Rolling cutter

Abstract

A cutting element for a drill bit includes an outer support element and an inner rotatable cutting element, a portion of which is disposed in the outer support element, where the inner rotatable cutting element has a body with a non-planar cutting face.

What is claimed is: 
     
       1. A cutting element for a drill bit, comprising:
 an outer support element; and 
 an inner rotatable cutting element, a portion of which is disposed in the outer support element, the inner rotatable cutting element comprising:
 a body having a non-planar cutting face; 
 wherein the body comprises an a single ultra hard material body disposed on an interface surface of a substrate, the ultra hard material body forming the non-planar cutting face; and 
 wherein a radial bearing is formed between a portion of the ultra hard material body and the outer support element. 
 
 
     
     
       2. The cutting element of  claim 1 , wherein the ultra hard material body comprises diamond. 
     
     
       3. The cutting element of  claim 1 , wherein the outer support element covers a portion of the non-planar cutting face. 
     
     
       4. A cutting element for a drill bit, comprising:
 an outer support element; 
 an inner rotatable cutting element, a portion of which is disposed in the outer support element, the inner rotatable cutting element comprising:
 a non-planar cutting face; 
 a body comprising a shaft portion, the shaft portion having a diameter less than the diameter of the non-planar cutting face; and 
 
 an axial bearing formed between a portion of the outer support element and the inner rotatable cutting element. 
 
     
     
       5. The cutting element of  claim 4 , wherein the non-planar cutting face comprises a plurality of surface alterations formed thereon. 
     
     
       6. The cutting structure of  claim 5 , wherein the surface alterations have a depth ranging from 0.001 to 0.05 inches. 
     
     
       7. The cutting element of  claim 4 , wherein the non-planar cutting face is dome shaped, the dome shape extending across the diameter of the non-planar cutting face. 
     
     
       8. The cutting element of  claim 4 , wherein the non-planar cutting face has a convex shape. 
     
     
       9. The cutting element of  claim 4 , wherein the cutting element further comprises at least one retention mechanism disposed between the inner rotatable cutting element and the outer support element. 
     
     
       10. A drill bit, comprising:
 a bit body having a plurality of blades extending radially from the bit body and axially along a length of the bit body; and 
 at least one cutting element of  claim 4  mounted to at least one of the plurality of blades. 
 
     
     
       11. The cutting element of  claim 4 , wherein the non-planar cutting face is saddle shaped. 
     
     
       12. A cutting structure for a cutting tool, comprising:
 an outer support element having a bottom portion and a side portion; and 
 an inner rotatable cutting element, a portion of which is disposed in the outer support element; 
 wherein the outer support element further comprises an inner shaft portion extending from the bottom portion into the inner rotatable cutting element. 
 
     
     
       13. The cutting structure of  claim 12 , wherein the inner shaft portion is threadedly attached to the bottom portion. 
     
     
       14. The cutting structure of  claim 12 , wherein the inner shaft portion is integral with the bottom portion. 
     
     
       15. The cutting structure of  claim 12 , wherein an upper end of the inner shaft portion extends partially over a cutting face of the inner rotatable cutting element. 
     
     
       16. The cutting structure of  claim 12 , wherein at least a portion of a bearing surface of the outer support element comprises a lubricious material. 
     
     
       17. The cutting structure of  claim 12 , wherein the outer support element is integral with a cutting tool body. 
     
     
       18. The cutting structure of  claim 12 , wherein at least a side portion of the outer support element is a blade of a cutting tool. 
     
     
       19. The cutting structure of  claim 12 , wherein the outer support element is a discrete element. 
     
     
       20. A drill bit, comprising:
 a bit body having a plurality of blades extending radially therefrom; and 
 at least one cutting element of  claim 12  mounted to at least one of the plurality of blades. 
 
     
     
       21. A structure of a cutting tool, comprising:
 an outer support element; and   an inner rotatable element at least partially within the outer support element, the inner rotatable element including opposing ends that each comprise an ultra hard material portion.   
     
     
       22. The structure of claim 21, the inner rotatable element further including at least one substrate portion between the ultra hard material portions of the opposing ends of the inner rotatable element. 
     
     
       23. The structure of claim 21, wherein the inner rotatable element includes a side surface extending between the ultra hard material portions of the opposing ends, and wherein at least a portion of the side surface of the inner rotatable element includes an ultra hard material. 
     
     
       24. The structure of claim 23, wherein the ultra hard material of the side surface is distinct from the ultra hard material portions of the opposing ends of the inner rotatable element. 
     
     
       25. The structure of claim 23, wherein the ultra hard material of the side surface is on a circumferential bearing surface. 
     
     
       26. The structure of claim 23, wherein the ultra hard material of the side surface forms a continuous circumferential bearing surface around the inner rotatable element. 
     
     
       27. The structure of claim 23, wherein the ultra hard material of the side surface includes discrete ultra hard segments positioned a circumference of the inner rotatable element. 
     
     
       28. The structure of claim 23, wherein the ultra hard material of the side surface is in an ultra hard material layer extending a full diameter of the inner rotatable element. 
     
