Abstract: A pipe connection arrangement for a water tank of a heat exchanger of a motor vehicle heater includes a pipe equipped with a collar at a pipe end for inserting into a connecting sleeve at the water tank. The pipe is provided with a seal on a first side of the collar, with the seal being pressed tightly into a recess in the connecting sleeve. A holding clamp rests on the other side of the collar facing away from the seal with the holding clamp being formed asd a U-shape. The clamp is developed in such a way that its U-bracket-shaped part rests tightly against the pipe exterior. This design results in the load transmission being evenly transmitted over a relatively large surface area. The sleeve includes openings formed as slots for receiving the clamp, with a reinforcing web provided in the center of the slots. The clamp is secured by another gripping part that projects from the bracket part and engages behind a reinforcing web of the connecting sleeve.

Abstract: A panel heat exchanger is provided that has a plate made of a heat-conducting material and at least one pipe connected with it, this pipe having a meandering shape, and through which a heat exchange medium flows. The plate is provided with slots the width of which is adapted to the diameter of the pipe. The pipe is inserted into the slots approximately flush with the plate and is held by deformations extending transversely to its longitudinal axis at the slot edges in a form-fitting way.

Abstract: A heat exchanger is described that is constructed of several flat tubes arranged in parallel and at a distance to one another which, at their two front sides, are each closed off tightly. The end areas of the tubes are provided with connecting openings extending transversely to their longitudinal axis and leading to the adjacent flat tube or to the adjacent group of tubes. An advantage of the invention is its ease of manufacture.

Abstract: Disclosed is a heat exchanger, comprising a tube sheet comprised of plastic and having at least one opening for passage of a heat exchange fluid; and a heat exchanger tube sealed against the tube sheet at the opening, wherein the tube sheet includes in the region of each of the openings a sleeve-like connection nozzle in which an annular groove is defined by inner and outer parts of said nozzle. The groove extends coaxially to the opening and is open toward the heat exchanger tube and the end of the heat exchanger tube is pressed into the groove. The sleeve-like connection nozzles have a middle section (B), which is located in the plane of the tube sheet, and end sections, (A, C) which project on either side of the tube sheet.

Abstract: A coolant expansion tank, consists of a filling chamber for receiving the coolant and an expansion chamber connected via a connecting line and separated by a double-walled partition forming a monitorable testing space. The connecting line is led through and between the two walls of the double-walled partition. Openings to the exterior are provided in the testing space to dispurse any testing agent resulting from a leak in the partition or connecting line.

Abstract: A expansion tank for coolant consists of a filling chamber for receiving the coolant and an expansion chamber that is arranged under the filling chamber and is connected with it via a line between the upper area of the filling chamber and the lower area of the expansion chamber. An indentation portion of the filling chamber extends to the underside of the expansion tank and a suction outlet is connected to the indentation portion adjacent the underside of the expansion tank.

Abstract: Heat exchanger having a tube plate made of plastic, in which metallic tubes are fixed. The tube plate has elevations having openings for accommodating the tube ends, with the openings being subdivided into three sections in axial extension. The center section has the smallest cross-section and the end sections are in each case widened. The elevations extend on both sides of the tube plate, the total height of the elevations located in the area of an opening, inclusive of the tube plate thickness, being about 1.8 to 2.5 times the single tube plate thickness.

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.