微喷部件群孔数控电火花加工机床脉冲电源的研究
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摘要
随着先进制造技术的快速发展、制造业市场的竞争激烈化以及世界范围产品的小型化和精密化,产品加工精度的要求也越来越高,微细电火花技术越来越受到各国的重视。在生物技术、生物工程、纺织喷墨印花、金属沉积、微结构制造、电子制造、网络连接、制药、及显示器制造等领域中,精密微喷部件中微细阵列孔的加工精度,成为限制其发展的瓶颈。微细电火花加工技术作为一种非接触的加工方法,具有加工应力小,加工精度高等优点,在微细阵列孔加工中具有很大的优势。
微能脉冲电源作为微细电火花加工机床的重要组成部分,在微细电火花加工中具有重要的位置。本文在阅读大量文献的基础上,分析了以往微细电火花加工电源的特点,发现单一电源模式、能量变化范围较小的微能脉冲电源并不能满足微细阵列孔加工的需求。因此研究一种具有多种加工模式,能量可选范围较大的微能脉冲电源对本课题研究微细阵列孔加工具有重要意义。
本文设计的多模式微能脉冲电源,是一种基于微处理器(MCU)和复杂可编程逻辑器件(CPLD)的主振电路控制,集RC、可控电阻、可控电容等几种放电加工模式于一体的功率放大电路的微能脉冲电源。通过硬件设计、程序编写以及相关调试,完成该微能脉冲电源的制作。在加工过程中,微能脉冲电源可以通过改变电源模式以及开路电压、电阻、电容、占空比等电参数,实现脉冲电源能量在很大范围内可选,确保了脉冲电源能够满足实际加工需求。
然后将调试好的微能脉冲电源运用到试验中,分别对电极磨削以及微细孔加工的电参数进行摸索。分析不同的电参数对加工的影响,选取其中较优的一组参数进行实验验证,实验结果基本与预期分析吻合,说明此微能脉冲电源可实现电极磨削及微细孔加工的目标。
根据前期摸索的电参数规律,分别选择适合电极磨削和微细阵列孔加工的一组电参数,运用到打印机微喷部件阵列孔加工中。在电极磨削加工中发现,此微能脉冲电源能够较理想的加工出直径约为39.5μm,直径偏差在1μm内,长度1050μm,长径比超过26的微细电极轴;在微细阵列孔加工中,能够较稳定的加工直径偏差在2μm之内的2×128阵列孔。
With the rapid development of advanced manufacturing technology, intensification of competition in manufacturing market, and the miniaturization and precision of products worldwide ,requirement of products’precision become more and more higher.and mang countries attach more and more importance to micro EDM.In zhe field of biotechnology, Biological engineering, textile ink-jet printing, metal deposition, microstructure manufacturing, electronics manufacturing, network connection, pharmaceutical and display manufacturing,the precision of micro-arrays holes in accurate micro jet parts,become the restriction of their development. Micro EDM technology as a non-contact processing method, whose processing stress is small, processing precision is high, has a great advantage in the processing of micro-arrays holes.
Micro-energy pulse power as an important component of Micro-EDM machine has an important position in the processing. In this paper, after reading a lot of literature, based on the analysis of the previous Micro EDM power’s characteristics, find that a single power supply mode, and micro-pulse power whose energy range is small can not meet the need of micro-arrays holes processing. Therefore the research of a micro-energy pulse power with multi-mode and a large range of energy options is important in the research of micro-arrays holes processing.
In this paper, design a multi-mode micro-energy pulse power, in which the control of main oscillator circuitis is based on a microprocessor and complex programmable logic device (CPLD), the power amplifier set RC, controlled resistors, controlled capacitors, and other several discharge machining mode in one. Through the design of hardware, programming and related testing, complete the production of micro-energy pulse power supply. In the processing, the micro-energy pulse power can achieve a wide range of optional in energy by , changing the power modes, the open circuit voltage, resistance, capacitance, duty cycle and other electrical parameters, to ensure that the pulse power supply can meet the need of practical processing.
Then apply the micro-energy pulse power debugged to the experiment,and work on the electrical parameters with regard to electrode grinding and micro-hole machining respectively. Afterwards, analyze the effect of diffent electrical parameters on processing,and choose a better set of parameters to verify.The experimental result is consistent with expectation, indicating that the micro-energy pulse power can achieve goals of electrode grinding and micro-hole machining.
