engineering mags - pneumatic vs. electric motor question...

[crashnburn'd]

Too late to ask a professor and need to present this tomorrow... Trying to finish a project where I need an pneumatic motor instead of electric.

Question - Do pneumatic motors behave the same way as electric motors when they hit there stall torque? I realize they'll stall, but anyone know what happens inside, do seams blow, parts break, or do they just stop? Also, what happens to the air pressure in the lines in?

[Blizzard7763]

Theoretically nothing bad will happen. When it reaches the stall torque, the out valve opens, and keeps the pressure inside the cylinder at whatever the max pressure is. When the valve on the in line is opened, the pressure in the line will drop.

It's been a few years though, so don't trust your presentation on me.

[Big Blue]

Yeah, the max input pressure that is specified for a motor should be set low enough that no damage will occur in this scenario.

[crashnburn'd]

Theoretically nothing bad will happen. When it reaches the stall torque, the out valve opens, and keeps the pressure inside the cylinder at whatever the max pressure is. When the valve on the in line is opened, the pressure in the line will drop.

It's been a few years though, so don't trust your presentation on me.

This is what I figured, but I'm a little more knowledgable about the electric motors... I suppose I should actually try to find some documentation tomorrow morning. I'm sure my group/professor would be real happy when I tell them I wasn't sure, so I asked someone on the internet in a skiing forum....

[AltaPowderDaze]

ARO rotary-vane pneumatic power motors are designed to be used in a fixed position and remotely controlled. They provide all the safety, convenience and reliability of portable handheld air tools. In proportion to their power output they are small and light, and can be installed in confined spaced which cannot accept conventional electrics motors. They allow positive control at adjustable speeds. They are free from spark hazard and will not burn out from overloading. An overload motor will stall, but will return to normal operation when the overload condition is removed.
from here

[Hicks]

No problems when stalled, they are just less precisely adjustable than electric drives. Only point on linear pneumatic drives is that the rod can break on off-centered loads when suddenly arrested at high velocities.