Final answer:
The device on the R46 train that keeps the coupler straight on the open ends of the train is called a draft gear. The draft gear is a mechanical linkage mechanism that helps to maintain a smooth and secure connection between the cars. It plays a crucial role in maintaining the safety and stability of the train.
Step-by-step explanation:
The device on the R46 train that keeps the coupler straight on the open ends of the train is called a draft gear.
The draft gear is a mechanical linkage mechanism that helps to absorb and reduce the impact and forces during train coupling and uncoupling, especially when there are speed or weight differences between the cars. It helps to maintain a smooth and secure connection between the cars.
This engineering device plays a crucial role in maintaining the safety and stability of the train as it travels on the tracks.