Controlling weight allocation between truck axles

Patent metadata

Field	Value
Publication number	US-2016257355-A1
Application number	US-201615042910-A
Country	US
Kind code	A1
Filing date	Feb 12, 2016
Priority date	Mar 3, 2015
Publication date	Sep 8, 2016
Grant date	—

Abstract

In a truck vehicle, a controller controls a mechanism to apportion the sum total of weight borne by a tandem axle between a drive axle and a tag axle.

First claim

What is claimed is:

1 . A truck vehicle comprising:
a chassis comprising a chassis frame; steerable right and left front wheels suspended from the chassis frame; a tandem axle suspended from the chassis frame rearward of the front wheels and comprising a drive axle having drive wheels and a tag axle having non-drive wheels; a mechanism for apportioning the sum total of weight borne by the tandem axle between the drive axle and the tag axle; and a controller for controlling the mechanism to apportion a desired percentage of the sum total of weight borne by the tandem axle to one of the axles while forcing ride height of the tandem axle to conform to a desired ride height.

2 . The truck vehicle as set forth in claim 1 in which the controller controls the mechanism to apportion a desired percentage of the sum total of weight borne by the tandem axle to one of the axles as a function of a variable parameter related to vehicle operation.

3 . The truck vehicle as set forth in claim 2 in which the controller controls the mechanism to apportion a desired percentage of the sum total of weight borne by the tandem axle to one of the axles as a function of a travelling speed of the truck vehicle.

4 . The truck vehicle as set forth in claim 3 in which the controller controls the mechanism to apportion a maximum percentage of the sum total of weight borne by the tandem axle to the drive axle when travelling speed of the truck vehicle is within a low speed range between zero and an upper limit of the low speed range.

5 . The truck vehicle as set forth in claim 4 in which the controller controls the mechanism to apportion a maximum percentage of the sum total of weight borne by the tandem axle to the tag axle when travelling speed of the truck vehicle is within a high speed range greater than the upper limit of the low speed range.

6 . The truck vehicle as set forth in claim 5 in which the controller controls the mechanism, when travelling speed of the truck vehicle is within an intermediate speed range between the high speed range and the low speed range, to apportion to the tag axle less than the maximum percentage of the sum total of weight borne by the tandem axle when travelling speed of the truck vehicle is within the high speed range and to apportion to the drive axle less than the maximum percentage of the sum total of weight borne by the tandem axle when travelling speed of the truck vehicle is within the low speed range.

7 . The truck vehicle as set forth in claim 1 further comprising a fifth wheel supported on the chassis frame in overlying relation to the tandem axle, and further including a trailer coupled to the fifth wheel for towing by the truck vehicle with weight of the trailer bearing on the fifth wheel contributing to the sum total of weight borne by the tandem axle.

8 . The truck vehicle as set forth in claim 1 in which the drive axle is forward of the tag axle.

9 . The truck vehicle as set forth in claim 1 in which the controller comprises a control strategy for controlling the mechanism to apportion a percentage of the sum total of weight borne by the tandem axle to the drive axle to a percentage within a range between a minimum percentage load and a maximum percentage load, a percentage of the sum total of weight borne by the tandem axle to the drive axle to a percentage within a range between the minimum percentage load and the maximum percentage load with the sum of the apportioned percentages always equaling 100%

10 . The truck vehicle as set forth in claim 9 in which the respective percentages apportioned to the drive axle and to the tag axle by the controller are functions of load borne by the drive axle, load borne by the tag axle, and slip of at least one wheel of the drive axle.

11 . The truck vehicle as set forth in claim 9 in which the control strategy operates the mechanism to control the respective percentages apportioned to the drive axle and to the tag axle as a function of a load control range for load borne by one of the axles of the tandem axle and as a function of a drive axle wheel slip control range for at least one wheel of the drive axle.

12 . The truck vehicle as set forth in claim 11 in which the control strategy operates the mechanism to cause the percentage apportioned to the drive axle to increase and the percentage apportioned to the tag axle to decrease when load borne by the drive axle is less than an upper limit of a load control range for load borne by the drive axle and wheel slip is greater than an upper limit of the drive axle wheel slip control range and to cause the percentage apportioned to the drive axle to decrease and the percentage apportioned to the tag axle to increase when load borne by the tag axle is less than an upper limit of load control range for load borne by the tag axle and wheel slip is less than a lower limit of the drive axle wheel slip control range.

13 . A truck vehicle comprising:
a chassis comprising a chassis frame; steerable right and left front wheels suspended from the chassis frame; a tandem axle comprising a drive axle and a tag axle suspended from the chassis frame rearward of the front wheels; a mechanism for apportioning the sum total of weight borne by the tandem axle between the drive axle and the tag axle; and a controller for controlling the mechanism as a function of at least one variable parameter related to vehicle operation to cause a percentage of the sum total of weight borne by the tandem axle to be apportioned to the drive axle within a range between a minimum percentage load and a maximum percentage load, a percentage of the sum total of weight borne by the tandem axle to the tag axle to be apportioned within a range between the minimum percentage load and the maximum percentage load with the sum of the apportioned percentages always equaling 100%.

14 . The truck vehicle as set forth in claim 13 in which the respective percentages caused to be apportioned to the drive axle and to the tag axle by the controller are functions of load borne by the drive axle, load borne by the tag axle, and slip of at least one drive wheel of the drive axle.

15 . The truck vehicle as set forth in claim 13 in which the control strategy operates the mechanism to control the respective percentages apportioned to the drive axle and to the tag axle to maintain load borne by one of the axles of the tandem axle within an axle load control range and to maintain drive axle wheel slip within a drive axle wheel slip control range for at least one drive wheel of the drive axle.

16 . The truck vehicle as set forth in claim 15 in which the control strategy operates the mechanism to cause the percentage apportioned to the drive axle to increase and the percentage apportioned to the tag axle to decrease when load borne by the drive axle is less than an upper limit of a drive axle load control range for load borne by the drive axle and wheel slip of at least one wheel of the drive axle is greater than an upper limit of the drive axle wheel slip control range and to cause the percentage apportioned to the drive axle to decrease and the percentage apportioned to the tag axle to increase when load borne by the tag axle is less than an upper limit of a tag axle load control range for load borne by the tag axle and wheel slip of at least one wheel of the drive axle is less than a lower limit of the drive axle wheel slip control range.

17 . A method for controlling a mechanism to apportion the sum total of weight borne by a tandem axle of a vehicle between a drive axle and a tag axle of the

Assignees

• Int Truck Ip Co Llc

Inventors

• Siuchta Grzegorz
• Korson James Jerome

Classifications

• B62D61/125

  the retractable wheel being a part of a set of tandem wheels (resilient suspension for a single set of tandem wheels B60G5/00) · CPC title

• B62D61/12

  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

• B60W40/13

  Load or weight · CPC title

• B62D53/068 Primary

  having devices to equalise or modify the load between the fifth wheel and the rear wheels (adjustable couping saddles per se B62D53/0807; load transfer devices to permit coupling or uncoupling B62D53/0857; anti jack-knifing devices B62D53/0871) · CPC title

• B60W2040/1307

  Load distribution on each wheel suspension · CPC title