Shopping cart unlock key

thingiverse

This device can be used to unlock shopping carts when you do not have a coin (nowadays where no cash is needed) or when you do not want to grab your wallet when having no free hands. I tested this version on some carts in Switzerland and it worked for all locks so far. Due to its design, it should work for all locks that allow removing an object that is about 5mm smaller that the normally blocked coin. When the inner part is pushed to the tip, the resulting shape is exactly circular with the size of the coin. When retracting it, the width of the 'coin' shrinks and it can be removed, no turning required. I suggest printing with some more flexible material like PETG or Nylon. Use a layer height that is a odd fraction of the coin thickness (15 layers of 0.143mm for CHF2, 0.147mm for EUR2) for best symmetry. If other coin sizes than CHF2 or EUR2 are required, change the User-Parameters in Fusion 360 as required.