ASSEMBLED DRILL Russian patent published in 2016 - IPC B23B51/00 

FIELD: machine building.

SUBSTANCE: invention relates to machine building and can be used in machining materials by composite drill bits with mechanical attachment of cutting plates. Assembled drill comprises body with stem with lengthwise axis aligned with drill axis, chip removal flutes and seats are installed and fixed by fastening screws identical peripheral cutting plate and central cutting plate, each of which is limited by end surfaces in form of polygons and side surface. In one seat with central cutting plate there is additional cutting plate, which is made from material strength exceeding strength of central and peripheral cutting plates, has fastening part and at least one cutting part and is limited by at least one base surface for interaction with base body seat thrust wall for installation of central cutting plate, first side bearing surface for interaction with side supporting wall of said body seat second lateral bearing surface for interaction with additional thrust wall made in said body seat, and at least one fastening surface on attachment part for interaction with side surface of central cutting plate.

EFFECT: higher efficiency due to possibility of operation with increased drill feed.

3 cl, 12 dwg