Device for positioning on blade body and marking method thereof

The invention discloses a device for positioning on a blade body and a marking method thereof, the device is formed by assembling and connecting a clamping block, a first top block, a second top block and a positioning unit, the clamping block is a rectangular block body, and a mortise matched with a tenon of a tested blade in shape is formed in the surface of the top side of the clamping block; the two top blocks are fixed on the opposite surface of the clamping block through screws, each top block is provided with a boss matched with the non-working plane of the blade, the bosses and the mortises enclose and fix the tenons, the positioning units are arranged corresponding to the side walls, except the opposite surface, of the clamping block, and the positioning units are provided with marking tools which face the working surface of the blade and are perpendicular to the side walls. By means of the scheme, the device is simple in structure, positioning can be conducted at the designated position of the blade