Stator for rotating electric machines

Abstract

A stator for a rotating electric motor is disclosed, the stator comprising a stack of stator laminates (20) forming a stator core (48; 60; 74; 80; 82). The laminate (20) comprises a plurality of heat dissipation fins (28) arranged in at least one group comprising at least two fins. The heat dissipation fins in the fin groups are connected by peripheral connecting members (30). The laminates are arranged in the form of laminate groups comprising at least one laminate. A fin group (28) in one laminate group is circumferentially located between two adjacent fin groups in an adjacent laminate group. A heat dissipation fin (28) in one laminate group is inserted between two heat dissipation fins in a group of heat dissipation fins in another non-adjacent laminate group. This allows for excellent thermal performance while providing excellent mechanical strength and reducing manufacturing costs.

Description

Technical Field

[0001] The present invention relates to stators for rotating electric machines, and more particularly, to stators having heat dissipation fins for cooling the stator. Background Technology

[0002] Rotating electrical machines, such as motors and generators, typically consist of a rotor and a stator, with the rotor mounted on a shaft and arranged to rotate within the stator. The rotor generates a rotating magnetic field across the air gap between the rotor and the stator. The stator includes a stator core that holds stator windings that combine with the rotating magnetic field. The stator itself can be held within a stator frame, with an air gap between them.

[0003] When an electric motor is running, the current flowing through the stator and / or rotor windings, along with other factors such as friction and windage losses, causes the motor to heat up. Therefore, many motors, especially those with larger designs, require some form of cooling. This can be achieved by providing a fan that pushes airflow through the motor. Typically, the airflow flows through the motor in a generally axial direction. The main path of the airflow passes through the rotor / stator air gap and through the air gap between the stator core and the stator frame.

[0004] A stator core with heat dissipation fins is known. The heat dissipation fins typically extend radially outward from the stator core into the air gap between the stator core and the stator frame to increase heat transfer from the stator core to the cooling air.

[0005] The stator of a rotating electric motor is typically formed by stacking laminates. Laminates are usually stamped from a roll or sheet of electrical steel. During the manufacturing of laminates, a certain amount of raw material may be left over and discarded as waste. However, it is desirable to reduce the amount of waste in order to lower manufacturing costs.

[0006] The subject matter of WO 2005 / 022718 A1, which is incorporated herein by reference, discloses a laminated stator with heat dissipation fins, in which staggered rows of heat dissipation fins are formed on the outer side of the stator. The staggered heat dissipation fins can improve heat transfer from the stator to the cooling air passing through the stator.

[0007] The subject matter of which is incorporated herein by reference, US 210 / 02077465, discloses a stator for a rotating electric motor, the stator comprising a stack of laminates, the sub-assemblies of which have extensions. Each extension includes a plurality of fins connected at its outer ends via peripheral connections.

[0008] While known heat sink fin arrangements can offer some improvements in stator cooling, various problems have been identified. Specifically, known arrangements may be complex to manufacture, inefficient in terms of material usage, and / or lack mechanical stability. Previous attempts to address these issues have often sacrificed cooling efficiency. Therefore, there is a need for heat sink fin arrangements that allow for excellent thermal performance while providing excellent mechanical strength and cost savings in manufacturing. Summary of the Invention

[0009] According to one aspect of the invention, a stator for a rotating electric motor is provided, the stator comprising a stack of stator laminates forming a stator core, wherein:

[0010] The laminate includes a plurality of heat dissipation fins, which are arranged in the form of at least one fin group comprising at least two fins.

[0011] The heat dissipation fins in the fin assembly are connected by peripheral connecting components;

[0012] The laminates are arranged in the form of a laminate group including at least one laminate;

[0013] The fin groups in a laminate assembly are circumferentially located between two adjacent fin groups in an adjacent laminate assembly; and

[0014] A heat sink fin in one laminate assembly is inserted between two heat sink fins in another (non-adjacent) laminate assembly.

[0015] The advantages offered by this invention are that by providing a set of heat dissipation fins connected by peripheral connecting members to the laminates, and inserting heat dissipation fins in one laminate between two heat dissipation fins in a set of heat dissipation fins in another laminate, a staggered heat dissipation fin arrangement can be achieved. This arrangement provides excellent heat transfer from the stator to the cooling fluid, while also providing excellent mechanical stability. Furthermore, this invention can provide improvements in material usage and / or manufacturing convenience.

