FIELD: control of flow of fluid medium in one direction to prevent its flow in opposite direction in precombustion chambers of internal combustion engines. SUBSTANCE: check valve has body with inlet and outlet passages, valve member and seat. Intermediate passage having lesser diameter is made in the body between inlet and outlet passages. Seat is located on the outer side of intermediate passage. Valve member has spherical form and is located in outlet passages for motion between first position on seat and second position at some distance from seat. valve member moves to first position at back pressure in outlet passage exceeding the pressure in inlet passage. Outlet passage is cylindrical in shape. Area of cross section of intermediate passage is equal to area of flow of fluid medium between seat and valve member at its second position which is necessary to maintain the preset rate of flow. Area of flow of fluid medium in circular clearance between valve member and inner surface of outlet passage is equal to double area of flow between this valve member and seat which is necessary to obtain preset rate of flow. According to second version of invention, precombustion chamber of internal combustion engine includes check valve is described above. Check valve is used for control of delivery of gaseous fuel to precombustion chamber. EFFECT: enhanced reliability of control of flow of fluid medium. 6 cl, 4 dwg
