捏合块数控磨床的关键技术研究
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摘要
捏合块是同向双螺杆挤出机中广泛使用着一种螺杆元件,其外形较复杂,精度要求较高。目前我国的捏合块制造工艺还相对落后,捏合块轮廓曲线加工精度无法保证,大大影响了挤出机的整机性能。因而,对捏合块的磨削成形机理进行研究,解决捏合块数控磨床研制的关键技术问题,研制出先进高效的数控捏合块磨床,无疑将促进我国的双螺杆挤出机制造工艺水平的提高。
捏合块磨削时,由于其形状的特殊性,若零件以匀角速度旋转,则捏合块轮廓面各磨削点的线速度、磨削力等都不一样,这将严重影响磨削质量,如产生波纹、烧伤和形状误差等。针对国内现有加工工艺的不足,我们提出了挤出机捏合块等线速磨削的工艺方法。在对捏合块进行结构分析的基础上,以单位时间内等弧长进行磨削,建立捏合块等线速磨削的数学模型,计算砂轮中心的运动轨迹,自动生成NC数控指令,经实际磨削试验,取得了较好的磨削效果。
本论文在扬州大学机电研究所帮助支持下,在外圆磨床基础上改造了一台捏合块数控磨床,根据捏合块磨削所需的运动对外圆磨床的床身、磨头和头架进行了改造,设计了砂轮修整装置,满足了捏合块磨床的精度、刚性和结构合理性要求。
所改造的捏合块数控磨床控制系统是以PMAC伺服运动控制器为基础,采用“PMAC+PC”的结构形式研制和开发了专用磨床数控系统,将系统开发平台直接构建于PC微机基础之上,实现软硬件功能模块化,各功能模块之间通过标准的接口协调工作,共同完成捏合块磨削所需的数控功能。所研制的系统具有程序译码解释、插补计算、伺服控制、系统管理等控制功能,它不仅具备了一般商用数控系统所要求的通用功能,而且还具备了捏合块磨床所必需的参数输入、砂轮修整轨迹计算、捏合块磨削和砂轮修整程序自动生成等特定功能。同时,系统还为用户设置了今后根据需求增减的模块。
本论文通过捏合块磨削工艺试验,获取了实用可行的捏合块磨削参数。并对磨削参数进行了优化,使捏合块磨削具有较高的磨削效率和质量。
Kneading blocks are a kind of screw elements wildly used in co-rotating twin screw extruders, with complicated shape and high precision. At present, it’s lag in technology for kneading block manufacturing, or say, the outline precision of kneading block can not be ensured, which influences the whole property of extruders greatly. Therefore, studying the mechanism of grinding process, resolving the key problems of developing NC grinding machine and developing advanced and effective machine will improve our country manufacture technology level of twin screw extruder undoubtedly.
If part rotates at a constant angular velocity during grinding process for its special shape, the linear velocity and grinding force of each grinding point on kneading block profile is different, which influences the grinding quality terribly, resulting in wave, burn and shape errors occurrence. In order to make up the defect of present manufacturing technology, we bought forward the new technology of equal linear velocity grinding. Based on kneading blocks' structure analysis, making the machine grind with equal arc length per unit time, we built up the mathematical model of the equal linear velocity grinding. During the manufacturing process, numerical control instruction can be produced and the trajectory of wheel center can be calculated automatically. Modified by real grinding experiments, the grinding effective is very good.
Kneading block NC grinding machines have already been succeeded developing by the mechano-electronic study center in Yangzhou University. According to the movement of kneading block, the bed body, the grind head, the head frame and wheel dressing mechanical structure of kneading block grinding machine can be designed to meet the requirements of precision, stiff and structure rationalization.
The control system of kneading block NC grinding machine based on PMAC motion controller uses the“PMAC+PC”structure to study and develop special purpose grinding machine system, building system development platform on PC directly, realizing blocking division of the function of software and hardware, organizing function block coordination work by standard interface and realizing the NC function together. The system that we studied is a control system, which can make the program decade explain, the interpolation algorithm, the servo control and the system administration work at a time. It has not only a common commercial NC system’s general function, but also does the specific function for kneading block grinder, such as parameter input, calculation of wheel dressing trajectory, kneading block grinding and the wheel dressing program performing automatically. Meanwhile the system developers and the lathe users can add or delete function block according to real time requirement.
The available and practical parameter of grinding kneading block can be obtained by grinding experiments. So does the optimum ones, which makes a contribution to gain the high grinding efficiency and quality.
