▎ 摘　　要

NOVELTY - The utility model claims an inner-cooling drill for improving cooling property, comprising a handle and a drill bit; one end surface of the handle is fixedly connected with one end surface of the drill bit; the drill bit comprises a cutting part, a chip removing part and a cooling part; the cutting part comprises a bottom edge, a transverse edge; a chip cutting tooth and a blade belt; the chip discharging part comprises a chip discharging groove; the cooling part comprises an inner cooling hole. the inner cooling drill bit for improving the cooling performance; one end of the two heat conducting ports is extended to the inner wall of the drill bit; the inner wall of the heat conducting port fixedly connected with with graphene; the heat in the chip discharging groove at the drill bit is conducted to the inner cooling hole through the graphene in the heat conducting port; then cooling the graphene conductive heat by the cutting liquid, so as to solve the problem that the existing inner cooling hole cannot effectively cool the outer side of the drill bit, reducing the cooling efficiency and service life of the inner cooling drill bit, so as to improve the cooling property.