Impossible objects #9: Door lock chain maze

It is described as an ingenious “thief-proof home door lock and chain maze”, but I’m not so sure.

It’s not so much that it is hard to let someone in, more that you can’t get out. A Kafka-esque entrance exit conflict.

It is made from Titanium Alloy and fixed in place with 10 different screws, apparently, and load-tested against 700 pounds of force…

Thanks to Gizmodiva for this one, referencing another high-design concept from Art.Lebedev, which calls it the “Defendius door chain“

Previous Impossible Objects we’ve covered:

• the dark lamp

• the global chess board

• the curved keyboard

• the implausible plug
• the infinite tap
• the simplified calculator
• the electric hammer
• the signature coffee pot

7 Comments

1. 
   AlanB
   June 12, 2009

   With a chain that long, anyone who couldn’t generate the necessary 700 pounds of force could probably just squeeze through the gap!

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2. 
   Alun Williams
   June 12, 2009

   It’s strange this one, Alan. At first glance it’s amusing, but the more you think about it the more wrong it is.

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3. 
   charles peirce
   June 17, 2009

   I don’t care how strong it is, the other end of the chain is still only held by two screws in the door frame.
   I bet less than 70 pounds force will open that door!

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4. 
   Alan
   June 17, 2009

   Hummmm well I think the reviewer doesnt use a guard chain. The idea is that it is NOT put on when you are in the house with the door locked. Then when someone calls you engage the chain before opening the door sufficient to converse with them. The plate should be mouned in a position where it can only be engaged with the door shut. I dont see that this is any extra protection to a decent lock system and a normal chain properly installed…..another example of Newspaper advert hype sales…..but certainly a “talking point” for friends.

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5. 
   Alun Williams
   June 18, 2009

   You may have a point, Alan. Maybe it says something about me, but first thing I do when i get back home, and shut the door, is put the chain on…

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6. 
   jay
   July 01, 2009

   Great accessory when the building
   catches fire…..
   j

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7. 
   jay
   July 01, 2009

   Great accessory when the building
   catches fire…..
   j

   reply