A Design of Crowning to Reduce Ball Passage Vibrations of a Linear Guideway Type Recirculating Linear Ball Bearing

This paper deals with a design of crowning to reduce the ball passage vibrations of a linear guideway type recirculating linear ball bearing (linear bearing) with the crowning length L_C (1.2s ≤ L_C ≤ 1.7s, where s is the distance between the adjacent balls in the load zone). First, a fundamental condition to reduce the ball passage vibrations is provided. Second, a design method of the crowning by applying an approximate curve (an assumed functional formula) to the control points (satisfying the fundamental condition or being the intersection of straight and crowning areas of a raceway) is presented. Third, the design procedure is explained by giving an example. In the design example the power function crowning fits the control point best. In addition, the calculated amplitude for the power function crowning is lower than those for the circular arc crowning and the crowning of the commercial linear bearing. Finally, the validity of the presented design method is confirmed experimentally.