共查询到20条相似文献，搜索用时 31 毫秒
1.
陈健 《鞍山师范学院学报》2001,3(3):66-70
以普通圆柱蜗杆传动的蜗杆头数、模数、螺旋升角为设计变量，以蜗轮齿冠体积最小、传动效率最大、润滑条件最好为目标函数，应用模糊理论对普通圆柱蜗杆传动进行模糊优化设计与实例验算。 相似文献
2.
基于齿轮形金钢面修磨轮 ,TI蜗杆才能被精修磨 ,由此形成一种 TI蜗杆与渐开线斜齿轮的啮合传动型式 .本文对于这种新型传动副 ,建立了数学模型 ,推导出了若干基本方程式 ,并且进行了齿面接触分析 .理论分析表明这种蜗杆传动具有许多优点 . 相似文献
3.
Dynamic characteristics analysis of a misaligned rotor-bearing system with squeeze film dampers 总被引：1，自引：0，他引：1
In this paper, a dynamic model is established for a two-stage rotor system connected by a gear coupling and supported on ball bearings with squeeze film dampers (SFDs). The nonlinear dynamic behavior of the rotor system is studied under misalignment fault condition. The meshing force of the gear coupling is calculated considering the deformation of the tooth caused by torque transmission and dynamic vibration. The contact force between the ball and race is computed based on the Hertzian elastic contact deformation theory and the elastohydrodynamic lubrication theory. The supported force of SFD is simulated by integrating the pressure distribution derived from Reynolds’s equation. The equations of motion are rewritten in non-dimensional differential form, and the fourth-order Runge-Kutta method is employed to solve the nonlinear dynamic equilibrium equations iteratively. To verify the validity of the dynamic model and the correctness of the numerical solution method, the experimental power spectra of the rotor system under various misalignment degrees are compared with the analytical results. The effects of several important parameters, such as the lubrication of the ball bearing, the centralizing spring stiffness, the radial clearance of SFD, and the misalignment of gear coupling, on the dynamic characteristics of the rotor system are investigated and discussed mainly focusing on the system stability. The response spectra, bifurcation diagrams, and Pointcaré maps are analyzed accordingly. These parametric analyses are very helpful in the development of a high-speed rotor system and provide a theoretical reference for the vibration control and optimal design of rotating machinery. 相似文献
4.
徐戊矫 《重庆大学学报(英文版)》2003,2(2)
1. Introduction The double-envelop hourglass worm gearing is characterized by multi-tooth line contact and good lubrication condition. It has high load-carrying capacity and is often built in heavy-duty machines. Like other line-contact gear drive, it is sensitive to manufacturing errors, misalignment errors and load-dependent deformations, which cause the tooth end contact and large transmission errors [1]. The classic theory for meshing analysis of a gear drive overlooks diverse errors and l… 相似文献
5.
A parametric study on the contact stress of half toroidal continuously variable transmission 总被引：2，自引：0，他引：2
Nabil Abdulla Atti QIN Datong SHI Wankai LI Huaying The State Key Laboratory of Mechanical Transmission Chongqing University Chongqing P.R. China Faculty of Engineering Helwan University Matari Egypt College of Agricultural Engineeri 《重庆大学学报(英文版)》2003,2(2)
1. Introduction A toroidal continuously variable transmission (CVT) that uses a traction drive to transmit torque has a vastly larger torque capacity than a conventional CVT. This transmission technology has attracted considerable interest owing to its capability in substantially improving vehicle fuel economy and power performance [1]. The half toroidal CVT transmits torque by means of shear resistance of the traction fluid film taking advantage of the property of the fluid solidificatio… 相似文献
6.
