注射机五孔斜排双曲肘合模机构的优化设计
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摘要
本文利用机构学的方法对注射机五孔斜排双曲肘合模机构进行了运动和力学特性分析，系统地建立了运动及力学模型，包括模板行程、油缸行程、行程比、速度变化系数、力的放大倍数、最大启模角、合模力、临界角、系统刚度、合模油缸推力等。并在此基础上对合模力为1000kN的合模机构进行了全面系统的优化设计。
在对肘杆增力机构进行优化设计时，将多目标函数中力的放大倍数作为目标函数，而将其余的目标函数变换为约束条件。采用可自行进行优化的软件MathCAD对肘杆增力机构进行了优化设计，无需自己编制计算程序，只要将原始参数、目标函数及约束条件输入，即可按要求输出结果，省时省力。将优化前后的结果相比较，行程比增加4％，力的放大倍数增加14.5％。
采用ANSYS软件对前、后固定模板及动模板的挠度进行了有限元计算，进而求解了合模机构的系统刚度及临界角。计算中假设：模具为刚体；前、后固定模板在拉杆孔处位移为零；动模板支座处位移为零。计算结果满足技术要求。此外，对合模机构中各构件刚度的合理分配进行了初步探讨。
以往是凭经验通过做图试算的方法来求解合模油缸推力，既不准确又费时费力，若采用解析法也将极其困难。求解合模油缸推力属于一维极值问题，本文采用优化设计中收敛速度较快的黄金分割法来计算合模油缸推力。
无论是中小型注射机还是大型注射机，都要求具有较大的行程比和力的放大倍数，这不仅可以获得最大的模板平均速度，而且可以省力，降低能耗。从优化结果看，优化后的行程比和力的放大倍数都有明显提高，从而提高了合模机构的运动及力学性能，这将使注射机以最低的能耗获得最高的效率。
优化设计方法彻底改变了以往注射机设计中凭经验、考类比以及近似计算等不准确的设计方法，还可将设计人员从繁琐的计算及辅助工作中解放出来，并为注射机的CAD奠定基础。
In this article, an analysis of motional and mechanical characteristics for optimization design for oblique five hinge joint-double toggle clamping unit of injection molding machine is made by structure method, systematically making establishment of motional and mechanical model which includes the mold board stroke, the oil cylinder stroke, ratio of stroke, the speed variation coefficient, the force amplification, the maximum opening angle, the force of clamping, the critical angle, the systematical stiffness, the pushing force of closure oil cylinder and else. Based on above, overall and systematical optimization to clamping unit of which the force of clamping is 1000kN has been produced.
During the optimization design of toggle increasing force unit, magnifying times of foree is regarded as the objective function in all multiple objective functions, other objectives functions are convert into condition of constraints. Adopt MathCAD soft that is able automatically to optimize goals to optimize clamping unit without making program by you. Provided that inputting original parameters, objective function as well as condition of constrains to computer, you will promptly gain results according to your aims. Save your time and energy. Compared with before optimization, outcomes of optimization increase 4% in the ratio of stroke and 14.5% in the force amplification.
Utilize ANSYS to compute deflection of the each of moldboard stroke in infinite elements' method and then solve the systematical stiffness and the critical angle of clamping unit. Make an assumption that mould is rigid body; displacement of front and back mould board is zero in the near of hole of drag link; Displacement of motional mould broad supporting seat is also zero. Outcomes of calculating are source of satisfaction to technical demands. In addition, preliminary investigation is produced to reasonable distribution of structural component stiffness.
In the past, according to experience people find a solution of the force of closure oil cylinder by plotting and test calculating, which is not only inaccurate but also wasting of time
and energy. It is too extremely difficult to solve in analysis. Because solution of foree of closure oil cylinder is one-dimensional problem, the article adopts relatively swift convergence way namely golden section to obtain the force of closure oil cylinder.
