Granular body grinding device, foundry sand reclamation device, and particulate generating device

A granular body grinding device comprising:

• a case for containing granular bodies;
• a drive shaft horizontally supported by the case to be rotationally drivable by a driving device;
• a single grinding disc having a disc main body that is fixed on the drive shaft and that is formed with disc surfaces perpendicular to an axial direction of the drive shaft, and formed with grinding surfaces at the disc surfaces on both sides of the disc main body so that both grinding surfaces grind the granular bodies as the granular bodies contact the grinding surfaces;
• a fluidizing device for fluidizing the granular bodies in a floating state by sending air upward from a bottom surface portion of the case, to form a fluidized bed in which at least a lower half of the grinding surfaces is on average soaked and at least a part of the grinding surfaces are on average not soaked;
• wherein the drive shaft is supported by the case to be rotationally drivable with one end side only held in a cantilever fashion;
• wherein the grinding surfaces include abrasive grains made of diamond or cubic boron nitride;
• wherein the single grinding disc is the only grinding disc fixed on the driving shaft;
• wherein the thickness of the disc main body relative to the diameter of the disc main body is 0.04 or less in ratio;
• and
• wherein the driving device is configured to rotate the drive shaft and the single grinding disc fixed to the drive shaft such that the single grinding disc rotates at a circumferential speed generating negative pressure on the grinding surfaces, the negative pressure urging the granular bodies toward the grinding surfaces so that the grinding surfaces contact and grind the granular bodies.