CONTROL SYSTEM FOR AUTOMATIC REVOLVING POSITION DETERMINATION OF UPPER REVOLVING SUPERSTRUCTURE

摘要

PURPOSE:To prevent the occurrence of danger due to maloperation as well as simplify operations by even beginners by a method in which a revolving superstructure is automatically stopped at a stop position by presetting a base point for angle detection by a start switch. CONSTITUTION:A start switch 15 is made at a desired revolving stop position by an operator, a revolving operation lever 11 is operated, and a spiral is revolved to an excavating position for excavation. After excavation, the revolving superstructure is operated to the returning direction, and the lever 11 is restored to neutral position at near 20-50 deg. before the starting point. An automatic control system sends out a braking signal, the present revolving speed and position are calculated from signals from a revolving angle sensor 7 by a controller 14, and they are detected by a memory circuit 19. Control signals are always corrected, oil pressure in a braking pipe is controlled by an electromagnetic hydraulic control valve 10 and braking force is adjusted to stop smoothly a revolving motor 4 at the starting point.