æ 3 ö . 25 Z . 25 ´ 156 ö æ 3 2 e ÷ m d ³ KT = 1 . 1 ´ 684670 . 3 ´ . 3 < 2500 . 47 ÷ = 2498 1 2 ÷ 2
2
è s h Z 2 ø è 220 ´ 40 ø 原选参数满足齿面接触疲劳强度要求。 2)
确定传动的主要尺寸:
m = 6 . 3 mm , d 1 = 63 mm , z 1 = 2 , z 2 = 39 ① 中心距a
a =
( d 1 + mz 2 ) ( 63 + 2 = 6 . 3 ´ 39 ) 2
= 154 . 35 mm
② 蜗杆尺寸: 分度圆直径 d 1 d1 = 63 mm
齿顶圆直径 d a 1 d a1 = d 1 + 2 h a 1 = (
63 + 2 ´ 6 . 3 ) = 75 . 6 mm 齿根圆直径 d f 1 d f 1 = d 1 - 2
h f = 63 - 2 ´ 6 . 3 ( 1 + 0 . 2 ) = 47 . 88 mm 导程角 tang = 11 . 30993247 ° 右旋
轴向齿距
P X 1 =p
m = 3 . 14 ´ 6 . 3 = 19 . 78 mm 齿轮部分长度 b 1 b1 ³ m ( 11 + 0 . 06 ´ z 2 ) = 6
. 3 ´ ( 11 + 0 . 06 ´ 39 ) = 84 . 04 mm 取 b1 = 90 mm ③ 涡轮尺寸: 分度圆直径 d 2
d 2 = mz 2 = 6
. 3 ´ 39 = 245 . 7 mm 齿顶高 h a 2 = h a * ´ m = 6
. 3 ´ 1 = 6 . 3 mm 齿根高 h f 2 = ( h a * + c * ) ´ m = ( 1 + 0 . 2 ) ´ 6 . 3 = 7 . 56 mm 齿顶圆直径 d a 2 d a 2 = d 2 + 2 h a 2 = 245
. 7 + 2 ´ 6 . 3 ´ 1 . 2 = 230 . 58 mm 齿根圆直径 d f 2 d f 2 = d 2 - 2 m ( h a * + c
* ) = 384 - 19 . 2 = 364 . 8 mm 导程角 tang = 11 . 30993247 ° 右旋
轴向齿距 P X 2 = P X 1 = p m = 3 . 14 ´ 6 . 3 = 19 . 78 mm 涡轮齿宽 b 2
b 2 = 0 . 75 d a1 = 0
. 75 ´ 75 . 6 = 56 . 7 mm 齿宽角 sin( a/ 2 ) = b2 / d 1 = 56
. 7 / 63 = 0 . 9 (2-18)