【正文】 如果超過 6點(diǎn)藝術(shù)使用 ,附加分將盈余和不必要的 ,因此會(huì)是多余的約束。測(cè)試三自由度是逮捕三個(gè)外部力量通常提供了直接由夾緊。 The bane of the ponent is resting on three locating pins which is the minimum number of points upon which it will foxily seat. 該組件的克星放在三定位銷是最少數(shù)量的點(diǎn)上 ,它將 foxily 座位。這可以通過六個(gè)在身體的案例顯示在圖 8 1,這被稱為六點(diǎn)定位原理。 YY 或者工業(yè)區(qū) ,所以它有 6 個(gè)自由度的旋轉(zhuǎn)和六個(gè)自由翻譯 [2]。 TM Location of The Workpiece TM 位置的工件 A body that is pletely free in space has twelve degrees of freedom shown in . 身體是完全免費(fèi)的空間有十二個(gè)自由度顯示在圖 8 l。 Cost reduction. Higher production rate, reduction in scarp, easy assembly and savings in labor costs result in substantial reduction in the cost of workpieces produced with jigs and fixtures. 降低成本。 There is no need for skillful setting of the workpiece of tool. Any average person can be trained to use jigs and fixtures, the replacement of a skilled workman with unskilled labor can effect substantial saving in labor cost. 不需要熟練的設(shè)置的 工件的工具。工裝夾具定位和夾緊的簡(jiǎn)化工件。沒有必要選擇裝配。 Interchangeability. Jigs and futures facilitate uniform quality in manufacture. There is no need for selective assembly. Any part of machine fits properly in assembly and all similar ponents are interchangeable 可交換性。 Advantages of Jigs and Fixtures 工裝夾具的優(yōu)點(diǎn) Productivity. Jigs and fixtures eliminate individual marking, positioning and frequent checking, which reduces operation time and increase productivity. 生產(chǎn)力。他們直接工具 c 站立位的 工件。裝置通常用于加工 (銑床、規(guī)劃、塑造和轉(zhuǎn)動(dòng) ,等等 )和其他制造業(yè)務(wù) ,如焊接、熱處理、機(jī)械加工檢驗(yàn)和組裝等。它必須正確定位一個(gè)工件在給定的取向?qū)Φ毒呋驕y(cè)量設(shè)備 ,或?qū)α硪粋€(gè)組件 ,比如在大會(huì)。 [11 生產(chǎn)設(shè)備通常 workholders 與 /沒有工具指導(dǎo) /設(shè)置安排這些被稱為工裝夾具。這是一個(gè)符合 (取決于實(shí)際大小的孔、軸 )兩個(gè)間隙和干擾可能發(fā)生耦合。大小上限的樹干是較小的或者至少等于下限大小的軸。 Interference fit. It is a fit always ensuring some interference between the hole and shaft in the coupling. The upper limit size of the bole is smaller or at least equal to the lower limit size of the shaft. 干涉配合。這是一個(gè)適合啟用一個(gè)間隙孔和軸的耦合。 Fit is the general range of tightness resulting from the application of a specific bination of allowance and tolerances in the design of mating parts. 配合是一般的一系列緊張?jiān)斐傻奶囟ńM合的應(yīng)用的津貼和公差設(shè)計(jì)的配件。 Unilateral tolerance expression has the advantage that they are easier to check on drawings and that the change in the tolerance can be made with the least disturbance to other dimensions. 單邊公差表達(dá)式的優(yōu)勢(shì)在于 ,他們更容易檢查圖紙 ,寬容的變化可以用最少的干擾到其他維度?！斑@個(gè)表達(dá)式。例子是 2。 For this expression. the dimension of the part would be permitted to vary between and for a total tolerance of . 單方面的公差。正負(fù)局限結(jié)合起來 form a single value.[5J 形成一個(gè)單一值。對(duì)于這個(gè)表達(dá)式 ,該維度的部分將被允許在 和 之間不同共 的容忍。一個(gè)雙邊公差是一個(gè)寬容的變化是不被允許在兩個(gè)方向上從一個(gè)指定的尺寸。 Tolerances can be expressed in either of two ways. 公差可表示成兩種方式中的任何一個(gè)。故意差別最大材料限制的配件。例如 ,一個(gè)孔尺寸作為 ,因此上偏差是 + 和更低的偏差為 。 Deviations. The upper and lower deviations obtained by subtracting basic size from limit size. For example, a hole dimensioned as , thus upper deviation is + and lower deviation is . 偏差。實(shí)際大小。 499(上限 )和 (下限 ),圖 7 所示。 (4 j(見圖 7 ia) imit size. It includes upper limit size and lower limit size which are allowable extreme sizes of a part Fox example, the limits for a hole arc 1500 (lower limit) and (upper limit) and for a shaft I . 499 (upper limit) and (lower limit), shown in . I b. Actual size. It is the measured size of the finished part, shown in 模仿的大小。這是一個(gè)精確的理論大小的部分限制尺寸計(jì)算。 Nominal size (basic size). It is the designation used for general identification and usually expressed in mon fractions. It is an exact theoretical size of a part from which limit dimensions are puted. The nominal size of a part should be selected from the preferred dimension series indicated by the national standard. (4J (shown in ) 公稱尺寸 (基本的大小 )。間隙 ,干擾 ,或過渡配合引用的對(duì)象如何適合一個(gè)裝配。 [3]合適的質(zhì)量特征是津貼值。 Allowance. The difference between the largest allowable shaft size and the smallest hole diameter is termed as the allowance. [3] The quality of the fit is characterized by the allowance value. 津貼。 Size. The size of an object or its mate is (mown as nominal, basic, or design size. 大小。理解公差 ,你應(yīng)該了解一些相關(guān)的定義的確定公差。 Tolerances 公差 Tolerance is the total amount that a specific dimension is permitted to vary. It is the difference between the maximum and the minimum limits for the dimension. To understand tolerances, you should understand some of the definitions associated with the determination of a tolerance. These definitions may be generally categorized as relating to size, allowance, or fit. 寬容是一個(gè)特定的總量維度是允許不同。校長(zhǎng)因子用于設(shè)置一個(gè)容忍一個(gè)維度應(yīng)該函數(shù)的特性被控制的維度。所需的精確度上給定的部分是然后給出的尺寸公差 ,按照?qǐng)D紙。事實(shí)上 ,這是沒有必要的或有用的。表面粗糙度的偏差。位置偏差 。 3. Position deviations。 2。尺寸偏差 。偏離實(shí)際的表面分為四組 ,使評(píng)估、處 方和檢查錯(cuò)誤的允許生產(chǎn)過程中 : 1. Dimensional deviations。日常生產(chǎn)過程不允許維護(hù) (或測(cè)量 )給定的幾何屬性以絕對(duì)的精度。大多數(shù)維度有不同程度的準(zhǔn)確性和一種方式來指定可接受的限制在維方差這樣一個(gè)人造的部分會(huì)被接受 ,還是函數(shù)。維度上給出的部分設(shè)計(jì)圖和制造這些維度應(yīng)該完全一樣 ,恰到好處。 An engineering drawing must be properly dimensioned in order to convey the designer39。隨著準(zhǔn)確性或更少的變異在尺寸、勞動(dòng)和機(jī)械需要制造一個(gè)部分是更多的成本密集型。 Interchangeable parts require a high degree of accuracy to fit together. With increasing accuracy or less variation in the dimension, the labor and machinery required to manufacture a part is more cost intensive. [l] Any manufacturer should have a thorough knowledge of the tolerances to increase the quality and reliability of 39。這個(gè)差距只有幾英寸的秒這個(gè)級(jí)別 ,這是維持在一個(gè)恒定值由伺服機(jī)構(gòu) ,促動(dòng)和控制工具進(jìn)給。當(dāng)潛在的區(qū)別和工件的電極是足夠高 ,電介質(zhì)分解和瞬時(shí)放電通過電介質(zhì) ,消除少量的材料從工件表面。這個(gè)高電壓產(chǎn)生電場(chǎng)在絕緣介質(zhì)中存在的差距和工件之間的狹窄電極。圖 6 所示。所以 ,硬度的材料不再是一個(gè)主要因素電火花放電加工。主要的吸引力比傳統(tǒng)的電火花加工過程 ,如金屬切削使用不同的工具和磨削是這種技術(shù)利用熱電過程侵蝕無用的材料工件的一系列迅速反復(fù)出現(xiàn)的離散 電火花工件和電極之間。 Electrical Discharge Machining (EDM) 電火花加工 (EDM) Electrical discharge machining (EDM) sometimes is colloquially referred to as spark machining, spark eroding, burning, die sinking or wire erosion. It is one of the most widely used nontraditional machining processes. The main attraction of EDM over traditional machining processes such as metal cutting using different tools and grinding is that this technique utilizes thermoelectric process to erode un