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Showing papers by "ebm-papst published in 2011"


Patent
Markus Hirt1
27 Jan 2011
TL;DR: In this paper, an electric motor has a permanent magnet rotor (46) and a device for producing a three-phase sinusoidal current (i202, i204, 1206) for supplying power to the motor.
Abstract: An electric motor has a permanent magnet rotor (46) and a device for producing a three-phase sinusoidal current (i202, i204, 1206) for supplying power to said motor (40), furthermore a microprocessor (95) for carrying out the following steps: while the motor (40) is running with a load which deviates little or not at all from a predefined value, the motor is operated first at a predefined operating voltage (U), and an amplitude of a current flowing to the motor is measured and stored (S106, S108) Subsequently, the amplitude of the voltage supplied to the motor is reduced (S110) Thereupon, an amplitude of the current flow into the motor (40) is measured again and said amplitude is compared (S116) to the amplitude previously stored If it is established that the current flow to the motor has not decreased as a result of the reduction in the amplitude of the voltage, the motor (40) is operated at said current If, however, it is established that the current flowing to the motor has decreased as a result of the reduction in the voltage supplied to the motor (40), the measurements and the comparison are repeated, optionally many times, in order to obtain values for an optimized efficiency

20 citations


Patent
21 Nov 2011
TL;DR: In this article, an electronic control circuit for an electric device, in particular designed as a commutation electric system of an EC motor, having a plurality of power transistors which are controlled in an operating mode for controlling the device is presented.
Abstract: The disclosure relates to an electronic control circuit for an electric device, in particular designed as a commutation electric system of an EC motor, having a plurality of power transistors which are controlled in an operating mode for controlling the device. An additional, similar, non-charged reference transistor in the operating mode of the power transistors is arranged or formed together with the power transistors on a common support or substrate. The circuit also comprises means for applying to the reference transistor and at least one power transistor, respectively one test flow in a test mode for measuring the respective associated saturation voltage and for evaluating saturation tension differences resulting from the measured saturation voltages of the reference transistors and the respective power transistors taking into account the temperature of the support/substrate produced during the measurement as the criterion for an aging process and an expected remaining service life of the power transistors. The disclosure also relates to a method for monitoring power transistors in said type of electronic control circuit with respect to the expected remaining service life thereof.

12 citations


Patent
10 Nov 2011
TL;DR: In this article, an external-rotor motor with a tubular ferromagnetic yoke was designed to serve as a magnetic return path for the external rotor motor during final assembly.
Abstract: A mixed-flow fan features a housing ( 42 ); an impeller ( 43 ) journaled rotatably with respect to the housing, and equipped with fan blades ( 54 ); a generally cylindrical air conduit ( 50 ) defined between the fan housing and the impeller, the fan blades extending into the air conduit in order, during operation, to transport air; an external-rotor motor ( 75 ) having an internal stator ( 100 ) and an external rotor ( 74 ) which includes a tubular ferromagnetic yoke ( 63 ) partly embedded in material of the impeller. A cup-shaped yoke ( 72 ) fits into a central cavity ( 68 ) of the tubular yoke ( 63 ) and accommodates a permanent magnet arrangement ( 66 ) which interacts with the stator. The tubular yoke ( 63 ) and the cup-shaped yoke ( 72 ) together serve as a magnetic return path for the external-rotor motor. The structure minimizes damage during final assembly, and simplifies insertion of balancing weights.

