Mechanical Sweets Dispenser

Hello everyone out there!

I am a student from germany who enjoys making things and I'd like to share with you the process of how I made this machine, that (as the title implies) is able to dispense sweets or in general objects up to a diameter of about 3-4cm. It's size is about 300*200*200mm.

In case you are interested in what this machine looks like in action, here's a link to a video displaying it's workings:

To give an idea of what's happening inside of the machine, this overview might help:

1.: The sweets are put into the square hole at the top

2.: A coin is pushed through the slit, lands on a special rocker and closes a circuit

3.: The now closed circuit leads lets the conveyor belt move, so that it takes a to-be-dispensed object with it

4.: The object falls onto the rocker, both it and the coin fall off of it. The circuit is now open - and the confectionery can be retrieved!

In the following I am going to show you how I built it and explain more profoundly how it works, so please enjoy!

(By the way: a "Toffifee" is a caramel-like confectionery with a hazelnut inside it ;) )

For this project is needed:

- cardboard

- skewers

- tin foil or small metal plates

- clear tape or plastic sheet

- small geared motor (with a transmission of about 50:1)

- batteries and a battery holder, as well as cables

- small weight

- Thin wood

- (small rubber bands)

- hot glue gun (or other glue)

- sharp knive

- saw for sawing wood

The ramp for the sweets, as well as the moneyslide, are made out of cardbord, wide enough so that the respective objects can glide downwards.

In order to minimise friction, so that the incline doesn't have to be too large, clear plastic tape or a plastic foil is added to the contact areas of where the tracks touch the objects.

The pictures above, in chronological order, show how the rocker, that comes into contact with both the coin and the candy, is built.

As a first step, four skewers are halved and glued together in a way the second photograph depicts. The four openings at the top are what is going to hold the rack.

Afterwards, the moving part (rocker) is built. This is accomplished by cutting out a form from cardboard that resembles a bowtie, then scoring folding lines- and folding the sides upwards. Two other distinctive shapes are cut out, too, and glued to the cardboard. Two toothpicks act as pivots.

After the whole structure is built so far, a small weight (in this case a glass marble) is added near the joint. Like so, the ends of the structure stick up.

Now the foil/small metal plates are added in a way, that when the money slides down the slide, it will land between the two contacts and close the circuit.

When a coin now lies on the right and the chocolate falls onto the left part of the rocker, both sides are tilted downwards, as it is heavier than the marble. Thus, both the coin and the treat fall down on opposite sides.

The last photo shows that the money lands in a little compartment, that can be removed.

The conveyor, as can be seen on the first picture, is adjacent to the sweets-ramp. The square hole that is part of the conveyor system sits directly on top of the rocker's left side. When the circuit is closed (see previous step), the motor turns the belt with its flaps. These push the chocolates in front of them - and into the previously mentioned hole.

The conveyor belt (picture 3) can be made by cutting a strip of cardboard, removing one face and glueing on about 4 flaps of the same material.

The two rollers are made out of relatively thick paper that has been rolled to form a cylinder. The axle is made out of skewers. In addition to that, to prevent the holes the axles are riding in to wear out, they are reinforced with superglue. Also, later on small rubber bands have been put around the rollers to prevent the belt from slipping.

The electronics of this project are, as indicated earlier, rather simple. The batteries, motor and "switch"(the two metal plates) are wired in series. It is not necessary to solder anything, but that process makes for a better bond.

The housing is made out of generic poplar wood, 4mm in thickness. Also, in all the places (except for the hole where the sweets can be reloaded,) a thin sheet of plastic is used to keep dust from entering. In the fourth picture the ramp that leads to the exit can be seen.

All of the brownish parts (like the bridge) are made with the help of a 3D-pen. It melts plastic filament, that then comes out of the nozzle and can be used to create, as the name of the product implies, 3D-objects.

Thank you very much for reading until the end, I hope you coulld enjoyed it!

If something was unclear or I have forgotten to mention anything, please do not hesitate to write a comment...!