Quick release mechanism

[RobertCasey]

Hello. Does anyone know of a company that manufactures quick release mechanisms that can be incorporated into other devices? It would need to be able to hold loads up to 10kN, before releasing them on a given signal. The mechanism will be required to operate every 40 seconds over an operating day of 5-6 hours so wear is probably going to be an issue. I have looked at using an electromagnet, but I was wondering if anyone makes a mechanical equivalent. Thanks!

 

[FeX32]

Sorry, can't help you there. Have you thought about building your own?

Fe

 

[KENAT]

If nothing else, look into how bomb racks on aircraft do it. Marvin is one manufacturer as I recall.

KENAT,

Have you reminded yourself of faq731-376 recently, or taken a look at posting policies:

http://eng-tips.com/market.cfm?

 

[unclesyd]

That a look at the Sea Catch. Work like a champ. There are quite a few variations on the theme.

http://www.seacatch.com/

 

[FeX32]

Are you going to electronically control the mechanism?

Fe

 

[zeusfaber]

I suspect the difficult bit will be achieving the reset required to make it possible to work every forty seconds.

Most of the mechanisms I've seen (slips, Capewells and three-ring-circuses, for instance) involve levers held in place by other levers, and need a fair amount of assembly after every release.

A

 

[FeX32]

I agree with the above. That is why I thought an option might be to construct your own that can be particular to your case. Could even be something as simple as a slotted 4-bar mechanism controlled by a DC motor.

Fe

 

[budt]

Perhaps this 527 Page book, that you can download here, can give you some ideas.

http://www.scribd.com/doc/8964585/Mechanisms-and-Mechanical-Devices-Source-Book-

Bud Trinkel, Fluid Power Consultant
HYDRA-PNEU CONSULTING

 

[dvd]

It might be appropriate to know what exactly you need to hold for quick release. What sort of shape is it? Are you really moving 10 kN (~2250 lb) every 40 seconds? I would have some concern about accel/decel loading at that quick rate. I don't think you're going to get any very specific suggestions unless you describe the process better.

 

[IFRs]

You may to look at clamps for press brake dies. High clampoing forces, electric, hydraulic, pneumatic. For instance

http://www.destaco.com/img/prod/7011-5.jpg

 

[tygerdawg]

Ditto IRFs comment. Tooling components suppliers like DeStaCo, Carr-Lane, and Jergens typically have pneumatic / hydraulic clamp devices. There are designs similar in function to the SEACATCH device given above, but also cylinder designs that provide an up-rotate-down motion for automatically clamping tooling plates.

TygerDawg
Blue Technik LLC
Virtuoso Robotics Engineering

http://www.bluetechnik.com

 

[rb1957]

you're releasing 1ton every 40 sec for 6 hours ... that's a lot of tons ... (6*60*1.5 = 540 tons !) ??

how big is this "thing" ?

is it something that drifts away, or falls away (under gravity (ie the clamp is also restraining the weight) ?

how are you "re-loading" it (in < 40sec) ?

 

[btrueblood]

http://www.mcmaster.com,

p/n 3398T31 (probably the same thing that unclesyd gave, but a different source).

But...as others have said...dunno how you would reload and release in 40 sec.

 

[RobertCasey]

Thanks for all your replies! The device is a brake on a amusement ride. The brake is a non-contact magnetic brake which consists of a 1.5m long reaction plate which is brought close to the vehicle mounted magnet. The reaction plate is held up to the vehicle using springs (required so that the plate always moves up in case of power loss),and moves vertically down 110mm when the brake "releases". The brakes are used to control the speed of the vehicle and so need to be able to move rapidly (ie the 110mm stroke in <0.2s). The magnets exert a very strong attractive force on the reaction plate and its that force I have to overcome. The force does drop off rapidly as the plate gets further away, and so I was going to use a series of fluidic muscles to pull the plate down because their pulling force also drops as the muscle contracts. The problem that I have, is getting the appropriate volume of air into the muscles in such a short time frame, and so I was intending to lock the reaction plate, pressurise the muscles and then when the plate was needed to move, release the mechanism. The actual moving mass is quite low (ie 15-20kg). I can find electromagents which are suitable but they are heavy (approx 40kg) so thats why I wanted to see if there was anything more mechanical and lighter! Thanks for your comments so far!

 

[btrueblood]

...at the same time, the mechanism for these

http://en.wikipedia.org/wiki/File:Fort_Casey_Disappearing_gun.jpg

could IRRC cycle as fast as 60 seconds with a trained crew of 8-12 men; most of the delay was due to swabbing the barrel, and reloading shell and powder.

 

[FeX32]

Interesting.....

Fe