Gear box in catia
مراحل طراحي گيربكس Internal gear

مراحل طراحي گيربكس Internal gear

Design of the gearbox
 
 
 
 

Zipped part: gearbox.zip (1.4MB).

2 Design of the gearbox

The first step consists in designing an internal gear.
The principle is the same as for a classic spur gear.
The main difference is that the metal is outside of the teeth.


Internal gears are less frequently
used than spur gears, and
more complex to produce.
So their cost is usually twice
the cost of a spur gear.
The second step consists in designing a planet carrier
for the spur gears that will roll in the internal gears.

Here is a simple carrier,
machined in a single part.
At the third step, the first internal gear is duplicated for making
a second internal gear having different parameters:
  • blue internal gear: Z=42 m=0.8mm
  • green internal gear: Z=41 m=0.8mm
The green gear is fastened on a carter.
The blue gear is the output of the gearbox.
The planet carrier in the input of the gearbox.
At the fourth step, we add the planet gears and their shafts:
a second internal gear having different parameters:
  • blue planet gear: Z=17 m=0.8mm
  • green planet gear: Z=16 m=0.8mm
That combination gives a gearbox ratio equal to:
1 - ZA/ZB * ZD/ZC = 1 – 42/17 * 16/41 ≈ 1 : 28
At the fifth step, the 3 shafts are pressed against the 3 couples of spur gears.
The pressure between the 3 shafts and the spur gears must be high enough
for transmitting the torque
between the green spur gears
and the blue spur gears.


Note that the parts are simple enough for
allowing a fully automated manufacturing
without requiring any manual operation.

Now the gearbox is completed.
The output internal gear (in blue)
is pressed against the output shaft.
End of File
 

 

نوشته شده توسط محمدرضايي  

 
 

 

 
not right cilck

not copy