In the strong short-ranged repulsion conditions the scattering picture of excitations is equivalent to the scattering of identical Fermi particles. In the wave lengths, large in comparison with the elementary cell dimensions (in Γ-point), the physical situation corresponds to the scattering of slow particles. For the latest case the scattering amplitude is positive always. With the energy increasing the scattering amplitude is decreases and changes his sign for momenta of order of inverse scattering centre dimension. In the crystal lattice the elementary cell dimension is the representative dimension. Hence we conclude that with energy increasing from Γ-point to the Brillouin zone boundary the scattering amplitude can to change the sign at the momentum of order of reciprical lattice vector . The negative sign of the scattering amplitude on the Fermi energy surface results to the normal state instability and the superconductivity condencate prescipitation. Therefore in the filling of lower Hubbard band the superconductivity begins from the some electrons finite concentration, corresponding to the amplitude sign change of the Fermi level.