新型齿轮自动消隙机构的研究
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摘要
新型齿轮自动消隙机构是王进戈教授等提出的一项专利技术。它主要用于精密机械传动中双片齿轮之间,改善侧隙存在引起的齿轮传动不稳定,精度不高,可靠性差等问题。与传统的消隙机构相比,其特点和优点在于:新型齿轮自动消隙机构由弹簧,滑块,摆块等三部分组成,结构比较简单;因为滑块有倾角,可使整个结构处于自锁状态,滑块的倾角可调范围大,且不随滑块的位置变化而变化,自锁性好;齿轮承载面与滑块,滑块与摆块,摆块与另一齿轮承载面间均为面接触,承载能力高;该机构不仅适用于平行轴齿轮传动,也适用于蜗轮蜗杆传动,适用范围广。因此它是一种非常实用的消除齿侧间隙的机构。目前对这种自动消隙机构的研究只是提出了原理,作为一种新型传动,我们不仅要设计出它的结构和确定其重要参数,而且需要研究它在工作时的运动和受力,以及进行静动态分析等。
本文所做的研究工作主要包括:
1根据新型齿轮自动消隙机构的工作原理,对机构进行必要的运动和受力分析,为后面结构的设计以及有限元分析提供了条件。
2用MATLAB优化工具箱,对运动和受力方程进行优化处理,得到新型齿轮自动消隙机构中主要构件如滑块,摆块的尺寸参数;根据设计出的滑块和摆块的尺寸,以及配合的齿轮参数,结合机械设计知识,设计弹簧。
3用Pro/E三维建模软件建立新型齿轮副和新型蜗轮副的三维模型;运用Pro/E下的机构模块,对新型齿轮副进行动态仿真,验证了有无干涉,分别在滑块与齿轮,滑块与摆块,齿轮与摆块结合面上选取一点,得出这三个点的位移,速度及加速度曲线。
4将在Pro/E中建立的自动消隙机构和蜗轮副模型分别导入ANSYS中,对新型齿轮自动消隙机构进行应力分析,得到自动消隙机构应力分布图;对蜗轮副进行模态分析,得到蜗轮副十阶模态频率值以及振型图。
The new-typed auto-eliminate backlash mechanism is a patent developed by Professor Wang Jinge, It is used between two gears in exact mechanical drive, in order to eliminate instability ,low precision, poor reliability of the gear drive, which are derived from the backlash. Compared with the traditional eliminate backlash mechanism, the characteristic and the excellence of the new-typed auto-eliminate backlash mechanism are as the follows: The new-typed auto-eliminate backlash mechanism consists of spring, slider and pendulum, then the structure is simpleness. Slider has obliquity to ensure that the whole machinery remain in self locking, the adjustable scope of slider’obliquity is great, and it does not vary with location of slider, therefore, the self locking is good. Contacts between gear and slider, slider and pendulum, another gear and pendulum are by areas, then carrying capacity is high. The new-typed auto-eliminate backlash mechanism uses to not the parallel axial gear but the worm and gear, so the suitable scope is wide. According to these reasons, the new-typed auto-eliminate backlash mechanism is applied. At the present time, the research about the new-typed auto-eliminate backlash mechanism have been done to advance the principle, as a new-typed drive, the structure and the important parameters should be designed, the movement and the force should be studied, meanwhile, the static and the dynamic should be analysed.
The research of this article is as follows:
1 Based on the principle of the new-typed auto-eliminate backlash mechanism, the essential movement and force of the mechanism are analysed , which offers the condition to the design of the structure and finite element analysis.
2 After the equations of the movement and the force are optimized by the optimize toolbox of MATLAB, the dimension parameters of slider and pendulum, which are the important component of the new-typed auto-eliminate backlash mechanism, are obtained. Based on the designed dimensions of slider and pendulum and the parameter of the coordinate gear, combining the mechanism design, the spring is designed.
3 3D-model of the new-typed gear pair and the new-typed worm pair are established by Pro/E, the dynamic imitation is finished by the mechanic module of Pro/E, interference is validated, a point is chose on the combine area between slider and gear, slider and pendulum, another gear and the pendulum separately, the drawing of the displacements, velocities and accelerations of the three points are gotten.
