摘要： 轴承的摩擦力矩对陀螺马达惯性运转时间具有重要影响，合理调整预紧力大小可减低轴承的摩擦力矩。为定量描述加载预紧力的马达轴向位移特性，建立了基于线性弹簧的马达轴向等效模型，并采用“两砣法”对轴承预紧力进行测试，提出的马达轴承预紧力调整方法可将实际预紧力控制在目标范围内，从而合理地降低轴承摩擦力矩。实测结果表明，马达轴承预紧力调整方法可有效提高陀螺马达的惯性运转时间。

关键词：马达；惯性运转时间；预紧力；轴向等效模型

Abstract: The run-down time in gyro motor was greatly influenced by the bearing friction torque. The reasonable adjustment of the pre-tightening force was an effective approach to reduce this friction torque. The axial mechanical model of the gyro motor based on the linear spring theory was represented for quantitatively describing the axial displacement characteristics loaded by pre-tightening force. Tow-weight method was used to test the pre-tightening force in bearings. The proposed adjustment method keep the pre-tightening force within target range, thus the bearing friction torque can be reduced reasonably. The results of experiments are proved that the proposed method is effective to increase the run-down time in gyro motor.

Key words: motor；run-down time；pre-tightening force；axial mechanical model