| 摘要 |
PROBLEM TO BE SOLVED: To provide a rope trolley type unloader and a control method of the same which can bring a grab bucket into a closed state reliably when allowing the grab bucket to traverse without using a mechanically complicated mechanism.SOLUTION: A rope trolley type unloader comprises: a trolley traveling on a girder and a boom; a grab bucket suspended from the trolley; first, second, third, and forth drive mechanisms for allowing the grab bucket to rise with respect to the trolley, open and close, and traverse with the trolley; and a control unit for controlling the first, send, third, and forth drive mechanisms. For each motor of the first to forth drive mechanisms, the control unit has a speed controller and a current control system individually. Also, when allowing the grab bucket to traverse with the trolley, the control unit determines a deviation of the current value of the current control system for a corresponding support motor as well as an opening/closing motor, and performs synchronization control so as to synchronize the speeds of the support and the opening/closing motor based on the deviation. |
