小轮

In order to solve the theoretical backlash problem of the teeth, which is crucial to the number of actual contact pairs of teeth in the research on multi teeth contact of crown gear coupling , the theoretical backlash of teeth flank with the concept of backlash angle is first time defined and described in the paper, and the minimization model of its variables is set up.

为解决鼓形齿联轴器多齿接触研究课题中的实际接触齿对数的关键技术轮齿理论间隙的问题，首次用间隙角的概念对轮齿理论间隙作了定义和描述；建立了该变量的极小化模型；对一鼓形齿联轴器作了实际优化计算，得出了鼓形齿联轴器多齿接触研究中计算实际接触齿对数所需的不同啮合状态下的最小间隙角

Taking the minimization of the tooth crown of a worm wheel and the maximization of transmission efficiency and the distance from the center as objectives,we establish the mathematical model for the multi-objective optimal design of worm transmission on the condition that the worm wheel and the worm transmission meet the requirements for load,strength and others.

以蜗轮齿冠体积最小、传动效率最高和中心距最小为目标，在保证蜗轮和蜗杆满足承载、强度及其它要求的前提下建立蜗杆传动多目标优化设计的数学模型。

The obstacle (the altitude of 900 mm) process for both sides of a planetary gear train was analyzed in ADAMAS. It is proved that the physical dimension of the planetary gear train, bodywork center position and attachment coefficient are the key effect factors. The driven moment, velocity and normal pressure sharply increased as each wheel surmounting obstacles, but they were moderate after the front wheel came over the obstacles. Another weaker pulse occurred when the rear wheel began climbing, and then the parameters reached a plateau.

行星轮系的结构尺寸、车体质心位置及附着系数对越障高度影响较大；各轮系越障时出现驱动力矩、速度和正压力急增的现象，前轮系的前轮越上障碍后，各参数值趋于平稳，后轮越障时又出现瞬时脉动，但脉动较小，后轮系也有相同的变化趋势，各轮的阻力矩和输出功率与正压力变化趋势相同。

The smallest dominant species were the Rotifera Brachionus forficula, Brachionus angularis and Polyarthra vulgaris, with an average length less than 100μm.

轮虫优势种中，体长最小的是剪形臂尾轮虫、角突臂尾轮虫和广布多肢轮虫等，它们的平均体长均小于100μm。

The numerical results show that:(1) the throughflow wake is considerably influenced by the tip clearance. The low-kinetic-energy fluid accumulated in the shroud/pressure side of the unshrouded impeller, but in the shroud/suction region for 0.0 tip clearance;(2) there possibly exists an optimum size of the tip-clearance which is not the zero tip clearance to make the flow loss minimized.

研究结果表明，(1)NASA低速大尺度离心压缩机半开式叶轮的低速尾迹区在压力面与轮盖的角区，而相应的闭式叶轮的低速尾迹区聚集在轮盖的中心位置；(2)数值实验表明，叶顶间隙并非越小越好，可能存在一个最优间隙，使得叶轮流动损失最小。

The objectives of this paper were to investigate the simulation and design of continuous multiple-station rolling forming process for a U-Section Steel Bar by CAE software-DEFORMTM Due to the limitation of elements number using a short strip 120mm went through all the stations to simulate the real continuous rolling forming on factory The roller gap was fixed as 0 30mm roll speed was 20 rad/sec and progressive angles were all equal for each rolling process which were the formed angle divided by by the number of station Three rolling processes were selected with 6 9 and 12 stations respectively During simulation processes two cases occurred Case A the strip was through a single station Case B the strip across two stations Because the strip laterals side was stretched and twisted during the process The model of case B closer to the practical process than case A and the calculated stress and strain on the tip of U section for case A were lower than these for case B by up to 15% From the result of case B for each process the stress for 12-station process was smallest 9-station process second and 6-station process next Because less-station can save larger cost and forming time but the bigger stress and strain for 6-station caused wrinkles on lateral sides not found on 9-station and 12-station Therefore 9-station process was a more suitable design than 12-station process smaller stretched and twisted and stress The progressive angles for 12-station was 7 5?

