WO2018108492A1

WO2018108492A1 - Electric drive motor and domestic appliance or motor module system containing same

Info

Publication number: WO2018108492A1
Application number: PCT/EP2017/080407
Authority: WO
Inventors: Torsten Böttger; Joachim Seubert; Axel Walter
Original assignee: BSH Hausgeräte GmbH
Priority date: 2016-12-15
Filing date: 2017-11-24
Publication date: 2018-06-21
Also published as: DE102016225105A1

Abstract

The invention relates to an electric drive motor comprising a stator with teeth and grooves, and a permanent magnet rotor (1) that has a motor shaft and a laminated core (2) which is seated on said motor shaft and has at least a number of pockets (5) that corresponds to the number of poles (4) of the permanent magnet rotor (1), with a permanent magnet (6) being positioned in the radial direction in each pocket, said permanent magnets (6) being distributed with alternating polarity in the circumferential direction of the permanent magnet rotor (1) and being magnetised in the tangential direction such that a magnetic flux proceeding from each permanent magnet (6) runs in the tangential direction of the permanent magnet rotor (1), and the permanent magnets (6) extend in the axial direction of the permanent magnet rotor (1) beyond the laminated core (2), wherein a segment (11) of the laminated core (2) is disposed between each set of adjacent pockets (5) and designed to concentrate the magnetic flux of the respective permanent magnets (6) in an air gap (7) between the stator and said permanent magnet rotor (1), the laminated core (2) forming a web part (8) extending in the axial direction of the permanent magnet rotor (1), over each permanent magnet (6) respectively on the side of the air gap (7), and said web part (8) interconnecting two segments (11) of the laminated core (2) and comprising web elements (9) and web recesses (10). The invention also relates to a domestic appliance or motor module system containing such a drive motor.

Description

ELECTRIC DRIVEN MOTOR AND THE HOUSEHOLD DEVICE CONTAINING THEREOF. MOTOR KIT

The invention relates to an electric drive motor and a motor kit containing this electric drive motor and a household appliance containing this electric drive motor. More particularly, the invention relates to an electric drive motor comprising a stator with teeth and grooves and a permanent magnet rotor having a motor shaft and a laminated core seated on the motor shaft having at least one of the number of poles of the permanent magnet rotor corresponding number of pockets in which in radial Direction of a permanent magnet is arranged, the permanent magnets distributed in the circumferential direction of the permanent magnet rotor with alternating polarity and magnetized in the tangential direction, so that a outgoing of the respective permanent magnet magnetic flux in the tangential direction of the permanent magnet rotor, and the permanent magnet in the axial direction of the Rotor extend beyond the laminated core, and wherein between adjacent pockets each have a segment of the laminated core is arranged, which is formed, the magnetic flux of the respective permanent magnets in a Concentrate m air gap between the stator and the permanent magnet rotor, wherein the laminated core on each of a permanent magnet on the side of the air gap forms a extending in the axial direction of the permanent magnet rotor web portion which connects two segments of the laminated core together, and this drive motor containing household appliances and motor kit. Electric drive motors, in particular BLDC motors, are frequently used in household appliances. It is desirable in this case for the electric drive motors used to cover a defined power or rotational speed torque range. This can be achieved by providing a suitable number of variants, for example a BLDC motor in the form of a so-called modular system. It is desirable in view of the simplicity and cost of providing the variants that on the one hand, the number of variants is not excessive and on the other hand, the distinction of the variants by a limited set of Design features or components takes place. All other components should preferably remain unchanged as so-called equal parts.

As far as the configuration of an electric drive motor for a domestic appliance is concerned, it is desirable to have important application properties such as power density, especially with regard to the provision of variants for a defined power or rotational speed torque range as well as widespread use in various domestic appliances as well as the noise development can be improved. In the prior art, various electric drive motors are known, which can be used in particular in household appliances.

The publication DE 10 2010 061 784 A1 describes a spoke rotor for an electric machine with a rotor shaft rotatable about a rotor axis, with a base body, which is arranged concentrically around the rotor shaft, and with at least two permanent magnets, each arranged in a recess of the main body like a spoke are. The spoke rotor has a connecting sleeve comprising an inner ring and a first frame surface, wherein the frame surface is arranged transversely to the rotor shaft and the inner ring on the frame surface, and wherein the inner ring concentrically extends around the rotor shaft and forms a bearing for the permanent magnets. The main body consists of several sectors, which are spaced from each other, that between them a recess is formed, in which permanent magnets are used. The sectors are connected to each other in particular via connecting webs on their side facing away from a rotor shaft. In addition, they have in the axial direction of the rotor axis extending holding webs, against which the permanent magnets abut on their side facing away from the rotor shaft. As a result, the permanent magnets are held in the radial direction on the inside by the inner ring and on the outside by the connecting webs and / or retaining webs. WO 2016/026831 A1 describes a rotor for an electric machine of a household appliance, with a plurality of permanent magnets, which are arranged distributed in the circumferential direction of the rotor with alternating polarity and magnetized in the tangential direction, and a rotor package, which consists of a magnetically conductive material is formed, wherein the rotor core has a plurality of through holes, which extend in the axial direction of the rotor and which are arranged distributed in the circumferential direction of the rotor spaced from each other, wherein in the through holes, the permanent magnets are arranged such that one of the respective Permanent magnet outgoing magnetic flux in the tangential direction of the rotor extends, wherein between adjacent passage openings in each case a segment of the rotor core is formed, which is designed to concentrate the magnetic flux of the respective permanent magnets in an air gap of the electric machine, and wherein the permanent magnets compared to the rotor core have a greater extent in the axial direction of the rotor. The web can have a small width, which can be achieved that the magnetic flux through the web is as low as possible.

