2。Objects and summary of the invention

Accordingly, it is a primary object of the present invention to provide a new and improved apparatus for allowing a highway vehicle to move along a railroad track。

A further object of the present invention is to provide a new and improved vehicle which can move along highways and along railroad tracks。

A further object of the present invention is to provide an apparatus and a vehicle for rail/highway use which will work satisfactorily with heavy loads such as freight cars。

Yet another object of the present invention is to provide a vehicle, an apparatus, and a method for moving rail cars on light traffic density outlying rail lines。

A further object of the present invention is to provide a vehicle and apparatus for road/rail use which avoids damaging rubber tires when traveling on rails。

Yet another object of the present invention is to provide a vehicle and apparatus for road/rail use which can move relatively quickly on both roads and rails。

3。Rief description of the drawing

These and other objects, features and advantages of the present invention will be more fully disclosed in, or rendered obvious by, the following detailed description of the preferred embodiment of the invention which is to be considered together with the accompanying drawings wherein like numbers refer to like parts and further wherein:

FIG。 1 is a side view of the present invention in a rail mode for traveling along railroad tracks;

FIG。 2 is a side view of the present invention in a road mode (could also be called highway mode) for traveling along a road;

FIG。 3 is a simplified block diagram showing various components of the invention;

FIG。 4 is a side view of an alternative embodiment of the present invention in a road or highway mode for traveling along a road;

FIG。 5 is a side view of the embodiment shown in FIG。4, but in a rail mode for traveling along railroad tracks;

FIG。 6 is a perspective view of the rail drive assembly, including a portion of the flip-up tag axle; and

4。Detailed description of the preferred embodiment

    Turning initially to FIG。 1, a preferred embodiment of the present invention is a road and rail vehicle 10 having a truck tractor vehicle frame 12 with a cab 14 thereon。 A box 16 may house various air equipment used in known fashion for controlling vertically movable axles, air brakes, etc。

A frame extension 18 has been mounted at the front of vehicle 10 for holding a rail wheel guide unit 20 on mount plate 22。 The various wheels and other components discussed herein are symmetric with respect to right and left sides of the vehicle such that the construction of the right side components will be understood from the illustrations and discussions of left side components herein。

The rail guide unit 20 has first and second front left rail engagement wheels 24 which are flanged steel wheels for non-powered engagement with left rail 26 (i。e。, wheels 24 are not driven when the vehicle is in the illustrated rail mode with the rail wheels 24 in a lower, rail position。 The frame extension 18 and rail guide unit 20 may be of a known types used for various previous road vehicles modified to run on rails。 However, unlike various of the common road vehicles modified to run on rails which use road tires for propulsion even in the rail mode, the vehicle 20 is propelled in the rail mode by driving rail engagement wheels。

Driving rail engagement wheels (i。e。, rail engagement wheels which are driven or powered to propel the vehicle) on the vehicle 10 include left back steel flanged rail engagement wheel 28 and left middle (i。e。, middle meaning between the back rail wheel 28 and front rail wheels 24, not necessarily centered) steel non-flanged wheel 30。 Each of the rail wheels 28 and 30 (including the pair on the non-illustrated right side of the vehicle) engages a rail for propelling the vehicle along when in the rail mode。 The left middle rail wheel 30 and similar right wheel are non-flanged such that they do not cause problems when the vehicle 10 goes around a curve。 Although the middle rail wheel 30 is illustrated somewhat offset in the rail direction from back rail wheel 28, the middle wheel 30 might alternately be just in front of wheel 28。