Process and Tool development to deburr cross-drilled holes

该项目的目标是以TRIZ(Teorija Reschenija Isobretatjelskich Zadatch--创新问题解决理论)为基础，开发新的刀具概念、尖端几何形状和方法，以实现交叉钻孔的可靠和自动去毛刺。基于TRIZ的开发方法是一种系统的、结构化的解决技术问题的方法。这一研究项目的前提是深入了解相交曲线与刀刃几何之间的关系。这将通过对不同直径的交叉钻孔的相交曲线、孔轴线之间的错位以及预钻孔的旋转进行完整的数学描述来实现。随后，将分析相交曲线的梯度以及通过预钻孔或交叉钻孔的进入策略。对于不同的相交曲线以及沿单个相交的圆周，梯度变化很大，因此导致了现有去毛刺工具在去除整个毛刺根部时遇到的常见问题。球体表示所有渐变，并可与沿轨迹的同步导向一起使用，以补偿相交曲线上的不同渐变。因此，一种可能的方法是使用球形或镰刀形的刀刃。用于预测沿相交曲线周长的毛刺高度的模型的实施防止了大毛刺的弯曲。该方法的有效性是基于从低毛刺形成区域开始的去毛刺过程。这种方法有助于可靠地去除毛刺。根据推导出的描述孔相交的数学方程，去毛刺工具将沿着相交曲线移动以去除毛刺。因此，将基于工具的方法和基于数字控制的方法相结合，以实现工具和相交曲线的同步移动。随后，对不同的进刀策略、进给速度和切割速度对二次毛刺高度的影响进行了实验研究。研究项目的最后一年集中于开发一种模型，以确定去毛刺刀具的工作范围，并调查刀具刃口的微观和宏观几何形状对二次毛刺的影响。

The aim of the project is the TRIZ- (Teorija Reschenija Isobretatjelskich Zadatch - Theory of Innovative Problem Solving) based development of new tool concepts, cutting edge geometries and methods for a reliable and automated deburring of cross-drilled holes. The TRIZ-based development method is a systematic and structured approach to solve technical problems. The prerequisite of this research project is a deeper understanding of the relationship between the intersection curve and the cutting edge geometry. This will be achieved through a complete mathematical description of the intersecting curves of cross-drilled holes with varying diameter, a misalignment between the axes of the holes as well as rotations of the pre-drilled hole. Subsequently, the gradients of the intersecting curves as well as entering strategies through the pre- or cross-drilled holes will be analyzed. The gradients vary strongly for different intersecting curves as well as along the circumference of an individual intersection, thus giving rise to the common problem existing deburring tools encounter when removing the entire root of the burr. A sphere represents all gradients and can be used in combination with a synchronized guide along the track to compensate the different gradients along the intersecting curve. Therefore a possible approach could be the use of a sphere- or sickle-shaped cutting edge. The implementation of a model used to predict the height of the burr along the circumference of the intersecting curve prevents the bending of large burrs. The efficacy of the method is based on the deburring process starting in areas of low burr formation. This method contributes to a reliable burr-removal. Based on the derived mathematical equations to describe the intersections of the holes, the deburring tool will be moved along the intersecting curve to remove the burr. Therefore a tool-based and a numeric control-based approach will be combined to achieve a synchronized movement of the tool and the intersecting curve. Subsequently, experimental investigations on the influence of different entering strategies, feed rate and cutting speed on the secondary burr height will be conducted. The final year of the research project focuses on the development of a model to identify the operating range of the deburring tool and to investigates the effects of the micro- and macrogeometry of the cutting edge on the secondary burr.