【作者】 程果；

【导师】 庄森；

【作者基本信息】 郑州大学 ， 机械制造及自动化， 2012， 硕士

【摘要】 空间RCCR机构是有着广泛运用前景的机构。目前对这种机构的研究也取得了一定的研究成果。它可以作为一种较为新型的联轴器使用。它的轴线夹角理论上范围为0度到180度之间。在考虑到实际情况和机构实体的情况下,这个范围会略有缩小。这种机构不仅可以做为联轴器使用,还可以运用到泵、马达等结构中。在其多对传力杆的情况下,对力的分担使得机构的整体受力比较平衡,而且此机构结构相比来说比较简单,连接全都是低副,使得机构运动更平稳、耐磨损性能更好。本文采用示力副法对机构在整体坐标系下进行力的分析与求解。首先对空间RCCR机构静力学的分析与求解。在求解过程中,忽略构件间的摩擦力与构件所受的重力且构件间的连接为无间隙连接。由于空间RCCR机构在三对传力杆受端面力的情况下,每对传力杆与其它传力杆不是同时受端面力,所以在求解过程中进行分段进行讨论。相对于每对传力杆来说,其受端面力的转角总和为180度,但是从整体来说每相隔60度机构的受力情况就会产生变化,所以在计算时每隔60度对机构受力进行计算。由于端面力是变化的,所以根据轴8所受力矩平衡求出随着转角变化的输入力矩。然后求出机构各个运动副所受的约束力和约束力矩。在静力分析求解的基础上,又对机构做了动力上的分析与求解。在求解时,考虑到了各个构件所受的惯性力的影响,仍然采用示力副法在整体坐标系下进行求解,解出各个运动副所受的约束力与约束力矩。在SolidWorks环境中建立了空间RCCR机构的三维模型,由于空间RCCR机构的三对传力杆属于柔性体,所以该机构不适合在SolidWorks环境中进行动力学仿真分析。因此将该模型导入ADAMS中进行动力仿真分析。得出仿真数据并绘出各个运动副所受到的约束力和约束力矩随机构结构参数变化曲线图,并与理论计算所得出的结果进行对比,对比结果表明两者非常吻合。分析了空间RCCR机构各个运动副所受约束力和约束力矩之间的相互影响关系,其中传力杆相连接的旋转副所受到Z方向上的力存在着一定的力的分配关系,并且三个旋转副相互影响,Z方向所受的力直接影响到所在构件其它运动副所受的约束力及约束力矩。分析得出主要机构参数对改善机构受力的影响。其中传力杆夹角及机构的偏心距对机构受力影响比较大,得出了增大夹角可以减小机构的受力等结论。更多还原

【Abstract】 The Spatial RCCR is a mechanism with wide application prospect. So far, the research on it has obtained some achievements. It can be used as a new coupling structure. The theoretical scope of the shaft angle is (0°,180°). The scope will be narrowed slightly taking the actual situation and the structure of entities into consideration. This mechanism not only can be used as a coupling, but also be applied to pumps, motors and other structures. Under multiple pairs of dowel bars, this mechanism can keep the overall force more balanced by sharing the force. What is more, it’s structure is relatively simple. The connections are all lower pairs, which make the mechanism motion more stable and the better abrasion resistance.This article carries out the force analysis and solution by show the force pair method in the whole coordinate system. First, the statics analysis a nd solution to the Spatial RCCR is done. During the solution, the friction of the components and the gravity of the components are ignored. Meanwhile, the components connect by gapless connection. For the Spatial RCCR, when there are three pairs of dowel bars bearing the end surface force, because each pair of dowel bars and other dowel bars did not bear the force at the same time, so we discuss for segmentation during the solution. For each pair of dowel bar, the intersection angle of the end surface force sum to180degrees, but the force will be changed for every60degrees on the whole. So the force is calculated by every60degrees. As the end surface force is changing, the input torque changing with angle is calculated according to the moment balance of shaft8. Then the restraint force and restraint moment are calculated for each kinematic pair. Based on the static analysis and solution, the dynamic analysis and solution is added. During the solution, taking into account the effect of inertia force for every component, the restraint force and restraint moment for each kinematic pair are still calculated by show the force pair method in the whole coordinate system.The3D model of space RCCR is established in the SolidWorks environment. Because the three pairs of dowel bars in Spatial RCCR mechanism are flexible bodies, it is not suitable to make dynamic simulation analysis in the SolidWorks environment for this mechanism. So the model is imported into ADAMS to make dynamic simulation analysis. Then, the simulation data can be got as well as the curve of the structural parameters changing with the restraint force and restraint moment. And. compared with the theoretical calculation data, the result showed that they were consistent.This article also presents the mutual influence relationship of the restraint force and restraint moment for each kinematic pair. There are force distribution relations among the Z direction forces of the revolute joint connected with the dowel bar. What’s more, the three revolute joints affected mutually. The Z direction force affect the restraint force and restraint moment of other kinematic pairs in its component directly. The analysis shows the influence of the main mechanism parameters on improving the mechanism force. The influence of the dowel bar angle and the eccentricity on the mechanism is relatively large. And some conclusion is come out such as the increased angle could reduce the force of the mechanism, etc.更多还原