The invention of Push-Pull


Many companies share the Push-Pull connector market. However, only one of them can boast of having invented them. This is how it happened.

As dusk is falling over the forest, Léon Mouttet sets up his camera close to a bush, pulls the cables of his flash and hides them as best as possible. The avid photographer wants to capture images of wild animals in their nocturnal life. Once the automated mounting readily set, he goes home. At dawn, huge disappointment: animals have indeed passed by, but their feet got tangled in the cables, disconnecting the device. The same has happened before, which makes Léon Mouttet upset about fragile connections. There must be a better solution!

In 1954 LEMO enters the connector market. The use of transistors enables the miniaturisation of electronic devices, requiring new connectors. Léon Mouttet senses the market to gain, but with which type of connectors? During a trade show held in Zurich that year, he is not satisfied by the existing interconnection systems. Screw connectors are too slow and not very practical. Bayonet systems are too rough and not secure enough. There must be a better solution!

The inventor sets to work. He wants to create a new locking system, easy and quick to use, as well as perfectly safe. At first, he is inspired by cigarette lighters of cars, easy to connect and disconnect using a single hand. Too rough and bulky. He then imagines a system with three inner latches that click into place when the connector is mated and open only when you pull on an outer ring. All it takes is a split second and two fingers. It is perfection itself.

Léon Mouttet presents his innovation to one of his customers, the Swiss Post and Telecommunications. The State-owned enterprise had been buying his electric contacts, they also need thousands of connectors for call centres. Operators connect and disconnect at a high rate, so ease-of-use is paramount. The very easy-to-use and safe self-latching connector created by LEMO raises immediate interest.

This coaxial 75 Ohm is the first product of the first LEMO Series, the S Series. A few years later, a 50 Ohm variant is created for the prestigious CERN (The European Centre for Nuclear Research), also among the early users.

These first models are so successful, that today, 65 years later, LEMO continues to sell coaxial 75 Ohm S Series. It also continues to provide the CERN with complete 50 Ohm cable assemblies with S Series – these products are known and recognised all over the world.

So, Léon Mouttet hit the nail on the head: his creation meets immediate requirements and has enormous potential. LEMO had already developed a multi-contact version with a half-moon insulator when, in August 1957, the inventor files a patent for his “electric contact plug”.

Immediate and increasing success. The Push-Pull system – the name attributed subsequently underlines its ingenious simplicity – has become a new connector standard. LEMO has never stopped improving it since, positioning itself more and more as a leader in high-performance solutions for demanding applications.

Léon Mouttet’s sketches from 1956 have generated a market grossly estimated at 1 billion dollars.  A multitude of companies sharing it, from small or middle-sized to giants whose Push-Pull connectors represent only one of their divisions. However, only one company can claim to be its inventor: “LEMO, the original Push-Pull connector”.