A sheet punching and embossing machine includes a device for punching blanks from sheets. The device has a frame and a bearing plate is mountable in the frame. The bearing plate is equipped with punching and grooving knives. Hydraulically activated clamping elements are provided for clamping the bearing plate in the frame. A hydraulic system includes a piston braced by a mechanical spring for building up hydraulic pressure for activating the clamping elements.