ANTI-PINCHING DEVICE FOR POWER WINDOW

摘要

PPROBLEM TO BE SOLVED: To provide an improved anti-pinching device for a power window, which detects pinching of foreign matter by window glass from a change in motor current, and which limits the motor current by surely detecting an abnormal current, occurring in the motor current due to the pinching of the foreign matter, without false recognition. PSOLUTION: This anti-pinching device for the power window is equipped with a charge/discharge control circuit (3b) which keeps a value of a reference voltage Vc constant without reference to an On/Off operation of a semiconductor switch (SSW1) by controlling a first current source (AS1) and a second current source (AS2), so that the charge/discharge of a capacitor (C1) can be inhibited, when the motor current (ID) is increased due to the occurrence of the pinching and a charge/discharge control signal (CMP1_OUT) is kept at an L-level for a given length of time. Thus, on the occurrence of the pinching, a reference voltage Vins can be surely set at the value of the reference voltage Vc or below. PCOPYRIGHT: (C)2005,JPO&NCIPI