10 citations


Proceedings ArticleDOI
21 Nov 2011
TL;DR: In this paper, a discrete PARETO-optimal magnetization distribution has been identified which promises a higher fundamental PM flux linkage amplitude compared to radial magnetization, but at a significantly lower cogging torque and torque ripple utilizing the balancing of open circuit voltage harmonics.
Abstract: This work relates to external rotor type permanent magnet synchronous machines having surface mounted permanent magnets and two-layer non-overlapping windings. A short review of approaches to reduce fluctuation of forces presented in literature is given. As the reduction is associated in most cases with a negative influence on other important design goals, multi-objective optimizations are applied in conjunction with the finite element analysis yielding PARETO-optimal solutions with different preferences. PARETO-optimal solutions regarding the permanent magnet magnetization distribution and the current profiles minimizing the torque fluctuation of a 12-slot 8-pole machine and the higher frequency radial force harmonics in a 12-slot 10-pole machine are presented and discussed. A discrete PARETO-optimal magnetization distribution has been identified which promises a higher fundamental PM flux linkage amplitude compared to radial magnetization, but at a significantly lower cogging torque and torque ripple utilizing the balancing of open circuit voltage harmonics. Furthermore, it is shown that individual current harmonics affect individual radial force harmonics dominantly. A test setup is proposed and the numerically obtained instantaneous torque and the influence of current harmonics on the radial force amplitudes are verified with good agreement.

10 citations


Patent
16 Jun 2011
TL;DR: In this paper, an electronic commutation control is used for the time offset control of stator coils of the motor of a rotational motor, which produces the magnetic rotating field for a rotor depending on the rotor rotation position.
Abstract: The control circuit (1) has a semiconductor end stage (2) that is controlled by an electronic commutation control (4) through a driver stage (6) for the time offset control of stator coils of the motor (M). The motor produces the magnetic rotating field for a rotor depending on the rotor rotation position. Two redundant stall protection units (10,12) monitor the motor during rotating operation of the rotor. The stall protection unit (10) deactivates driver stage and stall protection unit (12) shuts off the supply voltage for driver stage.

7 citations


Proceedings ArticleDOI
01 Jan 2011
TL;DR: In this article, the development of two small high performance single stage diagonal fans is described and the design objectives and constraints are discussed and the aero/acoustic performance of the new fan is compared to an existing diagonal fan.
Abstract: The development of two small high performance single stage diagonal fans is described. The design objectives and constraints are discussed and the aero-/acoustic performance of the new fan is compared to an existing diagonal fan. For the aerodynamic design, the maximum flow coefficient and the maximum pressure coefficient at stall are prescribed together with geometrical constraints on outer diameter and axial space. The aerodesign is carried out using a through-flow method and 3D CFD. Two design variants are presented, a design with guide vanes for pressure recovery and a variant with struts optimized for low noise. The numerical predictions are compared to experimental data. The agreement between the predicted performance and the experimental data is sufficient for design purposes. Compared to the existing diagonal fan, the new fan shows significant improvements in terms of efficiency, performance and noise without compromising versatility and overall dimensions.Copyright © 2011 by ASME

7 citations


Patent
18 Mar 2011
TL;DR: In this paper, the authors propose a method for assigning an identical start-address as network address to all the ventilators in the system. But the method requires the use of an adjustable network address memory for each ventilator.
Abstract: The method involves providing an adjustable network address memory (9) for each of ventilators (3,4,5) and assigning an identical start-address as network address to all of the ventilators. A serial number queries is sent with a serial number mask which are being sent to the network address. The ventilators unique network addresses are assigned or the serial number mask is modified for serial number queries by using a control unit (1). Independent claims are included for the following: (1) ventilator; and (2) control unit.

6 citations


Patent
Dieter Best1, Werner Müller1
09 Sep 2011
TL;DR: In this paper, a rotor for an electric rotor motor, consisting of a rotor bell with a peripheral wall and at least one one-sided rotor base, was described. But the rotor was not used to enclose a stator.
Abstract: Disclosed is a rotor ( 1 ) for an electric rotor motor, consisting of a rotor bell ( 2 ) with a peripheral wall ( 4 ) and at least one one-sided rotor base ( 6 ) to enclose a stator, in particular as a part of a motor housing with a high IP rating, for example IP54 per DIN/IEC-EN 60034-5. The rotor bell ( 2 ) features a heat sink ( 12 ) with high heat conductivity that extends through the rotor base ( 6 ) in such a way that the motor heat arising on the inside can be removed via the heat sink ( 12 ) through the rotor base ( 6 ) to the outside into the environment. Further, the invention relates to an electric rotor motor, in particular with an encapsulated motor housing with a high IP-protection system, for example IP54 per DIN/IEC-EN 60034-5, consisting of a stator and a rotor ( 1 ) enclosing the stator in an embodiment of the above-described type.

