資源目錄里展示的全都有，所見即所得。下載后全都有,請放心下載。原稿可自行編輯修改=【QQ：401339828 或11970985 有疑問可加】 畢業(yè)設計（論文）評閱教師評閱表 題　　目 注塑機尾板機械加工工藝規(guī)程及夾具設計 學生姓名 班級學號 專業(yè) 機械設計制造及其自動化 評閱 教師姓名 職稱 工作單位 評分內(nèi)容 具 體 要 求 總分 評分 開題情況 調(diào)研論證 能獨立查閱文獻資料及從事其他形式的調(diào)研，能較好地理解課題任務并提出實施方案，有分析整理各類信息并從中獲取新知識的能力。 10 外文翻譯 摘要及外文資料翻譯準確，文字流暢，符合規(guī)定內(nèi)容及字數(shù)要求。 10 設計質量 論證、分析、設計、計算、結構、建模、實驗正確合理。 35 創(chuàng)新 工作中有創(chuàng)新意識，有重大改進或獨特見解，有一定實用價值。 10 撰寫質量 結構嚴謹，文字通順，用語符合技術規(guī)范，圖表清楚，書寫格式規(guī)范，符合規(guī)定字數(shù)要求。 15 綜合能力 能綜合運用所學知識和技能發(fā)現(xiàn)與解決實際問題。 20 總評分 評閱教師 評閱意見 評閱成績 總評分ⅹ20% 評閱教師簽名 日期 畢業(yè)設計（論文）答辯及最終成績 評 定 表 系（公章）： 學生姓名 答辯 日期 課題名稱 注塑機尾板機械加工工藝規(guī)程及夾具設計 指導 教師 楊益梅 成 績 評 定 分值 評 定 小計 課題介紹 思路清晰，語言表達準確，概念清楚，論點正確，實驗方法科學，分析歸納合理，結論嚴謹，設計（論文）有應用價值。 30 答辯 表現(xiàn) 思維敏捷,回答問題有理論根據(jù)，基本概念清楚，主要問題回答準確大、深入,知識面寬。 必 答 題 40 自 由 提 問 30 合 計 100 答 辯 評 分 分值： 答辯小組長簽名： 答辯成績a： ×25％＝ 指導教師評分 分值： 指導教師評定成績b： ×50％＝ 評閱教師評分 分值： 評閱教師評定成績c： ×25％＝ 最終評定成績： 分數(shù)： 等級： 答辯委員會主任簽名： 年 月 日 說明：最終評定成績＝a+b+c，三個成績的百分比由各院、系自己確定，但應控制在給定標準的10％左右。 材 料 清 單 1.本文件夾文件：材料清單、答辯資格審查表、工序卡、過程卡、教師評閱表、教師審閱表、開題報告、設計說明書、外文翻譯、中期檢查表、設計任務書、最終成績評定表 2.CAD圖紙：零件圖-A0、毛坯圖-A1、夾具體-手繪、裝配圖-A0等 3.PROE圖：共25個零件、1個裝配、7張裝配截圖等 4.實體材料：實習報告、實習日記 5.光盤一張（含所有相關材料） 注：其中含有下劃線的只有電子文件，有底紋的只有實體材料。 畢業(yè)設計(論文)工作中期檢查表 題目 注塑機尾板機械加工工藝規(guī)程及夾具設計 學生姓名 專業(yè) 機械設計制造及其自動化 指 導 教 師 填 寫 學生開題情況 學生調(diào)研及查閱文獻情況 畢業(yè)設計（論文）原計劃有無調(diào)整 學生是否按計劃執(zhí)行工作進度 學生是否能獨立完成工作任務 學生的英文翻譯情況 學生每周接受指導的次數(shù)及時間 畢業(yè)設計（論文）過程檢查記錄情況 學生的工作態(tài)度在相應選項劃“√” □認真 □一般 □較差 尚存在的問題及采取的措施： 指導教師簽字： 年 月 日 系部意見： 負責人簽字： 年 月 日 畢業(yè)設計（論文）課題任務書 系： 機械工程系 專業(yè)： 機械制造與自動化 指導教師 學生姓名 課題名稱 注塑機尾板機械加工工藝規(guī)程及夾具設計 內(nèi)容及任務 一、設計依據(jù)及主要技術指標 1．注塑機尾板零件工作圖 2．生產(chǎn)綱領：中批生產(chǎn)（年產(chǎn)量為1000件） 3．工作制：單班制工作 二、設計內(nèi)容 1．分析零件工作圖樣，畫零件三維圖 2．確定毛坯種類、余量、形狀、并繪制毛坯-零件合圖 3．編制機械加工工藝規(guī)程一套（工序卡、工藝過程卡） 4．指定一主要工序設計專用夾具 5．研究設計要求，制定夾具定位夾緊方案 6．夾具總裝圖設計，畫三維及二維總裝圖 7．夾具精度校核 8．繪制夾具主要零件圖 9．編制設計說明書 三、設計任務： 1．工藝規(guī)程（包括工藝過程卡及主要工序工序卡）一套 2．零件--毛坯合圖，零件三維圖 3．三維及二維夾具裝配總圖 4．主要零件零件圖 5．設計說明書一份 擬達到的要求或技術指標 1．零件機加工工藝路線應設計多方案（至少２個），比較后選最佳方案； 2．應保證重要表面的加工質量與精度； 3．機床設備等選用，應考慮其經(jīng)濟性，宜采用通用機床和專用工夾具； 4．設計應以獨立完成為主，圖紙表達要正確清晰，計算正確，能借助各種工具書和技術資料獲得所需的正確數(shù)據(jù)； 5．同一課題組的專用夾具不得一樣； 6．材料牌號，形位公差，粗糙度，圖紙的標題欄及明細表都要采用新國標； 7．說明書應內(nèi)容完整，字跡工整，語言簡練，文字通順。說明書中應重點包括設計方案的分析與論證，考慮問題的出發(fā)點和最后選擇的依據(jù)，必要的計算過程，其他說明等 進度安排 起止日期 工作內(nèi)容 備注 畢業(yè)設計調(diào)研 畢業(yè)實習 畢業(yè)設計 答辯時間 主要參考資料 ［１］ 王先逵.機械制造工藝學[M].第二版.北京：機械工業(yè)出版社 2010.1 ［２］ 聯(lián)合編寫組.機械設計手冊 ［M］. 北京：化學工業(yè)出版社　1987.12 ［３］ 肖繼德，陳寧平.機床夾具設計［M］. 北京：機械工業(yè)出版社2005.3 ［４］ 李益民.機械制造工藝設計簡明手冊［M］北京：機械工業(yè)出版社.2005.7 ［５］ 王之櫟.機械設計綜合課程設計[M].第二版.北京：機械工業(yè)出版社 2009.7 ［６］ 孫麗媛.機械制造工藝及用夾具設計指導［M］. 北京：冶金工業(yè)出版社 2002.5 ［７］ 章躍.機械制造專業(yè)英語［M］. 北京：機械工業(yè)出版社2002.4 ［８］ 徐灝.機械設計手冊［M］. 北京：機械工業(yè)出版社　1991.9 ［９］ 楊叔子.機械加工工藝師手冊［M］. 北京：機械工業(yè)出版社2002.1 ［10］ 朱龍根.機械零件設計手冊［M］. 北京：機械工業(yè)出版社2005.8 ［11］ 四川大學研究所.機床夾具設計圖冊［M］. 北京：機械工業(yè)出版社2003.10 ［12］ 艾興、肖詩綱.切削用量簡明手冊 ［M］.北京：機械工業(yè)出版社 2004.1 ［16］ 上Internet網(wǎng)查找相關的設計資料，獲得的最新信息與權威資料 教研室 意見 年 月 日 院(系)主管領導意見 年 月 日 外 文 翻 譯 故障的分析、尺寸的決定以及凸輪的分析和應用 系 部： 機械工程系 學生姓名： 指導教師： 職 稱： 專 業(yè)： 班 級： 學 號： Failure Analysis，Dimensional Determination And Analysis，Applications Of Cams Abstract：It is absolutely essential that a design engineer know how and why parts fail so that reliable machines that require minimum maintenance can be designed；Cams are among the most versatile mechanisms available．A cam is a simple two-member device．The input member is the cam itself，while the output member is called the follower．Through the use of cams，a simple input motion can be modified into almost any conceivable output motion that is desired． Key words: failure high-speed cams design properties INTRODUCTION It is absolutely essential that a design engineer know how and why parts fail so that reliable machines that require minimum maintenance can be designed．