Patent ID: 8841874
Filing Date: 2014-09-23
Classification: H02P

Abstract:
1. A method of detecting an operating condition of an electrical stepper motor, which comprises a magnetical rotor and at least two electromagnetical driving coils for causing the magnetical rotor to rotate, the method comprising: connecting one contact pin of at least one of the electromagnetical driving coils via a resistor to a defined voltage source during a non-activated state of the driving coil; detecting a voltage induced at the driving coil during the non-activated state and converting the detected voltage into a digital signal; and digitally analyzing the digital signal and deriving the operating condition of the magnetical rotor by evaluating a signal waveform including any positive and negative components of the digital signal, wherein a first contact pin of the driving coil is connected via a first resistor to an operating voltage, and a second contact pin of the driving coil is connected via a second resistor to a ground voltage during the non-activated state of the driving coil.