The Identificaiton Research And Application Of High-speed Double-side Locking Toolholder-spindle Joint

The high-speed processing is one of the high-tech manufacturing techniques inrecent years. High-speed machining can significantly improve processing efficiency,reduce the cutting force and cutting temperature, improve tool life and workpiecesurface quality. The toolholder is the important portion which connected to the spindleand tool of CNC machines tools, and affects the machining accuracy, efficiency andtool life directly. The research about toolholder-spindle system is highly concerned byscholars. The high-speed double-sided locking BT (BTF) toolholder is one of the newtoolholder for high-speed processing. The scholars carry out the structure andperformance research of the BTF toolholder-spindle system which has importanttheoretical significance and broad prospect of engineering application.The thesis takes BTF type toolholder as an example. The main contents of thethesis include:(1) By comparative with BT type and HSK type toolholder, the structurecharacteristics of BTF type toolholder is analyzed deeply. The thesis reveals thesuperiority of the BTF toolholder for high speed processing and introduces the mainproperties and applications, which provide theoretical basis for the promotion.(2) The thesis introduces the Euler-Bernoulli beam element modeling method andthe Timoshenko beam element modeling method of mechanical system. The dynamicmodel of the toolholder and spindle are establishes by using Euler-Bernoulli beam andTimoshenko beam element, respectively. We get the frequency response function oftoolholder and spindle, and compare with the experimental data. The researchprovides theoretical basis for parameter identification of the toolholder-spindle joint.(3) The thesis presents the identification approach of dynamic contactparameters for toolholder-spindle joint base on frequency response function. Usingthe method, we can get the joint parameters curve of the BTF40typetoolholder-spindle experimental setup, and get the parameter values by sensitivityanalysis. Matrix27unit is used to verify the validity of the method. The influence ofdifferent drawbar force on the parameters of toolholder-spindle joint is alsointroduced.(4) Finally, the BT40type and BTF40type toolholder-spindle dynamic contactparameters based on the machine tool is identified, respectively. The cutting test is carried out under the same cutting parameters. It verifies the validity of theidentification method according to the workpiece surface quality. It can provide atheoretical basis for the prediction of cutting stability and toolholder structureoptimization.