Whatever they are medium-scale, small-scale or large-scale injection molding machines, all require larger ratio of stroke and the force amplification, which would not only obtain mould maximum board average velocity but also drop energy consumptions. From optimization results we can get it is obvious that motional and mechanical characteristics has been improved accompanied with ratio of stroke and the force amplification .So we will gain the highest efficiency at a cost of low energy consumptions.
Ways of optimization design completely change previous designing ways which rely on experience, analysis and approximate calculating, emancipate designing people from the hard work and lay a foundation on CAD of injection molding machine.
在对肘杆增力机构进行优化设计时，将多目标函数中力的放大倍数作为目标函数，而将其余的目标函数变换为约束条件。采用可自行进行优化的软件MathCAD对肘杆增力机构进行了优化设计，无需自己编制计算程序，只要将原始参数、目标函数及约束条件输入，即可按要求输出结果，省时省力。将优化前后的结果相比较，行程比增加4％，力的放大倍数增加14.5％。
采用ANSYS软件对前、后固定模板及动模板的挠度进行了有限元计算，进而求解了合模机构的系统刚度及临界角。计算中假设：模具为刚体；前、后固定模板在拉杆孔处位移为零；动模板支座处位移为零。计算结果满足技术要求。此外，对合模机构中各构件刚度的合理分配进行了初步探讨。
以往是凭经验通过做图试算的方法来求解合模油缸推力，既不准确又费时费力，若采用解析法也将极其困难。求解合模油缸推力属于一维极值问题，本文采用优化设计中收敛速度较快的黄金分割法来计算合模油缸推力。
无论是中小型注射机还是大型注射机，都要求具有较大的行程比和力的放大倍数，这不仅可以获得最大的模板平均速度，而且可以省力，降低能耗。从优化结果看，优化后的行程比和力的放大倍数都有明显提高，从而提高了合模机构的运动及力学性能，这将使注射机以最低的能耗获得最高的效率。
优化设计方法彻底改变了以往注射机设计中凭经验、考类比以及近似计算等不准确的设计方法，还可将设计人员从繁琐的计算及辅助工作中解放出来，并为注射机的CAD奠定基础。
In this article, an analysis of motional and mechanical characteristics for optimization design for oblique five hinge joint-double toggle clamping unit of injection molding machine is made by structure method, systematically making establishment of motional and mechanical model which includes the mold board stroke, the oil cylinder stroke, ratio of stroke, the speed variation coefficient, the force amplification, the maximum opening angle, the force of clamping, the critical angle, the systematical stiffness, the pushing force of closure oil cylinder and else. Based on above, overall and systematical optimization to clamping unit of which the force of clamping is 1000kN has been produced.
During the optimization design of toggle increasing force unit, magnifying times of foree is regarded as the objective function in all multiple objective functions, other objectives functions are convert into condition of constraints. Adopt MathCAD soft that is able automatically to optimize goals to optimize clamping unit without making program by you. Provided that inputting original parameters, objective function as well as condition of constrains to computer, you will promptly gain results according to your aims. Save your time and energy. Compared with before optimization, outcomes of optimization increase 4% in the ratio of stroke and 14.5% in the force amplification.
Utilize ANSYS to compute deflection of the each of moldboard stroke in infinite elements' method and then solve the systematical stiffness and the critical angle of clamping unit. Make an assumption that mould is rigid body; displacement of front and back mould board is zero in the near of hole of drag link; Displacement of motional mould broad supporting seat is also zero. Outcomes of calculating are source of satisfaction to technical demands. In addition, preliminary investigation is produced to reasonable distribution of structural component stiffness.
In the past, according to experience people find a solution of the force of closure oil cylinder by plotting and test calculating, which is not only inaccurate but also wasting of time
and energy. It is too extremely difficult to solve in analysis. Because solution of foree of closure oil cylinder is one-dimensional problem, the article adopts relatively swift convergence way namely golden section to obtain the force of closure oil cylinder.
Whatever they are medium-scale, small-scale or large-scale injection molding machines, all require larger ratio of stroke and the force amplification, which would not only obtain mould maximum board average velocity but also drop energy consumptions. From optimization results we can get it is obvious that motional and mechanical characteristics has been improved accompanied with ratio of stroke and the force amplification .So we will gain the highest efficiency at a cost of low energy consumptions.
