Начертательная геометрия

9.

161

, D " , D' " , " , 180° . " , 180°, D , ( " D ( . 9.30).

= . 9.30

/ ) , , " ) " , «'-» « ». @ : «' (20», «' R 12», « R12».

" " -, " " l ( . 9.31).

= D D, D' D " , -" , – " . @« » ( . 9.31). C " D. = D - .

4. , D' , « ».. I , , , "D ( . 9.32). / D, " D ,, . 9.33.

l

= . 9.31

= . 9.32

= . 9.33

162

.

~ . ! + D - D,, " " ". @ , & ' -tg ( . 9.34). , 5.

C " , , 1:5," " , 10 50 . % " ( . 9.35).

+ , % , ,. q --, % ( . 9.36). ~ 5 , :1:3.

= . 9.34

= . 9.35

= . 9.36

4 . + 5: K=(D1 —D2)/H

+ " " .

+ , % ,. & 5 5 -( . 9.37). q -.

= . 9.37

3 . ) ( . 9.38) ." , – "D' . 2 % 5, % 1 45°, -–

( . 9.39).

9.

163

/ ) ( " ) 1 , ) D , ( . 9.40).) D " ,( . 9.41).

= . 9.38

= . 9.39

= . 9.40 = . 9.41

@ " "- .

= " :

1.9 % – , D' ) (D' " ( , , . .).

2.4 % – ( . B D ,, , , , , " ( .

" . = , '( , " , " , " " ) " ( ( . 9.42, 9.43).

= . 9.42

164

.

/ " ( . 9.43, ), " D , " " . &+ .

= . 9.43

" , :

" ;

, , - " ;

( - " ( – , + – ).

# ' , -" . @ -" " ( .

D -, .

C ", .

"

@ ") : " ) , -, " " , . -

9.

165

, " ( , ' . " " -" , " .

{ D , , D- ' - " " . = D : - , " , , -.

4 D , D , D' D . # ( D " ( " -. # D "-. @ D" .

2 1 D , D , -D "-. * D -, D .

| D , D ," .

' D , , D .

& " -– , + , " - .

C , . # - D , – " . & D - " D D .

= -( + ).

D " , .

D , - , , , " ( -). N " , " , , (). .

@ D : ,

% ( ) ( . 9.44).

166

.

= . 9.44

• D - , D' ( . 9.44, ), D' D -. ( D' . /" D -, ,( .

' % ( ) D( . 9.44, ). # -. B D , " -D ( – . $ D " ( " "" .

4 D " -' ( . 9.44, ). ( -D " ,' ( - . & + , ) .

D ,( " -. / , , -D " , " -.

9.

167

) ( * " (

' D , - D D + " -.

@ D «*», D : «* = ».

& -, -" .

= , D , " ( . 9.44, , ).

8 D , D' + ( ) . % - ' " . @" , , .

	G-! "
	C	+				-
	" -
	D -
	' ,
					-
	, " -
	.	$,		,
				(
	,			,
	" D , ,						= . 9.45
	( . 9.45). =-
	)
	D		D D .
	-
	) (
	. B							, (-
	( . 9.46, ) -
	' ( . 9.46, , ). & ( D -
	- ( . 9.46, , , , ) . C
		( ( . 9.46, ).

168

.

= . 9.46

/ ( , -( , " . .), " , D' , , D( . !" 45° ( . 9.46, ) ,(10 .

, D' - , ( (- , . 9.47 15 (8), D' . @ ( ( 11, . 9.47) ( -( -( 14 ' 11 = 154, . 9.47).

, " – +' ( ) ( . 9.48), -' D -0: – . 9.49, , " – . 9.49, .

9.

169

( - , .

 

= . 9.47

= . 9.48

= . 9.49

# ( , ( , ), D ( , ( ( ( . 9.50, ) ( (+ ( . 9.50, ).

/ ( D , D (-( (10, . 9.51; + (8, . 9.52).

/ (, ( (-D . @ , . 9.52 (8 " : 64 .

= . 9.50	= . 9.51

= ( " , ' , , "" " -( . 9.53).

170

.

= . 9.52

= . 9.53

/ " , " . .- D' , -, DD «= " 4 », « -" 10 », «@ 8 ».

, . 8.65, . 9.54.

= . 9.54