| 摘要 |
A roller assembly for facilitating movement of a switch rail between two positions. In one embodiment, the roller assembly includes a frame adapted for attachment to the switch rail and having a pocket formed therein, and an elastomer assembly, at least a portion of which is slidably disposed within the pocket. The elastomer assembly includes a roller wheel and an elastomeric block. The roller wheel travels along the surface of a tie plate when the switch rail is moved between positions. The elastomeric block is adapted to compress under a load applied to the switch rail in the direction of the tie plate, causing the roller wheel to retract in the direction of the pocket. When the weight of a train is exerted on the roller assembly, the compression of the elastomeric block causes the train to ride fully on the rails, just as if the roller assembly were not present. When no weight is exerted on the roller assembly, the roller assembly assists the switch to move freely between positions. |
