Abstract:

A new grinding strategy was proposed for crankshaft based on boxer located double wheels,where two wheels were placed respectively at both sides of the crankshaft part in the normal plane.Five-axis linkage scheme was adapted for the motion control of the two separated wheel frames and the rotation of workpiece,hence to suppress the drawback of workpiece deformation on the roundness precision of both bearing journals and pin section,which were introduced by the unbalance grinding force of single side grinding mode.Thus the excessive dependence of central support frame in traditional tangential point tracing grinder was eliminated,and the entire procedure of precise machining was achieved for crankshaft part in single grinder from roughcast stage to fine situation.The grinding force balance model of bearing journal and pin journal was analyzed kinematically,as well as the influence of following motion deviation of the double wheels.By computer simulation and practical investigation,the presented grinding strategy emerges good characteristics in the precise manufacturing of crankshaft part,such as easy clamping, high precision and short processing interval.

Key words: crankshaft, following grinding, double wheel, boxer located, motion model

摘要：

研究了一种双砂轮水平对置曲轴磨削方法，通过将两片砂轮在法向平面上水平对置于曲轴两侧，采用五轴联动方式同步驱动两副独立砂轮架与工件旋转轴,对连杆颈和主轴颈进行精密磨削加工以抑制单边磨削力导致工件变形对圆度的不良影响,消除了传统切点跟踪磨削方式对中心架支撑的过度依赖,实现了在单台磨床上从毛坯到精密成品的一次加工成形。从运动学角度分析了双砂轮水平对置磨削曲轴主轴颈与连杆颈的磨削力平衡机理,以及双砂轮随动偏差对磨削力抵消过程的影响机制;运动模型计算机仿真与双砂轮水平对置曲轴磨床样机试验表明:基于双砂轮水平对置的曲轴随动磨削方法在曲轴精密加工应用中具有工件夹紧简便、磨削精度高和生产节拍快等显著优点。
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关键词: 曲轴, 随动磨削, 双砂轮, 水平对置, 运动模型