Patent ID: 8291936

Claim:
A nonreturn valve, comprising: a first tube connection housing having an inlet channel, an inlet chamber connected to the inlet channel and an annular valve seat surrounding the inlet chamber; and a second tube connection housing coupled with the first tube connection housing, wherein said second tube connection housing includes an outlet channel; an outlet chamber connected to the outlet channel; grooves; and recesses fluidly connecting at least one of the grooves with the outlet channel; a diaphragm disk between the two tube connection housings and made of flexible material, said diaphragm disk including an annular protrusion arranged outside of the annular valve seat and configured to be received in mutually opposite annular grooves of the first and second tube connection housings; and a plurality of openings arranged radially between the annular valve seat and the annular protrusion; a plurality of supporting walls spaced circumferentially about the outlet channel in the second tube connection housing for supporting the diaphragm disk and arranged opposite to the openings, respectively; a support directly connected with the supporting walls in the second tube connection housing and protruding toward the diaphragm disk; and ribs disposed on a surface of the support and extending beyond an outer periphery of the support, wherein the disk is adapted to be lifted from the annular valve seat toward the second tube connection housing upon an overpressure in the inlet channel, the disk is adapted to be pressed onto the valve seat upon an overpressure in the outlet channel, and the supporting walls and the grooves radially extend toward a center of the support.