[0016] "Intercalation" preferably means that, when viewed axially, the heat dissipation fins in one laminate group are located between two heat dissipation fins in another laminate group. Therefore, the heat dissipation fins in one laminate group are preferably circumferentially intercalated between two heat dissipation fins in a set of heat dissipation fins in another laminate group (e.g., the laminate group on the other side of the adjacent laminate group).

[0017] Preferably, the heat dissipation fins extend in a generally radial direction, and the peripheral heat dissipation components extend in a generally circumferential direction (although some deviations relative to the radial and circumferential directions are certainly possible). For example, the laminate may include an annular body with an outer edge, and the heat dissipation fins may extend radially outward from the outer edge. This allows the heat dissipation fins to extend into the air gap between the stator and stator frame in the assembled motor. Preferably, stator slots for accommodating stator windings are provided radially inward of the annular body.

[0018] Preferably, a gap for cooling fluid is provided between adjacent heat dissipation fins in the fin assembly. The gap is preferably located radially below the peripheral connecting member. Therefore, the peripheral connecting member can bridge the gap between two adjacent heat dissipation fins in the fin assembly. This facilitates the flow of cooling fluid through the assembled motor.

[0019] Preferably, the peripheral connecting member connects the radially outward ends of the fins in a set of fins. This helps ensure that the heat dissipation fins have sufficient mechanical strength while allowing for gaps between adjacent heat dissipation fins in a set of fins for cooling fluid.

[0020] In some cases, a laminate assembly may comprise a single laminate. In this case, consecutive laminates may be rotated relative to each other (rotated about their axis). However, since the laminates may be relatively thin, this results in heat dissipation fins that can be easily deformed. Therefore, a laminate assembly may comprise multiple laminates adjacent to each other in the axial direction (e.g., 2, 3, 4, 5, 6, 7, 8, or more laminates). The laminates in the assembly may be rotatably aligned. However, the laminate assembly may be rotated relative to each other. Thus, in the assembled stator, the thickness of the heat dissipation fins in the axial direction may be equal to the total thickness of the laminates in the assembly. This helps ensure that the heat dissipation fins have the necessary mechanical strength. All assemblies may have the same number of laminates, or different assemblies may have different numbers of laminates as appropriate.

[0021] Preferably, the heat dissipation fins in one laminate assembly are circumferentially inserted between two heat dissipation fins in a set of heat dissipation fins in a laminate assembly located on the other side of an adjacent laminate assembly (i.e., adjacent to the adjacent laminate assembly). This helps to ensure an air gap in the axial direction between the heat dissipation fins, which can aid in cooling.

[0022] Preferably, the heat dissipation fins of one laminate group are staggered relative to the heat dissipation fins of another laminate group. Therefore, cooling fluid passing axially between two fins in one laminate group can encounter heat dissipation fins in another laminate group. This increases the amount of cooling fluid flowing around the heat dissipation fins and / or helps introduce turbulence, both of which contribute to heat transfer from the stator to the cooling fluid.

[0023] Preferably, the stator comprises multiple laminates having at least one set of heat dissipation fins. Therefore, some or all of the laminates may include at least one set of heat dissipation fins. This helps ensure that sufficient heat dissipation fins are provided for effective cooling.

[0024] Preferably, at least some of the laminates include multiple sets of heat dissipation fins (e.g., two, three, four, five, six, or more sets of heat dissipation fins). Therefore, the stator may include multiple laminates, each having multiple sets of heat dissipation fins, each set comprising multiple heat dissipation fins connected by peripheral connecting members. This helps ensure a sufficient number of heat dissipation fins are provided while also helping to ensure structural integrity.

[0025] In some embodiments, at least one set of fins may have a different number of fins than another set of fins in the same laminate. For example, in the same laminate, the number of fins in one set of fins may be 1 higher than the number of fins in another set of fins. This can facilitate, for example, achieving a staggered arrangement of heat dissipation fins in the assembled stator by appropriately transposing the laminate.

[0026] All fins of a fin group with a lower number of fins in one laminate can be inserted between fins of a fin group with a higher number of fins in another laminate. Furthermore, a fin group with a higher number of fins in one laminate can have a central fin inserted between fins of a fin group with a lower number of fins in another laminate. This can help optimize the contact between the heat dissipation fins and the cooling fluid during motor operation.

