采煤机截齿分析与优化

基于采煤机截齿破煤原理,列举了采煤机截齿失效形式,并根据采煤机力学分析,对截齿的载荷和受力进行了分析,利用模拟软件对采煤机的结构进行仿真模拟,进一步优化采煤机的结构。对比优化前后相关参数,采煤机的工作性能大大提升,延长了采煤机使用时间。     

采煤机的异常分析与诊断控制系统的研究

针对现有的采煤机故障诊断依靠人工巡查、定期保养所存在的效率低、可靠性不足的缺陷,提出了一种新的采煤机异常分析与诊断控制系统,该系统能够对采煤机运行过程中的关键运行参数进行实时监测,自动对采煤机的运行状态进行判断并对异常原因进行分析和报警,极大提升了采煤机运行的可靠性。     

基于ADAMS的MG2型采煤机行走机构的研究

针对采煤机在综采作业时由于煤矿井下地质条件复杂、采煤机综采作业时受载荷冲击较大而导致其四轮行走机构频繁发生损坏的问题,以MG2型采煤机的行走机构为例,通过对MG2型采煤机销轨与采煤机截深关系分析,建立了仿真分析的数学模型,利用ADAMS仿真分析软件对采煤机行走机构与销轨在不同条件下的啮合特性进行了仿真分析,为优化采煤机行走机构、提升工作可靠性和使用寿命提供理论和技术支持。     

采煤机振动特性研究

为研究复杂煤层赋存条件下采煤机的振动特性,针对引起采煤机振动的三方面因素进行分析,从采煤机振动信号的识别以及振动信号时域、频域分析两方面分析了采煤机振动信号的分析思路,为实现煤矿井下采煤机截割煤岩界面的自动识别提供理论基础。     

采煤机调高机构的机液联合仿真分析研究

通过对采煤机机液调高机构结构及工作原理的分析,合理地简化了液压系统执行油缸和采煤机摇臂之间的联动关系,通过简化的联动分析,建立了采煤机机液调高系统的数学模型,并利用AMEsim及Matlab仿真分析软件,建立了采煤机调高机构的机液联合仿真分析模型,对调高机构的工作过程进行了联合仿真分析,结果表明:采用联合仿真分析的方法能够直观地对采煤机调高系统工作时的机液特性进行模拟,对提升采煤机设计水平、优化系统结构、提升采煤机使用的经济性具有十分重要的意义。     

基于ADAMS的采煤机调高液压控制系统的可靠性分析

在对采煤机调高液压系统工作原理进行分析的基础上,利用ADAMS仿真分析法对调高液压系统的工作过程进行仿真分析,根据分析结果进行针对性的优化设计,为优化采煤机调高液压系统结构、提升采煤机工作可靠性提供理论、技术支持。     

电牵引采煤机电控系统的研究与改进

对采煤机控制系统发展现状进行分析,以及对采煤机控制系统需求进行分析研究,提出了一种以双DSP为基础的电牵引采煤机控制系统,并完成了系统总体方案的改进设计,为采煤机控制系统的进一步研究改进提供参考和指出方向。     

采煤机摇臂结构的优化分析

通过对采煤机摇臂结构的分析,研究了摇臂在工作时所受的动载荷的情况,在此基础上建立采煤机摇臂的三维结构模型,并将其导入到Ansys中进行仿真分析,得出采煤机摇臂结构的弱点,然后利用优化设计的思想对采煤机的摇臂结构进行优化,并对优化前后的结构进行仿真分析。分析结果表明,优化后采煤机摇臂整体的重量降低了约3.1%,优化的效果十分的显著。     

煤矿采煤机摇臂齿轮的优化设计与分析

为改进采煤机摇臂齿轮工作过程中设备出现的故障,并查找其原因,对采煤机摇臂各级齿轮的运动进行了运动学分析,同时利用Ansys DesighXplorer对采煤机摇臂进行了优化设计,为采煤机摇臂齿轮的改进提供了重要的依据。     

基于虚拟样机技术的采煤机调高液压系统的仿真

对采煤机液压调高系统进行了理论建模分析,在ADAMS中建立液压系统模型,应用液压调高系统与机械部分耦合技术进行了采煤机液压调高仿真与分析,验证了该采煤机液压系统模型的精确性。     

基于CATIA的手动搬运车三维建模及装配仿真

高效环保的手动搬运车在超市、实验室等环境被广泛地应用,因此基于CAD/CAE的一体化软件CATIA对手动搬运车建立零件模型、装配模型和虚拟样机模型,实现了手动搬运车的仿真分析,解决运动过程中可能存在的干涉问题,提高设计质量和设计速度。     

不同喷射速度下厢体气膜减阻效果的实验研究

研究厢体表面渗透空气流的喷射速度对气膜在空气中的减阻效果的影响。通过气膜发生系统控制有气膜厢式车实验模型的气膜空气喷射速度，在30 m/s的流动空气速度下，于可调速拟层流风力发生装置中开展与无气膜厢式车实验模型的对比测阻实验，比较不同喷射速度下，有气膜厢式车实验模型的受阻情况。实验结果表明，在流速恒定的拟层流空气流体环境下，厢体表面渗透空气流有效地降低了厢体所受的空气阻力，且在一定范围内，减阻率随喷射速度的增大近似呈线性增长。     

