Creo mechanism belt

[gchen-2]

‌i don't know why I cannot set the belt mechanism with the pulley I download from Andymark, when I sepect the first reference on the first pulley, its ok, but then I cannot select anything from the second pulley, any solution of suggestion?

[sm · Accepted solution]

Gary, when picking the belt connections, try picking the driving connection instead of the components. Easiest way to do that is to change the smart filter in the lower right corner to "Connection". Once you have selected your two pin connections, you can come back and set a diameter value for each one. This is not a good example since it is gears, but it does illustrate how to connect the pin joints and make a belt connection.

[gchen-2]

H‌i, Mr. Morris

thanks for the help! I figure it out! I have a little question about the E*A, I don't know what does that stands for, what do I need to do with that parameter?

[gchen-2]

by the way, i really really enjoy the new ptc community, it's waaaaaaaaay better than the old one, that is one of the best gift we got after the championship, thanks!

‌

[sm]

Gary, the Help Center is not very clear on how this value is used, only what it is. Look for a topic named "About the Belt and Pulley User Interface" if you cannot access the link. It describes the E*A value as: "Defines a Young’s modulus multiplied by the belt section area. Type a value into the collector or select a value from the list of most recently used values."

Young modulus is a material property (elasticity coefficient), and A is the cross-section area of the belt. From what I can see, it is only used for a Dynamic Analysis and will not have any effect on the overall operation of your belt connection.

If you really want to get into the engineering and design aspects of belt design, check out this Timing Belt Theory guide.

[gchen-2]

Mr. Morris, thanks for the help, i got a little problem then, since i thought it's something i didn't set up properly with E*A. When i finish define the servo and the belt mechanism, i do the analysis, but the main driving pulley and the passive pulley are not turning at the same speed, exactly the same pulley, but the speed is seemed like to be halved. And when the motion is being transferred into the third pulley(same belt, same pulley), the speed is being halved again, I'm not sure what i did wrong, is that the problem of the Pin connection? I redo it in Pro/Eng wildfire 5 and they all works fine. Thanks for the help again!!!!!!!

[sm]

Double check the values for # of Wraps for each pulley. By default they should all be 1. If they are not all 1, they will not rotate at the same speed. Also make sure you don't have any gear pairs defined that could be interfering with the belt definition.