To investigate the cage stability of high-speed oil-lubricated angular contact ball bearings, a dynamic model of cages is developed on the basis of Gupta’s and Meeks’ work. The model can simulate the cage motion under oil lubrication with all six degrees of freedom. Particularly, the model introduces oil-film damping and hysteresis damping, and deals with the collision contact as imperfect elastic contact. In addition, the effects of inner ring rotational speed, the ratio of pocket clearance to guiding clearance and applied load on the cage stability are investigated by simulating the cage motion with the model. The results can provide a theoretical basis for the design of ball bearing parameters. 相似文献
7.
Selective laser melting (SLM) is one type of additive manufacturing which produces metal parts by powder bed fusion. Since the materials undergo repeated and sharp heating/cooling cycles, the SLMed parts have unique microstructures. The relations among SLM processing parameters, resultant microstructures, and mechanical properties have been investigated by many researchers. However, the wear performance of SLMed materials under various contact conditions has not been carried out until recently. This paper is a presentation of previous and recent research related to wear performance. This is a crucial aspect if SLM is to be expanded to produce friction pairs. Wear rates and mechanisms of the SLMed materials under dry, boundary lubrication, cavitation erosion, and corrosion conditions are discussed and compared with conventionally processed (CP) materials. SLMed materials benefit from fine grains and high hardness, which have higher wear resistance than CP materials. Moreover, a unique tribo-layer on the surface of the SLMed part is found to protect the bulk material under boundary lubrication conditions. An optimized combination of processing parameters increases part density, which further improves the wear resistance. Future work includes studying the influence of pores on the deforming and lubricating behaviors from dry conditions to different lubrication regimes. The final target is to actively control the processing parameters to obtain desirable material properties for improving wear performance. 相似文献
8.
滚动轴承最小油膜厚度的分析计算研究 总被引：1，自引：0，他引：1
滚动轴承最小油膜厚度的准确计算对于滚动轴承疲劳寿命的精确估算非常重要,考虑影响滚动轴承最小油膜厚度的参数并对其进行了研究,通过Matlab回归分析得出了在热弹流润滑条件下新的接触点处的滚动轴承最小油膜厚度计算公式,并对此公式进行了显著性检验,证明此公式在一定条件下是正确可行的。 相似文献
9.
Elastohydrodynamic Lubrication Studies on Effects of Crowning Value in Roller Bearings 总被引：1，自引：0，他引：1
CHENXiao－yang SHENXue－jin 《上海大学学报(英文版)》2001,5(1):76-81
The purpose of this paper is to present a comparison of numerical calculations and experiment results of optical interferometry in finite line contact for the elastohydrodynamic lubrication(EHL)problem of Lundberg‘s profiled cylindrical roller under the conditions of flooded state,moderate load and material parameter.It shows clearly the effects of crowning value on the variations of oil film shape and thickness.The agreement between numerical analysis and experiment results is very good.The results indicate there must be an optimum crowning value that will induce the thickest and most even oil film in EHL state for a given working condition,and this value is larger than the design value in dry contact state for the same working coditiona. 相似文献
10.
非接触式章动传动机构是一种新型的传动装置。设计一种采用磁场、磁力作为传动介质,兼顾磁力传动和章动传动优点的传动装置,研制该传动机构样机并对其进行传动比实验测试。结果表明,非接触式章动传动机构可以实现机械接触式章动传动的功能,机构传动比稳定,为解决章动传动振动、噪声、齿轮磨损、润滑油液污染等问题提供了一种有效手段。 相似文献
11.
研究静液挤压过程流体动力润滑状态形成的条件,推导静液挤压过程工件与模具表面间润滑油膜厚度的计算公式．通过Ｒｅｙｎｏｌｄｓ 方程和塑性加工润滑理论推导了形成流体动力润滑的临界速度计算公式和润滑油膜厚度的计算公式,并对上述公式进行了实验验证．由临界速度计算公式所计算出的理论数值和实验所测数值基本吻合,该临界速度计算公式可作为静液挤压过程中是否形成流体动力润滑判据;润滑油膜厚度的变化往往对工模具表面间的摩擦系数、挤压过程的稳定性有很大程度的影响,可以根据本文提出的润滑油膜厚度的计算公式结合实际工况条件通过合理调整工模具各参数的数值以使得油膜厚度值达到一个理想的数值,从而对静液挤压过程进行优化设计． 相似文献
12.
