I drive a Chevy Suburban that has a large plastic surround for the ceiling light. The company installed the punch/cutter on that plastic surround, cementing the holder in place. From that position, anyone in the front two rows of seats could reach it. If it was still there.

Sue

Sod, if you look at the youtube vid I posted on the other seat beat cutter link (not sure which, there are 3 going around now), it shows that it takes a bit of a tug to seperate the cover from the cutter. Unless you have weight on the cover, it looks like it should be ok.

I would interested in finding out how the seat belt cutters work on the new inflatable seat belts designed by Ford. I believe they are going to be installed on the Explorer first next year and eventually adapted to all their vehicles in the future.

http://www.independent.co.uk/life-style/...ts-1816548.html

I wonder if using the seat belt cutter would initiate an automatic attempt to inflate the seat belt bag? Secondly, would it snag on the belt that would be a combination of fabric and nylon webbing. These are REAR seat belts only because the front occupants already have airbags.

1. Seatbelts
2. Children
3. Window
4. Out

Is the entire belt going to be inflated? I would think that it could not be at the portion where the belt passed through the buckle. If I still had my wits I would attempt to cut nearest that portion (which would also be less to pull through).

Perhaps someone can clear this up for me, but WHY in the world is seatbelt jamming such a common problem?

You'd think they could design a buckle that would still function after an accident.

I think it's just inherent in the mechanism. On my Jeep's factory seatbelts, if I get the Jeep leaned over far enough the belts are extremely hard to get off. Plus it might have your full weight on it also. And then they are impossible to put back on due to the fact that they retract and won't come back out.

This is why I'm buying and installing racing harnesses in my Jeep for offroading. They are non-retractable and a heck of a lot beefier, plus they are specifically designed to be easily unlatched after an accident.

I'll just guess, but I'd say it's because the top two things, besides cost, they're looking for is: 1) that it doesn't unbuckle under any survivable load and 2) that when it goes "click" it's always locked. Obviously a latch that released on impact would be bad, and a false lock would be bad, too. So they're probably designed to latch harder as they're loaded.

I would bet that the design of airplane seatbelts is different, that they're designed to always be easy to release, at the expense of not being as certain to lock, because the risks are different.

Or it could just be dumb luck and bad engineering...

I am sure that the seatbelt jamming problem can be made smaller with a tiny amount of lubricant. They probably could do with a bit of lubing anyway. Don't use too much as excess oil will stain the clothes or seats. And don't expect it to eliminate the jamming problem.


With such heavy loads, I would expect the stress bearing parts of the locking mechanism to carve grooves and scars into each other, creating an interlocking set of grooves. They may also be bent microscopically out of shape (not anywhere near the point of breaking). Anyway, "keep it greasy and it'll slide easy". Anything stuck with lube present would be 10 times more stuck without lube...


Caveat: I don't know if manufacturers has put in any long lasting grease in the seat belt locking mechanism, such as grafitti (used in locks, btw). If there is, say, grafitti present, adding new oil will create a mess (oil flushing out the grafitti). And from that point you need to oil / grease regulary.

They do not "jam". There used to be a serious problem with seat belts coming undone in a crash. After a lot of research was done (mostly in the U.K. by the Department of Transport) the modern seat belt was designed. It is designed in such fashion as to ensure that if the lock fails the parts jam closed.

It should be appreciated that in 99% of all crashes the safest place for the driver or passengers is in their seats.

Situations like the present tragedy are the exception, not the rule.

Naturally we'd like the buckle to fail jammed rather than fail open, but why must it be a binary solution set?

How about option 3: Doesn't fail or jam under a survivable crash loading.

To unlatch while under a load may be asking too much for an automotive style pushbutton release, but the "aircraft style" ought to provide more leverage.

Honestly, current automotive safety systems are so much Mickey Mouse. Race cars don't have airbags or belt tensioners. They have a real harness with a real latch. Yes, I know that's "more expensive" but then again, how much do air bags cost these days?