Rotor, electric motor, pump device, household appliance and production method

Abstract

The invention relates to a rotor, an electric motor, a pump device, a household appliance and a production method. A rotor 10 for an electric motor 100 is disclosed. The rotor comprises a ring portion 11 and a hub portion 12, wherein the ring portion 11 comprises permanent magnetic material and is configured to rotate at least partially around at least a portion of a stator 20 of the electric motor 100. The hub portion 12 is configured as a fan comprising two or more vane elements 12a, 12b, 12c, 12d, each connected to the ring portion 11, which vane elements enclose two or more axial air passages P. Further disclosed is an electric motor 100 comprising such a rotor 10, a pump device 1000 and a household appliance each comprising such an electric motor 100 and a method of producing a rotor 10.

Description

Technical Field

[0001] The present invention relates to rotors for electric motors, electric motors including such rotors, pump devices and household appliances including such electric motors, and methods for producing said rotors. Background Technology

[0002] Electric household appliances typically include an electric motor, which can be specifically configured to drive the impeller of a rotary tool or pump. Different types of rotors are known to be included in corresponding electric motors. Summary of the Invention

[0003] The object of this invention is to provide an improved permanent magnet rotor for a household appliance, and a method for producing such a rotor. Another object of this invention is to provide an improved electric motor, pump device, and household appliance.

[0004] The objectives are achieved by rotors, electric motors, pumps, household appliances, and methods, respectively. Preferred embodiments are disclosed in the specification and drawings.

[0005] The rotor according to the invention is configured to form part of an electric motor. It includes a ring portion and a hub portion. The ring portion contains a permanent magnet material; specifically, the rotor is a permanent magnet rotor. The ring portion is configured to rotate at least partially (i.e., at least a portion thereof) about at least a portion of the stator of the electric motor. That is, when the rotor is mounted in the electric motor, at least a portion of the rotor is located radially outside at least a portion of the stator. It should be understood that in this document, the term "radial," as well as the terms "axial" and "circumferential," refer to the specified axis of rotation of the rotor, and this also applies to their respective language derivatives.

[0006] The hub portion of the rotor according to the invention is configured as a fan: it includes two or more (preferably at least three or at least four) blade elements, each blade element being connected (preferably at its respective radially outer end) to a ring portion, wherein the blade elements surround two or more air passages extending in the axial direction.

[0007] Because axial air passages are provided between the blade elements in the hub portion, the present invention integrates and promotes airflow axially through the rotor and the stator portion surrounding the rotor. This, in turn, promotes improved cooling of the electric motor components, particularly the stator windings, at least one stator stack, and / or one or more bearing elements that rotatably support the rotor, thereby increasing the durability of the electric motor. For example, it can at least slow down the deterioration of the electric motor components such as the stator windings, stator slot insulation, bearing system, and / or its lubrication.

[0008] In particular, compared to conventional electric motors, the utilization rate of the active components of the electric motor can be increased without causing a rise in the operating temperature of the electric motor. Specifically, the electric motor can be manufactured with smaller external dimensions and / or using fewer active materials (such as magnetic materials, copper, and / or iron-containing materials), while maintaining performance.

[0009] In addition, compared with conventional rotors having a flat, continuous hub section, providing air passages in the hub section promotes material savings and thus promotes a reduction in rotor mass.

[0010] According to a preferred embodiment, the device includes a rotor or is configured to be included in a household appliance, such as a household appliance that includes a pump.

[0011] The blade elements may extend radially, either directly or in a curved shape. The rotor may further include a shaft. This shaft may be rotatably fixed to the hub (i.e., connected to the hub for mutual rotation).

[0012] According to an advantageous embodiment, the rotor includes an integral portion comprising a ring portion and a hub portion. That is, both the ring portion and the hub portion of the rotor can be integrated into a common integral portion. This allows for increased stability and durability of the rotor. In particular, this integral portion can be produced by injection molding and / or by additive manufacturing.

