A hinge device base comprising a substrate having a first face, a first movable member provided on the first face so as to be capable of moving in a first direction along the first face with respect to the substrate, and a first position adjusting mechanism for adjusting a position of the first movable member in the first direction with respect to the substrate, and the first movable member is removably connected in use either indirectly or directly to a body part, which is rotatably connected to an attachment member; a shaft guiding recessed section and a fitting recessed section, which extends from the shaft guiding section, are formed on the first face of the substrate; as the first position adjusting mechanism, a substrate side guiding section (32, 10p) is provided on the shaft guiding recessed section, and a first adjusting shaft (31, 31X) is provided between the substrate and the first movable member, and the first adjusting shaft (31, 31X) has, in an integrated form, a first shaft part which rotatably engages to the first movable member around a first rotation axis line orthogonal to the first face and is inserted into the shaft guiding recessed section so as to be guided in the first direction, and a first shaft-side guiding section (31c, 31p) which engages with the substrate side guiding section (32, 10p); and a fitting section is provided in the first movable member, and the fitting section is inserted into the fitting recessed section so as to be able to slide in the first direction, wherein the first shaft part includes a cylindrical part, a disk part, and a projecting shaft part, where the disk part and the first shaft-side guiding section (31c, 31p) are housed in the shaft guiding recessed section, characterised in that the shaft guiding recessed section and the fitting recessed section have a front side edge and a back side edge in a second direction orthogonal to the first direction along the first face, and in that the front side edge and the back side edge of the shaft guiding recessed section roughly abut the disk part from both sides in the second direction, and the first adjusting shaft (31, 31X) is capable of moving in the first direction such that it is capable of being guided along the front side edge and the back side edge of the shaft guiding recessed section with respect to the substrate, and is not capable of moving in the second direction. a shaft guiding recessed section and a fitting recessed section, which extends from the shaft guiding section, are formed on the first face of the substrate; as the first position adjusting mechanism, a substrate side guiding section (32, 10p) is provided on the shaft guiding recessed section, and a first adjusting shaft (31, 31X) is provided between the substrate and the first movable member, and the first adjusting shaft (31, 31X) has, in an integrated form, a first shaft part which rotatably engages to the first movable member around a first rotation axis line orthogonal to the first face and is inserted into the shaft guiding recessed section so as to be guided in the first direction, and a first shaft-side guiding section (31c, 31p) which engages with the substrate side guiding section (32, 10p); and a fitting section is provided in the first movable member, and the fitting section is inserted into the fitting recessed section so as to be able to slide in the first direction, wherein the first shaft part includes a cylindrical part, a disk part, and a projecting shaft part, where the disk part and the first shaft-side guiding section (31c, 31p) are housed in the shaft guiding recessed section, characterised in that the shaft guiding recessed section and the fitting recessed section have a front side edge and a back side edge in a second direction orthogonal to the first direction along the first face, and in that the front side edge and the back side edge of the shaft guiding recessed section roughly abut the disk part from both sides in the second direction, and the first adjusting shaft (31, 31X) is capable of moving in the first direction such that it is capable of being guided along the front side edge and the back side edge of the shaft guiding recessed section with respect to the substrate, and is not capable of moving in the second direction.