Patent attributes
A magnetic substance holding device includes: a first pole piece assembly including a first N-pole piece, a first S-pole piece, and a first permanent magnet; a second pole piece assembly including a second N-pole piece, a second S-pole piece, and a second permanent magnet; at least one first coil; at least one second coil; and a control device controlling current applied to the first coil and the second coil so as to control magnetic fluxes passing through the first coil and the second coil, thereby allowing the first pole piece assembly and the second pole piece assembly to switch between the first arrangement and the second arrangement, to control magnetic fluxes passing through the holding faces of the first pole piece assembly and the second pole piece assembly.