A study on the development of a deformable rubber variable preload device

One of the important element technologies for achieving high-precision in machine tool spindles is bearing preload technology. Recently, various preload methods have been used in machine tool spindles. However, there are some drawbacks for applying them to spindles. Also, all previously applied methods cause problems in applications due to complexity in its system, difficulty in precision control, high installation cost, processing error, and installation error. To reduce costs in its system by simplifying its structure, a variable preload device is proposed using rubber pressure. The operability in a preload device using rubber is the main focus of the work. Hyperelastic analysis is carried out for verifying the characteristics of the rubber in this study. An experimental system has been fabricated and tested, and the results of the tests are compared with the analytical results. For verifying the characteristics of the rubber used in this study, the rubber is selected from commercial products. It is shown that the variable preload device proposed in this study is applicable to machine tool spindles.