Swiss railway clock

Swiss railway clock
	A Swiss railway clock at Zürich HB
Manufacturer	/
Type	Electric clock
Display	Analog
Introduced	1944
Movement	Synchronous motor

The Swiss railway clock was designed in 1944 by Hans Hilfiker, a Swiss engineer and SBB employee, together with , a clock manufacturer, for use by the Swiss Federal Railways as a station clock.^[1] In 1953, Hilfiker added a red second hand in the shape of the baton used by train dispatch staff.^[2], giving the clock its current appearance.

Technology[]

Virtual clock

The clock owes its technology to the particular requirements of operating a railway. First, railway timetables do not list seconds; trains in Switzerland always leave the station on the full minute. Secondly, all the clocks at a railway station have to run synchronously in order to show reliable time for both passengers and railway personnel anywhere on or around the station.^[3]

The station clocks in Switzerland are synchronized by receiving an electrical impulse from a central master clock at each full minute, advancing the minute hand by one minute. The second hand is driven by an electrical motor independent of the master clock. It takes only about 58.5 seconds to circle the face; then the hand pauses briefly at the top of the clock. It starts a new rotation as soon as it receives the next minute impulse from the master clock.^[3] This movement is emulated in some of the licensed timepieces made by Mondaine.

Cultural impact[]

A monumental clock in Aarau railway station

Since the introduction of the distinctive red second hand in 1953, the clock has become a Swiss national icon.^[4]^[3]^[5] It is included among examples of outstanding 20th-century design by both the Design Museum in London and the Museum of Modern Art in New York City.

The clockface design is notably used in a line of Mondaine watches since 1986.

The clockface design is also licensed for use on certain Apple devices such as iPads and iPhones.^[2] Apple initially used the clock design without permission in iOS 6.^[6]^[7] Although the exact details of the licensing agreement are confidential,^[8] it was reported that Apple ultimately paid Swiss national rail operator SBB about CHF 20M (about US$22.4M as of January 2014) to license the use of the clock design.^[9] Apple later removed the design from its operating system with iOS 7.^[10]