Railroad Truck Providing Improved Dynamic Characteristics Of The Freight Railway Car And The Railroad Truck Components

Abstract

An novel railway car truck comprising side frames with vertical columns and bolster openings, a central swing suspension, a bolster, side bearers, and friction shock absorber friction wedges that has an improved dynamic performance facilitated by a novel central swing suspension set of springs and/or a novel design of the friction shock absorber friction wedges and/or a novel design of the side bearings.

What is claimed is: 
     
         1 . A railway truck comprising:
 a first sideframe and a second sideframe distanced from the first sideframe, the sideframes including:
 an opening including a vertical column and a bearing surface; 
 a spring assembly disposed on the bearing surface; 
   a bolster having two mating sections at opposite ends, wherein each of the mating sections includes a sloped pocket, wherein one of the mating sections is disposed within the opening of the first sideframe and the other mating section is disposed within the opening of the second sideframe;   a first sideframe friction wedge disposed within the opening of the first sideframe and a second sideframe friction wedge disposed within the opening of the second sideframe, the friction wedges including:
 a sloped side engageable with the sloped pocket of the bolster mating section; 
 a vertical side engageable with vertical column of the bolster opening; 
 a side supportable by the spring assembly; 
   wherein the friction coefficient of the engagement between the vertical side of the wedge and the vertical column is two to three times greater than the friction coefficient of the engagement between the sloped side of the wedge and the sloped pocket.   
     
     
         2 . The railway truck of  claim 1  wherein the sloped side of the friction wedges comprises at least two front bearing surfaces that are at an angle between 130 degrees and 150 degrees to each other. 
     
     
         3 . The railway truck of  claim 1  wherein the sloped side of the friction wedges is at an angle between 50 degrees and 65 degrees to the side supportable by the spring assembly of the friction wedges. 
     
     
         4 . The railway truck of  claim 1  wherein the sloped side of the friction wedges comprises two front bearing surfaces that are at an angle to one another and are arc shaped. 
     
     
         5 . The railway truck of  claim 1  wherein each vertical column comprises a friction pad and the friction pad has a surface roughness between Rz 40 and Rz 80. 
     
     
         6 . The railway truck of  claim 1  wherein each vertical column comprises a friction pad and the friction pad has a vertical height between 245 millimeters and 260 millimeters and wherein the pocket comprises an insert that interfaces with the wedge. 
     
     
         7 . The railway truck of  claim 1  wherein the sloped side of the friction wedges comprises two front bearing surfaces that are at an angle to one another and an intermediate front section between the two front bearing surfaces, the intermediate front section having a convex surface with a radius between 650 millimeters and 920 millimeters in the plane between the two front bearing surfaces. 
     
     
         8 . The railway truck of  claim 1  wherein the sloped side of the friction wedges comprises two front bearing surfaces that are at an angle to one another and an intermediate front section between the two front bearing surfaces, the intermediate front section defining a recess. 
     
     
         9 . A railway truck comprising:
 a first sideframe and a second sideframe distanced from the first sideframe, the sideframes including:
 an opening including a vertical column and a bearing surface; 
 a spring assembly with a deflection safety factor between 1.5 and 1.75 disposed on the bearing surface; 
   a bolster having two mating sections at opposite ends, wherein each of the mating sections includes a sloped pocket, wherein one of the mating sections is disposed within the opening of the first sideframe and the other mating section is disposed within the opening of the second sideframe;   a first sideframe friction wedge disposed within the opening of the first sideframe and a second sideframe friction wedge disposed within the opening of the second sideframe.   
     
     
         10 . The railway truck of  claim 9 , wherein each spring assembly comprises at least one wedge spring configured to support the corresponding friction wedge, wherein the at least one wedge spring includes an outer spring and an inner spring; and
 wherein the uncompressed height of the wedge spring outer spring is between 6 millimeters and 10 millimeters less than an uncompressed height of the wedge spring inner spring.   
     
     
         11 . The railway truck of  claim 9 , wherein each spring assembly comprises at least one wedge spring configured to support the corresponding friction wedge and the wedge spring has a total stiffness of 353.7 KN/m. 
     
     
         12 . The railway truck of  claim 9 , wherein each spring assembly comprises at least one wedge spring configured to support the corresponding friction wedge and at least one bolster spring configured to support the corresponding bolster mating section,
 wherein the ratio of an uncompressed height of the bolster spring to an uncompressed height of the wedge spring is between 0.9 and 0.95.   
     
     
         13 . The railway truck of  claim 9 , wherein the first and second friction wedges include:
 a sloped side engageable with the sloped pocket of the bolster mating section;   a vertical side engageable with vertical column of the bolster opening;   a side supportable by the spring assembly;   wherein the friction coefficient of the engagement between the vertical side of the wedge and the vertical column is two to three times greater than the friction coefficient of the engagement between the sloped side of the wedge and the sloped pocket.   
     
     
         14 . A railway truck comprising:
 a first sideframe and a second sideframe distanced from the first sideframe, the sideframes including:
 an opening; 
   a bolster having two mating sections at opposite ends, wherein each of the mating sections includes a sloped pocket, wherein one of the mating sections is disposed within the opening of the first sideframe and the other mating section is disposed within the opening of the second sideframe;   a side bearer disposed on the bolster, the side bearer including:
 a carrier body; 
 a springing element disposed within the carrier body; 
 a stop sleeve slidably engaged with the carrier body, the stop sleeve surrounding and supported by the springing element, and; 
 wherein the springing element has a dynamic deflection safety of 16.6 millimeters. 
   
     
     
         15 . The railway truck of  claim 14 , wherein the springing element includes a plurality of concentric springs with springs with larger diameters having higher stiffness than springs with smaller diameters. 
     
     
         16 . The railway truck of  claim 14 , wherein the springing element has a vertical stiffness between 564 kN/m and 1073 kN/m. 
     
     
         17 . The railway truck of  claim 14 , further comprising a support plate disposed between the springing element and the sleeve. 
     
     
         18 . The railway truck of  claim 14 , wherein the opening of the first sideframe and opening of the second sideframe each further includes:
 a vertical column and a bearing surface;   a spring assembly disposed on the bearing surface;   wherein the truck further comprises a first sideframe friction wedge disposed within the opening of the first sideframe and a second sideframe friction wedge disposed within the opening of the second sideframe, the friction wedges comprising:
 a sloped side frictionally engageable with the sloped pocket of the bolster mating section; 
 a vertical side frictionally engageable with vertical column of the bolster opening; 
 a side supportable by the spring assembly; 
 wherein the friction coefficient of the engagement between the vertical side of the wedge and the vertical column is two to three times greater than the friction coefficient of the engagement between the sloped side of the wedge and the sloped pocket. 
   
     
     
         19 . The railway truck of  claim 18 , wherein the vertical side of each friction wedge has a vertical height between 135 millimeters and 160 millimeters, and the vertical side of each friction wedge has a width between 155 millimeters and 175 millimeters.