METHOD FOR WEIGHING USEFUL LOAD IN HOISTING VEHICLE IN THE COURSE OF MOVEMENT AND DEVICE FOR EFFECTING THE SAME Russian patent published in 1994 - IPC

FIELD: mining industry. SUBSTANCE: method for in-motion weighing of useful load is based on measurements of electrical resistance of hoisting ropes, which varies depending on strain caused by loads on rope ends. Method involves specifying resistance values proportional to positions of empty and loaded vehicles, measuring resistances of ropes of empty and loaded vehicles, adding together respective values of specified and measured resistances and comparing complex values of these resistances. Mass of useful load is determined proceeding from the results of this comparison. Device for effecting the above method has flexure elements and measuring instrument containing null-indicators and bridge circuit with power source and potentiometers connected across the same pair of bridge terminals. Hoisting vehicles are fastened to hoisting ropes, which serve as flexure elements. Variable resistors comprising the first and second arms of bridge circuit are positioned along well in its opposite end faces. Their upper ends are not closed to form a unit and are positioned above the extreme upper position of hoisting vehicles. Value of resistance of variable resistors is equal to resistance of rope of hoisting vehicle, when it is in the extreme lower "suspended" position. Device for effecting the above method has flexure elements and measuring instrument containing null-indicators and bridge circuit with power source and potentiometers connected across the same pair of bridge terminals. Hoisting vehicles are fastened to hoisting ropes, which serve as flexure elements. Variable resistors comprising the first and second arms of bridge circuit are positioned along well in its opposite end faces. Their upper ends are not closed to form a unit and are positioned above the extreme upper position of hoisting vehicles. Value of resistance of variable resistors is equal to resistance of rope of hoisting vehicle, when it is in the extreme lower "suspended" position. Current collectors of potentiometers are in reliable electrical contact with hoisting ropes near points of their attachment to hoisting vehicles. Contacts sliding along ropes are located above the extreme position and are connected in one unit. Through measuring instrument with indicator they are connected to common point of ballast resistors forming third and fourth arms of bridge circuit as second diagonally opposite pair of bridge terminals. Variable resistors of potentiometers are connected to bridge circuit with the aid of current conducting busses. EFFECT: improved accuracy of in-motion weighing of loads. 3 cl, 2 dwg