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PE 10无级变速自行车设计(毕业论文)

2017-09-02 50页 doc 313KB 35阅读

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PE 10无级变速自行车设计(毕业论文)PE 10无级变速自行车设计(毕业论文) PE10自行车无级变速器设计 摘 要:本文在分析各种无级变速器和无级变速自行车的基础上,把钢球外锥式无级变速器进 行部分改装,从而形成了自行车的无级变速装置。该装置通过八个钢球利用摩擦力将动力进行输入 输出,用一对斜齿轮进行分度调速,从而使自行车在0.75,1.22之间进行无级调速。研究表明:无 级变速器被用于自行车方面可以大大改善自行车的使用性能,方便广大消费者使用。 关键字: 无级变速自行车;无级变速器 The design of the CVT on PE 10 bicy...
PE 10无级变速自行车设计(毕业论文)
PE 10无级变速自行车(毕业) PE10自行车无级变速器设计 摘 要:本文在分析各种无级变速器和无级变速自行车的基础上,把钢球外锥式无级变速器进 行部分改装,从而形成了自行车的无级变速装置。该装置通过八个钢球利用摩擦力将动力进行输入 输出,用一对斜齿轮进行分度调速,从而使自行车在0.75,1.22之间进行无级调速。研究表明:无 级变速器被用于自行车方面可以大大改善自行车的使用性能,方便广大消费者使用。 关键字: 无级变速自行车;无级变速器 The design of the CVT on PE 10 bicycle ABSTRACT: Based on the analysis of various CVT and CVT bikes,in this dissertation ,we change some parts of the Kopp-B CVT forming a new kind of CVT used to the bicycle .They are used to input or output the power through the friction and a pair of helical gears is also used to adjust the speed, so the speed can change between 0.75 and 1.22.This research shows that when the CVT are used in the bicycle ,they can significant improve the performance of bike so that all customers can use it convenient. Keyword: CVT bike; CVT 1 第一章 绪论 ?1.1 机械无级变速器的发展概况 无级变速器分为机械无级变速器,液压传动无级变速器,电力传动无级变速器三种,但本设计任务要求把无级变速器安装在自行车上,所以一般只能用机械无级变速器,所以以下重点介绍机械无级变速器。 机械无级变速器最初是在19世纪90年代出现的,至20世纪30年代以后才开始发展,但当时由于受材质与工艺方面的条件限制,进展缓慢。直到20世纪50年代,尤其是70年代以后,一方面随着先进的冶炼和热处理技术,精密加工和数控机床以及牵引传动理论与油品的出现和发展,解决了研制和生产无级变速器的限制因素;另一方面,随着生产工艺流程实现机械化、自动化以及机械要改进工作性能,都需要大量采用无级变速器。因此在这种形式下,机械无级变速器获得迅速和广泛的发展。主要研制和生产的国家有美国、日本、德国、意大利和俄国等。产品有摩擦式、链式、带式和脉动式四大类约三十多种结构形式。 国内无级变速器是在20世纪60年代前后起步的,当时主要是作为专业机械配套零部件,由于专业机械厂进行仿制和生产,例如用于纺织机械的齿链式,化工机械的多盘式以及切削机床的Kopp型无级变速器等,但品种规格不多,产量不大,年产量仅数千台。直到80年代中期以后,随着国外先进设备的大量引进,工业生产现代化及自动流水线的迅速发展,对各种类型机械无级变速器的需求大幅度增加,专业厂才开始建立并进行规模化生产,一些高等院校也开展了该领域的研究工作。经过十几年的发展,国外现有的几种主要类型结构的无级变速器,在国内皆有相应的专业生产厂及系列产品,年产量约10万台左右,初步满足了生产发展的需要。与此同时,无级变速器专业协会、行业协会及情报网等组织相继建立。定期出版网讯及召开学术信息会议进行交流。自90年代以来,我国先后制定的机械行业共14个: 1. JB/T 5984-92 《宽V带无级变速装置基本参数》 2. JB/T 6950-93 《行星锥盘无级变速器》 3. JB/T 6951-93 《三相并联连杆脉动无级变速器》 4. JB/T 6952-93 《齿链式无级变速器》 5. JB/T 7010-93 《环锥行星无级变速器》 6. JB/T 7254-94 《无级变速摆线针轮减速机》 7. JB/T 7346-94 《机械无级变速器试验》 8. JB/T 7515-94 《四相并列连杆脉动无级变速器》 9. JB/T 7668-95 《多盘式无级变速器》 10.JB/T 7683-95 《机械无级变速器 分类及型号编制方法》 2 11.JB/T 7686-95 《锥盘环盘式无级变速器》 12.JB/T 50150-1999 《行星锥盘无级变速器 质量分等》 13.JB/T 53083-1999 《三相并联连杆脉动无级变速器 质量分等》 14.JB/T 50020-×××× 《无级变速摆线针轮减速机产品质量分等》(报批稿) 现在,机械无级变速器从研制、生产、组织管理到情报网信息各方面已组成一较完 整的体系,发展成为机械领域中一个新型行业。 ?1.2 机械无级变速器的特征和应用 机械无级变速器是一种传动装置,其功能特征主要是:在输入转速不变的情况下,能实现输出轴的转速在一定范围内连续变化,以满足机器或生产系统在运转过程中各种不同工况的要求;其结构特征主要是:需由变速传动机构、调速机构及加压装置或输出机构三部分组成。 机械无级变速器的适用范围广,有在驱动功率不变的情况下,因工作阻力变化而需要调节转速以产生相应的驱动力矩者(如化工行业中的搅拌机械,即需要随着搅拌物料的粘度、阻力增大而能相应减慢搅拌速度);有根据工况要求需要调节速度者(如起重运输机械要求随物料及运行区段的变化而能相应改变提升或运行速度,食品机械中的烤干机或制药机械要求随着温度变化而调节转移速度);有为获得恒定的工作速度或张力而需要调节速度者(如断面切削机床加工时需保持恒定的切削线速度,电工机械中的绕线机需保持恒定的卷绕速度,纺织机械中的浆纱机及轻工机械中的薄膜机皆需调节转速以保证恒定的张力等);有为适应整个系统中各种工况、工位、工序或单元的不同要求而需协调运转速度以及需要配合自动控制者(如各种各样半自动或自动的生产、操作或装配流水线);有为探求最佳效果而需变换速度者(如试验机械或李心机需调速以获得最佳分离效果);有为节约能源而需进行调速者(如风机、水泵等);此外,还有按各种规律的或不规律的变化而进行速度调节以及实现自动或程序控制等。 综上所述。可以看出采用无级变速器,尤其是配合减速传动时进一步扩大其变速范围与输出转矩,能更好的适应各种工况要求,使之效能最佳,在提高产品的产量和质量,适应产品变换需要,节约能源,实现整个系统的机械化、自动化等各方面皆具有显著的效果。故无级变速器目前已成为一种基本的通用传动形式,应用于纺织、轻工、食品、包装、化工、机床、电工、起重运输矿山冶金、工程、农业、国防及试验等各类机械。 3 ?1.3 无级变速自行车研究现状 自行车发展到现在已经有传统的自行车演变成无级变速自行车,现代的无级变速自行车可谓是形式多样,五花八门,以下是当今社会上存在的部分无级变速自行车。 1. 低座无级变速自行车 是由低矮形车架把一个作驱动的前轮和一个作导向的后轮连接在一块的自行车,带靠背的座椅安装在车架中部,骑行者可斜躺着坐在座椅上,两腿放在前轮二侧。杠杆式曲柄无级传动装置固定在前轮的前上方,通过左右曲柄杆上的滑块铰接链条交替传动前轮。操纵把手装于前轮的正上方,由钢丝绳牵引后轮转向。这样就不会干扰车子的方向操纵。由于降低了座位高度,减少了空气阻力。采用杠杆式曲柄无级传动装置,适应人体功能的要求。 2. 人力脚踏式无级变速自行车 一种人力脚踏式无级变速自行车,在自行车车架两侧面的中轴上,安装有锥面相对的变速轮盘组成的主动轮,主动轮两侧安装有脚蹬两变速轮盘轮沿挂有三角皮带,两盘面间安装有压缩弹簧;在车架的前斜梁上,安装有由变速杆操纵可前后移动的挺杆,挺杆的近变速轮盘端安装有可使两变速轮盘靠近或分离的插件;在自行车后轴上的后轮轮辐两侧面支承有附轮,附轮的外沿轮面设有三角皮带槽,附轮的内侧设有带动后轮单向转动的棘齿;车架后斜梁上在三角皮带上方安装有可推压三角皮带张紧的张紧轮。自行车的行走和变速不用成组链轮和链条传动,成本低、重量轻,可实现无级变速,速度转换快,速比大。 3. 带传动无级变速自行车 一种无级变速自行车,改进了现有自行车的动力传动机构。该自行车的动力传动机构包括以下部件:小动轮、小定轮、小动轮拨叉,小动轮、大动轮、大定轮、大动轮拨叉,大动轮、,型传动带、,型带张紧装置、调速器、闸线、飞轮,飞轮由飞轮轴套、飞轮底座、滚柱、滚珠构成。