捏合块磨削时,由于其形状的特殊性,若零件以匀角速度旋转,则捏合块轮廓面各磨削点的线速度、磨削力等都不一样,这将严重影响磨削质量,如产生波纹、烧伤和形状误差等。针对国内现有加工工艺的不足,我们提出了挤出机捏合块等线速磨削的工艺方法。在对捏合块进行结构分析的基础上,以单位时间内等弧长进行磨削,建立捏合块等线速磨削的数学模型,计算砂轮中心的运动轨迹,自动生成NC数控指令,经实际磨削试验,取得了较好的磨削效果。
本论文在扬州大学机电研究所帮助支持下,在外圆磨床基础上改造了一台捏合块数控磨床,根据捏合块磨削所需的运动对外圆磨床的床身、磨头和头架进行了改造,设计了砂轮修整装置,满足了捏合块磨床的精度、刚性和结构合理性要求。
所改造的捏合块数控磨床控制系统是以PMAC伺服运动控制器为基础,采用“PMAC+PC”的结构形式研制和开发了专用磨床数控系统,将系统开发平台直接构建于PC微机基础之上,实现软硬件功能模块化,各功能模块之间通过标准的接口协调工作,共同完成捏合块磨削所需的数控功能。所研制的系统具有程序译码解释、插补计算、伺服控制、系统管理等控制功能,它不仅具备了一般商用数控系统所要求的通用功能,而且还具备了捏合块磨床所必需的参数输入、砂轮修整轨迹计算、捏合块磨削和砂轮修整程序自动生成等特定功能。同时,系统还为用户设置了今后根据需求增减的模块。
本论文通过捏合块磨削工艺试验,获取了实用可行的捏合块磨削参数。并对磨削参数进行了优化,使捏合块磨削具有较高的磨削效率和质量。
Kneading blocks are a kind of screw elements wildly used in co-rotating twin screw extruders, with complicated shape and high precision. At present, it’s lag in technology for kneading block manufacturing, or say, the outline precision of kneading block can not be ensured, which influences the whole property of extruders greatly. Therefore, studying the mechanism of grinding process, resolving the key problems of developing NC grinding machine and developing advanced and effective machine will improve our country manufacture technology level of twin screw extruder undoubtedly.
If part rotates at a constant angular velocity during grinding process for its special shape, the linear velocity and grinding force of each grinding point on kneading block profile is different, which influences the grinding quality terribly, resulting in wave, burn and shape errors occurrence. In order to make up the defect of present manufacturing technology, we bought forward the new technology of equal linear velocity grinding. Based on kneading blocks' structure analysis, making the machine grind with equal arc length per unit time, we built up the mathematical model of the equal linear velocity grinding. During the manufacturing process, numerical control instruction can be produced and the trajectory of wheel center can be calculated automatically. Modified by real grinding experiments, the grinding effective is very good.
Kneading block NC grinding machines have already been succeeded developing by the mechano-electronic study center in Yangzhou University. According to the movement of kneading block, the bed body, the grind head, the head frame and wheel dressing mechanical structure of kneading block grinding machine can be designed to meet the requirements of precision, stiff and structure rationalization.
The control system of kneading block NC grinding machine based on PMAC motion controller uses the“PMAC+PC”structure to study and develop special purpose grinding machine system, building system development platform on PC directly, realizing blocking division of the function of software and hardware, organizing function block coordination work by standard interface and realizing the NC function together. The system that we studied is a control system, which can make the program decade explain, the interpolation algorithm, the servo control and the system administration work at a time. It has not only a common commercial NC system’s general function, but also does the specific function for kneading block grinder, such as parameter input, calculation of wheel dressing trajectory, kneading block grinding and the wheel dressing program performing automatically. Meanwhile the system developers and the lathe users can add or delete function block according to real time requirement.
The available and practical parameter of grinding kneading block can be obtained by grinding experiments. So does the optimum ones, which makes a contribution to gain the high grinding efficiency and quality.
