圓柱齒輪公差與檢測.ppt

第7章 圓柱齒輪公差與配合應用Chapter 7 Cylindrical gears tolerance and fit application,基本要求 Basic requirements,目的：了解圓柱齒輪的公差標準 Aim:To understand tolerance standards of Cylindrical gear 初步掌握： Grasp preliminarily: 1.應用要求、加工誤差 Application requirements and manufacturing error 2.評定指標 Evaluation index 3.圖樣標注 Labels of pattern 4.齒輪精度設計 Design of gear accuracy 操作技能：評定指標的檢驗 Manipulative skill:The test of evaluation index.,特點 Traits 1 結構緊湊 Compact structure 2 恒定的傳動比 Constant transmission ratio 3 傳動效率高 High transmission efficiency 4 可實現平行軸、相交軸和交錯軸之間的傳動 It could realize the transmission between parallel axles, intersectant axles and interlaced axles 5 使用壽命長 Long working life 6 維護保養(yǎng)簡單 Sample to maintain,作用：傳遞空間任意兩軸（平行、相交、交錯）的旋轉運動，或將轉動轉換為移動。Founction:To transmit the revolving movements of any two axles(parallel,intersectant and interlaced) in space.And to convert turn to shift.,缺點：要求較高的制造和安裝精度，加工成本高、不適宜遠距離傳動。 Disadvantages:It needs higher accuracies of manufacture and installment. Conversion cost is high and it is not suitable for long distance transmission.,齒輪傳動的類型 Types of gear drive,傳動齒輪：轉速較高，功率較大 （汽車 飛機等變速裝置） Drive gear:Higher rotation rate and power(Speed variators in automobiles and airplanes) 動力齒輪：轉速不高，傳遞扭矩（礦山機械 起重機械） Power gear:The speed of revolution is not high and it transmits torque(mining machine and hoisting machinery) 分度齒輪：精確回轉（精密機床 儀表中的分度裝置） Dividing gear:Precise rotation(precision machine tool and dividing device in instrumentation),齒輪傳動機構組成 The form of gear transimission mechanism,齒輪副、軸、軸承、箱體pair of gears, axles, bearings and boxes,失效形式 failure mode,輪齒折斷 tooth breakage,1.由于多次重復的彎曲應力和應力集中造成的疲勞折斷；The fatigue fracture which is caused by oft-repeated bending stresses and stress concentration. 2.由于突然嚴重過載或沖擊載荷作用引起的過載折斷。The overload break which is caused by sudden severe overload or impact load. 直齒輪：齒寬較小的往往發(fā)生全齒折斷,齒寬較大的直齒輪或斜齒輪則容易發(fā)生局部折斷。 Straight gear:The gears with smaller breadth of tooth often emerge whole tooth fracture while the straight gears or helical gears with bigger breadth of tooth are easy to emerge local break.,一、 輪齒的失效形式,失效形式,齒面點蝕 Tooth surface pitting,原因：由于在齒面嚙合處脈動循環(huán)變接觸應力長期作用下，當應力峰值超過材料的接觸疲勞極限，經過一定應力循環(huán)次數后，先在節(jié)線附近的齒廓表面產生細微的疲勞裂紋。隨著裂紋的擴展，將導致小塊金屬剝落，產生齒面點蝕。Reason:Because of the long term effect of pulsating cyclic variable contact stress on meshing point of tooth surface.When peak stress exceeds materials contact fatigue limit, hairlike fatigue cracks will appear on tooth profile surface around nodel line after certain number of times of stress cycle.With the extending of flaws. Scrap metal will peel off to produce tooth surface pitting. 點蝕不良影響：影響輪齒正常嚙合，引起沖擊和噪聲，造成傳動的不平穩(wěn)。 Harmful effects of pitting:Influencing the normal engagement of gear teeth,causing concussions and noise,creating un-stationary transmission.,一、 輪齒的失效形式,失效形式,齒面膠合 Tooth surface bonding,高速重載傳動中，常因嚙合區(qū)溫度升高而引起潤滑失效，致使齒面金屬直接接觸而相互粘連。當齒面相對滑動時，較軟的齒面沿滑動方向被撕下而形成溝紋。On high speed and heavy load transmission.The raise of meshing zones temperature usually causes lubrication losing efficacy to lead to the direct contacts of tooth surface metal and adhesions of each other.When tooth surfaces slither relatively, softer tooth surfaces are torn-out on glide direction to form grooves.,傳動精度 transmission accuracy 齒側間隙-齒輪副合理性 backlash in circular tooth-The rationality of gear pairs.,1-1.