Lust CDA3000 - A.2.5 Friction

A-14
Engineering Guide CDA3000
Appendix A Formula bank
c Rim friction
d Wheel diameter m
d
m
Mean thread diameter m
d
w
Axle/shaft diameter m
F Longitudinal force in screw/
threaded spindle N
F
N
Normal force N
F
R
Friction force with Coulomb friction N
F
W
Tractive resistance to rolling friction N
f Lever arm of rolling friction m
g Acceleration due to gravity m/s²
m Mass kg
M
R
Friction torque Nm
α Angle of inclination of inclined plane deg.
µ
l
Coefficient of friction in longitudinal movement
µ
r
Coefficient of friction in rotational movement
ρ Friction angle in threaded spindles deg.
Friction force of Coulomb friction (dry friction)
Tractive resistance to rolling friction
Friction torque in thread
Table 7.13 Friction
A.2.5 Friction
F
R
F
N
µ
l
⋅ mgµ
l
αcos⋅⋅ ⋅==
F
W
mg
2
d
--
d
W
2
------


µ
r
f ) c++⋅⋅⋅⋅=
M
R
F
d
m
2
------
ρtan⋅⋅=