公开(公告)号：US20070160437A1

公开(公告)日：2007-07-12

申请号：US11564112

申请日：2006-11-28

申请人： Michael Shultz ,  Stephen George ,  Raymond Moring ,  David Ford

发明人： Michael Shultz ,  Stephen George ,  Raymond Moring ,  David Ford

IPC分类号： B23B51/00

CPC分类号： B23B51/02 ,  B23B2251/14 ,  B23B2251/18 ,  B23B2251/44 ,  Y10T408/906 ,  Y10T408/9065 ,  Y10T408/9097

摘要： The present invention is directed to a helical drill configuration that allows substantially flat bottomed holes to be machined. At the cutting end of the body member, there are at least two cutting edges that are symmetrically oriented on opposing sides of the rotational axis of the drill. In an embodiment of the invention, first and second cutting edge portions form a continuous surface which provides strength and tool stability. The height of the second portions of each of the cutting edges remains relatively consistent along the horizontal for formation of a generally flat bottom hole. In the embodiment, a center point is defined by two sloped peak surfaces. A central straight chisel edge is formed by the intersection of the two sloped peak surfaces. The first cutting edge section extends from the chisel edge to the second cutting edge section. The first cutting edge section for both cutting edges is formed by symmetrically thinning the two peak surface. In the invention, stress at the center portion of the helical cutting tool is limited by the chisel edge and first sections of the cutting edge near the center portion having a balanced geometry. The balanced geometry of the helical drill also prevents the drill from wobbling and creating deviations in the hole being formed. The chisel edge may blend with a first curvilinear cutting edge and the first curvilinear cutting edge may also have a positive rake to promote cutting.

摘要翻译： 本发明涉及一种允许基本平坦的有底孔加工的螺旋钻构型。 在主体构件的切割端处，至少有两个切削刃对称地定向在钻头的旋转轴线的相对侧上。 在本发明的一个实施例中，第一和第二切削刃部分形成一个提供强度和刀具稳定性的连续表面。 每个切削刃的第二部分的高度沿着水平线保持相对一致以形成大致平坦的底部孔。 在本实施例中，中心点由两个倾斜的峰面限定。 中心的直凿边缘由两个倾斜的峰面相交而形成。 第一切削刃部分从凿子边缘延伸到第二切削刃部分。 用于两个切削刃的第一切削刃部分通过对称地使两个峰值表面变薄而形成。 在本发明中，螺旋切削工具的中心部分处的应力受到凿子边缘和靠近中心部分具有平衡几何形状的切削刃的第一部分的限制。 螺旋钻的平衡几何形状还可防止钻头摆动并产生正在形成的孔中的偏差。 凿子边缘可以与第一曲线切割边缘混合，并且第一曲线切割边缘也可以具有正耙子以促进切割。