Diamond core drill bit

• US 7,204,244 B1
• Filed: 03/02/2006
• Issued: 04/17/2007
• Est. Priority Date: 03/02/2006
• Status: Active Grant

• Current Assignee: Luminare Supply Corporation
• Original Assignee: Luminare Supply Corporation
• Inventors: Pedersen, Lyle Dean
• Primary Examiner(s): Rose; Robert A.
• Application Number:
  US11/307,998
• Time in Patent Office: 411 Days
• Field of Search: 451/548, 451/541, 451/550, 125/20
• US Class Current: 125/20
• CPC Class Codes: B28D 1/041 with cylinder saws, e.g. trepanning; saw cylinders, e.g. having their cutting rim equipped with abrasive particles

Abstract

A diamond core drill bit (100) is disclosed. The drill bit has a right-circular cylindrical body (120) with at least one side lubrication hole (122) toward the bottom of the body and a plurality of parallel grooves (124) oriented in an axial direction at the bottom circumferential sidewall of the body. A cap (130) at the top of the cylindrical body (120) closes one end of the body. The cap has a central lubrication hole (134) and alternative embodiments have at least one core extraction hole (132). These holes extend through the cap to the interior of the body. A hollow drive shaft (140) is mated to the cap (130) over the central lubrication hole (134), such that a lubricant can flow through the hollow shaft and into the internal volume of the body and out a side lubrication hole (122). Diamond grit (160) is bonded around the bottom edge on a portion of the internal and external sidewall surfaces at the bottom circumferential edge of the body (120) in such a way that the diamond grit (160) is bonded over a portion of the axial height of the grooves (124).

Claims

1. A diamond core drill bit comprising,

a nickel-plated body in the form of a right-circular cylinder and having a plurality of grooves creating an uneven, wave-like bonding surface, said grooves being parallel to each other and axial in height extending from at least one bottom circumferential sidewall of the body;

diamond grit bonded around the bottom circumferential edge of the body on a portion of the internal and external sidewalls wherein the diamond grit is bonded over a portion of the axial height of the grooves so as to create multi-directional bonding forces between the diamonds and the bonding surface;

a nickel-plated cap at the top of the body having a central lubrication hole; and

,

a nickel-plated hollow shaft mated to the cap over the central lubrication hole wherein a lubricant can flow through the hollow shaft and into the internal volume of the body and out the side lubrication hole.

2. The diamond core drill bit of claim 1 wherein the body has a drilling diameter of about three inches or less.

3. The diamond core drill bit of claim 1 wherein the axial height of the grooves is about three eights of an inch in height.

4. The diamond core drill bit of claim 1 wherein the body has at least one side lubrication hole toward the bottom of the body.

5. The diamond core drill bit of claim 1 wherein the cap has at least one core extraction hole.

6. The diamond core drill bit of claim 1 wherein the cap has three core extraction holes.

7. The diamond core drill bit of claim 1 wherein the hollow shaft is three-eighths inches or less in outside diameter.

8. The diamond core drill bit of claim 1 wherein the hollow shaft is one-half inches or less in outside diameter.

9. The diamond core drill bit of claim 1 wherein the body has a wall thickness of about one-half millimeter.

10. The diamond core drill bit of claim 1 wherein the diamond grit is bonded by an electro-plating process.

11. The diamond core drill bit of claim 1 wherein the diamond grit is bonded by a hardened synthetic resin.

12. The diamond core drill bit of claim 1 wherein the diamond grit is about four tenths of a millimeter or less in thickness and rises about three-sixteenths of an inch from the bottom edge on both the inside and outside wall of the body.