A machine frame for a high-pressure roller press for receiving the rollers in the bearings of the press, including at least one first frame element below the rollers and at least one second frame element. In the present invention, a recess groove 9 extending in a direction in which keyboards 3 are arranged is formed at an upper portion of a back panel 4 of the electronic keyboard instrument 1, a locking edge 8a formed at an upper edge of a speaker cover 8 is fitted into the recess groove 9, and a lower edge of the speaker cover 8 is fixed to a lower portion of the back panel 4 by a screw 11. A connection setup cell is transmitted to a next-hop ATM switch to ensure a connection dedicated to transfer of tho series of packets. The valve body has a main valve seat. For example, an on-screen image, such as text or a graphic, can be generated for display over the graphical user interface. A pump unit having a can of this type is also provided.