The present invention relates to a brake device for a hoist electric motor of a tower crane, comprising: first to third auxiliary contacts (MV1, PV1, and GV1) which perform on / off operations in association with a motor speed adjusting switch; A first time relay TF1 that is excited after a predetermined time when any one of the first to third auxiliary contacts MV1, PV1, and GV1 is turned on: a first time relay TF1 that is turned on when the first time relay TF1 is excited First time relay contact TF1: Excited when the first time relay contact TF1 is turned on. First relay F1: Turned on when the first relay F1 is excited and turned on by the first rectifier 2-1. First relay contact F1 for supplying the applied DC power to the first brake disc coil 4-1: Fourth to sixth auxiliary contacts MV2, which perform on / off operations in conjunction with the motor speed adjustment switch. PV2, GV2): Second time relay TF2 which is excited after a certain time when any one of the fourth to sixth auxiliary contacts MV2, PV2 and GV2 is turned on: When the second time relay TF2 is Second time relay contact TF2 that is turned on when excited: The second relay F2 that is excited when the second time relay contact TF2 is turned on and: When the second relay F2 is excited And a second relay contact F2 for supplying the DC power applied from the second rectifier 2-2 to the second brazed disk coil 4-2, for the hoist motor during the speed conversion of the hoist motor. The braking device can be closed and then opened to prevent damage to the hoist motor.
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