As you can read in the first article about the Ticket Dispenser Unit (click here for the article), the version for Lego World 2016 a ‘fast build’. Nevertheless, it worked almost flawless. Almost … sometimes the card was not transported to the end. With just some small modifications, it works even better now.
The TDU consists of two parts, the reader part (see the earlier mention article about this) and the dispenser part. The dispensor part works rather simple: the stack of tickets is placed in an angle, gravity ensures that only one ticket is dispensed at the time. The wheels on top of the stack rotate a small amount of time, just enough to get one card fall on the conveyor belt. Due to friction, the ticket directly under the top one is also moved a little, therefore I reverse the motor for a small time afterwards.
The conveyor belt consist of wheels (42610) that do not have a cross in the middle.
Due to the friction with the axle, they rotate just enough to transport the ticket over the conveyor belt. However, at Lego World we noticed that the ticket sometimes gets stuck under the sensors. So I added two larger wheels on top of the belt to help the ticket to get to the end of the conveyor belt.
Pictures of the TDU version 2017 can be found at our Flickr page: https://flic.kr/s/aHskHKJoy1.
And a video of the TDU version 2017 at our Youtube channel: