Need help

[Steve b]

hi all I am wanting to start a project similar to one I have seen on you tube it is essentially a Coke can dispenser I will link below I would really appriciate if any one was able to tell me what components I would need for the circuit and how I would wire everything together thanks for your time I will ensure I post updates on how it is going the video does show a brief look at the guts of the machine

 

[KeepItSimpleStupid]

the hard part to see is that he's using a "spring pin", somthing like this https://www.searspartsdirect.com/pa...m_medium=cse&utm_term=2816001SM&sid=SPDxGPROD on the hub of the gear to "stop the motor". I had to watch the video a number of times to see it.

The "non coin" switch is designed to "stop" the motor at one particular spot. The "coin switch" shorts the "stop switch" momentarily thus causing the motor to move in the stopped position.

Although it works, it's not really "robust". I did a "similar" thing with 4 positions and position indication using a 24 VAC synchronous motor. A roller microswitch ran on the circumference with a "notch" at each position.

The "computer" knew when the motor "was moving/stopped" and there were two hall effect sensors with appropriate magnets in a binary pattern that read out the position.

A 24 VAC geared synchronous motor is a real good way to go. I've personally used the series 49 here: https://www.hurst-motors.com/permanentmagnetacsynchronous.html

This was mot likely built with surplus parts. In this implementation, the microswitch has to handle the motor current.

So, a blank gear with a notch and a roller micro-switch would be a more robust sensor. A geared synchronous motor would be a superb drive.

But, there will be some fine line where the system will work. Pulsing the coin switch for a finite amount of time would be the way to go.

It probably does have some safety aspects to be aware of: e.g fingers, jamming
Some mechanisms can be moved by hand.

 

[Steve b]

Thanks for the reply i am currently in the procces of designing the actual housing and i will take onboard what you have suggested many thanks steve

 

[dr pepper]

I initially thought it was one of those silly machines that throws the can at you.
You could use a car wiper motor to do that, they run about that speed, and you could use something like an arduino microcontroller to control it, however with a reasonably simple machine such as that you could use limit switches and a couple of relays, a limit switch to start the motor when a coin is inserted, and another to make the motor turn 1 revolution.

 

[Steve b]

Hi,dr pepper thanks for the reply i had enitially thought about using a wiper motor because it would be cheaper than a conventional motor i will take your idea into consideration i will likely use your methos because it is more simplistic many thanks steve

 

[Les Jones]

I think many wiper motors already have the contacts fitted to make them do one revolution. If it has three wires then the option to just turn for one revolution is built in. One of the wires will need to be powered all the time and another one just pulsed to start the one revolution. The pulse from the coin detector may need extending but that could be done with an NE555. You could also just use a large capacitor and relay. A small SCR would also probably do the job. It would be latched by the coin detector and it would unlatch when the internal contacts in the motor shorted out the cathode and anode of the SCR. I think the wiper motor idea was an excellent suggestion Dr. Pepper.

Les.

 

[dr pepper]

I've used wiper motors for various things, including servo's, they make excellent ones.
I never saw a wiper motor that didnt rotate continuously, the back and forth motion is usually done mechanically, all the ones I have are worm/wheel reduction, thats what makes them good for servo's low backlash.
Most have 2 speeds and a parking switch, you need to suss this out, but thats straightforward.