6 citations


Patent
Jens Krotsch1
12 Apr 2011
TL;DR: In this paper, the stator has a radially symmetric iron core with a defined number of stator teeth, which are each adjacent to one another via stator slots and slot openings in the circumferential direction.
Abstract: An electric motor ( 1 ) has a stator ( 2 ) and a radially symmetric, permanent magnet excited rotor ( 4 ) coaxial with the stator ( 2 ). The rotor ( 4 ) rotates relative to the stator ( 2 ) about a common motor axis (X). The stator ( 2 ) has a radially symmetric iron core ( 6 ) with a defined number (N) of stator teeth ( 10 ) which are each adjacent to one another via stator slots ( 8 ) and slot openings ( 8 a ) in the circumferential direction. The rotor ( 4 ) has pole magnets ( 14 ) adjacent to one another. A circumferential gap ( 18 ) is formed radially between the pole magnets ( 14 ) and the stator teeth ( 10 ). Each stator tooth ( 10 ) has on its surface ( 20 ) facing the gap ( 18 ) and adjacent to the slot openings ( 8 a ) on both sides in the circumferential direction a relief-like topographic region ( 22 ) radially enlarging the gap ( 18 ) with least one concave recess ( 24 ) and a smooth profile.

5 citations


Patent
28 Feb 2011
TL;DR: In this article, a blower device for delivering at least one medium, comprising a housing with an inlet and an outlet, a nozzle which is fluidically connected and arranged on the housing such that at least 1 medium can flow there through, wherein the nozzle is designed to effect a negative pressure on the at least 2 medium at least in some sections, and a sensor which is arranged in the effective region of the nozzle and designed to measure at least parameters of the 2 medium which are required to determine the mass of the 3 medium.
Abstract: The invention relates to a blower device for delivering at least one medium, comprising a blower having a housing with an inlet and an outlet, a nozzle which is fluidically connected and arranged on the housing such that at least one medium can flow therethrough, wherein the nozzle is designed to effect a negative pressure on the at least one medium at least in some sections, at least one sensor, wherein the sensor is arranged in the effective region of the nozzle and designed to measure at least parameters of the at least one medium which are required to determine the mass of the at least one medium.

5 citations


Patent
30 Nov 2011
TL;DR: In this paper, a volume compensation element (11) is fixed and embodied elastically in such a way that, in order to compensate for pressure fluctuations occurring in the interior, a variable spatial volume is present as a result of a change in the position of the volume compensated element with respect to the carrier plate.
Abstract: The present invention relates to a housing for accommodating an electronic circuit (4) composed of a plurality of components (5), consisting of a carrier plate (7) and a housing cover (8) with a circumferentially closed wall (9) arranged on the carrier plate (7), and with a covering part (10) arranged on the wall (9) and situated opposite the carrier plate (7). On the carrier plate (7), in an interior enclosed by the housing cover (8) in a pressure-tight manner relative to an external atmosphere, a volume compensation element (11) is fixed and embodied elastically in such a way that, in order to compensate for pressure fluctuations occurring in the interior, a variable spatial volume is present as a result of a change in the position of the volume compensation element (11) with respect to the carrier plate (7). An interspace between the volume compensation element (11) and the carrier plate (7) is connected to the external atmosphere.

Patent
Francisco Rojo Lulic1
25 Feb 2011
TL;DR: In this paper, an external rotor motor with a bearing support tube has been described, where the stator has an internal recess containing a securing ring or disk with inwardly extending tabs, and the tabs slide in the guide grooves, then bend to form barbs which engage into the outer surface of the bearing support tubes.
Abstract: An external rotor motor, suitable for driving a cooling fan, has a structure which facilitates automated assembly with proper angular registration. The rotor has a central shaft which is rotatably supported inside a bearing support tube having a tapered outer surface formed with a circumferential stop and longitudinal guide grooves. An inner stator structure is located radially between the bearing support tube and the rotor. The stator has an internal recess containing a securing ring or disk with inwardly extending tabs. During assembly of the inner stator onto the bearing support tube, the tabs slide in the guide grooves, then bend to form barbs which engage into the outer surface of the bearing support tube, thereby securing the stator on the bearing support tube in a predefined angular orientation. The circumferential stop assures insertion of the bearing support tube to the correct depth.

