STOP DETECTOR, STOP DETECTION METHOD, AND SECURITY SYSTEM

• Main Authors: NAKAYAMA AKIYUKI, HIGUCHI TOSHIYUKI, AKAGI TETSUYA, HASHIMOTO MINORU, KAMIZONO DAICHI
• Format: Patent
• Language: English
• Published: 14.05.2009
• Subjects: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT; MEASURING; MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION,OR SHOCK; PHYSICS; TESTING

PROBLEM TO BE SOLVED: To increase the accuracy of stop detection of a motor by reducing the variations and errors in threshold setting to be used for determination of the stop of the motor. SOLUTION: Back electromotive force (BEMF) of the motor is detected. It is determined that the motor has stopped at the time t2 when a set time T has passed since the time t1 when the detected value of the BEMF became a first fixed threshold L1 or below. The set time T is set as a digital value by means of a digital setting switch. Unlike the conventional method, setting the threshold in analog volume is not necessary. COPYRIGHT: (C)2009,JPO&INPIT