[0013] At least a portion of the rotor, preferably its ring portion and / or hub portion, may be at least partially made of plastic material. Thus, the rotor can be particularly lightweight. In particular, the rotor is advantageously at least partially made of a plastic magnetic material. Preferably, both the hub portion and the ring portion are at least partially made of the same (ordinary) plastic material.

[0014] In embodiments where the rotor comprises an integral part, as described above, the integral part includes a ring portion and a hub portion, and in particular, this integral part may be made of a plastic (plastic magnet) material.

[0015] According to a preferred embodiment, at least one of the blade elements has at least one section with a thinning edge, in which the blade element thins towards the edge defining the at least one blade in the circumferential direction (measured in the axial direction). This thinning edge may, in particular, be chamfered and / or rounded. Preferably, the at least one blade element has two such sections with thinning edges, which are opposite each other in the circumferential direction. In particular, at least one of the blades may have a streamlined shape in the circumferential direction.

[0016] When the rotor rotates, these embodiments achieve an improved airflow generated by the hub portion configured as a fan.

[0017] The hub portion can advantageously be non-magnetic.

[0018] The ring portion can be irregularly magnetized. Specifically, the ring portion may include a (preferably annular) first sub-section and a (preferably annular) second sub-section, wherein the ring portion may have a weaker magnetic field in the second sub-section than in the first sub-section. In particular, the second sub-section may be non-magnetic, and / or the ring portion (or even the rotor (as a hole)) may be anisotropic only in the first sub-section of the ring portion.

[0019] This reduces the consumption of permanent magnet material during rotor production. In particular, it avoids including permanent magnet material in the ineffective sub-sections of the rotor.

[0020] The second sub-section of the ring portion can separate the first sub-section from the hub portion, particularly in the axial direction. That is, the second sub-section can be arranged between the first sub-section and the hub portion (particularly in the axial direction). For example, the axial dimension of the first sub-section can be smaller than the axial dimension of the (total) ring portion. When the electric motor operates, these embodiments achieve a reduction (or even elimination) of the axial force between the rotor and the stator, particularly its stator stack. In particular, frictional losses caused by this axial force can be reduced or even suppressed.

[0021] According to an advantageous embodiment, the radially outer surface of the ring portion narrows towards the hub portion. This saves material required for rotor production, and the rotor can have a particularly low mass. Specifically, in the embodiment described above, which includes first and second sub-sections with different magnetic fields, the first sub-section can have a larger diameter (measured radially, respectively) than the second sub-section.

[0022] Regarding the axial direction, the ring portion (particularly, in the corresponding embodiment, its first sub-portion) can preferably have a deflected magnetization direction. The corresponding angle between the magnetization direction and the parallel line to the designated axis of rotation of the rotor can preferably be greater than 5°, greater than 10°, or greater than 15°, and / or less than 40°, less than 35°, or less than 30°. This allows for a reduction in motor cogging torque.

[0023] A method according to the invention is used to produce a rotor according to embodiments of the invention. The method includes manufacturing at least the ring portion and / or hub portion of the rotor by injection molding and / or by additive manufacturing. This ensures rapid yet reliable production.

[0024] An electric motor according to the present invention includes a stator and a rotor according to an embodiment of the present invention. At least a portion of the stator is arranged to be surrounded by at least a portion of the annular portion of the rotor.

[0025] A pump device according to the invention includes an impeller and an electric motor according to an embodiment of the invention. The impeller is configured to be driven by the electric motor. The pump device can be a wet or dry pump device. In particular, it can be configured to pump liquids (such as water) or gases (such as air).

