Patent ID: 8430898

Claim:
A surgical instrument, comprising: a transducer configured to provide vibrations along a longitudinal axis at a predetermined frequency, the transducer comprising: a piezoelectric stack positioned along the longitudinal axis; a first metallic end mass positioned along the longitudinal axis adjacent a first end of the piezoelectric stack; a second metallic end mass positioned along the longitudinal axis adjacent a second end of the piezoelectric stack, wherein the length of the transducer is greater than or equal to ¼ of one wavelength and less than ½ of one wavelength; and an end effector extending along the longitudinal axis coupled to the transducer at a location offset from a nearest anti-node, wherein a length of the end effector is a non-integer multiple of ½ of one wavelength, and wherein a sum of the length of the transducer and the length of the end effector is an integer multiple of ½ of one wavelength.