Abstract A cabochon gem grinding machine comprising a drum having a cylindrical wall and a lip extending inwardly from the sides of the wall for retaining a slurry of abrasive grain or grit, a pair of rollers which support and rotate the drum to distribute and maintain the slurry against the inner wall of the drum by centrifugal force, a dop for holding a gem to be ground in contact with the slurry at a desired angle to the vertical to grind a desired area of the gem, a pattern for indicating the desired shape of the gem, and a drive mechanism for rotating the gem and the pattern and for moving them toward a vertical position to grind new areas of the gem. Also, sensing and actuating apparatus is provided for detecting when a gem area has been ground to the desired size and for rotating the gem and pattern and for moving them toward vertical position to grind new areas of the gem. Also, sensing and actuating apparatus is provided for detecting when a gem area has been ground to the desired size and for rotating the gem and pattern and for moving them toward vertical position to grind new areas of the gem. A method of grinding cabochons and the like, comprising maintaining a slurry of abrasive material inside a rotating drum, holding a gem to be ground in contact with the slurry at a desired angle to the vertical to grind a desired area of the gem, rotating the gem and moving it toward the vertical when said gem area has been ground to the desired size, and repeating said steps until the gem has been ground to the desired pattern.
A cabochon gem grinding machine comprising a drum having a cylindrical wall and a lip extending inwardly from the sides of the wall for retaining a slurry of abrasive material, means mounting the drum so that its axis is horizontal and for rotating the drum to distribute and maintain the slurry against the inner wall of the drum, dop means for holding a gem to be ground in contact with the slurry at a desired angle to the vertical to grind a desired area of the gem, and pattern means connected to the dop means for indicating the desired shape of the gem.
Claim 2
Dependent Claim
103 words
A cabochon gem grinding machine comprising a drum having a cylindrical wall and a lip extending inwardly from the sides of the wall for retaining a slurry of abrasive material, means mounting the drum so that its axis is horizontal and for rotating the drum to distribute and maintain the slurry against the inner wall of the drum, dop means for holding a gem to be ground in contact with the slurry at a desired angle to the vertical to grind a desired area of the gem, and pattern means connected to the dop means for indicating the desired shape of the gem.
Claim 3
Dependent Claim
31 words
The gem grinder of claim 1 including means for rotating the gem and the pattern means and for moving them toward a vertical position to grind new areas of the gem.
Claim 4
Dependent Claim
43 words
The gem grinder of claim 1, wherein said means for rotating the drum includes a drive roller and an idler roller which support the drum and rotate it, whereby said drum is easily removed for cleaning and easily replaced by other similar drums.
Claim 5
Dependent Claim
24 words
The gem grinder of claim 1, including sensing means for detecting when the gem area being ground has been ground to the desired pattern.
Claim 6
Dependent Claim
40 words
The gem grinder of claim 4 including actuating means responsive to the sensing means for rotating the axes of the pattern means and gem and for moving said axis toward the vertical to present another gem area to be ground.