Large cylindrical quick-connection
Large cylindrical quick-connection
(OP)
I have been asked to design a quick connection between a "part" and a rotary positioner. Currently the parts connect on a flange with 6 screws (3/8" unc)on a 11.38" diameter.
The "part" is cantelevered and weighs less than 100lbs.
The "boss" wants something like a bayonet connection or someother twist and lock idea. (like how a camera lens ataches to a camera, but this is a mighty big "lens")
Are there any standards for giant bayonet connections?
How about standards for a giant screw thread? (I am thinking maybe with 3 starts).
Has anybody seen a quick cylindrical connection around 12" in diameter?
thanks
random88
The "part" is cantelevered and weighs less than 100lbs.
The "boss" wants something like a bayonet connection or someother twist and lock idea. (like how a camera lens ataches to a camera, but this is a mighty big "lens")
Are there any standards for giant bayonet connections?
How about standards for a giant screw thread? (I am thinking maybe with 3 starts).
Has anybody seen a quick cylindrical connection around 12" in diameter?
thanks
random88





RE: Large cylindrical quick-connection
RE: Large cylindrical quick-connection
RE: Large cylindrical quick-connection
Another approach might be a multi-lead thread to make something like a quarter turn lock, Like a gallon milk carton cap (US).
A breech mechanism is a lot on machining.
http://www.clampco.com/products/flanges.asp
RE: Large cylindrical quick-connection
quick & light & stronger than the tubee
http://www.vossind.com/ makes 'em
RE: Large cylindrical quick-connection
Simplest thing to implement may be six studs, and fast-acting tooling nuts. Of course that's six loose pieces, but they're small and cheap enough to stock extras.
Next simplest thing is six ball-lock studs, which can be made captive with cables.
Or maybe some really big servo clamps.
Or just mill circumferential slots where the holes are now, so you can loosen the screws, rotate the flange and disengage it by lifting it 'over' the screw heads. The slots would have a counterbore at one end, and a through hole at the other end, both a little bigger than the screw heads.
Mike Halloran
Pembroke Pines, FL, USA
RE: Large cylindrical quick-connection
We use the Clampco and similar products with over center latches for everyday applications and don't see the problems your mention. Our application pretty much assures that the approach of the two flanges are squared as they approach.
We also have a department that uses hundreds of Tri-Clamp T-handled fittings with no problem.
RE: Large cylindrical quick-connection
The v-bands are also not designed for a lot of mate/demate cycles; the Tri-Clamps might be a better choice from that perspective.
We don't yet know the requirements for repeatability or rotational location.
Mike Halloran
Pembroke Pines, FL, USA
RE: Large cylindrical quick-connection
I have been looking and thinking about the various suggestions. all having pluses and minuses.
The vclamps are great for piping but I worry about using them for a cantelevered support.
I really like some of Mikehallorans ideas but need clarification on others.
"Simplest thing to implement may be six studs, and fast-acting tooling nuts. Of course that's six loose pieces, but they're small and cheap enough to stock extras." So simple i am wondering why i never thought of this.
"Next simplest thing is six ball-lock studs, which can be made captive with cables." I confess I do not understand this one. What are ball-lock studs?
"Or maybe some really big servo clamps." again I do not know what a servo clamp is? But if it is anything like a servo valve i think it will be overkill for our application.
"Or just mill circumferential slots where the holes are now, so you can loosen the screws, rotate the flange and disengage it by lifting it 'over' the screw heads. The slots would have a counterbore at one end, and a through hole at the other end, both a little bigger than the screw heads." I like this idea the best and will encourage the "bosses" to try it out. While a bit slower than the camera lense type attachment I have been working on, It will be much, much less expensive! Thanks Mike.
RE: Large cylindrical quick-connection
Servo clamps are visually simple cantilevered clamps that pinch the mounting flange of a servomotor. I have never seen them as big as you need, but you could have them made as custom parts for not a lot of money.
The circumferential slots are sometimes referred to as keyhole slots; I was suffering a little brain fade and couldn't bring up the term.
Mike Halloran
Pembroke Pines, FL, USA
RE: Large cylindrical quick-connection
RE: Large cylindrical quick-connection
why do you not recommend the bayonet system?
RE: Large cylindrical quick-connection
Check out the tooling component companies like Carr-Lane, etc., for ideas of how to do quick-mount fixturing.
Something along the lines of EdDanzer's comment, look at using a robotic end effector quick change device from www.ati-ia.com or similar companies. That would give you a quick easy solution, but you'd have to have pneumatic power on the unit.
TygerDawg
RE: Large cylindrical quick-connection
RE: Large cylindrical quick-connection
I had expected the small clearance that is why i figured it would be very expensive to manufacture to small tolerances. I had not considered contamination. Now i have yet another support for the keyhole method. I got support from some of the "bosses" for the keyhole method yesterday. I am also thinking that since we don't need all 6 bolts we don't need 6 keyholes, that will speed up the equipment changing.
TygerDawg
pneumatics is not an option. thanks for the ideas anyway.