案例教学是面向高职院校信息安全技术类课程实践性的有效教学方法.为了满足"信息安全基础"课程病毒知识案例教学的需要,设计了一个基于当前流行的飞客蠕虫病毒的查杀实战案例.该教学案例涵盖了病毒诊断、检测、清除和验证等蠕虫病毒查杀的完整过程.实践证明,案例教学是提高信息安全课程学生认知与创新能力的一种有效教学模式. 相似文献
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14.
李镇伟 《廊坊师范学院学报(自然科学版)》2008,8(5):39-40
由于蠕虫病毒具有极快的传播速度知巨大的破坏能力,每次爆发都严重扰乱了人们对计算机与网络的正常使用。通过分析网络蠕虫病毒的危害及其传播特征,设计了基于honeyd的未知蠕虫检测与预警插件,该插件可集成到honeyd系统中,部署到网络上进行未知蠕虫的检测与预警。 相似文献
15.
周翰逊 《沈阳教育学院学报》2006,8(2):144-145
首先阐述了本系统用到的基于ICMP的蠕虫检测方法以及相同通讯模式的蠕虫检测方法，然后介绍了本系统的结构模型，最后介绍了该系统的三个主要组成部分。 相似文献
16.
蜗轮、蜗杆组成的运动副常用于减速传动机构中,蜗杆的齿形较大,在切削时很难把握．通过改进刀具结构,采用“双弹簧圈”结构、组合结构等,通过旋转螺旋升角,保证刀尖的基面与螺旋方向垂直,保证粗精车切削过程切削角度相等,有利于强力切削,减小切削振动,防止扭转,避免蜗杆加工中的“扎刀”现象,从而提高了成品质量和生产效率． 相似文献
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18.
本文以平面二次包络环面蜗杆传动为实例,应用数值方法研究空间啮合问题。通过模拟蜗杆磨削过程和蜗轮滚切过程,生成以一组平行平面曲线定义的蜗杆曲面及与之共轭的蜗轮齿面,观察设计参数和加工参数对蜗杆磨削区域大小的影响。这一方法为空间啮合传动曲面检测及预测啮合质量提供了数据基础。 相似文献
19.
对蠕虫检测与主动防御技术进行深入研究,讨论Aegis模型,探讨利用snort进行蠕虫误用检测的研究思路和实现方法。仿真实验证明：Aegis系统具有良好的自适应性和开放式结构,有效结合了蠕虫检测与主动防御技术,对蠕虫攻击具有高检测率和低误报率,并能及时有效地防范蠕虫危机。 相似文献
20.
QIU Yong-you KANG Shuang-yang PENG Yun-feng YANG Ping HUANG Zi-qiang 《重庆大学学报(英文版)》2016,15(4):139-148
The purpose of the study concerns the measurement of worm’s helical angle by a coordinate measurement machine in the ambient industrial environment. The novel measurement method and sampling strategy were described firstly. This method used the coordinate measurement machine to measure both of the worm gear’s left and right surfaces. The worm surface was reconstructed based on the measured data of all the sampling points. Then a middle cylinder was established to truncate the fitted worm surfaces, and the truncated spiral lines were straightened to calculate the helical angle. The measurement uncertainty of worm’s helical angle was evaluated by taking the difference of calculated helical angles along the truncated spiral lines on both the left and right side surfaces of the worm. Twenty-four measurement experiments show that the maximum measurement error of the proposed method is 0.105, and the measurement error ratios are all less than 3.5?. The result means that the measurement method can realize the precision measurement of worm’s helical angle and can be employed in the generally industrial application. 相似文献