Torque Limiting Clutches
Torque Limiting Clutches
(OP)
Hey guys,
I have a DC motor that I will most likely chain drive a shaft with. The output shaft will need to be limited to 27-37 in-lb. The output shaft will rotate very slowly. (no specifics yet, but probably at least under 50RPM).
I need to find a cheap torque limiting clutch that in one direction will limit my torque to 27-37 in-lb, and in the opposite direction, not limit my torque at all. Also another option is having my torque limits set to different values for each rotational direction.
Is there a specific name for these types of clutches that allow for limitation in one direction, but no limitations or alternative limits in the opposite?
Size is not an issue at all for me, I just need something cheap. Limiter can be implemented on the sprocket, input shaft, or output shaft.
Does anyone have any suggestions to get me started in the right direction?
Thanks!
I have a DC motor that I will most likely chain drive a shaft with. The output shaft will need to be limited to 27-37 in-lb. The output shaft will rotate very slowly. (no specifics yet, but probably at least under 50RPM).
I need to find a cheap torque limiting clutch that in one direction will limit my torque to 27-37 in-lb, and in the opposite direction, not limit my torque at all. Also another option is having my torque limits set to different values for each rotational direction.
Is there a specific name for these types of clutches that allow for limitation in one direction, but no limitations or alternative limits in the opposite?
Size is not an issue at all for me, I just need something cheap. Limiter can be implemented on the sprocket, input shaft, or output shaft.
Does anyone have any suggestions to get me started in the right direction?
Thanks!





RE: Torque Limiting Clutches
http://www.bostongear.com/products/clutch/selectin...
Ted
RE: Torque Limiting Clutches
Functionally, @30in-lb I need the clutch to allow my output shaft to turn freely so that it doesn't burn my motor up after it has torqued to 30in-lb. Then motor will need to unscrew the lid off my valve. I calculated that the torque to unscrew my lid was about 5-7.5in-lb less then what is required to tighten it. So a bidirectional torque limiter should work, however its not necessary. I am only concerned to getting the lid on my valved tightened properly.
RE: Torque Limiting Clutches
RE: Torque Limiting Clutches
In practice you may find that loosening the cap will require more initial torque than the tightening torque.
Ted
RE: Torque Limiting Clutches
RE: Torque Limiting Clutches
You might want to check your torque calculations. I can't recall ever finding a screw that was easier to break loose than it was to tighten.
You also might want to build in a big fudge factor on the torque. Valve mechanisms and such tend to stick, badly, when left alone for periods like two weeks. Maybe you want to size the motor and drive so as to be just barely not quite strong enough to break the valve shaft. Then you don't need a clutch, and you can use a fuse as your ultimate torque limiter.
Mike Halloran
Pembroke Pines, FL, USA
RE: Torque Limiting Clutches
Best regards, David
RE: Torque Limiting Clutches
http://catalog.machinecomp.com/item/constant-torqu...#
Ted
RE: Torque Limiting Clutches