Abstract: A multichannel flat tube for a heat exchanger has a plurality of parallel flow channels aligned in a row, side by side, along a transverse axis of the tube. At least the inner flow channels have oval cross-sections, and major semiaxes of the inner flow channels are inclined relative to the transverse axis of the tube at an acute angle. The flat tube can be designed for high operating pressures with relatively low weight and relatively high heat exchange capability. The construction may be used, for example, in CO2 air conditioners in motor vehicles.

Abstract: A multichannel flat tube for a heat exchanger has a plurality of parallel flow channels aligned in a row, side by side, along a transverse axis of the tube. At least the inner flow channels have oval cross-sections, and major semiaxes of the inner flow channels are inclined relative to the transverse axis of the tube at an acute angle. The flat tube can be designed for high operating pressures with relatively low weight and relatively high heat exchange capability. The construction may be used, for example, in CO2 air conditioners in motor vehicles.

Abstract: A battery-operated device, for example, a blood pressure measuring device, consists essentially of a housing (2) and a compartment (3) to accommodate batteries. The compartment (3) is rotatably hinge-connected to the housing (2). The compartment (3) can be pivoted between an insertion position (E) for receiving batteries and an operating position (B). The device (1) has a standing surface (15). The compartment (3) for accommodating batteries is arranged so that the outside surface (4) of the compartment (3) in the operating position (B) forms part of one of the side walls (16a, 16b, 16c), and the inside (8) of compartment (3) is open at the top to receive batteries in the insertion position (E).

Abstract: A heat exchanger, produced by the insertion of welded pipes into a rib pack, has a good connection between the rib pack and the pipes after expansion of the pipes. An optimal contact of the pipes against the passages in the cooling fins of the rib pack is achieved because the weld base of the welded pipe lies in a recess. The recess is formed by reduction of the wall thickness of a strip material from which the welded pipe is produced.

Abstract: A support for endless grinding sleeves for grinding workpieces has a casing which axially running slots or grooves and the support has a round outline in cross section. An axial hole through the support becomes narrower along its length and is designed to receive a wedging cone that is to be drivingly joined with a shaft. The outer surface of the support is made somewhat smaller in size than the inner circumference of the endless grinding sleeve that is to be placed on the support and the cone is driven into the support to radially expand it into engagement with the sleeve.

Abstract: Disclosed is a drive mechanism for a slide projector adapted for accepting a circular slide magazine of the type including an approximately h-shaped configuration wall having a pair of forked inner and outer wall parts in coaxial spaced relationship located near the axial end of the housing which abuts the projector, the outer wall part having on its side facing the inner wall part a plurality of recesses corresponding in number to the slide compartments. The drive mechanisms for selectively rotating the slide magazine comprises a drive member mounted for rotation on the projector housing at a location adjacent the h-shaped wall configuration of a mounted slide magazine, and at least one drive pin mounted excentrically on the drive member substantially parallel to the axis of rotation of the drive member, for projecting into the space between the inner and outer wall parts of the h-shaped configuration.