Railway truck assembly having compressible side bearings
A side bearing assembly for a truck assembly of a rail vehicle includes a base, a cap moveably coupled to the base, and one or more elastomer springs disposed between the base and the cap. The one or more elastomer springs include a foam having air pockets that are configured be compressed.
1. A side bearing assembly for a truck assembly of a rail vehicle, the side bearing assembly comprising:
a base comprising an internal chamber;
a cap moveably coupled to the base, wherein the cap comprises a perimeter wall extending from a top surface, and wherein a retaining chamber is defined between the top surface and the perimeter wall; and
one or more elastomer springs disposed between the base and the cap, wherein the one or more elastomer springs comprise at least a portion contained within the retaining chamber between the top surface and the perimeter wall, and
wherein the one or more elastomer springs comprise:
a foam having air pockets that are configured to be compressed;
a head having a first width, wherein the at least a portion contained within the retaining chamber includes the head; and
a neck having a second width that is less than the first width, wherein the neck is within the internal chamber and outside of the cap, and wherein an intermediate width between the first width and the second width gradually and constantly decreases from the first width to the second width.
2. The side bearing assembly of claim 1 , wherein the air pockets form at least half of the one or more elastomer springs.
3. The side bearing assembly of claim 1 , wherein the one or more elastomer springs further comprise a foot having a third width that is greater than the second width.
4. The side bearing assembly of claim 1 , wherein the base comprises a central stand, and wherein the elastomer spring is contained between the cap and the central stand.
5. The side bearing assembly of claim 1 , wherein the base comprises a collar having an alignment rim, and wherein the alignment rim extends inwardly toward the cap.
6. The side bearing assembly of claim 1 , further comprising one or more friction modifiers disposed between a collar of the base and a wall of the cap.
7. The side bearing assembly of claim 1 , wherein the cap comprises a lower ledge, and wherein the base comprises a collar having an upper ridge, wherein the cap is below the upper ridge.
8. The side bearing assembly of claim 1 , wherein the one or more elastomer springs comprise a first elastomer spring and a second elastomer spring.
9. The side bearing assembly of claim 8 , wherein the first elastomer spring has a first density, and wherein the second elastomer spring has a second density that differs from the first density.
10. The side bearing assembly of claim 1 , wherein the one or more elastomer springs comprise one or more indentations.
11. The side bearing assembly of claim 1 , further comprising an alignment plate that secures the one or more elastomer springs to the base.
12. A method of forming a side bearing assembly for a truck assembly of a rail vehicle, the method comprising:
moveably coupling a cap to a base, wherein the cap comprises a perimeter wall extending from a top surface, wherein a retaining chamber is defined between the top surface and the perimeter wall, and wherein the base comprises an internal chamber; and
disposing one or more elastomer springs between the base and the cap, at least a portion of the one or more elastomer springs being contained within the retaining chamber between the top surface and the perimeter wall,
wherein the one or more elastomer springs comprise:
a foam having air pockets that are configured to be compressed;
a head having a first width, wherein the at least a portion contained within the retaining chamber includes the head; and
a neck having a second width that is less than the first width, wherein the neck is within the internal chamber and outside of the cap, and wherein an intermediate width between the first width and the second width gradually and constantly decreases from the first width to the second width.
13. The method of claim 12 , further comprising forming at least half of the one or more elastomer springs with the air pockets.
14. A truck assembly that is configured to travel along a track having rails, the truck assembly comprising:
a first side frame;
a second side frame;
a bolster extending between the first side frame and the second side frame;
a first wheel set coupled to the first side frame and the second side frame;
a second wheel set coupled to the first side frame and the second side frame;
a first side bearing assembly coupled to the bolster; and
a second side bearing assembly coupled to the bolster, wherein the first side bearing assembly is mounted on a top surface of the bolster between a bolster center bowl and a first end, and wherein the second side bearing assembly is mounted on the top surface of the bolster between the bolster center bowl and a second end, wherein each of the first side bearing assembly and the second side bearing assembly comprises:
a base comprising an internal chamber;
a cap moveably coupled to the base, wherein the cap comprises a perimeter wall extending from a top surface, and wherein a retaining chamber is defined between the top surface and the perimeter wall; and
one or more elastomer springs disposed between the base and the cap, wherein the one or more elastomer springs comprise at least a portion contained within the retaining chamber between the top surface and the perimeter wall, and
wherein the one or more elastomer springs comprise:
a foam having air pockets that are configured to be compressed;
a head having a first width, wherein the at least a portion contained within the retaining chamber includes the head; and
a neck having a second width that is less than the first width, wherein the neck is within the internal chamber and outside of the cap, and wherein an intermediate width between the first width and the second width gradually and constantly decreases from the first width to the second width.
15. The truck assembly of claim 14 , wherein the air pockets form at least half of the one or more elastomer springs.
16. The truck assembly of claim 14 , wherein the base comprises a collar having an alignment rim, and wherein the alignment rim extends inwardly toward the cap.
17. The truck assembly of claim 14 , wherein the each of the first side bearing assembly and the second side bearing assembly further comprises one or more friction modifiers disposed between a collar of the base and a wall of the cap.
18. The truck assembly of claim 14 , wherein the cap comprises a lower ledge, and wherein the base comprises a collar having an upper ridge, wherein the cap is below the upper ridge.
19. The truck assembly of claim 14 , wherein the one or more elastomer springs comprise a first elastomer spring and a second elastomer spring, wherein the first elastomer spring has a first density, and wherein the second elastomer spring has a second density that differs from the first density.
20. The truck assembly of claim 14 , wherein the one or more elastomer springs comprise one or more indentations.
21. The truck assembly of claim 14 , wherein the one or more elastomer springs further comprise a foot having a third width that is greater than the second width.