Born out of the frustration of adding yet another pair to the dozen pair of children's glasses, all broken the same irreparable way: The Slip spring connector.
A spring hinge is the hinge on a pair of glasses frames that connects the part that holds the lenses to the part that holds your ears and allows it to fold.
The spring hinge may also cause the frames to have a sort of shape memory so that you don't have to constantly adjust the hinges to realign them for someone who is rough on glasses - to be honest, it may also be made to cause the parents of kids to have to buy more glasses when they get broken, I don't know.
The problem I have with it, is that the spring hinge has the springs inside the frame of the glasses attached to a thin piece of metal THAT BREAKS and, once broken, slides back into the frame, rendering repair expensive, or impossible. You can't even switch out parts as both the connecting pieces are ruined.
The Slip spring connector changes the thin piece of metal into two pieces of metal connected by a spring type rotating hub on the top and bottom clasping on to a stationary hub sandwiched in between.
If a force is applied in the direction that would normally break the regular spring hing, the rotating hub has an interior track that is formed in alignment with the stationary hub which will force the clasping part of the rotating hub apart to eventual separation WITHOUT damage to any part.
I am actually having a hard time describing how this works. I think there are connections that already exist like this, but I am drawing a blank on what they are right now.
They work in a manner similar to what I wrote, if two pieces are connected in parallel, the connection is strong, but if the two pieces start to form an angle, the connector widens and eventually releases the connection between the two pieces.-- Zimmy, Jan 23 2009 Best Solution I've seen http://images.googl...l%26sa%3DN%26um%3D1unbreakable. [loonquawl, Mar 23 2009] My current pair of glasses simply has a very springy metal for the ear pieces. Any required flexing is handled there rather than at the joint.-- MechE, Jan 23 2009 random, halfbakery