齒輪的應用要求 Application requirements of gears,7.1 應用要求及加工誤差 Application requirements and processing errors,傳遞運動的準確性 The accuracy of transfer motion 傳遞運動的平穩(wěn)性 The stability of transfer motion 載荷分布的均勻性 The homogeneity of load distribution,要求從動輪與主動輪運動協調，應限制齒輪一轉內傳動比的不均勻性。Requiring the coordination of driven wheel and action wheels movement.We are supposed to restrict the uneven movements of gears in one round.,1.傳遞運動的準確性 The accuracy of transfer motions.,要求:齒輪在轉過一個齒距角的范圍內，其最大轉角誤差應限制在一定的范圍內。 Requirement:The maximum angular error should be restricted in a certain range within the range of that gear turning around one angular pitch. 一個齒距角內瞬時傳動比沖擊、振動和噪聲 Instantaneous transmission ratio within one angular pitchconcussion, shake and noise.,2.傳動的平穩(wěn)性 The stability of transfer motion,3.載荷分布的均勻性 The homogeneity of load distribution,輪齒嚙合過程中，工作齒面沿全齒高和全齒長上保持均勻接觸，并且接觸面積盡可能的大。In the engagement process of gear teeth.Working flanks of teeth are kept in even contact on whole teeth height and whole teeth length and contact areas should be as bigger as possible.,引起應力集中，造成局部磨損，輪齒折斷，影響齒輪的使用壽命 Causing stress concentration to lead to concentrated wear and tooth breakage so that influencing working lifes of gears.,齒輪傳動過程中，非接觸面之間一定要有合理的間隙。There must be reasonable clearance between non-contact surface in the process of gear transmission.,4.齒輪副側隙的合理性 Rationalities of backlashes of gear pairs,1.貯存潤滑油 store up lubricating oil 2.補償齒輪的變形 compensate the distortions of gears 3.制造和安裝誤差所引起的尺寸變動 size changes which are caused by Manufacturing and installation errors,不同齒輪的傳動精度要求 Transmission accuracy requirements of different gears,加工方法：rocessing methods: 按齒廓形成原理 仿形法 According to tooth profiles forming principlesform cutting method 展成法 generating method,7.2 加工誤差的來源與分類 The origins and classifications of mismachining tolerance,滾齒機 hobbing machine,誤差來源 Sources of errors,工藝系統(tǒng)：機床、夾具、刀具、齒坯本身 Process system:machine tool, fixture, cutter and gear blanks themselves.,安裝、調整 Install and adjust,1 幾何偏心 ej Geometric eccentricity,1 齒輪加工誤差來源 The sources of errors in gear machining,2 運動偏心ey ek +分度蝸輪加工誤差 Eccentric motion ey ek +mismachining tolerances of dividing worm wheel,1分度蝸輪dividing worm wheel 2 蝸桿worm 3 滾刀hobbing cutter 4 齒坯gear blanks,Gears with eccentric motions,3 機床傳動鏈的高頻誤差 High frequency errors of Machine tool transmission chains,原因：分度蝸桿的安裝偏心和軸向躥動,導致蝸輪（齒坯）轉速不均勻 Reasons:The installation eccentricities and axial drifting of indexing worms contribute to inhomogeneous speeds of worm gears(gear blanks). 結果：加工出的齒輪有齒距偏差和齒形偏差 Results:Processed gears have pitch deviations and profile deviations.,4滾刀的安裝誤差和加工誤差Installation errors and mismachining tolerances of hobbing cutters,滾刀偏心 ed Eccentricity of hobbing cutter,2.