The publication WO 2014/082839 A2 describes a permanent magnetic Spoke rotor which forms the rotating part of an electric motor inside a stator and has an air gap between the inner surface of the stator and itself, comprising a cylindrical ferromagnetic core, a shaft, which the A rotation axis thereof, a hub disposed at the center of the core and having a shaft hole supporting the shaft, more than one pole segment disposed around the hub, more than one magnetic recess between the pole segments, more than one magnet which are arranged in the magnetic recesses and extend outward in the radial direction, and two end rings of a non-magnetic material, which are produced on the front and rear planar surface of the core by means of an injection molding process. The magnets whose length in the axial direction is greater than the length of the magnetic recesses are embedded in the end rings.

The publication DE 10 2008 007 565 A1 describes a permanent magnet-excited electric machine for driving a component of a domestic appliance, with a rotor and a stator, wherein the rotor and / or the stator has a plurality of stacked and interconnected plate-like sheet metal parts and the modular structure of Machine at least the rotor and / or the stator depending on the number of sheet metal parts is modular buildable. In one embodiment, the stator is formed from a plurality of sheet metal parts designed in the axial direction of the stator, and the Sheet metal parts have an outer dimension (d) of less than or equal to 100 mm. In a further preferred embodiment of the electric machine, a sheet metal part of a stator is circular and has radially oriented teeth which are straight at their side facing the center. The publication EP 2 568 578 A2 describes a motor comprising: a stator having a plurality of stator cores arranged in a circumferential direction of the motor and a winding wound around the stator cores; and a rotor disposed on an inner side of the plurality of stator cores, wherein the rotor includes: a sleeve forming a well hole; a plurality of rotor cores arranged in a circumferential direction of the rotor; and a plurality of permanent magnets disposed between the rotor cores, wherein the plurality of permanent magnets form an internal space with respect to the sleeve while being spaced from the sleeve; and a plurality of supporting protrusions extending from the sleeve in an outer radial direction of the sleeve to support the plurality of permanent magnets while corresponding to the plurality of permanent magnets, respectively. The engine can be used in particular in a washing machine, a dryer and an air conditioner; and also used in an electric vehicle that requires a small, high power engine. The publication EP 2 696 470 A2 describes a rotor and a manufacturing method for a rotor, the rotor having a plurality of permanent magnets arranged in a circumferential direction, and a laminated core in which a plurality of thin plate cores are laminated in an axial direction and a part formed by injection molding. A description is given in particular of a production method which has been improved with regard to reducing the injection pressure on the rotor, and the rotor obtained thereby.

Against this background, it was an object of the present invention to provide an electric drive motor, in particular a brushless DC motor, with an improved permanent magnet rotor. In addition, a motor kit and a household appliance to be provided, which each contain this electric drive motor. The solution of this object is achieved according to this invention by an electric drive motor and a motor modular system containing this electric drive motor and a household appliance containing this electric drive motor with the features of the corresponding independent claims. Preferred embodiments of the electric drive motor according to the invention are listed in the dependent claims.

Preferred embodiments of the electric drive motor according to the invention correspond to preferred embodiments of the motor construction kit according to the invention and of the household appliance according to the invention, even if this is not explicitly stated herein.

The invention thus relates to an electric drive motor comprising a stator with teeth and grooves, and a permanent magnet rotor having a motor shaft and a laminated core seated on the motor shaft having at least one of the number of poles of the permanent magnet rotor corresponding number of pockets in which arranged in the radial direction in each case a permanent magnet, the permanent magnets distributed in the circumferential direction of the permanent magnet rotor with alternating polarity and are magnetized in the tangential direction, so that an outgoing from the respective permanent magnet magnetic flux in the tangential direction of the permanent magnet rotor, and the permanent magnets in the axial Direction of the permanent magnet rotor extend beyond the laminated core, and wherein between adjacent pockets each have a segment of the laminated core is arranged, which is formed, the magnetic flux of the respective permanent Concentrate magnets in an air gap between the stator and the permanent magnet rotor, wherein the laminated core on each of a permanent magnet on the side of the air gap forms a extending in the axial direction of the permanent magnet rotor web portion which connects two segments of the laminated core together, and wherein the web portion has web elements and web recesses ,

In a preferred embodiment of the electric drive motor, the web recesses in the tangential direction each have a same width b _gap . Preferably, the width is b _gap by means of the formula ^* calculated bgap = a _gap / 180 * TT r (I) wherein R is an outer radius of the permanent magnet rotor and a _gap by means of the formula II

a _Bap / = 360 (2p ^* N / gcd) / 2 (II) is calculated, where 2p is the number of poles, N is the number of slots in the stator, and gcd is the largest common divisor of the two. According to the invention, it is preferred that the laminated core of the permanent magnet rotor is formed from a stack of several individual sheets. In this case, the web recesses preferably have a length l _gap in the axial direction of the permanent magnet rotor, which is an integer multiple of a thickness d of a single sheet.

In a particularly preferred embodiment of the electric drive motor according to the invention, the web recesses are formed by a stack of open individual sheets and the web elements by closed individual sheets. The term "open individual sheets" stands for individual sheets with open pocket cutouts and the term "closed single sheets" for single sheets with a continuous web. Preferably, the proportion of closed individual sheets, based on the sum of open and closed individual sheets, is in the range of 5 to 20%, more preferably in the range of 10 to 15%. According to the invention, moreover, an electric drive motor is preferred in which a spring device is designed to fix the permanent magnets inserted into the pockets in each case radially outwardly biased within the pockets, wherein the spring device is formed by one or more, in each one of the Bags protruding elastic lugs and each pocket motorwellenfern has a stop device which is fixed to the laminated core and against which the permanent magnet used in each case in one of the pockets by the one or more lugs of the pocket in question is pressed spring biased. Here, the laminated core is preferably formed from a stack of individual sheets and the spring device, in particular the one or more elastic lugs are formed by inwardly projecting edge portions of window cutouts of the individual sheets.

Preferably, the laminated core contains individual sheets which are designed as closed individual sheets, i. Individual sheets are formed with a continuous web, in which an elastic nose of a spring device are formed by inwardly projecting edge portions of window sections of the individual sheets.

