共查询到18条相似文献,搜索用时 471 毫秒
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利用高速陶瓷电主轴热稳态和热瞬态的热力学模型,研究了热态性能对零件加工精度的影响,结合某高速精密加工中心的主轴单元,用有限元计算和分析了温度场及热平衡时间,将结果与实验进行比较,证明其有效性。结果表明:高速陶瓷电主轴在运转时热量主要来源于内置电机的损耗发热和轴承摩擦生热。前后轴承、定子和转子是热量集中处,最高温度出现在转子与定子间间隙处,为62.23℃,需采用良好的散热措施进行散热;精密磨削加工前应提前启动机床,进行10 min的预热,使机床各部件达到热平衡,减少热变形带来的加工误差,提高加工质量。该建模方法以及热力学模型可为高速电主轴的优化设计和研制提供一定的参考。 相似文献
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详细介绍了高速电主轴内部的发热特性,包括轴承的摩擦生热、电机运转生热以及内部空气与高速旋转主轴的粘性摩擦生热,分析了电主轴内部的热传导机制及冷却机制,建立了比较通用的电主轴热特性计算的理论模型,并以实际项目的电主轴为例进行了有限元分析,对实际工作中的电主轴结构设计具有较强的指导意义。 相似文献
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针对电主轴的热分析主要集中于内置电机为感应电机的电主轴,对内置电机为永磁型的研究甚少的现状,基于电磁学和摩擦学理论对永磁型电主轴的热源进行了计算,并使用传热学经典理论计算电主轴热边界条件。以此为基础在Ansys Workbench中建立电主轴有限元分析模型进行热态分析,根据求解结果进行热-结构耦合分析。结果表明,由于永磁同步电主轴有着转子不发热的固有特性,导致热量主要集中在前后轴承处并使主轴产生热变形。 相似文献
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为研究高速滚珠轴承电主轴的热特性对其性能的影响,计算轴承的热源生热并进行热特性仿真。研究轴向载荷和转速对接触角的影响规律,进而采用局部热计算方法计算轴承的热损耗。结果发现,轴承的旋转速度对其热损耗的影响比轴向载荷作用更明显,并且滚珠的自旋摩擦是轴承生热的主要形式。结合热源生热计算结果,运用ANSYS对一定转速的空载电主轴分别进行稳态热分析和瞬态热分析,发现电主轴的最高温度点出现在内置电机转子的中心区域。将稳态热分析结果加载到有限元模型进行热-结构耦合分析,发现最大轴向位移出现在主轴的最前端,最大轴向应力则出现在前轴承球与外滚道的接触区域。设计空载电主轴温升测定实验,验证仿真结果的正确性。 相似文献
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以Setco 231A240型高速电主轴为研究对象,考虑了内置电机的损耗生热和轴承的摩擦生热,计算了电主轴各部分之间的传热系数,利用有限元软件Workbench建立电主轴有限元模型,分析得到了电主轴在不同因素影响下的温度场分布,基于电主轴热-结构耦合关系分析得到了温度影响下电主轴的热变形。仿真结果显示,较低转速下电主轴转子温度最高,转速对电主轴温度影响较大;电主轴头尾部热变形较大,主要为轴向变形。最后,将温度场仿真数据与实验数据对比,验证了仿真分析的准确性。 相似文献
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S.-M. Kim S.-K. Lee K.-J. Lee 《The International Journal of Advanced Manufacturing Technology》2002,19(8):551-557
This paper investigates the effect of bearing assembly tolerance on spindle-bearing compliance. In a high-speed spindle system,
the bearing characteristics are influenced significantly by the initial assembly tolerances and the thermal deformation of
the bearing surroundings. In the very early stage of spindle operation, spindle bearings could be under hazardous conditions
owing to the rapid change of the internal pressure resulting from thermal deformation or centrifugal force-oriented deformation.
The bearing’s internal clearance also may be changed by the operating conditions such as external load, rotational speed,
and operating cycle time. To determine the initial tolerance and the optimal cooling regimen, a comprehensive dynamic modelling
and analysis of a high-speed spindle system in terms of bearing pressure, bearing compliance, and heat generation is required
with consideration of those effects. Moreover, in order to predict spindle characteristics in operation, all of these parameters
should be monitored and recalculated in real-time. For this purpose, very simple and effective equations are suggested, representing
the bearing stiffness in accordance with the thermal deformation. Most former bearing analyses were based on the Hertzian
contact model, without considering the radial elastic defor-mation of the races. In this paper, analytical and experimental
investigations of the bearing compliance are conducted with consideration of both the elastic deformation of the race and
the thermal deformation of the housing in terms of the bearing stiffness. The experimental results show the effectiveness
of the proposed equations, which are simple and useful for fast calculation of the bearing stiffness by dynamic simulation. 相似文献
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S.-M. Kim S.-K. Lee 《The International Journal of Advanced Manufacturing Technology》2005,25(11-12):1061-1070
This paper presents a simulation method for predicting thermo-elastic behaviours of spindle-bearing system and an optimization procedure for housing design parameters in relation to various spindle-bearing operating and surrounding conditions such as assembling tolerance, geometric dimension, cooling condition and thermal deformation. The numerical formulation of transient thermo-elastic behaviours as a function of major spindle-bearing system design parameters is developed using the design of experiment methodology. The spindle-bearing analysis program has also been suggested in this paper. The suggested modelling and optimization method not only considers thermal deformation or heat transfer, but eventually it includes the nature of thermo-elastic interaction within spindle, bearing, housing and surrounding conditions in terms of formulating the objective function describing thermo-elastic characteristics such as friction moment, heat generation, contact mechanism, thermal displacement, assembly tolerance change, bearing internal clearance and spindle stiffness change and the dynamically changing operating conditions of the spindle. In order to substantiate the method, this paper shows a numerical example of formulation and optimization results for spindle housing design parameters with consideration of thermo-elastic behaviours as the thermal displacement, the preload increase, and the preload fluctuation. 相似文献