1989 年 55 巻 1 号 p. 135-140
An infinite stiffness aerostatic thrust bearing with an active restrictor is proposed. The bearing surface has a central stepped region which functions as a surface restrictor. Because the stepped region is supported elastically by another aerostatic bearing incorporated into the thrust bearing, the depth of the step can vary according to the load applied. Consequently, the applied load is supported without changing the air film thickness on the land of the thrust bearing, and thus the bearing stiffness can be infinite. Therefore, this surface restrictor can be regarded as an Aerostatically-Controlled Restrictor (ACR). The influence of design parameters such as the depth of the stepped region and the stiffness of the stepped-region-supporting bearing is analysed by numerical calculations and experiments. From the experiments, it is shown that while avoiding the occurrence of pneumatic hammer, the thrust stiffness of the bearing with the ACR can be infinite.