4 Auto-eliminate backlash mechanism and worm pair, established by Pro/E, are lead to ANSYS, then the analysis of contact stress of auto-eliminate backlash mechanism is finished and the stress distribution map is obtained ; the analysis of model of worm pair is finished and ten step frequencies and model patterns are gotten.
本文所做的研究工作主要包括:
1根据新型齿轮自动消隙机构的工作原理,对机构进行必要的运动和受力分析,为后面结构的设计以及有限元分析提供了条件。
2用MATLAB优化工具箱,对运动和受力方程进行优化处理,得到新型齿轮自动消隙机构中主要构件如滑块,摆块的尺寸参数;根据设计出的滑块和摆块的尺寸,以及配合的齿轮参数,结合机械设计知识,设计弹簧。
3用Pro/E三维建模软件建立新型齿轮副和新型蜗轮副的三维模型;运用Pro/E下的机构模块,对新型齿轮副进行动态仿真,验证了有无干涉,分别在滑块与齿轮,滑块与摆块,齿轮与摆块结合面上选取一点,得出这三个点的位移,速度及加速度曲线。
4将在Pro/E中建立的自动消隙机构和蜗轮副模型分别导入ANSYS中,对新型齿轮自动消隙机构进行应力分析,得到自动消隙机构应力分布图;对蜗轮副进行模态分析,得到蜗轮副十阶模态频率值以及振型图。
The new-typed auto-eliminate backlash mechanism is a patent developed by Professor Wang Jinge, It is used between two gears in exact mechanical drive, in order to eliminate instability ,low precision, poor reliability of the gear drive, which are derived from the backlash. Compared with the traditional eliminate backlash mechanism, the characteristic and the excellence of the new-typed auto-eliminate backlash mechanism are as the follows: The new-typed auto-eliminate backlash mechanism consists of spring, slider and pendulum, then the structure is simpleness. Slider has obliquity to ensure that the whole machinery remain in self locking, the adjustable scope of slider’obliquity is great, and it does not vary with location of slider, therefore, the self locking is good. Contacts between gear and slider, slider and pendulum, another gear and pendulum are by areas, then carrying capacity is high. The new-typed auto-eliminate backlash mechanism uses to not the parallel axial gear but the worm and gear, so the suitable scope is wide. According to these reasons, the new-typed auto-eliminate backlash mechanism is applied. At the present time, the research about the new-typed auto-eliminate backlash mechanism have been done to advance the principle, as a new-typed drive, the structure and the important parameters should be designed, the movement and the force should be studied, meanwhile, the static and the dynamic should be analysed.
The research of this article is as follows:
1 Based on the principle of the new-typed auto-eliminate backlash mechanism, the essential movement and force of the mechanism are analysed , which offers the condition to the design of the structure and finite element analysis.
2 After the equations of the movement and the force are optimized by the optimize toolbox of MATLAB, the dimension parameters of slider and pendulum, which are the important component of the new-typed auto-eliminate backlash mechanism, are obtained. Based on the designed dimensions of slider and pendulum and the parameter of the coordinate gear, combining the mechanism design, the spring is designed.
3 3D-model of the new-typed gear pair and the new-typed worm pair are established by Pro/E, the dynamic imitation is finished by the mechanic module of Pro/E, interference is validated, a point is chose on the combine area between slider and gear, slider and pendulum, another gear and the pendulum separately, the drawing of the displacements, velocities and accelerations of the three points are gotten.
4 Auto-eliminate backlash mechanism and worm pair, established by Pro/E, are lead to ANSYS, then the analysis of contact stress of auto-eliminate backlash mechanism is finished and the stress distribution map is obtained ; the analysis of model of worm pair is finished and ten step frequencies and model patterns are gotten.
引文
[1]陈瑜.机电一体化产品设计指南[M].北京:机械工业出版社,2000.
[2]张建民.机电一体化原理与应用[M].北京:国防工业出版社,1992.
[3]郑堤,唐可洪.机电一体化设计基础[M].北京:机械工业出版社,1997.
[4]会田俊夫,齿轮的糟度与性能(第一版)[M],北京:中国农业机械出版牡,1985.
[5] Winter H, et a1。Investigation on the excitation of vibration and noise at spur and helical gears.proc. of 1989 ASME International Power Transmi8sion&Gearing conference[C],chicago,April,1989.
[6] Smith D J.Gears and their vibration.Marcel Dekker,New York,1983.
