Re: So it may be the driveshaft???

Posted by cgrey8 from alcnetwork.automatedlogic.com (68.208.14.49) on Tuesday, December 07, 2004 at 10:17PM :

In Reply to: So it may be the driveshaft??? posted by cgrey8 from alcnetwork.automatedlogic.com (68.208.14.49) on Tuesday, December 07, 2004 at 10:16PM :

Registered Ranger

As for the phasing of U-joints, I know exactly what you are referring to. U-joints, unlike CV-joints, do NOT have a contant rotational velocity when they are working at an angle. The wider the angle, the more variance in speed the output will be.

I saw a demo of this where they had a set of chain sprokets welded to a driveshaft before the 1st U-joint, in the middle, and then past the 2nd U-joint. To display the concept, they took a playing card and ran it into the teeth of the sproket while a motor spun the driveshaft which made a noise similar to the noise a playing card would make in the spokes of a bicycle wheel.

When all was straight, it was no surprise that all 3 sprockets were like a straight pipe with no variance. The pitch frequency was constant with no fluctuation. However as the angle increased, you could HEAR the center of the driveshaft increasing and decreasing in speed (sound frequency) due to the U-joint. At the other end, the other U-joint cancelled this variance out because they were welded to the shaft in phase (parallel). When they are out of phase, the effect wouldn't be cancelling, but rather augmented and even worse. So they know what they are talking about when it comes to the Ujoint phasing...

CV joints solve that problem, that's why they are called "Constant Velocity"

I hope you do figure it out. Some problems are solved by throwing money at it to the point that you solve it without really knowing/understanding what fixed it.

Good luck on that...

Chris

Automated Logic Follow Ups: Post a Followup Name: E-Mail: ( default ) Subject: Message: : As for the phasing of U-joints, I know exactly what you are referring to. U-joints, unlike CV-joints, do NOT have a contant rotational velocity when they are working at an angle. The wider the angle, the more variance in speed the output will be. : I saw a demo of this where they had a set of chain sprokets welded to a driveshaft before the 1st U-joint, in the middle, and then past the 2nd U-joint. To display the concept, they took a playing card and ran it into the teeth of the sproket while a motor spun the driveshaft which made a noise similar to the noise a playing card would make in the spokes of a bicycle wheel. : When all was straight, it was no surprise that all 3 sprockets were like a straight pipe with no variance. The pitch frequency was constant with no fluctuation. However as the angle increased, you could HEAR the center of the driveshaft increasing and decreasing in speed (sound frequency) due to the U-joint. At the other end, the other U-joint cancelled this variance out because they were welded to the shaft in phase (parallel). When they are out of phase, the effect wouldn't be cancelling, but rather augmented and even worse. So they know what they are talking about when it comes to the Ujoint phasing... : CV joints solve that problem, that's why they are called "Constant Velocity" : I hope you do figure it out. Some problems are solved by throwing money at it to the point that you solve it without really knowing/understanding what fixed it. : Good luck on that... : : Chris Optional Link ( default ) URL: Title: Optional Image Link ( default ) URL: