Dustproof circuit board of medium-voltage frequency converter

The utility model provides a dustproof circuit board of a medium-voltage frequency converter, which belongs to the technical field of frequency converters and comprises a workbench and a sealing assembly arranged on the outer wall of the workbench, and the sealing assembly comprises a sealing shell, a skirt edge, a restraining shell, a mounting groove, a reset spring, a base, a driving bevel gear, a knob, a driven bevel gear, a lead screw and a fixing pipe. The sealing shell is slidably embedded in the inner wall of the workbench, the skirt edge is fixedly arranged on the edge of the inner wall of the sealing shell, the mounting groove is formed in the top of the outer wall of the workbench, and the restraining shell is fixedly arranged on the outer wall of the sealing shell. Through the sealing assembly, the sealing shell can be stably opened and closed, the circuit board main body embedded in the mounting groove is prevented from directly contacting the external environment, dust is prevented from being acc