其特征在于自行车的动力传动机构包括以下部件:小动轮、小定轮、小动轮拨叉,小动轮、小定轮呈锥形,两轮大小形状一致,锥面相对,组成带有,形沟槽的小传动轮,与自行车后轴上的飞轮轴套固定连接,小动轮在拨叉控制下沿轴滑动;大动轮、大定轮、大动轮拨叉,大动轮、大定轮也呈锥形,两轮大小形状一致,锥面相对,组成带有,形沟槽的大传动轮,固定在自行车中轴上,大动轮在拨叉控制下沿轴滑动;,型传动带、,型带张紧装置、调速器、闸线、飞轮,,型传动带镶在大小轮的沟槽中;,型带张紧装置装在后轴上,其支承轮支撑传动带;调速器装在车把附近,与闸线连接,闸线带动调节大小动轮位置的拨叉;飞轮由飞轮轴套、飞轮底座、滚柱、滚珠构成,装在后轴上,靠紧小传动轮,飞轮轴套与小传动轮固定连接,飞轮底座与后轴固定连接,飞轮轴套内还设有流线型的槽,滚柱放置在槽内。 这种无级变速自行车通过带传动来实现自行车的无级变速,传动平稳、噪音低、调速操作方便、变速范围大;同时该无级变速自行车的结构简单、易于加工,可以实现大规模成批生产。 4 4. 针对自行车的驱动、乘座和避震进行改进。包括:乘骑者坐靠休闲式椅,两脚蹬踏前置的两个悬摇杆曲柄,可进行弧形的曲线往复运动,用脚掌面的蹬踏角度或用手直接调动摇杆上力臂的长短实现无级变速,高效能的带动挠性件驱动后轮;还包括装卸方便且不互换的休闲式座椅和防落物防盗的可带走座椅;简化的全避震使乘坐舒适并使货架携带的物品减小了颠簸 5. 纯滚动式四个档位无级变速自行车 一种纯滚动式四个档位无级变速自行车,其中在中轴上的中心齿轮啮合连接有一级行星轮和二级行星轮,中心齿轮的两侧分别套装有推动盘,一侧固定在脚蹬轮轴上,另一侧固定在链轮上;二级行星轮和中心齿轮为棘轮总成与链轮啮合连接,在中轴和后轴的车架体上固定有座盘,座盘上固定有升降档位弹簧;在座盘上固定连接有自锁离合器总成,自锁离合器总成滚动套装在停转盘上,停转盘固定在中轴和后轴上;在中轴和后轴的自锁离合器总成上装有移动升降档位拉杆。随时变增减速档位,对自行车零部件无影响,制造简单,性能可靠,操作简单,使用方便。 6. 无链无级变速自行车 一种无链条传动,可随意变换车速的自行车。该自行车包括车轮、把手、三角架和踏拐等,横梁左端设有后齿轮、大齿轮和正反齿轮,横梁右端设有中轴齿轮,齿轮与拐轴齿轮啮合,偏心连杆的上端和杠杆的右端同轴装在定位槽板的滑槽中,杠杆的左端与齿条连接,齿条与正反齿轮啮合,横梁上方设有拉簧、活动支架和钢丝拉索。该自行车结构简单,调速方便灵活,经久耐用,适合各种型号。 7. 蓄能型-全自动无级变速自行车 一种蓄能型一全自动无级变速自行车,属于交通工具技术领域。本实用新型的目的通过如下技术实现:主要由设置每侧脚蹬上的长型齿盘交替工作,通过同侧的链条传动同侧的飞轮,飞轮连同带动设置在轮骨内的发条内端发条外端同轮骨固定。其中:同每侧的飞轮安装在同一轴套上还设置有防逆转装置,防逆转装置的内部结构如同飞轮,外壳同车架子固定。骑行时由于每侧长型齿盘的作用,通过链条对同侧的发条交替蓄能,从而实现全自动无级变速。本实用新型是现代变速自行车的换代产品。 8. 便携式高安全型无级变速自行车 一种新式样的自行车。其特征是由行走机构,车椅式直立车龙头转向机构,杠杆式无级变速驱动机构。适用于交通拥挤,楼层高,住房紧,停放车辆不便的都市区。本装置是由足踏杠杆式无级变速机构,车架可横向折叠,驱动大车轮在前面,导向小车轮在后边的行走机构与带靠背车坐椅式的直立车龙头转向机构组成的自行车装置。该装置形体式样,较为奇特但骑行舒适,更安全,并能折叠便携带。 5 ?1.4 毕业论文设计内容和要求 设计内容:根据男式自行车的特点选择合适的传动比;比较和选择合适的方案;完成自行车无级变速器变速器的结构设计与计算;对关键部件进行强度和寿命校核。 设计要求:传动比范围0.75,1.22;变速器尺寸要尽可能小,轻便;结构设计时应使制造成本尽可能低;安装拆卸要方便;外观要匀称,美观;调速要灵活,调速过程中不能出现卡死现象,能实现动态无级调速;关键部件满足强度和寿命要求;画零件图和装配图。 6 第二章 自行车无级变速器总体方案的选择 自行车无级变速方式多种多样,在此,我只选择了两种方案供参考,作比较,选出理想方案。该两种方案分别是钢球长锥式(RC型)无级变速器和钢球外锥式无级变速器,分别描述如下。 ?2.1 钢球长锥式(RC型)无级变速器 钢环 调速锥轮 图2-1 钢球长锥式(RC型)无级变速器 如上图所示,为一种早期生产的环锥式无级变速器,是利用钢环的弹性楔紧作用自动加压而无需加压装置。由于采用两轴线平行的长锥替代了两对分离轮,并且通过移动钢环来进行变速,所以结构特别简单。但由于长锥的锥度较小,故变速范围受限制。 RC型变速器属升、降速型,其机械特性如下图所示。技术参数为:传动比 i = n/n =2,21210.5,变速比R = 4,输入功率P=(0.1,2.2) kw ,输入转速 n=1500 r/min ,传动效b11 率η,85% 。一般用于机床和纺织机械等. 下图是RC型变速器的机械特性: PT22 P2 T2 n20 图2-2 RC型变速器的机械特性 ?2.2 钢球外锥式无级变速器 7 1,11-输入,输出轴 2,10-加压装置 3,9-主,从动锥轮 4-传动钢球 5-调速蜗轮 6-调速蜗杆 7-外环 8-传动钢球轴 12,13-端盖 图2-3 钢球外锥式无级变速器 如图所示,动力由轴1输入,通过自动加压装置2,带动主动轮3同速转动,经过一组(3,8)钢球4利用摩擦力驱动输出轴11,最后将运动输出。传动钢球的支承轴8的两端,嵌装在壳体两端盖12和13的径向弧行倒槽内,并穿过调速涡轮5的曲线槽;调速时,通过蜗杆6和蜗轮5转动,由于曲线槽的作用使钢球轴线的倾斜角发生变化,导致钢球与两锥轮的工作半径改变,输出轴转速得到调节。其动力范围为:R=9,nI=1/I,P?11 kw ,ε?4% ,η,0.80,0.92 。此种变速器应用广泛。 maxmin 从动调速齿轮5的端面分布一组曲线槽,曲线槽数目与钢球数相同。曲线槽可用阿基米德螺旋线,也可用圆弧。当转动主动齿轮6使从动齿轮5转动时,从动齿轮的曲线槽迫使传动钢球轴8绕钢球4的轴心线摆动,传动轮3以及从动轮9与钢球4的接触半径发生变化,实现无级调速。具体分析如下: 图2-4 钢球外锥式无级变速器变速示意图 8 主要由两个锥轮1、2和一组钢球3(通常为6个)组成。主、从动锥轮1和2分别装在轴?、?上,钢球3被压紧在两锥轮的工作锥面上,并可在轴4上自由转动。工作时,主动锥轮1依靠摩擦力带动钢球3绕轴4旋转,钢球同样依靠摩擦力带动从动锥轮2转动。轴?、?传动比 ,由于 ,所以 。调整支承轴4的倾斜角与倾斜方向,即可改变钢球3的传动半径r和r,从而实现无级变速。 12 ?2.3 两方案的比较与选择 钢球长锥式(RC型)无级变速器结构很简单,且使用参数更符合我们此次设计的要求,但由于在调速过程中,怎样使钢环移动有很大的难度,需要精密的装置,如果此装置用于自行车,成本会大大的提高,显得不合理。 而钢球外锥式无级变速器的结构也比较简单,原理清晰,各项参数也比较符合设计要求,故选择此变速器。只是字选用此变速器的同时须对该装置进行部分更改。 须更改的部分是蜗轮蜗杆调速装置部分。因为我们是选用了8个钢球,曲线槽设计 0见第三章,一个曲线槽跨度是90,也就是说自行车从最大传动比调到最小传动比,需 0要使其转过90,而普通蜗轮蜗杆传动比是1/8,那么其结构和尺寸将完全不符合我们设计的要求。为此,我们想到了将它们改为两斜齿轮传动,以用来调速。选用斜齿轮是因为斜齿轮传动比较平稳。在设计过程中,将主动斜齿轮的直径设计成从动斜齿轮的3/4, 00这样只要主动轮转动120,那么从动轮就会转动90,符合设计要求。 9 第三章 钢球外锥式无级变速器部分零件的设计与计算 钢球外锥式无级变速器零件的设计与计算包括主)从动锥齿轮,加压盘,调速齿轮 上变速曲线槽,输入轴,输出轴,输入)输出轴上轴承,输入)输出轴上端盖,调速机 构等部分的设计与计算,以下各章节分别介绍以上内容。 ?3.1 钢球与主)从动锥齿轮的设计与计算 ,,P,,m,m,g,v,,输入功率 11人车变 ,,,0.1,65,20,9.8,4.17,0.86 =0.4039 kw 其中: m,65m,20,,0.86,,0.1, kg, kg, , km/h m/s, g,9.8v,15,4.171人车变 d,560轮胎直径: mm 1 由力学知识可得:轮胎所产生的转矩与钢球摩擦所产生的转矩应平衡 2,,,m,m,g,,,R,8,Q,,,c,d,N 1121q人车3 R,280,,0.1c,2.16其中: mm ,, , Q为钢球所受正压力 121 代入数据可得: Q,d,17997 q 179974, 3σ=1353×=1353×=56284/dQ,Kd3Hmaxq3dq 由于传动件的[σ]=2200,2500 Mpa 带入上式得: j d,22.51, mm ,取 d=25 mm,钢球数 25.58z,8qq 15000,60输出转速 n==142.3 r/min 23600,0.66,, 输入转速 n=142.3/(0.75,1.22)=189.7,116.6 r/min 1 I,1.22,I,0.75传动比 maxmin 1.22R,,1.63变速范围 n0.75 钢球支轴的极限转角θ 10 00///,,,,arctanI,45,arctan1.22,53934 增速方向 1max 00///,,,,arctanI,45,arctan0.75,8748 减速方向 2min D,D,c,d,2.16,25,54圆锥工作直径 mm 121q ,,D,c,cos,,d,71.7钢球中心圆直径 mm 31q ,,0d钢球侧隙 [,,]×=[]×25=2.43 mm c,cos,sin,1,,2.16,cos45sin,1q18z D,D,d,71.7,25,96.7外环内经 mm r3q 外环轴向截面圆弧半径 R=(0.7,0.8)×d=(0.7,0.8)×25=17.5,20 mm ,取 R=18 mm q 锥轮工作圆之间的轴向距离 0 mm B,d,sin,,25,sin45,17.68q ?3.2 加压盘的设计与计算 加压盘的作用直径 d = (0.5,0.6) × D= (0.5,0.6) × 54 = 27,32.4 mm 1 p d,30取 mm p //0,arctanf,arctan0.15,8.53,滑动摩擦角 c 加压盘V形槽倾角 fD0 1 λ=arctan =14.85dsin,p 传动钢球的确接触应力为 17997,433 σ=1353×=1353×=2251.35 Mpa ?