Flexible gear and harmonic speed reducer with flexible gear

The flexible gear comprises a flexible gear body, transmission teeth are arranged on the periphery of the flexible gear body, a protruding anti-moving limiting structure is arranged on the outer wall and/or the inner wall of the flexible gear body, the anti-moving limiting structure is arranged in the middle of the flexible gear body, and the anti-moving limiting structure and the flexible gear body are integrally formed. Therefore, the purpose of preventing the flexible gear from moving in the working process is achieved through an anti-moving limiting structure located in the middle of the flexible gear body, specifically, the anti-moving limiting structure on the outer wall of the flexible gear body is in limiting fit with an annular groove in a steel wheel, and the anti-moving limiting structure on the inner wall of the flexible gear body is in limiting fit with an annular groove in a wave generator. The problem that the two ends of the flexible gear body are abraded is avoided, the failure rate of the fl