Quick Disconnect Shaft Coupling 2

[ERIMechEng]

Problem: Need to drop load-bearing shaft into a mechanism, and couple the load bearing shaft to a shaft with a brake (please see linked PDF). Zero torque, zero speed until shafts are coupled. Shafts are both approx. 1.5" dia. Transmitted torque = 600 in-lbs @ 100 rpm.

I need help with the coupling mechanism. Must be manually operated - no elec, hyd, or pneumatics available. Also, need something maintenance free (or very low maintenance). I would prefer something off-the-shelf.

I have found something that will probably do the job:

http://www.daytonsuperiorproducts.com/couplings/disengageable-couplings.html

but I was looking for any alternatives. Any ideas?

/R - Matt

 

[NomLaser]

When you say zero torque zero speed until coupled, do you mean that neither are not rotating prior to coupling?

Here is a company that I have used in the past with good success. This style is usually pretty inexpensive and the rubber inset life will vary with the amount of misalignment that you have in the setup.

http://www.hayescouplings.com/index.php/products/lseries_jaw_couplings

 

[ERIMechEng]

NomLaser -
Correct: Neither the loaded nor the brake shaft will be moving until both are coupled together.

I've seen some of those spider coupling devices, but the problem with those is that the device can't be coupled unless there is some axial movement of one of the two shafts.

What I need to be able to do is bring the loaded shaft down and bring it parallel with the brake shaft. Then I need to couple to the brake shaft - the shafts cannot move in the axial direction.

Also - and maybe I should have said this before - I would prefer a device that has no "loseable" parts. What I mean is I have to try to minimize the number of small parts that can be misplaced.

 

[NomLaser]

Those do have a through bore with a set screw. So if you have enough room on your shaft you could slide it back when installing then move it forward when you couple them. You would need to key both shafts though.

 

[ERIMechEng]

Keying the shafts is no big deal. But I still run into the problem of a) the spider or inset can be misplaced, b) I have zero axial movement available on the shafts.

I'm not trying to be difficult, NomLaser, and I really appreciate the suggestions.

 

[israelkk]

How about a friction disk clutch, the disk is pressed aginst spring/s at rest. When the handle shifts the spring allowed to push the friction disk aginst the mating disk on the second shaft.

 

[ERIMechEng]

@ israelkk
That might work, but all of the friction disk clutches I've seen have a housing that surrounds both the friction and mating disks, This means that I can't "drop in" the loaded shaft.

 

[NomLaser]

Search for grid coupling. Used to use these on dyno's in the past. Basically it's a splined hub that you place on each shaft. Then there is a spring that fits in each tooth. Then you bolt on a guard around the assembly. They work pretty good and we never had issues on our dyno's.

http://www.machinerylubrication.com/Backup/200211/LubApp-Fig4.jpg

http://img.directindustry.com/images_di/photo-g/flexible-coupling-grid-coupling-358875.jpg

http://img.directindustry.com/images_di/photo-g/flexible-coupling-grid-coupling-221874.jpg

 

[diskullman]

Rexnord Omega couplings are maintenance free

http://pt.rexnord.com/customer_support/technical_information/4041.asp

Russell Giuliano

 

[BobM3]

Magnetic disk style clutch? Rimtec makes some but not quite big enough for your needs. The axial gap has to be controlled - possibly with a thin aluminum (non magnetic) plate.

 

[ERIMechEng]

@BobM3
Nice suggestion, though I'm a little concerned about the fragility of exposed magnets in this setting.

Thank you to all who have responded. I'm going to have to come up with a design solution by the end of the week, so (if ya'll care) I'll be posting the resolution next week.

 

[Compositepro]

Your application sounds similar to core shaft chuck. Machines that process rolls of paper or similar material which is supplied on cores, support the rolls on shafts through the core. The loaded shafts then have to be lifted and dropped down into coupling chucks that fit the square ends on the round shafts. The chucks are attached to brakes or drive motors.

Old style chucks had a simple sleeve that would slide axially to open one side of the female square and slide back to trap the male square. These, however, could be open in the upside-down position allowing the shaft to drop out. Safety chucks can only be opened in one position and will self close when the shaft rotates. The key search term is "safety chuck".

 

[ERIMechEng]

YES! Composite pro, that's exactly what I'm looking for. I'm surfing around trying to find one of the "old style" ones you are referring to. If you manage to find one that can be mounted to a 1.5" shaft, please let me know. That square configuration sounds perfect.

 

[unclesyd]

compositepro is correct in stating that roll will come flying out of a machine as I was nearly hit by 2500# roll of nonwoven fabric.

Here are two chucks that I'm familiar with, the Super Chuck and the Nexen.
I'm partial to Super Chuck as I got a $1500 suggestion award for replacing the existing very unsafe ones.

http://www.super-chuck.com/

http://www.nexengroup.com/sc/

 

[Compositepro]

You will probably have to make your own to meet all of your design requirements, but here is another concept that may be useful:

http://www.converteraccessory.com/products/shaft_support/skew.html

 

[ERIMechEng]

I think I'm going to go with the Medium duty flange mount displayed here:

http://www.converteraccessory.com/products/shaft_support/ss214.html

Exellent recommendation. Now I've gotta figure out how I'm going to clamp the square shaft to the spool. Incidentally, it's a 2 foot dia cable spool, full weight 900 lbs. 18" wide. Center of the spool has a steel-lined 1-17/32" dia center core.

 

[NomLaser]

I wouldn't mind seeing a simplified drawing of your setup once you get it designed.