Crankshaft and gear assembling device for punching machine

The utility model relates to a crankshaft and gear assembling device for a punching machine. The crankshaft and gear assembling device comprises a crankshaft, a gear and an auxiliary end plate, wherein an outer conical shaft is arranged at the end part of the crankshaft; an inner conical hole is formed in the center of a wheel hub of the gear; the inner conical hole is pressed into the outer conical shaft and is in interference fit with the outer conical shaft; an axial oil groove is formed in the outer conical shaft; a radial oil groove is formed in the outer wall of the outer conical shaft; one end of the axial oil groove extends to the outer end face of the outer conical shaft, and the other end of the radial oil groove is communicated with the radial oil groove; the auxiliary end plate is arranged at the outer end of the inner conical hole and is fixedly connected with the outer end of the outer conical shaft. By the change of a crankshaft and gear fit structure, the phenomena of fatigue damage and stress concentration which are caused by a key groove in the crankshaft are avoided, so that the crankshaft and gear assembling device for the punching machine has the characteristics of capability of bearing an impact load and an alternating load, large transmission torque and steady transmission; therefore, the bearing capacity of the crankshaft is improved, the intensity and the connection performance of a connection piece are enhanced, and the service life of the crankshaft and gear assembling device is prolonged.