Device for detachably fastening a box

In a press having a mold table and a removable mold block insertable therein, the improvement comprising a device for inserting and detachably fastening the insertable mold block in an operating position on the mold table, said mold table and the insertable block having thereon laterally opposite guide members, lifting means on said mold table for holding the mold block against downward-oriented adjusting surfaces of said guide members on said mold table in the operating position, said block having a surface with a mold feed opening therein, said block surface and the adjusting surfaces provided on the mold table define a common plane when said mold block is in the operating position, said mold table is U-shaped in horizontal cross-section and has a pair of legs having inner sides, there being opposite guide grooves defined on said inner sides by said opposite guide members, at least one mold carrier in said guide grooves for supporting support surfaces on said mold block.