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Load Arrestors for Falling Masses
2

Load Arrestors for Falling Masses

Load Arrestors for Falling Masses

(OP)
I need a device to arrest or catch a falling load of approximately 2000 lbs (similar to a fall arrestor for personnel safety). It should use an interia activated brake or catch mechanism like those found in automotive safety belt restraints. Does anyone know of such an animal?

RE: Load Arrestors for Falling Masses

If you have had any luck finding such a device I would really be interested. I currently have an application where I could use it.

RE: Load Arrestors for Falling Masses

(OP)
From my research, I found only one company making such a device. I need a very fast response time for my application because I have to catch the falling mass within a span of only a couple of inches. I don't believe this device will work for me.

You can check it out at:
http://www.norguard.com/site/products/nor_3700300.html

Hope this is useful information.

RE: Load Arrestors for Falling Masses

I am a manufacturer of Linear Brakes that have a force capacity of up to 5500 Lbs., however it is a spring set/air release actuation so it may be more involved than what you are looking for as with the inertia activated system.  Primarily used for machinery rather than a free hanging load so depending on your application...

RE: Load Arrestors for Falling Masses

(OP)
Brakes,
I am trying to catch a large rotating assembly in the event that the actuating hydraulic cylinder suffers a catastrophic failure allowing the mass to rotate with full force from the vertical to the horizontal position (90 degrees). The inertial activated brake sounded like a good idea because of its simplicity, unfortunately the response time is not very good. Since this is a safety device, it must be able to stop the falling mass in a hurry.

I am not sure how a linear brake would work in this arrangement but would like get some information on your device just in case.

Thanks

RE: Load Arrestors for Falling Masses

wxashcra,
We manufacture drum brakes and the linear brake can also operate on a disk (or partial disk for 90 degrees operation), so depending on your system's mech. design, inertia, stop time, etc., we may have a solution that could work for you.  You would however, have to incorporate a way to sense a failure and have the control system respond (dump pressure to brake).  The brakes have a quick response time (~65 msec.)and are failsafe in their operation so they are optimal for safety applications.  Please visit our website: www.holeindustries.com for more info and feel free to contact us if you would like to discuss further.

Thanks

RE: Load Arrestors for Falling Masses

wxashcra,
We manufacture seatbelts and use many acceleration sensative retractors.  The important thing to determine if you are using a seat belt retractor is the acceleration rate at whih the internal mechanism will lock up.  Most seat belt retractors that are mono-sensative (or sensative to acceleration of webbing despooling) are Federal Motor Vehicle Safety Standard (FMVSS) 209 compliant which regulates the sensativity and lock-up window of such retractors. This acceleration is regulated to be 0.7 g and the lock up window (the distance to be unspooled before lock-up) is also regulated.  This entire standard is availible on the NHTSA website for free.  Also, any seat belt retractor that is mono-sensative and certified to comply with FMVSS 209 will probably work in your application,  they have a a 2500 lbf. minimum tensile strength requirement.
If you find FMVSS 209, look at requirements for an Emergeny Locking Retractor, mono-sensative.  I hope this helps.  If you care to contact me for more info, pleas feel free.

Rnel

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