Abstract: The utilization of double fans for engine cooling of motor vehicles is known. Said fans generate a flow of air which then serves to cool a heat exchanger, in particular a coolant radiator for motor vehicles. The double fan is herein characterized by an optimal use of the surface of the coolant radiator that is to be cooled, so as to be able to achieve a cooling performance as high as possible. The assembly of the double fan has up to now been such that a separate electric motor is provided for each blower. The double fan (1) for a heat exchanger (2), in particular a coolant radiator of a motor vehicle, has a first blower (4) and a second blower (5). According to the invention, the first driven blower (4) drives the second blower (5) by way of a transmission element (10) provided on the outer surface (11) of the first blower and an outer surface (12) of the second blower (5). The double fan is provided for a heat exchanger, in particular a coolant radiator of a motor vehicle.

Abstract: A drive unit, in particular for a fan in motor vehicles, is indicated, comprising an electric motor (12) operated on a DC line (UBat), and comprising a device (13) for controlling the speed of the motor (12) by changing the operating voltage applied at the motor (12).

Abstract: The invention is based on a method for producing a common carrying part (3) for an electrical drive, whereby a bottom region (2) is formed on the common carrying part (3) that can be produced having various axial lengths and diameters,

Abstract: The invention is based on a cooling fan (10) with a frame (12), having a baffle apparatus (14) with an electric motor (16) fastened to it which drives a fan propeller (18). The invention proposes that a control unit (20) for the electric motor (16) be integrated into the frame (12).

Abstract: A drive unit, in particular for a fan in motor vehicles, is indicated, comprising an electric motor (12) operated on a DC line (UBat), and comprising a device (13) for controlling the speed of the motor (12) by changing the operating voltage applied at the motor (12). In order to cost-effectively realize a stepwise adjustment of the motor speed, the speed control device (13) comprises a plurality of resistors (R1-R3) and a plurality of semiconductor switches (T1-T3) for selectively connecting the motor (12) in series with at least one of the resistors (R1-R3) (FIG. 1).

Abstract: A method of balancing an electronically driven air blower unit comprising a radial blower with a high-speed electronically commutated d.c. motor which drives the blower and which is of external rotor design, utilizing a balancing device into which the completely mounted air blower unit (1) can be inserted, without housing lid, and with which electrical contact (101, 102, 103; 201, 202, 203) can be made. The balancing device is provided with a control device for the motor (3, 4, 5) of the air blower unit and with a device (9) for bridging the motor electronics (10) of the air blower unit (1) itself. In order to drive the part to balanced of the air blower unit, its electromechanical transducer (3, 4, 5) is used, which for this purpose is actuated by the control device provided in the balancing device. The balancing process is essentially carried out in two compensation planes which are spaced axially from one another and are parallel with one another.

Abstract: An apparatus for producing a fresh air stream, has a blower connectable at a pressure side with an exhaust gas conduit of an internal combustion engine of a motor vehicle, a fresh air supply element communicatable with the exhaust gas conduit, a check valve provided between the blower and an opening of the fresh air supply element into the exhaust gas conduit, a cut-off arranged in the fresh air supply element between the check valve and its opening into the exhaust gas conduit and having a closing member loaded with a spring force toward a closing position, an actuating member for the closing member, and a bypass branching from the fresh air supply element so that a pressure which builds when the blower operates and is supplied through the bypass to the actuating member for the closing member acts opposite to the spring force.

Abstract: The fan housing for a multistage fan has a first housing part for receiving the electric motor, a second housing part mounted coaxially on the first housing part, and a housing cover mounted on the opposing side of the second housing part. So that fan noise is minimize during fan operation, for improved protection from external effects and to avoid tension originating from thermal expansion in the blower housing the housing cover for the second housing part has a peripheral cover edge portion and is pot-shaped or cap-shaped; the housing cover completely overlaps the second housing part; an overlapping peripheral portion of this housing cover has a radial spacing from the second housing part so as to form an air cushion between the second housing part and the housing cover and the cover edge portion of the housing cover is supported on the first housing part so as to enclose the second housing part.

Abstract: An electric motor operated impeller has a drive motor having a motor shaft, a stator and a rotor rotated about a rotary axis, an impeller housing having a receiving casing which extends in direction of the rotary axis of the rotor and accommodating the electric drive motor. The receiving casing has a wall against which the stator of the drive motor radially abuts a bottom and an opposite edge. A support supports the shaft of the motor and is provided with throughflow openings for cooling air. The wall of the casing has at least one channel-shaped expansion extending parallel to the rotary axis and formed so that the expansion is open toward the edge of the casing and closed toward the bottom of the casing.

Abstract: A radial blower for producing an air stream which is supplied as a secondary air to a waste gas stream of an internal combustion engine has a spiral housing having a substantially tangentially oriented blower output and accommodating a blower wheel which rotates in the spiral housing about a rotary axis in a rotary plane. The blower output forms with the rotary plane of the blower wheel an acute angle which converges in a flow direction of air. An air guiding chamber is provided with stationary guiding elements, and the blower output is open in the air guiding chamber. An overflow opening extends substantially radially to the rotary axis of the blower wheel. The guiding elements of the guiding chamber deviate an inflowing air substantially radially to the overflow opening. A second spiral housing accommodates a second blower wheel. The overflow opening opens in the central region of the second spiral housing.

Abstract: The muffler for a fan, especially a bypass air fan of an internal combustion engine, has a housing provided with an air outlet opening and an air inlet opening and including a housing pot having a top opening and a flat housing cover at least partially closing the top opening of the housing pot, the air inlet opening being coaxial to the housing axis and advantageously provided in the housing cover, and a damping insert made from a sound absorbing material and being provided with at least one helical or spiral air flow passage providing a connection between the air outlet opening and the air inlet opening so that air can flow through the air inlet opening to the air outlet opening. In one variation the air outlet opening can open radially from the housing pot and the air inlet opening can be provided centrally in a flat housing cover.