Sometimes a failure can be serious，such as when a tire blows out on an automobile traveling at high speed．On the other hand，a failure may be no more than a nuisance．An example is the loosening of the radiator hose in an automobile cooling system．The consequence of this latter failure is usually the loss of some radiator coolant，a condition that is readily detected and corrected． The type of load a part absorbs is just as significant as the magnitude．Generally speaking，dynamic loads with direction reversals cause greater difficulty than static loads，and therefore，fatigue strength must be considered．Another concern is whether the material is ductile or brittle．For example，brittle materials are considered to be unacceptable where fatigue is involved． Many people mistakingly interpret the word failure to mean the actual breakage of a part．However，a design engineer must consider a broader understanding of what appreciable deformation occurs．A ductile material，however will deform a large amount prior to rupture．Excessive deformation，without fracture，may cause a machine to fail because the deformed part interferes with a moving second part．Therefore，a part fails(even if it has not physically broken)whenever it no longer fulfills its required function．Sometimes failure may be due to abnormal friction or vibration between two mating parts．Failure also may be due to a phenomenon called creep，which is the plastic flow of a material under load at elevated temperatures．In addition，the actual shape of a part may be responsible for failure．For example，stress concentrations due to sudden changes in contour must be taken into account．Evaluation of stress considerations is especially important when there are dynamic loads with direction reversals and the material is not very ductile． In general，the design engineer must consider all possible modes of failure，which include the following． ——Stress ——Deformation ——Wear ——Corrosion ——Vibration ——Environmental damage ——Loosening of fastening devices The part sizes and shapes selected also must take into account many dimensional factors that produce external load effects，such as geometric discontinuities，residual stresses due to forming of desired contours，and the application of interference fit joints． Cams are among the most versatile mechanisms available．A cam is a simple two-member device．The input member is the cam itself，while the output member is called the follower．Through the use of cams，a simple input motion can be modified into almost any conceivable output motion that is desired．Some of the common applications of cams are ——Camshaft and distributor shaft of automotive engine ——Production machine tools ——Automatic record players ——Printing machines ——Automatic washing machines ——Automatic dishwashers The contour of high-speed cams (cam speed in excess of 1000 rpm) must be determined mathematically．However，the vast majority of cams operate at low speeds(less than 500 rpm) or medium-speed cams can be determined graphically using a large-scale layout．In general，the greater the cam speed and output load，the greater must be the precision with which the cam contour is machined． DESIGN PROPERTIES OF MATERIALS The following design properties of materials are defined as they relate to the tensile test． Static Strength． The strength of a part is the maximum stress that the part can sustain without losing its ability to perform its required function．Thus the static strength may be considered to be approximately equal to the proportional limit，since no plastic deformation takes place and no damage theoretically is done to the material． Stiffness． Stiffness is the deformation-resisting property of a material．The slope of the modulus line and，hence，the modulus of elasticity are measures of the stiffness of a material． Resilience． Resilience is the property of a material that permits it to absorb energy without permanent deformation．