エアダンパ付き可変磁気抵抗形磁気スラスト軸受の研究 : 第2報, エアダンパの解析

抄録

This paper describes the analysis of the air damper used for the variable reluctance magnetic thrust bearing. We previously investigated the variable reluctance magnetic bearing and noted that this magnetic bearing has many advantages compared with other types of bearings : neither the high-pressure gas nor the control circuit are needed. However, this bearing does not generate a damping force by itself and the motion of the rotor is unstable without a damping force. Therefore, some mechanism which generates the damping force is essential to the operation of this bearing. The air damper accompanies the bearing to supplement the damping force and consists of the neumatic capacitor and the neumatic resistors. The chamber arranged between the rotor and the fixed elements operates as the neumatic capacitor. The narrow radial gaps between the rotor and the fixed elements operate as the neumatic resistors. In this paper the theoretical analysis of the air damper is carried out. Also, an experimental analysis is performed and the results are compared with the theoretical predictions. In the suspension consisting of the magnetic bearing and the air damper, a damping factor as large as 0.2 is achieved.