Patent ID: 8206410

Claim:
An ultrasonic transducer unit configured to be attached to and detached from a handle section including at least one contact-point, the ultrasonic transducer unit comprising: an ultrasonic transducer configured to generate ultrasonic vibration; a transducer cover including a storing section which stores the ultrasonic transducer; a connection cylindrical portion disposed to a distal end of the transducer cover and adapted to be attached to and detached from the handle section; at least one electric contact portion provided on an outer peripheral surface of the connection cylindrical portion and being in a conductive connection with the contact-point of the handle section when the ultrasonic transducer unit is connected to the handle section; and at least one insulative projection portion provided on the connection cylindrical portion and provided at a distal end side of the electric contact portion and projects more radially outward than an outer peripheral surface of the electric contact portion.