[0027] In other embodiments, the laminate may have multiple sets of fins, each having the same number of fins. In this case, the staggered nature of the heat dissipation fins can be achieved by appropriately shifting the laminate sets. For example, consecutive laminate sets can be shifted such that a set of fins in one laminate set is circumferentially located between two adjacent fin sets in an adjacent laminate set, but circumferentially closer to another fin set than one fin set. This can be achieved by shifting the consecutive laminate sets by a value slightly different (slightly greater or slightly less) from half (or an odd multiple of) the angular distance between two adjacent fin sets in the laminate set. For example, consecutive laminate sets can be shifted by a value equal to half (or an odd multiple of) the angular distance between two adjacent fin sets plus or minus a value sufficient to ensure stator slot alignment (e.g., a value greater than 0 and less than or equal to the stator slot spacing or a multiple thereof). Therefore, when viewed axially through the stator core, the fin groups in the alternating laminates may appear skewed; that is, the lines extending through their centers may be offset relative to the axial direction (at a non-zero angle). This arrangement helps ensure that there is no straight (line-of-sight) path for air to flow axially across the entire stator core, or that this path is restricted. This can help introduce more turbulence than would otherwise be introduced, thus potentially increasing cooling capacity.

[0028] The heat dissipation fin assemblies within a laminate are preferably arranged such that the circumferential distance between two adjacent heat dissipation fin assemblies is greater than the circumferential width of the heat dissipation fin assembly. This allows the laminate to be rotated so that fin assemblies in one laminate assembly are circumferentially positioned between two adjacent fin assemblies in another laminate assembly. This can help create a gap between the heat dissipation fins in the axial direction through the motor. This, in turn, can help optimize the amount of cooling fluid in contact with the heat dissipation fins during motor operation.

[0029] Preferably, the heat dissipation fins within the laminate are spaced equidistantly in the circumferential direction. This helps ensure efficient use of material and optimal spacing of the heat dissipation fins in the assembled stator core.

[0030] Preferably, the heat dissipation fins within the laminate are arranged such that they extend into the corners of the imaginary rectangle containing the laminate. Since the laminate is often stamped from a single sheet of material with parallel sides, this allows the heat dissipation fins to be formed from areas of the raw material that would otherwise be discarded as waste.

[0031] When the laminate includes an annular body, the heat dissipation fins of the laminate can be arranged such that they fit within an imaginary rectangle (or square) having at least two sides whose lengths are substantially equal to the diameter of the annular body. This can be achieved by extending the heat dissipation fins into the corners of the rectangle. This can help ensure efficient use of material by allowing the heat dissipation fins to be formed without requiring an increase in the size of a single piece of material used to make the laminate.

[0032] In one embodiment, at least some of the laminates include four sets of heat dissipation fins. Preferably, one set of heat dissipation fins is radially opposite to another set of heat dissipation fins. Therefore, the center of one set of heat dissipation fins can be spaced approximately 90° from the center of the adjacent set of heat dissipation fins. This allows the heat dissipation fins to extend into each corner of the imaginary rectangle or square containing the laminates, thereby ensuring efficient use of material. In this case, the continuous laminate sets can be rotated up to 45° (or an odd multiple thereof), optionally by adding or subtracting an amount sufficient to ensure stator slot alignment.

[0033] In one embodiment, at least one set of heat dissipation fins has an angled bend. For example, in the case where the laminate comprises two fin groups with different numbers of fins, the fin group with the larger number of fins may have an angled bend (or multiple angled bends). This can be achieved, for example, by arranging the circumferentially outer heat dissipation fins in the fin group to be shorter in the radial direction than the intermediate fins in the same fin group and / or by arranging at least a portion of the peripheral connecting members (such as the circumferentially outer portion) at a non-zero angle relative to the circumferential direction (and radial direction). This can help ensure that a set of heat dissipation fins fits within an imaginary rectangle containing the laminate, thereby helping to ensure efficient use of material.

[0034] Preferably, each laminate has substantially the same shape. This can help simplify manufacturing because only one type of laminate needs to be made. In this case, the staggering of the heat dissipation fins can be achieved by rotating the laminates (i.e., rotating some laminates about their axes relative to other laminates). Thus, some of the laminates are rotated relative to the other laminates such that the heat dissipation fins in one laminate are inserted between two heat dissipation fins in a heat dissipation fin group in another laminate group.

