Abstract
In calculating the braking torque of a brake, the braking efficiency method is often used. In this paper, the formulas for calculating braking torque of leading shoe and trailing shoe brake are analyzed. Although they are different in forms with different parameters, these formulas can be changed into the same form, which shows that they are identical. In fact these formulae are all based on the same hypothesis. What makes them different from each other is just the difference in integration variable and integrating range. Some proposals for choosing among them are also given in the end of the paper.