For optimum fixation of the permanent magnets, the permanent magnets inserted in the pockets of the laminated core are preferably encapsulated in the electric drive motor by plastic.

The outer contour of the permanent magnet rotor can have different shapes. However, it has been found that a particularly quiet running electric drive motor is obtained when the outer contour of the permanent magnet rotor is circular.

The electric drive motor generally has a fixed outer stator and a rotatably mounted inner rotor. The permanent magnet rotor has a plurality of poles, in particular four, six, eight or more poles. Each permanent magnet of the permanent magnet rotor is assigned a pocket in the usually used laminated core. In each one of these pockets, a single permanent magnet is used and fixed in particular against slipping. Usually, all permanent magnets of the permanent magnet rotor are identical. Each permanent magnet may have a cuboid shape. In this case, the two opposite largest boundary surfaces of the permanent magnet may be aligned in the circumferential direction, with laterally smaller boundary surfaces forming the poles of the magnets. The permanent magnets are distributed uniformly over the circumference of the Pemanentmagnetenrotors. Each pocket may have a shape corresponding to the shape of the permanent magnets, wherein the pocket is slightly larger, so that in each case a single permanent magnet can be inserted into a pocket. The generally used laminated core of the permanent magnet rotor is of several, in particular formed punched sheet metal blanks, which are congruent stacked and connected together to form a compact package. The laminated core can be made by stamping so far. The congruent stacked sheets can, for example, by welding, riveting, staples or just Stanzbzw. Bonding be connected.

The permanent magnets may, for example, have a large, substantially rectangular front boundary surface pointing in the circumferential direction in the circumferential direction and having an opposite, equally sized, substantially rectangular rear boundary surface pointing in the circumferential direction counter to the direction of rotation. An inner narrow boundary surface faces the rotor shaft and an opposite outer narrow boundary surface forms a magnetic pole of the rotor. All edges of the cuboid permanent magnet can be provided with a chamfer or be rounded. The present in embodiments of the invention spring device can in principle be formed from one part, but also formed from several parts. The spring device biases each individual permanent magnet within its respective pocket into a radially outermost position as far as possible. In this case, the permanent magnet rotor on each pocket have a radially outwardmost possible stop, against which the respective inserted in his pocket permanent magnet is pressed by the spring device. All stops are preferably on the same diameter or radius, so that all permanent magnets are positioned by the spring device on the same outer diameter or radius. This ensures that all permanent magnets, i. all poles of the permanent magnet rotor, produce the same magnetic effect in the annular air gap of the electric drive motor.

Advantageously, a spring device or the tongues or lugs contained therein serve to temporarily fix the permanent magnets inserted into the pockets during manufacture and / or assembly of the permanent magnet rotor when the permanent magnets inserted into the pockets by a molding of the laminated core with a Plastic be finally fixed by the hardened plastic in their positions. Such a temporary fixation in the pockets used permanent magnets by the spring device or by the tongues prevents the permanent magnets are moved in the pockets or even fall out completely when the permanent magnet rotor, in particular the laminated core, is moved during manufacture or pre-heated before encapsulation with plastic, before the still not overmolded permanent magnet rotor is inserted into the injection mold. Also, the spring device or the tongues or lugs inserted therein can prevent the permanent magnets inserted into the pockets from being displaced by the liquid plastic flow during the insert molding process. The spring-biasing action of the spring device can therefore optionally be omitted after encapsulation with plastic. If the permanent magnets are not encapsulated with plastic, on the other hand, the spring-biasing action of the spring device should always be maintained, not only during the manufacture and / or assembly of the permanent magnet rotor, but also during operation of the electric drive motor. The optionally used spring device can be formed by one or more, each in one of the pockets projecting elastic tongues, each tongue has a tongue base portion which is fixed motor shaft close to the laminated core, a tongue tip portion projects in the radial direction of the motor shaft pioneering into the bag and each pocket motor shaft remote has a stop device which is fixed to the laminated core and against which the permanent magnet respectively inserted in one of the pockets is pressed spring-biased by the one or more tongues of the pocket in question.

The tongues can thus extend radially outwards, at least substantially, starting from the motor shaft-near boundary surfaces of the pockets. That is, the tongues protrude radially into the pockets starting from the motor shaft near boundary surfaces of the pockets. If the permanent magnets are not yet inserted in the pockets, the tongues are relaxed because they have no spring force stored in them yet. Now, if the permanent magnets in the axial direction, ie in a direction parallel to the motor shaft, placed in the pockets, the permanent magnets press the tongues to the side. The tongues bend to avoid the permanent magnet and a spring force is stored in the tongues. Are the permanent magnets completely in the pockets, then the tongue tip portions of the tongues are elastically biased to the motor shaft near narrow boundary surfaces of the permanent magnets and press the permanent magnets in the radial direction to the outside. In each pocket, one or more tongues may be provided. The stop device can be formed by at least one stop surface, at least one stop web or at least one stop edge in the pockets of the laminated core.

The laminated core of the permanent magnet rotor can be formed from a stack of several individual sheets, which has a number of poles of the permanent magnet rotor corresponding number of window sections, which form the pockets in which the permanent magnets are inserted, in the stacked state of the laminated core, wherein the spring device, in particular the one or more tongues are formed by inwardly projecting edge portions of the window cutouts of the individual sheets of the laminated core.

