Papers by Author: Zhen Yuan Jia

Abstract: In modern industry the processing quality and precision become the concerned aspects. The cutting force dynamometer could ensure the two points by adjusting the cutting parameters. A piezoelectric dynamometer is introduced. The electric potential of X0 and Y0 crystal wafer has been analyzed by ANSYS under F_z, F_x and M_z. For the F_x and M_z measurement, the charge distribution expression is calculated by nonlinear elasticity and piezoelectric theory. The dynamometer is designed and the calibration experiments have been had. The nonlinearity and repeatability of M_z, F_x, and F_z are 0.77% and 1.05%, 0.46% and 0.58%, 0.34% and 0.69.

Abstract: The giant magnetostrictive transducer is a prospective kind of transducer for precession position and actuator utilization. The transducer design need cooperated with the mechanics, electrics and magnetics knowledge. It designs the giant magnetostrictive transducer and employed the finite element method to simulate and analysis the transducer’s prestress mechanism and modal analysis, Meanwhile, It uses the Ansoft software simulated and calculated the electrical and magnetical performance of the designed transducer. It presents the calculating method of the actuator’s mechanical, magnetic and thermal system, and utilizes the finite element method to analysis the actuator’s prestress mechanism, modal mode, permanent and electromagnetic magnetic circuit. The simulation results verified the design is reasonable and effective. The discussion of the model, analysis and simulation method of the transducer can direct the future transducer design and manufacture.

Abstract: Based on the analyses of the current research status of PC + NC type control system in micro-machining technical field both at home and abroad, an “IPC + PMAC motion controller” type open CNC system is established. Control circuits of the micro milling machine control system are designed, which include the realization of the functions of spindle status display, feeding tables status display, IPC status display, machine tool alarm, interlocking control of the function buttons and the corresponding indicator light control of spindle cooling, spindle lubrication, spindle alarm and spindle running status. Finally, the safety inspection function of the spindle is achieved through writing corresponding PLC programs. The research of this paper can provide reference for the study of the micro milling machine control system.

Abstract: The fixture of motorized spindle significantly affect the vibration of micro high speed CNC milling machine, its performance can directly affect the machining accuracy of the entire micro milling machine. A special fixture of high-speed motorized spindle is designed in the paper and its static characteristics are checked by utilizing ANSYS finite element analysis software. To guarantee the sufficient strength of bolts and the safety of motorized spindle when the motorized spindle runs at high speed, theory analysis method and ANSYS finite element analysis method are used to make the strength check of the fixture. The designed special fixture for high speed motorized spindle plays an important part in the design of high-speed motorized spindle.

Abstract: The fixture of motorized spindle plays a definitive role in clamping stability and working reliability. If designed irrationally, not only will affect the precision of the micro-milling machines, but also cause the spindle drop. Based on the phenomenon that the spindle drops at high-speed in micro-milling process, this paper optimized the existing fixture, designed the supporting protective device, and analyzed their static characteristics utilizing ANSYS finite element analysis software. To guarantee the sufficient strength of bolts on the fixture and the protective device, both the theory analysis method and ANSYS finite element analysis method are used to make the strength check of the selected bolts. The optimization of the fixture for high speed motorized spindle has far-reaching affect on the design of high-speed motorized spindle.

Abstract: The realization of the handwheel function is a key problem for development of numerical control system of micro milling machine. This paper introduced the interface specifications and hardware connecting methods of handwheel NK100AB2, developed control program based on PMAC (Programmable Multi-Axis Controller) and industrial personal computer, finally achieved the function of axes selecting and the feed rate selecting. Based on the traditional edge detector tool setting method, an improved tool setting method is proposed. The inverted micro milling cutter hilt is used to replace the traditional edge detector, which avoids the opposite reamer error caused by the irregular cutter blade shape, finally, tool setting function is achieved through the collecting of electrical signal. The research will provide a useful reference for the realization of handwheel and tool setting of micro milling machine based on PMAC.

Abstract: The contact between balls and screw races or nut races is a kind of typical non-conformal contact. The study of contact characteristics of ball screw will provide theoretical bases for improving transmission efficiency and working properties of ball screw. In this study, hertz contact theory was adopted to construct the solution formula of ball screw’s contact stiffness, ball screw’s contact characteristics in terms of axial load, design parameters and material properties was analyzed, and the contact deformation value of the contact between ball and screw races was got using finite element simulation method. The simulation result is close to the theoretic value, which proves the correctness of the theory analysis. The present study offers theoretical support for the design and application of high speed, heavy load and precision ball screws.

Abstract: A piezoelectric thrust-measuring platform with high natural frequency is developed for measuring the pulsed thrust generated by attitude-control rocket engines. It consists of two shear mode piezoelectric quartz crystal sensors and an integral shell. The sensors are inserted into the grooves of the elastic rings with an interference fit. Shell stiffness is calculated by energy method (EM) and finite element method (FEM). The shell is optimized for obtaining a good compromise between the sensitivity and frequency response. The stiffness and natural frequency after optimization are verified by experiments. The results show that the stiffness calculated by FEM is more accurate than that calculated by EM. The sensitivity of the thrust-measuring platform is increased by 13.6% compared with before optimization. The natural frequency of the thrust measurement system is 1245 Hz.

Abstract: A design proposal for developing a high-precision timer of the real-time digital copying control system is put forward by analyzing the real-time characteristics of Windows 2000 operating system. Proposals of using information systems timer—WM_TIMER, multimedia timer, VxD and hardware to achieve high-precision timing in Windows operating system are analyzed and compared. Based on computer high-frequency timer and multi-thread technology, timing function provided by Microsoft Visual C++ is used to achieve a high-precision software timer of the system. Finally, the researched timing method is tested in Advantech IPC-610 host with Intel Pentium 4 processor, and the maximum timing error is less than 5μs which meets the system timing requirements.

Abstract: Single crystal MgO can be used as the substrates to deposit HTS films. The subsurface damage (SSD) generated in processing has great effect on the strength and performance of the substrates. However, the characteristics of MgO SSD and its formation mechanism have not been understood fully. In this paper, the surface and subsurface damage caused by saw cutting, rough lapping and fine lapping of MgO substrates were studied by cross-section of microscopy and SEM. The formation mechanism was discussed; and a SSD model was presented.