Abstract: Oxygen generator for cartridges, having a pressure tank and a cartridge holder connected thereto. The cartridge holder is divided by a gas-tight separable joint into two halves, and its interior is in communication through an opening with the interior of the pressure tank. To maintain functionality over a long period of time, the bottom half of the cartridge holder is joined to the pressure tank with good thermal conductivity in the area of the separable joint and is in communication with the pressure tank through an unplugged opening which is narrow in proportion to the inside cross section of the lower half. Further, the upper half of the cartridge holder is superimposed on the bottom half directly at the top of the pressure tank and is provided with a cooling structure.

Abstract: The invention relates to a tube cutter, especially for plastic tubes, which comprises a housing that can surround the tube and having a rotation guide gripping the tube. The tube cutter has a cutting tool which can be sunk into the outer surface of the tube, having a lengthwise guide and a tool holder movable therein. The cutting tool has a cutting edge which runs at an angle to the direction of movement of the tool holder and lies substantially in a plane passing through the rotational axis. By these means it is possible to produce bevels with the cutting edge.

Abstract: An expanding head for pipe end enlarging tools which have a tool body including a cylindrical end portion and a removable mandrel having a tapered end extending through the cylindrical end portion of the body and axially movable therein. The expanding head comprises a plurality of exchangeable segmental expanding elements each having a flange segment which together form a radially outwardly extending annular flange. The segments are connected together to unite them as a self-contained set and for radial movement in response to axial movement of the mandrel when in use. The segments are connected by a spring element which surrounds the segments at the annular flange and clamps them against each other and against the mandrel. The segments are removably connected to the cylndrical portion of the tool body without detachment of the spring element to maintain the segments in the self-contained set.

Abstract: A device for mounting exchangeable flanged sets of expanding elements on a tool for enlarging the ends of pipes. The tool comprises a tool body having an expanding mandrel and a removable cap for retaining the sets of elements on the mandrel. The device comprises a carrier having a plurality of orifices each for the insertion of one set of expanding elements. The carrier is removably mounted on the tool body and the sets of expanding elements are releasably retained in the orifices.