[0035] However, some of the laminates may also have different shapes, and / or some laminates may have no heat dissipation fins or a reduced number of heat dissipation fins. This may be desirable, for example, when space constraints limit the area in which heat dissipation fins can be positioned.

[0036] Typically, a landing bar is used to position the stator of the motor within a stator frame. Therefore, the stator may include a landing bar slot for receiving the landing bar. Preferably, the landing bar slot is defined between fin assemblies of continuous laminates in the axial direction. This can be achieved by indexing the laminate or laminate components. This allows the landing bar slot to be provided without requiring additional features in the laminate, which can facilitate manufacturing.

[0037] Alternatively, the array of heat dissipation fins can be used to position the stator core within the stator frame without the need for positioning rods.

[0038] In any of the above arrangements, the stator core can be skewed if desired; that is, the stator slots can extend through the stator core at a (non-zero) angle relative to the axial direction. The amount of skew can be, for example, one or two stator slots or some other value. For example, skew can be achieved by appropriately rotating the continuous laminate or the assembly of laminates.

[0039] According to another aspect of the invention, a stator for a rotating electric motor is provided, the stator comprising a stack of stator laminates forming a stator core, wherein:

[0040] The laminate includes a plurality of heat dissipation fins, which are arranged in the form of at least one fin group comprising at least two fins.

[0041] The heat dissipation fins in the fin assembly are connected by peripheral connecting members; and

[0042] A heat dissipation fin in one laminate is inserted between two heat dissipation fins in a set of heat dissipation fins in another laminate.

[0043] According to other aspects of the invention, a rotary electric motor comprising a stator of any of the above forms is provided.

[0044] Corresponding methods can also be provided. Therefore, according to another aspect of the present invention, a method for manufacturing a stator for a rotating electric motor is provided, the method comprising the following steps:

[0045] Multiple stator laminates are formed, wherein the laminates include multiple heat dissipation fins, the multiple heat dissipation fins are arranged in the form of at least one fin group including at least two fins, and the heat dissipation fins in the fin group are connected by peripheral connecting members.

[0046] The laminates are arranged in the form of a laminate group including at least one laminate;

[0047] The laminate assembly is rotated such that a fin group in one laminate assembly is circumferentially located between two adjacent fin groups in an adjacent laminate assembly, and a heat dissipation fin in one laminate assembly is inserted between two heat dissipation fins in a heat dissipation fin group in another laminate assembly; and

[0048] The laminated components are stacked to form a stator core.

[0049] Features of one aspect of the invention can be applied to any other aspect. Any of the device features can be provided as method features, and vice versa.

[0050] In this specification, terms such as “radial,” “axial,” and “circumferential” are generally defined with reference to the rotating axis of the motor, unless otherwise stated. Attached Figure Description

[0051] Preferred embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, in which:

[0052] Figure 1 It is the radial cross-section passing through a portion of the rotating motor;

[0053] Figure 2 A stator laminate according to an embodiment of the present invention is shown;

[0054] Figure 3 This illustration shows how laminates can be stamped from a single sheet of metal.

[0055] Figures 4 to 8 This illustrates how consecutive laminates can be stacked to form a stator core in one embodiment;

[0056] Figure 9 This is an end view of the assembled stator core;

[0057] Figure 10 It is a 3D view of the stator core;

[0058] Figures 11 to 13 This illustrates another embodiment of how continuous laminates can be stacked to form a rotor core;

[0059] Figure 14 It is a 3D view of the assembled stator core;

[0060] Figure 15 A stator laminate in another embodiment is shown;

[0061] Figures 16 to 18 This illustrates another embodiment of how continuous laminates can be stacked to form a rotor core;

[0062] Figure 19 This is an end view of the assembled stator core;

[0063] Figure 20 It is a 3D view of the stator core;

[0064] Figure 21 Stator laminates in other embodiments are shown;

[0065] Figures 22 to 24 Other possible configurations of the stator laminate are shown;

[0066] Figure 25 and Figure 26 Another embodiment of the stator laminate and the assembled stator core is shown;

[0067] Figure 27 and Figure 28 A stator core according to other embodiments of the present invention is shown; and

[0068] Figure 29 This illustrates how the stator core can be assembled into the stator frame. Detailed Implementation

[0069] Figure 1 It is a radial cross-section passing through a portion of the rotating electric motor. The motor includes a rotor 2 located inside the stator 4, with an air gap between them. The rotor 2 is mounted on a shaft, with the axis of rotation indicated by the dashed line 6. The stator 4 includes a stator core 8 with slots on its inner circumference, in which stator windings are wound. The stator windings extend through the slots in a generally axial direction. End windings 10 extend from the stator slots and surround the outside of the stator core in a generally circumferential direction. The stator 4 is contained within a stator frame 12. Optionally, a positioning rod ( Figure 1 (Not shown) can be attached to the stator frame 12. A positioning rod extends axially through the motor and engages with the stator core 8 on its outer circumference to position the stator core within the stator frame. The positioning rod forms an air gap 14 between the stator core 8 and the stator frame 12. A shaft-driven fan 16 is located at the drive end of the motor to draw cooling air through the motor. Figure 1 As indicated by the arrow, the airflow passes primarily in the axial direction through the rotor / stator air gap and stator / frame air gap 14. If desired, an external, independently driven single or multiple fans or any other suitable device for drawing air through the motor can be used instead of a shaft-driven fan.

[0070] In such Figure 1 In rotary motors such as the rotary electric motor shown, the stator is often formed from multiple stator laminates. The laminates are often stamped from a single sheet of metal and then stacked together in the axial direction through the motor.

[0071] Figure 2 A stator laminate according to an embodiment of the present invention is shown. (Refer to...) Figure 2 The laminate 20 includes a generally annular body 22 having an inner edge 23 and an outer edge 24. A plurality of teeth 25 are provided on the radially inner side of the annular body 22. The teeth 25 define stator slots 26 designed to hold the stator windings.

[0072] exist Figure 2 In the arrangement, the laminate 20 includes a plurality of heat dissipation fins 28. The heat dissipation fins 28 extend radially outward from the outer edge 24 of the annular body 22. The heat dissipation fins are arranged in multiple groups, with fins in one group connected by peripheral connecting members 30. The peripheral connecting members 30 extend circumferentially between the radially outward portions of the fins in the group, with a gap between the peripheral connecting members 30 and the outer edge 24 of the annular body 22. Therefore, the gap or hole 32 is defined, on the one hand, between two adjacent fins 28 in the group, and on the other hand, between the outer edge 24 of the annular body 22 and the peripheral connecting member 30. The circumferential spacing between the fins in the group is approximately equal. Therefore, at least within one group, each hole 32 has approximately the same width in the circumferential direction.

[0073] In the illustrated arrangement, four sets of fins are provided. The fin sets are evenly spaced around the laminate in the circumferential direction. Therefore, the center of each fin set is approximately 90° apart from the adjacent set in the circumferential direction. Two sets have two fins connected by peripheral connecting members, while two sets have three fins connected by peripheral connecting members. In the three-fin sets, one fin is located at the center of the set in the circumferential direction, and two fins are located on either side of the center of the set in the circumferential direction. The two-fin sets have fins located on either side of the center of the set in the circumferential direction. Sets with the same number of fins are exactly opposite each other (spaced 180° apart).

[0074] In the illustrated arrangement, the circumferential distance between two adjacent fin groups is greater than the circumferential width of a fin group. Therefore, when assembling the stator, one laminate can be rotated relative to the other such that a fin group in one laminate is circumferentially positioned between two adjacent fin groups in the other laminate. The circumferential width of a set of three fins is greater than the circumferential width of a set of two fins. In this example, the set of three fins has a width extending through approximately 36°, and the set of two fins has a width extending through approximately 23°, although other values ​​can, of course, be used alternatively.

[0075] Within each set of fins, the peripheral connecting member 30 is generally in the arc form, extending in a generally circumferential direction to bridge the heat dissipation fins in the set. However, in the case of a set of three fins, the corners of the set are inclined, i.e., with a certain slope in both the circumferential and radial directions. This is achieved by arranging the outer fins (in the circumferential direction) to be shorter in the radial direction than the middle fins. In this case, the peripheral connecting member 30 includes inclined portions 34 located at each end adjacent to the outer fins in the circumferential direction. Each inclined portion 34 is radially angled or inclined inward as it approaches the outer fin in the circumferential direction. Specifically, the inclined portion 34 is substantially tangent to a point on the outer edge 24 of the annular body 22 located midway between the center of the fin set and the center of the adjacent fin set (i.e., a point approximately 45° circumferentially away from the center of the fin set). This arrangement can help reduce the amount of waste discarded during the fabrication of laminates.

