Double-air-circuit rotary braking type safety detector for gantry crane

The utility model provides a double-air-circuit rotary braking type safety detector for a gantry crane. The double-air-circuit rotary braking type safety detector for the gantry crane comprises a foot valve which is fixed to the floor of a cab through a bolt, wherein one end of the foot valve is connected with an air pressure measurement device, the other end of the foot valve is connected to a pipeline of a braking air pipe, an air compressor is connected to one end of the pipeline, two pipelines are connected to the other end of the pipeline in parallel, one of the pipelines is composed of a first assistor, a first pressure switch and a first brake cylinder, the first assistor, the first pressure switch and the first brake cylinder are connected in sequence through an oil pile, the other pipeline is composed of a second assistor, a second pressure switch and a second brake cylinder, the second assistor, the second pressure switch and the second brake cylinder are connected in sequence through an oil pipe, a programmable logic controller which is used for executing control commands is arranged inside a machine room, and the two pipelines are controlled by the programmable logic controller. The double-air-circuit rotary braking type safety detector for the gantry crane has the advantages that braking is rapid, operation is easy and convenient to conduct, safety and reliability are guaranteed, and the efficiency is high. During work, a drive just needs to tread a foot switch slightly in order to achieving braking of a rotating mechanism immediately, and then goods can be stopped and suspended above a position where the goods need to be placed. The double-air-circuit rotary braking type safety detector for the gantry crane can be applied to other port facilities and is broad in application prospect.