Shock wave generator for an extracorporeal lithotripsy device

A shock wave generator for extracorporeal lithotripsy comprising:

• a housing having a volume filled with a shock wave transmissive medium;
• a membrane assembly closing one end of said volume and including a carrier disposed adjacent said volume and having a perimeter at least a portion of which is held to said housing and an electrically conductive section held to said carrier distal said volume and spaced from said perimeter, said perimeter having a substantially elastically yielding region;
• a high voltage supply;
• an insulating foil;
• an electrically conductive coil attached to said housing and having winding arranged in a surface parallel to said membrane assembly on the side of said carrier to which said electrically conductive section is held with said insulating foil disposed between said coil and said electrically conductive section, said coil having terminals connected to said high voltage supply so that said coil generates a magnetic field in a first direction, said electrically conductive section of said membrane assembly being electrically insulated from said terminals of said coil and said windings of said coil;
• said coil inducing a current in said electrically conductive section of said membrane assembly to generate a magnetic field in a direction to repel said membrane assembly from said coil to generate a shock wave in said medium.