Force-measuring device of hoisting tool of crane based on fiber grating sensor

The invention discloses a force-measuring device of a hoisting tool of a crane based on a fiber grating sensor, comprising a rotary lock, a fiber grating sensor, a demodulation instrument and a load processer, wherein one end of the fiber grating sensor is fixed on the axis of the end part of the rotary lock, the output end of the fiber grating sensor extends outside the upper end part of the rotary lock and is connected with the input end of the demodulation instrument through a conductor, the output end of the demodulation instrument is connected with the load processor and is used for transmitting signals after being demodulated to the load processor, and the load processor is used for processing digital singles of the demodulation instrument to be a load result of the rotary lock and outputting the result. The rotary lock is formed by rebuilding the conventional rotary lock. The upper end of the conventional rotary lock is provided with a fine long hole along the axis of the rotary lock, the bottom part a