基于虚拟样机技术的折叠翼厢式车液压开启系统的仿真研究

折叠翼厢式车是一种新式厢式车,给货物的装卸带来了极大的方便。本文介绍了这种厢式车的基本原理,并运用 UG建立了三维实体模型,然后导入机械动力学仿真软件ADAMS中,建立起液压与机械一体化虚拟样机模型,并进行了动 力学仿真,预见了设计方案的可行性,为物理样机的试制提供了参考。     

一种货车尾部的飞翔导流罩仿真设计

为了有效减小厢式货车在高速行驶过程中的气动阻力,提出了基于3Dmax建模的高速公路厢式货车导流罩设计,命名为飞翔导流罩。以高尔夫球表面的凹坑设计为设计思路,以改进类似设计的弊端为目标,运用3Dmax建模设计此导流罩。对该模型进行分析模拟后,结果表明该设计在高速行驶厢式货车的减组中,具有广泛的应用前景。     

范德华力对硅基微悬臂梁抗粘附稳定性的影响

通过在硅微悬臂梁与基底表面上涂覆低表面能的憎水性OTS(CH3(CH2)17SiCl3)膜,以除去接触面间的表面张力;把梁与基底均接地,以除去接触面间的静电力,研究仅有范德华力作用时,硅微悬臂梁结构的抗粘附稳定性.根据两接触面均为粗糙表面的微观实际接触模型,在接触表面产生塑性变形的情况下,计算范德华粘附能大小,并分析表面形貌对其影响,得到粗糙表面接触的微梁抗粘附临界长度.     

轻型工具车货物装卸升降装置的结构设计

以江淮箱式货车为例,设计一套货物装卸装置,通过测量江淮康铃第二代厢式货车的尺寸,确定升降装置的安装位置,用三维建模和运动仿真测试,为工具货物升降装置的设计提供理论分析和设计方法,对轻便型工具货车升降装置的普遍应用具有重要意义.     

On the Transition from Bulk to Ordered Form of Water: A Theoretical Model to Calculate Adhesion Force Due to Capillary and van der Waals Interaction

The adhesion force due to capillary interaction between two hydrophilic surfaces is strongly dependent on the partial pressure of water and is often calculated using the Kelvin equation. The validity of the Kelvin equation is questionable at low relative humidity (RH) of water, like in high vacuum and dry nitrogen environments, where water is only present as layers of several molecules thick at the surfaces. A model from ordered to bulk form of water has been developed using the Brunauer, Emmett, and Teller adsorption model. The results show that the adhesion force calculated using the Young–Laplace and Kelvin equations at low (5–30 %) RH is underestimated. The total adhesion force shows changes when the RH is changed from 0 to 100 %. In dry conditions, at RH below 10 %, the total adhesion force is contributed by the van der Waals interaction due to solid–solid contact. The total adhesion force then increases and remains constant being equal to the superposition of van der Waals interaction due to solid–solid contact and van der Waals interaction due to adsorbed water layers on the surfaces. The total adhesion force further increases slowly with the increase in RH incorporating capillary forces and then decreases at very high RH due to screening of van der Waals forces. This change in adhesion force occurs from solid–solid interaction to ordered form of water at low RH and from ordered form to bulk form of water at high RH along with the screening effect of van der Waals interaction. The results have been compared with the experiments and it has been seen that at small length scales, the model is in agreement with the existing experimental data. However, at large length scales roughness of the surfaces should be taken into account.     

The systematic design and fabrication of a three-chopstick microgripper

In this study, we constructed a new type of gripper for micron-sized objects using piezoelectric multi-layer benders. This new gripper is composed of three chopsticks: two are designed to grip micro-objects, and the third is used to help grasp and release the objects. It is well known that a micro-object is much easier to grasp than to release. Electrostatic, van der Waals forces and surface tension between the chopsticks and object are believed to be the main causes of adhesion. We introduced a third auxiliary chopstick to overcome these surface effects and to reduce the electrostatic forces between the object and chopsticks. All three chopsticks were made of tungsten wires with ends sharpened by etching, which minimises the van der Waals effect. We constructed a three-chopstick gripper for micro-objects and tested its functionality by holding and releasing a 100-micron diameter object. The experiment showed that the third auxiliary chopstick functions effectively.     

Adhesion Analysis Considering van der Waals Force in a NanoSized Region Using the Boundary Element Method

Recently, micro- and nanomachines for microelectromechanical systems and the mechanism of bio-adhesive pads have attracted great interest. Nanoscale structures are affected by forces such as the van der Waals force, even though they are neglected in large-scale structures. In this paper, the van der Waals force is introduced to a boundary element method (BEM) program for analyzing adhesion in arbitrarily shaped bodies. The van der Waals force is described by a nonlinear function of the distance between two surfaces in close proximity, and the adhesion and repulsion forces vary greatly within the atom equilibrium distance. Therefore, it is difficult to obtain a solution for the simultaneous equation in the BEM. We propose a method to compute the body deformation and apply it to the adhesion between a cylinder and a flat, rigid substrate. The solution is compared with previously published theoretical results, and the validity of the algorithm for approaching the solution is demonstrated. Further calculations for the adhesive contact of softer and harder cylinders with a rigid substrate are conducted.     

微型汽车门锁系统耐惯性力的分析

以某微型客车门锁为例,分析了门锁在汽车行驶过程中所承受的惯性力.