[7] Munro R G.The dynamic behavior of spur gears.PhD Thesis,Cambridge University,1962.
[8] Seireg A and Houser D R,Evaluation of dynamic factors for spur and helical gears. ASME Journal of Engineering for Industry,1970.
[9] Tobe T and Kato M.Dynamic loads on spur gear teeth caused by teeth impact.Bulletin of JSME,1973,16(96):103l-1037.
[10]吴江。无侧隙双滚柱包络环面蜗杆传动的设计与制造[D].成都,西华大学,2009.
[11]朱孝录,鄂中凯.齿轮承载能力分析。北京:高等教育出版社,1992.
[12]李勇,李伟光,等。机械设备数控技术[M].北京:国防工业出版社,2007.
[13]伍利群。齿轮传动间隙的消除方法[J].机床与液压,2005(5):187-188.
[14]郭聚东,彭伟,等。精密齿轮传动中齿轮副侧隙的调整方法[J].起重运输机械,2005(2):80-81.
[15]邱新桥,陈建国,等。圆柱齿轮侧隙间隙自动补偿新方法的研究[J]。机械传动,2003(4):49-50.
[16] Lin H H,wang J,et a1.Effect of extended tooth contact on the modeling of spur gear transmissions。Gear Technology,1994(7/8):18-25.
[17]王跃宏,曲波,周辉,等.数控回转台进给系统的消隙机构[J].机械工程师, 2003, 8: 90-91.
[18]邱金林。一种简单轴向弹性错齿消隙法,杭州机械,2000-2,17-20.
[19]邱新桥。一种齿轮齿侧间隙自动补偿机构:中国,02284069.9[P].2002,11,02.
[20]王进戈。滚锥包络环面蜗杆传动[M].成都:四川科学技术出版社,新疆科技卫生出版社(K),2000.
[21]洪雷。无侧隙双滚子包络环面蜗杆传动的理论研究[D].成都,西华大学,2008.
[22]邓星桥,王进戈,张均富,等。无侧隙双滚子包络环面蜗杆真实啮合齿面的理论研究[J].西南交通大学学报,2010(4):222-226.
[23]孙桓,陈作模主编.机械原理(第五版)。北京:高等教育出版社,1995.
[24]赵松平,佟杰新.现代设计方法[M].北京:机械工业出版社.1996.169-179.
[25]郭仁生.基于MATLAB和Pro/ENGINEER优化设计实例解析[M].北京:机械工业出版社.
[26]林成森。数值计算方法。北京:科学出版社[M],2004.
[27]郑阿奇,曹弋,等,MATLAB使用教程[M]。北京:电子工业出版社,2008.
[28]尚涛石,端伟,安宁.工程计算可视化与MATLAB实现[M].武汉:武汉大学出版社, 2002.
[29]郭仁生.机械工程设计分析和MATLAB应用[M]。北京:机械工业出版社.
[30]丁庆新,孙广斌,等。三偏心蝶阀优化设计的遗传算法及Matlab实现[J].石油机械,2009(11):22-24.
[31]周智峰,张明.基于MATLAB的最优化问题求解通用程序的实现[J].机械传动,2004(6):28-32.
[32]王宏立,张祖立,白晓虎,等.基于MATLAB的膨化机结构工艺参数的最优化设计[J].食品与机械,2003(4):28-29.
[33]刘鲭洁,陈桂明,杨旗,等.基于Matlab工具的遗传算法求解有约束最优化问题[J].兵工自动化,2008(11):43-44.
[34]陈飞婷.基于遗传算法的变架机构的设计[D].武汉:武汉理工大学,2004.
[35]王富民,张扬,田社平,等.遗传算法与惩罚函数法在机械优化设计中的应用[J].中国计量学院学报,2004(4):290-293.
[36]李汉兴,靛麦红,眭满仓.基于遗传算法的石油机械优化设计[J].石油机械,1999,27(3):10-12.
[37]成大先.机械设计手册第3卷[M].化学工业出版社.2002.
[38]齿轮手册编委会.齿轮手册(上).北京:机械工业出版社,1990.
[39]濮良贵,季名刚,等。机械设计[M].北京:高等教育出版社,2006.
[40]韩玉龙.Pro/ENGINEER Wildfire 3.0装配与产品设计教程[M].北京:清华大学出版社.
