Patent ID: 7859272

Claim:
A method for measuring a speed of a conductor slipping through a capacitive sensor, the method comprising: (a) sampling a value of a capacitance of a sensing electrode at each preset time; determining a first threshold value and a second threshold value according to a peak value of the capacitance when the value of the sampled capacitance reaches the peak value; obtaining a first time point when the value of the present sampled capacitance reached the first threshold according to the sampled values sampled by the step (a); obtaining a second time point when the value of the present sampled capacitance reached the peak value according to the sampled values sampled by the step (a); obtaining a third time point when the value of the present sampled capacitance reached the second threshold according to the sampled values sampled by the step (a); and determining the present speed of the conductor slipping through the capacitive sensor by a first period and a second period, wherein the first period is defined as a period of time from the first time point to the second time point, and the second period is defined as a period of time from the second time point to the third time point.