For the Geeks

https://patents.google.com/patent/US4619178

Is this what Yamaha uses now?

Access: Anonymous

Comments

It's not a direct answer to your question but I hope this helps...

The real challenge isn't stopping at a certain spot, it's stopping at a certain spot where the natural fans and the accidental fans stop in the same place. On top of that you have to create something that can be taken apart for transport and finally wont strip out or hurt a person or the system if a finger or something gets in the way of the fans. Toward the bottom it talk about a "transmission" that handles that.

I couldn't find all the artwork, that would show that part. It's a pretty old patent (1985) and there's been a lot of improvements in motor and controller technology, however my guess is they are still using the patent in one way or another on their high end models.

To even geek out more (if that's possible). Has anyone ever seen a named player, who uses tremolo, line up the fans during a concert?

For a long time it always bugged me that the fans on musser vibes are not in sync (the O-Ring drive system can't hold them in perfect synch for extended periods of time). Now I don't care so much... BTW, The Omega addresses this issue very well with it's tremolo system.

I don't know what system Yamaha is using. But there are several options you can consider using more modern technology:

1. Always stop in "Open"
1.1 Stopping in a definable position (eg 20% ​​open)

2. Synchronized run of the two rows
2.1 defined angle offset (possibly adjustable) between both rows

3. Reset with manual (feet) controlled opening of both rows (Love Vibe effect)

4. Find the "zero position" after the frame assembly

Modern stepping motors can be used for all points. Only a specialized controller is needed. The simple control (points 1 and point 2) can actually be built up by every Electronics student. Point 3 is already somewhat more complex, but feasible. You do not really need point 4 if you set each row manually to zero (OPEN) after the frame setup.

I have built a simple version of such a drive unit (12 V, not 110 or 220V) where each row of resonators is driven by a separate stepping motor.
Actually I never use the unit anyway, because I do not like the "wah-wah"-effect.

If you only want to synchronize your Musser-fans and you don't use high speed (could be a little bit noisy), you could switch from your O-ring drive to a toothed belt drive. That costs almost nothing.

Maybe we're getting too far in the weeds, but what the heck this is a geek thing...

Well put windrops. I agree starting and stopping a motor at a given angle is a straight-forward business with a stepper motor. My guess is that Nico Vanderplas uses stepper motor/motors to drive his vibes. My post was related to what Tony was asking if Yamaha is using a the patent in the link he included, perhaps I went out on a tangent.

I don't quite agree regarding a toothed belt would cost next to nothing. Unless I'm overlooking something, one would have to do more than just get a toothed belt. You'd need to do three things: 1) Get the correct pulleys for a toothed belt (easy) 2) align the pulleys somehow or allow for them to be at angles to each other 3) Figure out some kind of tensioning system since toothed belts don't stretch as easy as O-Rings. The resonator fan pulleys on Musser vibes do not run at right angles to each other. It can be worked around as yamaha has done it with toothed belts; however, I think it would require more than a couple hours worth of work.

I sure could be way off here, as I am neither a ME or an EE. If there's a cheap easy way to convert my Musser vibes to a quiet system where I could control the angle of the resonators and I could tear down as fast as my current one and I could plug it into 110V at a gig. I'd pay for it for sure. But maybe I'm in a minority as I like the tremolo. I always wondered if brushless motors would work for this purpose as I understand they are quiet, but maybe they're more high RPM.

At any rate, $200 would be the target since it's the price of Oriental Motor that Musser slightly modifies and uses on the newer vibes.

Now it is difficult because of my bad English skills. Besides, I have no Musser or Yamaha, but only self-built Vibraphones. So I’ll try it with the help of Google translator :) :
The angle between drive and resonator axis should be approximately 5 °.
Then the notch profile of the belt pulleys, has only to be cut out further (without changing the pitch) in order to allow the slanting of the teeth (belts) on the pulley. In addition, higher side diks with rounded edges should be used.
It is no problem to design such a belt pulley and to procure it as 3D printing in plastic for little money. Since no large torques are to be transmitted, the toothed belt requires almost no pretension. With a little luck you should find a suitable belt length, so that no tensioning pulley is necessary.

I have attached a quick & dirty design to show, what I mean.

Supporting Files: 

Never Knew you could look up patents... This is actually really useful information.