Ways of optimization design completely change previous designing ways which rely on experience, analysis and approximate calculating, emancipate designing people from the hard work and lay a foundation on CAD of injection molding machine.
引文
[1] 华南工学院．橡胶机械设计．第1版．北京：化学工业出版社，1984．350-460页
[2] 王兴天．注射成型技术．第1版．北京：化学工业出版社，1999．1—28页
[3] 瞿金平．塑料工业手册．第1版．北京：化学工业出版社，2001．1—321页
[4] 北京化工学院．塑料机械设计．第1版．北京：轻工业出版社，1982．318-502页
[5] 饶利滨．浅析我国塑料机械行业的发展方向．中国塑料，1995(4)：10—16
[6] 陈金南．中国塑料机械的生产发展技术现状及前景．中国塑料，1999(2)：1—6
[7] 廖正品．美国2000国家塑料博览会回顾(2)．中国塑料，2000(10)：90—97
[8] 李倩．塑料注射成型技术及其进展．中国塑料，2001(10)：7—13
[9] 王向东，杨惠娣．注射成型技术进展．中国塑料，2001(10)：1-6
[10] 王志新．现代注射机控制．第1版．北京：轻工业出版社，2001，1—22页
[11] 徐敬一．注射螺杆的固体输送理论．塑料科技，1990(1)：35—40
[12] Steller R T. Theoretical Melt for Flow of Polymer Melt in the Screw Channel. Polymer Engineering and Science, 1990(30): 400-412
[13] 王喜顺．注射螺杆的熔体输送理论．中国塑料，2001(1)：73-76
[14] Kamal M R, Patterson W I, Gomes V G. An Injection Molding Study. Polymer Engineering and Science, 1986(2)6:854-866
[15] Osamu Amano, Shirou Utsugi. Temperature Measurement of Polymer Melts in the Heating Barrel During Injection Molding. Part 1. Polymer Engineering and Science, 1988(28): 1565-1576
[16] Osamu Amano, Shirou Utsugi. Temperature Measurement of Polymer Melts in the Heating Barrel During Injection Molding. Part 3. Polymer Engineering and Science, 1990(30): 358-369
[17] Dontula N, Sukanek P C, Devanathan H, Campbell G A. An Experimental and Theoretical Investigation of Transient Melt Temperature During Injection Molding. Polymer Engineering and Science, 1991(31): 1674-1686
[18] Verbraak C P J M, Meijer H E H. Screw Design in Injection Molding. Polymer Engineering Science. 1989(29): 479-492
[19] Kamal M R, Chu E, Lafleur P G. Computer Simulation of Injection Mold Filling forViscoelastic Melts with Fountain Flow. Polymer Engineering Science. 1986(26): 190-203
[20] Mavridis H, Hrymak A N, Vlachopoulos J. Finite Element Simulation of Fountain Flow in Injection Molding. Polymer Engineering Science. 1986(26): 449-452
[21] XiaoShi Jin. Boundary Element Study on Particle Orientation Caused by the Fountain Flow in Injection Molding. Polymer Engineering Science. 1993(19): 1238-1251
[22] Yu J S, Lim M, Kalyon D M. Development of Density Distributions in Injection Molded Amorphous Engineering Plastics. Partl. Polymer Engineering Science. 1991(31): 145-157
[23] Yu J S, Kalyon D M. Development of Density Distributions in Injection Molded Amorphous Engineering Plastics. Part2. Polymer Engineering Science. 1991(31): 158-170
