A cutting machine can include a cutting machine body that is movably supported above a table and capable of vertical movement, the cutting machine body can be positioned at an upward waiting position and a lower end position. The cutting machine body can include an auxiliary cover positioned around a portion of a blade and including a projection. When in the upward waiting position the auxiliary cover is not able to move upward because of the position of the projection, and in the lower end position the auxiliary cover is able to move upward.

Semiconductor wafers are produced from a workpiece by means of a wire saw, by feeding the workpiece through an arrangement of wires tensioned between wire guide rollers and divided into wire groups, the wires moving in a running direction producing kerfs as wires engage the workpiece. For each of the wire groups, a placement error of the kerfs of the wire groups determined, and for each of the wire groups compensating movements of the wires of the wire group are induced as a function of the placement error, in a direction perpendicular to the running direction of the wires during feeding of the workpiece through the arrangement of wires, by activating at least one drive element.

Semiconductor wafers are produced from a workpiece by means of a wire saw, by feeding the workpiece through an arrangement of wires tensioned between wire guide rollers and divided into wire groups, the wires moving in a running direction producing kerfs as wires engage the workpiece. For each of the wire groups, a placement error of the kerfs of the wire groups determined, and for each of the wire groups compensating movements of the wires of the wire group are induced as a function of the placement error, in a direction perpendicular to the running direction of the wires during feeding of the workpiece through the arrangement of wires, by activating at least one drive element.

Semiconductor wafers with improved geometry are produced from a workpiece by processing the workpiece by means of a wire saw, by feeding the workpiece through an arrangement of wires which are tensioned between wire guide rollers and move in a running direction; producing kerfs when the wires engage into the workpiece; determining a placement error of the kerfs; and inducing a compensating movement of the workpiece as a function of the determined placement error along a longitudinal axis of the workpiece during the feeding of the workpiece through the arrangement of wires.

Semiconductor wafers with improved geometry are produced from a workpiece by processing the workpiece by means of a wire saw, by feeding the workpiece through an arrangement of wires which are tensioned between wire guide rollers and move in a running direction; producing kerfs when the wires engage into the workpiece; determining a placement error of the kerfs; and inducing a compensating movement of the workpiece as a function of the determined placement error along a longitudinal axis of the workpiece during the feeding of the workpiece through the arrangement of wires.

Wafer shape parameters from prior runs of simultaneously slicing a plurality of wafers from a workpiece in a wire saw having a sawing wire tensioned between wire guide rolls are used to alter the temperature profile of fixed and a moveable bearings at the ends of at least one wire guide roll, resulting in wafers with low waviness.

The invention discloses a multi-set clamping fixture for diamond machining, which is used for machining diamonds. The clamping fixture includes a base shell, a lip ring, and a sealing ring. The upper end of the base shell is opened, the lip ring is arranged at the inner ring position of the base shell, an embedding groove is arranged at the inner ring position of the lip ring, the sealing ring is arranged in the embedding groove, a vacuum cavity is formed in the base shell, and the base shell is externally connected with a vacuum pumping pipeline. After the pavilion portion of a diamond to be machined is inserted into the lip ring and supported by the sealing ring, a vacuum cavity is formed in the base shell, the vacuum cavity is vacuumized by the external pipeline, and then the diamond is limited at the position of the lip ring to complete the clamping process. The lip ring is connected with the base shell in a detachable structure. An annular air pressure cavity is arranged on the outer edge of the upper portion of the base shell, one ends of a plurality of auxiliary clamping rods are located in the air pressure cavity, and one ends of the auxiliary clamping rods radially pass through the inner annular surface of the air pressure cavity and the lip ring to be in contact with the diamond. Shaft seals are arranged at the positions where the auxiliary clamping rods pass through the inner annular surface of the air pressure cavity, and the clamping fixture further includes a cavity cover that is mounted on the upper portion of the base shell and covers and wraps the air pressure cavity. The air pressure cavity is internally connected with an external pressure air source pipeline.

Examples of automated gemstone feeding are described. According to an example, a gemstone feeding machine includes a conveyor belt assembly to feed holders carrying gemstones. The conveyor belt assembly can include a plurality of conveyor belts in two sets positioned parallel to each other and the two sets can move in opposite directions. Each belt in one set can be positioned alternately with respect to each belt in the other set. The assembly can include a fixed guiding plate at a first end of the conveyor belts and a detachable guiding plate adjacent to the loading assembly at a second end of the conveyor belts. The fixed guiding plate and the detachable guiding plate each comprises a plurality of transition profiles in alignment with immediately adjacent conveyor belts.

A gemstone detachment assembly includes a rotatable member which can temporarily attach thereto a gemstone holder detachably holding a rough gemstone exhibit a motion with the rotatable member for a partial path of rotation of the rotatable member. A detachment tool can be positioned in a path of the moving rough gemstone and can detach the rough gemstone from the gemstone holder. A magnet positioned in proximity of the rotatable member can temporarily hold holder onto the rotatable member. The magnet can generate a magnetic field which can hold the holder when in a first portion of the path of rotation of the rotatable member and can release the holder in a second portion of the path of rotation of the rotatable member.

A gemstone detachment assembly includes a rotatable member which can temporarily attach thereto a gemstone holder detachably holding a rough gemstone exhibit a motion with the rotatable member for a partial path of rotation of the rotatable member. A detachment tool can be positioned in a path of the moving rough gemstone and can detach the rough gemstone from the gemstone holder. A magnet positioned in proximity of the rotatable member can temporarily hold holder onto the rotatable member. The magnet can generate a magnetic field which can hold the holder when in a first portion of the path of rotation of the rotatable member and can release the holder in a second portion of the path of rotation of the rotatable member.