The amount of energy absorbed is represented by the area underneath the stress-strain diagram within the elastic region． Toughness． Resilience and toughness are similar properties．However，toughness is the ability to absorb energy without rupture．Thus toughness is represented by the total area underneath the stress-strain diagram， as depicted in Figure 2．8b．Obviously，the toughness and resilience of brittle materials are very low and are approximately equal． Brittleness． A brittle material is one that ruptures before any appreciable plastic deformation takes place．Brittle materials are generally considered undesirable for machine components because they are unable to yield locally at locations of high stress because of geometric stress raisers such as shoulders，holes，notches，or keyways． Ductility． A ductility material exhibits a large amount of plastic deformation prior to rupture．Ductility is measured by the percent of area and percent elongation of a part loaded to rupture．A 5%elongation at rupture is considered to be the dividing line between ductile and brittle materials． Malleability． Malleability is essentially a measure of the compressive ductility of a material and，as such，is an important characteristic of metals that are to be rolled into sheets． Hardness． The hardness of a material is its ability to resist indentation or scratching．Generally speaking，the harder a material，the more brittle it is and，hence，the less resilient．Also，the ultimate strength of a material is roughly proportional to its hardness． Machinability． Machinability is a measure of the relative ease with which a material can be machined．In general，the harder the material，the more difficult it is to machine． COMPRESSION AND SHEAR STATIC STRENGTH In addition to the tensile tests，there are other types of static load testing that provide valuable information． Compression Testing． Most ductile materials have approximately the same properties in compression as in tension．The ultimate strength，however，can not be evaluated for compression．As a ductile specimen flows plastically in compression，the material bulges out，but there is no physical rupture as is the case in tension．Therefore，a ductile material fails in compression as a result of deformation，not stress． Shear Testing． Shafts，bolts，rivets，and welds are located in such a way that shear stresses are produced．A plot of the tensile test．The ultimate shearing strength is defined as the stress at which failure occurs．The ultimate strength in shear，however，does not equal the ultimate strength in tension．For example，in the case of steel，the ultimate shear strength is approximately 75% of the ultimate strength in tension．This difference must be taken into account when shear stresses are encountered in machine components． DYNAMIC LOADS An applied force that does not vary in any manner is called a static or steady load．It is also common practice to consider applied forces that seldom vary to be static loads．The force that is gradually applied during a tensile test is therefore a static load． On the other hand，forces that vary frequently in magnitude and direction are called dynamic loads．Dynamic loads can be subdivided to the following three categories． Varying Load． With varying loads，the magnitude changes，but the direction does not．For example，the load may produce high and low tensile stresses but no compressive stresses． Reversing Load． In this case，both the magnitude and direction change．These load reversals produce alternately varying tensile and compressive stresses that are commonly referred to as stress reversals． Shock Load． This type of load is due to impact．One example is an elevator dropping on a nest of springs at the bottom of a chute．