Lapidary machine
OwnerBradford J. Wheelerinventor
Life of this patent
Estimating the term…
Abstract
A lapidary machine having a fluid-actuated chuck arranged for facilitating insertion into and removal from the chuck of a dopstick provided with a shank of substantially square cross section. By this arrangement, dopsticks can be easily changed and quickly indexed relative to the associated guide in order to decrease set-up time of the machine while assuring proper orientation of a gemstone with respect to the guide. The machine is also provided with a dashpot connected to the frame of the device and to the chuck, which is mounted for swinging movement of the frame, for preventing rapid movement of the chuck relative to an associated grinding wheel which could damage a stone being profiled.
Claims7
A fluid-actuated chuck, comprising, in combination:
- (a) a collet provided with a square hole for receiving a dopstick having a mating square shaft;
- (b) a nose cap having front and rear openings and a through passage extending between the openings, the passage decreasing in diameter toward the front of the openings, with the collet being slidably disposed within the passage of the nose cap;
- (c) a push rod connected to the collet and extending away from the rear of the opening of the nose cap, a cylinder connected to a source of fluid under pressure and connected to the nose cap, a piston connected to the push rod and normally biased away from the nose cap, the fluid under pressure moving the piston toward the nose cap and moving the collet toward the front of the openings of the nose cap, the collet being provided with a tapered nose including means for increasing the resiliency of the tapered nose and being matably received in the decreasing diameter portion of the passage of the nose cap in order to be clamped against the dopstick and retain the dopstick in the hole provided in the collet;
- (d) a hub attached to the cylinder and extending longitudinally away from the collet and nose cap, the hub having a square cross section;
- and
- (e) a stone guide provided with a square hole mating with the hub, the stone guide being removably mounted on the hub, with a consistent orientation thus being assured between the stone guide and dopstick.
In a lapidary machine including a supporting frame, a grinding wheel assembly and a guide wheel assembly both mounted on the frame, and a chuck assembly mounted on the frame for movement relative to the frame and the grinding wheel and guide wheel assemblies, the improvement wherein the chuck assembly includes a fluid-actuated chuck for retaining a dopstick in the chuck assembly, the fluid-actuated chuck, comprising, in combination:
- (a) a collet provided with a square hole for receiving a dopstick having a mating square shaft;
- (b) a nose cap having front and rear openings and a through passage extending between the openings, the passage decreasing in diameter toward the front of the openings, with the collet being slidably disposed within the passage of the nose cap for clamping against the dopstick;
- (c) a push rod connected to the collet and extending away from the rear of the opening of the nose cap, a cylinder connected to a source of fluid under pressure and connected to the nose cap, a piston connected to the push rod and normally biased away from the nose cap, the fluid under pressure moving the piston toward the nose cap and moving the collet toward the front of the openings of the nose cap;
- (d) a hub attached to the cylinder and extending longitudinally away from the collet and nose cap, the hub having a square cross section;
- and
- (e) a stone guide provided with a square hole mating with the hub, the stone guide being removably mounted on the hub, with a consistent orientation thus being assured between the stone guide and dopstick.
Dependencies are inferred from the claim text.