本文主要是以DEFORMTM有限元素软体模拟U型钢片连续道次成型与单一道次成型以确认单一道次模拟的是否可取代连续道次模拟之研究。因DEFORMTM 软体对於网格元素上的限制故使用较短素材120mm通过所有的成型站以模拟工厂实际连续成形方法。辊轮间隙固定为0 3mm；辊轮转速为20 rad/sec；弯曲角度的方法为将成型角度平均除以成型站数。有三种辊轮成型方式被选择分别为6站，9站，与12站。在模拟的过程中有两种现象会产生 Case A，素材通过单一成型站。Case B，素材会通过两个成型站。因为在模拟过程中素材的两端会有拉应力与扭力。Case B的模拟比Case A像实际的制程，并计算应力与应变在U型断面的Tip部中可发现Case A比Case B低约15%。从Case B的每站的结果可以得知，12站的成型应力最小，9站次之，6站最后。

The traditional pin-cycloid planetary drive has a series of essential advantages such as small volume, light weight, wide range of speed ratio, high efficiency, and quiet operating as well. On the other hand, it has a natural weak point that the tumbler bearing, which supports the cycloidal gear on the arm is placed inside the cycloidal gear, therefore the size of the bearing is restricted due to the geometry of the gear.

摆线针轮行星传动具有体积小，重量轻，传动比范围大，传动效率高，传动平稳且可靠等一系列优点，但它也有一薄弱环节，即转臂轴承处于摆线轮上输出机构的内部，径向尺寸受到限制，从而限制了摆线针轮行星传动更充分地发挥其承载能力。

Rotational modes are independent of the transverse support stiffnesses of the carrier, ring gear, and sun gear. Translation modes are similarly independent of the rotational support stiffnesses. Large contact ratio do not mean lower mesh force. If either the number of sun or ring gear is not multiple of planet gear, system will run effectively, with lower impaction of tooth mesh in and out.

研究表明：扭转支撑刚度的变化影响系统的转动模态，径向支撑刚度的变化影响系统的位移模态；齿轮间重合度大并不等于轮齿间的受力情况好；行星轮与内齿圈齿数不为行星轮个数的整数被时，轮齿的啮入、啮出对系统的冲击小，系统的效率高。

The next Morning I began to consider of Means to put this Resolve in Execution, but I was at a great loss about my Tools; I had three large Axes and abundance of Hatchets,(for we carried the Hatchets for Traffick with the Indians) but with much chopping and cutting knotty hard Wood, they were all full of Notches and dull, and tho' I had a Grindstone, I could not turn it and grind my Tools too, this cost me as much Thought as a Statesman would have bestow'd upon a grand Point of Politicks, or a Judge upon the Life and Death of a Man.

我有三把大斧和许多小斧（我们带了许多小斧，是准备与非洲土人做交易用的），但由于经常用来砍削多节的硬木头，弄得都是缺口，一点也不快了。磨刀砂轮倒是有一个，但我却无法转动磨轮来磨工具。为了设法使磨轮转动，我煞费苦心，犹如政治家思考国家大事，也像法官决定一个人的生死命运。

Because of the fact, the bearing capacity of the whole drive cannot be developed well enough. To improve the performances of the load-capacity, transmission efficiency, and reliability of mechanical drive, we originally developed some designs of the double crank ring-plate-type cycloid planetary drive. The new-type drive keeps all the natural advantages, which is of multi-tooth mesh, small mesh angle, and hardened tooth flank of gears. Moreover, The drive does not need the special output unit as the ring-plate-type drive does, so that the rigidity of the output shaft becomes much higher. Since the tumbler bearing is placed outside the cycloidal gear, the size of the bearing is no longer restricted to any extent.

为大幅度提高其承载能力、传动效率和可靠性诸指标，我们创新研究出来的多种结构双曲柄环板式针摆行星传动，其特点是不仅保留着原摆线针轮行星减速器同时啮合齿数多，总法向力与总圆周力间夹角小，摆线轮与针轮齿均为硬齿面等本质上的优点；而且又具有环板式传动省去输出机构且输出轴刚性好，转臂轴承移至行星轮外，从而传递的转矩可以成倍提高的优点。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。