Eduard Locher (15 January 1840 in Zurich – 2 June 1910 in Zurich) was a

Swiss Swiss may refer to: * the adjectival form of Switzerland * Swiss people Places * Swiss, Missouri * Swiss, North Carolina *Swiss, West Virginia * Swiss, Wisconsin Other uses *Swiss-system tournament, in various games and sports *Swiss Internation ...

engineer, inventor and independent

contractor A contractor is a person or company that performs work on a contract basis. The term may refer to: Business roles * Defense contractor, arms industry which provides weapons or military goods to a government * General contractor, an individual o ...

who received a doctorate ''honoris causa'' for his work. He devised the Locher rack railway system and built his privately owned

Pilatus Railway The Pilatus Railway (german: Pilatusbahn, links=no, PB) is a mountain railway in Switzerland and the steepest rack railway in the world, with a maximum gradient of 48% and an average gradient of 35%. The line runs from Alpnachstad, on Lake Alpna ...

that uses this system. Pilatus2

The Locher rack system invented by Eduard Locher, has

gear A gear is a rotating circular machine part having cut teeth or, in the case of a cogwheel or gearwheel, inserted teeth (called ''cogs''), which mesh with another (compatible) toothed part to transmit (convert) torque and speed. The basic pr ...

teeth cut in the sides rather than the top of the rail, engaged by two cog wheels on the locomotive. This system allows use on steeper grades than the other systems, whose teeth could jump out of the rack. It is used on the

. Locher set out to design a rack system that could be used on gradients as steep as 1 in 2 (50%). The Abt system - the most common rack system in

Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...

at the time - was limited to a maximum gradient of 1 in 4 (25%). Locher showed that on steeper grade, the Abt system was prone to the driving pinion over-riding the rack, causing potentially catastrophic derailments, as predicted by Dr. Abt. To overcome this problem and allow a rack line up the steep sides of Mt. Pilatus, Locher developed a rack system where the rack is a flat bar with symmetrical, horizontal teeth. Horizontal pinions engage the centrally-mounted bar, both driving the locomotive and keeping it centered on the track. This system provides very stable attachment to the track, also protecting the car from toppling over even under the most severe crosswinds. Such gears are also capable of leading the car, so even flanges on running wheels are optional. The biggest shortcoming of the system is that the standard

railway switch A railroad switch (), turnout, or ''set ofpoints () is a mechanical installation enabling railway trains to be guided from one track to another, such as at a railway junction or where a spur or siding branches off. The most common typ ...

is not usable, and a

transfer table A transfer table or traverser is a piece of railway equipment. It functions similarly to a turntable, although it cannot be used to turn vehicles around. Overview A transfer table, also known as a traverser, consists of a single length of track th ...

or other complex device must be used where branching of the track is needed. Following tests, the Locher system was deployed on the

, which opened in 1889. No other public railway uses the Locher system, although some European coal mines use a similar system on steeply graded underground lines.

References

Swiss railway mechanical engineers 1840 births 1910 deaths Rack railways {{Switzerland-engineer-stub