Tamper Resistant Lock Concept

[Dragunov-21]

Ok, I know I’m a newbie who’s probably overlooked something crucial, but I’ve had an idea for a tamper-resistant lock for places where it’s very preferable to sacrifice a lock than allow entry to a place.

Basically, the pins are made of glass, with the driver pin being a serrated, spool or mushroom pin, and the key pin a mushroom or spool. When the correct key is inserted and turned, great, but when a pin binds through the application of torsional force, it snaps, bits of glass gum up the lock, and once the pick/foreign object/etc is removed, a metal rod contained in the spring drops down, preventing someone from just using a screwdriver to bust the pins and open it. Of course, once this happens the lock is ruined and needs to be drilled, but there you are.

I’m hoping the diagram will explain things better, any feedback would be great.


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[UWSDWF]

i came up with a similar idea some time back andothers concluded that if the glass were to break that easily in tampering situations then in normal use conditions could end up doing the same

[Dragunov-21]

I did wonder about that, but if the glass were hardened/tempered (correct term?) then it would have high strength from top to bottom (and thus resist wear and tear, but still be brittle enough to break under the force of being scissored between cylinder and hull?

Or perhaps I'm talking out by butt

[freakparade3]

So if you are inside your home and someone breaks the glass in your lock you are just stuck until a locksmith drills you out? I know houses have 2 doors but lots of condos and appartments do not.

[Dragunov-21]

I was thinking more for things like storage rooms with... dangerous stuff... behind them. Ok, that was pretty half-baked, but if there was a situation like that then it'd be easy enough to put a bypass on the back pf the door...

Like I said, I've overlooked stuff, but I still think it'd be interesting to try academically...

[Schuyler]

This isn't designed to be used on a house. It's a seal lock, meant to detect surreptitious entry and to lock safe in the case of any major trauma to the lock.

There is a market for this sort of thing.

[Dragunov-21]

Exactly, for instance, if you were a highschool principal, overseeing a science department with a storeroom full of acids, explosive reagents etc, would you rather call a locksmith to drill and replace a lock the next morning, or explain to horrified parents that it's not your fault that their kid-cum-chemist has nicked reagents and put himself in hospital?

Of course, if it was an environment like a school where the lock was likely to be regularly messed with, you'd want to put a padlocked sheath over the door lock so you weren't constantly having to replace expensive locks, and for a highschool something like an Abloy would probably be sufficient anyway, but you get the point.

[Trip Doctor]

That's what trap pins are for isn't it ?

Once this design would be discovered, someone could easily use a pick or a tension wrench to keep 'rods' from dropping, and the cylinder would then be forced open with a screwdriver (snapping all the pins). On the other hand, entry WOULD be detected, just not prevented.

I think trap pins are the solution to this.

[Trip Doctor]

Actually, now that I relook the trap pin design those can be bypassed/picked pretty easily too.

[Dragunov-21]

Well the idea is to not have the lock readily identifiable as having said pins, so that by the time the picker realises, it's too late. You could even put neobdynium? magnets at the bottom pits to stop the rods being raised again.

[mh]

I did wonder about that, but if the glass were hardened/tempered (correct term?) then it would have high strength from top to bottom (and thus resist wear and tear, but still be brittle enough to break under the force of being scissored between cylinder and hull?

Or perhaps I'm talking out by butt

You would have to consider that
inserting the key
also applies a shearing force on the pins.

Keep bringing up your ideas!

Cheers,
mh

[n2oah]

Actually, now that I relook the trap pin design those can be bypassed/picked pretty easily too.

It depends. TOOOL once tested a lock with trap pins(does anybody remember the name of it), and they could never pick/bump the lock, even when trying to keep the trap pins in place when rotating, or trying to force the trap pins back up.

[mh]

Actually, now that I relook the trap pin design those can be bypassed/picked pretty easily too.

It depends. TOOOL once tested a lock with trap pins(does anybody remember the name of it), and they could never pick/bump the lock, even when trying to keep the trap pins in place when rotating, or trying to force the trap pins back up.

And I never understood why they could not.

Actually I find some of the statements in that area quite strange - if some people find a weakness in a lock, they state correctly that it's not so secure.
But if they can't overcome an obstacle, they also make a statement to the effect that it's very secure - although that is so much more difficult to prove and the next guy trying could be more lucky or creative...

[bluestar]

Well, let's look at the acid container room example.
case a) using a wrong key. It lifts the pins too much and breaks them, but opens the lock.
a1) you can open this lock with the wrong key or, in an extreme case, just by using a blank. It's locked afterwards, but who cares
a2) you could easily lock this lock forever by simly pulling out the wrong key (which i imagine could happen quite a lot)
b) Someone steals the key. Bad luck. Use an additional combination lock.
c) One can pick the lock, but the lock locks itself -> just remove the glass stuff and lift the top pins with a very long hook -> voila

Just some thoughts...
blustar

[greyman]

Nice post, from Tasmania, to boot My ancestral roots lie there - in the Tin mines of the north...

Interesting idea - I haven't seen glass proposed as a trap mechanism, and there may be a good reason for that. There are many trap mechanisms for pin tumbler and other locks - but the real problem as you have encountered is the need to dismantle the lock if it's been triggered. That is why more than 150 years ago Chubb developed the detector lever mechanism. This could be reset using a separate key hence no need to dismantle anything. Tobias's book has a few examples of patents where there are trap pins, etc. In fact the MLA Binary Plus mechanism has trp pins that are reset by the correct key.