Discharge circuit, and use thereof in a method and in apparatus for detecting and correcting the positions of electrodes, in particular as used in apparatuses for generating pressure waves

Claim 1

An electrical discharge circuit for providing a discharge between two discharge electrodes immersed in a liquid comprising means for intermittently connecting a voltage source across said two electrodes, and a non-mechanical electronic switch connected in parallel with said electrodes, said switch presenting a low impedance approximating a short circuit condition for low frequency currents approximating a direct current, and said switch presenting a high impedance approximating an open circuit condition for higher frequencies including during discharge.

Claim 9

A method of detecting and correcting the position of at least one electrode of a plurality of electrodes in an electrode discharge device said electrodes being intended for disposition at a predetermined distance symmetrically about a focal point in three dimensional space at which an electrical discharge is to be generated (a) providing a non-mechanical electronic switch connected in parallel with said electrodes, said switch presenting a low impedance approximating a short circuit condition for low frequency currents approximating a direct current during detection, and said switch presenting a high impedance approximating an open circuit condition for higher frequencies, including during discharge; (b) positioning a detector at a point, referred to as the detection point situated on the displacement path of the electrodes, which path includes said focal point, said detector detecting the presence of an electrode at a point in three dimensional space; (c) applying a low frequency current approximating a direct current to said detector; (d) advancing said at least one of the electrodes until it comes into contact with said detector while said detector is disposed at the detection point; (e) detecting the presence of said at least one electrode at said detection point by a change in resistance in the circuit comprising said detector and said electrode when contact therebetween is established; (f) withdrawing said at least one electrode to position said electrode at its predetermined distance about said focal point; (g) performing steps (b)-(f) with at least another electrode in said plurality of electrodes; and (h) withdrawing the detector from said detection point.

Claim 10

A method of detecting and correcting the position of at least one electrode of a plurality of electrodes in an electrode discharge device said electrodes being intended for disposition at a predetermined distance symmetrically about a focal point in three dimensional space at which an electrical discharge is to be generated (a) providing a non-mechanical electronic switch connected in parallel with said electrodes, said switch presenting a low impedance approximating a short circuit condition for low frequency currents approximating a direct current during detection, and said switch presenting a high impedance approximating an open circuit condition for higher frequencies, including during discharge; (b) positioning a detector at a point, referred to as the detection point situated on the displacement path of the electrodes, which path includes said focal point, said detector detecting the presence of an electrode at a point in three dimensional space; (c) applying a low frequency current approximating a direct current to said detector; (d) advancing said at least one of the electrodes until it comes into contact with said detector while said detector is disposed at the detection point; (e) detecting the presence of said at least one electrode at said detection point by a change in resistance in the circuit comprising said detector and said electrode when contact therebetween is established; (f) withdrawing said at least one electrode to position said electrode at its predetermined distance about said focal point; (g) performing steps (b)-(f) with at least another electrode in said plurality of electrodes; and (h) withdrawing the detector from said detection point.