The window sections thus generally each have an inner edge portion, wherein the stacked edge portions form the side walls of the pockets of the laminated core in the stacked state of the individual sheets. The window cutouts have a contour that substantially corresponds to the cross-sectional contour of the permanent magnets, in particular only slightly larger than the cross-sectional contour of the permanent magnets corresponds, in particular only slightly larger than the cross-sectional contour of the permanent magnets. The permanent magnets can therefore be easily inserted into the pockets but have no great play in the pockets. The spring device, in particular the one or more tongues, in the embodiment in which the inwardly projecting edge portions of the window cutouts of the individual sheets of the laminated core are formed in this respect formed integrally with the respective single sheet. For realizing the invention, individual sheets may be provided which have no spring devices, in particular no tongues. These can in particular form a gap in the web. In addition, for the realization of the invention, individual sheets may be provided which have spring devices, in particular tongues. A stack of a laminated core can be formed by single plates with tongues and by individual packets without tongues. It can as Individual sheets with tongues and individual sheets without tongues be stacked alternately, whereby several individual sheets without tongues can be stacked directly consecutively and can connect to such a group one or, in principle, several individual sheets with tongues. Preferably, a plurality of individual sheets without tongues alternate with individual sheets with tongues such that the web portion has web elements and web recesses.

The web recesses, which can also be referred to as "gaps in the tangential web", are arranged on one or more permanent magnets on the air gap side, whereby the web elements, which generally consist of the sheet metal of an inserted laminated core, serve to provide the rotor assembly with the necessary mechanical properties during production In particular, the web region, in particular the web elements present therein, stabilizes the mass of a plastic used in an injection molding step The tangential web is basically a magnetic short between the pole shoes and should therefore have the greatest possible magnetic resistance in that the thickness, ie thickness, of the tangential web is reduced to the mechanically possible minimum dimension and thus a magnetic saturation is caused even at low magnetic fluxes cal resistance can be further increased by web recesses are present in the web part.

It has been found to be advantageous when using a laminated core of individual sheets, if to ensure the mechanical stability not every single sheet has a Stegausnehmung, ie the web is not opened at each individual sheet, so that sheets with gap or recess and sheets without gap alternate in a specific order. For example, every 10th or 5th plate can be designed with a web element and the rest with a web recess. The width of the Stegausnehmung can be optimized under several aspects. Thus, the stray flux is greater and thus the useful flow is smaller, the smaller the Stegausnehmung. Finally, the spectra of the magnetic fields in the air gap change, which can lead to increasing or decreasing torque-forming portions and thus amplified or reduced in torque higher order harmonics. There In particular, the last aspect of non-linear saturation conditions depends on the determination of an optimal width of the ridge recess usually no analytical consideration is made, but carried out a numerical FEM analysis with variation of the essential geometry parameters. For the present invention, a width of the web recess b _Ga in the range from 3.8 to 4.5 mm, preferably in the range from 4 to 4.3 mm, in particular a value of 4.2 mm, was found to be particularly advantageous.

For the production of individual sheets, a punching tool is generally used, it being possible to produce individual sheets with a web element and with a web recess in the punching tool.

The number of sheets with a web element essentially determines the mechanical properties of the rotor package, in particular in the production before encapsulation with a plastic. It is generally ensured that requirements are met in order to enable production of both the rotor with radially arranged permanent magnets and the rotor with surface-mounted permanent magnet described below as a component of the kit.

When using individual sheets in a laminated core, individual sheets can be formed with a continuous web, i. with a web element, identical to single sheets with a spring nose in the pocket for the permanent magnet. For example, the proportion of these individual sheets is at least 10%, but not more than 15% of the total laminated core. A decoupling of the number of single sheets with a continuous web, i. with web elements, and the individual sheets with a spring nose is possible if the stiffness of the rotor core and the spring force on the permanent magnets must be influenced independently.

The one or more tongues may each have a trapezoidal contour, wherein the tongue base portion is formed by the longer base of the trapezoidal tongues and the tongue tip portion is formed by the shorter base of the trapezoidal tongue. When using a trapezoidal shape, the spring stiffness can be formed progressive or degressive. When the tongue base portion is formed by the longer base of the trapezoidal tongue and the tongue tip portion is formed by the shorter base of the trapezoidal tongue, the spring stiffness decreases in the direction of the tongue portion, so that the tongue tip portion can be bent more easily. Conversely, the spring stiffness increases in the direction of the tongue base portion, so that with increasing bending of the tongues, the spring tension force, which biases the permanent magnets inside the pockets in the radially outward direction, increases.

The one or more tongues may each have a rectangular contour in one embodiment, wherein the spring stiffness over the entire length of the tongues is constant.

The stack of individual sheets can be formed from a first number of individual sheets, which have the tongues and are formed from a second number of individual sheets which are tongue-less, wherein the first number of individual sheets and the second number of individual sheets to form the stack of Laminated cores are arranged one above the other in a predetermined, alternating grouping. By the first number of individual sheets and the second number of individual sheets to form the stack of Blechpaktes are arranged one above the other in a predetermined, alternating grouping, the individual tongues are already spaced apart from each other by the appropriate stacking, so that correspondingly large distances are present between each two immediately adjacent tongues to allow sufficient bending of the tongues as soon as the individual permanent magnets are inserted into the pockets and the tongues are accordingly pushed aside by the permanent magnets.

The second number of individual sheets is in particular eight times to twelve times larger than the first number of individual sheets. Such a ratio is particularly useful for providing, on the one hand, a corresponding sufficiently large number of tabs per pocket which can apply the required spring force over the entire axial length of the permanent magnets and, on the other hand, ensure that the tabs have sufficient space to resiliently engage as desired to be able to bend. In this case, the permanent magnet rotor on each pocket have a radially outwardmost possible stop, against which the respective inserted in his pocket permanent magnet is pressed by the spring device. All stops are preferably on the same diameter or radius, so that all permanent magnets are positioned by the spring device on the same outer diameter or radius. It is thus achieved that all permanent magnets, ie all poles of the permanent magnet rotor, produce the same magnetic effect in the annular air gap of the drive motor. If the stops are radially as far outside as possible, then the permanent magnets are positioned as close as possible to the annular gap of the drive motor due to the spring bias of the spring device, in particular the tongues.