[41]胡人喜,张心俊,吴高阳,等.Pro/ENGINEER Wildfire 3.0中文版机械设计高级应用实例[M].北京:机械工业出版社.
[42]方建军,刘仕良,等.机械动态仿真与工程分析—Pro/ENGINEER Wildfire工程应用.北京:化学工业出版社,工业装备与信息工程出版中心,2004.
[43]和青芳,徐征,等.Pro/ENGINEER Wildfire产品设计与机构动力学分析[M].北京:机械工业出版社,2004.
[44]洪雷,无侧隙双滚子包络环面蜗杆传动的啮合分析,成都:西华大学学报(自然科学版) 2008,27(03):18-23.
[45]张继春,杨建国,等.装配设计与运动仿真及Pro/E实现[M].北京:国防工业出版社,2006.
[46]林清安.Pro/ENGINEER零件设计进阶篇(上)Wildfire[M].北京:中国铁道出版社,2004.
[47]祝凌云,李斌,等.Pro/ENGINEER运动仿真和有限元分析[M].北京:人民邮电出版社,2004.
[48]王雷。Pro/ENGINEER(野火版)应用基础与产品造型实例[M],北京:人民邮电出版社,2003.
[49]马志武.应用于ATC装置的新型组合凸轮机构设计与运动仿真[D].大连:大连轻工业学院,2007.
[50]王国强.实用工程数值模拟技术及其在ANSYS上的实践[M].西北工业大学出版社,2001.
[51]邵蕴秋.ANSYS 8.0有限元分析实例导航[M].北京:中国铁道出版社,2004.
[52]尚晓江,邱峰,赵海峰,李文颖,等.ANSYS结构有限元高级分析方法与范例应用[M].北京:中国水利水电出版社,2005.
[53]商跃进等.有限元原理ANSYS应用指南[M].北京:清华大学出版社,2005.
[54]朱伯芳.有限单元法原理和应用[M].北京:水利电力出版社,1979.
[55]孙菊芳,荣王伍.有限单元法及其应用[M].北京:北京航空航天大学出版社,1996.
[56]吴鸿庆.结构有限元分析[M].北京:中国铁道出版社,2000.
[57]李景涌.有限元法[M].北京:北京邮电大学出版社,1998.
[58]周传月.工程有限元与优化分析应用实例教程[M].北京:科学出版社,2001.
[59]邓凡平.ANSYS10.0有限元分析自学手册[M].北京:人民邮电出版社,2007.
[60]武思宇,罗伟,等.ANSYS工程计算应用教程[M].北京:中国铁道出版社,2004.
[61]龙慧,张光辉等.渐开线直齿轮n齿合过程中载荷及应力的计算机模拟.机械工程学报,1995,31(5):39-44.
[62]李润方,王建军,等。齿轮系统动力学[M].北京:科学出版社,1997.
[63]陈立平,张云清,任卫群,覃刚,等.机械系统动力学分析及ADAMS应用教程[M].北京:清华大学出版社,2005.
[64] Richardson H H.Static and dynamic load, stress , and deflection cycies in spur gear systems.ScD Thesis,ScD Thesis, M.I.T.,1958.
[65] Harris S L.Dynamic loads on the teeth of spur gears.Proceedings of the Institute of Mechanical Engineers,1958,172:180-187.
[66]叶友东,周哲波,等.基于ANSYS直齿圆柱齿轮有限元模态分析.2006(5):63-65.
[67] 6 Kasuba R and Evans J W.An extended model for determing dynamic loads in spur gearing.ASME Journal of Mechanical Design,1981,20:398-409.
[68] Cornell R W and Westerrelt W w.Dynamic tooth loads and stressing for high contact ratio spur gears.ASME Journal of Mechanical Design,1978,100:69-77.
[69]曹树谦、张文德、萧龙翔.振动结构模态分析理论、试验与应用[M].天津:天津大学出版,2001.3.
[70]王红香.非正交面齿轮传动的动力学分析[D].南京:南京航空航天大学,2009.
[2]张建民.机电一体化原理与应用[M].北京:国防工业出版社,1992.
[3]郑堤,唐可洪.机电一体化设计基础[M].北京:机械工业出版社,1997.
[4]会田俊夫,齿轮的糟度与性能(第一版)[M],北京:中国农业机械出版牡,1985.
