Seal for an earth bit

Abstract

An earth bit includes a cutting cone rotatably mounted to a lug with a hub unit. A sealing member is positioned to provide a seal between the cutting cone and lug. The sealing member includes an O-ring core enclosed by a sleeve having a seam extending annularly around it. The seam restricts the rotation of the sleeve around the O-ring core.

1 . An earth bit, comprising:
 a cutting cone rotatably mounted to a lug with a hub unit; and   a sealing member positioned to provide a seal between the cutting cone and lug and/or hub unit, the sealing member including an O-ring core enclosed by a sleeve having a first seam extending around it.   
   
   
       2 . The earth bit of  claim 1 , wherein the first seam engages a static sealing surface. 
   
   
       3 . The earth bit of  claim 1 , further including a second seam which engages a static sealing surface. 
   
   
       4 . The earth bit of  claim 3 , wherein the first and second seams extend along inner and outer portions of the O-ring core. 
   
   
       5 . The earth bit of  claim 1 , further wherein the first seam restricts the rotation of the sleeve about the O-ring core in response to engaging the cutting cone, hub unit and/or lug. 
   
   
       6 . The earth bit of  claim 1 , wherein the sleeve is slidingly engaged with the O-ring core. 
   
   
       7 . An earth bit, comprising:
 a cutting cone rotatably mounted to a lug with a hub unit; and   a sealing member positioned to provide a seal between the cutting cone and lug and/or hub unit, the sealing member including an O-ring core enclosed by a sleeve having first and second seams extending around it.   
   
   
       8 . The earth bit of  claim 7 , wherein the first seam faces the hub unit and the second seam faces away from the hub unit. 
   
   
       9 . The earth bit of  claim 7 , wherein the first and second seams oppose each other. 
   
   
       10 . The earth bit of  claim 7 , wherein the sleeve includes first and second sleeve pieces coupled together by the first and second seams. 
   
   
       11 . The earth bit of  claim 7 , wherein the sleeve includes wear resistant material with opposed ends seamed together. 
   
   
       12 . The earth bit of  claim 7 , wherein the first and second seams extend annularly around the O-ring core. 
   
   
       13 . A method of assembling an earth bit, comprising:
 providing a lug which carries a hub unit;   providing a sealing member which includes an O-ring core and a sleeve, wherein the sleeve includes a first seam extending around the O-ring core; and   rotatably mounting a cutting cone to the hub unit so the sealing member forms a seal between the cutting cone and hub unit.   
   
   
       14 . The method of  claim 13 , wherein the sleeve further includes a second seam extending around the O-ring core. 
   
   
       15 . The method of  claim 14 , wherein the first and second seams oppose each other. 
   
   
       16 . The method of  claim 14 , further including positioning the sealing member so the first seam faces the hub unit and the second seam faces away from the hub unit. 
   
   
       17 . The method of  claim 14 , wherein the sleeve includes a third seam which extends at a non-zero angle relative to the first and second seams. 
   
   
       18 . The method of  claim 13 , further enclosing the O-ring core with the sleeve. 
   
   
       19 . The method of  claim 13 , further including forming the sleeve by coupling first and second sleeve pieces together. 
   
   
       20 . The method of  claim 13 , further including wrapping the sleeve around the O-ring core and seaming its opposed sides together.