A LOAD CONTROL SYSTEM PREFERABLY FOR HYDRAULIC CRANES

摘要

A load control system preferably for hydraulic cranes comprising at least one relevant signalling device connected to a control unit which, by loading of the crane beyond its nominal load rate, operates a dump valve for deactivation of such functions in the manually operable control-valve assembly, which may be actuated to cause an increase of the load on the crane. The special feature of this load control system is that it operates according to an educational principle of collective "punishment", comprising a total inactivation of the functions of the crane in a penalty period in case of attempts to exceed the nominal load rate of the crane, within a safety margin. By an increasing load on the crane, the control system calculates new penalty periods and load rates beyond the nominal load rate within a safety margin, and the control system will induce a constantly increasing penalty period in response to the extent and number of excesses. The educational principle consists in that the risk of the release of a penalty will cause the operator to adopt a better feeling of how much the crane can be loaded within its nominal load rate.