Uses
The first documented use of this type of fitting (without the name "bayonet") may be by Al-Jazari in the 13th century, who used it to mount candles into his candle-clocks. This type of fitting was later used for soldiers who needed to quickly mount bayonets to the ends of their rifles, whence the name.
Many cameras with interchangeable lenses use a bayonet lens mount to allow lenses to be changed rapidly and locked accurately in position. Camera lens mounts usually employ stronger flattened tabs rather than pins, though their function is the same.
Bayonet electrical connectors are used in the same applications where other connectors are used, to transmit either power or signals. Bayonet connections can be made faster than screw connections, and more securely than push-fit connections; they are more resistant to vibration than both these types. They may be used to connect two cables, or to connect a cable to a connector on the panel of a piece of equipment.
The coupling system is usually made of 2 bayonet ramps machined on the external side of the receptacle connector and 2 stainless steel studs mounted inside the plug connector’s coupling nut. Several classes of electrical cable connectors, including audio, video, and data cables use bayonet connectors. Examples include BNC, C, and ST connectors. (The BNC connector is not exactly as described in this article, as the male, not female, connector has the slots and spring.)
Many types of light bulb are fitted with integral bayonet connectors.
Read more about this topic: Bayonet Mount