Best belt drive ever! (If I do say so myself)

[Mike Everman]

Hi guys,
I'm not ready for a full release of this, so I'm starting a thread here for discussion. This summer, I'll put a complete product release thread up in the proper place.
This is called ServoBelt. The vid is (almost) self explanitory.

http://www.bell-everman.com/ServoBelt.wmv

It's been tough keeping my mouth shut about it when asked what's the best way to drive a large format DIY NC machine!

Now I can talk about it, as it is patent pending as of Tuesday.

I plan to have parts available online in the fall for people here, though our usual business is OEM customers. It would be a new realm indeed for us to sell parts and not whole systems, but since joining this forum, I have a desire to help!

Enjoy.

[zenbot]

Your link still doesn't work.

[Mike Everman]

Originally Posted by zenbot Your link still doesn't work.

Yeah. Weird.
OK, I changed the name. If you paste what's in quotes in your browser, it should go.

Am I daft, here? I'm using the link icon and typing it in, and it shows right, but does not work. hmmm

[ger21]

I fixed it the first time, but you're renamed version doesn't work. You don't need to use the link icon, just type in the address. Also, you had a backslash instead of a forward slash, but that didn't fix it.

[ger21]

Try this:
http://www.bell-everman.com/ServoBelt.wmv

[Mike Everman]

Thanks, and sorry. I wondered why my experiments to make it work were changing!


www.bell-everman.com/ServoBelt.wmv

Seems to be case sensitive(?)

[ahren]

Mike,

Looks like a really interesting system. Does it use other Bosch parts like the linear rail and blocks, belts, or rack? Any target pricing for, say, an 8.5 foot section of servobelt?

Ahren
www.cncrouterparts.com

[Mike Everman]

Originally Posted by ahren Mike, Looks like a really interesting system. Does it use other Bosch parts like the linear rail and blocks, belts, or rack? Any target pricing for, say, an 8.5 foot section of servobelt?

It will mount to two t-slots on either Bosch or 80-20 45mm series extrusions. We have a version that wraps around so mounting is to two adjacent slots at 90 deg. Bearing rails are currently 20mm Rexroth-Star, standard is the E-line from them, which is an aluminum rail with steel inserts, and aluminum bearing blocks with inserts as well.

The belt carrier is our own extrusion, and has features to hold limit sensors (the Bimba pneumatic cylinder sensors).

We're not quite in production yet and still building our test portfolio. Pricing is forthcoming.

[Mike Everman]

YouTube - ServoBelt: amazing belt drive

YouTube - ServoBelt: amazing belt drive

[Bobbyr70]

I like it, I had considered a belt assembly using just a tight tough belt stretched from end to end but most of the belting I looked at didn't like being bent backwards. Being I am not an engineer by trade, What kind of belt sizing would I have to use for a roughly 250 lb gantry attempting to achieve 875 imp. I don't know how fast I can accelerate it being I only have servo motors capable of 900 oz. I am using dual x axis drives. Hoping it will work well. I did a little home work and this is what I came up with for motors. I would like to purchase 2 of these units with 8.5' travel. Is that something that could be at a reasonable request and of couse HOW much will I have to shell out?

[Greolt]

Interesting concept Mike. Looks good.

At first I thought you had only one roller each side to keep the belt engaged with the rack but then I see you have two rollers each side.

Is the rack something you have manufactured to match the belt pitch or is it another length of belt with teeth up?

Greg

[Mike Everman]

Originally Posted by Bobbyr70 ....What kind of belt sizing would I have to use for a roughly 250 lb gantry attempting to achieve 875 imp. I don't know how fast I can accelerate it being I only have servo motors capable of 900 oz. I am using dual x axis drives. ...

I do engineer these things, but still like to think in simple terms. Just pulling it out of the air, check how wide you can get 5mm pitch belting. (from SDP(?))
So you have 900 in-oz, that's 56.25 in-lb. Let's say you use a 1" pinion, the radius is .5". So 56.25/.5 is the linear force you can deliver, 112.5 lb. Each motor will see 125 lb of force per g. You are capable of almost a g with a one inch pinion! 1g is 32.2 ft/sec/sec, so I'll leave the last math to you, but acceleration will not be your problem. What you will deal with is stiffness of the drive line, and that's where ServoBelt will excel. There's no stretchy belt in the stiffness equation.

Originally Posted by Bobbyr70 ....I would like to purchase 2 of these units with 8.5' travel. Is that something that could be at a reasonable request and of couse HOW much will I have to shell out?

I don't know yet. We're making them for a few early adopter OEM's. The belt carrier is going to be an extrusion, but is now a rather expensive long machined part. I'll be selling this extrusion, belting and all other parts. I expect for folks around here it will be in kit form, but who knows. You can do this entirely yourself, though. Just know that you need flanges on the pinion if you want to run the belt on something flat. (we capture both sides of the belt stack so no flanges are needed anywhere in the drive unit.)