[σ] Q,Kdj325 2,1.1,9550000,0.4039,0.85每个钢球作用在V形槽侧面的正压力 Q= y08,30,sin14.85,180 =651.6 N 1.1,651.6K,Q zY3用钢球加压装置时 σ=1370×=1370×3jmax224rq =4865.6 Mpa ?[σ] j 11 其中:[σ]为4000,5000 Mpa j r,4钢球半径 mm q B,2r/cos,,8.27 mm q 碟形弹簧预紧力为200 N ,结构设计如下图所示: 图3-1 加压装置 ?3.3 调速齿轮上变速曲线槽的设计与计算 00 0槽的张角ψ=80,12,取ψ=90。 (1)变速曲线槽的槽形曲线为圆弧,中心线上三个特殊点 A,B,C的坐标系(以O 为极点)分别为: 0I,I,1.22,,0时, maxA 0///R,0.5D,lsin,,0.5,71.7,15.5,sin8248,33.66 mm A3max ,,l,0.5d,,,,,0.55,25,其中:(0.5,1.0)=(0.5,1.0)=15.5 mm q I1.2200max,, I=1时 ,ψ= =,90=49.46 B1,I1,1.22max R,0.5D,0.5,71.7,35.85 mm B3 0,,,,90I,I,0.75 时 ,, Cmin 0///R,0.5D,lsin,,0.5,71.7,15.5,sin5748,38 mm C3min 12 图3-2 调速论 ”(3)用通过三点作圆弧的方法确定槽圆弧确定曲线半径R和中心O (4)要求传动比I与齿轮转角ψ呈线性变化时,槽形曲线方程为: x R=05D+lsinθ ()ψ.3 ,,,I,I,I,,,,1maxmaxmincot,=0.5D+lsin,arctan[], 3,,,,,I,I,I1,maxmaxmin ,,,,,,,,,11.221.220.750cot45=0.5×71.7+15.5sin,arctan[], ,,,,,,,,,11.221.220.75 0,0.47,19.8=35.85+15.5sin(arctan) 019.8,0.47, ?3.4 输入轴的设计与计算 P,0.40931.输入轴上传递的功率为 kw 输入 转速 n=189.7,116.6 r/min ,取 n=135 r/min 11 P0.4039入转矩 T=9550000=9550000×=28572 N?mm 1n1351 2.如图所示,作用于锥轮的正压力 Q 13 图3-3 正压力计算示意图 Q,d,17997d,25 由前计算可知: , 其中mm qq 17997 所以 N Q,,8,4909.6总25 0F,613.7,sin45,433.95 单个锥轮的轴向力 Fa=径向力 N t 3.初步确定轴的最小直径 选取轴的材料是40Cr ,调质处理 .取A=100 ,于是得: 0 0.4039P入3Ad ==100×=14.4 mm ,取 d=14.5 mm 3min min0180n1 4.轴的结构设计 图3-4 输入轴 如图所示,?-?段装飞轮, ?-?段装端盖, ?-?段装轴承1,规格是d=17 mm , ?1? ?-?段为轴肩,d=19.4 mm,?-?段装轴承2,规格d=12 mm ,?-? ,?-?段装压?2? 紧装置以及装锥轮,具体尺寸如零件图所示 求轴上的载荷 ?-?段不承受径向载荷 两轴承的距离为 mm 9,8,8,2.1,2,29.1 1飞轮压轴力方向线与轴承?的距离为 mm 9.9,5,14.5 14 图3-5 压轴力受力模型 a.计算压轴力F p ,,ppnz11F,K,F F=1000 v= epFPe60,1000v选定链条型号和节距 查《机械设计》表9-7,9-13,单排链 P,KKP,1.0,0.58,0.4039,0.234 kw CAAZ ’/n,90 r/min由P和n的值查《机械设计》图9-11,得可选10A-1,链条节距CA mm p,15.875 90,38,15.875故 v==0.904857 m/s 60,1000 1000,0.4039所以 F==446.4 N e0.904875 F,446.1,1.15,513.36所以 n(链条水平布置时的压轴力系数K=1.15) FPp F,FF,F b. 1r12r2 F,14.9,F,29.1 pr2 F,238.2 所以 N r2 F,F,F,F,513.36,238.2,751.56 所以 n r11pr2计算最大弯矩 M,M,513.36,14.9,6622 N.mm nax,,A 5.校核扭矩 403.9PT=9550000=9550×=28572 N?mm n135 22226622,0.6,28572,,,,6622,0.6,28572σ== CA3w0.1,17 15 =34.7 Mpa,[σ]=60 Mpa -1 键槽处轴的校核 2222dbtdt,,14.55,3,12,,,,,, W===224.7 (c)322d322,14.5 0.6,21429 σ== 57.22 Mpa ,[σ]=60 Mpa ()ACCA224.7 6.键强度的校核 平键的尺寸为 ,键槽轴深 t,3.0,k,h,t,2.0b,h,l,5,5,10 32,10T2,21429σ===147.8 Mpa? [σ]=120,150 Mpa ppkld2,10,14.5 满足条件 3花键校核 σ=2T×10/(ψzhld) pm 其中: ψ为载荷分配不均系数,取0.8 花键齿数 z,8 齿的工作长度 mm l,8 花键齿侧的工作高度 mm h,1.5 15,12 花键的平均直径 d,,13.5 mm m2 32,21429T2,10 σ===41.34 Mpa ? [σ]=40,70 Mpa pp0.8,8,1.5,8,13.5,zhldm 花键的连接情况是:使用或制造情况不良,齿面未经热处理,故满足要求 ?3.5 输出轴的设计与计算 ,,P,0.1,65,20,9.8,4.17,0.34741.输出轴上的传递功率为 kw 输出 n,142.3转速 r/min 2 P0.34736出9550000于是转矩 T= =9550000×=23311.9 N?mm 2n142.32 2.作用于锥轮的正压力 Q 由前计算可知: Q,d,17997d,25 , 其中mm qq 16 17997 所以 Q= N ,613.725 0F,613.7,sin45,433.95 单个锥轮的轴向力 Fa=径向力 t 3.初步确定轴的最小直径 选取轴的材料是40Cr ,调质处理 .取A=100 ,于是得: 0 0.34736P出3Ad ==100×=13.5 mm 取d=14.5 mm 3min 0142.3n2 4.轴的结构设计 图3-6 输出轴 ?-?段与输入轴的?-?段完全相同,只有?-?段不一样,输出轴?-?段装的 是后轮轴。这样设计便于统一加工. 5.求轴上的载荷 两轴承的距离为 mm 9,8,8,2.1,2,29.1 1压轴力F与轴承?的距离为mm 35,9.9,44.9合压 合 图3-7 压轴力受力模型 如上图所示 22,,222,,,,65,20,9.8,,N,0.1 F===558.1 N N,f合压,,3,, 2,,N,65,20,9.8,,555.3 N 3 29.1,F,44.9,F,44.9,558.1F,822.8 所以 N r1r2合压 17 F,F,F,822.8,558.1,1380.9 N r1r2合压 6.计算最大弯矩 M,F,29.1,822.8,29.1,23943 N maxr2 7.校核扭矩 /所受扭矩: N?mm T,f,r,T,0.1,555.3,280,15548.4轮 A处校核 2223943,0.6,15548.4,, σ==52.3 Mpa , [σ] Mpa CACA30.1,17 C出校核 2222dbtdt,,14.55,3,12,,,,,,W===224.7 (c)322d322,14.5 0.6,15548.4σ==41.5 Mpa ,[σ]=60 Mpa ()ACCA224.7 故校核安全 8.键强度的校核 平键的尺寸为t,3.0,k,h,t,2.0,键槽轴深 b,h,l,5,5,40 2,15548.42Tσ===26.8 Mpa ? [σ]=120,150 Mpa ppkld2,14.5,40 满足条件 3花键校核σ=2T×10/(ψzhld) pm 其中: ψ为载荷分配不均系数,取0.8 花键齿数 mm z,8 齿的工作长度 l,8 花键齿侧的工作高度 mm h,1.5 15,12 花键的平均直径 d,,13.5 mm m2 32,15548.4T2,10 σ===29.99 Mpa ? [σ]=40,70 Mpa pp0.8,8,1.5,8,13.5,zhldm 花键的连接情况是:使用或制造情况不良,齿面未经热处理,故满足要求 18 ?3.6 输入)输出轴上轴承的选择与计算 1. 