Abstract: A disconnectable link may include a first link member having a generally tubular portion, a first ball joint disposed on the first link member and adapted to engage a first suspension member; a second link member slidably receivable within the first link member; a second ball joint disposed on the second link member and adapted to engage a second suspension member; a lock shaft engaged with the second link member; and a lock element disposed within an aperture in the second link member. Movement of the lock shaft into a first position may cause the lock element to engage the first link member to prevent relative axial movement between the first and second link members, and movement of the lock shaft into a second position may cause the lock element to disengage the first link member to allow relative axial movement between the first and second link members.

Abstract: A disconnectable link may include a first link member having a generally tubular portion, a first ball joint disposed on the first link member and adapted to engage a first suspension member; a second link member slidably receivable within the first link member; a second ball joint disposed on the second link member and adapted to engage a second suspension member; a lock shaft engaged with the second link member; and a lock element disposed within an aperture in the second link member. Movement of the lock shaft into a first position may cause the lock element to engage the first link member to prevent relative axial movement between the first and second link members, and movement of the lock shaft into a second position may cause the lock element to disengage the first link member to allow relative axial movement between the first and second link members.

Abstract: A method for reducing expression of a target gene in a mammalian cell is provided. The method comprises (a) introducing siRNA into a first mammalian cell such that expression of the target gene is reduced in the first mammalian cell, and (b) exposing a second mammalian cell which does not contain siRNA that reduces expression of the target gene to the siRNA-containing first mammalian cell, thereby resulting in reduced expression of the target gene in the second mammalian cell. An additional aspect provides a method of reducing expression of a target gene in a mammal. Yet another aspect provides a mammalian cell transfected with an expression vector which directs expression of siRNA for a target gene such that expression of the target gene is reduced in the transfected mammalian cell, and the siRNA expression level is sufficient to signal reduction of target gene expression in a mammalian cell not transfected with siRNA for the target gene.

Abstract: An axial-flow fan comprises a hub having an axial dimension T.sub.N, and including a planar portion extending in a radial direction. Axial blades connected to the hub, and each axial blade has an axial dimension T.sub.Sch in a vicinity of a radially outermost portion of the hub. The axial dimension T.sub.Sch of each axial blade is greater than the axial dimension T.sub.N of the hub. Each axial blade has a projection U beyond the planar portion of the hub. The projection U extends axially from a leading edge of each axial blade to the planar portion of the hub.

Abstract: A radiator fan of an internal combustion engine in a motor vehicle is provided in the form of a one piece injection molded combination of radial fan blades and axial fan blades supported on a conical annulus for increasing air pressure flow across the radiator. The conical annulus has the same axis as that of the hub of the fan. The radial blades connect the interior face of the conical annulus to the hub of the fan. The axial blades are connected to the exterior surface of the conical annulus and extend radially outward. The fan is coupled to the engine through a fluid friction clutch. An air guide ring is positioned upstream of the fan for deflecting axial incoming air flow to help improving efficiency of the fan.

Abstract: An axial fan arrangement for the radiator of an internal combustion engine including an annular bypass channel terminating between the fan frame and the fan. The bypass channel is open to the pressure sided of the fan and is designed such that the bypass flow emerging on the intake side of the fan is deflected in the direction of the main flow. By these measures the stabilization of a back flow vortex is rendered unnecessary.

Abstract: A fan for a cooling system of a motor vehicle has a closed impeller with a plurality of radial vanes, each of which is provided with an essentially radially oriented vane base. The radial vanes extend in a generally radial direction with respect to an axis of rotation of the impeller. An inner contour of the vanes is defined by leading edges of the vanes, and an outer contour of the vanes being defined by trailing edges of the vanes. The exterior diameter of the outer contour of the radial vanes and the interior diameter of the inner contour of the radial vanes decrease in a direction from the cover disk toward the impeller bottom.

Abstract: A fan for a cooling system of a motor vehicle has a radial impeller with multiple vanes which are arranged between an impeller bottom and a cover disk. A stationary intake nozzle extends axially into a cover disk intake, forming an annular gap between the cover disk intake and the intake nozzle. The impeller bottom, the vanes and the cover disk of the radial impeller are made in one piece of a plastic material. A separate air guide ring is arranged on the cover disk at the cover disk intake.

