Motorized Geneva Drive

[Dave_C]

All,

I finished the second of the Geneva Drives that I set out to make. The second one has a 6" driven wheel with a 4 1/4" driving wheel and six index slots instead of 12 like the first one.

This one has a motor undere the case and turns about 30 RPM or so. It has bearing blocks under the mounting plate to keep the shafts in alignment.

It turned out pretty good. I have a video of it running on YouTube! This is my first try at YouTube so I hope it works!

http://www.youtube.com/watch?v=lPA9_cqAC-w

Dave

[Jose Rivera]

BEAUTIFUL WORK ! ! !

Piece of art!!

[GlennW]

That is very nice!

After your video played another popped up for an internal Geneva Mechanism. It looks pretty interresting too!

http://www.youtube.com/watch?v=FlBqMLDdcJc&NR=1

Thanks for posting the finished project.

[seal killer]

Dave--

Well, I think it is beautiful. But, I have no clue where such a drive mechanism may be used.

--Bill

[JHenriksen]

I had no idea thats what that was called. Turret on big Warner Swasey VTL uses that for indexing the tools.

[Jose Rivera]

Type of scape mechanism, same principle but more complex than the ones used on clocks.

[Black_Moons]

If built correctly that looks like it would be a sweet fixture for automated indexing, since it automaticly locks beween steps

[jutz]

A company called Mattson makes some semiconductor manufacturing equipment which makes use of Geneva drives in the material handling system.

A four lobe is used for rotating the handling robot between each of the four stations (two process chambers, one cool-down chamber and the airlock for getting material in and out of the machine).

A four lobe with one lobe cut off for extending and retracting the robot arm (the robot can extend both forward and backward so it uses one of the lobes for extension forward, one lobe for center and the third lobe for extension backward).

A four lobe with two lobes cut off for rotating the airlock transfer platform (the Geneva drive rotates 90° but drives the platform through a 2:1 step up gear to make the stage rotate 180°).

The material handling on the Mattson was fairly reliable although we had to make sure to keep the Geneva drives clean and properly lubed or the large sliding areas would gall and cause all sorts of trouble.

[Peter.]

I can think of a great application for that!

If you made a 12-segment geneva wheel and stuck it on an angle-plate fixture with through-shaft and a 3-jaw the other side you have a great way of quickly indexing round stock to mill it into square, triangle or hexagonal sections.

[DaveD]

Dave--

Well, I think it is beautiful. But, I have no clue where such a drive mechanism may be used.

--Bill

IBM used them on their high speed card punch machine--the 2540--in the 1960s through at least the 1980s when punched cards became mostly obsolete. You remember the rectangular cards with the slots punched in them used to store data? They were 12 rows by 80 columns. The 2540 fed the cards row by row, at about 600 cards a minute, so the little geneva drive was pounding. Some of these machines ran 24 hours a day and lasted for years. The geneva mechanism seldom gave trouble.

I always marveled at this ingenious mechanism, and took one apart once to see how it was made.

[Dave_C]

I'll hi-jack my own thread but since this is related I'll go ahead and post it in this message.

Here is a link to the Steam engine that was completed in January.

Several of you ask for a video and I got it done last night.

http://www.youtube.com/watch?v=szzjGUTHwT0

Enjoy.

Dave C.

[Jose Rivera]

You make nice stuff!!!!