Research And Design Of CAD/CAM Technology On Cylinder-cone Surface Planing By Double Housing Planer

The difficulty of cylinder-cone surface processing urgently solved by machinery manufacturing industry,the cylinder-cone core will replace the column core currently applied to concrete forming machine in order to improve the performance and quality of the concrete precast panel,conforming to the low-carbon economic policies of our country.With the decided advantage of CAM technology in modern automated manufacturing,an increasing number of enterprises have been trying to explore the better ways to combine existing processing equipments with CAM technology to improve the utilization of existing equipments and resolve the difficulty of some works processing.The cylinder-cone core isn't widely applied to concrete forming machine because of the difficulty of it's processing in ordinary processing machines.Therefore,based on the solution to interpolation method for planning the cross-section on CNC planner,the shaping method of cylinder-cone surface and the control method of shaping are researched by CAD.The planer was applied into the cylinder-cone surface processing,with the single coordinate interpolation using optical grating displacement sensor installed parallel with part axis as the third interpolation coordinate.The core can be processed by the coordinated motion between the existing two-dimensional machining axis in planer and the third axis.The tool path is simulated by CAD to plane the cylinder-cone core and differences between the planing model and the ideal model are analyzed.The stress and strain contacting between the different two concrete precast panel generated by the two model and the column core are analyzed by ANSYS.In the current processing condition,it is economical and practical feasible to plane the cylinder-cone core by the planer.Based on the three elements of the cylinder-cone core and the characteristics of planer planing,the designed CNC system of planer contains two separate systems.The cylinder-cone surface core is shaped by the coordinated motion between the bus controlled by PC system and the led controlled by MCU.To ensuring the stability of the whole system,the tool is only controlled by either system in each processing phase,because the electromagnetic sensor signals are attained for the operation of two systems.According to CNC theory and the experience of numerical control reconstruction,the feed servo system of CAM is completed based on the existing ordinary hardware of the planer:the transformation of both horizontal and vertical axes of CNC tool holder's is designed by the scheme of open loop control system;The grating scale signal is detected by means of 80C52,which has strong ability to accept interruption and count and control the state of stepper motor;The signal of tool feeding status provided for NC system is obtained by electromagnetic sensor installed on the bench.Through analyzing the surface shaping method of cylinder-cone surface and gouging characteristics of the planer studied,a "PC+PCI-1750" CNC system structure is designed by the scheme of open CNC controller based on personal computer,which completes the led by the two-dimensional interpolation of the cross-section curves.The planer CNC system is developed by multi-threading technology provided by VC++ 6.0 and the way of external interrupt provided by PCI-1750 to realize a variety of tasks,such as program operation,the processing path simulation,automatic processing,serial communication,and attain the signals of sensors.Interpolation calculation thread,signal detection thread,processing thread and simulation thread are created.The single coordinate interpolation is completed by the MCU applied to track the workbench,to achieve the bus forming the cylinder-cone surface.To obtain good results in controlling the process by MCU and improve the reliability of the system,the reasonable arrangements of tasks in MCU are designed,the external circuit of obtain signals designed as well.And the serial communication module is designed for setting the internal parameters in MCU,to control the taper and the position of cone.To ensure the continuity of section interpolation,the position of tool is restored to the position of section interpolation at the end of the single coordinate interpolation.