The resulting maximum spring force can be many times greater than the weight of the elevator，The same type of shock load occurs in automobile springs when a tire hits a bump or hole in the road． FATIGUE FAILURE-THE ENDURANCE LIMIT DIAGRAM The test specimen in Figure 2.10a．，after a given number of stress reversals will experience a crack at the outer surface where the stress is greatest．The initial crack starts where the stress exceeds the strength of the grain on which it acts．This is usually where there is a small surface defect，such as a material flaw or a tiny scratch．As the number of cycles increases，the initial crack begins to propagate into a continuous series of cracks all around the periphery of the shaft．The conception of the initial crack is itself a stress concentration that accelerates the crack propagation phenomenon．Once the entire periphery becomes cracked，the cracks start to move toward the center of the shaft．Finally，when the remaining solid inner area becomes small enough，the stress exceeds the ultimate strength and the shaft suddenly breaks．Inspection of the break reveals a very interesting pattern，as shown in Figure 2.13．The outer annular area is relatively smooth because mating cracked surfaces had rubbed against each other．However，the center portion is rough，indicating a sudden rupture similar to that experienced with the fracture of brittle materials． This brings out an interesting fact．When actual machine parts fail as a result of static loads，they normally deform appreciably because of the ductility of the material. Thus many static failures can be avoided by making frequent visual observations and replacing all deformed parts．However，fatigue failures give to warning．Fatigue fail mated that over 90% of broken automobile parts have failed through fatigue． The fatigue strength of a material is its ability to resist the propagation of cracks under stress reversals．Endurance limit is a parameter used to measure the fatigue strength of a material．By definition，the endurance limit is the stress value below which an infinite number of cycles will not cause failure． Let us return our attention to the fatigue testing machine in Figure 2.9．The test is run as follows：A small weight is inserted and the motor is turned on．At failure of the test specimen，the counter registers the number of cycles N，and the corresponding maximum bending stress is calculated from Equation 2.5．The broken specimen is then replaced by an identical one，and an additional weight is inserted to increase the load．A new value of stress is calculated，and the procedure is repeated until failure requires only one complete cycle．A plot is then made of stress versus number of cycles to failure．Figure 2.14a shows the plot，which is called the endurance limit or S-N curve．Since it would take forever to achieve an infinite number of cycles，1 million cycles is used as a reference．Hence the endurance limit can be found from Figure 2.14a by noting that it is the stress level below which the material can sustain 1 million cycles without failure． The relationship depicted in Figure 2.14 is typical for steel，because the curve becomes horizontal as Napproaches a very large number．Thus the endurance limit equals the stress level where the curve approaches a horizontal tangent．Owing to the large number of cycles involved，N is usually plotted on a logarithmic scale，as shown in Figure 2.14b．When this is done，the endurance limit value can be readily detected by the horizontal straight line．For steel，the endurance limit equals approximately 50% of the ultimate strength．However，if the surface finish is not of polished equality，the value of the endurance limit will be lower．For example，for steel parts with a machined surface finish of 63 microinches ，the percentage drops to about 40%．