principal axles is greater than the minimum allowable axle load necessary multiplied by a number of lift axles; or
determining whether the quantity of the total load carried by the vehicle minus the product of the maximum allowable axle load multiplied by the number of principal axles is less than or equal to the product of minimum allowable axle load multiplied by the number of lift axles while at a same time the total load is greater than or equal to the total number of axles multiplied by the minimum allowable axle load necessary, or
determining whether the quantity of the total load carried by the vehicle is less than the total number of axles multiplied by the minimum allowable axle load necessary, or
determining whether the quantity of the load carried by the vehicle minus the product of the maximum allowable axle load multiplied by the number of lift axles is less than or equal to the product of the minimum allowable axle load multiplied by the number of principal axles while at the same time the total load is greater than or equal to the total number of axles multiplied by the minimum allowable axle load necessary;
determining that the tires on a lift axle have the same or higher rolling resistance characteristics than the tires on a principal axle; and
signaling to move said at least one lift axle so as t

Assignees

• Clayton William Bennett
• Bradley Calvin Rhett
• Michelin & Cie
• Michelin Rech Tech

Inventors

• Clayton William Bennett
• Bradley Calvin Rhett

Classifications

• B62D61/12 Primary

  with variable number of ground engaging wheels, e.g. with some wheels arranged higher than others, or with retractable wheels (for manoeuvring purposes only B60S) · CPC title

• B60G2400/60

  Load · CPC title

• B60G17/017

  characterised by their use when the vehicle is stationary, e.g. during loading, engine start-up or switch-off · CPC title

• B60G2204/47

  Means for retracting the suspension · CPC title

• B60G2400/61

  Load distribution · CPC title