Medical pressure relief valve

Abstract

Pressure relief valve apparatus is disclosed for shunting fluids under conditions of overpressure, thereby preventing further increases in the pressure within a fluid delivery system. A presently preferred embodiment of the apparatus of the invention is formed of two components, a valve body member and a valve tube member. The valve body member is provided with first and second connector elements for use in connecting the pressure relief valve into a medical fluid delivery circuit. It is also provided with first and second bores passing through the first and second connector elements, respectively, and exiting at respective first and second exit ports on the side of the valve body member. A valve seat comprising a raised annular ridge around the circumference of the valve body member separates the first and second exit ports. The valve tube member is formed from an elastic material, preferably silicone tubing, and is placed in elastic tension over the valve body member so as to cover both exit ports and the valve seat. Under conditions of rest and low pressures, the valve tube member prevents fluid from passing between the two exit ports, but under conditions of overpressure, the valve tube member will stretch away from the valve seat, forming a gap therebetween through which fluid will flow.