Drive axle system having a clutching device

Patent metadata

Field	Value
Publication number	US-9428050-B2
Application number	US-201514790292-A
Country	US
Kind code	B2
Filing date	Jul 2, 2015
Priority date	Jul 20, 2010
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

A method of operating a drive axle system is provided. The method comprises the steps of rotating a first shaft, drivingly engaging a first axle assembly, drivingly engaging a second axle assembly, moving a second clutching device into a position to disengage a second driving gear of the second axle assembly, and moving a first clutching device into a position to disengage a first portion from a second portion of one of a second pair of output axles, thereby allowing the second driving gear to coast to a substantially non-moving state.

First claim

What is claimed is:

1. A method of operating a drive axle system, the method comprising the steps of:
rotating a first shaft, the first shaft comprising at least one shaft section;
drivingly engaging a first axle assembly, the first axle assembly comprising a first wheel differential, a first driving gear coupled to the first wheel differential which the first shaft is drivingly engaged with, and a first pair of output axles drivingly engaged with the first wheel differential, wherein the first axle assembly further comprises an axle ratio selection device comprising a planetary gear set;
drivingly engaging a second axle assembly comprising a second wheel differential, a second driving gear coupled to the second wheel differential, a second pair of output axles drivingly engaged with the second wheel differential, and a first clutching device disposed on and dividing one of the second pair of output axles into first and second portions, the second driving gear drivingly engaged with one of the first shaft and the first driving gear through a second clutching device;
moving the second clutching device into a position to disengage the second driving gear from one of the first shaft and the first driving gear; and
moving the first clutching device into a position to disengage the first portion from the second portion of one of the second pair of output axles, thereby allowing the second driving gear to coast to a substantially non-moving state.

2. The method of operating a drive axle system according to claim 1 , wherein the first axle assembly has at least two first axle ratios and the second axle assembly has a second axle ratio, one of the at least two first axle ratios different from the second axle ratio.

3. The method of operating a drive axle system according to claim 1 , further comprising the step of providing a bevel gear inter-axle differential, the bevel gear inter-axle differential for distributing a torque applied to the first shaft to the first driving gear and the second driving gear, the bevel gear inter-axle differential in a locked up position and forming a portion of the first shaft when the second clutching device is in the position disengaging the second driving gear from the first shaft.

4. The method of operating a drive axle system according to claim 1 , further comprising the step of providing a planetary inter-axle differential, the planetary inter-axle differential for distributing a torque applied to the first shaft to the first driving gear and the second driving gear, the planetary inter-axle differential in a locked up position and forming a portion of the first shaft when the second clutching device is in the position disengaging the second driving gear from the first shaft.

5. The method of operating a drive axle system according to claim 1 , further comprising the step of providing an output gear and an inter-axle shaft drivingly engaged with the second driving gear and wherein the second clutching device is a plate clutch concentrically disposed about the first shaft capable of engaging the output gear with the first shaft, the plate clutch allowing the second driving gear, the output gear, and the inter-axle shaft to coast to a non-moving state when the plate clutch is in a position disengaging the second driving gear from the first shaft.

6. The method of operating a drive axle system according to claim 1 , further comprising the step of providing an output gear and an inter-axle shaft drivingly engaged with the second driving gear and wherein the second clutching device is a synchronizer concentrically disposed about the first shaft capable of engaging the output gear with the first shaft, the synchronizer allowing the second driving gear, the output gear, and the inter-axle shaft to coast to a non-moving state when the synchronizer is in a position disengaging the second driving gear from the first shaft.

7. A method of utilizing a drive axle system, the method comprising the steps of:
rotating a first shaft, the first shaft comprising at least one shaft section;
providing a bevel gear inter-axle differential comprising a first side gear, a driving spider, and a second side gear, the driving spider drivingly engaged with the first shaft;
drivingly engaging a first axle assembly, the first axle assembly comprising a first wheel differential, a first driving gear coupled to the first wheel differential which the second side gear of the bevel gear inter-axle differential is drivingly engaged with, and a first pair of output axles drivingly engaged with the first wheel differential;
drivingly engaging a second axle assembly, the second axle assembly comprising a second wheel differential, a second driving gear coupled to the second wheel differential, a second pair of output axles drivingly engaged with the second wheel differential, and a first clutching device disposed on and dividing one of the second pair of output axles into first and second portions, the second driving gear drivingly engaged with one of the first shaft and the first driving gear through a second clutching device;
moving the second clutching device into a position to drivingly engage the second driving gear with the first side gear of the bevel gear inter-axle;
moving the first clutching device into a position to drivingly engage the first portion with the second portion of one of the second pair of output axles;
applying a torque to the driving spider through the first shaft;
distributing a first portion of the torque to the first driving gear through the second side gear of the bevel gear inter-axle differential; and
distributing a second portion of the torque to the second driving gear through the first side gear of the bevel gear inter-axle differential.

8. The method of operating a drive axle system according to claim 7 , wherein the second clutching device comprises a shift collar concentrically disposed about the first shaft, the shift collar engaging an output gear and an inter-axle shaft with the second driving gear of the second axle assembly when the second clutching device drivingly engages the second driving gear with the first side gear of the bevel gear inter-axle differential.

9. The method of operating a drive axle system according to claim 7 , wherein the second clutching device comprises a shift collar concentrically disposed about the first shaft and a synchronizer, the synchronizer variably engaging an output gear and an inter-axle shaft with the second driving gear of the second axle assembly prior to the second clutching device drivingly engaging the second driving gear with the first side gear of the bevel gear inter-axle differential.

10. The method of operating a drive axle system according to claim 7 , wherein the first clutching device comprises a second shift collar concentrically disposed about one of the second pair of output axles, the second shift collar drivingly engaging the first portion with the second portion of one of the second pair of output axles when the first clutching device drivingly engages the first portion with the second portion of one of the second pair of output axles.

11. The method of operating a drive axle system according to claim 7 , wherein the first axle assembly further comprises an axle ratio selection device.

12. The method of operating a drive axle system according to claim 11 , wherein the axle ratio selection device comprises a planetary gear set.

13. A method of operating a drive axle system, the method comprising the steps of:
rotating a first shaft, the first shaft comprising at least one shaft section;
providing a planetary inter-axle differential comprising a sun gear, a carrier, and

Assignees

• Dana Heavy Vehicle Sys Group

Inventors

• Ziech James F
• Remboski Donald J
• Wesolowski Steven J
• Morscheck Timothy J

Classifications

• B60Y2400/80

  Differentials · CPC title

• B60Y2300/429

  Control of secondary clutches in drivelines · CPC title

• B60Y2400/424

  Friction clutches · CPC title

• B60K17/16 Primary

  of differential gearing · CPC title

• F16H48/06

  with gears having orbital motion · CPC title