Patent
28 Feb 2011
TL;DR: Geblasevorrichtung zur Forderung mindestens eines Mediums umfassend ein Geblases mit Gehause mit einem Einlass and einem Auslass, eine Duse, die derart stromungsverbunden an dem Gehause angeordnet ist, dass sie von dem mindestins einen Medium durchstrombar ist.
Abstract: Geblasevorrichtung zur Forderung mindestens eines Mediums umfassend ein Geblase mit Gehause mit einem Einlass und einem Auslass, eine Duse, die derart stromungsverbunden an dem Gehause angeordnet ist, dass sie von dem mindestens einen Medium durchstrombar ist, wobei die Duse ausgebildet ist, zumindest abschnittsweise einen Unterdruck des mindestens einen Mediums zu bewirken, mindestens einen Sensor, wobei der Sensor im Wirkungsbereich der Duse angeordnet und ausgebildet ist, zumindest Parameter des mindestens einen Mediums zu messen, die zur Bestimmung der Masse des mindestens einen Mediums notig sind.

Patent
Christian Hammel1, Erhard Gruber1, Christian Haag1, Oliver Haaf1, Michael Strehle1 
09 Mar 2011
TL;DR: In this paper, a radial fan wheel assembly consisting of a circular bottom plate and a circular cover disk with a central inflow opening was described, where at least one of the two disks (2, 3) in the wafer edge portion is at least a counterweight (13), and in the intermediate space between the vanes in the outer edge region of the cover disk and / or the bottom plate (2) are at least on one side in the disc surface pocket-shaped recesses.
Abstract: The present invention relates to a radial fan wheel assembly consisting of a circular bottom plate (2) and a circular cover plate (3) with a central inflow opening (4) and between the bottom plate (2) and the cover disc (3) extending vanes (6 ). On at least one of the two disks (2, 3) in the wafer edge portion is at least one counterweight (13). In the intermediate space between the vanes (6) in the outer edge region of the cover disk (3) and / or the bottom plate (2) are at least on one side in the disc surface pocket-shaped recesses (9). In the region of at least one of the pocket-shaped recesses (9) is at least one counterweight (13).

Patent
12 Jul 2011
TL;DR: The ring has a circular connecting piece formed on a supporting frame that is assembled from a set of frame elements by form and force-fitting connecting elements as mentioned in this paper, and an axial fan is arranged in the connecting piece.
Abstract: The ring has a circular connecting piece (2) formed on a supporting frame (1) that is assembled from a set of frame elements (6) by form and force-fitting connecting elements (3) An axial fan is arranged in the connecting piece, which is formed of circular segments (22) to be circumferentially arranged one after the other The segments are connected to each other and with the frame by form and force-fitting or material-bonded connections or by other connecting elements The frame includes a rectangular quadratic circumferential contour with four corners and a center opening

Patent
25 May 2011
TL;DR: In this paper, an air-guiding member is provided in the region of the air inlet and by means of which, during operation, the air passing from the air-inlet (78) is conducted to the fan impeller (20) and which, at least in a magnetically active return path region (72) of the drive motor, is formed from a ferromagnetic material and serves there as a magnetic return path for the stator; stator pole shoes (50, 52, 54, 56, 58, 60) which are arranged on the
Abstract: A sensor fan (18) has a brushless drive motor (40, 50, 52, 54, 56, 58, 60, 66, 68) having a stator (50, 52, 54, 56, 58, 60, 66, 68) and having a permanent-magnetic rotor (40); a fan impeller (20) which is drive-connected to said rotor (40); an air inlet (78) through which the air flows into the sensor fan (18) during operation and on which can be mounted at least one sensor element (80) for detecting at least one characteristic of the air transported through the sensor fan (18); an air-guiding member (74) which is provided in the region of the air inlet (78) and by means of which, during operation, the air passing from the air inlet (78) is conducted to the fan impeller (20) and which, at least in a magnetically active return path region (72) of the drive motor, is formed from a ferromagnetic material and serves there as a magnetic return path for the stator; stator pole shoes (50, 52, 54, 58, 60) which are separated from the rotor (40) in each case by a magnetically active air gap (50B, 52B, 64B, 56B, 58B, 60B); stator pole cores (66) which extend in each case from a stator pole shoe (50, 52, 54, 56, 58, 60) to the magnetically active return path region (72) of the air-guiding member (74); stator windings (68) which are arranged on the stator pole cores (66) and which are separated from one another in the circumferential direction by radial passages (81), through which passages (81) the air conveyed by the fan impeller (20) can flow during operation.