     
       29. The structure of claim 21, wherein the outer support element is integral with and defined by a cutting tool. 
     
     
       30. The structure of claim 21, wherein the outer support element comprises at least a first portion that covers a portion of a side surface of the inner rotatable element and a second portion that covers at least a portion of a first end of the opposing ends of the inner rotatable element. 
     
     
       31. The structure of claim 21, wherein the outer support element covers at least a portion of each of the opposing ends of the inner rotatable element, and the outer support element extends a full length of the inner rotatable element and covers a full length of a portion of a side surface of the inner rotatable element. 
     
     
       32. The structure of claim 31, wherein a portion of the side surface and at least a portion of one of the opposing ends are exposed while the inner rotatable element is within the outer support element. 
     
     
       33. The structure of claim 21, wherein the inner rotatable element is a cylindrical body having a substantially constant diameter along its entire length. 
     
     
       34. A cutting tool, comprising:
 a tool body, the tool body including at least one radially extending blade; and   at least one pocket formed in the at least one blade,   at least one rolling element retained in the at least one pocket such that the at least one rolling element is free to rotate about an axis of the at least one rolling element, the at least one rolling element including opposing end faces and ultra hard material at each of the opposing end faces.   
     
     
       35. The cutting tool of claim 34, wherein the at least one rolling element includes a side surface between ultra hard material portions at the opposing end faces, and wherein at least a portion of the side surface of the inner rotatable element comprises an ultra hard material on an outer circumference of the side surface. 
     
     
       36. The cutting tool of claim 34, wherein the ultra hard material of the side surface of the inner rotatable element is on a bearing surface and either forms an ultra hard material layer or is embedded within a substrate of the at least one rolling element. 
     
     
       37. The cutting tool of claim 34, wherein the at least one rolling element is a rotatable cutting element. 
     
     
       38. A structure of a cutting tool, comprising:
 an outer support element; and   an inner rotatable element, a portion of which is disposed in the outer support element, wherein a first portion of the outer support element covers a portion of a first end surface of the inner rotatable element, wherein a second portion covers at least a portion of a second end surface of the inner rotatable element, and wherein a side portion of the outer support element extending between the first and second portions of the outer support element covers a portion of a side surface of the inner rotatable element extending between the first and second ends of the inner rotatable element.   
     
     
       39. The structure of claim 38, wherein the inner rotatable element comprises a plurality of distinct layers of diamond. 
     
     
       40. The structure of claim 39, wherein the plurality of distinct layers include distinct layers at each of the first and second end surfaces of the inner rotatable element. 
     
     
       41. The structure of claim 40, wherein the plurality of distinct layers include at least one intermediate layer between the distinct layers at each of the first and second end surfaces of the inner rotatable element. 
     
     
       42. The structure of claim 38, wherein the outer support element includes a blade of a drill bit. 
     
     
       43. The structure of claim 38, wherein the outer support element includes at least one bearing surface opposite the inner rotatable element. 
     
     
       44. An element of a drill bit, comprising:
 an outer support element; and   an inner rotatable element, a portion of which is encased by the outer support element, the inner rotatable element including first and second end surfaces and a side surface extending between the first and second end surfaces, at least the first end surface including a diamond face,   wherein the outer support element comprises a first portion that at least partially covers the diamond face and a second portion that partially covers the side surface of the inner rotatable element, wherein the first portion and the second portion of the outer support element are integral.   
     
     
       45. The element of claim 44, wherein the inner rotatable element is in a pocket in a blade of the drill bit, and wherein the outer support element is the blade. 
     
     
       46. The element of claim 44, wherein at least a portion of the side surface of the inner rotatable element is exposed. 
     
     
       47. The element of claim 44, wherein the outer support element further comprises a third portion that at least partially covers the second end surface of the inner rotatable element. 
     
     
       48. A drill bit, comprising:
 a bit body having at least one radially extending blade;   at least one pocket formed in the at least one radially extending blade, and   at least one rolling element having a cylindrical body with a substantially constant diameter along its entire length retained in the at least one pocket, such that the at least one rolling element is free to rotate about an axis of the rolling element.   
     
     
       49. The drill bit of claim 48, wherein the at least one rolling element includes first and second ends of the cylindrical body and at least first and second diamond portions, wherein the first diamond portion is closer to the first end of the cylindrical body than to the second end of the cylindrical body, and wherein the second end of the cylindrical body is closer to the second diamond portion than to the first diamond portion. 
     
     
       50. The drill bit of claim 49, wherein the at least one rolling element includes a third diamond portion axially between the first and second diamond portions, and wherein the third diamond portion is at least partially on a circumferential side surface of the cylindrical body of the at least one rolling element. 
     
     
       51. The drill bit of claim 50, wherein the third diamond portion forms a continuous bearing surface around the circumferential side surface of the cylindrical body. 
     
     
       52. The drill bit of claim 48, wherein the cylindrical body includes opposing ends and the at least one rolling element comprises diamond at each of the opposing ends of the cylindrical body. 
     
     
       53. The drill bit of claim 48, wherein the at least one radially extending blade defines is integral with, and defines, an outer support element partially enclosing the at least one rolling element. 
     
     
       54. The drill bit of claim 48, wherein the at least one rolling element is a rolling cutting element.