Linear/Vibratory Feeders

Can anyone shed some light on linear feeders?
I am looking at feeding Syringe parts in to an assembly machine.

1. Any preferred brands?

2. What kind of feed rate can I expect?
1" diameter barrels. 180 per minute, sustained.

3. Any resources for Escapement/Stripping strategies?
Any good books, etc.?

4. Track design. 304 SS tracks, at least where the product is handled.
What about the finish of the track rails? Should I polish most of the track, and maybe have the contact strip for the parts lightly blasted for "traction"?

5. Any advice on parts that may want to hang? The barrels will hang down, no question. The caps are shorter, and may not want to hang down so reliably.

6. The system needs to switch out between various products, so the rails need to be adjustable. Apparently, the weight of the product is not as important to the tuning of the rails/driver as the weight of the rails itself.

Any thoughts/advice BESIDES send the job out to someone else?

Thanks again..

Please describe parts and how supplied to feeder.

You are correct under many circumstances part mass isn't a big deal.

Sorting, orientation, and thru-put is.

Depending on several things the whole track does not have to vibrate.

You may want to simply change tracks as opposed to adjust track rail spacing, particularly where turns and elevation changes are involved.

Ag

The barrels are plastic syringe barrels.
The customer already has the vibratory feeder bowls with the tooling. There needs to be no elevation changes. Just provide a path from the feeder bowl to the assebmly station.
No turns, curves or elevation required.
Just need to provide a buffer, delivery, and "head pressure" to ensure proper stripping/escapement operation.

Is it possible to use a neoprene belt and plastics? If so, side-ways mounted cleated belt makes sense for the barrels.
If not, they make stainless steel belts. With the small caps, and a belt, you would only need to guide them with rails. I can't remember the company that makes stainless belting, but they have ads in most of the trade rags. (Motion System Design, MFG Engineering, et)

Check out Automation Devices in Fairview,PA.

CAll and talk to someone in their engineering dept.

Tony,
Thanks. The purpose of the feeder is not only transport, but also buffering, head pressure to the escapement. I'd need an escapement to feed into a segmented belt, and need to ensure I had a part ready to insert into the belt when the pocket became available.
Thus, the same problem to solve, maybe using a linear feeder, And then feed it into a belt.
Unless I misunderstand.

Harry,
I talked to them, and still have a few questions.
They wanted me to send them the finished rail, so they could tune the driver to the rail.
So, I wouldn't be able to try out any ideas until After I built the rail, and sent it in....
A bit of a catch 22 unless this was my N'th job of this nature.

Thus the questions...

I may get a used driver form ebay, and try to tune it to an experimental rail as I try stuff.. The customer should get new and or Known Good parts in the finished machine.

Now, for some info on tuning the driver to the rail...

Maybe I misunderstood. I thought the parts were coming out of a vibratory separator and needed to buffer with head pressure to your machine. If that is the case, I was suggesting flat stainless belt conveyors. You'd only need guide rails. Total head pressure would depend on the combined buffer weight and friction of said weight against the belt. Forget the cleat idea after your last post, just flat belt conveyors. Worth looking at, as it would be easy to do.

Linear Vibrator

Hi
Check out Elscint - BLOG Area | It has got a lot of information on vibratory feeders. It might help you. I personally feel you should get this done from an expert rather than wasting time on trial and error.

Regards,

Monish

Building Vibratory Feeder

At work we build our own tracks to mount on top of feeder drives from Rodix. We tend to use these Multi-hanger feeders. We have used some of the "standard in-line", but I find them to be harder to set up. There is a good chance I think they are harder only because I have more experience with the multi-hangers. To run them we try to run them on these feeder controllers. They are the cheapest way to go, but they require tuning the track to run at either 60 or 120 hz. The tuning is done through a combination of the mass of the track and how stiff the springs are. The other way we go is to change to a variable frequency drive, like this. With the variable freqency drive you can quickly find the drive frequeny that gives the best feed rate.

On vibratory drives, the best through put happens near the natrual frequency of the drive. The goal of tuning is to find this drive frequency. If you use the first type of fixed frequency drive, you need to adjust track mass and spring stiffness until the natural freqency is close to 60 or 120 Hz. This may take a couple of track revisions to hit. If you are fixed on the track you need and can't get the natural frequency where you want it with springs, the more expensive variable frequency drives allow you to move the drive frequency to the natural frequency of the track.

Having said all that, there is a black art to vibratory drives. It is much easier to tackle if you have someone with experience that can look at your tuning and make suggestions.

If you are going to deal in vibratory drives, go ahead and jump in. They can be tricky, but it is managable.

Adam

Monish,

Thanks for the link to your blog.
Very informative.

Adam,

Curious about Rodix. I called them and tried to ask questions about feeder designs.
They told me to talk to someone else, find an equipment designer and let them do the design. They did not seem to know any specs for the drivers, expected feed rates, motion travel etc. I started to think that they only design and build the electrical drivers, but not the vibratory hardware, but only carry it as a sideline to their drivers.
Of course I might have gotten an electrical designer, who did not think to pass me off to a mechanical designer. I don't know.

About all I can do is make a track and try it out.
Most of my original questions remain.

Should I rough up the tacks for better traction to drive the parts along?

Are there any books about stripping the parts off of the tracks?

