Rapidly-rotating underwater dicing knife rest

The utility model discloses a fast rotation underwater dicing knife rest which comprises a knife rest provided with blades and a channel, and further comprises first elastic pieces fixedly installed between every two blades, a partition cavity is formed between the multiple first elastic pieces, and the first elastic pieces move towards the outer ring of the knife rest. According to the fast-rotating underwater pelletizing knife rest, the gaps are sealed through the separation cavities, and the situation that plastic particles enter the gaps and are not prone to being discharged is avoided; meanwhile, when a large number of plastic particles are accumulated between every two blades, centrifugal force generated during rotation of the tool rest enables the arc top of the first elastic piece to face the outer ring of the tool rest, the plastic particles between the blades are pushed to the outer side of the tool rest to enter the water chamber, and interference of the plastic particles on rotation of the tool re