Abstract: A weighing apparatus comprise a large throw-in weighing hopper which is fed with objects having a weight which is less than a target weight of the objects, holds the objects which are weighed, and discharges the weighed objects; a plurality of medium throw-in weighing hoppers which are respectively fed with the objects having weights adjusted with a different ratio, hold the objects for which combination calculation is performed based on the weights of the objects, and discharge the objects based on a result of the combination calculation; and a loss-in weight hopper which is used in loss-in weighing and performs loss-in discharge of the objects.

Abstract: A weighing apparatus (100) comprise a large throw-in weighing hopper (21) which is fed with objects having a weight which is less than a target weight of the objects, holds the objects which are weighed, and discharges the weighed objects; a plurality of medium throw-in weighing hoppers (64, 65, 66, 44) which are respectively fed with the objects having weights adjusted with a different ratio, hold the objects for which combination calculation is performed based on the weights of the objects, and discharge the objects based on a result of the combination calculation; and a loss-in hopper (42) which is used in loss-in weighing and performs loss-in discharge of the objects.

Abstract: A piezoelectric electro-acoustic transducer eliminates a negative influence caused by metal terminals upon the sound pressure and resonant frequency characteristics even when size and thickness reduction of the transducer are made. The transducer includes a piezoelectric diaphragm which includes a piezoelectric ceramic plate and a metal plate stored in a casing. The transducer also includes metal terminals in contact with the piezoelectric diaphragm and extending to the outside of the casing. The modulus of elasticity X of one metal terminal is specifically determined to be within a range defined by: ##EQU1## where E (N/m.sup.3) is the Young's modulus of one metal terminal in contact with a piezoelectric element, b (mm) is the width of part of the metal terminal extending from the inside of the casing to the outside thereof, h (mm) is the thickness of the metal terminal, and L (mm) is the length of the metal terminal.

Abstract: A piezoelectric electro-acoustic transducer has a substantially decreased resonant frequency without having to modify the size of a piezoelectric diaphragm or the shape of casing members used therein. The piezoelectric electro-acoustic transducer has a piezoelectric diaphragm including a metal plate and a piezoelectric ceramic disc disposed on one surface of the metal plate, wherein the piezoelectric diaphragm is to be supported at its periphery. A plurality of projections are specifically provided for stress transmission suppression at the periphery of the piezoelectric diaphragm in order to suppress or eliminate occurrence of circumferential transmission of a stress at the periphery during activation of the transducer.