According to the preliminary exploration of the law of the electrical parameters, choose a set of electrical parameters suit for electrode grinding and micro-hole machining respectively, and apply them to the processing of array of holes of micro jet parts in printer.In the processing of electrode grinding, find that this micro-energy pulse power can process micro-electrode axises,with its diameter of about 39.5μm, diameter deviation in 1μm, length of 1050μm, aspect ratio of more than 26; and can process 2×128 array of holes with deviation of 2μm in diameter stably in the processing of micro-hole arrays.
微能脉冲电源作为微细电火花加工机床的重要组成部分,在微细电火花加工中具有重要的位置。本文在阅读大量文献的基础上,分析了以往微细电火花加工电源的特点,发现单一电源模式、能量变化范围较小的微能脉冲电源并不能满足微细阵列孔加工的需求。因此研究一种具有多种加工模式,能量可选范围较大的微能脉冲电源对本课题研究微细阵列孔加工具有重要意义。
本文设计的多模式微能脉冲电源,是一种基于微处理器(MCU)和复杂可编程逻辑器件(CPLD)的主振电路控制,集RC、可控电阻、可控电容等几种放电加工模式于一体的功率放大电路的微能脉冲电源。通过硬件设计、程序编写以及相关调试,完成该微能脉冲电源的制作。在加工过程中,微能脉冲电源可以通过改变电源模式以及开路电压、电阻、电容、占空比等电参数,实现脉冲电源能量在很大范围内可选,确保了脉冲电源能够满足实际加工需求。
然后将调试好的微能脉冲电源运用到试验中,分别对电极磨削以及微细孔加工的电参数进行摸索。分析不同的电参数对加工的影响,选取其中较优的一组参数进行实验验证,实验结果基本与预期分析吻合,说明此微能脉冲电源可实现电极磨削及微细孔加工的目标。
根据前期摸索的电参数规律,分别选择适合电极磨削和微细阵列孔加工的一组电参数,运用到打印机微喷部件阵列孔加工中。在电极磨削加工中发现,此微能脉冲电源能够较理想的加工出直径约为39.5μm,直径偏差在1μm内,长度1050μm,长径比超过26的微细电极轴;在微细阵列孔加工中,能够较稳定的加工直径偏差在2μm之内的2×128阵列孔。
With the rapid development of advanced manufacturing technology, intensification of competition in manufacturing market, and the miniaturization and precision of products worldwide ,requirement of products’precision become more and more higher.and mang countries attach more and more importance to micro EDM.In zhe field of biotechnology, Biological engineering, textile ink-jet printing, metal deposition, microstructure manufacturing, electronics manufacturing, network connection, pharmaceutical and display manufacturing,the precision of micro-arrays holes in accurate micro jet parts,become the restriction of their development. Micro EDM technology as a non-contact processing method, whose processing stress is small, processing precision is high, has a great advantage in the processing of micro-arrays holes.
Micro-energy pulse power as an important component of Micro-EDM machine has an important position in the processing. In this paper, after reading a lot of literature, based on the analysis of the previous Micro EDM power’s characteristics, find that a single power supply mode, and micro-pulse power whose energy range is small can not meet the need of micro-arrays holes processing. Therefore the research of a micro-energy pulse power with multi-mode and a large range of energy options is important in the research of micro-arrays holes processing.
In this paper, design a multi-mode micro-energy pulse power, in which the control of main oscillator circuitis is based on a microprocessor and complex programmable logic device (CPLD), the power amplifier set RC, controlled resistors, controlled capacitors, and other several discharge machining mode in one. Through the design of hardware, programming and related testing, complete the production of micro-energy pulse power supply. In the processing, the micro-energy pulse power can achieve a wide range of optional in energy by , changing the power modes, the open circuit voltage, resistance, capacitance, duty cycle and other electrical parameters, to ensure that the pulse power supply can meet the need of practical processing.
Then apply the micro-energy pulse power debugged to the experiment,and work on the electrical parameters with regard to electrode grinding and micro-hole machining respectively. Afterwards, analyze the effect of diffent electrical parameters on processing,and choose a better set of parameters to verify.The experimental result is consistent with expectation, indicating that the micro-energy pulse power can achieve goals of electrode grinding and micro-hole machining.
According to the preliminary exploration of the law of the electrical parameters, choose a set of electrical parameters suit for electrode grinding and micro-hole machining respectively, and apply them to the processing of array of holes of micro jet parts in printer.In the processing of electrode grinding, find that this micro-energy pulse power can process micro-electrode axises,with its diameter of about 39.5μm, diameter deviation in 1μm, length of 1050μm, aspect ratio of more than 26; and can process 2×128 array of holes with deviation of 2μm in diameter stably in the processing of micro-hole arrays.
