Continuous "Combination scale" prepackaged metering devices are mainly electronic belt and spiral scales. Electronic belt suitable for packing powder materials. Mainly by the hopper, conveyor equipment, measurement scales, sensors, controllers and chassis weighing adjust other components. It works as follows: When the material from the hopper by automatic flow control valve on the conveyor belt, the continuous operation of the conveyor belt of uniform material to the weighing platform, belt scales measure the weight immediately on that segment of the belt material, and the material density changes into electrical signals transmitted by the sensor weighing adjustment control, the control automatically adjusts the opening of the grain hopper gates to ensure the stability of the material flow. Then by the synchronous operation of electronic scales and belt aliquot disk within a certain range of the material on the conveyor belt scale component equal amount into the filling falls bags, complete metering automatic blanking. Spiral scale for adhesion and bagging does not produce particulate materials. "Combination scale" mainly from the hopper, a servo motor, a screw feeder, baffles, sensors, controllers and adjusting chassis and other components. Its working principle is: servo motor driven screw feeder rotates, the material from the hopper and screw feeder to move forward through the feed opening fall on the bezel; vertical component materials can baffle momentum through sensor is converted to electrical signals to the adjustment control by adjusting the controller to adjust the servo motor speed control, change the flow of materials. Because momentum is proportional to the intensity of the output signal and Logistics "Combination scale" of the sensor, it is possible to ensure that the material flow stability, achieve accurate timing measurement purposes. And then the screw scale synchronous operation within aliquots plate screw feeder the material introduced into a certain range equal amount falls component filling bags, automatic blanking complete metering