About Multi-coin Acceptor

multi coint acceptor

Can anybody tell me what characteristic of the coin is checked after it is inserted into the multi-coin acceptor.

metal content?
diameter?
thickness?

and how does it work?

thx!

Dear Nicholas,

Most machines weight the coins.
Every coin has different weight, so by weighting the coin the machine "knows" what coin was inserted.

Easy does it :wink:

Regards,

Pazam

The electronic detector work with two oscillators and coils.The coin sit between the two coils. The output frequency depend from diameter, metal contents and the surface roughness.

Sebi said:

The electronic detector work with two oscillators and coils.The coin sit between the two coils. The output frequency depend from diameter, metal contents and the surface roughness.

Click to expand...

Can coins of different contents and diameter make a same frequency? If so, how to distinguish them?

thank you both.

I do work with these units. I repair coin operated machines.
They are very difficult to cheat. The most modern ones have three sets of coils. They measure metal composition, size and speed.
The most competent ones can decode 16 different types of coins and even sort them into different output lanes.
If the coins passes the tests does a small solenoid open or close a gate or diverter to let the coin pass into the coinbox. The credit pulse is generated first when the coin has passed the gate and an infrared beam.
The sensitivity and wideness of acceptance is set when the units are programmed.
If someone tries to manipulate does the unit stop working for a short time.

Frasse

Frasse:

Can you tell me in a little more detail about what it really does to measure the size of a coin ? thank you.

Nicholas

It measures the time it takes for the coint to pass through the acceptor. Even if the coin is of the right size (diameter), if it passes too slowly it will be rejected.

If we are talking casino coin acceptors, many of the coins also have special patterns that are detected usign IR optics, but this is another story.

Zacharsky

Hmm,

I heart a story.Once upon a time two guys get original coin and print its template to plaster paste.Then pull out the coin from plaster and let it dry.Finally they put conductor solution to voids of coin and let it freeze They cheated many drink machines with these ice coins.
So, i understood that it is not only related with conductivity and size eh?
Is there any way to cheat machines? But don't tell the way just "yes/no" "there is easy/hard way"

Analyzer

It really depends on the coin acceptor type/model. Most casino acceptors are very sophisticated, they DO check for certain material properties, size, patterns (IDX acceptor) etc. The setup (programming) procedure includes teaching sequence, where the acceptor learns the properties of the coin. That includes passing the coin multiple times through the acceptor, so that it can "learn" certain properties. This allows the acceptor to be reprogrammed if the coins have to be changed.

Again, generic soda machines probably don't have that level of sophistication, but I cannot help you with those, since my experience is exclusively with casino acceptors.

Zacharsky

PS. I remember using some Chinese coins instead of US quarters in vending machines, but that didn't work for newspaper machines.

The different coils will act as a series of metal detectors. The signature is different depending on the diameter, metal composition and thickness. The time it takes between the signatures to reach the processor will tell the speed of the coin. All these data has to be within the set limits which are set when the coin acceptor is programmed. This is made by the use of a special software (running in PC) and a serial cable. The wideness of acceptance is set by widening the "window" of acceptance before uploading the settings into the acceptor. We use as many coins as possible during the programming to get a good acceptance without widening the settings too much since when they are manually widened will the acceptor become more acceptable to "fake" coins.
I have seen a number of attempts to cheat these units.
Making a mould and creating a copy in lead or tin. Glueing two coins together with the same size but not the thickness in a attempt to create a more valuable coin. And of course the fishing line.
The problem of creating fake coins lies in the fact that many real coins are made in strange mixes of metal and in some cases have a thin core of lets say copper and the outher sides of nickel. This will cause a signature which is very difficult to replicate.

Frasse

somebody knows some machin that accept bulk of coins at same time sort them an count them?

Thanks in advance

Enrique Ceseña

somebody knows some machin that accept bulk of coins at same time sort them an count them?

Thanks in advance

Enrique Ceseña

Is it something like this you are looking for?
**broken link removed**
These machines are quite expensive and mostly only found in banks.

Frasse

I've designed a coin accepter for Ginsan company. It used two coils with the coin slot between them. A ~20Khz oscillator would drive one of the coils. A receiver would measure amplitude and phase of the coupled signals. That information can tell shape, metal type, and multicompositional metal coins. Mine was done with a simple PIC 16C71. It could be programmed for four types of coins.