Each pocket of the laminated core may have motor shaft remote an abutment device, which are formed by abutment edges of the individual sheets of the laminated core, which are formed by motor shaft remote edge portions of window sections of the individual sheets of the laminated core, which form the pockets in the stacked state of the laminated core.

The motor shaft remote edge portions of the window openings replace in this embodiment, the inwardly projecting lugs of the embodiment described above. The additional statements described in relation to the inwardly projecting lugs also apply to the edge portions of the window cutouts of this embodiment remote from the motor shaft.

The laminated core of the permanent magnet rotor can be formed from a stack of several individual sheets, which has a number of poles of the permanent magnet rotor corresponding number of window cut-outs, which form the pockets in the stacked state of the laminated core, wherein the window cutouts have a closed contour. If the window cutouts have a closed contour, then a closed laminated core is formed, in which the radially outer boundary walls of the permanent magnets are enclosed by the laminated core. As a result, a web element is realized in the sense of the invention. The laminated core of the permanent magnet rotor can be formed from a stack of a plurality of individual sheets, which has a number of poles of the permanent magnet rotor corresponding number of window openings, which form the pockets in the stacked state of the laminated core, the window sections on the motor shaft remote edge portion form an open-edge contour to to realize a gap in the tangential bridge.

Namely, if the window openings have an open-edged contour, then a Stegausnehmung forming open laminated core is obtained in which the radially outer boundary walls of the permanent magnets are not enclosed by the laminated core, but are exposed in the direction of the annular gap. In this embodiment, the permanent magnets may optionally be positioned even closer to the annular gap, i. be arranged on an even larger diameter or radius. Optionally, despite such an open laminated core, the permanent magnets may still be encapsulated with plastic, as described above.

The permanent magnets inserted in the pockets of the laminated core and prestressed by the spring device, in particular by the elastic tongues, can accordingly be encapsulated with a plastic in all embodiments.

The invention also relates to a household appliance, in particular dishwasher, washing machine, dryer or extractor hood, comprising an electric drive motor described herein. Finally, the subject of the invention is also a construction kit for an electric drive motor for household appliances, in particular a brushless DC motor (BLDC), with at least two types of permanent magnet rotors and / or stators, so that the electric drive motors have a defined power and / or rotational speed torque. Cover area, wherein for the kit a stator type and usable with this type of stator, interchangeable rotor types are provided, and wherein the interchangeable rotor types permanent magnet rotors with external permanent magnets and permanent magnet rotors in which in the radial direction permanent magnets in Circumferential direction of the permanent magnet rotor are arranged distributed with alternating polarity and magnetized in the tangential direction, are.

In this case, a BLDC motor is essentially in different sizes, which differ in particular in their axial lengths and in the intended power range. In this case, to increase the efficiency or the utilization of the permanent magnets in addition to a rotor type with external permanent magnets in particular also a rotor type with extending in the radial direction, arranged in pockets permanent magnets used. The latter rotors are also referred to as Spoke rotors.

The basis of the modular system is generally the magnetic design of the BLDC motor. This includes the design of electromagnetic active parts such as sheet metal (package), permanent magnet, winding. The axial length of these parts is a variant-dependent parameter.

Preference is given to such a kit in which length-dependent engine components extend over a staple length of 10 to 40 mm.

In particular, it is further divided into the magnetic design of the stator and the magnetic design of the rotor.

As far as the stator in the construction kit for an electric drive motor is concerned, the design of the stator lamination section remains unchanged in the region of the air gap between stator and rotor and the slots of the stator. However, the outer contour can be adapted to the installation situation, wherein a minimum yoke width is not exceeded, so that the electromagnetic properties are not affected by the change in the outer contour. In an insulating system to be used generally always the same end plates are used regardless of the axial length in general. The actual slot insulation can be achieved comparatively flexible by in particular tailored Isolierpaper. The configuration of the windings is basically freely selectable within given by the axial length and the wire diameter limits. In general, there are fixed winding configurations, which are characterized by the material of the winding, the diameter of the selected winding wire and the number of turns are determined. The contacting is generally uniform for all variants, for example by insulation displacement technology or a plug.

The axial length of the stator core is linked to the axial length of the rotor core. The number of variants of the rotor (also referred to herein as the "rotor package") and the stator (also referred to herein as the "stator pack") are therefore generally the same.

In the modular system there is usually a fixed number of independent variants of windings. These are not primarily dependent on the other parameters such as axial length and rotor topology. However, an engine variant is usually defined by a fixed allocation between axial length, rotor topology, number of windings and winding material. As already mentioned, two different rotor topologies are generally advantageously used in the construction kit according to the invention. In this case, a Nutzschlitzbreite is selected for the common use of a stator in the rule, which is favorable in both cases with regard to the resulting air gap, the minimization of Nutrasten by torque fluctuations and the possibilities of production and winding. In this case, a ratio T _P / b _N s between slot pitch and groove slot width in the range of 4.5 to 5.5, in particular in the range of 5 to 5.2 has been found to be advantageous. This results, for example, in a slot slot width b _N s of 3.3 mm.

The rotor in the modular system is provided in particular in two different topologies. A topology includes a rotor with surface mounted magnets. In this case, a laminated rotor yoke is generally pressed onto a shaft. On the rotor yoke then the permanent magnets are mounted and fixed usually with a bandage. This topology is available in different axial lengths, wherein the length of the rotor yoke is determined by the number of individual sheets in the laminated core. The shafts and the permanent magnets are adapted in their axial length of the respective variant. Usually, the same number of sheets are used for the rotor core as for the stator, so that a stamping process commonly used for the production can be carried out with a very small amount of waste. The second topology is implemented with radially embedded permanent magnets in the so-called Spoke design. In this case, permanent magnets are arranged like spokes in the rotor core so that their magnetization is oriented tangentially. As a result, the magnetic flux is collected in the poles or pole shoes, so that higher magnetic flux densities are achieved in the air gap. An additional torque component is generated via the reluctance effect of the laminated core. This second topology can be operated in the same stator without further changes in the components as the first topology. In the kit then arises only with respect to the stator another variant, if possibly the winding is adjusted in terms of number of turns and diameter of the wire. However, if this is not required, only one other rotor will be used. As a rule, further changes to the hardware are not necessary. In general, however, a software for controlling the electric drive motor is operated with an adapted parameter set. An inventively used rotor in Spoke design described herein allows a further increase in power density. This circumstance may be used either to improve the drive efficiency or to reduce the amount of material in the electromagnetic active parts or to combine both. It is generally considered that the Spoke design can cause increased torque fluctuation and increased running noise. In particular, a desired combination between an increased power density and a noise optimization can then be set.

