×

Rock drill

  • US 4,951,761 A
  • Filed: 05/31/1989
  • Issued: 08/28/1990
  • Est. Priority Date: 06/18/1988
  • Status: Expired due to Term
First Claim
Patent Images

1. A rock drill comprising a single-start or double-start conveying helix and a drilling head which has arranged on its end face pointing in the feed direction a carbide main cutting tip extending over the entire diameter of the drilling head, sloping in a roof shape and having two cutting edges, and at least one additional cutting element arranged asymmetrically relative to the cutting edges of the main cutting tip, wherein the additional cutting element is designed as a secondary cutting tip which has at least one cutting face and assumes an acute angle relative to the first cutting edge of the main cutting tip and an obtuse angle relative to the further cutting edge of the main cutting tip, and wherein the drilling head is designed in a V-shape, Y-shape or triangular shape in cross section, having at least two flat, V-shaped or concavely arched side flanks to form drilling-dust grooves.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×