[en] At the Japan Proton Accelerator Research Complex, a new experimental facility called the Transmutation Experimental Facility (TEF) is planned for the Accelerator-Driven System. The TEF facility will use the 400 MeV proton beam from the LINAC, which requires introducing a beam dividing system at a Beam Transport from the LINAC to the 3 GeV Rapid Cycling Synchrotron (RCS). However, an early feasibility study indicates that sufficient beam orbit separation is difficult to obtain at the doublet with only a pulsed bending magnet. Therefore, the beam for the TEF is extracted by using both the pulsed bending magnet and a static septum magnet. To optimize this two-step beam extraction scheme, the doublet quadrupole magnets should be improved. Moreover, the residual field of the pulse bending magnet at zero current should be corrected. By studying every possible scheme for the beam dividing system under current conditions, we expect to obtain a realistic design for the beam dividing system. In this paper, we introduce a conceptual design of the beam dividing system that is based on resent results of studies of realistic designs. (author)