The modular system according to the invention allows a substantially unlimited interchangeability of components, in particular of rotors. In order to achieve such an unrestricted interchangeability, the design of the design takes place under generally narrow specifications, in particular with regard to the outer diameter of the rotor. Preferably, the magnetic design is optimized in order to achieve, in interaction with the stator geometry, an optimum between the magnetic flux in the air gap, ie the power density, the reduction of the torque fluctuation, ie the running noise, and the mechanical strength. For this purpose, in particular the contour of the air gap of the rotor can be varied and adapted. There the magnetic circuit is partially highly saturated, such an investigation will generally be done by numerical FEM simulation.

The aforementioned torque fluctuation basically consists of two components. The first component is the already mentioned grooved, resulting from the magnetic preferred positions between groove and tooth and pole. The second component is created by harmonics in the magnetic field of the air gap or in the torque-forming portions, which are caused by a field and armature field. To reduce these proportions is generally used to different methods, for example, to adapt the geometry of the air gap. As a rule, the stator is no longer changed, but only the rotor optimized. For the outer contour of the rotor, there are various possibilities, in particular a simple circular shape with a constant radius or a so-called "flower shape." In the "flower shape", the air gap in the area of the pole transitions is widened, so that the teeth are less engaged the Poles takes place. As a rule, a general decrease of the so-called permanent-excited air gap flux due to the enlargement of the effective air gap as well as the modulation of the mechanical air gap, which can lead to undesired noises, must be considered. The length of the air gap is generally determined by various factors. It is generally due to the manufacturing conditions to maintain a minimum gap, for example, 0.4 mm. With regard to an optimal utilization of the permanent magnets, ie the largest possible magnetic flux in the air gap, the gap should be as small as possible. The smaller the air gap, the more pronounced, however, is the cogging and thus a possible noise development. In general, an optimum is set between cogging and utilization of the magnetic flux. According to the invention, an optimum air gap length δ in the range of 0.5 to 0.7 mm, in particular 0.6 mm was found. The electrical drive motors of the modular system are generally controlled with a uniform software, which is adapted in each case with an individual parameter set. In general, a uniform electronics is used for motor control. In addition, all other parts that are needed for the mechanical structure of the electric drive motors, also designed uniformly. Thus, in general, the end shields made of die-cast aluminum and bearing seats and bearings, at least in the application in a washing machine do not differ. For other applications, eg in an extractor hood, the end shields for the connection can also be modified.

Incidentally, the above statements apply to the rotor preferably used in the electric drive motor with a specially designed web part.

The invention has numerous advantages. The electric drive motor according to the invention can be operated with greater efficiency, since the permanent magnets can be better utilized. This is possible without compromising the stability of the rotor, in particular also during the production process, for example in an injection molding step. The modular system according to the invention for an electric drive motor for household appliances has the advantage that it comprises in particular BLDC motors with several types of stators or rotors, wherein only a few variants of stators and rotors are used, which are substantially interchangeable with each other. For at least two types of BLDC motors for different domestic appliance series, the number of individual parts for the respective electric drive motors to be provided, in particular BLDC motors, can be minimized by rationalization effects being achievable by standardizing parts over larger quantities. The modular system according to the invention allows a flexible adaptation of the electric drive to a respective application without the complexity increasing excessively. The manufacturing costs and the efficiency of the electric drive motor are thus scalable and can be optimized against each other. New variants can be operated out of the kit. In addition, new variants in their operating behavior are well predictable or predictable. Variants can be produced with high flexibility, since only a partial change of production is required for a variant change. Finally, the storage is easier, because there are many equal parts. Further details of the invention will become apparent from the following description of essential to the invention components of an electric drive motor according to the invention. Reference is made to FIGS. 1 to 8. Regardless of the specific context in which they are mentioned, certain individual features of these exemplary embodiments, if appropriate also individually or in combinations other than those illustrated, may represent general features of the invention.

Show it:

Fig. 1 shows a permanent magnet rotor with pockets for permanent magnets, not shown here.

1, in which a pocket for a permanent magnet, not shown, as well as the transition region to an air gap is shown, which is arranged between the permanent magnet rotor and a stator, not shown here.

3 is a sectional perspective view of a permanent magnet rotor according to the invention with a laminated core and arranged in pockets of the laminated core permanent magnet.

4 is a sectional perspective view of the permanent magnet rotor of Figure 3 with permanent magnets inserted, which are encapsulated by a plastic. 5 shows a perspective view of the permanent magnet rotor of FIG. 3 and FIG. 4 with the laminated core forming the pockets into which the permanent magnets are inserted;

Fig. 6 is a perspective view of the laminated core of the permanent magnet rotor with an alternating grouping of a few

Individual sheets from the group of the first number of individual sheets with lugs, and many individual sheets from the group of the second number of nonseless individual sheets, with removed permanent magnet; 7 shows an enlarged detail of a single sheet of a laminated core, wherein the single sheet is here a closed single sheet, which also has a rectangular nose; Fig. 8 shows an enlarged detail of a single sheet of a laminated core, wherein the single sheet is here an open single sheet, which also has no rectangular nose.

