Fuel supply device

The invention belongs to the technical field of ship power systems, and discloses a fuel supply device which comprises a fuel injection valve, a fuel supply mechanism, a purge gas supply mechanism, a conveying pipeline and an air supply mechanism, and the fuel supply mechanism is configured to provide fuel for the fuel injection valve; the purge gas supply mechanism is located at the downstream of the fuel supply mechanism; the conveying pipeline comprises an inner-layer pipe and an outer-layer pipe which are coaxially arranged in a sleeved mode, an interlayer space is formed between the inner-layer pipe and the outer-layer pipe, the purging gas supply mechanism is configured to provide purging gas for the inner-layer pipe, the fuel supply mechanism, the purging gas supply mechanism and the fuel injection valve are communicated through the conveying pipeline, and the inner-layer pipe is configured to allow fuel to pass through; the air supply mechanism comprises an air source, and the air source communicates