Ultrasound Transducer with a Dumbbell-Shaped Chamber

摘要

An ultrasound transducer (2, 3, 4) has a cup-shaped casing (20, 30, 40). The cup-shaped casing has a sidewall (200, 300,400). A cross section of an inner surface of the sidewall (200, 300, 400) being perpendicular to a central axis of the ultrasound transducer (2, 3, 4) substantially shows a dumbbell-shaped contour. The dumbbell-shaped contour has a pair of opposite straight-line sections being substantially parallel to a longitudinal axis of the dumbbell-shaped contour and a pair of opposite arc sections being located respectively at two ends of the longitudinal axis of the dumbbell-shaped contour and respectively forming two enlarged portions of the dumbbell-shaped contour. Two ends of each arc section of the dumbbell-shaped contour respectively joint the straight-line sections through two curve sections and each curve section is connected to one end of the arc section and one straight-line section. At least one enlarged area of a dumbbell-shaped surface of an inside bottom surface has a recessed portion (3020, 4020).