Ultrasound transducer shielding

Claim 1

In an extracorporeal lithotripter comprising a truncated ellipsoidal reflector open at one end, a rubber diaphragm closing said open end, said reflector having a first focus point within said reflector and a second focus point outside said reflector and beyond said diaphragm, said reflector having an axis of rotation which passes through both of said focus points, said reflector and said diaphragm comprising a volume filled with water, a pair of electrodes in said reflector and having ends in spaced relation providing a spark gap at said first focus point, an electrical spark between said electrodes across said gap producing shockwaves focused by said reflector on said second focus point, the improvement comprising an ultrasound transducer within said reflector and aimed toward said second focus point, and a dense housing for said transducer, said housing being supported from said reflector adjacent said reflector open end and having a tapered end disposed toward said spark gap to deflect said shockwaves, said housing having an open end and a bore opening at said housing open end and aimed toward said second focus point, said bore having an inner end, said transducer being mounted in said bore and laterally spaced therefrom, resilient means interposed between said transducer and said bore inner end for cushioning said transducer, and additional resilient means substantially at said housing open end for spacing said transducer laterally from said housing for retaining and positioning said transducer.