Patent
Paul Layes1, Andreas Kienzler1
12 May 2011
TL;DR: In this article, an injection molded structure made of plastic and provided at the core of a stator motor is used to support the rotor shaft. But the rotor is arranged at an outer side (129) of the core such that a magnetically active air gap is formed between the rotor and the outer side of the stator.
Abstract: The motor (100) has an inner stator (110) with a laminated core (120) that includes a central inner recess (125). Bearing arrangements (130, 135) are arranged in the recess. An external rotor (150) is provided with a permanent magnet arrangement (140) that is fastened with a rotor shaft (160). The rotor is arranged at an outer side (129) of the core such that a magnetically active air gap (170) is formed between the rotor and the outer side of the core. A base part (180) is connected with supporting legs (121, 122) of the core, where the supporting legs support the stator at the base part. The motor has an injection molded structure that is made of plastic and provided at the core.

Patent
Thomas Wagner1, Francisco Rojo1
25 Feb 2011
TL;DR: In this paper, an electronically commutated external rotor motor is used to drive a fan with a permanent magnetically acting air gap, where the rotor is separated from the internal stator by a magnetically-acting air gap.
Abstract: A fan has an electronically commutated external rotor motor which is used to drive it. This motor has an internal stator (20) with a laminated stator core (64) and with a winding arrangement (66; 164, 166, 168, 170) associated with it. The internal stator has a central recess (149) for bearing a shaft (42). The fan furthermore has a permanent-magnet rotor (28), which is separated from the internal stator (20) by a magnetically acting air gap (99), is provided on its outside with fan blades (32) and has a shaft (42) which is borne in the central recess (149) in the internal stator (20). A plastic coating (56, 58) is also provided, and extends into the central recess (149) in the internal stator (20), where it forms a bearing tube for holding bearing elements (48, 50), for bearing the shaft (42), furthermore having a wall element (62), which is formed integrally with this plastic coating (56, 58), for a cavity (108) for holding electrical components (112) of the motor, which wall element (62) is provided on that side of the laminated stator core (64) which faces away from the rotor (28), and a fan housing (24), which is integrally connected by connecting elements (134, 136) to the wall element (62) of the cavity (108) and, together with the rotor (28), forms an air passage channel (142), into which the fan blades (32) project.

Patent
24 Nov 2011
TL;DR: In this paper, the authors proposed a method for triggering a semiconductor switch of a bridge inverter circuit, which is triggered by a variable control current (i G (t)) for switching, said control current being predefined as a function of the time profile of a voltage (u FD (t) measured at the freewheeling element (FD) and/or as a frequency of the voltage(u DS (t)).
Abstract: The present invention relates to an electronic circuit (1), comprising at least one semiconductor switch (S) that is mounted with its switching path (D-S) in series with an inductive load (2) that is to be triggered, and at least one freewheeling element (FD) that interacts with the semiconductor switch (S) during switching phases and is also mounted in series with the load (2). A control unit controls a control connection (G) of the semiconductor switch (S) with a variable control current (i G (t)) as a function of the time profile of a voltage (u FD (t)) measured at the freewheeling element (FD) and/or as a function of the time profile of the voltage (u DS (t)) measured at the switching path (D-S). The invention further relates to a method for triggering a semiconductor switch (S) of such a circuit (1), which is triggered by a variable control current (i G (t)) for switching, said control current being predefined as a function of the time profile of a voltage (u FD (t)) measured at the freewheeling element (FD) and/or as a function of the time profile of the voltage (u DS (t)) measured at the switching path (D-S). The electronic circuit according to the invention is advantageously used for triggering semiconductor switches of a bridge inverter circuit (10), in particular for operating an EC motor.

