Main cone nut automatic tightening and hole aligning device

The utility model discloses a main cone nut automatic tightening and hole aligning device. A display interface is connected with a PLC; a converter motor (48) is connected with the PLC by a frequency converter; a brake gear (43) is connected with the PLC by a current driver; a pretightening force sensor (4) is connected with the PLC by an A/D convert module after passing an amplifier; a control panel is connected with the PLC; an electromagnetic valve and a travel switch are connected with the PLC; a nut encoder (46) and a flange encoder (60) are connected with the PLC; and a displacement sensor (51) is connected with the PLC by the A/D convert module after passing the amplifier and an angle encoder (53) is connected with the PLC. The main cone nut automatic tightening and hole aligning device overcomes the defect that the prior art can not monitor the alignment between a nut notch and a screw pin hole, causes the nut notch to conveniently and correctly align to the screw pin hole, has high tightening efficiency and can be widely applied to the assembly field of main cone nuts.