输入轴上轴承的寿命计算 Fr1 Fae Fd2Fd1 Fr2 图3-8 输入轴轴承受力计算示意图 00F,8Qsin45,8,613.7,sin45,3313 N ae F,F,F d2d1ae 2轴承被拉松 F,F,0.68,F,0.68,238.2,162 N a2d2r1 F,238.2 N r2 1轴承被压紧 F,F,F,162,3313,3151 N a1d2ae F,751.56 N r1 ,,,,P,fxF,yF,1.0,1,238.2,0,162,238.2所以 轴承2的当量载荷为 N 1pr1a1 轴承1的当量载荷为 ,,,,P,fxF,yF,1.0,0.41,751.56,0.87,3151.7,3050 N 1pr1a1 3366106.310C,,,, 所以 L===1088 h ,,,,,,h160nP60,1353.05,,,, 36105.2,,61.28,10 L=,= h ,,h260,1350.2382,, 2. 输出轴上轴承的寿命计算 19 Fr2 Fae Fd1Fd2 Fr1 图3-9 输出轴轴承受力计算示意图 00F,8Qsin45,8,613.7,sin45,3313N ae F,F,F d2d1ae 2轴承被拉松 F,F,0.68,F,0.68,822.8,559.5 N a2d2r2 F,822.8 N r2 1轴承被压紧 F,F,F,559.3,3313,2753.7 N a1d2ae F,1380.9 N r1 所以轴承1的当量载荷为 ,,,,P,fxF,yF,1.0,0.41,1380.9,0.87,2753.7,2961.7 N 1pr1a1 轴承2的当量载荷为 ,,,,P,fxF,yF,1.0,1,822.8,0,559.5,822.8N 1pr1a1 3366106.310C,,,,所以 L==,=1127.3 h ,,,,,h160nP60,142.32.96,,,, 36105.2,, 4 L==2.942,10h ,h2,,60,142.30.822,, ?3.7 输入)输出轴上端盖的设计与计算 密封件的设计如下:见下图3-10 d,15D,14B,16 轴径 mm , mm , mm , mm D,29111 20 端盖的设计及计算如下:见下图 3-11 1 2 0 0 1146 1 图3-10 密封圈 图3-11 端盖 d,3螺钉直径 mm 3 d,d,1,4 mm 03 D,D,2.5d,35,2.5,3,42.5 mm 03 D,D,2.5d,42.5,2.5,3,50 mm 203 e,1.2d,3.6e,e mm ,取 4 mm 31 mm m,1 D=D–,10,15, mm ,35,10,254 D,D,3d,42.5,9,33.5 mm 503 D=,2,4,==32 mm 35,3D,6 b,10d,16D,28 mm , mm , mm 111 主从动轴一样. ?3.8 调速机构的设计与计算 调速机构采用两斜齿轮分度调速。 1.调速齿轮1的设计与计算 m,2模数 mm n 21 0,,12螺旋角 0,,20法面压力角 n ,端面压力角 t 000tan,,tan,/cos,,tan20/cos12,0.3721,,20.4 所以 tnt ,基圆柱螺旋角 b 000tan,,tan,cos,,tan12cos20.4,0.19921,,11.27 所以 btb 法面齿距 mm P,,m,3.14,2,6.28,nn 0端面齿距 mm P,,m,P/cos12,6.42,tnn 0P,P,cos,,6.28,cos20,5.9法面基圆齿距 mm bnnn ,h,1法面齿顶高系数 an ,c,0.25法面顶隙系数 n 0d,zm,zm/cos,,53,2/cos12,108.37分度圆直径 mm tn 0d,dcos,,108.37,cos20.4,101.57基圆直径 mm bt ,h,mh,2,1,2齿顶高 mm anan ,,齿根高 mm ,,,,h,mh,c,2,1,0.25,2.5fnann d,d,2h,108.37,2,2,112.37齿顶圆直径 mm aa d,d,2h,108.37,2.5,2,103.37齿根圆直径 mm ff 法面齿厚 mm S,/2,m,3.14,nn 0端面齿厚 mm S,/2,m,/cos12,3.21,,tt 330Z,z/cos,,53/cos12,57当量齿数 v 2.主动斜齿轮2的设计与计算 m,2模数 mm n 22 0d,zm,zm/cos,,40,2/cos12,81.79分度圆直径 mm tn 0d,dcos,,81.79,cos20.4,76.66基圆直径 mm bt d,d,2h,81.79,2,2,85.79齿顶圆直径 mm aa d,d,2h,81.79,2.5,2,76.79齿根圆直径 mm ff 330Z,z/cos,,40/cos12,42.74当量齿数 v 其余参数均与调速齿轮1相同. 两齿轮的宽度均为 5 mm . 0但主动斜齿轮只需转过120,所以该斜齿轮只需做成不完全齿轮,具体尺寸见另加图。 ?3.9 自行车无级变速器的安装 无级变速器的输出轴上安装着自行车的后轮,输入轴上安装自行车的后飞轮,整个 变速器位于后轮右侧。变速器的主动调速齿轮上安装摇杆,该摇杆可以伸缩,这样在不 00调速时保证摇杆空间尺寸较小。摇杆可转动120,这样可带动从动调速论转动90,从而 使自行车速度在最大速度和最小速度之间变动。 1、4、7-端盖 2-轴承 3-套筒 5-轴套 6-轴管 图3-12 变速器安装示意图 自行车后轮与输出轴的安装方式如上图所示,1、4、7端盖是用来密封,保护轴承5的,普通自行车的后轴管和花盘是分开的,我这里把它们作成一个整体,即轴管6,与后轴用键连,轴套5的作用是轴向定位轴管,轴承2与轴采用过盈配合,具体尺寸设计见输出轴的零件图。 23 参考文献 [1]濮良贵,纪名刚.机械设计[M].第八版.西安:高等教育出版社, 2005. [2]孙恒,陈作模.机械原理[M].第六版.西安:高等教育出版社, 2000. [3]徐灝.机械设计手册[M].第三卷.北京:机械工业出版社, 1991. [4]吴宗泽,罗圣国.机械设计课程设计手册[M].第三版.北京:高等教育出版社, 2006. [5]周良德,朱泗芳.现代工程图学[M].湘潭:湖南科学技术出版社, 2000. [6]周有强.机械无级变速器[M].成都:机械工业出版社, 2001. [7]李新,洪泉,王艳梅.国内外通用标准件手册[M].南京:江苏科技出版,凤凰出版传媒集团, 2006. [8]葛志淇.机械零件设计手册[M].天津:冶金工业出版社,1980. 24 心得与体会 经过为时两个月的努力,我的毕业设计终于告一段落了。 在这两个月的时间里,我查阅了很多关于这次设计的资料,也学到了不少东西。首先,画图方面,我们用CAD制图,这让我熟悉了CAD的制图方法,为我两个月后走上工作岗位打下了一个好的基础。其次,论文的撰写与编辑方面,里面的章章节节都经过了我的细心编排经过周友行副教授的指导,让我深刻领略到了,论文编写的严谨性,我想我以后如果有机会发表某些论文的话,就不会再无从下手了。再次,这个课题是我和同学谭浩共同完成的,这让我再次体会到了分工与协作的重要性,设计过程中,一般他在网上找资料,我去图书馆找,这样我们俩同时获得内容就比较丰富,另外,在方案选择方面,我们两各自提出了自己的方案,然后经过我们的讨论与分析,最终选定设计方案,我想这无形中也增强了我们分析和解决问题的能力。 设计过程中,我们查阅了许多课本上没有的内容和资料,大大的丰富了我的大脑,让我们懂得了更多的只是,有人说毕业设计才是我们真正开始掌握知识的时候,我现在觉得也挺有道理的。 最后,要感谢指导老师周友行副教授和邱爱红老师的悉心指导和热情帮助,周老师每个星期固定和我们至少见一次面,审查我们的进度,帮我们解决前期遇到的问题,不但使我能够顺利地完成毕业设计,在专业知识上长进不少,而且为我树立了严谨治学和忘我工作的榜样;而邱老师帮我们审查图纸,耐心帮我们找出中间的点滴错误。在此对他们表示由衷的感谢。 许海峰 2008年4月24日 25 附录1 翻译原文及译文 Doc No: P0193-GP-01-1 Doc Name: Analysis of Manufacturing Process Data Using TM QUICK Technology Issue: 1 Data: 20 April ,2006 Name(Print) Signature Author: D.Clifton Reviewer: S.Turner 26 Table of Contents 1 Executive Summary .............................................................................................................. 29 1.1 Introdution ........................................................................................................................... 29 1.2 Techniques Employed .......................................................................................................... 