Stober PK - Page 450

15.1 Symbols in formulas
The formula symbols for values actually present in the application are marked with *.
Symbol Unit Explanation
a
th
– Parameter for calculating K
mot,th
a
thEL
– Parameters for calculating K
mot,th
(dependent on the mounting position)
B
10
– Number of cycles after which 10% of components have failed
B
10D
– Number of cycles until 10% of components have failed dangerously
C
2
Nm/
arcmin
Torsional stiffness relative to the gear unit output
C
2k
Nm/arcmin Tilting stiffness
C
dyn
N Dynamic bearing load rating
ΔJ
B
kgcm
2
Additive mass moment of inertia of a motor with brake
Δm
B
kg Additive weight of a motor with brake
Δn
1
rpm Speed difference at the input
Δn
2
rpm Speed difference at the output
Δφ
2
arcmin Backlash at the output shaft with a blocked input
Δφ
2red
arcmin Reduced backlash at the output shaft with a blocked input
Δφ
2redI
arcmin Reduced backlash (backlash class I) at the output shaft with a blocked input
Δφ
2redII
arcmin Reduced backlash (backlash class II) at the output shaft with a blocked input
Δφ
B
arcmin Brake backlash
Δφ
tot
arcmin Total backlash
Δt s Timespan
Δϑ K Temperature difference
η
get
% Efficiency of the gear unit at nominal torque
η
gt
% Efficiency of the screw drive
ED
10
% Duty cycle based on 10 minutes
F
2ax*
N Actual axial force at the gear unit output
F
2ax100
N Permitted axial force at the gear unit output for n
2m*
≤ 100rpm (without ra-
dial force)
F
2ax20
N Permitted axial force at the gear unit output for n
2m*
≤ 20rpm (without radial
force)
F
2ax,eq*
N Actual equivalent axial force on the gear unit output
F
2axN
N Permitted nominal axial force at the gear unit output (without radial force)
f
2PU
Hz Output frequency of the power unit
f
PWM,PU
Hz Frequency of the pulse width modulation of the power unit
F
2rad*
N Actual radial force on the gear unit output
F
2rad100
N Permitted radial force at the gear unit output for n
2m*
≤ 100 rpm
F
2rad20
N Permitted radial force on the gear unit output for n
2m*
≤ 20 rpm
F
2rad,acc
N Permitted radial acceleration force at the gear unit output
F
2rad,acc*
N Radial acceleration force present at the gear unit output
F
2rad,acc,1*
N Radial acceleration force present at the gear unit output in the first time pe-
riod
F
2rad,acc,n*
N Radial acceleration force present at the gear unit output in the nth time pe-
riod
F
2rad,eq*
N Actual equivalent force at the gear unit output
F
2radN
N Permitted nominal radial force at the gear unit output
F
ax
N Permitted axial force on the output
F
ax*
N Actual axial force on the output
F
ax0
N Permitted axial force when the motor is at a standstill for holding the load us-
ing the motor torque
F
ax,1*
– F
ax,n*
N Actual axial force in the respective time segment
F
ax100
N Permitted axial force on the output for n
m*
≤ 100rpm
F
ax300
N Permitted axial force on the output for n
m*
≤ 300 rpm
F
ax,eff*
N Actual effective axial force on the output
F
ax,ss
N Axial force that can be transmitted by the shrink ring
fB
op
– Operating mode operating factor
fB
t
– Runtime operating factor
15.1 Symbols in formulas 15 Appendix
450