Master Lock Applies For Patent On Bump Proof Pins

[jimb]

In the July issue of The National Locksmith there is an article on Master Locks Development of bump proof pins. It's a good read, if you don't have it try to borrow a copy.

I want to start by saying that a while back someone here took a rough ride for a comment they made regarding how a lock reacts when bumped. According to Master Lock this person was correct. Master Lock did some high speed video of locks being bumped, 2162 frames per second. The result was that the pins separate on the way down and not on the way up as has always been believed.

The article describes several different methods and modifications they tried before coming up with a solution that they claim is 99.99% bump proof. It is just a different pin design that they say only needs to be added to one chamber to work. It also will leave telltale signs if bumping is attempted. This modification is suppose to be available in all Master Looks by Oct 07.

[dougfarre]

Can we read the article. That is really interesting!

[greyman]

That is interesting. I still find it difficult to believe that the pins separate on the way down. That seems to be against the laws of physics. My understanding is that the lower pin transfers the energy to the upper pin, like in Newton's cradle (the row of balls on strings). The upper pin moves up because it can - it has sufficient energy to compress the spring.

For the pins to separate on the way down, there would have to be unequal forces on them, actually slightly more force on the lower pin. Where is that extra force coming from?

Can you quote the passage that covers this bit from the article (without breaching copyright)?

[jimb]

Can you quote the passage that covers this bit from the article (without breaching copyright)?

They explained this with 3 drawings and 3 lines of type as well as a some what large paragraph. For fear of infringing on the copyright I'm just going to quote the 3 lines of type under the drawings. The paragraph is pretty much the same.

Line 1 reads: The bump key impacts the bottom pin.
Line 2: Key pushes the entire pin stack violently upward.
Line 3: The bottom pin descends and separates from the top pin.

[jimb]

I just want to add that they did not offer an explanation on why this happens.

I have a theory that the spring tension keeps the pins from separating while they are on there violent way up. At least enough for both pins to pass the shear line. at some point past the shear line the bottom pins drop. This would only take a split second for the bottom pins to drop back down. While the bottom pins make their journey down the top spring and pin are still moving upward.

[greyman]

[...]
Line 1 reads: The bump key impacts the bottom pin.
Line 2: Key pushes the entire pin stack violently upward.
Line 3: The bottom pin descends and separates from the top pin.

Thanks for posting a summary. I'm just trying to make sense of this. Maybe the bottom pin isn't just "separating from the top pin", but rather it is moving updard with slightly less energy than the top pin, having tranferred a fair bit of the impact to the top pin. This would mean that the bottom pin would move up less than the top pin, therefore it would return under its own weight sooner because the top pin, as you say, is still moving upwards. Just goes to show how complicated the dynamics of bump keys really is. Fascinating

[Trip Doctor]

[...]
Line 1 reads: The bump key impacts the bottom pin.
Line 2: Key pushes the entire pin stack violently upward.
Line 3: The bottom pin descends and separates from the top pin.

Thanks for posting a summary. I'm just trying to make sense of this. Maybe the bottom pin isn't just "separating from the top pin", but rather it is moving updard with slightly less energy than the top pin, having tranferred a fair bit of the impact to the top pin. This would mean that the bottom pin would move up less than the top pin, therefore it would return under its own weight sooner because the top pin, as you say, is still moving upwards. Just goes to show how complicated the dynamics of bump keys really is. Fascinating

If that, then this is the same theory as though before is it not? But rather than the bottom pins transfering all the energy to the upper pins.. they just transfer most of it, and because of this they fly up a little as well, seperating on the way down instead of up. If you have 2 balls on the pendulum thing, and you throw one really really fast.. I think you will eventually get it to move as well, though not as much as the one it's hitting...but.. I'm not a physist.. so.. I shalln't say too much since I don't know that much.

[jimb]

If you have 2 balls on the pendulum thing, and you throw one really really fast.. I think you will eventually get it to move as well, though not as much as the one it's hitting...but.. I'm not a physist.. so.. I shalln't say too much since I don't know that much.

But what if you put a spring on the other side of the second ball.

If no spring was involved then the pins would separate on the way up. I think the spring is the key. No pun intended

[Schuyler]

already posted here:
link-o

with links to scans of the article.

[n2oah]

Here's my explanation of Master's "pins seperate on the way down" theory:

Crackpipe
+

Science
+

+
Phencyclidine
= bump proof master lock

[Eyes_Only]

For a second there I was expecting to see UWSDWF's sig at the very end.

[globallockytoo]

I'm posting a link here to another thread where I uploaded three pages of the article in Keynotes magazine that explains the principle in detail.

viewtopic.php?t=18741&postdays=0&postorder=asc&start=90

[Schuyler]

I'm posting a link here to another thread where I uploaded three pages of the article in Keynotes magazine that explains the principle in detail.

I just did that, 2 posts ago

[jimb]

I'm posting a link here to another thread where I uploaded three pages of the article in Keynotes magazine that explains the principle in detail.

viewtopic.php?t=18741&postdays=0&postorder=asc&start=90

This is the same article that appeared in The National Locksmith, except for some verbiage under some of the drawings.

Does this article not carry a copywrite in Keynotes?

[greyman]

globallockytoo - the article (and thanks for making it available, despite copyright issues, etc) does say that the separation between the pins happens on the way down, but it does not seem to explain why it happens like that. There is something funny going on here, and at first read it definitely smacks of pseudo-science. N2oah - I did like your lucid post on this

Maybe there's some odd effects going on here. Another example where you get unintuitive behaviour is snooker balls - the static charge the balls pick up from rolling across the felt on the table makes them tend to stick together during collisions. Maybe there's something about brass-on-brass that causes the collision to be less than "ideal". All the same, I cannot see why the lower pin would fall back sooner than the top one, which has the force of the spring on it also.