Transfer of the method for noise reduction based on compressed air to fast-rotating tools, supplemented with a design optimisation of tool base and chip space geometries

DFG的研究项目“开发一种基于压缩空气的方法来降低旋转工具的噪音”证明，从经济的角度来看，通过施加额外的气流来有效地降低声级是可能的。结果表明，所开发的降噪方法在材料去除领域具有广泛的应用前景。为了在工业实践中使用，现在打算将这一基本研究方法应用于现代标准机床，并在操作和经济方面进一步发展。因此，这个转移项目的目的是实现和证明用压缩空气方法开发的降噪系统的生产适用性，以降低快速旋转工具的声级。计划的调查将显示该方法在工业应用中的适用性，以及设计和工艺条件对其有效性的影响程度。为了在材料去除过程的降噪方面取得最有希望的结果，压缩空气方法将在此得到刀具底座和切屑空间几何形状设计优化的补充。机床研究所制定了有关空气喷嘴系统和刀具基座和切屑空间的设计适应性的措施。这些措施将被视为本项目框架内的两种互补办法。在第一种方法中，从声学角度来看，通过在工具或切削刃的近场施加额外的气流，周围空气的特性得到了有利的改变。第二种方法是指在气动声学方面改善刀具几何形状（底座和切屑空间）的设计措施，同时不影响刀具在切削特性、加工精度、刀具寿命等方面的实际效率。这意味着切割边缘的几何形状保持不变。这两种方法将相互配合，以达到最大程度的降噪效果。最后，将编制一个计算机辅助程序，包括设计低噪声铣刀和使用空气喷嘴系统来有效降低快速旋转刀具的声音。

The DFG research project "Development of a method based on compressed air for reducing the noise of rotating tools" proved that it is possible, also from an economic point of view, to effectively reduce the sound level by means of applying an additional airflow. The results obtained show a broad range of applications in which the developed noise reduction method can be used in the field of material removal. For use in the industrial practice, it is now intended to adapt this basic research method to modern standard machine tools and develop it further with regard to handling and economy. Hence, the aim of this transfer project is to realise and prove the suitability for production of the noise reduction systems developed with the compressed air method for reducing the sound level of fast-rotating tools. The planned investigations will show the suitability of this method for industrial application and to what extent its effectiveness can be influenced by design and process conditions. To achieve the most promising outcome regarding the noise reduction of material removal processes, the compressed air method will be supplemented here with a design optimisation of the tool base and chip space geometries.The Institute for Machine Tools developed measures regarding the air nozzle system and the design adaptation of the tool bases and the chip spaces. These measures will be regarded as two complementary approaches within the framework of this project. In the first approach, the properties of the surrounding air are changed favourably from an acoustic point of view by applying additional airflows in the near field of the tools or the cutting edges. The second approach refers to design measures resulting in an improvement of the tool geometry (bases and chip spaces) in respect of aeroacoustics, yet without influencing the actual efficiency of the tool regarding cutting characteristics, machining accuracy, tool life, etc. This means that the geometries of cutting edges remain unchanged. The two approaches will be adapted to each other so that a maximum noise reduction can be achieved. Finally, a computer-aided procedure will be worked out including instructions for designing low-noise milling tools and using air nozzle systems to effectively reduce the sound of fast-rotating tools.