Patent
Harald Schmid1
27 Apr 2011

Patent
Konstantin Dornhof1
14 Nov 2011
TL;DR: In this article, an electronically commutated motor (ECM) often employs a Hall sensor for reliable operation, even when the Hall sensor is omitted from a motor having a plurality of stator winding phases and a permanent magnet rotor.
Abstract: An electronically commutated motor (ECM) often employs a Hall sensor for reliable operation. Even when a Hall sensor is omitted from a motor having a plurality of stator winding phases ( 24, 26 ) and a permanent-magnet rotor ( 22 ), one can reliably detect direction of rotation of the rotor by the steps of: (a) differentiating a voltage profile obtained by sampling either (1) induced voltage in a presently currentless phase winding or (2) voltage drop at a transistor, through which current is flowing to a presently energized phase winding, and (b) using such a differentiated signal (du — 24 ″/dt, du — 26 ″/dt) to control current flow in an associated phase winding. In this manner, one obtains reliable commutation, even if the motor is spatially separated from its commutation electronics.

Patent
Markus Hirt1
27 Jan 2011
TL;DR: In this article, an Elektromotor (40) bei einer Last lauft, die von einem vorgegebenen Betriebsspannung (U) betrieben, and eine Amplitude eines zum Motor fliesenden Stromes wird gemessen and gespeichert (S106, S108).
Abstract: Ein Elektromotor hat einen permanentmagnetischen Rotor (46) und eine Vorrichtung zur Erzeugung eines dreiphasigen sinusformigen Stromes (i202, i204, i206) zur Stromversorgung dieses Motors (40), ferner einen Mikroprozessor (95) zur Ausfuhrung folgender Schritte: Wahrend der Motor (40) bei einer Last lauft, die von einem vorgegebenen Wert wenig oder gar nicht abweicht, wird er zunachst bei einer vorgegebenen Betriebsspannung (U) betrieben, und eine Amplitude eines zum Motor fliesenden Stromes wird gemessen und gespeichert (S106, S108). Danach wird die Amplitude der dem Motor zugefuhrten Spannung reduziert (S110). Darauf folgend wird erneut eine Amplitude des zum Motor (40) fliesenden Stromes gemessen, und diese Amplitude wird mit der zuvor gespeicherten Amplitude verglichen (S116). Falls dabei festgestellt wird, dass der zum Motor fliesende Strom durch die Reduzierung der Spannungsamplitude nicht abgenommen hat, wird der Motor (40) bei diesem Strom betrieben. Falls aber festgestellt wird, dass der zum Motor fliesende Strom als Folge der Reduzierung der dem Motor (40) zugefuhrten Spannung abgenommen hat, werden die Messungen und der Vergleich, ggf. mehrfach, wiederholt, um Werte fur einen optimierten Wirkungsgrad zu erhalten.

Patent
Christian Hammel1, Erhard Gruber1, Oliver Haaf1, Christian Haag1, Michael Strehle1 
15 Sep 2011
TL;DR: The vorliegende Erfindung betrifft eine Radial-Lufterrad-Anordnung, bestehend aus einer kreisformigen Bodenscheibe (2) and einer Kreis-formigen Deckscheibe(3) with einer mittigen Einstromoffnung (4) as discussed by the authors.
Abstract: Die vorliegende Erfindung betrifft eine Radial-Lufterrad-Anordnung, bestehend aus einer kreisformigen Bodenscheibe (2) und einer kreisformigen Deckscheibe (3) mit einer mittigen Einstromoffnung (4) sowie zwischen der Bodenscheibe (2) und der Deckscheibe (3) verlaufenden Radschaufeln (6). Auf mindestens einer der beiden Scheiben (2, 3) im Scheibenrandbereich ist mindestens ein Ausgleichgewicht (13) befestigt. Im Zwischenraum zwischen den Radschaufeln (6) im auseren Randbereich der Deckscheibe (3) und/oder der Bodenscheibe (2) sind zumindest einseitig in der Scheibenoberflache taschenformige Vertiefungen (9) ausgebildet. Im Bereich mindestens einer der taschenformigen Vertiefungen (9) ist zumindest ein Ausgleichgewicht (13) befestigt.

