Workpiece holding device
A workpiece holding device capable of processing a workpiece with high accuracy. A holding section 3 in a processing apparatus 1 is a workpiece holding device that rotatably holds a workpiece W to be processed with a grinding stone 21 , the workpiece holding device including a base 34 , a chuck 33 that is composed of a material exhibiting a lower thermal expansion coefficient than that of the base 34 , is placed on the base 34 , and can adsorb and hold the workpiece W, and a clamping member 40 that is attached to the base 34 with gaps G 1 and G 2 between itself and the chuck 33 in a radial direction D of the base 34 and presses a flange 36 a of the chuck 33 against the base 34.
1 . A workpiece holding device that rotatably holds a workpiece to be processed with a grinding stone, the workpiece holding device comprising:
a base having a first matching element;
a chuck that is placed on the base and can adsorb and hold the workpiece, the chuck having a frame with a second matching element, wherein the first and second matching elements match each other and fit together; and
a clamping member that is attached to the base with a gap between the clamping member and the frame of the chuck in a radial direction of the base and presses a peripheral edge of the frame of the chuck against the base,
the clamping member comprising:
a main body section that is fastened to the base via a bolt,
a rotation stopper protrusion that is offset from the bolt in the radial direction of the base and supported on the main body section, the rotation stopper protrusion is fitted in a recess in the frame of the chuck to restrict rotation in a circumferential direction of the chuck relative to the base, wherein the gap is formed on each opposing side of the rotation stopper protrusion in a radial direction.
2 . The workpiece holding device according to claim 1 , wherein at least one of an opposite surface, which opposes the chuck, of the base and an opposite surface, which opposes the base, of the chuck is coated with an easy-slipping layer that urges the base to slip sideways relative to the chuck.
3 . The workpiece holding device according to claim 1 , wherein at least one of the base and the chuck is composed of a material that urges the base to slip sideways relative to the chuck.
4 . The workpiece holding device according to claim 1 , wherein at least one of a surface to be clamped, which opposes the clamping member, of the chuck and a clamping surface, which opposes the chuck, of the clamping member is coated with an easy-slipping layer that urges the clamping member to slip sideways relative to the chuck.
5 . The workpiece holding device according to claim 1 , wherein at least one of the chuck and the clamping member is composed of a material that urges the clamping member to slip sideways relative to the chuck.