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Coin-op machine please help for free or fee

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ttelgrande

New Member
I need to build fifteen coin-op timer mechanisms for my internet cafe. I have the mechanical part just about ready, but eletronics always stump me. Logic comes easy but the sizing of resistors and capcitors is really beyond me. I have specs and part numbers for parts below. I could also attempt a drawing . Help me if you can or put me in the right directions please.

supply voltage is usb 5v

2 - slotted infrared optical switches (transistor type, normally on) HY860N

1 - JFET transistor ( to reverse on state of the first slot switch) no idea what to buy

1 - clock 1.2v (to remove the first coin in line and trip second slot switch to turn off timer)
clock has a disk instead of hour hand with projections to push coins or trip slot switch.

1 - voltage regulator (to provide power to the clock) LM317T adjustable regulator

1 - 5v relay ( to turn on/off computers and playstations)

resistors for voltage regulator and transistors
capcitor to protect against the coil in relay

The circuit works as follows:
coin enters first slot switch, with the aid of the JFET turns on the clock and the relay
clock turns and pushes first coin in line off the track, second coin advances (if any)
clock continues to turn, when it trips second slot switch, the mechanism goes off

Thank You for your help.
 

alec_t

Well-Known Member
Most Helpful Member
I have doubts as to whether the clock will be (a) strong enough to move the coin as you plan and (b) sufficiently durable.
Have you considered using a solid-state timer driving a solenoid or small DC motor?
 

ttelgrande

New Member
thats interesting. i need help with the circuits and you give me advice on the mechanical. yes the clock is strong enough. i have a prototype i made and the clock worked fine for two months. as for the slugs one is exactly the same diameter it could pass, but where i live the slug would cost more than the coin it substitutes. i live in costa rica and the coin has a value of 20 cents while the slug or washer would be worth 50 cents or more. and my business is repeat customers most of which are friends. the coin-op frees me up to do other things. internet is not that profitable. for those that have interest in the mechanisms, i will gladly post pictures when complete. the coin acceptor is a design i found on a diy sight. it rejects all coins bigger ans smaller than the target size.
 

ttelgrande

New Member
this is the diy site for the coin acceptor

http://josepino.com/howto/coin-operated_machine_II

i am using plexiglass and a bit different manner for the coins to enter so as not to let someone just put a stick in and trigger the slot switch. the clock is your standard cheap AA battery alarm clock with the hands removed and the rest is the slot switches and the relay.

but please help me with the circuit, i can do a prelim drawing but nee help with the resistors and capacitors.
 

ttelgrande

New Member
here is my first attempt at the circuit, i got the resister sizes on the voltage regulator from the seller on ebay. if he is correct then the next thing is is the voltage correct for the slot switches, and if not how do i correct that and do i need a diode or capacitor to limit the kickback from the relay coil. thanks in advance for your help and i will post the specs for the slot switches in a few minutesView attachment 65360
 

ttelgrande

New Member
here are the specs on the slot switches. the seller said they do not work with 5vdc, but i found another thread that indicated that maybe a resister could solve that problem. wish i was smarter on these things but i am really good at finding things on the internet if you need help with that
Output Type Photo Transistor
Peak Emission Wavelength 940nm
IR Diode Forward Current 50mA
IR Diode Reverse Voltage 5V
Transistor Power Dissipation 75mW
Transistor Collector Current 20mA
Photo Transistor Collector-emitter Voltage 30V
Photo Transistor Emitter-collector Voltage 5V
Diode Power Dissipation 100mW
 

ronv

Well-Known Member
Most Helpful Member
The circuit works as follows:
coin enters first slot switch, with the aid of the JFET turns on the clock and the relay
I understand starting the clock with this sensor. Does the coin stay in the sensor or do you need to "remember" that the coin went thru the sensor?
clock turns and pushes first coin in line off the track, second coin advances (if any)
Not sure I understand this.
clock continues to turn, when it trips second slot switch, the mechanism goes off

This makes me think the clock turns on with the first sensor and off with the second, but I am still not sure.

I will look now at the values in your circuit.
 

ronv

Well-Known Member
Most Helpful Member
Add 150 ohms in series with sensor diode to limit the current.
On the LM317 - Ground the ADJ pin and change the 1100 ohm to 120 ohms. This will give about 1.25 volts out and come close to the minimum load current of 12 ma. maximum.
Add a diode across the relay coil with the anode to the ground side a 1N5717 would be a good one ig you can find one.
We need the spec on the relay and the clock to see if the sensor can supply enough power to run them.
 

ttelgrande

New Member
Thanks so much for your help. I am 57 yrs old and this is my first electronic circuit. I live in Cost Rica and when I get this working, my internet cafe should be almost totally self-serve.