FIGS. 1 to 8 show components of an exemplary electric drive motor of an exemplary washing machine or a construction kit containing this drive motor, comprising a stator with pole shoes and at least one electrically controllable stator winding, and a permanent magnet rotor 1 rotatably mounted in the field of the stator winding while leaving an annular gap a motor shaft and a seated on the motor shaft laminated core 2, in each of which one of the permanent magnets 6 is inserted.

In this embodiment, the electric drive motor has a fixed outer stator and a rotatably mounted inner rotor 1. The permanent magnet rotor 1 has a plurality of poles, in particular eight poles. Each permanent magnet of the permanent magnet rotor 1 is assigned a pocket 5 in the laminated core 2.

Fig. 1 shows a permanent magnet rotor 1 of an otherwise not shown in detail according to the invention electric drive motor with pockets 5 for permanent magnets, not shown here. In the radial direction, a web part 8 is arranged at the end of the pocket 5. The web portion 8 includes web elements 9, which consist of the same material as the laminated cores 2 and in particular the stability of the permanent magnet rotor 1 serve. There are web recesses 10 between the web elements 9. 1 1 means a segment of laminated core 2.

Fig. 2 shows an enlarged detail of the permanent magnet rotor of Fig. 1, in which a pocket 5 for a permanent magnet, not shown, and the Transition region to an air gap 7 is shown, which is arranged between the permanent magnet rotor and a stator, not shown here.

The pocket 5 is bounded by a web portion 8, which consists of web elements and web recesses which are not further recognizable here. The Stegausnehmung has a width b _gap 12th

Fig. 3 shows a sectional perspective view of an inventively provided permanent magnet rotor 1 with a laminated core 2 and arranged in pockets 5 of the laminated core 2 permanent magnet 6. In each of the pockets 6, a single permanent magnet 6 is inserted and fixed in particular against slipping. In the embodiment shown here, all the permanent magnets 6 of the permanent magnet rotor 1 are formed identically, wherein they each have a cuboidal shape here. In this case, the two opposite largest boundary surfaces of the permanent magnet 6 may be aligned in the circumferential direction, as shown in particular in Fig. 3, wherein peripheral boundary surfaces form the poles of the magnets. The permanent magnets 6 are arranged distributed uniformly over the circumference of the permanent magnet rotor 1.

Each pocket 5 may have a shape corresponding to the shape of the permanent magnets 6, wherein the pocket 5 is slightly larger, so that in each case a single permanent magnet 6 can be inserted into a pocket 5. The laminated core 2 of the permanent magnet rotor 1 is here formed by several, in particular punched sheet metal blanks, as shown in Figures 6 to 8, which are congruently stacked one above the other (Fig. 6) and connected to form a compact package. The laminated core 2 can be made by a stamped packaging so far. The congruent stacked individual sheets 3 may be connected, for example by welding, riveting, staples or a stamped or Klebepacketierung.

The permanent magnet rotor 1 shown here has a spring device 16 which is designed to fix the permanent magnets 6 inserted into the pockets 5 in each case in radial directions outwards, as indicated in FIG. 3 by arrows P, within the pockets 5. In the embodiment shown here, the permanent magnets 6 have a large, substantially rectangular front boundary surface 21 pointing in the circumferential direction, ie in the direction of rotation of the rotor, and an opposite, equally sized, substantially rectangular rear boundary surface 22 pointing in the circumferential direction, ie counter to the direction of rotation , An inner narrow boundary surface 23 faces a rotor shaft and an opposite outer narrow boundary surface 24 forms a magnetic pole of the rotor 1. All edges of the cuboid permanent magnet 6 may be provided with a chamfer or be rounded. The spring device 16 can in principle be formed from one part, but also from several parts. The spring device 16 biases each individual permanent magnet 6 within its respective pocket 5 in a radially outwardmost possible position. In this case, the permanent magnet rotor 1 can have on each pocket 5 a stop device 18 located radially as far as possible, against which the respective permanent magnet 7 lying in its pocket 5 is pressed by the spring device 16. All stop devices 18 are preferably at the same radius, so that all the permanent magnets 6 are positioned by the spring device 16 on the same outer radius. This can ensure that all permanent magnets 6, ie all poles of the permanent magnet rotor 1 produce the same magnetic effect in the annular gap of the electric drive motor of the invention.

As in the case of the present exemplary embodiment, the spring device 16 can be formed by a plurality of, for example, five elastic tongues or lugs 17 per pocket 5, which protrude into the pockets 5, wherein a tongue 17 can be rectangular, for example (cf. Fig. 7).

In a specific application, the spring device 16 or their tongues 17 serves for the temporary fixing of the permanent magnets 6 inserted into the pockets 5 during manufacture and / or assembly of the permanent magnet rotor 1 until the permanent magnets 6 inserted in the pockets 5 by encapsulation of the laminated core 2 are finally secured with a plastic 20 in their positions. 6 shows how a laminated core 2 of the permanent magnet rotor 1 is formed from a stack of several individual sheets 3, which has a number of window cutouts 19 corresponding to the number of poles of the permanent magnet rotor 1 which form the pockets 5 in the stacked state of the laminated core 2, in which the permanent magnets 6 are used. The spring device 16, in particular the tongues 17, are formed by inwardly projecting edge portions of the window cutouts 19 of the individual sheets 3 of the laminated core 2.