齒輪加工誤差的分類The classifications of gear machining errors, 按表現特征可分為4類：It could be divided into four classes acording to performance characteristic,齒廓誤差 齒距誤差 Tooth profile error Pitch error 齒向誤差 齒厚偏差 Tooth alignment error Tooth thickness deviation,齒廓相對于工件的旋轉中心分布不均勻 Tooth profile is irregularly distributed to rotating center of the workpiece.,齒廓不是理論的漸開線 Tooth profile is not theoretical involute.,齒面沿齒輪軸線方向的形狀和位置誤差 Tooth flanks form and position errors along gear axis.,齒厚相對于理論值在整個齒圈上不一致 Tooth thicknesss inconformity to theoretical value on whole gear ring., 按方向特征可分為3類 It could be divided into three classes according to directional features.,徑向誤差 切向誤差 軸向誤差 Radial errors Tangential errors Axial errors,齒高方向 齒厚方向 齒向方向 Tooth height direction Tooth thickness direction Direction of tooth, , 按周期或頻率特征可分 According to cycle or frequency characteristic,it could divided into,長周期誤差 Long cycle error,短周期誤差 Short cycle error,傳遞運動的準確性 The accuracy of transfer motion,工作平穩(wěn)性 Work stability,以齒輪一轉為周期 Regard gears one turn as cycle,以齒輪一齒為周期 Regard gears one tooth as cycle,圓柱齒輪傳動公差 Transmission tolerances of cylindrical gears,GB/T10095.1-2001GB/T10095.2-2001,傳遞運動準確性的評定指標 The evaluation indexes of transfer motion accuracy 傳遞運動平穩(wěn)性的評定指標 The evaluation indexes of transfer motion stability 載荷分布均勻性的評定指標 The evaluation indexes of load distribution homogeneity 影響側隙的單個齒輪因素 Single gear factor which influences sideshake,7.3 單個齒輪的評定指標 The evaluation criteria of single gear,-1 傳遞運動準確性的檢測項目The inspection items of transfer motion accuracy,切向綜合總偏差（F i） Tangential general deviation 齒距累積總偏差（Fp） Cumulative pitch error 徑向跳動（Fr） Radial runout 徑向綜合總偏差（Fi） Radical general deviation 公法線長度變動（Fw）The changes of base tangent length,單項評定指標 Single evaluation index,齒輪一轉范圍內，測頭在齒槽內與齒高中部雙面接觸，測頭相對于齒輪軸線的最大變動量稱齒圈徑向跳動。Within gears one turn range, gauge head is contacted in double sides with tooth height middle part within tooth space.The maximum variation that gauge contains toward gear axis is called gear ring radical runout.,Fr主要反映由于齒坯偏心引起的齒輪徑向長周期誤差。Fr mainly reflects the gear radical long term error which is caused by the eccentricity of gear blanks 可用齒圈徑向跳動檢查儀測量，測頭可以用球形或錐形。 It could tested by gear ring radical runout detector. Gauge head could use sphere or taper.,-2 傳動工作平穩(wěn)性的檢測項目 The inspection items of driving work stability,一齒切向綜合偏差 f i Tooth tangential and general deviation 一齒徑向綜合偏差 f i Tooth radical and general deviation 齒廓偏差 Tooth profile deviation 基圓齒距偏差 fpb Base circle pitch deviation 單個齒距偏差 fpt Single pitch deviation,-3 載荷分布均勻性的檢測項目 The inspection items of load distributions homogeneity,螺旋線偏差：在端面基圓切線方向上測得的實際螺旋線偏離設計螺旋線的量 Helix deviation:The tested amount that actual helix deviates from designed helix on the tangential direction of end face base circle. （1） 螺旋線總偏差F 在計值范圍內，包容實際螺旋線跡線的兩條設計螺旋線跡線間的距離Helix total deviation F Within the range of values,the distances between two designed helix path lines which include helix path lines. （2） 螺旋線形狀偏差 ff 在計值范圍內，包容實際螺旋線跡線的兩條與平均螺旋線跡線完全相同曲線間的距離 Helix shape deviation ff Within the range of values,the distances between two curves which are same as average helix path lines and including actual helix path lines. （3） 螺旋線傾斜偏差fh 在計值范圍的兩端與平均螺旋跡線相交的設計螺旋線跡線間的距離 Helix incline deviation fh Within the range of values,the distances between designed helix path lines that both ends are intersectant with average helix path lines.,-4 影響側隙的單個齒輪因素 