AUTOMATIC CONSTANT AMOUNT INJECTOR

PURPOSE:To make measuring errors hard to occur with a simple operation, by comparing a measured value, obtained with a weight measuring section, with an input value inputted to a set input section to output an opening or closing signal to an opening/closing valve when the measured value is below the input value or when it reaches the value. CONSTITUTION:A liquid tank 14 is arranged above an electronic scale 12 and an solenoid valve 16 as an opening/closing valve to control the dropping and injection of a lead acetate solution 7 in an injection tube 15 near an outlet section thereof 15; the opening or closing operation of the solenoid valve 16 is performed by an opening or closing signal from an opening/closing valve control section 17. Then, the opening/closing valve control section 17 compares a measured value, obtained with the electronic scale 12, with an input value inputted into a set input section and transmits an opening signal to the solenoid valve 16 when the measured value is below the input value while it transmits a closing signal thereto 16 when it reaches the input value. Thus, the lead acetate solution 7 is supplied at a specified rate to a brei 3 in a polyester cup 13 from the liquid tank 14.