引文
【1】耿孝正.双螺杆挤出机及其应用. 中国轻工业出版社. 2003.01
【2】李善术. 数控机床及其应用 . 北京:机械工业出版社,2001
【3】王润孝,秦现生. 机床数控原理与系统 . 西安:西北工业大学出版社,1997
【4】王隆太等. 铲齿车床改造为螺杆数控磨床的技术研究 . 扬州大学报 2000(4)
【5】刘慧. 啮合同向双螺杆挤出机几何学的研究. 河北轻化工学院学报, 1997 年第3 期
【6】王文熙.经济型凸轮轴磨床数控系统 制造技术与机床,1999(8)
【7】龚时华 朱国力 段正澄.凸轮磨削加工 CNC 系统关键技术 制造业自动化,2000(4)
【8】金建新,来传远.平面凸轮曲线的等线速度数控磨削方法.中国机械工程, 2002年 5 月下半月
【9】元茂兴. Delta Tau Data System Inc
【10】元茂兴. PMAC 用户手册版本 1.0
【11】元茂兴. PMAC 软件手册版本 1.0
【12】程文斌,金相风等. Visual C++实用大全 . 北京:北京航空航天大学出版社,1995
【13】程文斌等. Microsoft C/C++和 Visual C++ C 库函数和 MFC 库类详解 . 北京:北京航空航天大学出版社,1995
【14】严培军. 磨床经济型数控系统的研制及应用 . 磨床与磨削 1997(1)
【15】帅梅等. 五轴五联动数控系统的开发研制 . 组合机床与自动化加工技术 1998(10)
【16】王春,温圣等. 基于 PMAC 的并行双 CPU 开放式数控系统 . 制造技术与机床 2000(3)
【17】Manas-Zloczower,Haur-Horng Yang.Flow Field Analysis of the Kneading Disc Region in a Co-rotating Twin Screw Extruder.Polym .Eng .Sci,Mid-October,1992,Vol .32,No .19
【18】陈志强.硕士论文.北京化工大学,1998
【19】David B.Todd .Plastics Compounding.Munich:Hanser Publisher,1998
【20】金钰,胡德,李向春. 伺服系统设计指导 . 北京:北京理工大学出版社,2000
【21】杨有君. 数字控制技术与数控机床 . 北京:机械工业出版社,1999
【22】王春,温圣等. 基于 PMAC 的并行双 CPU 开放式数控系统 . 制造技术与机 床 2000(3):p15-17
【23】孟璇,刑玉生,王春. 基于 PMAC 的并行双 CPU 开放式数控系统的研究与开发 . 组合机床与自动化加工技术 2000(10):28-30
【24】富大伟,吴玉厚,张玉. 用 PMAC 实现精确从动 . 机械与电子 2001(1):p6-7
【25】沈兵,黄健. 基于Windows9X的数控系统实时控制研究 . 微型机与应用2002(1): p41-43
【26】宋本基,张铭钧. 数控技术 . 哈尔滨:哈尔滨工程大学出版社,1999
【27】崔玉德,凸轮轴廓面磨削振纹分析,柴油机设计与制造,1996 (1)
【28】杨福田,凸轮磨削过程动态分析的解析法,机械工艺师,1996(1)
【29】韩秋实、王红军、张怀存、许宝杰、朱骥北,PC 控制的现代数控凸轮轴磨床设计方法,制造技术与机床,1999 (2)
【30】汪学明,数控凸轮轴磨床的应用与研制概况,磨床与磨削,1993 (2)
【31】王剑锋,NC 凸轮磨削利弊谈,磨床与磨削,1998 (4)
【32】郭三学、赵陕冬、吴琦,凸轮磨削点移动速度的计算方法,磨床与磨削,1998(4)
【33】韩秋实、许宝杰、王红军、涂志,磨削时凸轮转动变速规律的研究,机械工艺师,2000 (4)
【34】龚时华,基于开放式数控的凸轮轴磨削加工,制造业自动化,2001 (1)
【35】张新永,砂轮直径的变化对凸轮升程的影响与对策,机械工艺师,1993(7)
【36】朱国力、龚时华、段正澄,基于 MACRO 总线的开放式凸轮轴磨床数控系统,制造业自动化,2000 (8)
【37】李伯民,实用磨削技术,机械工业出版社
【38】傅杰才,磨削原理与工艺,湖南大学出版社
【39】谭奇瑞,凸轮磨削动态特性对磨削质量的影响,机械工艺师,1994 (5)
【40】王维春、冯亦英、张岩,凸轮磨削中廓线升程的分析,组合机床与自动化加工技术,1996 (9)
【41】王润孝,机床数控原理与系统,西北工业大学出版社
【42】任敬心,磨削原理,西北工业人学出版社.
