Operating mechanism support, operating mechanism and circuit breaker

According to the operating mechanism support, the operating mechanism and the circuit breaker, the operating mechanism and the circuit breaker respectively comprise the operating mechanism support, the operating mechanism comprises a fixing plate and a mounting plate which are oppositely arranged, the fixing plate is provided with a fixing shaft and a blocking structure, the fixing shaft can be inserted into the mounting plate to be limited, the blocking structure is provided with a blocking face, and the blocking face is provided with a clamping groove. When the mounting plate and the fixing shaft are limited, the side, away from the fixing plate, of the mounting plate is limited by the blocking structure, and after the fixing shaft is inserted into the mounting plate, the mounting plate is limited on the fixing shaft through the blocking structure, so that the mounting plate is prevented from turning outwards and falling off, and reliable limiting of the mounting plate and the fixing shaft is guaranteed; th