Patent Application
20070089637
An apparatus and method for inter-modal conversion of transport vehicles; rail-to-highway and highway-to-rail.
Not Applicable
Not Applicable
This invention relates generally to the field of vehicle rail adapters and more specifically to an apparatus and method for intermodal conversion of transport vehicles; rail-to-highway and highway-to-rail. Rail modes have proven to be the most efficient means of freight transport because friction losses are minimal, grades are usually 3% or less, and transport is commonly uninterrupted on two way rail lines. However, rail transport in the U.S. is declining because it relies on a cumbersome infrastructure of depots or marshalling yards which impose lost time in train makeup, and cost and time penalties for materials handling.
Highway freight transport has increasingly supplanted the rail mode, offering inherent flexibility of roads and highways which directly link points of origin and destination. This flexibility is especially important for “just in time inventory”, where goods in inventory are in transit to their destination. Depot transfers and warehousing are minimal. However, highway transport is now seeing drawbacks by virtue of its popularity. Roads are more congested with semi tractor-trailers, accidents are frequent, and fuel demand is driving up costs.
The efficiency of rail transport, combined with the flexibility of highway transport, can be realized by rapid, uncomplicated, and inexpensive conversion of highway vehicles to operate on both rails or roadways.
Technology to directly adapt highway vehicles to rails has realized limited routine use in railway maintenance vehicles. These adapters are rail wheel bogies rigidly attached to the vehicle chassis; extended for rail travel and retracted for highway travel. A variant of this approach uses a suspension link between the vehicle chassis and a rail bogie equipped sub-frame. Some innovations use conventional railtrucks (rail car carriage assemblies) as conversion components. Another technology for rail transport of highway vehicles is the specially designed rail car which carries freight trailers “piggy back”. This method of conversion, highway-to-rail and rail-to-highway, requires a locally fixed mechanized handling infrastructure to on-load and off-load vehicles.
Railtruck based adapters offer a means for conversion, but in so using, ramps or lifts to accommodate mating of vehicles to adapters are required. Rigidly attached highway vehicle rail adapters are limited to short runs at low speed operation because there is no shock absorbing suspension, and they require an added hydraulic system for actuation. A bogie equipped sub-frame variant of this approach provides suspension, but adds significant weight. Further, most adapters do not offer sufficient draft load transfer capabilities necessary for multi-vehicle train configurations.
Dedicated rail cars outfitted for highway freight trailer transfer are an expensive capital investment for single purpose use. Furthermore, this mode of rail transfer requires limited “on-time”, fixed terminal handling facilities to on-load and off-load freight trailers. Both expense and lack of routing flexibility make this option unattractive.
Objects
The primary object of the invention is to provide an economical means to conduct reversible intermodal conversion of vehicles, without fixed mechanical infrastructure or add-on systems, from highway-to-rail from paved rail stages; such conversion affording both rail transport efficiencies and highway routing flexibility. Another object of the invention is to reduce transport fuel consumption by replacing pneumatic tire drag with solid wheels-on-rails and to afford close proximity inter-vehicle drafting to reduce air drag. Another object of the invention is to reduce fuel consumption at by eliminating highway braking, acceleration and periodic stops at engine idle. A further object of the invention is to improve overall delivery time at by avoiding traffic delays. Yet another object of the invention is to reduce accident liability exposure by avoiding highway encounters. Still yet another object of the invention is to enable highway-to-rail and rail-to-highway transition without a mechanized vehicle handling infrastructure or vehicle modifications.
Another object of the invention is to realize the economy of mass transit, yet retain the flexibility to select points of origin and destination. Another object of the invention is to maximize payload by avoiding highway weight restrictions. A further object of the invention is to avoid overland highway use fees by selecting rail transit. Yet another object of the invention is to reduce labor costs by increasing transport payload-to-manpower ratio by at least an order of magnitude. Still yet another object of the invention is to eliminate major cross-country transport vehicle wear, theft, and damage vulnerability.
Other objects and advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.
