文档介绍：概述
Function: applied for transmitting rotating motion and dynamics between crossing axes, angle of axes is arbitrary value.
作用:用于传递交错轴之间的回转运动和动力,两交错轴间的夹角可为任意值,通常为90度。
Formation: if the number of teeth of single bevel gear is very small,
and when β1 is very large, gear on cylinder body constitutes multi-circle full spiral.
形成:若单个斜齿轮的齿数很少(如z1=1)而且β1很大时,轮齿在圆柱体上构成多圈完整的螺旋。
The derived gear is called: worm. Meshing member is called: worm gear.
所得齿轮称为:蜗杆。而啮合件称为:蜗轮。
Drawbacks
缺点:
Merits
优点:
1)Large drive ratio, compact structure
传动比大,结构紧凑
2)Stable drive, light noise.
工作平稳,无噪声
3)Can revese self-lock in specific condition
一定条件下反行程可自锁
Low efficiency, relative gliding speed is high, friction and abrasion is heavy, gear ring of worm is made from the precious material (such as bronze), high cost.
效率较低,相对滑动速度大,摩擦与磨损严重,蜗轮齿圈一般需用贵重的减摩材料(如青铜等)制造,成本高。
Material and failure forms of worm drive
蜗杆传动的材料和失效形式
一、蜗杆传动的失效形式和设计准则
与齿轮传动类似:点蚀、胶合、磨损、折断
∵相对滑动速度vs↑→η↓、发热↑
Main invalid forms: glue, pitting and abrasion. Usually occurs on the teeth of wormgear.
主要失效形式:是齿面胶合、点蚀和磨损,而且失效通常发生在蜗轮轮齿上。
Design criterion of worm drives
2. 蜗杆传动的设计准则
To avoid failure caused by excessive abrasion of tooth face, we should make:
为了防止齿面过度磨损引起的失效,应进行:
1)Bending fatigue strength calculation of worm’s dedendum
蜗轮的齿根弯曲疲劳强度计算
2)Contact fatigue strength calculation of worm’s tooth face
蜗轮的齿面接触疲劳强度计算
To avoid failure caused by rigidity deficiency of worm, we should make: Rigidity calculation of worm
为了防止蜗杆刚度不足引起的失效,应进行:蜗杆的刚
度计算
To avoid failure caused by overheat, we should make
为了防止过热引起的失效,就要进行:
Calorific balance calculation of drive system
传动系统的热平衡计算
There are abrasion of teeth face and gear rupture in opening worm drives, so should guarantee bending fatigue intensity of worm drives.
开式蜗杆传动多发生齿面磨损和轮齿折断,因此,应以保证轮齿弯曲疲劳强度进行计算。
There is glue or pitting in closing worm drives. So, usually calculate according to contact fatigue intensity of teeth face, check according to bendin