Patent ID: 6034497
Filing Date: 2000-03-07
Classification: H02H

Abstract:
An apparatus for detecting pinching of an object in a power window comprising:a motor for opening and closing a window over a predetermined travel range via a window driving mechanism;a motor driving unit for driving the motor;a pulse generating unit for generating a pulse corresponding to the rotation of the motor;a microcomputer control unit for performing a whole control driving process; andan operation switch for opening and closing the window by manual operation;wherein the whole travel range of the window being equally divided into a plurality of travel regions, and a base value, a tolerance value, and a reference value which is a value obtained by adding the base value and the tolerance value being set for each travel region, and the microcomputer control unit for sequentially detecting motor torque values for opening and closing the window, comparing the detected motor torque value with the reference value which is preset for the travel region in which the window is positioned, determining the pinching of an object when the motor torque value exceeds the reference value, and stopping or reversely rotating the motor,wherein the microcomputer control unit calculates a correction factor as a ratio between the motor torque value detected in an arbitrary travel region and the base value set for the travel region and, in case of determining the presence or absence of the pinching of an object in the travel region next to the arbitrary travel region, the microcomputer control unit uses a corrected reference value obtained by multiplying the reference value by the correction factor in place of the reference value set for the next travel region.