齿坯上下料桁架机械手结构设计与分析

Structural design and analysis of gear blank loading and unloading truss manipulator

【目的】为了满足某一齿坯数控加工生产线的实际工作需求,设计了一款可对两台具有不同加工工序要求的数控机床进行齿坯上下料的桁架机械手。【方法】首先对桁架机械手进行了总体设计并对其关键结构进行设计;其次通过ANSYS Workbench软件对桁架机械手工作过程中的极限位置进行静态分析,得到变形和应力云图,验证结构的可靠程度;最后再对桁架机械手进行模态分析,提取出前8阶固有频率与振型,并以此进行电机振动对竖梁末端连接法兰中心点的谐响应分析,得到中心点位移频率图,分析出不适宜桁架机械手工作的电机工作频段。【结果】极限位置最大变形量为0.751 mm,最大应力为22.627 MPa,满足设计要求;5~7 Hz、13~17 Hz、30~33 Hz、43~46 Hz频段不适宜作为桁架机械手工作的电机工作频段。【结论】本研究结果可为后续桁架机械手的控制系统设计提供理论依据。

[Objective] In order to meet the actual work requirements of a numerical control processing line of a gear blank, a truss manipulator was designed to load and unload the gear blank of two CNC machine tools with different processing requirements. [Method] Firstly, the overall design of truss manipulator was completed, covering its key structures;secondly, the limit position of the truss manipulator was analyzed statically by means of ANSYS Workbench software, and the deformation and stress nephograms were obtained to verify the reliability of the structure;finally, the modal analysis of the truss manipulator was carried out to extract the first 8 orders of natural frequency and vibration mode, and accordingly, the harmonic response of the motor vibration to the center point of the connecting flange at the end of the vertical beam was analyzed to obtain the displacement frequency diagram of the center point, and to figure out the working frequency band of the motor that was not suitable for the truss manipulator. [Result] The maximum deformation at the limit position is 0.751 mm and the maximum stress is 22.627 MPa, meeting the design requirements;the frequency bands of 5-7 Hz, 13-17 Hz, 30-33 Hz and 43-46 Hz are not suitable for being the working frequency bands of the motor in the truss manipulator. [Conclusion] The results of this study can provide a theoretical basis for the subsequent control system design of truss manipulator.