For rough surfaces，the percentage may be as low as 25%． The most common type of fatigue is that due to bending．The next most frequent is torsion failure，whereas fatigue due to axial loads occurs very seldom．Spring materials are usually tested by applying variable shear stresses that alternate from zero to a maximum value，simulating the actual stress patterns． In the case of some nonferrous metals，the fatigue curve does not level off as the number of cycles becomes very large．This continuing toward zero stress means that a large number of stress reversals will cause failure regardless of how small the value of stress is．Such a material is said to have no endurance limit．For most nonferrous metals having an endurance limit，the value is about 25% of the ultimate strength． EFFECTS OF TEMPERATURE ON YIELD STRENGTH AND MODULUS OF ELASTICITY Generally speaking，when stating that a material possesses specified values of properties such as modulus of elasticity and yield strength，it is implied that these values exist at room temperature．At low or elevated temperatures，the properties of materials may be drastically different．For example，many metals are more brittle at low temperatures．In addition，the modulus of elasticity and yield strength deteriorate as the temperature increases．Figure 2.23 shows that the yield strength for mild steel is reduced by about 70% in going from room temperature to 1000oF． Figure 2.24 shows the reduction in the modulus of elasticity E for mild steel as the temperature increases．As can be seen from the graph，a 30% reduction in modulus of elasticity occurs in going from room temperature to 1000oF．In this figure，we also can see that a part loaded below the proportional limit at room temperature can be permanently deformed under the same load at elevated temperatures． CREEP: A PLASTIC PHENOMENON Temperature effects bring us to a phenomenon called creep，which is the increasing plastic deformation of a part under constant load as a function of time．Creep also occurs at room temperature，but the process is so slow that it rarely becomes significant during the expected life of the temperature is raised to 300oC or more，the increasing plastic deformation can become significant within a relatively short period of time．The creep strength of a material is its ability to resist creep，and creep strength data can be obtained by conducting long-time creep tests simulating actual part operating conditions．During the test，the plastic strain is monitored for given material at specified temperatures． Since creep is a plastic deformation phenomenon，the dimensions of a part experiencing creep are permanently altered．Thus，if a part operates with tight clearances，the design engineer must accurately predict the amount of creep that will occur during the life of the machine．Otherwise，problems such binding or interference can occur． Creep also can be a problem in the case where bolts are used to clamp tow parts together at elevated temperatures．The bolts，under tension，will creep as a function of time．Since the deformation is plastic，loss of clamping force will result in an undesirable loosening of the bolted joint．The extent of this particular phenomenon，called relaxation，can be determined by running appropriate creep strength tests． Figure 2.25 shows typical creep curves for three samples of a mild steel part under a constant tensile load．Notice that for the high-temperature case the creep tends to accelerate until the part fails．The time line in the graph (the x-axis) may represent a period of 10 years，the anticipated life of the product． SUMMARY The machine designer must understand the purpose of the static tensile strength test．This test determines a number of mechanical properties of metals that are used in design equations．