Assembly type crankshaft assembly

The utility model relates to an assembly type crankshaft assembly which comprises a crankshaft and a balancing weight fixedly connected to a crank of the crankshaft through a fastener, a lightening hole is formed in the balancing weight, and the distance between the lightening hole and the root portion of the balancing weight is shorter than the distance between the lightening hole and the end portion of the balancing weight. The utility model has the advantages that the balancing weight and the crankshaft can be separately processed and then assembled; the strength and rigidity of the crankshaft can be guaranteed, the balancing weight can be used for achieving light weight and low cost, meanwhile, modeling limitation on the balancing weight is smaller, the mass center of the balancing weight can be made to be far away from the rotation center of the crankshaft, and the mass of the balancing weight can be reduced on the premise that the mass-diameter product is not changed. A balancingweight is not assembled