Methods and machine tools for grinding discs. The machine tool comprises two grinding units with respective grinding spindles on which grinding wheels are arranged and a disc unit that comprises a disc spindle on which the disc to be grinded is arranged. The rotation axes of the grinding spindles are perpendicular to the disc spindle rotation axis. The grinding wheels comprise respective grinding surfaces which are perpendicular to the rotation axis of the disc spindle. The grinding surfaces have a width that is equal or greater than the width of the main surfaces of the disc. The two grinding units are configured to simultaneously move relative to the disc unit in an axis that is parallel to the rotation axis of the disc spindle and in opposite directions such that, in use, the grinding surfaces simultaneously contact opposite surfaces of the disc to grind them down.

Methods and machine tools for grinding discs. The machine tool comprises two grinding units with respective grinding spindles on which grinding wheels are arranged and a disc unit that comprises a disc spindle on which the disc to be grinded is arranged. The rotation axes of the grinding spindles are perpendicular to the disc spindle rotation axis. The grinding wheels comprise respective grinding surfaces which are perpendicular to the rotation axis of the disc spindle. The grinding surfaces have a width that is equal or greater than the width of the main surfaces of the disc. The two grinding units are configured to simultaneously move relative to the disc unit in an axis that is parallel to the rotation axis of the disc spindle and in opposite directions such that, in use, the grinding surfaces simultaneously contact opposite surfaces of the disc to grind them down.

A cam device includes a drive cam, a follower, a holding cam, and a restriction roller. The drive cam reciprocally rotates. The follower intermittently reciprocate linearly by the drive cam. The holding cam is rotationally driven integrally with the drive cam. The restriction roller is provided on the follower and restricts a movement of the follower by coming in contact with the holding cam. The holding cam separates from the restriction roller and the holding cam is in a holding release state, when the drive cam is in an engaged state with the follower.

The present invention relates to a method and a device for processing a hard-coated workpiece surface of a rotationally symmetrical workpiece (1) with at least one grinding wheel, wherein the method comprises the following steps: driving the workpiece (1) into a rotational motion around a workpiece axis of rotation (1.1), driving a grinding wheel (2a) into a rotational motion around a grinding wheel axis of rotation (2a.1), angulating the grinding wheel axis of rotation (2a.1) and the workpiece axis of rotation (1.1) to each other so that the grinding wheel axis of rotation (2a.1) and the workpiece axis of rotation (1.1) are not parallel, processing the workpiece surface with the grinding wheel (2a), wherein the grinding wheel (2a) is in contact with the workpiece surface.

A wafer polishing apparatus includes a lower surface plate, an upper surface plate disposed over the lower surface plate, a carrier disposed between the lower surface plate and the upper surface plate and containing a wafer, and a lift unit lifting the carrier such that an upper surface of the carrier contacts a lower surface of the upper surface plate or lowering the carrier such that a lower surface of the carrier contacts an upper surface of the lower surface plate.

A method for producing reinforced glass, reinforced glass and an electronic device are provided. The method for producing reinforced glass includes: subjecting glass to a first reinforcing treatment; detecting a first stress parameter of the glass subjected to the first reinforcing treatment, and determining whether the glass subjected to the first reinforcing treatment is qualified according to the first stress parameter; subjecting the glass to a second reinforcing treatment when the glass subjected to the first reinforcing treatment is qualified; detecting a second stress parameter of the glass subjected to the second reinforcing treatment, and determining whether the glass subjected to the second reinforcing treatment is qualified according to the second stress parameter; and subjecting the glass to a touch-polishing treatment when the glass subjected to the second reinforcing treatment is qualified, so as to obtain the reinforced glass.

A method for producing reinforced glass, reinforced glass and an electronic device are provided. The method for producing reinforced glass includes: subjecting glass to a first reinforcing treatment; detecting a first stress parameter of the glass subjected to the first reinforcing treatment, and determining whether the glass subjected to the first reinforcing treatment is qualified according to the first stress parameter; subjecting the glass to a second reinforcing treatment when the glass subjected to the first reinforcing treatment is qualified; detecting a second stress parameter of the glass subjected to the second reinforcing treatment, and determining whether the glass subjected to the second reinforcing treatment is qualified according to the second stress parameter; and subjecting the glass to a touch-polishing treatment when the glass subjected to the second reinforcing treatment is qualified, so as to obtain the reinforced glass.

Disclosed herein is an apparatus for grinding a compression line spring. The apparatus includes a lower chain conveyor (100), an upper chain conveyor (200), and grinding units (300). The lower chain conveyor includes chain units each having first support blocks (115) for supporting compression line springs. The upper chain conveyor includes chain units each having second support blocks (215) for compressing downward upper portions of the compression line springs and thus supporting the compression line springs. The grinding units grind seat surfaces formed on opposite ends of the compression line springs that are moved by the upper and lower chain conveyors. A V-shaped depression (115a) is formed in each first support block so that each of the compression line springs is seated onto the corresponding V-shaped depression. A lower surface (215a) of the second support block that compresses the compression line springs has a planar structure.

Disclosed herein is an apparatus for grinding a compression line spring. The apparatus includes a lower chain conveyor (100), an upper chain conveyor (200), and grinding units (300). The lower chain conveyor includes chain units each having first support blocks (115) for supporting compression line springs. The upper chain conveyor includes chain units each having second support blocks (215) for compressing downward upper portions of the compression line springs and thus supporting the compression line springs. The grinding units grind seat surfaces formed on opposite ends of the compression line springs that are moved by the upper and lower chain conveyors. A V-shaped depression (115a) is formed in each first support block so that each of the compression line springs is seated onto the corresponding V-shaped depression. A lower surface (215a) of the second support block that compresses the compression line springs has a planar structure.

A method of producing a carrier for use in a double-side polishing apparatus, the method including engaging an insert with a holding hole formed in a carrier body and sticking the insert to the holding hole, the carrier body being configured to be disposed between upper and lower turn tables to which polishing pads are attached of the double-side polishing apparatus, the holding hole being configured to hold a wafer during polishing, the insert being configured to contact an edge of the wafer to be held, the method including: performing a lapping process and a polishing process on the insert; engaging the insert subjected to the lapping process and the polishing process with the holding hole of the carrier body; and sticking and drying the engaged insert while applying a load to the insert in a direction perpendicular to main surfaces of the carrier body.