【43】邓朝晖、罗重常,现代磨削技术,湖南大学机械与汽车工程学院
【44】郭三学、巩青歌、赵陕冬,凸轮廓形加工误差的动态分析,机械科学与技术,1996 (9)
【45】王桥医,高速磨削时的优选磨削参数,机械制造,1996 (10)
【46】曲贵龙,磨削加工技术的发展趋势,磨床与磨削,2000 (4)
【47】张一同,凸轮轴仿形加工的恒速磨削,制造技术与机床,2000(3)
【48】吴炎辉、李刚炎、杨明忠、钱西汉,凸轮轮廓设计的速度瞬心法,机械工程师,1997 (6)
【49】张迎春、李修仁、高胜利,由动态弧长确定磨削凸轮时的变速规律,组合机床与自动化加工技术,2000 (11)
【50】张迎春、张艳萍、黄建伟,由弧长确定磨削凸轮时的变速规律,机械工程师,2000(8)
【2】李善术. 数控机床及其应用 . 北京:机械工业出版社,2001
【3】王润孝,秦现生. 机床数控原理与系统 . 西安:西北工业大学出版社,1997
【4】王隆太等. 铲齿车床改造为螺杆数控磨床的技术研究 . 扬州大学报 2000(4)
【5】刘慧. 啮合同向双螺杆挤出机几何学的研究. 河北轻化工学院学报, 1997 年第3 期
【6】王文熙.经济型凸轮轴磨床数控系统 制造技术与机床,1999(8)
【7】龚时华 朱国力 段正澄.凸轮磨削加工 CNC 系统关键技术 制造业自动化,2000(4)
【8】金建新,来传远.平面凸轮曲线的等线速度数控磨削方法.中国机械工程, 2002年 5 月下半月
【9】元茂兴. Delta Tau Data System Inc
【10】元茂兴. PMAC 用户手册版本 1.0
【11】元茂兴. PMAC 软件手册版本 1.0
【12】程文斌,金相风等. Visual C++实用大全 . 北京:北京航空航天大学出版社,1995
【13】程文斌等. Microsoft C/C++和 Visual C++ C 库函数和 MFC 库类详解 . 北京:北京航空航天大学出版社,1995
【14】严培军. 磨床经济型数控系统的研制及应用 . 磨床与磨削 1997(1)
【15】帅梅等. 五轴五联动数控系统的开发研制 . 组合机床与自动化加工技术 1998(10)
【16】王春,温圣等. 基于 PMAC 的并行双 CPU 开放式数控系统 . 制造技术与机床 2000(3)
【17】Manas-Zloczower,Haur-Horng Yang.Flow Field Analysis of the Kneading Disc Region in a Co-rotating Twin Screw Extruder.Polym .Eng .Sci,Mid-October,1992,Vol .32,No .19
【18】陈志强.硕士论文.北京化工大学,1998
【19】David B.Todd .Plastics Compounding.Munich:Hanser Publisher,1998
【20】金钰,胡德,李向春. 伺服系统设计指导 . 北京:北京理工大学出版社,2000
【21】杨有君. 数字控制技术与数控机床 . 北京:机械工业出版社,1999
【22】王春,温圣等. 基于 PMAC 的并行双 CPU 开放式数控系统 . 制造技术与机 床 2000(3):p15-17
【23】孟璇,刑玉生,王春. 基于 PMAC 的并行双 CPU 开放式数控系统的研究与开发 . 组合机床与自动化加工技术 2000(10):28-30
【24】富大伟,吴玉厚,张玉. 用 PMAC 实现精确从动 . 机械与电子 2001(1):p6-7
【25】沈兵,黄健. 基于Windows9X的数控系统实时控制研究 . 微型机与应用2002(1): p41-43
【26】宋本基,张铭钧. 数控技术 . 哈尔滨:哈尔滨工程大学出版社,1999
【27】崔玉德,凸轮轴廓面磨削振纹分析,柴油机设计与制造,1996 (1)
【28】杨福田,凸轮磨削过程动态分析的解析法,机械工艺师,1996(1)
【29】韩秋实、王红军、张怀存、许宝杰、朱骥北,PC 控制的现代数控凸轮轴磨床设计方法,制造技术与机床,1999 (2)
【30】汪学明,数控凸轮轴磨床的应用与研制概况,磨床与磨削,1993 (2)
【31】王剑锋,NC 凸轮磨削利弊谈,磨床与磨削,1998 (4)
【32】郭三学、赵陕冬、吴琦,凸轮磨削点移动速度的计算方法,磨床与磨削,1998(4)
【33】韩秋实、许宝杰、王红军、涂志,磨削时凸轮转动变速规律的研究,机械工艺师,2000 (4)
【34】龚时华,基于开放式数控的凸轮轴磨削加工,制造业自动化,2001 (1)
【35】张新永,砂轮直径的变化对凸轮升程的影响与对策,机械工艺师,1993(7)
【36】朱国力、龚时华、段正澄,基于 MACRO 总线的开放式凸轮轴磨床数控系统,制造业自动化,2000 (8)
【37】李伯民,实用磨削技术,机械工业出版社
【38】傅杰才,磨削原理与工艺,湖南大学出版社
【39】谭奇瑞,凸轮磨削动态特性对磨削质量的影响,机械工艺师,1994 (5)
【40】王维春、冯亦英、张岩,凸轮磨削中廓线升程的分析,组合机床与自动化加工技术,1996 (9)
【41】王润孝,机床数控原理与系统,西北工业大学出版社
【42】任敬心,磨削原理,西北工业人学出版社.
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