活顶尖说明书

1、机械设计课程大作业机床活顶尖设计说明书学 院： 求是学部 专 业：机械设计制造及其自动化 班 级： 1 班 姓 名： 詹颖纯 学 号： 3010201267 指导老师： 项忠霞 2013.04机床活顶尖设计任务书机械设计大型作业编号06姓名：詹颖纯 专业 机制 年级 2010级 班级 求是1班 设计完成日期 2013 年 04 月 29 日指导教师 项忠霞 一、题目：机床活顶尖原始数据和已知条件:莫氏圆锥号D1D2L1L2L3L447031.26735102.7238108顶尖处受力：径向力Fr =1500N 轴向力Fx =750N转速：n=500r/min设计寿命：3000h二、工作量1、计

2、算说明书一份；（将任务书置于计算说明书首页）2、装配图一张。三、设计要求1、确定轴承组合结构方案；2、对轴承进行寿命计算和静强度计算。目录1 轴承型号初选·····································&

3、#183;······32 轴承的受力计算·········································

4、83;32.1 轴承径向力计算···································32.2 轴承内部轴向力计算··········&

5、#183;····················32.3 轴承轴向力计算···························&

6、#183;·······32.4 轴承当量动载荷计算·······························33 轴承寿命计算·······&#

7、183;·····································44 轴承静强度计算校核··········&#

8、183;··························45 顶尖心轴设计······················

9、;······················45.1 心轴材料选择··························

10、··········45.2 心轴尺寸计算····································4 5.2.1 各轴段直径

11、计算·······················5 5.2.2 各轴段长度计算·······················56 端盖设计

12、················································56.1 端盖材料选择&

13、#183;···································56.2 端盖结构设计············&#

14、183;·······················57 套杯设计·························&

15、#183;······················57.1 套杯材料选择·························&#

16、183;··········57.2 套杯结构设计····································68 支撑体设计&

17、#183;·············································67.1 套杯材料选择··&#

18、183;·································67.2 套杯结构设计··············

19、83;·····················69 密封件选择···························&

20、#183;··················610 设计参考文献·····························

21、83;··············6计算及说明 结果1. 轴承型号初选根据任务书所给要求及原始数据，考虑到活顶尖所受轴向力较大，但计算转速不高，且安装在车窗上，有冲击载荷，故选用圆锥滚子轴承，初步选定型号为30204，并采用“面对面”安装方式。查机械设计手册得30204号圆锥滚子轴承相关参数为：e=0.35,Y=1.7，Y°=1，C=28.2KN，C°=30.5KN 2. 轴承的受力计算2.1. 轴承径向力计算活顶尖轴系受径向力情况如图

22、1图1列平衡方程：FR×60+40-FR1×40=0将 FR=1500 N 入上式后可得：FR1=3750 N又FR1=FR2+FR，FR2=FR1-FR=3750-1500=2250 N2.2. 轴承内部轴向力计算根据公式3000系列的圆锥滚子轴承的内部轴向力FS=FR2Y，得FS1=37502×1.7=1102.9 N， FS2=22502×1.7=661.8 N2.3. 轴承轴向力计算可得轴向力为：FA1= FS1 =1103NFS2-Fx=750-662=88N FA2=Fs2 =662N FS1+Fx=662+750=1852N 取两者中的较大

23、值，即FA1=1103 N， FA2=1852 N2.4. 轴承当量动载荷计算对轴承1有：FA1FR1=11033750=0.294e ,故查表得：X=1，Y=0对轴承2有：FA2FR2=18522250=0.823>e ,故查表得：X=0.4，Y=0.4cot=0.4×1.50.35=1.7轴承型号30204FR1=3750 NFR2=2250 NFS1=1102.9 N FS2=661.8 NFA1=1103 N FA2=1852 NX=1，Y=0X=0.4Y=1.7计算及说明 结果P1=fPX1FR1+Y1FA1=1.5×1×3750+0×1

24、103=5625NP2=fPX2FR2+Y2FA2=1.5×0.4×2250+1.7×1852=6073N两轴承的当量动载荷取大值进行寿命验算：P= P2=6073N3. 轴承寿命计算寿命指数 =10/3寿命 L10h=10660nCP=10660×50028.2×1036073103h=5634h>3000h符合设计要求。4. 轴承静强度计算校核查表得：径向载荷系数X0=0.5，轴向载荷系数Y0=0.22cot=0.22×1.5 /0.35=0.94取静强度安全因数S°=3则轴承的当量静载荷P01=X0×FR1+Y0×FA1=0.5×3750+0.94×1103=2912 NP02=X0×FR2+Y0×FA2=0.5×2250+0.94×1852=2864 N取两者较大值，故 P0=P01=2912 NC0P0=30.5×1032912=10.5S0满足设计要求5. 顶尖心轴设计5.1. 心轴材料选择45号钢5.2