29 1.3 Summary of Results ............................................................................................................. 29 1.4 Observations ......................................................................................................................... 30 2 Introdution............................................................................................................................. 31 2.1 Oxford BioSignals Limited ................................................................................................. 31 3 External References .............................................................................................................. 32 4 Glossary ................................................................................................................................. 32 5 Data Description.................................................................................................................... 32 5.1 Data types ............................................................................................................................. 32 5.2 Prior Experiment Knowledge ............................................................................................. 32 5.3 Test Description .................................................................................................................... 33 6 Pre-processing ....................................................................................................................... 34 6.1 Removal of Start/Stop Transients ....................................................................................... 34 6.2 Removal of Power Supply Signal ........................................................................................ 34 6.3 Frequency Transformation ................................................................................................. 34 7 Analysis I-Visualisation ........................................................................................................ 37 7.1 Visualisation of High-Dimensional Data ............................................................................ 37 7.2 Visualising 5-D Manufacturing Process Data ................................ 错误~未定义书签。13 7.3 Automatic Novelty Detection .......................................................... 错误~未定义书签。15 7.4 Conclusion of Analysis I-Visualisation ........................................... 错误~未定义书签。16 8 Analysis II-Signature Analysis ......................................................... 错误~未定义书签。17 8.1 Constructing Signatures .................................................................. 错误~未定义书签。17 8.2 Visualising Signatures ..................................................................... 错误~未定义书签。19 8.3 Conclusion of Analysis II-Signature Analysis ................................ 错误~未定义书签。23 9 Analysis III-Template Analysis ........................................................ 错误~未定义书签。24 9.1 Constructing a Template of Normality .......................................... 错误~未定义书签。24 9.2 Results of Novelty Detection Using Template Analysis ................. 错误~未定义书签。25 9.3 Conclusion of Analysis III-Template Analysis ............................... 错误~未定义书签。26 10 Analysis IV-None-linear Prediction ............................................. 错误~未定义书签。27 10.1 Neural Networks for On-Line Prediction ...................................... 错误~未定义书签。27 10.2 Results of Novelty Detection using Non-linear Prediction ............ 错误~未定义书签。27 10.3 Conclusion of Analysis IV-Non-linear Prediction.......................... 错误~未定义书签。28 11 Overall Conclusion............................................................................ 错误~未定义书签。29 11.1 Methodology ..................................................................................... 错误~未定义书签。29 11.2 Summary of Tesults ......................................................................... 错误~未定义书签。29 11.3 Future Work ..................................................................................... 错误~未定义书签。