[5] Winter H, et a1。Investigation on the excitation of vibration and noise at spur and helical gears.proc. of 1989 ASME International Power Transmi8sion&Gearing conference[C],chicago,April,1989.
[6] Smith D J.Gears and their vibration.Marcel Dekker,New York,1983.
[7] Munro R G.The dynamic behavior of spur gears.PhD Thesis,Cambridge University,1962.
[8] Seireg A and Houser D R,Evaluation of dynamic factors for spur and helical gears. ASME Journal of Engineering for Industry,1970.
[9] Tobe T and Kato M.Dynamic loads on spur gear teeth caused by teeth impact.Bulletin of JSME,1973,16(96):103l-1037.
[10]吴江。无侧隙双滚柱包络环面蜗杆传动的设计与制造[D].成都,西华大学,2009.
[11]朱孝录,鄂中凯.齿轮承载能力分析。北京:高等教育出版社,1992.
[12]李勇,李伟光,等。机械设备数控技术[M].北京:国防工业出版社,2007.
[13]伍利群。齿轮传动间隙的消除方法[J].机床与液压,2005(5):187-188.
[14]郭聚东,彭伟,等。精密齿轮传动中齿轮副侧隙的调整方法[J].起重运输机械,2005(2):80-81.
[15]邱新桥,陈建国,等。圆柱齿轮侧隙间隙自动补偿新方法的研究[J]。机械传动,2003(4):49-50.
[16] Lin H H,wang J,et a1.Effect of extended tooth contact on the modeling of spur gear transmissions。Gear Technology,1994(7/8):18-25.
[17]王跃宏,曲波,周辉,等.数控回转台进给系统的消隙机构[J].机械工程师, 2003, 8: 90-91.
[18]邱金林。一种简单轴向弹性错齿消隙法,杭州机械,2000-2,17-20.
[19]邱新桥。一种齿轮齿侧间隙自动补偿机构:中国,02284069.9[P].2002,11,02.
[20]王进戈。滚锥包络环面蜗杆传动[M].成都:四川科学技术出版社,新疆科技卫生出版社(K),2000.
[21]洪雷。无侧隙双滚子包络环面蜗杆传动的理论研究[D].成都,西华大学,2008.
[22]邓星桥,王进戈,张均富,等。无侧隙双滚子包络环面蜗杆真实啮合齿面的理论研究[J].西南交通大学学报,2010(4):222-226.
[23]孙桓,陈作模主编.机械原理(第五版)。北京:高等教育出版社,1995.
[24]赵松平,佟杰新.现代设计方法[M].北京:机械工业出版社.1996.169-179.
[25]郭仁生.基于MATLAB和Pro/ENGINEER优化设计实例解析[M].北京:机械工业出版社.
[26]林成森。数值计算方法。北京:科学出版社[M],2004.
[27]郑阿奇,曹弋,等,MATLAB使用教程[M]。北京:电子工业出版社,2008.
[28]尚涛石,端伟,安宁.工程计算可视化与MATLAB实现[M].武汉:武汉大学出版社, 2002.
[29]郭仁生.机械工程设计分析和MATLAB应用[M]。北京:机械工业出版社.
[30]丁庆新,孙广斌,等。三偏心蝶阀优化设计的遗传算法及Matlab实现[J].石油机械,2009(11):22-24.
[31]周智峰,张明.基于MATLAB的最优化问题求解通用程序的实现[J].机械传动,2004(6):28-32.
[32]王宏立,张祖立,白晓虎,等.基于MATLAB的膨化机结构工艺参数的最优化设计[J].食品与机械,2003(4):28-29.
[33]刘鲭洁,陈桂明,杨旗,等.基于Matlab工具的遗传算法求解有约束最优化问题[J].兵工自动化,2008(11):43-44.
[34]陈飞婷.基于遗传算法的变架机构的设计[D].武汉:武汉理工大学,2004.
[35]王富民,张扬,田社平,等.遗传算法与惩罚函数法在机械优化设计中的应用[J].中国计量学院学报,2004(4):290-293.
[36]李汉兴,靛麦红,眭满仓.基于遗传算法的石油机械优化设计[J].石油机械,1999,27(3):10-12.
[37]成大先.机械设计手册第3卷[M].化学工业出版社.2002.