To review the mechanical functions. The clock is fitted with a disk that has five arms (12 minutes each) that replaces the hour hand. all other hands are removed. Then coins enter on a ramp and triggers the first slot switch. ( As the switch is normally on I need the JFET to reverse the state to normally off. ) This in turn, turns on the clock and the relay. The arm on the clock disk leaves the second slot switch and at this moment both slot switches power the clock and the relay. The clock disk continues turning and pushes the coin off the track with the arm. If there is another coin, it will roll into the first slot switch and keep the circuit running past the point of the arm entering the second slot switch. If there is no second coin the arm advances and cuts power as it enters the second slot switch. As long as the customer feeds coins the system stays active. 12 minutes per coin. With four arms on the disk the system would go 15 minutes per coin etc.

If I understand your instructions correctly the new drawing should indicate the changes.

I do not know how much current the clock uses. It is the standard AA battery clock that hangs on the wall everywhere. As the battery last months and months the current must be very low. It does use a 1.5vdc battery. So I may be mistaken about the voltage. But I do know it works fine with a rechargeable 1.2v it has a quarts crystal as well.

the relay is Songle Relay ISO9002 SRD

Voltage 5 VDC
Current 90 mA
Resistance 55 ohms
Coil rated voltage: 3-48VDC
Coil power: 0.36W, 0.45W
Rated load: 10A 125VAC

I do not find the diode you indicated available on Ebay and I am still in doubt about the JFET.

Thanks
Terry
 
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ronv

Well-Known Member
Most Helpful Member
Coin machine

Very clever. I think I understand.
I think this will work for you. It switches ground instead of +5 so the FET is easier.
 

ttelgrande

New Member
thank you
i dont understand any of this
need to study it for a day
the idea to switch ground makes the layman mind crazy but i am sure you are correct
tomorrow i will have my questions
again thanks
 

ttelgrande

New Member
i looked at it again and i think i get it but it is more complicated than my experience level
need to sleep on it to understand how to build it
thank you so much
good night
 

ronv

Well-Known Member
Most Helpful Member
I think you know the 317. It supplies the clock with about 1.4 volts now.
U4 or U5 can supply ground to the clock and relay turning them on.
U4 and U5 turn on when the gate is positive.
U4 gate is positive when the sensor is blocked. (U1 is off)
U5 gate is positive when the sensor is not blocked. (U2 is on)
 

ttelgrande

New Member
Hi got a bad cold so I could not put my attention to this yesterday. Good idea to change the circuit to ground switching. Keeps the voltage regulator out of the switching loop. I pretty much understand everything but have a couple questions and an observation.

Does R5 supply power to gate at V4 when V1 is in the off state and V1 grounds the gate at V4 when V1 is in the on state? This is a bit confusing for my primitive mind. hehehe

What does R7 do? not clear as to its function.

From what I understand, if the LED in V1 were to fail that would leave the system in an always on state. I don't think this is a big problem as LEDs are very reliable, but I would be providing free internet until I detected the faulty LED.

Do you think 2N7002 has enough current capacity? It handle 115 mA whereas the 2N7000m handles 200 mA and is about the same price.

Can't find the 1N5717 Diode. Could I use a 1N4002 1A 100V Rectifier Diode instead?

Would the resistor at R3 be something like this 120 Ohms OHM 1/4W ?
And at R5 and R7 something like 5K1 5.1K Ohms OHM 1/4W 5% Carbon Film?

My only other question is what do you predict the voltage at regulator to be now?


Thanks for the help. After I hear back I will order parts and with luck, in a month build the first one.
 

ronv

Well-Known Member
Most Helpful Member
Does R5 supply power to gate at V4 when V1 is in the off state and V1 grounds the gate at V4 when V1 is in the on state? This is a bit confusing for my primitive mind. hehehe

Right you are.

What does R7 do? not clear as to its function.

It makes sure U5 turns off.

From what I understand, if the LED in V1 were to fail that would leave the system in an always on state. I don't think this is a big problem as LEDs are very reliable, but I would be providing free internet until I detected the faulty LED.

This is true, but reliability is very good.

Do you think 2N7002 has enough current capacity? It handle 115 mA whereas the 2N7000m handles 200 mA and is about the same price.

The 2N7000 would be better.

Can't find the 1N5717 Diode. Could I use a 1N4002 1A 100V Rectifier Diode instead?

Should be okay

Would the resistor at R3 be something like this 120 Ohms OHM 1/4W ?
And at R5 and R7 something like 5K1 5.1K Ohms OHM 1/4W 5% Carbon Film?

Should work fine.

My only other question is what do you predict the voltage at regulator to be now?

I have the voltage now at 1.375 volts.

Good luck with the project! Come back and tell us how it works.

Hope your cold is better.:mad::mad:
 

ttelgrande

New Member
Thank you, big big help, on my own I am sure that would have taken weeks.

I am off on a shopping spree. Ebay here I come.

I will send you a video of the finished project.

Give me about 6 weeks, it takes time to get things in the mail.

a little whiskey doesn't make the cold go away, but .......

hasta luego (later)
 
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