Analysis of the Cross-Sectional Shape and Wiping Angle of a Wiper Blade

The windshield wiper is a component that is closely related to safety because it plays an important role in ensuring the driver’s vision despite external factors such as rain and dust. Here, the mechanical properties of different types of blade rubber were evaluated using a miniature tensile test machine for a structural analysis of the types of wiper blade rubber used in automobiles. In addition, a compression set and the aging characteristics of each type of rubber were determined by comparing the mechanical properties and shape changes of the blade rubber after more than one year of use to the same blade rubber before use. Using the mechanical properties as measured by a tensile test, a nonlinear structural analysis of the wiper blade system was conducted using a 3D finite element method (FEM). The contact force distribution and wiping angle of the blade rubber under a static load were measured. According to the structural analysis, there is a difference in the wiping angle of more than 30° and a difference in the contact force distribution of more than 1.5 times between the new rubber and the old rubber. A sensitivity analysis was conducted using the design of experiments (DOE)-derived three main factors affecting the cross section of the blade rubber. Based on the main factors, the effects of the wiper blade’s cross-sectional shape on the angle and contact force distribution were analyzed using the response surface method (RSM). When a static load of 2 N is applied and when the width of the web reaches 0.75 mm, the length of the web is 0.9 mm, and the tip width is 0.65 mm, the contact force distribution range is reduced, and the wiping angle is in the normal range. The results of this study indicate that it is possible to predict the main factors and the design direction of the cross-sectional shape of a wiper blade.