Filling nozzle

A filling nozzle, comprising an inlet (13) for a connection of a fluid supply line, an outlet (14) for dispensing the fluid, a fluid duct (15) connecting the inlet to the outlet, a main valve (16) that is situated in the fluid duct (15) and is preloaded into a closed position against a valve seat, a hand lever (17) for actuating the main valve (16), and a coupling device (22) that is operatively connected to the hand lever (17) and is designed, in a coupled state, to convert a movement of the hand lever (17) into an actuation of the main valve (16), wherein the main valve (16), in an uncoupled state, is pushed into the closed position independently of the position of the hand lever (17), wherein the filling nozzle also has a diaphragm (26) that separates a first diaphragm space (27) from a second diaphragm space (28) and can be moved to actuate the coupling device (22) by means of a pressure difference existing between the first diaphragm space (27) and the second diaphragm space (28), wherein a vacuum can be applied to the first diaphragm space (27), and wherein a sensor line (19) opens into the first diaphragm space (27), characterized in that the second diaphragm space (28) is sealed off from the fluid duct (15) and is fluidically connected via at least one ventilation duct (29) to surroundings outside the filling nozzle, wherein the fluid flows around a part of the coupling device (22) situated outside the second diaphragm space (28) when the main valve (16) is open.