BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI - Universitatea ...

Bul. Inst. Polit. Iaşi, t. LVI (LX), f. 2, 2010 79
c) For the unsymmetrical milling with t > D/2, we suppose that for a
number of teeth that simultaneously cut z = z + z , the values of cutting
force components will be obtained as the sum of the values of cutting force
components corresponding to a tooth z , Eqs. (3), and a tooth z , Eqs. (5).
(5)
F
F
Z
X
=
=
z
−1
s4
∑
z
1
s4
∑
s1
2π
Fz
cos( zi)
+
z
−1
1
2π
Fx
cos( zi)
−
z
Y
y
s
3
z
s
s4
∑
z
1
−1
1
−1
s4
∑
s
1
F = F ⋅ z .
4
s
4
s4
2π
Fx
sin( zi
) ,
z
2π
Fz
sin( zi
) ,
z
The values of cutting force components corresponding to the total number
of teeth that simultaneously cut ( z ) result using the Eqs. (6).
(6)
F
F
Z
X
=
=
z / 4
∑
0
z / 4
∑
0
2π
Fz
sin( zi
) +
z
2π
Fx
sin( zi
) +
z
s
3
z
−1
s4
∑
z
1
+
−1
s4
∑
2π
Fz
cos( zi
) −
z
z
−1
s4
∑
1
x
1
z −1
z / 4
∑
2π
Fx
sin( zi
)
z
2π
F cos( zi
) +
z
s4
2π
− ∑ Fz
sin( zi
)
1 z
F = F ⋅ z .
Y
y
s
3
0
z / 4
∑
0
2π
Fx
cos( zi
)
z
,
2π
Fz
cos( zi
)
z
,
It can be observed that in case of cut-up face milling with cu t' = D/2, and t''
< D/2, the same relations for the cutting force components FZ, FX, FY are
obtained, distinguishing only by the number of teeth that simultaneously cut.
Fig. 3 is illustrating the geometrical models of unsymmetrical cut-down
milling and the same three possible variants: