Rotary air percussion bit

摘要

A rotary air percussion bit has a cylindrically shaped sidewall, a body portion with a flat or recessed face on one end and a shank attached to the remaining end. A plurality of inserts of wear resistant material is mounted in the face and extending outwardly therefrom. A plurality of chip cutting grooves is formed in the face and extending radially from the axis of the body outwardly to the sidewalls. In order to improve the chip removal from the bit a plurality of chip clearance grooves is formed in the sidewall of the body extending from the terminus of the face chip cutting grooves and spiraling from the face to the shank end. The angle of the spiral with respect to the face is less than 45 DEG .