Device and method for measuring inner diameter of locking ring of main connecting rod bushing of helicopter engine

The invention relates to the technical field of locking ring inner diameter measurement, and discloses a helicopter engine main connecting rod bushing locking ring inner diameter measurement device and method, and the device comprises a leveling part which comprises a bushing; the two measuring parts are arranged at the two ends of the leveling part; and a measuring mechanism. In the embodiment of the invention, the leveling part is enabled to construct a horizontal detection state in the inner diameter detection area of the locking ring, then the two measuring parts enter the inner diameter detection area of the locking ring respectively, and the fixed measuring part is enabled to carry out determination in the inner diameter detection area of the locking ring; then the sliding measuring part performs self-adaptive correction adjustment movement in the detection area of the inner diameter of the locking ring, the fixed measuring part and the sliding measuring part select two symmetrical positions in the dete