Abstract: The invention relates to a filter for cleaning lubricating oil, especially for internal combustion engines of motor vehicles, with a filter case which, when installed, is in an at least approximately upright position. It has a cylinder-shaped oil filter cartridge and an inlet for the dirty oil flowing through the filter cartridge, plus an outlet for clean oil connected to the central interior part of the filter case and situated in a base at the bottom end of the filter case. A drain passage at the bottom end of the filter case becomes connected to the inlet chamber of the filter case whenever the filter cartridge is removed, plus a closure which cuts the drain passage off from the filter case.

Abstract: The invention relates to a filter for cleaning lubricating oil, especially for internal combustion engines of motor vehicles, with a filter case which, when installed, is in an at least approximately upright position. It has a cylinder-shaped oil filter cartridge and an inlet for the dirty oil flowing through the filter cartridge, plus an outlet for clean oil connected to the central interior part of the filter case and situated in a base at the bottom end of the filter case. A drain passage at the bottom end of the filter case becomes connected to the inlet chamber of the filter case whenever the filter cartridge is removed, plus a closure which cuts the drain passage off from the filter case.

Abstract: The invention relates to a fuel preheater, especially for use in diesel engines of motor vehicles, in which the fuel, as a first fluid medium, is heated by absorbing heat from a second fluid medium of higher temperature, and in which the two media are carried through the preheater in separate passages. The preheater has a core which consists substantially of a set of walls of meandering cross section which forms two groups of parallel passages opening alternately on one longitudinal side and the other longitudinal side and running between the individual walls of the set the passages of one group being all open on the same side. The core is disposed between two covers covering the open longitudinal sides of the passages.

Abstract: The invention relates to a heat exchanger for two fluid media, especially liquids, having a housing which can be closed with a cover and which has a core for separately carrying the two media under heat exchange, at least the core being able to be produced by pressure casting. The core (3) is formed essentially of a train of walls in a meandering configuration which form the passages for the two media in the form of tall, narrow chambers, while the one medium and the other flow alternately through adjacent chambers. The chambers are divided into partial chambers disposed in two planes through which the fluid flows successively, by a common partition wall (34) which divides all the chambers vertically and is integral with the train of walls.

Abstract: A heat exchanger for two fluids, especially an oil cooler for oil and water in an internal combustion engine. The heat exchanger is made up of a dividing wall having a meander-like cross section which is bounded by two side covers to form longitudinal channels and having a headering system comprising cross channels, connecting channels, feed channels, and inlet and outlet openings located at each end of the heat exchanger. The heat exchanger is of modular design so that it can be easily expanded by the connection of several heat exchanger units.