[24] Nguyen K T, Kamal M R. Analysis of the Packing Stage of a Viscoelastic Melt. Polymer Engineering Science. 1993(33): 665-678
[25] Greener J. Pressure-Induced Densification in Injection Molding. Polymer Engineering Science. 1986(26): 534-547
[26] Greener J. General Consequences of the Packing Phase in Injection Molding. Polymer Engineering Science. 1986(26): 886-899
[27] Kamal M R, Lafleur P G. Heat Transfer in Injection Molding of Crystallizable Polymer. Polymer Engineering Science. 1984(24): 692-705
[28] 潘振浩．曲肘式合模机构的优化设计．塑料，1987(5)：24-29
[29] 邱志凌，宣森根．曲肘式合模机构的优化设计．塑料工业，1987(6)：23-27
[30] 陈明，刘兴华．肘杆式合模机构的优化设计．塑料科技，1990(1)：42-47
[31] 丁永红，徐敬一．注射机模板的实用计算模型．塑料科技，1994(2)：42-43
[32] 段绵开，王喜顺，彭玉成．曲肘式合模机构优化设计的研究．中国塑料，1996(4)：63-68
[33] 段绵开．曲肘式合模机构运动特性分析及其优化设计．中国塑料，1996(6)：77-82
[34] 冯良为．注射机双曲肘合模机构的运动和力学特性分析．橡胶工业，1999(9)：546-549
[35] 冯良为．注射成型机五孔斜排合模机构的优化设计．橡胶工业，1999(10)：605-610
[36] 冯良为．注射机模板的可靠性设计设计．特种橡胶制品，2002(1)：48-51
[37] 黄锡恺，郑文纬．机械原理．第5版．北京：人民教育出版社，1981．18-26页
[38] 南京工学院．理论力学，下册．第1版．北京：人民教育出版社，1981．201-225页
[39] 成大先．机械设计手册，第1卷．第四版．北京：化学工业出版社，2002．7-11页
[40] 苏翼林．材料力学，上册．第1版．北京：人民教育出版社，1981．13-14页
[41] 沈守范．MathCAD使用详解．第1版．北京：电子工业出版社，2001．1-68页
[42] 洪庆章．ANSYS教学范例．第1版．北京：中国铁道出版社，2002．1-126页
[43] 潭浩强．QBASIC程序设计教程．第1版．北京：电子工业出版社，2002．1-259页
[44] 机械工业部．塑料注射成型机标准，JB／T7267-94．第1版．1994．1-20页
[45] 汪萍．机械优化设计．第2版．武汉：中国地质大学出版社，1991．163-164页
[2] 王兴天．注射成型技术．第1版．北京：化学工业出版社，1999．1—28页
[3] 瞿金平．塑料工业手册．第1版．北京：化学工业出版社，2001．1—321页
[4] 北京化工学院．塑料机械设计．第1版．北京：轻工业出版社，1982．318-502页
[5] 饶利滨．浅析我国塑料机械行业的发展方向．中国塑料，1995(4)：10—16
[6] 陈金南．中国塑料机械的生产发展技术现状及前景．中国塑料，1999(2)：1—6
[7] 廖正品．美国2000国家塑料博览会回顾(2)．中国塑料，2000(10)：90—97
[8] 李倩．塑料注射成型技术及其进展．中国塑料，2001(10)：7—13
[9] 王向东，杨惠娣．注射成型技术进展．中国塑料，2001(10)：1-6
[10] 王志新．现代注射机控制．第1版．北京：轻工业出版社，2001，1—22页
[11] 徐敬一．注射螺杆的固体输送理论．塑料科技，1990(1)：35—40
[12] Steller R T. Theoretical Melt for Flow of Polymer Melt in the Screw Channel. Polymer Engineering and Science, 1990(30): 400-412
[13] 王喜顺．注射螺杆的熔体输送理论．中国塑料，2001(1)：73-76
[14] Kamal M R, Patterson W I, Gomes V G. An Injection Molding Study. Polymer Engineering and Science, 1986(2)6:854-866
[15] Osamu Amano, Shirou Utsugi. Temperature Measurement of Polymer Melts in the Heating Barrel During Injection Molding. Part 1. Polymer Engineering and Science, 1988(28): 1565-1576
[16] Osamu Amano, Shirou Utsugi. Temperature Measurement of Polymer Melts in the Heating Barrel During Injection Molding. Part 3. Polymer Engineering and Science, 1990(30): 358-369
