Shock wave source for generating a short initial pressure pulse

US4879993A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Helmut Reichenberger · Eckental, DE
• Rudolf Schittenhelm · Erlangen, DE

Key dates

• Filing date: Oct 6, 1987
• Grant date: Nov 14, 1989
• Expiry date: Oct 6, 2007

Classification

• Technology area (CPC G): Physics
• CPC primary: G10K9/12
• WIPO field: Other consumer goods
• WIPO sector: Other fields

Abstract

A shock wave source has a coil carrier, a planar or concave coil, a membrane consisting of electrically conductive material and a foil consisting of electrically non-conductive material. The membrane is disposed between the coil and the foil so as to be held tightly therebetween but having a perimeter which is capable of substantially unrestrained movement. Upon the application of a high voltage pulse to the coil, the resulting field causes the membrane to be rapidly repelled, however, only the mechanical forces of the membrane act on the foil, with no electromagnetic forces generated by the coil acting on the foil. The resulting pressure pulse is intensified to form a shock wave pulse in a transmission medium adjacent to the foil. The substantially unrestrained perimeter of the membrane disposed between the coil and the foil permits an initial pressure pulse of short duration to be generated, which provides the further advantages of a short approach path, a small focus zone, a high focusing factor, low electrical and thermal stress on the shock wave source and a low acoustic energy output into the body of a patient receiving treatment using the shock wave source.