Workpiece clamping device and workpiece transfer method

The invention discloses a workpiece clamping device and a workpiece transferring method. Wherein the workpiece clamping device comprises an integrated frame and at least two clamping fixtures; the integrated frame comprises a mounting plate and a cam turntable, the cam turntable is pivotally connected to the center of the mounting plate, and the cam turntable at least can rotate between a workpiece loosening position and a workpiece locking position; the clamping fixture is movably connected to the integrated frame, and one end of the clamping fixture is matched with the cam rotating disc and moves in the radial direction along with rotation of the cam rotating disc so that the other end of the clamping fixture can clamp or loosen the workpiece. The technical scheme is particularly suitable for clamping and transferring a large-aperture plane grating, the problem that the operation is tedious and dangerous in the clamping process in an existing method can be solved, rapid clamping, stable transferring, conven