What does the button do on a CH-926 coin acceptor?

Community General Discussion
1

I'm looking for a coin acceptor for my arcade project.
The coin acceptor CH-926 seems to be famous on many internet sources and videos. There are a lot if videos that demonstrate the working and programming of the device.

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But they don't mention the blue pushbutton on the coin acceptor (The button with text "Please insert coin"). The manual says the button is for releasing blocked coins.
But I don't understand what they mean by "blocked coins". As far as I know, a coin matches with any coin it is programmed with (is accepted) and falls through, or if it's a wrong coin it spits it out into the lower coin slit.

If you are a user of the machine, when would you need to push that blue button?

I actually also have another question not about the coin acceptor but about how to handle payment:
Say, you have to put in coins to buy credits on the arcade machine. And say a credit costs €1 and the coin acceptor is programmed to accept coins of €2, €1, €0,50, €0,20, €0,10.
Now an example situation: the user inserts a €1 coin, the machine counts 1 credit on the display. Now the user inserts a coin of €0,50, and a coin of €0,20 and suddenly realizes he has no more coins in his wallet. The 70 eurocents (coin of €0,50 and €0,20) are payd too much, and he gets nothing for it. I've actually never really thought of this and how do arcade/vending machines handle this?

2

That would be a bent coin that lodges in the pathway. Or could be coins with strings on them.

3

That blue 'reject' button physically opens the flight deck to allow jammed coins to fall downwards and forwards to come out of the reject coin slot.

Here is a view looking from the other side of the coin acceptor:

CH-926 Rejrct Button
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4

Thank you for this answer with picture.

5

There is a third option - jammed coins.

Coins can get jammed for a number of reasons

  • customer puts coins in too fast, and they get jammed side by side.
  • drink vending machines get contaminated with syrupy/sticky liquid. - coins get stuck
  • bent coins - I don't think there are actually many of these.

That blue button is to clear these jammed coins.

6

...a picture is worth a thousand words.