Knife rest for machine tool

A tool rest for a machine tool comprises a tool rest base, a lower cutter clamping plate is fixedly installed on the upper portion of the tool rest base, a supporting block is fixed to the middle of the lower cutter clamping plate, an upper cutter clamping plate is fixedly installed on the supporting block, and cutter grooves are reserved in the side edge of the upper cutter clamping plate and theside edge of the lower cutter clamping plate. A limiting nail is mounted on the upper cutter clamping plate through threaded connection, and the lower end of the limiting nail is inserted into the cutter groove; a ring groove is formed in the upper end face of the tool rest base, a rotating ring is installed in the ring groove, a rotating disc is fixedly installed at the upper end of the rotatingring, a gear ring is annularly arranged on the outer ring side of the rotating ring, a driving motor is installed at the bottom of the tool rest base, and the output end of the driving motor is inserted into the ring groove a