[17] Dontula N, Sukanek P C, Devanathan H, Campbell G A. An Experimental and Theoretical Investigation of Transient Melt Temperature During Injection Molding. Polymer Engineering and Science, 1991(31): 1674-1686
[18] Verbraak C P J M, Meijer H E H. Screw Design in Injection Molding. Polymer Engineering Science. 1989(29): 479-492
[19] Kamal M R, Chu E, Lafleur P G. Computer Simulation of Injection Mold Filling forViscoelastic Melts with Fountain Flow. Polymer Engineering Science. 1986(26): 190-203
[20] Mavridis H, Hrymak A N, Vlachopoulos J. Finite Element Simulation of Fountain Flow in Injection Molding. Polymer Engineering Science. 1986(26): 449-452
[21] XiaoShi Jin. Boundary Element Study on Particle Orientation Caused by the Fountain Flow in Injection Molding. Polymer Engineering Science. 1993(19): 1238-1251
[22] Yu J S, Lim M, Kalyon D M. Development of Density Distributions in Injection Molded Amorphous Engineering Plastics. Partl. Polymer Engineering Science. 1991(31): 145-157
[23] Yu J S, Kalyon D M. Development of Density Distributions in Injection Molded Amorphous Engineering Plastics. Part2. Polymer Engineering Science. 1991(31): 158-170
[24] Nguyen K T, Kamal M R. Analysis of the Packing Stage of a Viscoelastic Melt. Polymer Engineering Science. 1993(33): 665-678
[25] Greener J. Pressure-Induced Densification in Injection Molding. Polymer Engineering Science. 1986(26): 534-547
[26] Greener J. General Consequences of the Packing Phase in Injection Molding. Polymer Engineering Science. 1986(26): 886-899
[27] Kamal M R, Lafleur P G. Heat Transfer in Injection Molding of Crystallizable Polymer. Polymer Engineering Science. 1984(24): 692-705
[28] 潘振浩．曲肘式合模机构的优化设计．塑料，1987(5)：24-29
[29] 邱志凌，宣森根．曲肘式合模机构的优化设计．塑料工业，1987(6)：23-27
[30] 陈明，刘兴华．肘杆式合模机构的优化设计．塑料科技，1990(1)：42-47
[31] 丁永红，徐敬一．注射机模板的实用计算模型．塑料科技，1994(2)：42-43
[32] 段绵开，王喜顺，彭玉成．曲肘式合模机构优化设计的研究．中国塑料，1996(4)：63-68
[33] 段绵开．曲肘式合模机构运动特性分析及其优化设计．中国塑料，1996(6)：77-82
[34] 冯良为．注射机双曲肘合模机构的运动和力学特性分析．橡胶工业，1999(9)：546-549
[35] 冯良为．注射成型机五孔斜排合模机构的优化设计．橡胶工业，1999(10)：605-610
[36] 冯良为．注射机模板的可靠性设计设计．特种橡胶制品，2002(1)：48-51
[37] 黄锡恺，郑文纬．机械原理．第5版．北京：人民教育出版社，1981．18-26页
[38] 南京工学院．理论力学，下册．第1版．北京：人民教育出版社，1981．201-225页
[39] 成大先．机械设计手册，第1卷．第四版．北京：化学工业出版社，2002．7-11页
[40] 苏翼林．材料力学，上册．第1版．北京：人民教育出版社，1981．13-14页
[41] 沈守范．MathCAD使用详解．第1版．北京：电子工业出版社，2001．1-68页
[42] 洪庆章．ANSYS教学范例．第1版．北京：中国铁道出版社，2002．1-126页
[43] 潭浩强．QBASIC程序设计教程．第1版．北京：电子工业出版社，2002．1-259页
[44] 机械工业部．塑料注射成型机标准，JB／T7267-94．第1版．1994．1-20页
[45] 汪萍．机械优化设计．第2版．武汉：中国地质大学出版社，1991．163-164页