[Mike Betts]

Originally Posted by joek

a window motor is not gonna lift a robot without being geared down a lot

Joe,

OK. Let's see if the math supports your statement...

The previous poster stated that he connected a shaft directly to the window motor. The most likely would be a 3/8" diameter...

The spec sheet for the Nippon-Denso gives a stall torque of 10.6 N*m. Now, the maximum power for a DC motor will occur at 1/2 speed and this give a torque of 5.3 N*m or 3.9 ft*lb or 46.9 in*lb.

The radius of the shaft is 3/16" which gives us a lifting force of (16*46.9)/3 = 250 pounds...

Cool!

I will leave it as an exercise for the student to calculate the speed of the lift and as an exercise for the testers to determine if the internal PTC resistor will interfere with lifting operations...

Regards,

Mike