Funicular

A funicular (/fᵿˈnɪkjᵿlər/), also known as an inclined plane or cliff railway, is a cable railway in which a cable attached to a pair of tram-like vehicles on rails moves them up and down a steep slope, the ascending and descending vehicles counterbalancing each other. Funiculars of one sort or another have existed for hundreds of years and continue to be used for moving both passengers and goods. Its name derives from the latin, funiculus, diminutive of funis, meaning "rope".

The basic idea of funicular operation is that two cars are always attached to each other by a cable, which runs through a pulley at the top of the slope. Counterbalancing of the two cars, with one going up and one going down, minimizes the energy needed to lift the car going up. Winching is normally done by an electric drive that turns the pulley. Sheave wheels guide the cable to and from the drive mechanism and the slope cars.

Early funiculars used two parallel straight tracks, four rails, with separate station platforms for each vehicle. The tracks are laid with sufficient space between them for the two cars to pass at the midpoint. The wheels of the cars are usually single-flanged, as on standard railway vehicles. Examples of this type of track layout are the Duquesne Incline in Pittsburgh, Pennsylvania, and most cliff railways in the UK.

Layouts that require less width have been developed, with only two or three rails for the most part of the slope and four rails only at the passing section.

The Swiss engineer Carl Roman Abt invented the method that allows cars to be used with a two-rail configuration: the outboard wheels have flanges on both sides, which keeps them aligned with the outer rail, thus holding each car in position, whereas the inboard wheels are unflanged and ride on top of the opposite rail, thereby easily crossing over the rails (and cable) at the passing track.

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