CONNECTED n°11
CONNECTED #11 | LEMO NEWS

X marks the Spot

XX series 3373-3386_HD

LEMO, inventor of the Push-Pull connector, is expanding its product range by adding, for the first time, a new series equipped with a bayonet coupling system, code name: X Series.

Internationally renowned for the high quality and reliability of its products, LEMO offers a wide range of circular Push-Pull and screwcoupling connectors. They are used in a large number of high-end applications, including military and motorsport, which traditionally would use bayonet coupling systems. It was exactly in response to requests from such customers, an Italian race car team in particular, that LEMO developed its new X Series.

As a first step, the X Series will be available with an aluminium shell in three sizes: XX, 0X and 1X, which have all been prototyped, field tested and laboratory validated. Before their release onto the market, planned for the first quarter of 2019, LEMO plan to complete even further testing and will expose the new range to “Gunfire” vibration, which is the benchmark in terms of testing the product’s resistance to extreme shock and vibration. “The X Series have been designed to offer the same characteristics as our M Series, the preferred connector for applications subject to extreme vibration” specifies Noman Hashemi, in charge of the development of the X Series. One of the first steps was to analyse which components from the existing product ranges could meet the specification requirements. Hence, the X Series have borrowed several features from the F and especially from the M Series connectors, which have already been widely used in motorsport applications. Therefore, the difference comes mainly from the usage patterns.

The principle of bayonet coupling is nothing new, since it has existed for over a century. However, LEMO goes further than most bayonet- type connectors that you’d come across on the market.

In order to ensure optimum ruggedness and durability, the locking pins that are normally inserted into the male connector are not separate items but machined directly into the shell. Moreover, in spite of their small size, all X Series connectors, including the smallest, are equipped with three pins instead of two.

“The XX reference of the X Series is probably one of the smallest in diameter of what you can find on the market.” adds Noman Hashemi. “This reduced diameter may represent a major advantage for certain applications and can make it possible for example to insert several connectors in a limited space.”

This small size is one of the greatest technical challenges taken up by LEMO. “Unlike a Push- Pull connector, where the inner groove of the female counter-part is straight, the bayonet coupling system requires a helical groove, which is particularly complex to machine in such a small part. Therefore, our production teams had to develop specific tooling to create this helical groove on the inner surface of the machined part.”

Lightweight, compact, watertight, shock and fuel resistant, the first three sizes of the X Series have been designed in aluminium to meet the specific requirements of motorsport applications. All three are available in two types of finish: knurled for standard use and arctic grip for applications where gloves are worn. The X Series will be subsequently developed in further sizes and in other materials, such as stainless steel or brass, depending on customers’ future needs