(This is hard to explain, but Very easy to see visually... )
I've seen many parts where the part can be supported from the bottom, like a bottle cap, for example. In that case, the continuous motion machinery can have a tapered lead in to the station, and catch the part as the pocket comes by.
With a part that needs to be "dangled" it cannot be tapered into the pocket. Since the part will need to be dangled until it is grabbed by the pocket, the rail cannot extend into the area where the pocket will rotate past.

So, for a dangling part, I don't see how to have a lead in and let the part feed into the ramp until the pocket comes past, ( pockets with a saw tooth shape) to grab the part that has ramped into position after the previous pocket.
Parts sitting on the "floor" can very easily be ramped in with that saw tooth shape for the pockets..
With dangling parts, not so much, how can they ramp into a pocket, and be supported (dangled) by the rails, if the rails will then be in the way for the filled pocket to then pass by?

Thanks again, keep the ideas coming.

3t3d said:

Adam,

Curious about Rodix. I called them and tried to ask questions about feeder designs.

Click to expand...

I have never called and tried to get track design info from Rodix. If you look on their website at the application notes for the tracks they have the technical information to set up the drivers. This is the link to one of the app notes.

When I had some electrical questions about some of the coil properties I had to go through 3 people before I found the person who had the answer. With general questions like you have, it may be difficult to find the right person to sit down and explain everything to you.

3t3d said:

About all I can do is make a track and try it out.

Click to expand...

Yes, that is about the size of things. Use the info from the application notes above and design your track.

3t3d said:

Most of my original questions remain.

Should I rough up the tacks for better traction to drive the parts along?

Click to expand...

I personally haven't seen that done. All the tracks I have seen are just the finish from the milling machine with any burrs removed.

3t3d said:

Are there any books about stripping the parts off of the tracks?

Click to expand...

None I am aware of.

3t3d said:

(This is hard to explain, but Very easy to see visually... )
I've seen many parts where the part can be supported from the bottom, like a bottle cap, for example. In that case, the continuous motion machinery can have a tapered lead in to the station, and catch the part as the pocket comes by.
With a part that needs to be "dangled" it cannot be tapered into the pocket. Since the part will need to be dangled until it is grabbed by the pocket, the rail cannot extend into the area where the pocket will rotate past.

So, for a dangling part, I don't see how to have a lead in and let the part feed into the ramp until the pocket comes past, ( pockets with a saw tooth shape) to grab the part that has ramped into position after the previous pocket.
Parts sitting on the "floor" can very easily be ramped in with that saw tooth shape for the pockets..
With dangling parts, not so much, how can they ramp into a pocket, and be supported (dangled) by the rails, if the rails will then be in the way for the filled pocket to then pass by?

Thanks again, keep the ideas coming.

Click to expand...

So you're going on to a continuous dial? How do you plan to enter the wheel? Tangentally or radially?

If tangentally: You will need a feed screw or something else to line the parts up with the pockets. If you let the wheel do the stripping you will likely have a problem with shearing the parts off, or otherwise jamming them.

If radially: Vibratory probably isn't going to be quick enough. With dangling parts you won't be able to use a saw tooth wheel. You will want to use a wheel with 'C' shapped pockets to carry the parts. This requires getting the parts in FAST!! I would put a number of air jets on the parts where they enter the wheel to get them in quick. In fact, at 180 ppm I would strongly consider ditching the vibratory all together and just run air tracks. Parts flow faster, easier to tune, less clearance at track joints, you still get buffer accumulation. The only down side is that you with likely end up with more power consumption on the machine.

If you do get this working without air jets, please let me know how you did it.

Adam

Adam,
Thanks!

Getting the parts into a continuous dial would be "puzzle" (!)
I am going to try an indexer to dwell at the input station to allow the parts more time to get into the pockets. The indexer has a 270 degrees of motion, and 90 degrees of dwell.
At three parts per second that is 1/12 of a second to get the parts into the pocket.
At 1" diameter part, that is a burst of 720 inches per minute as it enters the pocket.
Average( sustained) upstream speed needs to be 180" per minute. Automation Devices suggested to expect to achieve about twice that.
Trying the air jets seems to be a popular suggestion to get into the pocket.

The dial itself does not need to be indexed, just dwelling to fill the pockets.

Thanks for understanding my question about "dangling" parts. I was not sure how to describe that.

I will have some linear drivers in this afternoon to try out, and will be making a fake dial with pockets to start to testing getting the parts into the pockets.

check out Roboshop in Syracuse NY. they make a vibratory feeder that uses a astroturf material for one way motion. very neat.www.inmotionconveyors.com

I am a little late getting in on this discussion, however I am doing this right now. I am feed and tracking multiple sizes and styles of syringe bodies along with the plunger rods for each body in two different feed systems. I've constructed each from start to finish. There are some definite advantages of having a working knowledge of vibratory feeders and "part handling" techniques as a whole. There are numerous variables which can make the task at hand seem next to impossible but just as many that will enable you to succeed. It's only a matter of finding and utilizing the combination of that will get you there. Often, the construction of a project like this will not take you in a straight line to the finish. You will have to back up, scratch your head and cuss a little (or a lot) the find the right combinations that make a complete and functional feed system. Your customer or boss will want this to work very well and without constant operator assistance. Now that I've said all that, did you get it done?

I used to do a lot of work with FMC vibrating feeders, we refered to them as Syntron feeders and used the to handle components in the pharmaceutical industry. They would make any custom parts you needed. With experience it was easy to pick up on the techniques to apply for a particular application. I would give them a call and talk with an application specialist, what you want to do has been done many times.
Good luck,
Don