The locking or coupling type is a mechanical device with which plugs or connectors are protected so that the contact connection between the plugs or plug and socket is ensured even under mechanical stress. They are mechanical devices with which both parts of a plug connection are pressed firmly together. There are many different techniques for locking. All of them ensure that the plug contacts are securely connected to each other with high conductivity.
One such mechanical device can be a shackle of elastic material used to press one connector part against the other, as is often used with multipole connectors. Such a shackle l atch can be slid over the connector part only when the connector is fully mated.
Slide locking is another locking technique for connectors. When the connector is fully mated into the receptacle, small sliders are slid over the domed portion of the connector housing, ensuring a tight mechanical connection.
Another locking technique is screw locking, also called twist locking, which is used in RF connectors and FO connectors. This is available as a screw locking system in which one part of the connector has a thread that is screwed together with a union nut, thus connecting both parts of the connector firmly and HF-tight. Examples of coaxial connectors with screw locking are the TNC connector, UHF connector and the SMA connector. FO connectors with screw locking include the FSMA connector, the FC connector and the DIN connector.
Bayonet locking also works with rotary technology. In this technique, the two connector parts are inserted into each other. The bayonet ring is then rotated to the latched position. This technique is used by the BNC connector, TNC connector, mini BNC connector and the ST connector, among others.
There is also the pull-off locking system, where the plug is released by pulling axially on the coupling ring, and the push-pull locking system. This is a self-locking quick-release coupling. The push-pull coupling is locked and unlocked by the coupling ring being moved axially. The ESCON connector, LX.5 connector, E-2000 connector, LC connector, SC connector, F3000 connector, MU connector and various others work with this locking technology.