[0026] A household appliance according to the present invention includes an electric motor according to an embodiment of the present invention. In particular, the household appliance may include an electric pump according to an embodiment of the present invention. The household appliance may be, for example, a washing machine, dishwasher, dryer, kitchen range hood, or ventilation fan. Attached Figure Description

[0027] Preferred embodiments of the invention are explained below with reference to the accompanying drawings. It should be understood that various elements and components are illustrated only as examples and may be combined in a manner different from those illustrated. Reference numerals for related elements are used syntactically and are not redefined for each drawing.

[0028] The accompanying drawings schematically illustrate:

[0029] Figure 1 A rotor according to an exemplary embodiment of the present invention is shown in a perspective view;

[0030] Figures 2a to 2d Different views of an exemplary rotor according to the present invention are shown;

[0031] Figure 3 A cross-section of an electric motor according to an embodiment of the present invention and airflow are shown;

[0032] Figure 4 An exploded view of the components of an electric motor according to an embodiment of the present invention is shown;

[0033] Figure 5 A cross-section of the pump assembly according to the invention and the cooling airflow are shown. Detailed Implementation

[0034] Figure 1 An exemplary embodiment of the rotor 10 according to the present invention is shown.

[0035] The rotor 10 includes a ring portion 11, a hub portion 12, and a shaft 13. The ring portion 11 is configured to at least partially surround at least a portion of the stator of the electric motor (such as surrounding a... Figure 3 The stator 20 shown in the figure rotates (i.e., rotates together with at least a portion thereof). In particular, the rotor 10 may be included in an electric motor included in a (dry or wet) pump device.

[0036] In the illustrated embodiment, the ring portion 11 and the hub portion 12 are integrated into a common integral portion. This makes the rotor 10 particularly robust.

[0037] like Figure 1 As seen, the hub portion 12 is configured as a fan: in the illustrated exemplary case, it includes (exactly) four blade elements 12a, 12b, 12c, 12d, each blade element extending in a radial direction (relative to a designated axis of rotation X of the rotor 10) and connected to the ring portion 11 at its respective radially outer end. An axial air passage P is provided between every two adjacent blade elements in the circumferential direction.

[0038] Therefore, in the operation of the electric motor including the rotor 10, an airflow is achieved through the internal region surrounded by the ring portion 11 and then through the air passage P, which is used to cool the components of the electric motor. Additionally, the air passage reduces the mass of the rotor.

[0039] Preferably, at least the ring portion 11 and / or the hub portion 12 of the rotor 10 are made of plastic material, particularly plastic magnet material. This manufacturing can be achieved by injection molding and / or additive manufacturing.

[0040] In the illustrated embodiment, the ring portion 11 includes a first sub-portion 11f and a second sub-portion 11s. In the axial direction (i.e., parallel to the designated axis of rotation X), the second sub-portion 11s is arranged between the hub portion 12 and the first sub-portion 11f, thus separating them in the axial direction. The second sub-portion 11s connects the first sub-portion 11f (of the ring portion) and the hub portion 12. In the illustrated embodiment, both the first and second sub-portions have an annular shape.

[0041] Configured to at least partially surround the stator ( Figure 1 The rotating at least first sub-part (not shown) contains permanent magnet material ( Figure 1 (Not visible in the middle). The magnetic field is weaker in the second sub-part 11s than in the first sub-part 11f. Therefore, magnet material can be saved.

[0042] For example, the second sub-part 11s can be non-magnetic (non-magnetic), such that only the first sub-part 11f of the ring portion has a magnetic field. In particular, the first sub-part 11f can be anisotropic, and the second sub-part 11s can be isotropic.

[0043] Thus, in the operation of the electric motor including the rotor 10, the axial force between the rotor 10 and the stator stack can be reduced or even prevented, which minimizes frictional losses.

[0044] like Figure 2aAs illustrated in the diagram (showing a cross-section of rotor 10 taken along a specified axis of rotation X), the second sub-part 11s has a diameter d (measured radially relative to the specified axis of rotation X), which is smaller than the diameter D of the first sub-part 11f (also measured radially relative to axis X). In particular, the radially outer surface of the ring portion 11 narrows toward the hub portion 12.