29 12 Appendix A-NeuroScale Visualisations ....................................... 错误~未定义书签。31 27 28 Table of Figures Figure 1- Test 90. From top to bottom: Ax, Ay, Az, AE, SP against time t(s) Figure 2- Power spectra for Test 19 after removal of 50Hz power supply contribution. The top plot shows a 3-D “landspace” plot of each spectrum. The bottom plot shows a “contour” plot of the same information, with increasing signal power shown as increasing colour from black to red Figure 3- Power spectra for Test 19 after removal of all spectral components beneath power threshold Figure 4- Az against time (in seconds) for Test 19,before removal of low-power frequency components Figure 5- Az against time (in seconds) for Test 19, after removal of low-power frequency components Figure 6- SP for an example test, showing three automatically-detecrmined states:S-drilling in (shown in green); S-drill-bit break-through and removal 12 (shown in red); S-retraction (shown in blue) 3 Figure 7- Example signature of variable plotted against operating-point y Figure 8- Power spectra for test 51, frequency (Hz) on the x-axis between [0 f/2] s uFigure 9- Average significant frequency f Figure 10- Visualisation of AE signatures for all tests Figure 11- Visualisation of Ax broadband signatures for all tests Figure 12- Visualisation of Ax average-frequency signatures for all tests Figure 13- Novelty detection using a template signature Figure 14- 29 1 Executive Summary 1.1 Introduction The purpose of this investigation conducted by Oxford BioSignals was to examine and determine the suitability of its techniques in analyzing data from an example manufacturing process. This report has been submitted to Rolls-Royce for the expressed of assessing Oxford BioSignals’ techniques with respect to monitoring the example process. The analysis conducted by Oxford BioSignals (OBS) was limited to a fixed timescale, a fixed set of challenge data for a single process (as provided by Rolls-Royce and Aachen university of Technology), with no prior domain knowledge, nor information of system failure . 1.2 Techniques Employed OBS used a number of analysis techniques given the limited timescales: I-Visualisation, and Cluster Analysis This powerful method allowed the evolution of the system state (fusing all available data types) to be visualised throughout the series of tests. This showed several distinct modes of operation during the series, highlighting major events observed within the data, later correlated with actual changes to the system’s operation by domain experts. Cluster analysis automatically detects which of these events may be considered to be “abnormal”, with respect to previously observed system behavior . II-Signature represents each test as a single point on a plot, allowing changes between tests to be easily identified. Abnormal tests are shown as outlying points, with normal tests forming a cluster. Modeling the normal behavior of several features selected from the provided data, this method showed that advance warning of system failure could be automatically detected using these features, as well as highlighting significant events within the life of the system. III-Template Analysis This method allows instantaneous sample-by –sample novelty detection, suitable for on-line implementation. Using a complementary approach to Signature Analysis, this method also models normal system behavior. Results confirmed the observation made using previous methods. IV-Neural network Predictor Similarly useful for on-line analysis, this method uses an automated predictor of system behaviour(a neural network predictor), in which previously identified events were confirmed, and further significant episodes were detected. 1.3 Summary of Results Early warning of system failure was independently identified by the various analysis methods employed. Several significant events during the life of the process were correlated with actual known events later revealed by system experts. Changes in sensor configurations are identified, and periods of system stability (in which tests are similar to one another) are highlighted. This report shall be used as the basis for further correlation of detected events against 30 actual occurrences within the life of the system, to be performed by Aachen University of Technology. 