Coin sorting using lego

[swatcat]

Hi,

I am new to Eurobricks so hi :) I am in the process of building an ATM machine, the bit I am struggling with is how to only dispense one coin (e.g. 10p or 20p) at a time, 2 x 20p's are equivalent to 1/3 of a brick high. Does anyone have any suggestions for techniques to use please?

Thank you in advanced :)

Swatcat

[JopieK]

Welcome to EB :) why don't you also introduce yourself! You could make a sieve of course. If it doesn't need to be all LEGO, check out the coin acceptor of Sparkfun electronics.

[dvsntt]

You can use the a panel piece to get better precision. I think it is half the width of a tile.

[swatcat]

Thank you, I am 35 years old and from the UK, been a Lego fanatic all my life My background is software development and engineering so I want to build mechanical Lego :)

My main issue with the coin is how to make a device that pulls only one coin as two make 1/3 brick high.

[62Bricks]

Are you looking for a way to make a gap that is more than one coin thick but less than two? If so, here is one possible technique.

You say two coins are the same width as one-third a brick height, which is one plate. If you convert to LDraw units (LDU), that is 8 LDU. So one coin is approximately 4 LDU. you need a gap greater than 4 LDU but less than 8. The lattice fence piece has a center section that is 6.67 LDU wide and can be used to make a gap of this width:

[swatcat]

What I am trying to do is have a way to have only 1 coin (which 2 are size of a plate (1/3 of brick), thank you 62Bricks I will give that suggestion above a try.

[62Bricks]

If you need a gap that is exactly one-half a plate thickness, which is 4 LDU, it is pretty simple. This is one technique: