| 摘要 |
PURPOSE:To measure the content of clay in molding sand mechanically, automatically and continuously with high accuracy by supplying electric current through the molding sand between the electrodes inserted into the molding sand under moving and detecting the electric resistance value at that time. CONSTITUTION:The lower parts of electrodes 3, 3 mounted with electric insulators 4, 4 to a supporting member 5 mounted to a stationary frame 6 are dipped into molding sand which moves on a belt 1 of a belt conveyor while the sand is regulated with guiding members 2, 2. Voltage is applied between the electrodes 4 and 4 to run electric current through the molding sand. The total electric resistance value R of the molding sand when the current flows is measured; at the same time, the temp. and moisture of the molding sand are measured with a tamp. sensor 11 and a moisture measuring sensor (not shown). From these measured values, the electric resistance relating to the content of clay is determined by subtracting resistance factors such as temp., moisture, intrinsic values in the molding sand and the like from the above-mentioned value R by an operator (not shown), and further the content of clay is calculated. |
