齿轮设计公式Word文件下载.docx

1、 .al=arc co 1 co sa / （z i + 2h；） = 29.841Ea = 1.712aa2 = arccosE%cosa/（Z2 + 2h*） = 23.623 zx（tanaal 一 tana） + z2 （tana 一 tana）=】门=0.873计算接触疲劳许用应力aHb查得小齿轮和大齿轮的接触疲劳极限分别为iml = 600MPa, QHlim 2550MPao计算应力循环次数：Nj = 60nijLh = 4.1184 X 109Nx QN2 = y-= 1.2672 X 109査得接触疲劳寿命系数KHNi = 0.90, Khn2 = 095。 失效概率为1%,

2、安全系数S= 1, , KHNlaHlim 1 匚ghi = = 540MPa2h2 = Khn2；he2 = 523MPa2h=523MPa取两者中的较小者作为齿轮副的接触疲劳许用应力，即aH = aH2 = 523MPa2）试算小齿轮分度圆直径= 32.4N. mm WON.mm b查得齿间载荷分配系数Km = 1.2 o由表10-4用插值法查得7级精度、小齿轮相对支承非对称布置时, 齿向载荷分布系数Kp = 1.416 o由此得到实际载荷系数Kh = KAKvKHaKp = 1.835按实际载荷系数算得的分度圆直径3.按齿根弯曲疲劳强度设计（1）试算模数试选Kr = 1.3计算弯曲疲劳强

3、度用重合度系数0.75丫 = 0.25 + =0.688计算嗇 查得齿形系数31 = 2.65, YFa2 = 2.24査得应力修正系数Ysai = 1.58, Ysa2 = 1.75查得小齿轮和大齿轮的齿根弯曲疲劳极限分别为aHim x = 500MPa, aHiin2 = 380MPa査得弯曲疲劳春命系数1叭=0.85, Kn2 = 0.88取弯曲疲劳安全系数S= 1.4,“h =人朋丄:日血丄=303.57MPa yF2 =加2 严】2 = 238.86MPaFalsal 小 cc= 0.0164叶2）试算模数（2）调整齿轮模数1）数据准备圆周速度Vdx = nitZi = 24.072

4、nmi60xl000 = 180m/s齿宽bb =帕山=24.072nmi宽高比b/hh = （2h； + c4）mt = 2.257mmb/h = 10.672）计算实际载荷系数Kf查得 Kv = 1.06Fj =于=1.648 X 103Niz fA = 68.46N. mm WON. mm b由此查得Kf“ = 1.2由表10-4用插值法査得Kh卩=1.414,结合b/h = 10.67査得心0 = 1.34则载荷系数为心=KAKvKFaKFp = 1.45m = 1.098mm所以3,Kfm =叫 =1.098mm（心由于齿轮模数m的大小主要取决于弯曲疲劳强度所决定的承载能力，而 齿而

5、接触疲劳强度所决定的承载能力，仅与齿轮直径有关，可取由弯曲 疲劳强度算得的模数1. 098mm并就近圆整为标准值m = 按接触疲劳强度算得的分度圆直径山=39.084mm.所以z】=严=31.27。取Zi = 32,则Z2 = iz2 = 104Zi = 34z2 = 111为使大小齿轮齿数互为质数，经调整得1.几何尺寸计算分度圆直径山=Zm = 42.5 mmd2 = z2m = 138.75 nuu中心距（d1 + d2） -a = = 90.625nun齿轮宽度b = （Jjddi = 42.5 nun小齿轮齿宽加宽（5-10） mm,即b = b + （510）nmi = 47.552

6、.5mni取b = 50mm,大齿轮b? = b = 42.5mm2.调整中心距后的强度校核采用变位法调整中心距为90mm（1）计算变位系数和计算啮合角，齿数和，变位系数和，中心距变动系数和齿顶高降低系数X = 0.08,X2 = 0.55Ay= xE -y = 0.013查得分配变位系数Xi = 0.08, x2 = 一0.55（2）齿面接触疲劳强度校核为节省篇幅，仅给出计算结果：Kh = 1.872, T = 1.983 X 104N.mm,机=1，山=42.5mm, i = 3.25,ZH = 2.57, ZE = 189.8MPai& Z = 0.862,所以ZHZEZe = 472.

7、7MPa 52.239mmdlt 1 T （-rP）2 = 52.239mmJ 札 i 6（2）调整小齿轮分度圆直径圆周速度vIT dltnHv =1.2 m/s60X 1000 7b = t）ddlt = 52.239mm计算实际载荷系数Kh。査得Ka = 1查得反=1.06齿轮的圆周力KAFti .b=45.3N. nun 100/V.mm2T=石=2.368 X 103N査得齿间载荷分配系数Km = 1.2 o由表10-4用插值法查得7级稱度、小齿轮相对支承非对称布置时，得 齿向载荷分布系数勺=1.420 oKh = KAKvKHaKp = 1.8063k7dx = dlt ；/ = 5

8、8292mmJKHt及相应的齿轮模数ni = 2.429mmdim = = 2.42 9nmiZlY8 = 0.25 + =0.693査得齿形系数ai = 2.68, YFa2 = 2.28査得应力修正系数Ysai = 1.58, Ysa2 = 1.73査得小齿轮和大齿轮的齿根弯曲疲劳极限分别为aHim i = 500MPa, = 380MPa查得弯曲疲劳寿命系数Kfni = 0.90, KN2 = 0.90 aFi = Kfni Jimi = 321.43 MPab = Gddi = 35.28mm 宽高比b/h + cjn* = 3.308mm b/h = 10.672）计算实际载荷系数K

9、f 査得 Kv = 1.02Ftl = = 3.507 X 103N牛=99.4N. mm 100Ar. mm. b由此査得Kf” = 1.2由表10-4用插值法查得Khp = 1.416,结合b/h = 10.67查得心0 = 1.31Kf = KAKvKFaKFp = 1.60由丁齿轮模数m的大小主耍取决r弯曲疲劳强度所决定的承载能力，而 齿面接触疲劳强度所决定的承载能力，仅与齿轮直径有关，可取由弯曲 疲劳强度算得的模数1. 575mm并就近例整为标准值m = 2mn】，按接触疲劳强度算得的分度圆胃径山=58.292mm,所以巧=詈=29.146。取Zi = 30,则Z2 = iz2 =

10、75zx = 37 z2 =93Zi = 3722 = 934几何尺寸计算 分度圆直径dx = zxni = 74nmid2 = Z2U1 = 186mma = 130nmib = ddi = 74mmb = b + （5 10）mm = 79 84 mmbi = 80mm,大齿轮b2 = b = 74mm5.齿轮强度校孩（1）齿面接触疲劳强度校核Kh = 1.85, T = 6.186 X 104N.mm, 4）d = 1,山=74nini, i = 2.5,ZH = 2.5, ZE = 189.8MPa1/2, ZGddi2KhT1ZhZeZ = 363.7MPa （2）齿根弯曲疲劳强度校

11、核Kf = 1.70, & = 6.186 X 104N. mm, YFal = 2.44, YFa2 = 2.20, al = 1.66, a2 = 179, Y = 0.673, 4）d = 1, m = 2, zx = 37,所以 2KfTYf証 YsYg 严Qfi = : ； = 5235MPa aF2gm Z 2KFT1YFa2YSa2Y =_ 丄鹭严=50 goMPa 齿数Z = 37, Z2 =93,模数m = 2,压力角a = 20,中心距a = 130mm 齿宽5 = 80mm, b2 = 74mm。小齿轮选用4OCr （调质），大齿轮选用 45 （调质）。齿轮按7级精度设计。