【正文】 —loop system, the machine is positioned solely by stepping motor drives in response to mands by a is one basic type of NC or Positional Control In pointtopoint control the machine tool elements(tools, table, etc.)are moved to programmed locations and the machining operations performedafter the motions are path or speed of movement between locations is unimportant。 Machinery機(jī)械原理及機(jī)械設(shè)計(jì) Mechanical Designing機(jī)械原理及應(yīng)用 Mechanical Principle amp。 Electrical Transmission機(jī)電傳動(dòng)控制 Mechanical amp。 Signal Processing金屬工藝及設(shè)計(jì) Metal Technics amp。 Design機(jī)械工業(yè)企業(yè)管理 Mechanic Industrial Enterprise Management機(jī)械零件課程設(shè)計(jì) Course Design of Machinery Elements投資經(jīng)濟(jì)學(xué) Investment Economics現(xiàn)代企業(yè)管理 Modern Enterprise Administration市場營銷學(xué) Market Selling生產(chǎn)實(shí)習(xí)Production Practice課程設(shè)計(jì) Course Exercise有限元法 FInite Element金工實(shí)習(xí)Metalworking Practice液壓傳動(dòng) Hydraulic Transmission微機(jī)原理及接口技術(shù) Principle amp。 electrical Transmission Control機(jī)電耦合系統(tǒng) Mechanical amp。 Mechanical Applications機(jī)械原理課程設(shè)計(jì) Course Exercise of Mechanical Principle機(jī)械原理與機(jī)械零件 Mechanical Principle and Mechanical Elements機(jī)械原理與機(jī)械設(shè)計(jì) Mechanical Principle and Mechanical Design機(jī)械噪聲控制 Control of Mechanical Noise機(jī)械制造概論 Introduction to Mechanical Manufacture機(jī)械制造工藝學(xué) Technology of Mechanical Manufacture機(jī)械制造基礎(chǔ) Fundamental of Mechanical Manufacture機(jī)械制造基礎(chǔ)(金屬工藝學(xué))Fundamental Course of Mechanic Manufacturing(Meta機(jī)械制造系統(tǒng)自動(dòng)化 Automation of Mechanical Manufacture System機(jī)械制造中計(jì)算機(jī)控制 Computer Control in Mechanical Manufacture互換性與技術(shù)測量 Elementary Technology of Exchangeability Measurement焊接方法 Welding Method焊接方法及設(shè)備 Welding Method amp。only the coordinates of the end points of the motions are accurately type of control is suitable for drill presses and some boring machines, where drilling, tapping, or boring operations must be performed at various locations on the work or Linear Control StraightLine control systems are able to move the cutting tool parallel to one of the major axes of the machine tool at a controlled rate suitable for is normally only possible to move in one direction at a time, so angular cuts on the work piece are not possible, consequently, for milling machines, only rectangular configurations can be machined or for lathes only surfaces parallel or perpendicular to the spindle axis can be type of controlled motion is often referred to as linear control or a halfaxis of with this form of control are also capable of pointtopoint original N/C used the closed—loop the two systems, closed and open loop, closed loop is more accurate and, as a consequence, is generally more , open—loop systems were used almost entirely for lightduty applications because of inherent power limitations previously associated with conventional electric stepping advances in the development of electro hydraulic stepping motors have led to increasingly heavier machine load 數(shù)控技術(shù)數(shù)控是可編程自動(dòng)化技術(shù)的一種形式,通過數(shù)字、字母和其他符號來控制加工設(shè)備。數(shù)控機(jī)床有兩種基本形式：點(diǎn)位控制和連續(xù)控制(也稱為輪廓控制)。數(shù)據(jù)輸人裝置,也稱“人機(jī)聯(lián)系裝置”,可用人工或全自動(dòng)方法向機(jī)床提供數(shù)據(jù)。在大多數(shù)情況下,按鈕、開關(guān)和其他類似的旋鈕是數(shù)據(jù)輸入元件。每一個(gè)程序塊代表一種加工功能、一種操作或兩者的組合。此時(shí),操作者只是簡單地上、下工件。雖然紙帶上的數(shù)據(jù)是自動(dòng)進(jìn)給的,但實(shí)際編程卻是手工完成的,在編碼紙帶做好前,編程者經(jīng)常要和一個(gè)計(jì)劃人員或工藝工程師一起工作,選擇合適的數(shù)控機(jī)床,決定加工材料,計(jì)算切削速度和進(jìn)給速度,決定所需刀具類型,仔細(xì)閱讀零件圖上尺寸,定下合適的程序開始的零參考點(diǎn),然后寫出程序清單,其上記載有描述加工順序的編碼數(shù)控指令,機(jī)床按順序加工工件到圖樣要求。有些光電裝置能以高達(dá)每秒1000個(gè)字節(jié)的速度閱讀,這對保持機(jī)床連續(xù)動(dòng)作是必須的,否則,在輪廓加工時(shí),刀具可能在工件上產(chǎn)生劃痕。位置控制通過傳感器實(shí)現(xiàn),在實(shí)際工作時(shí),記錄下滑臺的位置,并將這些信息送回控制單元。對于一件事物,它被不連續(xù)直流電壓脈沖驅(qū)使,是來自數(shù)傳計(jì)算機(jī)和其他的自動(dòng)化的非常方便的輸出控制系統(tǒng)。這些申請的大部分是公開環(huán) ,但是雇用回應(yīng)環(huán)檢測受到驅(qū)策的成份位置是可能的。出現(xiàn)誤動(dòng)作時(shí),控制單元繼續(xù)發(fā)出電脈沖。最初的數(shù)控系統(tǒng)采用開環(huán)系統(tǒng)。ren Andersson(KTH), and Br229。rssinen are highly contributionsto this work by colleagues at Volvo are gratefully INTRODUCTION Background Noise is increasingly considered an environmental belief is reflected in demands for lower noise levels in many areas of society, including the working spend a lot of time in this environment and noise can lead not only to hearing impairment but also to decreased ability to concentrate, resulting in decreased productivity and an increased risk of , too, has bee increasingly quality of a product can be defined as its ability to fulfill customers’ demands often change over time, and the best petitors in the market will set the concerns are also expressed in relation to construction machinery such as wheel loaders and articulated gearbox is sometimes the dominant source of noise in these if the gear noise is not the loudest source, its pure high frequency tone is easily distinguished from other noise sources and is often perceived as noise creates an impression of poor order not to be heard, gear noise must be at least 15 dB lower than other noise sources, such as engine Gear noise This dissertation deals with the kind of gearbox noise that is generated by gears under noise is often referred to as “gear whine” and consists mainly of pure tones at high frequencies corresponding to the gear mesh frequency and multiples thereof, which are known as tone with the same frequency as the gear mesh frequency is designated the gear mesh harmonic, a tone with a frequency twice the gear mesh frequency is designated the second harmonic, and so term “gear mesh harmonics” refers to all multiples of the gear mesh error(TE)is considered an important excitation mechanism for gear [1] defines transmission error as “the difference betweenthe actual position of the output gear and the position it would occupy if the gear drive were perfectly conjugate.” Transmission error may be expressed as angular displacement or as linear displacement at the pitch error is caused by deflections, geometric errors, and geometric addition to gear whine, other possible noisegenerating mechanisms in gearboxes include gear rattle from gears running against each other without load, and noise generated by the case of automatic gearboxes, noise can also be generated by internal oil pumps and by of these mechanisms are dealt with in this work, and from now on “gear noise” or “gearbox noise” refers to “gear whine”.MackAldener [2] describes the noise generation process from a gearbox as consisting of three parts: exci