Filing Information

Inventor(s)	Earl D. Smith ·
Assignee(s)	DBX Engineering Corp. ·  View assignee updates
Attorney/Agent(s)	Woodard, Emhardt, Naughton, Moriarity & McNett ·
Primary Examiner	Margaret A. Focarino ·
Assistant Examiner	F. Zeender ·
Application Number	US8192139
Filing date	02/04/1994
Issue date	04/09/1996
Predicted expiration date	02/04/2014
U.S. Classifications	180/246  · 180/371  ·
International Classifications	B60K 17354  ·
Kind Code	A
International Classifications	180233;245;246;248;337;371;376;24.08;24.11;22;379;383;385;711;713;698;234 ·

Patent Family

Abstract

A four wheel drive and steering system for a motor vehicle includes a splitter gear assembly coupled to the transmission for splitting rotational power between the front wheels and one set of wheels of a tandem rear wheel vehicle. A first drive train rotationally couples the front wheels to the transmission, while a second drive train drives the one set of rear wheels. The second drive train includes a pair of shaft assemblies, each corresponding to a respective rear wheel. Each of the pair of shaft assemblies includes a rear shaft extending substantially parallel to the longitudinal axis of the vehicle adjacent a vertical plane including the corresponding rear wheels, thereby providing clearance for the floor of a dropframe cargo compartment. A transfer gear assembly couples the corresponding rear wheel to the rear shaft of the shaft assembly. The steering system is coupled between the steering linkage for the front wheels and the other set of tandem rear wheels. The steering system includes an actuator connected to the front steering linkage that provides a hydraulic signal to a power cylinder between the rear wheels. A rear wheel linkage connects the power cylinder to the rear wheels to turn the rear wheels in proportion to the degree of turn of the front wheels.

Independent Claims | See all claims (13)

1. 1. A four wheel drive system for a motor vehicle having a frame with a longitudinal axis, an engine, a transmission operatively coupled to the engine, a pair of ground engaging steerable front wheels and a pair of ground engaging rear wheels having a first rear wheel and a second rear wheel, the system comprising:means for splitting rotational power from the transmission between the front wheels and the rear wheels;a first drive train rotationally coupled between said means for splitting and the front wheels for driving the front wheels; anda second drive train rotationally coupled between said means for splitting and the rear wheels for driving the rear wheels, and including:a first shaft assembly rotationally connected to said means for splitting and including a first rear shaft extending substantially parallel to the longitudinal axis of the vehicle adjacent a first vertical plane including said first rear wheel;a second shaft assembly rotationally connected to said means for splitting and including a second rear shaft extending substantially parallel to the longitudinal axis of the vehicle adjacent a second vertical plane including said second rear wheel;a first transfer gear assembly connected between said first rear wheel and said first rear shaft; anda second transfer gear assembly connected between said second rear wheel and said second rear shaft.
2. 11. A drive system for a motor vehicle having an engine, a transmission operatively coupled to the engine, a pair of ground engaging steerable front wheels and a pair of ground engaging rear wheels having a first rear wheel and a second rear wheel, the system comprising:means for splitting rotational power from the transmission between the front wheels and the rear wheels;a first shaft assembly including;a first transverse shaft connected to the transmission and extending transverse to the longitudinal axis of the vehicle;a first rear shaft extending parallel to the longitudinal axis of the vehicle adjacent a first vertical plane including said first rear wheel;a first transfer gear assembly connected between said first transverse shaft and said first rear shaft;a second transverse shaft connected to the transmission and extending transverse to the longitudinal axis of the vehicle;a second rear shaft extending parallel to the longitudinal axis of the vehicle adjacent a second vertical plane including said second rear wheel;a second transfer gear assembly connected between said second transverse shaft and said second rear shaft;a third transfer gear assembly connected between said first rear wheel and said first rear shaft to provide drive power to said first rear wheel; anda fourth transfer gear assembly connected between said second rear wheel and said second rear shaft to provide drive power to said second rear wheel.