Automatic air coupling for a rail vehicle, in particular in the form of a goods wagon, having a mouthpiece for coupling the air coupling to an opposite air coupling; having a compressed-air connector for connecting the air coupling to a rail vehicle compressed-air system; having a flow channel which connects the mouthpiece to the compressed-air connector so as to conduct compressed air; having a valve which is arranged in the flow channel and which has a valve body (4.1) and a valve seat (4.2), wherein the valve body (4.1) is movable between an open position, in which it at least largely or completely exposes the flow channel, and a closed position, in which it shuts off the flow channel in a pressure-tight manner; having a valve drive which acts at least indirectly on the valve body (4.1) in order to actuate the latter from the open position into the closed position and/or from the closed position into the open position; wherein the valve drive comprises a shaft (5.1) which is rotatable about an axis of rotation, which is designed for non-rotatable connection to a rail vehicle coupling lock or is formed by a rail vehicle coupling lock and is provided with at least one cam (5.2), which acts at least indirectly on the valve body (4.1) to actuate the latter; wherein at least one position sensor, which detects a rotational position of the cam (5.2) at least indirectly, is provided in the region of the cam (5.2); characterized in that the at least one position sensor is designed as a non-contact sensor and the air coupling comprises a housing, which forms the flow channel and encloses the cam (5.2) over its external extent, at least in the circumferential direction relative to the axis of rotation, wherein the at least one position sensor is carried by the housing. having a mouthpiece for coupling the air coupling to an opposite air coupling; having a compressed-air connector for connecting the air coupling to a rail vehicle compressed-air system; having a flow channel which connects the mouthpiece to the compressed-air connector so as to conduct compressed air; having a valve which is arranged in the flow channel and which has a valve body (4.1) and a valve seat (4.2), wherein the valve body (4.1) is movable between an open position, in which it at least largely or completely exposes the flow channel, and a closed position, in which it shuts off the flow channel in a pressure-tight manner; having a valve drive which acts at least indirectly on the valve body (4.1) in order to actuate the latter from the open position into the closed position and/or from the closed position into the open position; wherein the valve drive comprises a shaft (5.1) which is rotatable about an axis of rotation, which is designed for non-rotatable connection to a rail vehicle coupling lock or is formed by a rail vehicle coupling lock and is provided with at least one cam (5.2), which acts at least indirectly on the valve body (4.1) to actuate the latter; wherein at least one position sensor, which detects a rotational position of the cam (5.2) at least indirectly, is provided in the region of the cam (5.2); characterized in that the at least one position sensor is designed as a non-contact sensor and the air coupling comprises a housing, which forms the flow channel and encloses the cam (5.2) over its external extent, at least in the circumferential direction relative to the axis of rotation, wherein the at least one position sensor is carried by the housing.