As shown in particular in FIG. 6, the stack of individual sheets 3 can be formed from a first number of individual sheets, which have the tongues 17, and from a second number of individual sheets 3, which are tongue-less. The second number of individual sheets 3 may for example be eight times to twelve times larger than the first number of individual sheets. 3

In the radial direction, a web part 8 is arranged at the end of the pockets formed by the window cutouts 19. The web portion 8 includes web elements 9, which consist of the same material as the laminated core 2 and in particular the stability of the permanent magnet rotor 1 serve. In Fig. 7, a closed single sheet 25 is shown with a stop device 18 which is fixed in the laminated core 2 and against which the respectively inserted in one of the pockets 5 permanent magnet 6 by the one or more tongues 17 of the relevant pocket 5 is pressed spring-biased. In Fig. 7 is also shown that in the radial direction at the end of the pocket 5, a web portion 8 is arranged. The web portion 8 includes web elements 9, which consist of the same material as the laminated cores 2 and in particular the stability of the permanent magnet rotor 1 serve. In Fig. 7 in particular a single sheet is shown in Fig. 8 is a single sheet, in particular an open single sheet 15, shown with a web portion 8, in which a ridge recess 10 is present. In this single sheet has been dispensed with a tongue. reference numeral

1 permanent magnet rotor

2 laminated core

3 individual sheets

4 poles

5 pockets

6 permanent magnets

7 air gap (between stator and rotor)

8 web part, web area

9 web elements

10 rib recesses

1 1 segment

12 width of the web recess b _gap

13 Length of the web recess

14 Thickness of a single sheet

15 open individual sheets

16 spring device

17 noses, tongues

18 stop device

19 window openings

20 plastic

21 front boundary surface (of a permanent magnet)

22 rear boundary surface (of a permanent magnet)

23 inner narrow boundary surface (of a permanent magnet)

24 outer narrow boundary surface (of a permanent magnet)

25 closed individual sheets

Claims

An electric drive motor comprising a stator with teeth and grooves, and a permanent magnet rotor (1) having a motor shaft and a laminated core (2) seated on the motor shaft, which has at least one of the number of poles (4) of the permanent magnet rotor (1) Pockets (5), in which in the radial direction in each case a permanent magnet (6) is arranged, the permanent magnets (6) in the circumferential direction of the permanent magnet rotor (1) arranged distributed with alternating polarity and magnetized in the tangential direction, so that one of the respective Permanent magnet (6) outgoing magnetic flux in the tangential direction of the permanent magnet rotor (1) extends, and the permanent magnets (6) extend in the axial direction of the permanent magnet rotor (1) beyond the laminated core (2), and wherein between adjacent pockets (5) respectively a segment (1 1) of the laminated core (2) is arranged, which is formed, the magnetic n concentrate the flow of the respective permanent magnets (6) in an air gap (7) between stator and permanent magnet rotor (1), wherein the laminated core (2) via a respective permanent magnet (6) on the side of the air gap (7) in the axial direction of the permanent magnet rotor (1) extending web portion (8) which connects two segments (1 1) of the laminated core (2) with each other, characterized in that the web portion (8) web elements (9) and web recesses (10).

Electric drive motor according to claim 1, characterized in that the web recesses (10) in the tangential direction each have a same width b _g ap (12).

Electric drive motor according to claim 2, characterized in that b _gap (12) by means of the formula I bgap = a _gap / 180 * TT ^* r (I) where r is an outer radius of the permanent magnet rotor (1) and cigap is calculated by the formula II a _gap / = 360 (2p ^* N / gcd) / 2 (II), where 2p is the number of poles (4) , N means the number of slots in the stator and gcd is the largest common divisor of the two.

Electric drive motor according to one of claims 1 to 3, characterized in that the laminated core (2) of the permanent magnet rotor (1) is formed from a stack of a plurality of individual sheets (3).

Electric drive motor according to claim 4, characterized in that the web recesses (10) have a length l _gap (13) in the axial direction of the permanent magnet rotor (1), which is an integer multiple of a thickness d (14) of a single sheet (3).

Electric drive motor according to one of claims 1 to 5, characterized in that the web recesses (10) are formed by a stack of open individual sheets (15) and the web elements (9) by closed individual sheets (25).

Electric drive motor according to claim 6, characterized in that the proportion of the closed individual sheets (25), based on the sum of open and closed individual sheets, in the range of 5 to 20%.

Electric drive motor according to one of claims 1 to 7, characterized in that a spring device (16) is formed in order to fix the permanent magnets (6) inserted into the pockets (5) in each case in radial directions outwardly biased within the pockets (5) wherein the spring device (16) is formed by in each case one or more elastic lugs (17) projecting into each one of the pockets (5) and each pocket (5) has a stopper device (18) remote from the motor shaft and attached to the laminated core (2). is set and against the respectively in one of the pockets (5) used Permanent magnet (6) by the one or more lugs (17) of the respective pocket (5) is pressed spring biased.

9. Electric drive motor according to claim 8, characterized in that the laminated core (2) is formed from a stack of individual sheets (3) and the spring device (16), in particular the one or more elastic lugs (17), by inwardly projecting edge portions of window cutouts (19) of the individual sheets (3) are formed.

10. Electric drive motor according to one of claims 1 to 9, characterized in that the laminated core (2) contains individual sheets (3) which are formed as closed individual sheets (16), in which an elastic nose (17) of a spring device (16). are formed by inwardly projecting edge portions of window cutouts (19) of the individual sheets (3). 1 1. Electric drive motor according to one of claims 1 to 10, characterized in that in the pockets (5) of the laminated core (2) used permanent magnets (6) are encapsulated by plastic (20).

12. Electric drive motor according to one of claims 1 to 1 1, characterized in that the outer contour of the permanent magnet rotor (1) is circular.

13. Household appliance, in particular dishwasher, washing machine, dryer or extractor hood, comprising an electric drive motor according to one of claims 1 to 12.

14. A kit for an electric drive motor for household appliances, in particular a brushless DC motor (BLDC), having at least two types of permanent magnet rotors and / or stators, so that the electric drive motors have a defined power and / or rotational speed torque

Cover area, characterized in that for the kit, a stator type and with this type of stator usable, interchangeable rotor types are provided, wherein the interchangeable rotor types Permanent magnet rotors with external permanent magnets as well

Permanent magnet rotors (1), in which in the radial direction permanent magnets (6) distributed in the circumferential direction of the permanent magnet rotor (1) arranged with alternating polarity and are magnetized in the tangential direction, are. 15. Modular system according to claim 14, characterized in that length-dependent engine components extend over a staple length of 10 to 40 mm.