公开(公告)号：US10328499B2

公开(公告)日：2019-06-25

申请号：US15605466

申请日：2017-05-25

Applicant: IRWIN INDUSTRIAL TOOL COMPANY

Inventor： LaVerne R. Durfee

IPC: B23B51/02 ,  B23B51/00

Abstract: A step drill bit has a cutting head defining a longitudinal axis and having a plurality of steps having different effective diameters. First and second cutting edges are formed in the cutting head. The first cutting edge and the second cutting edge are arranged such that the bit is asymmetric in a plane perpendicular to the longitudinal axis relative to a plane containing the longitudinal axis. A rubbing surface is formed on each step where the rubbing surface extends to approximately the effective diameter of that step such that the first cutting edge, second cutting edge and the rubbing surface forms three points of contact with the side wall of the hole being cut.

公开(公告)号：US20170129022A1

公开(公告)日：2017-05-11

申请号：US15341506

申请日：2016-11-02

Applicant: IRWIN INDUSTRIAL TOOL COMPANY

Inventor： LaVerne R. Durfee

IPC: B23B51/00

CPC classification number: B23B51/009 ,  B23B2251/046 ,  B23B2251/282 ,  B23B2251/408 ,  Y10T408/906

Abstract: A step drill bit can include a cutting head defining a longitudinal axis and multiple steps having different effective diameters. First and second cutting edges can be formed in the cutting head. The first cutting edge and the second cutting edge can be arranged such that the bit is asymmetric in a plane perpendicular to the longitudinal axis relative to a plane containing the longitudinal axis. The step drill bit can further include one or more flutes. Each flute can define a groove in the cutting head that extends along a helical path about the longitudinal axis. Each flute can have a variable helix angle such that the angle of the helix about the longitudinal axis changes at one or more points along the length of the flute.

公开(公告)号：US20140369776A1

公开(公告)日：2014-12-18

申请号：US14299163

申请日：2014-06-09

Applicant: IRWIN INDUSTRIAL TOOL COMPANY

Inventor： LaVerne R. Durfee

IPC: B23B51/00

CPC classification number: B23B51/009 ,  B23B2251/282 ,  B23B2251/70 ,  Y10T408/906

Abstract: A step drill bit has a cutting head defining a longitudinal axis and having a plurality of steps having different effective diameters. First and second cutting edges are formed in the cutting head. The first cutting edge and the second cutting edge are arranged such that the bit is asymmetric in a plane perpendicular to the longitudinal axis relative to a plane containing the longitudinal axis. A rubbing surface is formed on each step where the rubbing surface extends to approximately the effective diameter of that step such that the first cutting edge, second cutting edge and the rubbing surface forms three points of contact with the side wall of the hole being cut.

Abstract translation: 步进钻头具有限定纵向轴线并具有不同有效直径的多个台阶的切割头。 在切割头中形成有第一和第二切削刃。 第一切削刃和第二切削刃被布置成使得钻头在垂直于纵向轴线的平面中相对于包含纵向轴线的平面是不对称的。 摩擦表面形成在摩擦表面延伸到该步骤的大致有效直径的每个步骤上，使得第一切削刃，第二切削刃和摩擦表面与被切削的孔的侧壁形成三个接触点。

公开(公告)号：US20170259350A1

公开(公告)日：2017-09-14

申请号：US15605466

申请日：2017-05-25

Applicant: IRWIN INDUSTRIAL TOOL COMPANY

Inventor： LaVerne R. Durfee

IPC: B23B51/00

CPC classification number: B23B51/009 ,  B23B2251/282 ,  B23B2251/70 ,  Y10T408/906

Abstract: A step drill bit has a cutting head defining a longitudinal axis and having a plurality of steps having different effective diameters. First and second cutting edges are formed in the cutting head. The first cutting edge and the second cutting edge are arranged such that the bit is asymmetric in a plane perpendicular to the longitudinal axis relative to a plane containing the longitudinal axis. A rubbing surface is formed on each step where the rubbing surface extends to approximately the effective diameter of that step such that the first cutting edge, second cutting edge and the rubbing surface forms three points of contact with the side wall of the hole being cut.

公开(公告)号：US09687915B2

公开(公告)日：2017-06-27

申请号：US14299163

申请日：2014-06-09

Applicant: Irwin Industrial Tool Company

Inventor： LaVerne R. Durfee

IPC: B23B51/00

CPC classification number: B23B51/009 ,  B23B2251/282 ,  B23B2251/70 ,  Y10T408/906

Abstract: A step drill bit has a cutting head defining a longitudinal axis and having a plurality of steps having different effective diameters. First and second cutting edges are formed in the cutting head. The first cutting edge and the second cutting edge are arranged such that the bit is asymmetric in a plane perpendicular to the longitudinal axis relative to a plane containing the longitudinal axis. A rubbing surface is formed on each step where the rubbing surface extends to approximately the effective diameter of that step such that the first cutting edge, second cutting edge and the rubbing surface forms three points of contact with the side wall of the hole being cut.