Single gear factors that influence sideshakes,1 齒厚偏差fSnTooth thickness deviation齒厚的上偏差（ESnS）The upper deviation of tooth thickness 下偏差（ESni）Lower deviation,一般都為負值 Commonly to be negative value,2 公法線長度偏差 Base tangent length deviation,7.4 齒輪副評定指標 The evaluation indexes of gear pairs,1 軸線的平行度誤差 The parallelism errors of axes 2 中心距偏差 The deviations of centre-to-centre separations 3 接觸斑點 Contact spot 4 齒輪副的側隙 The sideshake of gear pair,4 齒輪副側隙 The sideshake of gear pair,齒輪副的最小極限側隙應根據齒輪工作時的溫度和潤滑條件確定，與齒輪的精度等級無關。The minimum limit sideshake of gear pair should be ascertained by gears working temperature and lubrication condition.It has nothing to do with the gears accuracy class.,高溫工作的傳動齒輪，為保證正常潤滑，避免發(fā)熱卡死，要求有較大的側隙；There should be biggish sideshake for drive gear working in high terperature.That is to ensure normal lubrication and preventing the gear from fever and jammed 而需正反轉或讀數機構的齒輪，為避免空程，則要求較小的側隙。There should be lesser sideshake for the gears to prevent idle stroke which need positive inversion or reading mechanism., 側隙獲得方法 The methods to obtain sideshake,1.基齒厚制:即固定齒厚的極限偏差，通過改變中心距的基本偏差來獲得不同的最小極限側隙，此方法用于中心距可調的機構。Base gear thickness:Fix gear thicknesss limit deviations.Obtaining different minimum limit side gaps through changing the basic deviations of centre-to-centre separations. This method is used for the mechanisms of which centre-to-centre separations are tunable. 2.基中心距制:即固定中心距的極限偏差，通過改變齒厚的上下偏差來得到不同的最小極限側隙，國標采用后一種. Base centre-to-centre separation distance system:Fix centre-to-centre separations limit deviation.Obtaining different minimum limit side gaps through changing the upper and lower deviations of gear thickness. Chinese Standard adopts the latter.,jbnmin,jbnmin = jbn1 + jbn2,工作溫度 潤滑方式 圓周速度 Working temperature Lubrication method Peripheral speed,補償溫升引起的變形Compensate the distortions caused by temperature rise,保證齒輪工作面的正常潤滑 Ensure the normal lubrication on gears working surface,最小法向極限側隙 The minimum limit sideshake on normal,Jbn2取決于潤滑方式和齒輪工作的圓周速度Jbn2 lies on lubricating method and the working peripheral speed of gear,7.5 漸開線圓柱齒輪精度設計 The precision design of involute cylindrical gear,齒輪精度等級的確定 The ascertainment of gears accuracy class 齒輪副側隙、齒厚極限偏差的確定 The ascertainment of backlash of gear pair and limit deviation of tooth thickness 齒坯精度和齒輪表面粗糙度 Precision of gear blanks and roughness of gear surfaces 圖樣標注 Pattern annotation,GB/T 10095.1-2001 漸開線圓柱齒輪精度第1部分 輪齒同側齒面偏差的定義和允許值The accuracy of involute cylindrical gear Part1 The definitions and allowable values of tooth flank tooth surface deviations GB/T 10095.2-2001 漸開線圓柱齒輪 精度第2部分 徑向綜合偏差與徑向跳動的定義和允許值The accuracy of involute cylindrical gear Part2 The definitions and allowable values of radial integrated deviations and radial runout GB/Z 18620.14 指導性技術文件 Technical guidance document,分度圓直徑：510000mm standard pitch diameter 法向模數：0.570mm normal modulus 齒寬：41000mm tooth width,標準適用范圍 The scope of applications for standards,13個精度等級 Thirteen accuracy classes 0 、1 、2 3 5 6 8 9 12,待用inactive,高精度等級 High accuracy classes,中等精度等級 Middle accuracy classes,最低精度等級The lowest accuracy classes,7 GB/T10095.2（1）2001,一、漸開線圓柱齒輪精度等級 The accuracy classes for involute cylindrical gears,1.