Abstract: A ventilation unit for heating or air-conditioning in a motor vehicle. The unit includes a blower and a heat exchanger, with a diffuser positioned in the flow of air from the blower. The diffuser spreads the air flow so that it substantially covers the heat exchanger area. A grid positioned between the diffuser and the heat exchanger aids in spreading the flow of air to the peripheral portions of the heat exchanger.

Abstract: An oil cooler arrangement for internal-combustion engines is described which is used in particular for installation between the engine and an oil filter. The heat exchange space of this oil cooler through which the oil flows is formed as a housing chamber into which a heat exchange body is tightly placed through which the coolant, in particular, water, flows. The heat exchange body includes many parallel pipes, the ends of which are held in the bottoms of two oppositely disposed coolant collecting spaces. This design permits the production of oil coolers without soldering or welding processes. The water flow-through through the parallel pipes is also exactly defined.

Abstract: For the filtering of supply air, especially in the case of motor vehicles, a filter that is divided into two parts is arranged inside a housing. The two parts of the filter can be swivelled apart around swivel shafts arranged in their end areas so that, when required, an air passage means can be exposed for the passage of unfiltered air.

Abstract: Disclosed is a fluid friction clutch having front and rear working gaps, which are connected to one another in a manner which provides more continuous and uniform distribution of the torque-transmitting viscous medium between the gaps. The clutch includes at least one bore through the drive disk which separates the front and rear working gaps. The bore is positioned in annular grooves which are provided in the drive disk at the same radial distance as the bore and which further include baffles positioned in the grooves to block the flow of fluid around the annular grooves and to promote flow through the bore. A similar groove/baffle arrangement is provided as a return means on the rear side of the drive disk near to the outer periphery.

Abstract: A carrier matrix for a catalytic reactor for the purification of the exhaust gas of internal combustion engines, comprising a flat foil and a corrugated foil arranged in alternating layers. Exhaust gas flows through the ducts formed by the corrugations of the corrugated foil and the flat foil surface. The corrugations have a plurality of segments fluidly connected behind one another in flow direction, but are transversely staggered with respect to flow direction. This staggered arrangement increases the turbulence of the gas flowing through the ducts, thereby increasing the effectiveness of the matrix. The matrix can be manufactured in a simple manner yet permits a good utilization of the catalyst materials coated on the foils.

Abstract: Disclosed is a method and apparatus for controlling the output speed of a fluid friction clutch. The fluid friction clutch comprises a work chamber, in which a drive disk rotates, and a reservoir. A valve controls the circulation of a viscous medium between the work chamber and the reservoir. The output rotational speed is thus dependent on the filling ratio of the work chamber. The valve is actuated as a function of at least one control parameter by means of a stepping motor connected with the clutch. The control parameter is preferably the temperature of the cooling medium of an internal combustion engine. The rotational output of the stepping motor is converted to a linear motion to actuate the valve lever by means of a spindle drive.

Abstract: A matrix for a catalytic reactor used for exhaust gas purification in internal combustion engines includes corrugated strips of sheet steel that are coatable with catalyst material. The sheets are folded to produce several layers in a tubular housing which is traversed by a flow of exhaust gases. The individual layers are part of a continuous length or strip of sheet steel which is folded in a meandering or serpentine fashion. A zigzag folding pattern is especially preferred. This arrangement simplifies manufacturing and results in improved radial equalization of exhaust gases. Uniformity of flow profile is improved by cutouts provided in the matrix material.

Abstract: A device is provided for protecting the coolant circulation in an internal combustion engine, especially a motor vehicle engine, from excess pressure. A first pressure control valve is arranged in the upper region of a coolant-carrying tank and adjusted to a first opening pressure. A float is arranged in the tank which, in a sealing manner, can be engaged with a lead-in to the pressure control valve so that, in the case of an excessive rise of the coolant in the tank, the pressure control valve is not operative. The ejection of cooling water in the switch-off phase of a previously heated internal combustion engine is thereby prevented. In order to avoid an unacceptable increase of pressure in the coolant-circulating system, a second pressure control valve is provided which is designed for a higher opening pressure than the first one. As a result, the coolant-circulating system is protected from excessive pressures.

Abstract: A slide valve with a partial-vacuum actuator, especially for motor vehicle heating and air conditioning units, comprising a valve housing having a bottom; a slide for opening and closing the valve; a slide chamber for slidably containing the slide; an actuating rod connected with the slide, and for actuating the slide; a partial-vacuum actuator for actuating the actuating rod, and having a first housing section integral with the valve housing; a flat seal for sealing the sliding chamber, and for surrounding and sealing the actuating rod; a support for holding the flat seal against the bottom of the valve housing; and a bayonet mount with detent mechanism for fastening and securing the support inside the first housing section.

Abstract: Disclosed is a fluid friction clutch controlled as a function of temperature and/or rotation speed, comprising a driving primary member comprising a first reservoir chamber and an overflow orifice, wherein the primary member further comprises a device, responsive to the rotation speed of the primary member, for controlling the flow of a working fluid through the overflow orifice; a driven secondary member surrounding the primary member and optionally comprising a partition which defines a second reservoir chamber; a working chamber disposed between the primary and secondary members, optionally comprising pump means for controlling the flow of working fluid from the working chamber to the second reservoir, and an optional valve, located in the partition and being responsive to temperature, for controlling the flow of working fluid between the second reservoir chamber and the working chamber.