1.4 Observations Based on this limited study, OBS are confident that their techniques are applicable to condition monitoring of the example manufacturing process as follows: Evidence shows that automated detection of system novelty is possible, compared to its “normal” operation. Early warning of system distress may be provided, giving adequate time to take preventative maintenance actions such that system failure may be avoided. Provision “fleet-wide” analysis is possible using the techniques considered within this investigation. The involvement of domain knowledge from system experts alongside OBS engineers will be crucial in developing future implementations. While this “blind” analysis showed that OBS modelling techniques are appropriate for process monitoring, it is the coupling of domain knowledge with OBS modelling techniques that may provide optimal diagnostic and prognostic analysis. 31 2 Introduction 2.1 Oxford BioSignals Limited This document reports on the initial analysis conducted by Oxford BioSignals of manufacturing process challenge data provided by Rolls-Royce, in conjunction with Aachen University of Technology(AUT). Oxford BioSignals Limited(OBS) is a world-class provider of Acquisition, Data Fusion, Neural Networks and other Advanced Signal Processing techniques and solutions branded under the collective name QUICK Technology. This technology not only provides for health and quality assurance monitoring of the operational performance of equipment and plant. QUICK Technology has been extensively proven in the field of gas turbine monitoring with both on-line and off-line implementations at multiple levels: as a research tool, a test bed system, a ground support tool, an on-board monitoring system, an off-line analysis tool and a “fleet” manager. Many of the techniques employed by OBS may be described as novelty detection methods. This approach has a significant advantage over many traditional classification techniques in that it is not necessary to provide fault data to the system during development. Instead, providing a sufficiently comprehensive model of the condition can be identified automatically. As information is discovered regarding the causes of these deviations it is then possible to move from novelty detection to diagnosis, but the ability to identify previously unseen abnormalities is retained at all stages. 32 3 External References Accompanying documentation providing further information on the data sets is available in unnumbered documents. 4 Glossary AUT- Aachen University of Technology GMM- Gaussian Mixture Model MLP- Multi-Layer Perception OBS- Oxford BioSignals Ltd. 5 Data Description The following sections give a brief overview of the data set obtained by visual inspection of the data. 4.1 Data types The data provided were recorded over a number of tests. Each test consisted of a similar procedure, in which an automated drill unit moved towards a static metallic disk at a fixed velocity (“feed”), a hole was drilled in the disk at that same feed-rate. The following data streams were recorded during each test, each sampled at a rate of 20 KHz: 1 A– acceleration of the disk-mounting unit in the x-plane,x 1 A- acceleration of the disk-mounting unit in the y-plane, y 1 A- acceleration of the disk-mounting unit in the z-plane, z2 AE-RMS acoustic emission, 50-400 KHz, 3 SP-power delivered to the drill spindle. Tests considered in this investigation used three drill-prices (of identical product specification) as shown in Table 1. Table 1-Experiment Parameters by Test Drill Number Test Numbers Drill Rotation Rate Feed Rate 1 [12] 1700RPM 80 mm/min 2 [3127] 1700RPM 80 mm/min 3 [130194] 1700RPM 120mm/min Note that tests 16,54,128,129 were not provided, thus a series of 190 tests are analysed in this investigation. These 190 tests are labeled as shown in Table 2. Table 2 –Test indices used in this report against actual test numbers Test Indices Actual Test Number [115] [115] [1652] [1753] [53125] [55127] [126190] [130194] 4.2 Prior Experiment Knowledge 4.2.1 Normal Tests AUT indicated that tests [10110] could be considered “normal processes”. 