Bottle Feeding Screw

What type of software do you have, Solidworks, Inventor, ect...?

Also there are company's that supply these feeder screws.

As far as design info. they are out there, what is you knowledge on this industry, do you have a degree or experience? How much experiences? Is this an actual application in industry, or a homework assignment?

You have to realize these questions need to be asked if not to delivery the required information, but at least point you in the right direction.

p911

Phoenix thank you for your concern,

i'll answer your questions one by one

1- I use Autodesk inventor 2010 pro

2- I know, but i want to get involved in the design so have them manufactured in-house

3- I didn't find any information out there, only quotations, i'm an industrial mechanical engineer with 5 years experience in the design of conveyors and packaging machinery, especially end of line machines (packers, stackers...). The screw is a real world application, i used to use star wheels but now i want to get hold of the theory behind screwfeeders theory since this will open lots of opportunities and adds more flexibility to my machines especially in change overs.

I'm ready to answer any question that might arise concerning this subject, i don't want anyone to do the job for me, i just need information on which i will base my study, calculations and development.

So i would really appreciate if you can help me, or at least point me to the right direction, i've seen some very exotic screws on our customers sites, and there must be guidelines to those designs...

Thanks again for your concern,

Regards,

wasaadeh:

Great, no we wouldn't do this job for you but we love working with you. Pointing you in the right direction at least.

I may have some PDFs that you can use to develop a base line, I have to see if these pdfs is public domain, Rgis will give you a base line. As a OEM, there usually is not a "formula" but amore of empirical data (trial and error) for this.

But with a solid baseline design/understanding you lower your risk.

I'll look for the PDF's

The other issue, it sounds that you are have problems creating the progessive screw with inventor, Is that true"

p911

unfortunately, inventor does not have a built in function for a variable pitch helix. i'm experimenting some workarounds, but that's for later, the first phase of my project is to create the screw with a constant pitch.

The starting of the screw is giving me headaches.

i created a cylinder, cut it with a special profile using coil command. all is fine by now.

then i have to reduce the radius of the last thread to "melt" into the center shaft. And that's where the dancing starts...

Then i must think about the manufacturing approach.....

Regards,

Here is some information real basic, my computer crash but you need your bottles as a start.

Timing Screws

If one has a steady stream of empty plastic bottles being constrained by guard rails while being transported along a relatively slippery conveyor belt, and there is a movable stop that makes them bunch up like bumper-to-bumper traffic on a holiday weekend, then it may be difficult to pull one bottle at a time from the pack to be properly spaced under a filling machine. Years ago someone very clever determined that if a variable pitch screw was custom made for a particular shaped product, then one could take the bumper to bumper group and define some order to them.

The output of a timing screw can be directly to a flighted conveyor, to a pallet, or any other device that will keep the product properly spaced while being processed. Each timing screw is custom made from either your CAD drawing of the part, or from several part samples.

Inventor can be a dog for this where solid works excel at. , One thing that I do is, Solidworks has an excellent routine for this, by also creating the progressive screw, with vary little construction or knowledge of Solidworks. They offer a stimulus package for evaluation for download. Fully functional and free tutorials you may have to find download also, may take an afternoon, but this may save you in the long run, I like to also add, so you are not pirating to consider Solidworks for your project. Its I believe a 90 day trial and its still going on.

I'm not a salesman. I add this for integrity reasons, you'll be surprised.with Solidworks

look this over, use it for a start, if your still having problems or need more information, just respond.

The other issue, do you have or need the design or a machine that orientate these bottles.

p911

then i have to reduce the radius of the last thread to "melt" into the center shaft. And that's where the dancing starts...

If I recall, Inventor has issues with involute surfaces, to be able to mend them

what I have done in the bast, is make the object in sections. Id shaft, and the flites/flutes would be two separate items.

It will resemble a drill with flutes

Keep in mind the manufacturability. Of which, what will you be using to machine this?

p911

Phoenix911, i thank you one more time for your effort

unfortunately downloading and working with SW is not an easy option in my company, the back and forth communication to install a software outside the software matrix will probably take for ever.

however, my main issue right now is not in the progressive pitch, it's with the concept... how should i approach this issue. How to create the cutting shape in a way that will not tilt my bottles while dragging them, btw, in my application i have conical jars...

i already posted in the inventor forum about modeling

http://forums.autodesk.com/t5/Autodesk-Inventor/Feeding-screw-model/td-p/2700975/page/1, but i posted here to get design considerations.

In our factory we have lathes and mills, both normal and CNC. And since the part to manufacture is a kind of plastic, i can easily create my own tool, probably having the same shape of the cut...

Randall, thank you for your suggestions, but i already did that search, actually i googled every synonym of screw combined with feeding...

anyway, i think there is not much information on the net, i'll try to model some screws, manufacture some prototypes then build my own charts... old school...

i'll try to model some screws, manufacture some prototypes then build my own charts... old school...

I like that....there are no short cuts

here more.

I did a google search of "screw feed bottling filling machine video" and came up with this;

http://www.google.com/#hl=en&tbs=vid%3A1&q=screw+feed+bottling+filling+machine+video&aq=f&aqi=&aql=&oq=&gs_rfai=&fp=865508c5312c5e98

some results look promising.

http://www.kinsleyinc.com/PublicPages/Home.aspx this is a manufacture. It does not hurt to talk to them, they have the experience behind them, experience that you need. If you are still bent on manufacturing them in-house, you'll at least gain some knowledge of it.

Remember, as a engineer and a designer, you have to look at your risks and take assessment of it. The more information and data you have, the better decisions and outcome results. Nothing wrong with doing it your self, but you have to dig and invest time. As a designer of OEM, that investment comes out of your personal life.

You need to work off your bottles, understand the physics, inertias. and control them.

http://www.youtube.com/watch?v=9mUwLqQm2A4 some videos

As I stated earlier posts, allot of the design is from empirical. Very valuable.

Bottling and packaging is an art as its engineering. no short cuts.

p911

Just in case you haven't done this:-

http://www.google.co.uk/#hl=en&safe=active&q=designing+screw+feeder+in+Autodesk+inventor&aq=f&aqi=&aql=&oq=designing+screw+feeder+in+Autodesk+inventor&gs_rfai=&fp=3fa6a6fa87c20bb4

Gents,

i promised to send feed back.

Actually i haven't manufactured the screw yet, but i've had some good results by simulating on Inventor. I modeled it and sent it to manufacturing. I'll post again after testing.

Here's how i proceeded

1- Create a cylinder having the same external diameter of the screw

2- Cut a coil with the needed pitch and profile

3-Copy the same cutting profile and create a coil over the last thread of the screw but this time with a higher pitch

4-Create a third coil over the last thread with a smaller pitch

Steps 3 and 4 will cause a smaller "fin" in the last pitch. and this gets handy when the screw is turned "lathe" to create the entry phase.

Now to create the beginning of the screw, i revolved-cut a polyline starting from the internal diameter of the screw and ending at the external diameter.

That polyline starts with a line parallel to the screws axis, then reaches to the external diameter via an arc tangent to the first line. The length of the line and the diameter of the arc where estimated by trial and error.

Hope that helped.

Cheers,

wasaadeh, have you had any success designing a feed screw? I am also attempting to develop a method for my company to design and manufacture our own feedscrews to convey bottles into packaging machinery.