Mass reduced grinding cup

Abstract

The present invention provides a grinding cup ( 1 ) having a lower grinding section ( 2 ) and an upper body section ( 3 ) integrally connected to form a grinding cup having top ( 4 ) and bottom ( 5 ) surfaces. The grinding section ( 2 ) is formed from a material capable of grinding the hard materials such as tungsten carbide inserts of button bits etc. A centrally disposed convex recess ( 7 ) is formed in the bottom surface ( 5 ) having the desired profile for the button to be ground. One or more passageways ( 15 ) in the upper body section ( 3 ) and grinding section permit a coolant, preferably water, optionally mixed with cutting oil or a water/air mist, to be provided to the surface of the button ( 5 ) during grinding, through outlet(s) on the bottom surface. Drive means ( 8 ) are provided on or in the upper body section that cooperate with the output shaft of the grinding machine. Retaining means ( 11 ) are provided in conjunction with the drive means ( 8 ) to releasably secure the grinding cup ( 1 ) to the output shaft of the grinding machine during use.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:  
     
         1 . A grinding cup for grinding the hard metal inserts or working tips of drill bits (percussive or rotary), tunnel boring machine cutters (TBM) and raised bore machine cutters (RBM) to restore them to substantially their original profile, said grinding cups having a lower grinding section and an upper body section integrally connected to form a grinding cup having top and bottom surfaces, a centrally disposed convex recess formed in the bottom surface having the desired profile to be ground, one or more passageways in the upper body section and grinding section to permit a coolant to be provided to one or more outlets on the bottom surface, drive means provided on or in the upper body section that cooperates with the output shaft of a grinding machine, retaining means provided in conjunction with the drive means for detachable connection of the grinding cup to an output shaft of the grinding machine during use wherein the upper body section, grinding section or drive means or any combination thereof are adapted to reduce the mass of the grinding cup to reduce one or more of the factors selected from the following group (1) negative impact on operational stability, drive or contact surface area wear or damage or deformation, (2) wear or damage or deformation of elastomeric materials in drive or contact areas, or (3) other potential associated wear or damage to the grinding apparatus caused by vibration or resonance and mass associated operational loads.  
     
     
         2 . A grinding cup according to  claim 1  wherein the diameter of the body section is reduced by tapering part or all the exterior surface to form a beveled portion said beveled portion terminating in a neck portion that connects to the grinding section.  
     
     
         3 . A grinding cup according to  claim 2  wherein the reduction of the diameter of the exterior surface can be radial or form a reverse radius.  
     
     
         4 . A grinding cup according to  claim 1 ,  2  or  3  wherein the outer surface of the metal portion of said grinding section is machined to the point of connection with the upper body section in a profile substantially corresponding to the mating surface of said metal portion to the diamond matrix of said grinding section.  
     
     
         5 . A grinding cup according to  claim 1 ,  2 ,  3  or  4  wherein the diameters of the passageways through the upper body section and grinding section are as wide as possible without negatively impacting the structural integrity of the grinding cup.  
     
     
         6 . A grinding cup according to  claim 1 ,  2 ,  3 ,  4  or  5 , wherein the drive means consists of a hollow vertical upright stem centrally located on the top surface of the grinding cup.  
     
     
         7 . A grinding cup according to  claim 6  wherein cam means are provided at the base of the stem sized to engage with a diametrically extending recess at the free end of a hollow drive shaft of the grinding machine.  
     
     
         8 . A grinding cup according to  claim 7  wherein the cam means is substantially the same size as the diametrically extending recess at the free end of a hollow drive shaft of the grinding machine to optimize the contact area between the drive shaft and the grinding cup.  
     
     
         9 . A grinding cup according to  claim 1 ,  2 ,  3 ,  4  or  5 , wherein the drive means comprise a centrally disposed cavity formed in the top surface of the grinding cup, said cavity shaped and sized to permit the grinding cup to be detachably connected to the output drive shaft of the grinding machine and rotated during the grinding operation wherein an end portion of the output drive shaft is adapted to fit within the corresponding sized centrally disposed cavity and driveably engage within said cavity.  
     
     
         10 . A grinding cup according to  claim 1 ,  2 ,  3 ,  4 ,  5 ,  6 ,  7 ,  8  or  9  wherein the drive means has engagement surfaces sized and shaped to substantially match contact areas of the output drive shaft of the grinding machine.  
     
     
         11 . A grinding cup according to  claim 1 ,  6 ,  7 ,  8  or  9  wherein the drive or contact areas between the grinding cup and the output shaft of the grinding machine contain materials suitable for reducing vibration and wear or damage during operation.  
     
     
         12 . A grinding cup according to  claim 1 ,  2 ,  3 ,  4 ,  5 ,  6 ,  7 ,  8 ,  9 ,  10  or  11  wherein the mass of the grinding cup is reduced by incorporating lighter weight materials in one or more of the upper body section, the drive means or retaining means.  
     
     
         13 . A grinding cup according to  claim 12  wherein the lighter weight material incorporated to reduce the mass of the grinding cup is an elastomeric material.  
     
     
         14 . An adapter for connecting a grinding cup of one type to an output shaft of a grinding machine having a different drive system wherein the adapter is adapted to reduce the mass of the adapter to reduce one or more of the factors selected from the following group (1) negative impact on operational stability, drive or contact surface area wear or damage or deformation, (2) wear or damage or deformation of elastomeric materials in drive or contact areas, or (3) other potential associated wear or damage to the grinding apparatus caused by vibration or resonance, and mass associated operational loads.  
     
     
         15 . An adapter according to  claim 12  wherein the drive or contact areas between the grinding cup and adapter or adapter and the output shaft of the grinding machine contain materials suitable for reducing vibration and wear or damage during operation.