[38]齿轮手册编委会.齿轮手册(上).北京:机械工业出版社,1990.
[39]濮良贵,季名刚,等。机械设计[M].北京:高等教育出版社,2006.
[40]韩玉龙.Pro/ENGINEER Wildfire 3.0装配与产品设计教程[M].北京:清华大学出版社.
[41]胡人喜,张心俊,吴高阳,等.Pro/ENGINEER Wildfire 3.0中文版机械设计高级应用实例[M].北京:机械工业出版社.
[42]方建军,刘仕良,等.机械动态仿真与工程分析—Pro/ENGINEER Wildfire工程应用.北京:化学工业出版社,工业装备与信息工程出版中心,2004.
[43]和青芳,徐征,等.Pro/ENGINEER Wildfire产品设计与机构动力学分析[M].北京:机械工业出版社,2004.
[44]洪雷,无侧隙双滚子包络环面蜗杆传动的啮合分析,成都:西华大学学报(自然科学版) 2008,27(03):18-23.
[45]张继春,杨建国,等.装配设计与运动仿真及Pro/E实现[M].北京:国防工业出版社,2006.
[46]林清安.Pro/ENGINEER零件设计进阶篇(上)Wildfire[M].北京:中国铁道出版社,2004.
[47]祝凌云,李斌,等.Pro/ENGINEER运动仿真和有限元分析[M].北京:人民邮电出版社,2004.
[48]王雷。Pro/ENGINEER(野火版)应用基础与产品造型实例[M],北京:人民邮电出版社,2003.
[49]马志武.应用于ATC装置的新型组合凸轮机构设计与运动仿真[D].大连:大连轻工业学院,2007.
[50]王国强.实用工程数值模拟技术及其在ANSYS上的实践[M].西北工业大学出版社,2001.
[51]邵蕴秋.ANSYS 8.0有限元分析实例导航[M].北京:中国铁道出版社,2004.
[52]尚晓江,邱峰,赵海峰,李文颖,等.ANSYS结构有限元高级分析方法与范例应用[M].北京:中国水利水电出版社,2005.
[53]商跃进等.有限元原理ANSYS应用指南[M].北京:清华大学出版社,2005.
[54]朱伯芳.有限单元法原理和应用[M].北京:水利电力出版社,1979.
[55]孙菊芳,荣王伍.有限单元法及其应用[M].北京:北京航空航天大学出版社,1996.
[56]吴鸿庆.结构有限元分析[M].北京:中国铁道出版社,2000.
[57]李景涌.有限元法[M].北京:北京邮电大学出版社,1998.
[58]周传月.工程有限元与优化分析应用实例教程[M].北京:科学出版社,2001.
[59]邓凡平.ANSYS10.0有限元分析自学手册[M].北京:人民邮电出版社,2007.
[60]武思宇,罗伟,等.ANSYS工程计算应用教程[M].北京:中国铁道出版社,2004.
[61]龙慧,张光辉等.渐开线直齿轮n齿合过程中载荷及应力的计算机模拟.机械工程学报,1995,31(5):39-44.
[62]李润方,王建军,等。齿轮系统动力学[M].北京:科学出版社,1997.
[63]陈立平,张云清,任卫群,覃刚,等.机械系统动力学分析及ADAMS应用教程[M].北京:清华大学出版社,2005.
[64] Richardson H H.Static and dynamic load, stress , and deflection cycies in spur gear systems.ScD Thesis,ScD Thesis, M.I.T.,1958.
[65] Harris S L.Dynamic loads on the teeth of spur gears.Proceedings of the Institute of Mechanical Engineers,1958,172:180-187.
[66]叶友东,周哲波,等.基于ANSYS直齿圆柱齿轮有限元模态分析.2006(5):63-65.
[67] 6 Kasuba R and Evans J W.An extended model for determing dynamic loads in spur gearing.ASME Journal of Mechanical Design,1981,20:398-409.
[68] Cornell R W and Westerrelt W w.Dynamic tooth loads and stressing for high contact ratio spur gears.ASME Journal of Mechanical Design,1978,100:69-77.
[69]曹树谦、张文德、萧龙翔.振动结构模态分析理论、试验与应用[M].天津:天津大学出版,2001.3.
[70]王红香.非正交面齿轮传动的动力学分析[D].南京:南京航空航天大学,2009.