A holding apparatus for grinding members includes two clamping disks that have respectively a plurality of anchor plates and a plurality of anchor slots on different perimeters. 3D meshes are represented by topology data, geometry data and property data. The main control board is disposed horizontally above the conveying space when viewed from the front. A transmitreceive switch coupled to the output of the modulator is selectively operative between a first transmit position and a second receive position. The advantage of such a diagonal gasket support is that a contact-free support at the diagonal gasket is obtained. In this way, after a power outage, the location of recently written logical units can be determined without having to perform a scanning during initialization.