simulation of a planetary gear system

[Raza]

I am trying to run a simulation of a planetary gear system consist of four planetary gears, one sun gear & a ring gear. The planet gears will be revolving around the sun & the ring gear. I am trying to run this simulation on Promotion but I am having problems. I already defined the gear connections, material & has made the sun gear as a driver & give it a certain angular velocity. Every time when I try to run the moton analysis on it, I got the message showing that engine is not connected. Can anybody help me in this problem?

 

[amd450]

Which version are you using? In the Wildifire Mechaninsm you have that assemble the 4 planetary and the sun with pin, after

you assign the gear movement and every one, saying the relation between its. About this message I

 

[Raza]

I m using ProE2001.

I think mechanism option is not gonna work coz there will be interferences in the gears if I'll use mechanism method. I tried the mechanism method with one sun & one planet gear & I was able to rotate both on their axes but there were interferences.

Promotion has the option of gears & gear pairs so that there will be no interferences between the gears.



Raza

 

[Mloew]

What is it you are trying to simulate? I can imagine that with the simple use of parameters and relations one could simulate the rotational movement of a planetary gear-set in Pro/E 2001 quite easily.



Best regards,



Matthew Ian Loew

Luck is the residue of design.

Branch Rickey

 

[Raza]

Thankx for replies



I m trying to rotate sun gear on its axis & the planetray gears around their axis as well as aorung the ring gear just like a planetary gear system. I dont know how we can do it by relations? I m realtively new in ProE.

I will really appreciate if anybody can help me in doing this simulation.



Raza

 

[xcad]

can you send me the part so i can study it ?



karavasilis

 

[jbuckl]

Are the gears assembled using 'cylinder' surfaces at their pitch diameters?



There was an old ptc log about preventing 'slip' with the old pro mechanism.



Hope u can get a result .

 

[donha]

Out of the manual:

You can change the absolute tolerance by changing the relative tolerance or the characteristic length, or both.



1. Click Mechanism > Settings. The Settings dialog box opens.



2. If you want to change the Relative Tolerance setting for your assembly, deselect the check box and enter a value between 1e

 

[Raza]

I cannot mail this file to u. Its a huge file. (reply to xcad)



I didnt use the cylinder connections infact I used the pin connections. I was able to rotate the sun gear & a planet gear on their own axis but with pin connection I could revolve the planet gear aound the sun gear. The planet has to be rotate on its own axis as well should revolve around the sun gear. What option u think I should use in order to do that? (reply to jbackl)



I m not running an analysis I just want to perform a simple simulation. (reply to donha)

 

[Mloew]

If you still wish to to the simulation in Pro/E, try using the formulas found on this page:



http://www.efunda.com/designstandards/gears/gears_epicyclic_ratio.cfm



Best regards,



Matthew Ian Loew

Luck is the residue of design.

Branch Rickey

 

[Raza]

Thankx for giving the URL. I have never worked on the relations but I will try it not.

I was still wondering if somebody knows how to do this simulation by using mechanism or by using promotion.



Raza

 

[Raza]

sorry I mean to say that I will try it now



Raza

 

[skraba]

I believe MDO has an option called Cam-Follower connections. I'm not sure this would help, but you can get some ideas out of it.

 

[cjmohan]

Hello Razza and others


I duno if this the problem is solved but, I wanted to write back because this is precisely, ( i mean rotating the planetary gear system ) the work we do a lot.


If you are using ProMech Motion, make cynlindircal surface (PCD as the dia.)on each gear and then cut the teeth. use these surfaces as gear surfaces and u can assign them some transparent colors.


Choose the SUN and Planet surafaces as Spur gear surfaces ( or even helical). But for RING gear, choose the Option Ring gear. Only then can u mesh the planet and sun.


A planetary stage needs a planet carrier, that will keep all the planets connected. Make some rough planet carrier and make it a seperate body. This PC has to be connected to the Groung using a Pin/Cylindrical joint.


put each Planet in seperate bodies ( 4 bodies in ur case). join planet bodies to the planet carrier body using four Pin/Cylindirical joints.


Make the ring gear as ground. join the sun to ground by another pin/cyl. joint.


make 8 gear connections ( 4 Pla-sun + 4 ring-sun).


totaly there must be6 gear surfaces ( 1 sun, 4 planets, 1 ring) ,6 pin/cyl. joints (1 gnd-sun, 1 gnd-PC and 4 PC-pla)and 8 gear connetions


now try running.