A pressure reducing valve includes a first screw member on which a nut for adjusting the spring force of a pressure regulating spring travels, and a second screw member screwed into the first screw member and provided with a stopper for limiting the travel range of the nut at the tip. The second screw...http://www.google.es/patents/US5452741?utm_source=gb-gplus-sharePatente US5452741 - Pressure reducing valve
