Amfibia

In the Soviet clock industry an Amfibia watch was what the west would call a "Diver" watch. Produced in great quantities for the Soviet and Russian military, these watches gained great popularity worldwide. The Vostok Amphibia or Raketa Amphibia are Russian diving watch created respectively in 1967 and 1968 for the USSR's navy.

The Amphibia creation was led by Vostok's chief of their new design bureau. The objectives were to create a watch that was competitive with contemporary diving watch such as the Blancpain 50 Fathoms, the Rolex Submariner, and the watches using the compressor case, and to create a watch that could operate reliably at the temperature and pressure of a depth of 200 meters (and later 300 meters). The chief designers were Mikhail Fedorovich Novikov and Vera Fedorovna Belova.

According to Mikhail Novikov, the name “Amphibia” was chosen in a contest among the watch factory’s employees. It was named after the amphibians for their quality of being equally comfortable on land and in water.

On the way to creating the first Soviet diver watch, the developing team had to go through quite a lot of difficulties. Since similar foreign counterparts were patented it was impossible to simply copy them and everything had to be developed from scratch. The team had to design a special technology for glass, start manufacturing special rubber, and adapt to working with steel instead of brass.

In 1967 the first batch of the Amphibia watches rolled off the factory line, it could withstand depths up to 200 meters. Due to the high popularity of the model, in the 70s, the factory together with GLAVCHASPROM started developing a new model that could be used by divers in the 300-meter depth. This new watch had to go through a tough test in the field during a maritime exercise in the North Sea. The divers practiced submarine rescue while wearing Amphibia watches.

In 1975 a Soviet cosmonaut Georgy Grechko wore the Amphibia watch during the Soyuz 17 mission to the Salyut 4 space station which led to the even higher popularity of Amphibia watches among people all over the world.

The Amphibia is the embodiment of possibly the most simple concept for creating a watertight case. The basic principle is to use the outside pressure to create the seal needed to prevent water from entering the case. The further the case sinks, the higher the outside pressure, the higher pressure is exerted on the case, creating a dynamically tighter seal. This is opposed to the idea where you create a case that creates the pressure to withstand 20ATM of pressure no matter what pressure it experiences (1 ATM at sealevel, for instance). This is a design similar to the western compressor case, a patent for which was filed at least as early as 1954, and granted in '56(US pat. 2,737,009). The advantage of the compression design is that you do not need to tighten any of the seals to a pressure that would withstand 20ATM, it also eliminates several pieces required to create such a seal.

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