Patent
Dominik Seyfried1
12 May 2011
TL;DR: In this paper, the arrangement has an air guide channel and a fan device with a fan housing, where the air-guide channel is extended through the fan housing and damping elements made of elastomeric materials are arranged at corners of the mounting flange.
Abstract: The arrangement has an air guide channel and a fan device (30) that is provided with a fan housing, where the air guide channel is extended through the housing. A rectangular mounting flange (32) is formed at an end of an outer wall of the air guide channel for fastening the fan housing. Damping elements made of elastomeric materials are arranged at corners (52) of the mounting flange. Snap-on hooks are engaged in a fastening frame for forming a structure-borne sound degenerating mechanical connection between the fan device and the fastening frame.

Patent
Konstantin Dornhof1
14 Nov 2011
TL;DR: In this article, an electronically commutated motor (ECM) often employs a Hall sensor for reliable operation, even when the Hall sensor is omitted from a motor having a plurality of stator winding phases and a permanent magnet rotor.
Abstract: An electronically commutated motor (ECM) often employs a Hall sensor for reliable operation. Even when a Hall sensor is omitted from a motor having a plurality of stator winding phases ( 24, 26 ) and a permanent-magnet rotor ( 22 ), one can reliably detect direction of rotation of the rotor by the steps of: (a) differentiating a voltage profile obtained by sampling either (1) induced voltage in a presently currentless phase winding or (2) voltage drop at a transistor, through which current is flowing to a presently energized phase winding, and (b) using such a differentiated signal (du — 24 ″/dt, du — 26 ″/dt) to control current flow in an associated phase winding. In this manner, one obtains reliable commutation, even if the motor is spatially separated from its commutation electronics.

Patent
Oliver Haaf1, Erhard Gruber1
25 Oct 2011
TL;DR: In this article, an axial ventilator wheel with a hollow cylindrical hub and a plurality of axial blades is described, in which the hub is shortened with respect to the axial hub length at its inflow side in a peripheral direction between the blade bases of the adjacent blades by means of recesses around the edges.
Abstract: The invention relates to an axial ventilator wheel (1), comprising a wheel body (2) having a hollow cylindrical hub (4) and a plurality of ventilator blades (6) which are distributed around the circumference and connected to the hub (4). Each ventilator blade (6) extends in an axial direction in the area of a blade base (8) connected to the hub (4), and is inclined in a peripheral direction between an inflow side (10) and an outflow side (12) of the hub (4). The hub (4) is shortened with respect to the axial hub length thereof at its inflow side (10) in a peripheral direction between the blade bases (8) of the adjacent ventilator blades (6), respectively, by means of recesses (16) around the edges.

