Cap for safely filling and closing an engine oil tank, in particular of an aircraft engine

A cap (4) for safely filling and closing an engine oil tank (1), the cap (4) comprising an elongated tubular oil feed body (6) having a first end portion (8) fitted in a fluidtight manner to an inlet (3) of an engine oil tank (1);

• a removable cover body (25) for closing said first end portion (8);
• an oil feed valve (23) fitted to the tubular body (6) and movable between an open position, allowing oil flow into the tank, and a closed position, preventing oil outflow from the tank;
• and a dipstick (26) for measuring the oil level in the tank, and which is housed in said tubular body (6) and carried by said removable cover body (25);
• wherein said feed valve is located close to said first end portion, said cap also comprising a monostable valve (27) controlled by said dipstick (26),
• wherein
• said feed valve comprises a lateral opening (13) formed through said tubular body, said opening (13) extending in such a position as to have a passage portion unaffected by the oil and located above the maximum oil level (21) in the tank,
• said feed valve further comprises a movable flap (15) closing said opening,
• said movable flap is hinged to said tubular body to rotate about a hinge axis (18) perpendicular to an axis (7) of said tubular body, and
• said hinge axis extends above the oil level in said tank.