Abstract: A cooling system for a vehicle having an internal-combustion engine has a plurality of cooling circuits with heat exchangers for each circuit. The temperatures of different cooling media are measured and processed in a switching device to form an output signal which serves to control a fan. In this way, the air flow through the heat exchangers can be varied depending on measured temperature conditions. Individual capacity control of each cooling circuit is possible, thereby preventing unfavorable operating conditions in the individual circuits. The cooling capacity demand of the individual cooling circuits is determined by a central control unit which receives signals from temperature sensors in each circuit. The central control unit includes a microprocessor. Each cooling circuit has an actuating means for individually controlling the capacity of the relevant heat exchanger.

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: An air conveying device is provided on a radiator for water cooled internal combustion engines. The device comprises a fan rotor supported on the internal combustion engine by means of a fan rotor shaft on which is located a belt pulley for a driving belt. A fan shroud surrounds the outer ends of the fan blades and is fastened to the blade tips. So that even belts with a relatively short belt length can be installed from the fan rotor direction, the fan shroud has at least one slot extending in the axial direction for inserting the belt and for slipping the length of belt which is positioned at the shaft-free end of the fan rotor over the fan shroud.

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: 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.

Abstract: A fan wheel or pre-guide wheel for axial or semi-axial air flow, especially for use with the cooling systems of motor vehicles. In order to provide for advantageous stream line flow, the leading surfaces of the fan wheel hub or an upstream pre-guide wheel hub are suitably rounded providing for a generally increasing hub diameter in the direction of the air flow. In order to simplify the casting or extrusion of the fan wheel so configured, the invention provides for a substantially cylindrical or conically decreasing hub diameter in the region of the fan hub lying generally behind each fan blade. For fan hubs of relatively low axial depth, for example with riveted fan blades, the gaps may remain uncovered without detrimental effects on the air stream.

Abstract: Disclosed is a fluid friction clutch, comprising a drive disk having at least one first working surface; a housing enclosing said drive disk and being mounted rotatably with respect thereto, the housing including at least one second working surface in spaced relationship with the first working surface to form a gap therebetween; a device for selectively introducing a fluid working medium into the gap; and a device for removing the fluid working medium from the gap, wherein the first and/or second working surfaces comprise roughened surfaces.

Abstract: Disclosed is a fluid friction clutch, preferably for driving the fan in an automotive cooling system, comprising a driven disk member; a drivable housing member surrounding the driven disk member in such a manner as to provide a working chamber therebetween for receiving a fluid capable of transmitting rotational force between the driven disk member and the housing member; a reservoir separate from the working chamber for containing the fluid; a selectively openable and closable inlet orifice providing fluid communication between the reservoir and the working chamber; a return conduit providing fluid communication between the working chamber and the reservoir; and a supplemental disk member rotatable with the driven disk member and positioned within the reservoir so as to be wetted by the fluid at least when the fluid friction clutch is at rest.

Abstract: A motor vehicle, especially a truck, with a cab and a cooling system for an internal combustion engine is disclosed. The cooling system comprises a heat exchanger disposed in an engine compartment and provided with an associated blower, and at least one additional heat exchanger located outside the engine compartment and with which an additional blower is associated. The additional blower is mounted on a roof of the cab and is connected through a channel with the additional heat exchanger which is located inside the channel in the vicinity of one wall of the cab.

Abstract: The air flow between the outlet of a centrifugal fan and the inlet of a surrounding annular radiator or heat exchanger for cooling an internal combustion engine is made uniform by rounding the peripheral edges of the fan wheel support discs so as to enlarge the effective outlet channel for the air and to guide the air in the direction of the lateral regions of the radiator. One or more baffle rings controls the short circuit flow to the inlet of the fan as well as the leakage flow at the shaft side of the fan.

Abstract: A motor vehicle, especially a truck, with a cooling device for an internal combustion engine is disclosed. The cooling device comprises at least one heat exchanger which is mounted in an elevated position on top of or behind a cab of the vehicle. A liquid-collecting container is located at least beneath the heat exchanger of the cooling device to protect the vehicle occupants against scalding in the event the heat exchanger is damaged as in an accident.

Abstract: A quiet cooling system for internal combustion engines includes a radial impeller and a ring radiator. The ring radiator is disposed in the vicinity of the circumference of the radial impeller and is spaced at a distance from the impeller. The ring radiator can be made integral or in the form of segments. The radiator includes cooling water tubes which are to carry water and have fins fastened thereto. The cooling water tubes run parallel to the fan axis and are positioned parallel to the flow direction of cooling air leaving the radial impeller.