Bit Sleeve with Compression Band Retainers

Abstract

A bit sleeve for holding a tool bit in a block having a bore that is at least partially tapered, including a collar having a front face for supporting a flange on the tool bit, a flange located rearward of the collar and having a diameter larger than that of the collar, a shank located rearward of the flange and having a diameter smaller than that of the flange, a body adapted to be received into the bore of the block and having a front spherically-shaped portion joined to a rear straight cylindrical portion, a front compression band mounted in a groove in the front portion, and a rear compression band mounted in a groove in the rear portion, wherein when the bit sleeve is installed in the bore, the first and second compression bands are compressed between the body and the bore to secure the sleeve within the bore.

1 . A bit sleeve for holding a tool bit in a block having a bore that is at least partially tapered, the bit sleeve comprising:
 a collar having a front face for supporting a flange on the tool bit;   a flange located rearward of the collar, the flange having a diameter larger than that of the collar;   a shank located rearward of the flange, the shank having a diameter smaller than that of the flange;   a body adapted to be received into the bore of the block, the body having a front portion joined to a rear portion;   a first groove in the front portion of the body configured to receive a first compression band; and   a second groove in the rear portion of the body configured to receive a second compression band,   wherein, when the bit sleeve is installed in the bore of the block, the first compression band is located entirely within the bore with a front edge of the first compression band in alignment with a front face of the block and the second compression band is located entirely within the bore with a rear edge of the second compression band in alignment with a rear face of the block.   
     
     
         2 . The bit sleeve of  claim 1 , wherein a front portion of the bore has a tapered wall and wherein the front portion of the body has a spherically-curved wall. 
     
     
         3 . The bit sleeve of  claim 2 , wherein a rear portion of the bore has a straight cylindrical wall and wherein the rear portion of the body has a straight cylindrical wall. 
     
     
         4 . The bit sleeve of  claim 1 , further comprising:
 a shoulder extending rearwardly from the flange, the shoulder having a pair of rearwardly oriented corners substantially aligned with the centerline of the bit sleeve, the corners being configured to be contacted by a wedge-shaped removal tool.   
     
     
         5 . The bit sleeve of  claim 1 , wherein the flange includes a flat lateral face configured to engage a flat lateral surface on the block to prevent rotation of the bit sleeve within the bore. 
     
     
         6 . A bit sleeve for holding a tool bit in a block having a bore that is at least partially tapered, the bit sleeve comprising:
 a collar having a front face for supporting a flange on the tool bit;   a flange located rearward of the collar, the flange having a diameter larger than that of the collar;   a shank located rearward of the flange, the shank having a diameter smaller than that of the flange;   a body adapted to be received into the bore of the block, the body having a front spherically-curved portion joined to a rear straight cylindrical portion;   a first compression band mounted in a groove in the front portion of the body; and   a second compression band mounted in a groove in the rear portion of the body;   wherein, when the bit sleeve is installed in the bore of the block, the first and second compression bands are compressed between the body and the bore to secure the bit sleeve within the bore, the first compression band is located entirely within the bore with a front edge of the first compression band in alignment with a front face of the block, and the second compression band is located entirely within the bore with a rear edge of the second compression band in alignment with a rear face of the block.   
     
     
         7 . A bit sleeve for holding a tool bit in a block having a bore that is at least partially tapered, the bit sleeve comprising:
 a collar having a front face for supporting a flange on the tool bit;   a flange located rearward of the collar, the flange having a diameter larger than that of the collar;   a shoulder extending rearwardly from the flange and having a pair of rearwardly oriented corners substantially aligned with the centerline of the bit sleeve;   a shank located rearward of the flange, the shank having a diameter smaller than that of the flange; and   a body adapted to be received into the bore of the block;   wherein the corners of the shoulder are configured to be contacted by a wedge-shaped removal tool, and   wherein, when the bit sleeve is installed in the bore of the block, the first compression band is located entirely within the bore with a front edge of the first compression band in alignment with a front face of the block and the second compression band is located entirely within the bore with a rear edge of the second compression band in alignment with a rear face of the block.   
     