引文
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[3]王克锡.电火花成型加工机的发展特点和今后的发展[J].电加工,1992(2):42
[4]刘小芹,王军,李望云.微细加工及其关键技术研究[J].工程技术,2007:96
[5] Minoru, Yamazaki, Takemi Suzuki, Noritoshi Mori, Masanori Kunieda. EDM of Micro-rods by Self-drilled Holes Joumal of Materials Processing Technology.2004:134-138
[6]李含林.微喷阵列孔电火花加工多模式脉冲电源系统的研究[D].哈尔滨:哈尔滨工业大学硕士学位论文,2009:10
[7]易茂斌,房丰洲,王庆祎.微细电火花加工装置及加工工艺的研究[J].现代制造工程,2009(3):70
[8] Hull B. The role of elast icity in supp ly chain performance[J]. International Journa lof P roduction Econom ic,s 2005:301-314
[9] S.Webezll.That fisrt step into EDM.Maehiney. Findlay Publieations Ltd,UK,2001:4
[10] Anonymous.Histoyrnaddevelopment,in The Techlliques and Practice of Spark Eorsion Machining,Spacraortn Limited,Gloueester,UK,1965:6.
[11] H.S.Lim,Y.S.Wong,Rahman et al. A Study on the Machining of High-aspect ratio Micro-structures Using Micro-EDM. Journal of Materials Processing Technology,2003,(140):318-32
[12] Heeren Paul-Henri's,Reynaerts Dominiek,Van Brussel Hendrik Micro-structuring of silicon by electro-discharge machining(EDM)-part I:theory Sensors and Actuators,A:Physical 1997,60(5):212 -218
[13]李立青,郭艳玲,白基成,郭永丰.电火花加工技术研究的发展趋势预测[J].机床与液压,2008第36卷(2):174-176
[14] P.Pecas, E.Henriques.In fluence of silicon powder-mixed dielectric on conventional electrical discharge machining[ J ]. Intemational Joumal of M achine Tools & M anufacture,2003,43(11):1465-1471
[15] Y.S.Wong,L.C.Lim,Iqbal Rahuman,et al.Near-m irror-finish phenomenon in EDM using powder-mixed dielectric[J]. Joumal of Materials Processing Technology,1998:30-40
[16] Ken’ichi Takahata, Yogesh B.Gianchandani. Batch Mode Micro-Electro- Discharge Machining [J]. Joumal of Micro electromechanical Systems, 2002 (11) :102– 110
[17] Dong-Yea SHEU, Masuzawa.Development of Large Scale Production of Microholes by EDM [C]. Proceedings of the 13th International Symposium of Electromachining (ISEM),2001(5):747-758
[18] Fuzhu Han, Masanori Kunieda, Hiroaki Hashimo to EDM Using Combined Pulse L ines [J].International Joumal of Machining, JEM , 2001(6) :47-52
[19] Fleischer J , Masuzawa T. New Applications for Micro-EDM. Joumal of Materials ProcessingTechnology[J], 2004 (1) :246-249
[20]宋博岩,赵万生,张宏.绿色电火花加工的概念[J].电加工与模具,2000(6):4-6
[21]高升晖.微细及小孔电火花加工的关键技术研究[D].大连:大连理工大学硕士学位论文,2008:9
[22]贾宝贤,王振龙,赵万生.基于特种加工的微小孔加工技术[J].2005(2):1
[23] Singh A , Gho sh A. A Thermo - elect ric Model of Material Removal during Electric Discharge Machining. International Joumal of Machine Tools &Manufact ure, 1999, 39 (4) :669-682
[24] T.Masuzwa, M.Fujino, K.Kobayashi. Wire Electro-Discharge Grinding for Micro-Machining. Annals of the CIRP[J].1985 (1):431-434
[25] D.Landolt, PF. Chauvy, O.Zinger. Electrochemical micromachining, polishing and surfaces structuring or metals: fundamental aspects and new development [J]. Eletrochinica Acta, 2003(48): 3185-3201.
[26] T. Kawakami, M. Kunieda, Study on Factors Determining Limits of Minimum Machinable Size in Micro EDM[J].CIRP Annals - Manufacturing Technology,2005(54):167-170
[29] Masuzawa T.Three dimensional micro machining by machine tools[D].Annuals ofthe CIRP.1997,46(2):621-628.
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