推力球轴承极端条件下“卡滞”机理的研究

发布时间：2018-07-17 00:55

【摘要】：本文针对球轴承在微重力、高低温、高真空等极端条件共同作用下存在的“卡滞”现象展开研究。以推力球轴承为研究对象，综合考虑其极端工况条件，，对其“卡滞”机理进行理论研究，依据理论研究结果，建立推力球轴承多体动力学接触有限元仿真的边界条件，运用有限元软件模拟其启动运转过程。理论研究以失重为线索，分析了轴承各个零件在有、无重力条件下的运动与受力状态，确立了滚动体、保持架的运动与受力状态在有、无重力条件下存在着本质差异，并确立其为研究对象；运用动力学及摩擦学基础理论对轴承在极端条件下的“卡滞”机理进行了理论研究，得出了“卡滞”机理：由于滚动体处于滚道空间内特殊区域和特殊综合条件下，在温度变化造成滚道空间变小，再次启动时转矩明显增大，从而产生“卡滞”现象，这种条件的出现是一种小概率事件；利用有限元软件建立了推力球轴承多体动力学接触有限元仿真模型，模拟了其在极端条件下的启动运转过程，在大量算例中，有1例出现了符合上述条件的情况，验证了理论分析的结果。为开展微重力条件下的轴承试验研究，本文提出了利用磁悬浮平衡重力的方法建立微重力条件的试验装置与标定装置，并对磁场中钢球及保持架受力分布等进行了仿真研究。本文提出了利用磁悬浮平衡重力的原理方案；通过有限元软件对滚动体、保持架在磁场中的受力进行仿真计算，得到了电磁铁对钢球及保持架的引力分布规律，探索了建立重力平衡的条件，验证了方案的可行性，同时为设计电磁场提供了理论依据。根据上述研究结果，初步设计了电磁铁结构、轴承试验机；为了纠正磁场力理论计算值的偏差，设计了标定装置，以期标定结果为试验装置参数调整提供实际依据。
[Abstract]:In this paper, the phenomenon of "stagnation" of ball bearings under the action of microgravity, high and low temperature, high vacuum and other extreme conditions is studied. Taking thrust ball bearing as research object, considering its extreme working conditions, the mechanism of "stagnation" is studied theoretically. Based on the theoretical results, the boundary conditions of finite element simulation of multi-body dynamic contact of thrust ball bearing are established. Finite element software is used to simulate the start-up process. Based on the clue of weightlessness, this paper analyzes the movement and force state of each part of bearing under the condition of having or without gravity, and establishes the rolling body. There are essential differences between the movement and force state of the cage under the condition of having or without gravity. The basic theory of dynamics and tribology is used to study the mechanism of "stagnation" of bearings under extreme conditions. The mechanism of "lag" is obtained: because the rolling body is located in a special area and special synthesis conditions in the raceway space, the raceway space becomes smaller and the torque increases obviously when starting again, which results in the phenomenon of "stagnation". The emergence of this condition is a small probability event, the finite element simulation model of multi-body dynamic contact of thrust ball bearing is established by using finite element software, and the start-up operation process of thrust ball bearing under extreme conditions is simulated. In one case, the results of the theoretical analysis were verified. In order to carry out the experimental study of bearing under microgravity condition, a test device and calibration device for establishing microgravity condition by using the method of maglev equilibrium gravity is put forward, and the force distribution of steel ball and cage in magnetic field is simulated. In this paper, the principle scheme of using magnetic levitation to balance gravity is put forward, the force of rolling body and cage in magnetic field is simulated by finite element software, and the law of gravity distribution of electromagnet to steel ball and cage is obtained. The conditions for establishing gravity equilibrium are explored, the feasibility of the scheme is verified, and the theoretical basis for the design of electromagnetic field is provided. According to the above research results, the electromagnet structure and bearing testing machine are preliminarily designed, and in order to correct the deviation of the theoretical calculation value of magnetic field force, a calibration device is designed to provide a practical basis for the parameter adjustment of the test device.
【学位授予单位】：燕山大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TH133.3

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