Metering system capable of easily effecting high-accuracy metering for various works including sticky materials

A combination weighing machine for weighing an object of weighing, said machine comprising:

• an apparatus housing having a top portion;
• introduction hopper mean provided on the top portion of said apparatus housing, for introducing the object of weighing into said apparatus housing;
• a plurality of supply feeder means horizontally arranged in a straight line under said introduction hopper means, for feeding the object of weighing introduced in said introduction hopper means to a forward portion of said apparatus housing;
• a plurality of pool hopper means provided on said forward portion of said apparatus housing corresponding to said plurality of supply feeder means, for receiving the object of weighing with a predetermined quantity thereof fed by said plurality of supply feeder means;
• first base plate means for carrying said plurality of pool hopper means thereon, said first base plate means being relatively slidable with respect to said plurality of pool hopper means to temporarily store predetermined quantities of the object of weighing received individually by said plurality of pool hopper means and to supply the object of weighing to a lower stage thereof;
• a plurality of weighing hopper means provided under said first base plate means and corresponding to said plurality of pool hopper means, for receiving the object of weighing supplied from said plurality of pool hopper means to the lower stage by use of said first base plate means;
• a plurality of second base plate means, each for carrying said plurality of weighing hopper means thereon, each of said second base plate means including means for individually weighing said predetermined quantities of the object of weighing supplied correspondingly from said plurality of pool hopper means to said plurality of weighing hopper means, and each of said second base plate means being relatively slidably individually with respect to said plurality of weighing hopper means to supply a weighed object of weighing in selective combinations to a lower stage thereof;
• and
• collecting means for collecting said weighed object of weighing supplied in selective combinations from said plurality of weighing hopper means by use of said plurality of second base plate means,
• wherein each of said plurality of pool hopper means and said plurality of weighing hopper means comprises a hollow, bottomless straight barrel-type container, and each barrel-type container has a plurality of indentations on an inner peripheral wall thereof, said indentations extending along the length of the respective barrel-type container in the direction of the barrel axis thereof, said indentations each defining projections for contacting said object of weighing with substantially point contact to enable discharge of substantially all of said object of weighing from the respective barrel-type container, and
• said plurality of supply feeder means each comprises:
• a transportation screw provided in a guide path for transporting the object of weighing;
• a drive motor for intermittently rotating said transportation screw;
• and
• control means for controlling said drive motor so as to transport a predetermined quantity of the object of weighing from a proximal end side of said guide path to a distal end side of said guide path through said transportation screw,
• said control means including:
• means for causing said drive motor to forwardly rotate said transportation screw for a predetermined variable amount for thereby transporting the object of weighing, and said control means then stopping the forward rotation of said transportation screw for stopping movement of the object of weighing;
• and
• means for causing said drive motor to reversely rotate said transportation screw for at least one revolution after movement of the object of weighing is stopped.