Accurate　modeling　of　the　vibration　signal　model　of　planetary　gearboxes　is　essential　for　the　subsequent　fault　diagnosis.　According　to　the　existing　improved　phenomenological　model　based　on　the　meshing　vibration,　this　paper　conducts　further　investigations　on　the　vibration　mechanism　of　the　gearbox.　The　time　delay　phenomenon　of　faulty　ring　gear　tooth　participating　in　meshing　is　theoretically　analyzed,　and　the　assisted　phases　for　experimental　verification　are　proposed　and　deduced.　Based　on　the　improved　model,　the　vibration　signal　under　the　fault　condition　is　simulated　and　compared　with　the　results　of　traditional　methods.　Subsequently,　the　paper　proposes　to　divide　and　reconstruct　this　signal　and　use　the　maximum　correlation　kurtosis　deconvolution　(MCKD)　to　enhance　its　impact　characteristics.　The　results　show　that　the　phase　between　the　fault　impact　and　its　adjacent　meshing　impact　is　consistent　with　the　proposed　assisted　phase.　Finally,　the　correctness　of　the　vibration　mechanism　and　the　improved　phenomenological　model　are　verified　experimentally.