SELECTION ISSUE ON THE BALANCE SHAFT FOR A INLINE 4-CYLINDER ENGINE AS HOW TO LOCATE BOTH SUPPORTING BEARING AND UNBALANCE MASS

摘要

PURPOSE: A positioning method of an unbalanced mass of a balance shaft for an inline 4-cylinder engine and a bearing is provided to prevent the rattle of gear teeth due to the change of the rotating torque of the balance shaft in high speed and to prevent the generation of noise and vibration. CONSTITUTION: A positioning method of an unbalanced mass of a balance shaft for an inline 4-cylinder engine and a bearing comprises the following steps. The amount of deformation energy by the bending of a balance shaft is produced. Kinematic energy by the rotating inertia couple forces is produced. Possible position combinations of supporting bearings according to the location variation of the equivalence unbalance mass are produced. An optimum location and a mass ration of the supporting bearing and the unbalanced mass which minimize the bending deformation and the momentum is produced by finding an object function value of each case. The mass ratio of a rotor and the unbalance mass of the balance shaft is 2~4:1. The supporting bearing and the unbalance mass are located in the 20±1 and 80±1 respectively when the total rotor length is 100.