共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
3.
为研究RV减速器柔性因素对传动精度的影响,以BX40E减速器为研究对象,综合考虑支承弹性变形及齿轮接触弹性变形对系统动态传动精度的影响,建立多自由度RV减速器动力学模型,提取系统的动态响应;探究变载、变速条件下各级传动接触及支承变形对动态传动误差的贡献量,量化分析BX40E减速器传动误差对各柔性因素的灵敏度。结果表明:动态传动误差随负载增加而增加,输出转速平稳性随负载和转速增加而下降;二级传动的接触变形对减速器传动误差贡献最大,柔性支承贡献次之;传动误差对“摆线齿轮-曲拐”处及“行星架-曲柄轴”处支承刚度的敏感度高于其他支承处,对二级齿轮接触刚度的敏感度高于一级传动。 相似文献
4.
随着航天技术和深空探测的发展,传统的脂润滑材料已难以满足谐波减速器在真空宽温区的润滑需求,固体润滑涂层是一种非常理想的空间润滑方式,具有较宽的温度使用范围,且润滑性能受工况的影响也较小,广泛应用于空间运动机构。目前固体润滑谐波减速器在苛刻空间环境下的使役性能(传动精度和传动效率)还鲜有报道,通过物理气相沉积技术分别在XBS-40-100型和XBS-60-120型谐波减速器制备MOSTP&MOSTP和DLC&MOSTP两种固体润滑涂层,并对润滑前后的谐波齿轮减速器的传动精度、传动效率及真空高、低温适应性进行对比研究。研究结果表明:谐波减速器的传动误差不仅没受到润滑涂层的影响,其传动精度还远优于脂润滑的同型号谐波减速器;固体润滑谐波减速器具有优异的温度适应性,XBS-40-100型和XBS-60-120型谐波减速器在-90℃~100℃温度范围内,传动效率分别为69.4%~82.8%和66.2%~86.7%,远高于全氟聚醚(-90℃,效率在30%左右)和多烷基化环戊烷(-90℃,效率基本在15%左右)润滑的同型号谐波减速。系统研究了固体润滑谐波减速器的使役性能和温度适应性,可... 相似文献
5.
6.
齿轮在传动的过程中会因为各种因素产生传动误差进而影响到齿轮传动的工作精度、震动噪声、可靠性以及使用寿命等。在研究由齿轮加工误差、轴偏心和装配间隙三个传动误差主要来源的基础上,综合各单元误差建立了齿轮传动链的传动误差函数。同时对一典型二级齿轮减速器进行了仿真计算,结合频谱分析对其传动误差进行初步的分解与溯源,得出误差占比分布状态和误差主要影响因素,为齿轮减速器产品设计提供了一种误差预测方法并指出制造安装时需主要保证精度的传动环节。 相似文献
7.
为解决工业机器人谐波减速器使用过程中传动误差超限故障诊断问题,建立伺服电机和谐波减速器的机电仿真模型,分析减速器间隙增大对驱动电机电流产生的影响。构建工业机器人谐波减速器机电系统实验平台,采集不同传动误差谐波减速器对应的驱动电机电流信号。利用电机电流信号,提出结合梅尔倒频谱和支持向量机,以及结合梅尔倒频谱和概率神经网络的2种故障诊断方法。基于多种指标综合分析比较上述2种故障诊断方法,结果表明:结合梅尔倒频谱和支持向量机的谐波减速器传动误差超限故障诊断方法综合性能优于结合梅尔倒频谱和概率神经网络的方法。 相似文献
8.
采用HP5423A分析仪,对谐波齿轮减速器进行了振动实验测试及频谱分析,由振动响应的频率结构确定了此类传动机构的振动特征,即减速器的扭振和弯振情况,并定性地分析了各种振动产生的原因 相似文献
9.
以RV减速器为研究对象,分析了零部件的加工、装配误差对RV减速器传动的作用形式,将LIN的平移扭转耦合模型和质量弹簧误差等价原理相结合,建立该系统动力学传动误差的数学模型并进行求解;并以数学模型参数为基础,基于ADAMS动力学仿真软件建立了含有各类误差的三维模型并进行了仿真分析,通过对仿真的RV减速器输入输出速度数据的测试分析得到传动误差为2″~40″,与数学模型计算结果相似;通过对RV减速器数学模型计算的传动误差和ADAMS仿真的传动误差频谱图分析,得出影响传动误差大小的主要因素是二级摆线针轮传动。仿真结果验证了数学模型的准确性。 相似文献
10.
11.
Deng-Kui Zhang Guo-Qing Wang Ai-Ping Wu Ji-Guo Shan Yue Zhao Tian-Yi Zhao Dan-Yang Meng Jian-Ling Song Zhong-Ping Zhang 《金属学报(英文版)》2019,32(6):684-694
In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone. 相似文献
12.
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。 相似文献
13.
After nearly two years'tense construction the first phase of industrialized base of Shenyang Research Institute of Foundry 《中国铸造》2008,5(1):63-64
After nearly two years' tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry (SRIF), located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation. 相似文献
14.
Z. Sun S.L. Zheng Y. Zhang 《金属学报(英文版)》2007,20(3):187-192
Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process. 相似文献
15.
R. González-Martínez 《金属学报(英文版)》2007,20(4):235-240
The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke. 相似文献
16.
R.Z. Wu Z.K. Qu B.D. Sun D. Shu J. Wang 《金属学报(英文版)》2007,20(3):193-198
The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results. 相似文献
17.
B.W. Zhang B.W. Li 《金属学报(英文版)》2007,20(2):129-138
On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes' collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process. 相似文献
18.
An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films(NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be *5.0 J/m2 for Cu/Cr, *4.1 J/m2 for Cu/Ta,*2.8 J/m2 for Cu/Mo, *1.1 J/m2 for Cu/Nb, and *1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models. 相似文献
19.
Chen Wang Bei-Bei Wang Dong Wang Peng Xue Quan-Zhao Wang Bo-Lv Xiao Li-Qing Chen Zong-Yi Ma 《金属学报(英文版)》2019,32(6):677-683
A 17 vol% SiCp/Al–Mg–Si–Cu composite plate with a thickness of 3 mm was successfully friction stir welded(FSWed) at a very high welding speed of 2000 mm/min for the first time. Microstructural observation indicated that the coarsening of the precipitates was greatly inhibited in the heat-affected zone of the FSW joint at high welding speed, due to the significantly reduced peak temperature and duration at high temperature. Therefore, prominent enhancement of the hardness was achieved at the lowest hardness zone of the FSW joint at this high welding speed, which was similar to that of the nugget zone. Furthermore, the ultimate tensile strength of the joint was as high as 369 MPa, which was much higher than that obtained at low welding speed of 100 mm/min(298 MPa). This study provides an effective method to weld aluminum matrix composite with superior quality and high welding efficiency. 相似文献
20.
Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems. 相似文献