Patent
Hirt Markus1
27 Jan 2011
TL;DR: In this article, an elektrischen kommutierter motor (250) is vermessungen in an unbestromten Zustand wahrend eines ersten Durchlaufens des vorgegebenen Segments.
Abstract: Elektronisch kommutierter Motor (250), welcher aufweist:einen Stator (210), welchem eine Statorwicklungsanordnung (212, 214) zugeordnet ist;einen Rotor (220), welcher in Wechselwirkung mit dem Stator (210) steht;eine Vorrichtung (215) zur Bestromung der Statorwicklungsanordnung (212, 214) gemas einem vorgegebenen Bestromungsmuster (460), welches einem ausgewahlten Betriebszustand des Motors (250) zugeordnet ist;einen Sensor (230) zur Erzeugung eines elektrischen Bilds (410) mindestens eines vorgegebenen Segments (205) einer vollstandigen mechanischen Umdrehung (405) des Rotors (220),wobei bei einer ersten Vermessung des Motors (250) im unbestromten Zustand wahrend eines ersten Durchlaufens des vorgegebenen Segments (205) ein erstes elektrisches Bild (412; 512; 612; 712) dieses Segments (205) bestimmbar ist,und bei einer zweiten Vermessung des Motors (250) im bestromten Zustand nach Ablauf eines n-fachen einer vollstandigen mechanischen Umdrehung des Rotors (220), gemessen ab dem Beginn des ersten Durchlaufs des vorgegebenen Segments (205), wobei n = 1, 2, 3, etc. ist, ein zweites elektrisches Bild (416; 516; 616; 716) dieses Segments (205) bestimmbar ist;eine Auswerteeinheit (240), welche zur Ausfuhrung folgender Schritte ausgebildet ist:a) auf der Basis des ersten Bilds (412; 512; 612; 712) wird eine erste drehzahlrelevante Zeitspanne (T1) bestimmt;b) auf der Basis des zweiten Bilds (416; 516; 616; 716) wird eine zweite drehzahlrelevante Zeitspanne (T2) bestimmt;c) das erste Bild (412; 512; 612; 712) wird mit dem zweiten Bild (416; 516; 616; 716) verglichen, um eine Information uber einen tatsachlichen Betriebszustand des Motors (250) zu ermitteln, indem die erste und zweite Zeitspanne (T1, T2) miteinander verglichen werden, um eine Information uber die augenblickliche Drehrichtung des Motors (250) zu erhalten ohne Messung der induzierten EMK, wobeid) fur den Fall, dass die erste Zeitspanne (T1) groser ist als die zweite Zeitspanne (T2), wird die erste Drehrichtung (DIR_s=1) als augenblickliche Drehrichtung (DIR_n) bestimmt und fur den Fall, dass die erste Zeitspanne (T1) kleiner oder gleich der zweiten Zeitspanne (T2) ist, wird eine zweite, zur ersten Drehrichtung (DIR_s=1) entgegen gesetzte Drehrichtung (DIR_s=2) als augenblickliche Drehrichtung (DIR_n) bestimmt, sofern eine erste Drehrichtung (DIR_s=1) als ausgewahlter Betriebszustand vorgegeben ist unde) fur den Fall, dass die erste Zeitspanne (T1) groser als die zweite Zeitspanne (T2) ist, wird die zweite Drehrichtung (DIR_s=2) als augenblickliche Drehrichtung (DIR_n) bestimmt und fur den Fall, dass die erste Zeitspanne (T1) kleiner oder gleich der zweiten Zeitspanne (T2) ist, wird die erste Drehrichtung (DIR_s=1) als augenblickliche Drehrichtung (DIR_n) bestimmt, sofern die zweite Drehrichtung (DIR_s=2) als ausgewahlter Betriebszustand vorgegeben ist.

Patent
Rudolf Tungl1
22 Jun 2011
TL;DR: In this article, a mixing device for premixing combustion air and gas, having a gas regulating device and a gas outlet and a nozzle, where a gas inlet is provided on the nozzle or on a bridging element disposed on a nozzle.
Abstract: The invention relates to a mixing device for premixing combustion air and gas, having a gas regulating device and a gas outlet and a nozzle, wherein a gas inlet is provided on the nozzle or on a bridging element disposed on the nozzle, and the gas path from the gas outlet to the gas inlet is sealed off by a gasket extending from the gas outlet to the gas inlet.


Patent
Wei Shang1
20 Oct 2011
TL;DR: In this article, a system for controlling a motor is presented, which includes a sensor for sensing position information of a rotor of the motor and a processor for receiving the sensed signal from the sensor and estimating an electrical angle on the basis of the sensed signals.
Abstract: A system for controlling a motor is provided. The system for controlling the motor includes a sensor for sensing position information of a rotor of the motor, a processor for receiving the sensed signal from the sensor and estimating an electrical angle on the basis of the sensed signal, and a control signal generating module for generating a control signal used to control the operation of the motor based on the electrical angle. The system can obtain the necessary control signal for controlling the motor only by one sensor, thereby reducing the complexity of installation of the sensors in the motor and also saving the cost.