BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI - Universitatea ...

78 Ana-Maria Matei and Marius-Nicolae Milea
b) Unsymmetrical face milling with t" < D/2, Ψ < 90° and
z 2t
zs = arccos( 1−
) ;
2 2π
D
c) Unsymmetrical face milling with t > D/2 , where t = t' + t"' and t"' = t -D/2,
z 2t
Ψ > 90° and z s = z , where
3 s + z 1 s z = arcsin( −1)
4
s
.
4 2π
D
Fig. 2 – Forces model in unsymmetrical cut-up face milling.
According to the geometrical model of face milling process shown in Fig. 2,
the cutting force components FZ, FX and FY result using the Eqs.(3).
a) zs = z / 4
(3)
1
F
F
Z
X
=
=
z / 4
∑
0
z / 4
∑
z 2t
b) zs = arccos( 1−
)
2 2π
D
(4)
F
F
Z
X
=
=
z
0
s2
∑
z
0
s2
∑
0
2π
Fz
sin( zi)
−
z
2π
Fx
sin( zi)
+
z
Y
y
z / 4
∑
0
z / 4
∑
0
F = F ⋅ z .
2π
Fz
sin( zi)
−
z
2π
Fx
sin( zi)
+
z
z
s
1
s2
∑
z
0
s2
∑
0
F = F ⋅ z .
Y
y
s
2
2π
Fx
cos( zi)
,
z
2π
Fz
cos( zi)
,
z
2π
Fx
cos( zi)
,
z
2π
Fz
cos( zi)
,
z