SWING METHOD FOR SLEWING CRANE, SLEWING CRANE OUTRIGGER EXTENSION DETECTING MEANS, AND SWING POSITION DETECTING MEANS

摘要

PURPOSE: To stop an overloaded swing by, when a crane load is larger than a rated load, stopping the swing of an upper swing body to a swing area where a larger rated load is applied to the swing area where a smaller rated load is applied, and also prohibiting the swing of it in that direction. ;CONSTITUTION: A controller 1 in which a clockwise swing signal M is input outputs an electric signal to a clockwise swing signal line 5R in a hydraulic swing circuit 5 so as to swing an upper swing body clockwise from a stationary state. While a clockwise swing instruction is given, if the upper swing body is moved from a swing area (PLS) where a rated load for which the position of the crane load (P) is larger is applied to a swing area (PSS) where a rated load for which the position of it is smaller is applied, it is swung clockwise continuously based on a signal from swing position detectors 44F and 44B even in the swing area PLS when P≤PS (rated load). When PPS, the output of an electric signal to the clockwise swing signal line 5R is stopped to stop the clockwise swing, and subsequent clockwise swing is prohibited.;COPYRIGHT: (C)1996,JPO