Clamping mechanism of machine tool achieving single minute exchange of dies (SMED)

The utility model provides a clamping mechanism of a machine tool achieving single minute exchange of dies (SMED). The clamping mechanism aims at solving the problem of low efficiency of SMED. The clamping mechanism is characterized by comprising a hydraulic clamping oil cylinder, a hydraulic clamping oil cylinder control system, a pull rod, a chuck and clamping jaws and further comprising a linear position sensor, wherein a detected part of the linear position sensor is fixed to the pull rod or a piston rod of the hydraulic clamping oil cylinder, the signal output end of the linear position sensor is connected with the feedback end of the hydraulic clamping oil cylinder control system, and the clamping jaws are stepped clamping jaws. The clamping mechanism has the advantages that in the process of SMED, the unfolding amplitude of the clamping jaws can be quickly changed under matching of the control system, and reliability of clamping workpieces of different specifications is guaranteed.