振动筛两平移两转动并联机构的运动学分析

Kinematical Analysis of Virbrating Screen on a Kind of 2T-2R Parallel Mechanism

为适应不同作物清选的需要,提出了一种可满足多种作业需要的空间振动筛思想,并设计了该振动筛的主体机构。该振动筛采用四自由度并联机构作为主体机构,能方便地调节振动筛的振幅和振动方向。该并联机构包含4条支路,其中2条支路为R-R-P型结构,另外2条支路为R-R-R-R-P型结构。以该机构的动平台为振动筛的筛面,能实现2个方向的移动,以及绕2个方向轴线的转动。应用转换矩阵对该机构进行运动学建模,并给出了该机构运动学的正解和反解。结果表明可以将此机构应用于振动筛。

An idea of spatial vibrating screen was presented to meet the different needs in screening crops, and its main body has been designed. A kind of four degrees-of-freedom parallel mechanism has been used by the screen as the main body. It could adjust the amplitude and the vibration direction of the vibrating screen conveniently. This parallel mechanism included four legs, where two legs were types of R - R - P, the others were R - R - R - R - P. The moving platform of this mechanism, used as a screen platform, could achieve a movement in two durations and a rotation around two directional axes. The kinematics modeling method of this mechanism was studied by using conversion matrix, and the kinematics positive and inverse solutions of this mechanism were presented. The result indicated that this mechanism could be applied in the vibrating screen.