In accordance with a preferred embodiment of the invention, there is disclosed an apparatus for reversible intermodal conversion of highway transport trailers, including those designed for highway transit of maritime containerized cargo, highway-to-rail comprising: a rail car carriage assembly (railtruck) with a top mounted fifth wheel and an underside affixed draft sill; a rail gage solid wheel bogie assembly with cradles for said trailer axles; and a rear axle housing affixed draft sill pin receptacle. The rail car carriage assembly is also fitted with a standard height rail car knuckle coupler. The draft sill, height positioned under vehicle axles, is end fitted with draft and pneumatic couplers and a trailer axle housing receptacle mating pin. The rail car carriage assembly, draft sill with attachments, and rail compatible bogie assembly comprise the trailer rail interface apparatus for conversion of highway freight trailers to rail transport mode.
In accordance with a preferred embodiment of the invention, there is disclosed an inter-modal transition method for trailers from highway-to-rail using said apparatus for trailers as follows: A highway trailer with wheel outboard displacement shims and rear axle housing centerline pin receptacle is aligned coaxially with rail tracks on a slightly elevated stage by a highway tractor. The trailer is front-end jacked with the standard (intrinsic) trailer front dolly. The highway tractor is driven off the staging area and the rail interface apparatus is backed under the trailer by a rail motive power vehicle, or equivalent. Attachment is complete when the fifth wheel draft pin is secured and the rear axle pin and receptacle are engaged. The rail adapted trailer is next positioned off the staging area to bear axles on bogie cradles for rail operation. Reverse of the procedure delineated above is executed for transition from rail-to-highway mode of transit.
In accordance with a preferred embodiment of the invention, there is disclosed an apparatus for reversible intermodal conversion of highway transport tractors, highway-to-rail comprising: fore and aft rail compatible solid wheel bogies with tractor axle cradles; and a bogie interconnecting articulated draft sill, linked by pin and clevis. The articulated draft sill, height positioned under vehicle axles, is end fitted with draft and pneumatic couplers. The two bogies and articulated draft sill with attachments comprise the tractor rail interface apparatus for conversion of highway tractors to rail transport mode. Further, the tractor fore bogie with a draft sill adapter functions as a trailer rail interface apparatus for coupled tractor/trailer operation as a unit. The rail transition method for an adapted tractor/trailer unit is functionally identical to the tractor transition.
In accordance with a preferred embodiment of the invention, there is disclosed an intermodal transition method for tractors from highway-to-rail using said apparatus for tractors as follows: A highway tractor is positioned coaxially with rails on a slightly elevated stage. The aft bogie is positioned to mate with the tractor fifth wheel by a rail motive power vehicle, or equivalent. Next, the forward bogie is positioned to mate with the aft bogie by a rail motive power vehicle, or equivalent. The draft sills of the fore and aft bogies are linked with a linch pin at the clevis hinge point. The tractor is driven off-pavement, on-tracks with all pneumatic tire wheels elevated by axle cradles for un-powered rail transit. Alternatively, the aft bogie axle cradles may be lowered for tractor drive wheel rail contact in a rail draft operation. Reverse of the procedure delineated above is executed for transition from rail-to-highway mode of transit.
The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
Detailed descriptions of the preferred embodiment are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.
In the illustrated and described embodiment of this invention, both apparatus and method for vehicle intermodal transition, highway-to-rail and rail-to-highway, are presented. The purpose of the invention is to afford the flexibility of selecting highways leading from origin and to destination, while providing the economy of rail operation for overland expanses of the route. This is accomplished by staging inter-modal transition at rail grade crossings or paved rail spurs without need for a fixed mechanized infrastructure, or powered actuators.
The apparatus for intermodal rail transition consists of attaching highway vehicles to a rail interface apparatus. The rail interface apparatus for trailers, shown in
The method of highway trailer transition to rail involves staging the trailer on pavement slightly elevated above rail caps, securing the rail interface apparatus under the trailer, and translating the mated unit off-the-stage to rail level to bear trailer loads on the interface apparatus. The method of highway tractor transition involves similar staging over a two bogie rail interface apparatus on pavement slightly above track cap elevation. Tractor translation off-pavement is conducted to bear loads on cradles, with drive wheel tires placed on tracks for traction applications and cradle vertical adjustment to clear tracks for un-powered transit. An adapter configuration option accommodates rail transition of a coupled tractor/trailer unit. Reversal of the above trailer and tractor transition methods returns vehicles to highway use.
While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
