Abstract: A heat exchanger, particularly for use in heat pumps, either as an evaporator or as a condenser or both, comprises for the flow of a refrigerant one or more pipes helically coiled around a core pipe. This structure is mounted inside a mantle-pipe which serves for the flow of a heat carrying medium, such as water, and is helically coiled around a vertical axis or bent to another compacted shape making the center line of the turns of the helically coiled pipe or pipes extend horizontally or at a slight inclination to the horizontal. The refrigerant is fed to one end of the helically coiled pipe or pipes and then flows back through the core pipe. The heat carrying medium flows through the mantle-pipe in the same general direction as the flow of refrigerant through the helically coiled pipes.

Abstract: A combined fixture and cooling device for the mounting and cooling of fluorescent tubes and made by extrusion of a heat conductive material so as to constitute a cooling tube having an upper wall, a pair of side walls and a concave, part-cylindrical lower wall defining a contact face for the upper surface of a fluorescent tube, the side walls of the cooling tube being provided with lengthwise extending ribs or grooves to provide fastening means for mounting the fluorescent tube on the cooling tube with its upper surface in contact with the contact face of the cooling tube.The fluorescent tube is mounted in sockets associated with cylindrical casings of the same diameter as the fluorescent tubes and including ballast means for the fluorescent tubes, and the cylindrical casings are mounted on the cooling tube by means of spring clips embracing the lower part of the casings and engaging the ribs or grooves of the side walls of the cooling tube.