| 摘要 |
An anti-tightline control system and method which monitors the hoist and drag rope-in length of dragline type equipment, and in the event that certain preset levels are exceeded, the control system functions to slow the hoist and drag rope drives, initiate a warning to the operator of the dragline equipment, and if required, stops the hoist and drag rope drives. The control provides a limit to a voltage reference signal from the operator's hoist and drag master control for the hoist and drag drive motor voltage regulators under static or dynamic tightline operating conditions to automatically reduce the speed of both the hoist and drag rope drives towards zero as the amount of net rope-in increases. For certain specialized dragline equipments having specially-shaped tightline limit boundary characteristics, the control system makes available a function generator for establishing a shaped tightline limit boundary instead of the elliptical tightline boundary used with other types of equipment. Additional reference circuits are provided for converting the form of control signal derived at the output of the anti-tightline control system into a different form suitable for use with the form of signal required by a particular equipment. |
