The Device for Measuring the Stiffness of the Bearings

Abstract

This article deals with the design of the equipment for bearing stiffness determination of the shaft. The other part of the thesis is concerned with an experiment of the equipment. The knowledge of the bearing stiffness is important for finite element analysis (FEA) to help determine the correct type and size of the gear modification in the car gearbox. At present, this stiffness is not included in FEA software. The stiffness of the bearings is investigated statically and dynamically with rotational shaft. This is one of the requirements on the device. The first part of the article is focused on the design of the device for the bearing stiffness determination. The second part elaborates on the measurement methodology and the evaluation of the result from the measurements. The result of the measurement is not the rigidity of the bearings, but the displacement of the shafts and the tilting of the inner ring. In order to determine the bearing stiffness of these results, it is necessary to know the theoretical displacement of the shaft point in which it is measured. Shaft bearings are replaced with ideal joints. This substitution is done in FEM calculation of the shaft. The final stiffness is determined from the measured data.