Abstract: A water system is provided for an extracoporeal lithotripter. The reflector is aimed downwardly and has a spark gap at the first focus point thereof for generating a shock wave. A rubber diaphragm spans the lower end of the reflector. A water reservoir is provided along with pipes and a pump for circulating water from the reservoir to the reflector and back. A vacuum pump maintains pressure below ambient in the reservoir, the reflector and connecting pipes to control downward ballooning of the diaphragm.

Abstract: An extracorporeal lithotripter is provided with an ultrasound transducer on the rotational center line of the reflector and substantially at the open end of the reflector. The transducer is protected against shockwaves by a metallic housing in which it is mounted. The transducer at one end engages the housing through a resilient plastic disk, and is spaced laterally from the housing by a rubber O-ring adjacent the open end of the housing. The housing directly shields or shadows the transducer so that shockwaves are not transmitted to the transducer, which could damage the transducer and shorten its life.