Research On The Cnc Of The Middle-convex And Varying Piston Processing

The article mainly talks about the middle-convex and varying pisiton's skirt-section NC processing. After introduction of the middle-convex and varying pistion's complex skirt-section, the paper puts forward a new interpolation method: polar coordinate interpolation and speed combining angle interpolation for cross-section; the same precision linear approximation for shaft-section while the article makes a MATLAB stimulation.In order to process the middle-convex and varying pistion's skirt-section, the article developed a prototype of the middle-convex and varying pistion CNC lathe, whose structure of control system is two-computer: upper and lower. The effection of upper computer is to perform the pistion's skirt-section, then using cubic spline function to fit skirt-section surface, at last the upper one tramsmits the NC datas to the lower. The effection of the lower is to drive X,Z axis and principal axis, eventually processing the middle-convex and varying piston's skirt-section.NC system software based on PC hardware platform was developed with windows2000 as a platform, Visual C++ for tool, friendly interface, easy operation, which can input the piston's datas manually, perform NC files post-treatment and so on, basically meets the middle-convex and varying piston CNC processing requirements.High frequency radial feeding unit is the core of the whole machine, which also affects machining precision sharply. The article selected a new kind of linear motor—voice coil linear motor in high frequency feeding nuit, whose magnetic field is sealed, so preventing-magnetic device can be omited.Because its small volume,light weigh,high frequency,high acceleration and so on, so it is especially suitable for reciprocating motion of short trip and high frequency, which can be directly installed on the machine. The article makes a mechanical structure design about high frequency feeding unit, voice coil linear motor equipped tool can be fixed on the machine through linear motor platform, in this way, the structure of machine is compat, easy to operate.