SONIC ENERGY ROD TRANSDUCER Russian patent published in 2004 - IPC

FIELD: ultrasonic equipment, applicable in ultrasonic devices of industrial equipment for metal working, equipment for realization of other production processes.

SUBSTANCE: the transducer has a piezoelectric element in the form of a set of longitudinally polarized washers of piezoelectric ceramics, rod waveguide, front cover plate, concentrator and a back cover plate connected to the end surfaces of the piezoelectric element, and reinforced by the waveguide between each other. The back cover plate is made with a bulge and a central hole, exceeding the waveguide diameter. The waveguide has a mount on the supporting end, which is mechanically linked with the mount end. The fastening end of the waveguide is connected to the concentrator. The front cover plate and the concentrator are made integral. The cover plates are made of material with an acoustic resistance commensurable with the acoustic resistance of the piezoelectric ceramics with a difference up to 20%. The bulge height is determined by relation:

where: - the resonance resistance of the sonic rod transducer, Hz; - the thickness of the back cover plate, m; h - the height of the bulge on the back cover m; - the velocity of the longitudinal wave in the material of the back cover plate, m/s; - the velocity of the longitudinal wave in the waveguide material, m/s; n - the number of piezoelectric washers in the piezoelectric element, pc; - the thickness of one piezoelectric washer, m; - the velocity of the longitudinal wave in the piezoelectric ceramics, ms; The bulge of the back cover plate may be made in form of a truncated cone, whose diameter of the lesser base equals the diameter of the waveguide mount, and diameter of the larger base equals the outside diameter of the back cover plate. A washer of metal with a low velocity of the longitudinal wave is inlaid in the end of the bulge. A contracting cavity in the form of a truncated cone is made in the front cover plate and in the concentrator, its larger diameter is close to the inside diameter of the washers made of piezoelectric ceramics. The waveguide is made of metal with a level of the internal mechanical resistance lower than that of the cover plates.

EFFECT: enhanced electroacoustic efficiency.

5 cl, 3 dwg