     
         8 . A mining machine, comprising:
 a rotatable member; and   one or more blocks mounted on the rotatable member, each block including a bit sleeve installed in a block having a bore that is at least partially tapered;   wherein the bit sleeve includes:   a collar having a front face for supporting a flange on the tool bit;   a flange located rearward of the collar, the flange having a diameter larger than that of the collar;   a shank located rearward of the flange, the shank having a diameter smaller than that of the flange;   a body adapted to be received into the bore of the block, the body having a front portion joined to a rear portion;   a first compression band mounted in a groove in the front portion of the body; and   a second compression band mounted in a groove in the rear portion of the body;   wherein the first and second compression bands are compressed between the body and the bore to secure the bit sleeve within the bore, and   wherein, when the bit sleeve is installed in the bore of the block, the first compression band is located entirely within the bore with a front edge of the first compression band in alignment with a front face of the block and the second compression band is located entirely within the bore with a rear edge of the second compression band in alignment with a rear face of the block.   
     
     
         9 . The bit sleeve of  claim 1 , wherein, when the bit sleeve is installed in the bore with the first and second compression bands seated in the bore, a gap exists between the front face of the block and the shoulder. 
     
     
         10 . The bit sleeve of  claim 1 , wherein the groove in the front portion has a first length in the axial direction of the bit sleeve, the groove in the rear portion has a second length, and the second length is larger than the first length. 
     
     
         11 . The bit sleeve of  claim 10 , wherein the second length is about twice as large as the first length. 
     
     
         12 . The bit sleeve of  claim 1 , wherein the second compression band has a planar outer peripheral surface. 
     
     
         13 . The bit sleeve of  claim 1 , wherein, when the bit sleeve is installed in the bore of the block, the first compression band seals the front end of an annular space between the body and the bore, and the second compression band seals the rear end of the annular space. 
     
     
         14 . The bit sleeve of  claim 13 , wherein the seals formed by the first compression band and the second compression band substantially prevents moisture and debris from entering the annular space. 
     
     
         15 . The bit sleeve of  claim 1 , wherein the first compression band and the second compression band are made from a resilient abrasion-resistant material. 
     
     
         16 . The bit sleeve of  claim 15 , wherein the resilient abrasion-resistant is a nylon composite material. 
     
     
         17 . The bit sleeve of  claim 1 , wherein the first compression band and the second compression band are made from a nylon composite material including glass in the composite. 
     
     
         18 . The bit sleeve of  claim 17 , wherein the nylon composite material includes about 10% to about 50% glass. 
     
     
         19 . A combination comprising:
 a block having a bore that is at least partially tapered; and   a bit sleeve for holding a tool bit in the block,   wherein the bit sleeve includes:   a collar having a front face for supporting a flange on the tool bit;   a flange located rearward of the collar, the flange having a diameter larger than that of the collar;   a shank located rearward of the flange, the shank having a diameter smaller than that of the flange;   a body adapted to be received into the bore of the block, the body having a front portion joined to a rear portion;   a first groove in the front portion of the body configured to receive a first compression band; and   a second groove in the rear portion of the body configured to receive a second compression band, and   wherein, when the bit sleeve is installed in the bore of the block, the first compression band is located entirely within the bore with a front edge of the first compression band in alignment with a front face of the block and the second compression band is located entirely within the bore with a rear edge of the second compression band in alignment with a rear face of the block.   
     
     
         20 . The combination of  claim 19 , wherein, when the bit sleeve is installed in the bore of the block, the first compression band seals the front end of an annular space between the body and the bore, and the second compression band seals the rear end of the annular space. 
     
     
         21 . The combination of  claim 20 , wherein the seals formed by the first compression band and the second compression band substantially prevents moisture and debris from entering the annular space. 
     
     
         22 . The combination of  claim 19 , wherein the first compression band and the second compression band are made from a nylon composite material including glass in the composite.