jmueller065 wrote: It is an electric motor--there is no torque curve.
Actually yes there is a torque curve. There has to be or "power" could not increase.
If this motor only had 1 RPM what you're saying would be true. But it's a variable speed, thus variable torque motor. Otherwise all speed and power would be handled through a CVT transmission and not a single gear transmission. It is what I would refer to as torque crap out. It's there, right off the line, all of it, but it is not a all off the torque all of the time as commonly referred to.
The graph above shows a torque/speed curve of a typical D.C. motor. Note that torque is inversely proportioal to the speed of the output shaft. In other words, there is a tradeoff between how much torque a motor delivers, and how fast the output shaft spins. Motor characteristics are frequently given as two points on this graph:
The stall torque,[Ts], represents the point on the graph at which the torque is a maximum, but the shaft is not rotating.
The no load speed,[Wn], is the maximum output speed of the motor (when no torque is applied to the output shaft).
The linear model of a D.C. motor torque/speed curve is a very good approximation. The torque/speed curves shown below are actual curves for the green maxon motor (pictured at right) used by students in 2.007. One is a plot of empirical data, and the other was plotted mechanically using a device developed at MIT. Note that the characteristic torque/speed curve for this motor is quite linear.
This is generally true as long as the curve represents the direct output of the motor, or a simple gear reduced output. If the specifications are given as two points, it is safe to assume a linear curve.
Also note that the "100% torque available at any speed" can only be 100% available torque AT that speed. Note how fast the torque curve drops by RPM. I work on 4 pole brushless motors in my spare time. Torque to speed drop is about 60% torque loss per 10% rotational speed. What the motor lacks after 1000 rpm it makes up for in rotational speed at 6000 rpm.