drawoh
Mechanical
- Oct 1, 2002
- 8,968
Does anyone know where I can find literature on how to analyze ACME threads for strength?
I have an actuator with a 1/2-10ACME threaded rod moved in and out by a threaded gear. The gear is PTFE impregnated delrin and the rod is stainless steel. We stripped the threads of one of our gears on the prototype by running it past the end of its travel. I am tempted to change the gear from delrin to leaded bronze, and the thread to 5/8-8ACME.
I am worried about the gear/nut stripping due to malfunctioning controls or rough handling. The gear is not vulnerable to the rough handling.
I have done a very crude, conservative estimate by assuming that one thread holds the entire load, that it strips at the root of the nut (major diameter), and that the root thickness is one half the pitch.
This thing is an actuator, so I am concerned about _any_ damage that might occur, not just a complete shear failure.
JHG
I have an actuator with a 1/2-10ACME threaded rod moved in and out by a threaded gear. The gear is PTFE impregnated delrin and the rod is stainless steel. We stripped the threads of one of our gears on the prototype by running it past the end of its travel. I am tempted to change the gear from delrin to leaded bronze, and the thread to 5/8-8ACME.
I am worried about the gear/nut stripping due to malfunctioning controls or rough handling. The gear is not vulnerable to the rough handling.
I have done a very crude, conservative estimate by assuming that one thread holds the entire load, that it strips at the root of the nut (major diameter), and that the root thickness is one half the pitch.
This thing is an actuator, so I am concerned about _any_ damage that might occur, not just a complete shear failure.
JHG