, 90, , - .
110 - 140 , , - . . .
: , ( , , ) .
70 - 80. 0.2 1 . , - ( 1 1.5 ) , .
. . , , 2/3 .
. (. . 18.1) R min 0.5 ℓ (0.5 ), ℓ , R 0.5 + m, m , 0.4 0.6 . , R = (0.7 0.8) R max, R = (0.8 0.9) R max.
, , , . . , (. . 18.1).
. . . . (). (. 18.2) ℓ1 R.. ℓ2 . , 45; ℓ2 = 0.7 R.. = 1.7R.. .
|
|
18.2
. ( = 1.7R.), ( < ) ( > ). . , ℓ1, = (0.71)R. .
-, 1.5 . -, - (. 18.3, ). - ℓ - , (. 18.3, ). - ; - , 180 (. 18.3, ). - , - . (. 18.3, ) (. 18.3, )
18.3 : ; 1............... 5 ; ℓ
- .
. , (. 18.4).
18.4
:
-
= max h , (18.1) h , , ; , ( = 0.50.7 );
|
|
-
= (R R. C) tg α, (18.2) R , ; , ( = 2.5 - 3 ); α , .
α = 60--70, , . . ()
ℓ1 = R ctgα C (18.3)
ℓ1 R + m.
, . (. = 4060 ); , . .
. -. - (. 18.5, ), (. 18.5, ) , .
18.5 :
; ; ℓ
(. 18.6). . = 2R., . = 2(R + m). .
18.6 :
1 2 . .