[0045] Figure 2b and Figure 2c All show the corresponding cross sections orthogonal to the axis of rotation X, such as Figure 2a The figures are indicated by markings AA and BB, respectively, with the viewing direction in both figures pointing towards the hub portion 12 of the rotor 10. Figure 2d In the figure, a cross section parallel to the axis of rotation X is shown, as shown in the figure. Figure 2c (in Chinese) is indicated by the mark CC.

[0046] like Figures 2b to 2d As seen, each pair of adjacent blade elements 12a, 12b, 12c, 12d in the circumferential direction is separated by a corresponding air passage P. At their edges, blade elements 12a, 12b, 12c, 12d all thin towards the air passage P.

[0047] To improve clarity of the accompanying drawings, reference is made only to the thinning edges 12a-i and 12a-ii of blade element 12a and the thinning edges 12b-i and 12b-ii of blade element 12b; it should be understood that blade elements 12c and 12d are similarly shaped.

[0048] Among them, such as Figures 2b to 2d As can be seen, at their circumferentially opposite edges, blade elements 12a and 12b both thin out in opposite directions. That is, the thinning edges 12a-i and 12a-ii at the opposite edges of blade element 12a face opposite directions (parallel to the axis of rotation X), making the thinning edges identifiable from different sides. This also applies to the thinning edges at the opposite edges of other blade elements.

[0049] In fact, in the direction of observation from the space surrounded by the ring portion 11 toward the hub portion 12 Figure 2b In the middle, only the thinning edges 12a-i and 12b-i are visible. In contrast, in the opposite viewing direction... Figure 2c In the image, the thinning edges 12a-ii and 12b-ii can be seen.

[0050] like Figure 2d As is particularly evident, blade element 12b has a cross section with second-order rotational symmetry.

[0051] like Figure 2dThe illustration further shows that the thinned edges 12b-i and 12b-ii of the blade 12b (and other blade elements) illustrated in the exemplary embodiment are rounded. According to an alternative embodiment, the edges of the blade elements may include chamfered sections; in particular, the thinned edges may be flat.

[0052] According to a preferred embodiment, the ring portion, particularly its first sub-segment 11f, has a magnetization direction skewed relative to a specified rotation axis X. Figure 2d In this context, the skew angle α between the magnetization direction and the line parallel to the rotation axis X is indicated. Preferably, this angle α is greater than 5°, greater than 10°, or greater than 15°, and / or less than 40°, less than 35°, or less than 30°. This allows for a reduction in motor cogging torque.

[0053] exist Figure 3 In the diagram, rotor 10 is shown as included in an electric motor 100 according to an exemplary embodiment of the invention, the electric motor 100 being illustrated in a cross section along a dedicated axis of rotation X of rotor 10.

[0054] In addition to the rotor 10, the electric motor 100 also includes a stator 20, which includes stator windings; Figure 3 In the cross-section, the stator windings 21a and 21b are visible. The stator is held by a first housing component 30, which is connected to a second housing component 40, which surrounds the annular portion 11 and hub portion 12 of the rotor 10, as well as the stator windings. The shaft 13 is rotatably mounted in the combined first and second housing components 30 and 40 by means of bearing elements 51 and 52.

[0055] An air inlet I is provided in the first housing member 30, and an air outlet O is provided in the second housing member 40. Since the hub portion 12 of the rotor 10 according to the invention is configured as a fan, it promotes cooling airflow, as in… Figure 3 As indicated by the arrow: Therefore, the air entering the electric motor 100 through the air inlet I can cool the internal components of the electric motor (such as the stator windings and / or bearing elements 51, 52). The air can be heated by these components and exits the motor through the air outlet O.

[0056] exist Figure 4 The exploded view shows how the rotor 10 is installed. Figure 3 The electric motor 100 shown is in the second housing component 40. Thus, in particular, a perspective view of the second housing component 40 is provided.

