Selecting a Motor: Formulas for Calculating Load Torque TL [N·m] by Drive Mechanism
Formula for Load Torque
Ball Screw Drive
Pulley Drive
Wire and Belt Drive, Rack-and-Pinion Drive
Actual Measurement Method
- F
- Operation Direction Load [N]
- F0
- Preload [N] (≒ 1/3F)
- µ0
- Internal Friction Coefficient of Preload Nut (0.1~0.3)
- η
- Efficiency (0.85~0.95)
- i
- Speed Reduction Ratio (This is the speed reduction ratio of the mechanism and not the gear ratio of the Oriental Motor's gearhead)
- PB
- Ball Screw Lead [m/rev]
- FA
- External Force [N]
- FB
- Force When Main Shaft Begins to Rotate [N] (FB = Spring Balance Value [kg] × g [m/s2])
- m
- Total Mass of Table and Load [kg]
- µ
- Friction Coefficient of Sliding Surface
- θ
- Inclination Angle [˚]
- D
- Final Pulley Diameter [m]
- g
- Gravitational Acceleration [m/s2] (9.807)
Motor Sizing Service Information
We offer an easy to use motor sizing tool and optimal products sizing and selection service by our dedicated staff (free of charge).
Motor Sizing Tools
This tool lets you select a product by simply entering the values of the mechanism and operation conditions online. There are 7 mechanism for selecting motors of all categories.
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We will perform the time-consuming load calculation and motor sizing on your behalf, providing a response in as little as 2 hours.