Patent ID: 9120647
Filing Date: 2015-09-01
Classification: B66B

Abstract:
1. An inverter for an escalator control device, comprising: a control unit, input terminals of which are connected to a passenger detector for detecting a riding of a passenger, and which may receive a detection signal from the passenger detector; a frequency inverting unit for inverting current frequency, input terminals of which are connected to the public electrical net, and which is connected with the output terminal of the control unit; a frequency inverting unit contactor, input terminals of which are connected to the frequency inverting unit, and output terminals of which are connected to a motor of the escalator; and a public electrical net contactor, input terminals of which are connected to a public electrical net, and output terminals of which are connected to the motor of the escalator; wherein the inverter is configured as that: when the escalator is running with low speed or is waiting with zero speed, the frequency inverting unit contactor is closed and the public electrical net contactor is open; and in this case, if the passenger detector has detected there is a passenger who is going to ride the escalator, the passenger detector sends a signal to the control unit, and the control unit then sends a signal of commanding high speed running to the frequency inverting unit, and the frequency inverting unit then increases the output current frequency to increase the running speed of the escalator; and when the running speed of the escalator reaches a predetermined nominal speed, the frequency inverting unit commands the frequency inverting unit contactor to be open and the public electrical net contactor to be closed, thus the motor of the escalator is switched from being driven via the frequency inverting unit to being driven directly by the public electrical net, and the escalator runs with the normal speed, and wherein the inverter further comprises: a delta connection contactor connected to the motor of the escalator to achieve a delta connection of the motor; and a star connection contactor connected to the motor of the escalator to achieve a star connection of the motor; wherein when a load of the escalator is smaller than a predetermined load threshold, the frequency inverting unit commands the delta connection contactor to be open and the star connection contactor to be closed; and when the load of the escalator is greater or equal to the predetermined load threshold, the frequency inverting unit commands the delta connection contactor to be closed and the star connection contactor to be open.