PURPOSE: To count the number of parts efficiently by utilizing variation in measured torque when the parts are ejected from a metering and carrying mechanism.

CONSTITUTION: A belt conveyor device 1 is supported rotatably on a horizontal shaft 8 provided at the top of a fulcrum base 7 at one end part, and a balancing weight 9 is fitted in the extension direction of the conveyor device 1, permitting the conveyor device 1 to balance on the horizontal shaft 8. The other end of the conveyor device 1 is supported through a load detector 10 and the torque generated around the horizontal shaft 8 by parts A loaded on a belt 5 is measured electrically. A guide hopper 11 from which the parts A is thrown onto the belt 5 on the horizontal shaft 8 is provided over the horizontal shaft 8.