[0076] Laminates used for stator cores are often stamped from a coil of electrical steel. Electrical steel is a commercially available product, typically supplied in coils of a certain width. Continuous laminates are often stamped from the coil using a stamping press. Therefore, each laminate is usually stamped from a region of the coil that is substantially square or rectangular in shape.

[0077] Figure 3 This schematic illustrates how laminates can be stamped from a single sheet of metal. (See reference) Figure 3 The outline of the laminate 20 is shown on a sheet of metal 36 from which the laminate is stamped. The laminate is adapted to be within an imaginary square of material with four sides, the length of which is approximately equal to the diameter of the annular body 22 of the laminate. Each fin assembly is located at a corner of this imaginary square. Thus, the fins 28 and the peripheral connecting members 30 are located in the portion of the material that would otherwise be discarded as scrap. Furthermore, in the three-fin assembly, the inclined portion 34 of the peripheral connecting members and the reduced height of the outer fins ensure that they remain within the envelope of the imaginary square. Therefore, this arrangement allows for the fabrication of heat dissipation fins from the portion of the material that would otherwise be discarded as scrap without increasing the overall envelope of the laminate on the sheet of metal.

[0078] During motor manufacturing, laminates are stacked together to form the stator core. Different laminates or different groups of laminates can be rotated relative to each other (indexing) to create heat dissipation fins with a desired pattern in the axial direction of the motor.

[0079] Figures 4 to 8 This illustrates one embodiment of how consecutive laminates can be stacked to form a stator core. (See reference...) Figure 4In the first step, N laminates 20 are aligned and stacked on top of each other to form a first core assembly (a set of laminates) 38 with a certain thickness. The number N can be any positive integer such as 1, 2, 3, 4, 5, 6, 7, 8, or larger. Typically, the number N is chosen to ensure that the heat dissipation fins have sufficient mechanical strength in the assembled stator. Since the heat dissipation fins are aligned, the core assembly includes heat dissipation fins with a thickness in the axial direction equal to the thickness of the N stator laminates and peripheral connecting members.

[0080] Reference Figure 5 In the next step, a second core group 40 is formed from a second set of laminates. The number of laminates in the second core group may be the same as or different from the number of laminates in the first core group. The second core group 40 is then rotated 45° relative to the first core group 38 about its axis. Thus, each fin group in one core group is circumferentially positioned between two fin groups in the other core group. The second core group 40 is then added to the first core group 38.

[0081] Reference Figure 6 In the next step, a third core assembly 42 is formed from the third set of laminates. The third core assembly is rotated 90° relative to the first core assembly about its axis (45° relative to the second core assembly). Therefore, the two fin groups in the third core assembly 42 are circumferentially aligned with the three fin groups in the first core assembly 38, and vice versa. Then, the third core assembly 42 is added to the first and second core assemblies.

[0082] Reference Figure 7 In the next step, a fourth core group 44 is formed from the fourth set of laminates. The fourth core group is rotated 135° relative to the first core group about its axis (90° relative to the second core group and 45° relative to the third core group). Therefore, the two fin groups in the fourth core group 44 are circumferentially aligned with the three fin groups in the second core group 40, and vice versa. However, the fin groups in the second and fourth core groups are circumferentially located between the fin groups in the first and third core groups, and vice versa. The fourth core group 44 is then added to the other core groups.

[0083] Reference Figure 8 In the next step, a fifth core group 46 is formed from the fifth set of laminates. The fifth core group is rotatably aligned with the first core group, or rotated 180°. Although these laminates are rotationally symmetrical in principle, there may be slight variations in the single piece of metal used to form the laminates in practice; therefore, a 180° rotation may be preferred to even out any inconsistencies. Then, the process is repeated. Figures 4 to 8 The steps shown involve adding a continuous core assembly rotated 45° until a stator core of the desired depth is obtained. The stator core is then assembled into components such as... Figure 1 Among the rotary motors shown are rotary motors and similar rotary motors.

[0084] exist Figures 2 to 8 In this arrangement, the stator has 48 stator slots, so the stator slot spacing (angular distance between adjacent slots) is 7.5°. In this configuration, the stator slots will align after a 45° rotation, as 45° is a multiple of the stator slot spacing. However, if necessary, the precise amount of rotation between the continuous core groups can be adjusted to ensure alignment when using different numbers of stator slots and / or different stator slot spacings.

