Rail road car with cantilevered articulation

Abstract

An articulated rail car has a plurality of rail car units joined together at articulation connections, and carried upon a number of rail car trucks that is equal to the number of rail car units plus one. At least one of the articulated connectors is located at an offset distance from the nearest rail car truck, such that the adjacent rail car has an overhang, or cantilever, between the center of the truck and the pivot center of the articulation. The truck is a two axle, four-wheel freely pivoting truck.

Description

[0001] This application is a continuation of U.S. patent application Ser. No. 10 / 081,120 filed Feb. 22, 2002, now U.S. Pat. No. 7,047,889, which is a continuation of U.S. patent application Ser. No. 09 / 614,815 filed Jul. 12, 2000, now abandoned.FIELD OF THE INVENTION [0002] This invention relates generally to articulated rail road cars. BACKGROUND OF THE INVENTION [0003] The dimensions of rail road cars are constrained by a number of geometric considerations. First, on tangent track (that is, straight track) a rail road car can not be too wide, otherwise it may foul the sides of bridges, tunnels, roadside fittings such as switches or signals, or other cars of the same size passing on an adjacent track. Similarly, rail cars cannot be taller than the minimum regulated heights of the lowest bridges or tunnels on the tracks along which it is to travel. Third, the weight a car can carry is limited by the capacity of the tracks, rails and road bed over which it is to travel. [0004] With r...

AI Technical Summary

Benefits of technology

"The patent describes an articulated rail road car that has multiple rail car units connected at an articulation point. The car can be a three-pack rail car with a first and second rail car unit, or a two-truck middle unit. The articulation point is located between the first and second rail car units, and the trucks are mounted pivotally to the first rail car unit. The car can also have a plurality of deck structures for vehicles to be loaded, and a plurality of rail car trucks to carry the car. The articulation connection is designed to transfer shear loads and can be located longitudinally eccentrically relative to the truck. The car can also have a plurality of articulation connections between the rail car units, and there may be no trucks between the first and second articulation connections. The technical effects of the invention include improved load capacity, flexibility, and better load distribution."

Problems solved by technology

First, on tangent track (that is, straight track) a rail road car can not be too wide, otherwise it may foul the sides of bridges, tunnels, roadside fittings such as switches or signals, or other cars of the same size passing on an adjacent track.

Similarly, rail cars cannot be taller than the minimum regulated heights of the lowest bridges or tunnels on the tracks along which it is to travel.

Third, the weight a car can carry is limited by the capacity of the tracks, rails and road bed over which it is to travel.

When the clearance allowed is too small, the loading personnel may inadvertently damage the finish of the automobiles, giving rise to damage claims.

In each case, it is helpful to lengthen the car to increase lading, but such lengthening is limited by the need to maintain a car body width.

The use of single axle trucks in an articulated freight car may tend to be disadvantageous.

However, as car length increases, fixed orientation single axle trucks face an increasing angle of attack relative to the rails when running through a curve.

Consequently, single axle trucks tend not to be recommended for rail cars having a separation of more than about 39 feet between trucks.

However, the issue of having to reduce the width of the rail road car occurs when the truck centers are already more than 46 ft.

Second, a single axle truck cannot, in general, carry the same load as a double axle truck having comparable wheels.

A draw bar reduces the clearance required between the car units as compared to releasable couplers, but cannot be used to transmit a shear load.

That is, it may not tend to be advantageous to try to pass a vertical shear load through a draw bar.

Thus use of a draw bar rather than an articulated connector generally requires that there be an adjacent truck mounted to each of the rail car units, with the consequent increase in weight, length, maintenance, and expense.

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