Back to results
US 6,659,016 B2Granted
Rail road freight car with resilient suspension
AssigneeNational Steel Car Limited
InventorJames W. Forbes
Life of this patent
Estimating the term…
Abstract
An auto rack rail road freight car is provided for carrying low density, relatively high value, relatively fragile lading. The car has a relatively soft suspension and an empty vertical bounce natural frequency of less than 2.0 Hz. The car also has additional ballast to increase the dead sprung weight of the car relative to the weight of the lading. In the embodiments in which multi-unit articulated freight cars are employed, such as for auto rack rail cars, the ballast is located preferentially toward the coupler end trucks. The trucks for the railcar have an increased wheel base and damping located to provide a greater moment arm and bearing face to encourage a higher threshold for rail car hunting.
Claims46
A rail road freight car having:
- at least one rail car unit, said rail road freight car being supported by three piece rail car trucks for rolling motion along rail road tracks;
- each of said three piece trucks having a rigid truck bolster and a pair of first and second side frame assemblies, the bolster having first and second ends and the side frames being mounted at either end of the truck bolster;
- said three piece trucks each having a resilient suspension mounted between said truck bolster and said side frames;
- said rail road freight car having a sprung mass;
- a first portion of said sprung mass being carried by a first of said rail car trucks;
- said resilient suspension of said first of said trucks having a first vertical bounce spring rate;
- a first vertical bounce natural frequency of said first truck, being defined as the square root of the value obtained by dividing said first vertical bounce spring rate by said first portion of said sprung mass;
- and
- said first vertical bounce natural frequency being less than 2.0 Hz. when said rail road car is unloaded.
6 more elements
An articulated rail road car carried on three piece trucks for rolling motion along rail road tracks, wherein:
- said rail road car includes at least first and second rail car end units;
- each said end unit having a first end having a releasable coupler mounted thereto, and a second end connected by an articulated connection to an adjacent rail car unit;
- said first end unit has a first of said three piece trucks mounted thereunder closer to said first end of said first end unit than to said second end of said first end unit;
- and
- said first end unit having a dead sprung weight, and a weight distribution of said dead sprung weight, said weight distribution being biased toward said coupler end thereof.
2 more elements
An articulated rail road freight car comprising:
- at least a first rail car unit and a second rail car unit joined at an articulated connection;
- said articulated rail road car being carried by rail car trucks for rolling motion along rail road tracks;
- two of said rail car units being end units;
- said first rail car unit being one of said end units;
- said first end unit having a first end and a second end;
- said first end of said first rail car unit having a releasable coupler mounted thereto and said second end being joined by said articulated connection to said second rail car unit;
- a first of said trucks being mounted to said first rail car unit at a first truck center, said first truck center lying closer to said first end of said first rail car unit than to said second end;
- a second of said trucks being mounted closer to said articulation between said first and second rail car units than any other of said trucks;
- said first car unit having a weight and a dead load weight distribution;
- and
- said dead load weight distribution of said first rail car unit being biased toward said first end of said first rail car unit.
8 more elements
An articulated rail road freight car comprising:
- a number of rail car units connected at a number of articulated connectors, said rail car units being supported for rolling direction along rail road tracks by a number of rail car trucks;
- the number of articulated connectors being one less than the number of railcar units, each articulated connector being located between two adjacent ones of said rail car units;
- the number of rail car trucks being one greater than the number of rail car units;
- said rail car units each have a dead sprung weight, said dead sprung weights of said rail cars being distributed among said trucks;
- an average dead sprung weight per truck, W0, being equal to the total dead sprung weight of all of said rail car units divided by the total number of said trucks;
- each of said rail car truck bears a dead sprung weight, WDS;
- and
- for each of said trucks WDS lies in the range of ⅔ to {fraction (4/3)} of W0.
5 more elements
A rail road freight car having:
- at least one rail car unit, said rail road freight car being supported by three piece rail car trucks for rolling motion along rail road tracks;
- each of said three piece trucks having a rigid truck bolster and a pair of first and second side frame assemblies, the bolster having first and second ends and the side frames being mounted at either end of the truck bolster;
- said three piece trucks each having a resilient suspension mounted between said truck bolster and said side frames;
- said rail road freight car having a sprung mass;
- a first portion of said sprung mass being carried by a first of said rail car trucks;
- said resilient suspension of said first of said trucks having a first vertical bounce spring rate;
- a vertical bounce natural frequency of said first truck, being defined as being the square root of the value obtained by dividing said first vertical bounce spring rate by said first portion of said sprung mass;
- said first vertical bounce natural frequency being less than 4.0 Hz. when said rail road car is unloaded;
- and
- said first three piece truck has a wheelbase of greater than 80 inches.
7 more elements
Dependencies are inferred from the claim text.