Fruit Polishing Machine. Help for a student

[mrdavide]

Fruit Polishing Machine. Help for a student!

Hey guys.
I’m a student from Politecnico di Milano, where I’m doing a graduate diploma in Design & Engineering. I have a problem related with the mechanic of my project: I am designing a machine to polish fruit in home environment (the machine should be small-max dimensions like a microwave). The problem is to find the better way to gently rotate the fruit in order to clean all the surface of the product. The machine should treat all fruit except bananas, grapes and those that are too soft and small (such raspberry, strawberry, ecc…). I attach my hypothesis so you can figure the problem better.

1-to use rollers, as it happens into an industrial environment or in the medicine field. I have already tried this device and it does work. The problem is that I’m designing a machine which has to be user friendly and this method doesn’t look like it's user friendly!
see image 1

2- To use a device like a salad spinner or a potatoes peeler but with a brush plate instead of the cutting parts. The problem, I think, is that the fruit cannot rotate properly, especially fruit like pears. See here: http://shop.scotsman.com/I-CC-D2983-UTN-2/automatic-potato-peeler.htm


3-To use a device similar to potatoes peeler but with roller on the spinning plate. See sketch 2. The rollers can be long or small, or more like wheels.


4-Is it possible to design a spinning plate with a shape that allows fruit to rotate without any other devices such brush, rollers, etc…? I think the shape, the spinning speed ω and the acceleration ω’ should be consider very carefully to allow the fruit rotation.
See skatch 3

Which one do you think works better? Why? Any suggestion is appreciated.

Maybe the problem looks easy for you…but not for me!

Thanks for your time
ciao

 

[chayced]

What about having a cloth belt that goes in a V between two rollers. The fruit sets in the bottom of the V as the cloth moves. Just a thought.

 

[Danger]

That's not a bad idea at all, Chayced. It led me to wonder, though, if you couldn't just use a couple of counter-rotating horizontal cylinders instead. It would have the same effect, but without the complication of using a belt.

 

[mrdavide]

Hey guys, thanks for your replies. I am thinking to use the rotating mechanism, such we find in a electric potatoes peeler. It looks easy and simple. The idea of Danger is not bad at all, but I am trying to design a product which is small and maybe your design will make it a little too big.

Anyway this is the new question:

How does a electric peeler work? In particular how is it able to rotate the fruit? The spinning action itself I think is not sufficient…maybe for the friction on the cutting plate? In a potatoes peeler the only part that rotate is the plate with the abrasive-cutting coating, while the bowl is firm…

Any knowledge will be appreciated.

Ciao