Hot coiling box uncoiling device and uncoiling control method thereof

The invention discloses a hot coiling box uncoiling device and an uncoiling control method thereof. The hot coiling box uncoiling device comprises an uncoiling arm and an uncoiling perching knife positioned on the end socket of the uncoiling arm, wherein the uncoiling perching knife is composed of two triangle shovelling blades which are symmetrically connected together through a connecting shaft, and the opposite inner sides of the two triangle shovelling blades are respectively provided with a strip-shaped groove along the uncoiling direction of the uncoiling perching knife; the two strip-shaped grooves are connected through a shifting shaft, the two ends of the shifting shaft and the corresponding strip-shaped grooves respectively form shifting pairs, one side, which is connected with the triangle shovelling blades, of the shifting shaft is respectively sleeved with a round roller which can freely rotate, the shifting shaft arranged between the two round rollers is connected with a connecting rod, and the