1. Introduction <br> <br> from the 1980's, with the rapid development of modern manufacturing technology, metal cutting into the high-speed cutting, represented by stage of development. Due to the obvious technical advantages of high-speed cutting technology, it has been widely used in industrial manufacturing fields such as automobiles, airplanes and molds in industrialized countries, which has produced huge technical and economic benefits and shows the development of modern manufacturing technology in the 21st century. It has an important position and broad application prospects.
"High speed cutting" is still a developing relative concept. For different workpiece materials and different processing steps, the required cutting speed is not the same. Generally, the cutting speed (or feed rate) can be increased by 5 to 10 times compared with ordinary cutting into the high-speed cutting category.
The realization of high-speed cutting needs to be based on the latest technological achievements in related fields such as machine tools and tools. At present, high-speed cutting is mainly used for cutting machining using rotary cutters such as milling cutters, boring tools, and hole machining tools on machining center machines. The spindle speed of the machining center machine used is usually above lO000r/min. When the spindle speed of the machining center machine tool is higher than lO000r/min, the centrifugal force generated by the unbalanced amount of the high-speed rotating tool (including the clamping shank) will apply periodic load to the spindle bearing, machine tool components, etc., causing vibration. It will adversely affect spindle bearings, tool life and machining quality. Therefore, high-speed machining imposes strict dynamic balancing requirements on rotating tools. Studying the dynamic balancing technology of high-speed rotating tools and effectively controlling the unbalance of the tools are the necessary prerequisites and supporting technologies for the development and promotion of high-speed cutting technology. The cutting industry in Germany has done a lot of research and development work on high-speed rotary tool balancing technology. This paper introduces the research status of high-speed cutting tool dynamic balance technology and some related issues.
2. Balancing principle of balancing the general concept of <br> <br> rotary tool with rotating parts balancing the general principle is similar. First of all, the design of the tool structure should be as symmetrical as possible. Secondly, when the tool needs to be balanced, the balance can be achieved by using the tool handle to de-weight or adjust the weight according to the measured unbalance. Due to the different types of tools, the specific balancing method is different. The EPB company's special balancing tool (handle) has a balance weight mechanism and a counterweight scale. By rotating the weight ring and adjusting its relative position, it can compensate for the unevenness caused by the asymmetrical structure of the tool or the adjustment of the knife. Measure; Germany's Walter high-speed face milling cutter uses screws to adjust the imbalance.
For a normal tool or tool system, it can be balanced by the tool manufacturer or user with the aid of a balancing machine. However, how to scientifically and quantitatively specify and evaluate the balance quality of the tool and the amount of tool imbalance allowed under different machining conditions is the primary concern of tool manufacturers and users. To this end, it is necessary to introduce the general concept of mechanical rotor dynamic balance.
IS0 1940 "The dynamic balance quality requirements of rigid rotors" standard stipulates that the unbalance amount (or residual unbalance) of a rotor is expressed by U (in gmm), and the U value can be measured on the balance machine; the unevenness allowed by a certain rotor The measure (or allowable residual unbalance) is expressed in Uper. From the viewpoint of the actual balance effect, generally, the larger the mass m (kg) of the rotor, the larger the allowable residual unbalance amount. In order to compare the balance quality of the rotor, it can be expressed by the unit mass residual unbalance amount e, that is, e=U/m (gmm/kg), and accordingly, eper=Uper/m. U and e are the static (or quasi-dynamic) characteristics of the rotor itself for a given rotary axis, which quantifies the degree of imbalance of the rotor. From the perspective of quasi-dynamics, a rotor whose static characteristics are represented by U, e and m values ​​is completely equivalent to an imbalance of mass m (kg) and the eccentricity of its center of gravity and the center of revolution is e (μm). The rotor, and the U value is the product of the rotor mass m (kg) and the eccentricity e (μm). Therefore, e can also be referred to as residual eccentricity, which is a useful physical meaning of e.
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