Abstract: A fluid friction clutch is provided having an intermediate wall, disposed in a housing and separating the clutch fluid supply or storage space and the clutch fluid working space, with a plurality of overflow openings therein at circumferentially spaced locations. The clutch fluid primarily enters the working space from the storage space through a controllable supply inlet opening in the intermediate wall. The supply inlet is thermostatically controlled by a bi-metal element. A rotating clutch disk is provided in the working space, and at least one clutch fluid return bore is provided in the intermediate wall in the region adjacent the outer circumference of the clutch disk. These return bores provide return guidance for clutch fluid into the storage space.

Abstract: Disclosed is a heating and/or air-conditioning installation for automotive vehicles comprising at least one blower and a flap for affecting the flow of air, and an electronic control device for rotational speed control or speed shifting. The control device which comprises one or more electronic components capable of generating significant amounts of heat, is mounted on the flap, in order to cool the electronic components while only minimally interfering with the flow of air in the heating and/or air-conditioning installation.

Abstract: A fluid friction clutch is disclosed which has a working chamber formed by an output component in which a driving disk that is connected with an input component can rotate. For the adjustment of the degree of clutching, the working chamber can be filled by fluid supplied from a reservoir chamber developed as a pressure chamber and connected with the working chamber via a fluid connection, such as a pipe, a borehole, or similar means. This fluid connection is developed in such a way that, by means of admitting compressed air to the reservoir chamber, fluid can be delivered in a controlled manner from said reservoir chamber into the working chamber. A fluid friction clutch of this type has not movable mechanical valve parts, which is particularly advantageous when the compressed air is admitted to the reservoir chamber in surges, which would result in a rapid wear in the case of the known embodiments.

Abstract: Disclosed is an evaporator, particularly for air conditioning installations in automotive vehicles, comprising an evaporator block including several evaporator tubes and coolant supply means. The coolant supply means comprise an expansion valve, a feed tube and a manifold from which the evaporator tubes extend. A calming line segment for the coolant is arranged within the manifold. A distributing space connected with the calming segment is located adjacent to the calming segment. Means are provided for deflecting the coolant between the calming segment and the distributor space.

Abstract: An arrangement is disclosed for joining the tubes of a heat exchanger core to a connecting box, wherein the tubes are fastened to the connecting box and sealed, said tubes being secured to the connecting box by means of a friction joint and at least one space being provided for each tube surrounding the end of the tube; each said space comprising a cavity bounded by the connecting box and the tube or a corresponding recess, and being filled and sealed with adhesive material.

Abstract: The invention concerns a heat exchanger comprising a heat exchanger block having a plurality of tubes and fins arranged transversely to the tubes, at least one tube plate and a water tank, both made of a synthetic plastic material. The tube plate has orifices to receive the ends of the tubes and the water tank is fastened in a water tight manner to the tube plate. In order to obtain a simple and reliable joint of the heat exchanger tubes with the tube plate and the water tank with the tube plate, the plastic tube plate is provided on one side with projections. The orifices are located in these projections and the ends of the tubes are mounted in these orifices by expansion in the radial direction or impression in the axial direction. Both the tube plate and the water tank are equipped with flat surfaces at their edges. These surfaces rest on each other and the tube plate is joined with the water tank by vibration welding on these surfaces.

Abstract: The invention relates to a method for joining tubular parts of a heat exchanger that are inserted into each other, as well as to a tool for practicing the method.

Abstract: Disclosed is a fan drive, in particular one for cooling installations of rail vehicles. The fan drive comprises a hydraulic motor and a control valve which regulates a bypass as a function of temperature, thus affecting the flow of a pressure medium driving the motor. The control valve comprises a control piston subjected to a control pressure in the direction of closing the bypass, and a counterbalancing pressure in the opposite direction from the source of the pressure medium. The control valve also comprises a control spring which biases the control piston in the direction of closing the valve, and a pilot valve which affects the control pressure. The pilot valve is actuated by an electromechanical servo component. The pilot valve is located in an insert which is arranged within the control piston. A central bore of the control piston is slidingly guided on the convex surface of the insert so as to form a seal.

Abstract: A regulator circuit for controlling the cooling and heating power for automotive vehicles, wherein signals proportional to the external temperature, the internal temperature of the vehicle, and the desired temperature are applied to an input amplifier, the output signal of this amplifier being applied as the desired value to the heating system. This output signal is also fed to a second amplifier which is furthermore supplied with the signal proportional to the external temperature. The output signal of this second amplifier serves as the desired value for the cooling system. By means of this arrangement, excessive cooling at the transition point between heating and cooling, as well as oscillation around this transition point, can be prevented. An economical reheat operation is made possible for dehumidifying the air by appropriate selection of resistor values such that the heating system and the cooling system are in simultaneous operation.

Abstract: An axial fan arrangement is provided, especially for the radiator of a water cooled internal combustion engine for commercial vehicles. In order to reduce noise levels without impairing fan efficiency, an air guide structure is provided which widens in the flow direction starting from adjacent the air inlet edges of the fan blades. Embodiments are included which have part of the air guide structure carried by the fan blades and other embodiments have fixed air guide structure. The contour of the air guide structure conforms to the facing contour of the fan blades.