
For all the possible gear ratio in fractions of seconds calculate
 Milling of gears with the gear hob, gear hobbing, (PFAUTER).
(Gears of diferential for additional rotation of the workpiece during manufacturing of helical gears)
 For gear profile grinding machines, (NILES)
 For gear tooth forming machine, (MAAG, LORENZ)
(change gears for rolling processes)
 Thread grinding machine:
(change gears for the pitch, screw).
Change gears are mostly from two pairs of gears assembled, or double gear ratio:

actual valuegear ratio: i= 
A 
x 
C 
B 
D 
Data input:
desired value: (given), or
Arithmetic expression, Based on the machine data
Only decimal point "." is allowed, never comma ","
Largest/smallest number of teeth in the existing gear wheel set
desired preciseness (on, e.g. rounded to seven decimal figures):
rounded desired value = rounded actual valuegear ratio
Arithmetic expression:
e.g., For gear profile grinding machines, (NILES),the gear ratio for change gears of differential is expected
in accordance with the following expression:
i=119.5372*cos(ß)/m/z
e.g., For a gear
 Modul: m=2,5
 number of teeth: z=38
 Helix angle: ß=15°
In the input field for desired gear ratio is value,
or an arithmetic expression, referring to SQLlanguage entered.
desired gear ratio:
1.21541124928717, or
119.5372*cos(pi()/180*15)/2.5/38
pi()/180=angle in rad
or, for Helix angle of ß=15°22`18":
119.5372*cos(pi()/180*(15+(22+18/60)/60))/2.5/38


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