building a sorter - divert devices?

[monkeyhead]

so i'm getting geared up to build a small sorter. it's pretty straight forward. 7 sorts, 1 kickout lane. simple message passing logic. i've got everything planned out, but the one thing i'm not sure how I want to handle are the physical diverts for each sort.

It's gonna be low speed. 30 pkgs/min rolling down a conveyor at 90ft/min. i was thinking about just using a plain ol' air cylinder with a pusher plate setup, but i started thinking about the noise and how air cylinders tend to have limited lives in the environment i work in and want to consider some other options.

i'm gonna be on a pretty tight budget though so i don't think i can afford pop up roller diverts. Anybody have any good suggestions? the packages are gonna be small dvd sized packages.

 

[rsdoran]

When I worked at the plant bagging a cemetitious product we had to use a motor and chain drive pusher, it may not be cheaper than pneumatics but if the objects are heavy and the environment harsh it can be more durable. The offset to doing this is that usually you have to build a bridge over the conveyor line that has to be higher than the packages, it is simple and effective though.

 

[brucechase]

I use the transverse roller top belt from intralox ( http://www.intralox.com/ ) along with an air actuated kicker plate. My products are a lot larger though (tires), but it works so good that I've gotten rid of all my pop up diverts (saves a motor/starter per diverter).

 

[Rod]

Monkeyhead,

What is the mass, physical package size, distance the 'kicker' must travel, the time the diverter must perform in.

DETAILS ya know.

It could be time for a Bimba cylinder

Rod

 

[monkeyhead]

i covered most of the details in my original post. dvd sized packages traveling at 90 ft/min being introduced at 30 items a minute. I'm looking for alternatives to the bimba cylinder approach. I have a personal distaste for bimba anyway.

two things i didn't cover were conveyor width: 12" to 18" and package weight: <5lbs. this is gonna be a small system.

Ron and Bruechase, thanks for the tips. Time to put on my research cap and get to work.

 

[Eric Nelson]

I question why air cylinders don't last in your environment. They should last for millions of cycles.

One idea is to mount a cam off the conveyor drive to convert rotary motion to the linear motion you need for your pusher. Make it so the lever arm (cam follower) is spring loaded against the cam, so you can lock it out (inhibit pushing). We've done this on numerous machines, and it works well. Here's a quick drawing. Yeah the drawing sucks, but it should give you the gist of it...

The little lockout arm can be moved with a small electric solenoid. The dashed lines show the unlocked position. You unlock it only at the top of the cam lobe, but you only have to fire the solenoid until the arm moves bit. It has a lead-in so it will automatically grab the lever arm pin when it comes back.

A big advantage of this is that pusher speed is dictated by conveyor speed. Increase/decrease conveyor speed, and the pusher matches it. Of course, you could also drive the cam with a separate motor.

When possible, I prefer to remove "good" parts rather than rejects. That way, if the removal mechanism fails to operate, the part gets rejected. IOW, when something goes wrong, the best scenario is to reject good parts, rather than ship bad ones to the customer!... :nodi:



-Eric

 

[Doug_P]

What about a Sliding Shoe sorter?

 

[monkeyhead]

As per usual, thanks for the ideas. I'm gonna pass Eric's drawings on to our machinist/mechanic and see what he can come up with. Don't know if we have the time to build them oursleves, but I like the idea.

The air cylinders should last, but our maintenance team is awful with any type of pneumatic preventative maintenance. I can't even begin to describe how many times i've magically fixed machines by backing off the amount of air pressure or cleaning some neglected gummed up cylinder. That's sadly my motivation for checking out other options.

But anyway's you guys have as always proved to be an invaluable resource. Thanks a ton.

 

[Eric Nelson]

What about a Sliding Shoe sorter?

Those are very cool, Doug. I've seen similar designs where the actual tabletop shifts. These look very appropriate for MH's application. I wonder how much they cost though...



-Eric

P.S. There's a video of them in action at the bottom of THIS page. The Quicktime version is much clearer.

 

[Del Monte]

Hey Eric, interesting drawing.

Did you design that?

Can you recommend any good restaurants in northern NJ, near the Garden State Parkway?

Del

 

[Doug_P]

...I wonder how much they cost though...


...QUOTE]
More, I'm sure.

However, the maker states that the conveyor can be delivered with a functioning control system. Once it's running, you just give it a product and a destination and then forget it. A plus if you don't want to, or can't afford to work out the induction/tracking/divert logic.

 

[Eric Nelson]

Can you recommend any good restaurants in northern NJ, near the Garden State Parkway?

Planning a visit, Dell? I can't recommend any restaurants, as I rarely dine out.

There's always the fast food joints at every rest stop on the Parkway...



-Eric

 

[Del Monte]

There's always the fast food joints at every rest stop on the Parkway...

The idea is NOT to eat fast food. Since I gave that up I have lost more weight than I would care to admit to. I do like fruits and salad, but a great staek isn't out of the question. Not to mwntion that I will be on expense account. I will be in northern New Jersey about ten days, then Columbus for three days, Chicago area about three days, then escape back home. I have my favorite places in Columbus and Chicago, but haven't been to New Jersey. Places that I new in NYC are probably long gone, but I don't even want to go there. I was told I could look for Jimmy Hoffa in my spare time. That sounds like fun?

Del

 

[Johnny T]

I once did some work on a line that was making DVD boxes and video boxes.

We used blasts of air to reject.

It was air conveyor they were running on (I worked for Ling Systems at the time - now defunct - but they used to make air conveyor for PET bottles etc)

Not sure if it would be effective in your situation but thought I'd chuck the idea into the mix...

 

[monkeyhead]

thanks Johnny!