Such terms as modulus of elasticity，proportional limit，yield strength，ultimate strength，resilience，and ductility define properties that can be determined from the tensile test． Dynamic loads are those which vary in magnitude and direction and may require an investigation of the machine part’s resistance to failure．Stress reversals may require that the allowable design stress be based on the endurance limit of the material rather than on the yield strength or ultimate strength． Stress concentration occurs at locations where a machine part changes size，such as a hole in a flat plate or a sudden change in width of a flat plate or a groove or fillet on a circular shaft．Note that for the case of a hole in a flat or bar，the value of the maximum stress becomes much larger in relation to the average stress as the size of the hole decreases．Methods of reducing the effect of stress concentration usually involve making the shape change more gradual． Machine parts are designed to operate at some allowable stress below the yield strength or ultimate strength．This approach is used to take care of such unknown factors as material property variations and residual stresses produced during manufacture and the fact that the equations used may be approximate rather that exact．The factor of safety is applied to the yield strength or the ultimate strength to determine the allowable stress． Temperature can affect the mechanical properties of metals．Increases in temperature may cause a metal to expand and creep and may reduce its yield strength and its modulus of elasticity．If most metals are not allowed to expand or contract with a change in temperature，then stresses are set up that may be added to the stresses from the load．This phenomenon is useful in assembling parts by means of interference fits．A hub or ring has an inside diameter slightly smaller than the mating shaft or post．The hub is then heated so that it expands enough to slip over the shaft．When it cools，it exerts a pressure on the shaft resulting in a strong frictional force that prevents loosening． 故障的分析、尺寸的決定以及凸輪的分析和應用 摘要：作為一名設計工程師有必要知道零件如何發(fā)生和為什么會發(fā)生故障，以便通過進行最低限度的維修以保證機器的可靠性；凸輪是被應用的最廣泛的機械結構之一，是一種僅僅有兩個組件構成的設備。主動件本身就是凸輪，而輸出件被稱為從動件。通過使用凸輪，一個簡單的輸入動作可以被修改成幾乎可以想像得到的任何輸出運動。 關鍵詞：故障 高速凸輪 設計屬性 前言介紹： 作為一名設計工程師有必要知道零件如何發(fā)生和為什么會發(fā)生故障，以便通過進行最低限度的維修以保證機器的可靠性。有時一次零件的故障或者失效可能是很嚴重的一件事情，比如，當一輛汽車正在高速行駛的時候，突然汽車的輪胎發(fā)生爆炸等。另一方面，一個零件發(fā)生故障也可能只是一件微不足道的小事，只是給你造成了一點小麻煩。一個例子是在一個汽車冷卻系統(tǒng)里的暖氣裝置軟管的松動。后者發(fā)生的這次故障造成的結果通常只不過是一些暖氣裝置里冷卻劑的損失，是一種很容易被發(fā)現(xiàn)并且被改正的情況。 能夠被零件進行吸收的載荷是相當重要的。一般說來，與靜載重相比較，有兩個相反方向的動載荷將會引起更大的問題，因此，疲勞強度必須被考慮。另一個關鍵是材料是可延展性的還是脆性的。例如，脆的材料被認為在存在疲勞的地方是不能夠被使用的。 很多人錯誤的把一個零件發(fā)生故障或者失效理解成這樣就意味著一個零件遭到了實際的物理破損。無論如何，一名設計工程師必須從一個更廣泛的范圍來考慮和理解變形是究竟如何發(fā)生的。一種具有延展性的材料，在破裂之前必將發(fā)生很大程度的變形。發(fā)生了過度的變形，但并沒有產(chǎn)生裂縫，也可能會引起一臺機器出毛病，因為發(fā)生畸變的零件會干擾下一個零件的移動。因此，每當它不能夠再履行它要求達到的性能的時候，一個零件就都算是被毀壞了（即使它的表面沒有被損毀）。有時故障可能是由于兩個兩個相互搭配的零件之間的不正常的磨擦或者異常的振動引起的。 故障也可能是由一種叫蠕變的現(xiàn)象引起的，這種現(xiàn)象是指金屬在高溫下時一種材料的塑性流動。此外，一個零件的實際形狀可能會引起故障的發(fā)生。例如，應力的集中可能就是由于輪廓的突然變化引起的，這一點也需要被考慮到。當有用兩個相反方向的動載荷，材料不具有很好的可延展性時，對應力考慮的評估就特別重要。 一般說來，設計工程師必須考慮故障可能發(fā)生的全部方式，包括如下一些方面： ——壓力 ——變形 ——磨損 ——腐蝕 ——振動 ——環(huán)境破壞 ——固定設備松動 在選擇零件的大小與形狀的時候，也必須考慮到一些可能會產(chǎn)生外部負載影響的空間因素，例如幾何學間斷性，為了達到要求的外形輪廓及使用相關的連接件，也會產(chǎn)生相應的殘余應力。 凸輪是被應用的最廣泛的機械結構之一，是一種僅僅有兩個組件構成的設備。主動件本身就是凸輪，而輸出件被稱為從動件。通過使用凸輪，一個簡單的輸入動作可以被修改成幾乎可以想象得到的任何輸出運動。常見的一些關于凸輪應用的例子有： ——凸輪軸和汽車發(fā)動機工程的裝配 ——專用機床 ——自動電唱機 ——印刷機 ——自動的洗衣機 ——自動的洗碗機 高速凸輪(凸輪超過1000 rpm的速度)的輪廓必須從數(shù)學意義上來定義。無論如何，大多數(shù)凸輪以低速(少于500 rpm)運行而中速的凸輪可以通過一個大比例的圖形表示出來。一般說來，凸輪的速度和輸出負載越大，凸輪的輪廓在被床上被加工時就一定要更加精密。 材料的設計屬性 當他們與抗拉的試驗有關時，材料的下列設計特性被定義如下。 靜強度：一個零件的強度是指零件在不會失去它被要求的能力的前提下能夠承受的最大應力。因此靜強度可以被認為是大約等于比例極限，從理論上來說，我們可以認為在這種情況下，材料沒有發(fā)生塑性變形和物理破壞。 剛度：剛度是指材料抵抗變形的一種屬性。這條斜的模數(shù)線以及彈性模數(shù)是一種衡量材料的剛度的一種方法。 彈性：彈性是指零件能夠吸收能量但并沒有發(fā)生永久變形的一種材料的屬性。吸收的能量的多少可以通過下面彈性區(qū)域內(nèi)的