4.2.2 AE Sensor Placement 33 AUT noted that the position of the acoustic emission sensor was altered prior to test 77, and was adjusted prior to subsequent tests. From inspection of AE data, it appears that AE measurements are consistent after test 84, and so: ?AE is assumed to be unusable for tests [176] –the sensor records only white noise; ?AE is assumed to be usable, but possibly abnormal, for tests [7783] –the sensor position is being adjusted, resulting in extreme variation in measurements; ?AE is assumed to be usable for tests [94190] –the sensor position is held constant during these tests. Thus, the range of tests assumed to be normal [10110] should be reduced to [84110] when AE is considered. 4.3 Test Description Data recorded for during a typical test are shown in Figure 1. The duration of this test is approximately t=51 seconds. This section uses this test to illustrate a typical process, as described by AUT. Drill power-on and power-off events may be seen at the start and end of the test as transient spikes in SP. The drill unit is then moved towards the static disk at the constant feed rata specified in Table 1, between t=12 and 27 seconds. This corresponds to approximately constant values of SP during that period, approximately zero AE, and very lowamplitude acceleration in x-,y-,and z- planes. At t=27 seconds, the drill makes contact with the static disk and begins to drill into the metal. This corresponds to a step-change in SP to a higher lever, staying approximately constant until t=38 seconds. During this time, AE increases significantly to a largely constant but non-zero value. The values Ax and Az increase throughout this drilling operation, while the value of Ay remains approximately zero (as it does throughout the test). At t=38 seconds, the tip of the drill-bit passes through the rear face of the disk. The value of SP increases until t=44 seconds. During this period, AE reaches correspondingly high values, while Ax and Az decrease in amplitude. At t=44 seconds, the direction of the drill unit is reversed, and the drill is retracted from the metal disk. Until t=46 seconds, the value of SP and AE decrease rapidly. A transient is observed in Ax and Az at t =44 seconds, with vibration amplitude decreasing until t=46 seconds. At t=46 seconds, the drill-bit has been completely retracted from the metal disk, and the unit continues to be withdrawn at the feed rate until the end of the test. The value of SP decreases during this period(noting the power-off transient at the very end of the test), while the values of all three acceleration channels and AE are approximately zero. 34 6 .Pre-processing 4.4 Removal of Start/Stop Transients Assuming that normal and abnormal system behaviour will be evident from data acquired during the drilling process, prior to analysis, each test was shortened by retaining only data between the start and stop events, shown as transients in SP. For example, for the test shown in Figure 1, this corresponds to retaining the period [1350] seconds. 4.5 Removal of Power Supply Signal The 50 Hz power supply appears with in each channel, and was removed prior to analysis by application of a band-stop filter with stop-band [4951] Hz. 4.6 Frequency Transformation Data for each test were divided into windows of 4096 points. A 4096-point FFT for was performed using data within each window, for Ax,Ay and Az channels. This corresponds to approximately 5 FFTs per second of data,similar to the QUICK system used in aerospace analysis, shown to provide sufficient resolution for identifying frequency-based events indicative of system abnormality. For the analyses performed in this investigation, all spectral components of Ax, Ay, and Ay occurring at frequency f with power Pf below some threshold Pf
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