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View Full Version : Seatbelt retractor orientation...why does it matter?



chevynut
05-03-2014, 08:17 PM
From all my research into retractable 3-point seat belts, it looks like they all basically come from one manufacturer and are sold by lots of dealers. Virtually all of them use "web sensitive" locking retractors.

I bought a set of Juliano's 3-point seat belts, but it turns out I don't like the color. So I have been looking at other dealers to get the color and features I want.

I ran across this warning from one dealer who says:

http://www.seatbeltsplus.com/product/WSCH201P.html
Proper Installation Requires:
-Retractor must mount upright/vertically (90 degree angle from floor).

Retractor MUST mount in a upright position.
Our Seat Belt Retracting Mechanism MUST mount vertically. A tilting retractor will not function properly and can result in serious injury or death. Retractor must mount either on floor (mount upright with"L" Bracket) or can be mounted on door pillar if mount already exist. Do not mount retractor on ceiling, body quarter panels, inside seats, attached behind seat, or feeding through seats.



Most of the seat belt retractors I've seen are the inertial locking (web sensitive) design, that locks when the belt is pulled quickly. This website describes how they work:

http://auto.howstuffworks.com/car-driving-safety/safety-regulatory-devices/seatbelt3.htm

Here's an article showing a Mustang convertible installation on Juliano's site. They didn't mount the retractor vertically, and DID mount it behind the seat.

http://www.seatbeltstore.com/Articles.asp?ID=246

http://www.seatbeltstore.com/v/howtoimages/mustang-seat-belt-install-075_small.jpg

However, in this article they say:

http://www.julianos.com/how2_3point_antique_chevy_truck.html

"This placement meets the strict requirement that the top shoulder post be directly above the retractor while keeping the belt assembly out of the way. "

So why does it matter where or what orientation the retractor is mounted in? Juliano's retractors look exactly like the others I've seen on numerous seat belt dealer websites. I think it looks like the centrifugal clutch would work whether the retractor is mounted vertically, horizontally, or at an angle. I can understand why an inertial-locking retractor needs a particular orientation, but not a web-sensitive one.

Rick_L
05-03-2014, 08:31 PM
I always thought the orientations were for routing of the belts, and their relationship to your body (i.e., twisting/side loading of the belt, submarining of your shoulder, etc.). I can understand recommending that the belt should be routed so that it always pulls straight out of the retractor. Never heard of the retractors having restrictions. After all they are inertia devices, not gravity devices, aren't they?

I interpret Julianos' recommendation to be for belt routing, not the retractor. And maybe Julianos' retractor is different.

And come to think of it, the lap belt only retractors mount at an angle (like from a 60s car). Every one I've ever seen.

chevynut
05-04-2014, 06:54 AM
That's what I alway thought too, Rick. I took my retractor and tried it in every orientation and it works the same no matter if it's upside-down or whatever. Maybe this is some left-over urban legend/wives tale from the days when inertial-locking retractors were more prevalent.

The reason I was interested is that I plan to mount my retractor about 20-30 degrees from vertical. The webbing will come straight out of the retractor as its supposed to.

Rick_L
05-04-2014, 09:12 AM
Maybe the seat belt vendor was the one that didn't understand. I think all you need is to provide belt routing so that it pulls straight out of the retractor.