齒輪精度等級的選擇 The selection for gear precision grade,根據用途、使用要求、傳遞功率、圓周速度及其它技術要求而定，同時考慮切齒工藝及經濟性。According to applications, operating requirements, transmitted power, peripheral speed and other technical requirements thus thinking about cutting process and economy.,選擇原則 Selection principles,選擇方法 Selection methods,1）計算法 computation technique 依據齒輪傳動用途的主要要求，計算確定出其中一種使用要求的精度等級，再按其他方面要求，作適當協調，來確定其它使用要求的精度等級.According to the main requirements of gear drive applications,calculating and ascertaining one usage requirements accuracy class.Then according to other requirements of other aspects and making proper coordination to ascertain the accuracy classes of other usage requirements.,當對傳遞運動準確性沒有特別要求時，第公差組的精度常比第公差組低一個等級。When there are no special requirements for the accuracy of transfer motion.The precision accuracy of No.1 Tolerance group is usually lower by one class to No.2 Tolerance group 當所傳遞的功率不特別大時，第公差組一般采用和第公差組相同的精度等級。When the transmission power is not very high. No.3 Tolerance group usually adopts the same accuracy classes as No.2 Tolerance group. 齒輪副中兩齒輪對應公差組的精度采用同級，也允許不同級。The corresponding tolerance groups that are of two gears in gear pairs also adopt different classes.,齒輪圓周線速度第公差組的精度等級 Gears circumferential line velocity The accuracy classes of No.2 Tolerance group,No.1 Tolerance group,No.2 Tolerance group,No.3 Tolerance group,The accuracies of transfer motions,The stabilities of transmissions,The homogeneities of load distributions,2）類比法 The methods of analogue 依據以往產品設計、性能試驗以及使用過程中所積累的經驗、可靠的技術資料，經過與所設計的齒輪在用途、工作條件及技術性能上作對比后，選定其精度等級。According to the accumulated experiences and reliable technical data from past products design, performance test and use procedure.Choosing the accuracy classes after comparing with the designed gears on applications, working conditions and technical functions.,各種機械采用齒輪的精度等級 The adoptted gears accuracy classes for different machines,2.齒輪精度等級標注 The label for gears accuracy class,-0.330 -0.495,（ ）GB/T10095.22001,例：7-6-6 G M GB/T10095.22001,7 F L GB/T10095.22001,表示齒輪第、公差組的精度分別為7級、6級、6級。The precision accuracy of the tolerance groups , and for gears are respectively as class7,6 and 6.,齒厚上、下偏差代號分別為、。Gears upper and lower deviation codes are respectively as and .,二.齒厚極限偏差代號 The code for limit deviation of tooth thickness,齒厚極限偏差的數值=齒距極限偏差（fpt）的倍數 The numerical value of limit deviation of tooth thickness =The multiple of transverse pitch limit deviation,國標規(guī)定:14種齒厚極限偏差的數值，大寫的英文字母表示。National standard:14 kinds of numerical values for limit deviation of tooth thickness and indicated by capital letters in English.,三.齒輪坯的精度和齒輪面粗糙度 Precision of gear blanks and Roughness of gear surface,齒坯公差 Tooth blank tolerance,齒坯基準面徑向和端面跳動公差 Radial and end face run out tolerances for gear blanks basic face,齒輪表面粗糙度 Roughness of gear surface,齒面的表面粗糙度對齒輪的傳動精度(噪聲和振動)、表面承載能力(點蝕、膠合和磨損)和彎曲強度(齒根過渡曲面狀況)等都會產生很大的影響。 Gears surface roughness would exert big effects on gears transmission accuracy(Noise and vibration), surface carrying capacity(corrosive pitting, glue together and wear and tear)and bending strength(Fillet surface condition).,單位：m,四、圖樣標注例 The examples for pattern annotation,