[0057] Figure 5 A pump 1000 according to an embodiment of the present invention is illustrated. In particular, such a pump can be included in household appliances such as washing machines, tumble dryers, or dishwashers.

[0058] Pump 100 includes an electric motor 100 according to the invention. The shaft 13 of the rotor 10 of the electric motor 100 is connected to the impeller 200 of the pump 100 and is thus configured to drive the impeller 200 within the pump housing 300.

[0059] Figure 5 The arrows in the diagram illustrate the cooling airflow through the electric motor 100 facilitated by the present invention.

[0060] A rotor 10 for an electric motor 100 is disclosed. The rotor includes a ring portion 11 and a hub portion 12, wherein the ring portion 11 contains a permanent magnet material and is configured to rotate at least partially about at least a portion of the stator 20 of the electric motor 100. The hub portion 12 is configured as a fan including two or more blade elements 12a, 12b, 12c, 12d, each blade element being connected to the ring portion 11, the blade elements surrounding two or more axial air passages P.

[0061] Further disclosed is an electric motor 100 including such a rotor 10, a pump device 1000 including such an electric motor 100, and a household appliance, as well as a method for producing the rotor 10.

[0062] Figure label:

[0063] 10 rotors

[0064] 11 rings

[0065] 11f First Sub-part

[0066] 11s Second Sub-part

[0067] 12 hub section

[0068] Blade elements 12a, 12b, 12c, and 12d

[0069] Thinning edges of 12a-i, 12a-ii, 12b-i, and 12b-ii

[0070] 13 axes

[0071] 20 stators

[0072] 21a and 21b stator windings

[0073] 30 First housing component

[0074] 40 Second housing component

[0075] 51, 52 bearing components

[0076] 100 electric motors

[0077] 200 impeller

[0078] 300 Pump Housing

[0079] 1000 pumps

[0080] α Deflection angle

[0081] d Diameter of the second sub-part 11s

[0082] D Diameter of the first sub-part 11f

[0083] I. Air Inlet

[0084] O air outlet

[0085] P air passage

[0086] X specifies the axis of rotation.

Claims

1. A rotor (10) for an electric motor (100), the rotor comprising a ring portion (11) and a hub portion (12). The ring portion (11) contains a permanent magnet material and is configured to rotate at least partially around at least a portion of the stator (20) of the electric motor (100). Furthermore, the hub portion (12) is configured as a fan comprising two or more blade elements (12a, 12b, 12c, 12d), each blade element being connected to the ring portion (11), the blade elements surrounding two or more axial air passages (P). The ring portion (11) comprises a first sub-portion (11f) and a second sub-portion (11s), wherein in the second sub-portion (11s), the ring portion (11) has a weaker magnetic field than in the first sub-portion (11f), and The rotor (10) wherein at least the ring portion (11) and / or the hub portion (12) is made of a plastic magnetic material.

2. The rotor according to claim 1, wherein at least one of the blade elements (12b) has at least one section with a thinning edge (12a-i, 12b-i, 12b-ii) in which the at least one blade element thins toward the edge defining the at least one blade in the circumferential direction.

3. The rotor according to claim 1, wherein in the axial direction, the second sub-part (11s) separates the first sub-part (11f) from the hub part (12).

4. The rotor according to any one of the preceding claims, wherein the radial outer surface of the ring portion (11) narrows toward the hub portion (12).

5. An electric motor (100) comprising a rotor (10) and a stator (20) according to any one of the preceding claims.

6. A pump device (1000) comprising an impeller (200) and an electric motor (100) according to claim 5.

7. A household appliance comprising an electric motor (100) according to claim 5 and / or a pump device (1000) according to claim 6.

8. A method of producing a rotor (10) according to any one of claims 1 to 4, the method comprising manufacturing at least a ring portion (11) and / or a hub portion (12) by injection molding and / or by additive manufacturing.

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