Robert Boschgmbh

Helmut Duscha

August Haussmann

Rainer Widmann

Massimo Anghileri

Hans-Peter Fuessl

Peter Keller-Sornig

Wolfgang Rieger

Michalis Stefanopulos

Peter Schwaller

Wilhelm Eckert

Harry Fluhr

Andreas Schlachter

The invention relates to a rock drill () for rotational and percussive action, comprising a drill head (), a conveying helix (), a clamping shank and a longitudinal drill axis (L), wherein the drill head () has at least one secondary cutting element () with a front and a rear side face () and wherein the secondary cutting element () has a center of mass (M) and a cutting edge (), the center of mass (M) and the cutting edge () defining a first plane (E), the front side face () of the secondary cutting element () defining a second plane (E) and the rear side face () of the secondary cutting element () defining a third plane (E). In this arrangement, the longitudinal drill axis (L) intersects the first plane (E) at a first point of intersection (S), the longitudinal drill axis (L) intersects the second plane (E) and/or the third plane (E) at a second and/or third point of intersection (S, S), the longitudinal drill axis (L) and the first plane (E) form a first acute angle () in the direction of advancement (x) of the rock drill () and the longitudinal drill axis (L) and the second and/or third plane (E, E) form a second and/or third acute angle () in the direction of advancement (x) of the rock drill ().

Rock drill

The present invention relates to a multi-purpose drilling tool with a boring head, a drill twist connected thereto and a downstream clamping shank, a cutting element () being provided on the working side of the boring head. The cutting element () has a face () with a rake angle (&#x3b3;) having a value of &#x3b3;&#x2267;0&#xb0; b, the cutting element () having a flank () with a lip clearance angle (&#x3b1;) having a value of 5&#xb0;&#x2266;&#x3b1;&#x2266;15&#xb0; and, in particular, &#x3b1;&#x2248;10&#xb0;.

Multi-purpose drilling tool

Rotary impact drill bit

Growing community of inventors

Ravensburg, Germany

Helmut Duscha