Fastener of explosion-proof switch

The invention provides a fastener which can effectively prevent wrong operation of an explosion-proof switch. The fastener includes a bottom plate, a guide rail rack, a sliding sleeve, a sliding plate, a standing rod, a U-shaped sheath and a caution board. The guide rail rack and the bottom plate are in fixed connection. A guide rail is provided with positioning teeth thereon. The sliding sleeve sleeves the guide rail and is in sliding cooperation with the guide rail. The sliding plate is provided with a lock block on one side surface facing the bottom plate. The lock block is provided with two lugs thereon. An upper end of a tooth blade is sleeved inside a shaft and is in rotary cooperation with the shaft. The middle section of the tooth blade in engagement with the lock block. The sliding plate is provided with the standing rod thereabove. The top part of the standing rod is provided with the U-shaped sheath. One end of the sheath is provided with a standing pipe. The cross section of the standing pipe is p