Abstract: An automatic train coupling includes: a coupling head including a coupling head housing and a coupling fastener, the coupling fastener being a rotary fastener including a coupling eyelet and a core, the core being rotatable between coupled and decoupled positions, the coupling eyelet by way of its first end being connected to the core such that the coupling eyelet is rotatable, the core including a throat; and a decoupling installation which is configured for being electrically, hydraulically, or pneumatically activated and which includes a motor that, by way of a drive connection of the automatic train coupling, is at least indirectly connected to the core so as to rotate the core from the coupled position to the decoupled position, the decoupling installation being disposed either completely within the coupling head housing or completely within the coupling head housing and a coupling bar adjoining the coupling head housing.