[0085] Figure 9 This shows an end (axial) view of the assembled stator core 48. (Refer to...) Figure 9 As can be seen, the fins in one core group are circumferentially staggered relative to the fins in adjacent core groups. The fins in two fin groups within one core group are located between adjacent fins in three-fin groups within an adjacent core group. Additionally, slots 50 extending axially between the fin groups in each core group are provided. These slots can be used for positioning the positioning rods.

[0086] Figure 10 This is a perspective view of a stator core according to one embodiment. In this embodiment, the stator core 48 is formed of eight core groups (eight sets of laminates), each core group comprising four laminates. (See reference...) Figure 10 As can be seen, the fin groups in a core assembly are circumferentially located between two fin groups in adjacent core assemblies, such that when considering the path extending axially through the stator core, a fin group is encountered every other core assembly. Furthermore, the fins are circumferentially staggered, such that when considering the path extending axially through the stator core, a heat dissipation fin is encountered every three core assemblies. Therefore, each heat dissipation fin has an axial cooling channel leading to either side and a through space. This facilitates the transfer of heat from the stator core to the cooling fluid. In this embodiment, positioning grooves 50 extending axially between the fin groups in the various core assemblies are also provided.

[0087] When a rotating electric motor is running, the fan causes air to flow generally axially above the stator surface. This airflow moves between and around the heat dissipation fins. The airflow between and around the fins transfers heat from the stator core to the air. Furthermore, the staggered nature of the fins introduces turbulence into the airflow, which aids in cooling.

[0088] It has been found that the above-described heat sink fin arrangement offers several advantages over previously considered arrangements. First, the staggered nature of the heat sink fins facilitates heat transfer from the stator core, thereby aiding in stator cooling. Second, the peripheral connecting members increase the surface area exposed to cooling air, which also contributes to improved cooling. Third, the peripheral connecting members help provide structural rigidity, which can contribute to the mechanical properties of the motor. Fourth, each laminate has the same shape, and the staggered heat sink fins are achieved through appropriate rotation. This avoids the need to stamp different types of laminates, thus simplifying the manufacturing process. Fifth, from a material usage perspective, the laminate design is efficient because the fins and peripheral connecting members can be made from materials that would otherwise be scrap. Sixth, the laminate design allows for the inclusion of slots for positioning rods without requiring special features in the laminate. Therefore, the described arrangement allows for excellent thermal performance while providing excellent mechanical strength and cost savings in manufacturing.

[0089] In the above arrangement, eight positioning slots 50 are provided at spaced intervals around the stator. However, if desired, a different number of positioning slots can be obtained by appropriately rotating the laminate.

[0090] Figures 11 to 13 Another embodiment is shown, illustrating how consecutive laminates can be stacked to form a rotor core. In this embodiment, the laminates are indexed to provide four positioning bar slots.

[0091] Reference Figure 11 In the first step, N laminates are aligned and stacked on top of each other to form a first core group (a set of laminates) 52 with a certain thickness. The number N can be any positive integer such as 1, 2, 3, 4 or larger.

[0092] Reference Figure 12 In the next step, a second core group 54 is formed from the second set of laminates. The second core group is rotated about its axis by an angle of less than 45°, but sufficient to create a circumferential gap between the fin groups in the two core groups. Therefore, the circumferential distance between fin groups with the same number of fins in the corresponding core groups is less than the circumferential distance between fin groups with different numbers of fins. The second core group 54 is then added to the first core group 52.

[0093] Reference Figure 13 In the next step, a third core group 56 is formed from the third set of laminates. The third core group is rotated 90° relative to the first core group about its axis. Therefore, the two fin groups in the third core group 56 are circumferentially aligned with the three fin groups in the first core group 52, and vice versa. Then, the third core group 56 is added to the first core group and the second core group.

[0094] Still refer to Figure 13 In the next step, a fourth core assembly 58 is formed from the fourth set of laminates. The fourth core assembly is rotated 90° relative to the second core assembly about its axis (i.e., rotated relative to the first core assembly by an angle equal to the rotation angle of the second core assembly plus 90°). Therefore, the two fin groups in the fourth core assembly 58 are circumferentially aligned with the three fin groups in the second core assembly 54, and vice versa. Then, the fourth core assembly 58 is added to the others.

[0095] Then, repeat. Figures 11 to 13 The steps shown involve adding a continuous core assembly rotated at an appropriate angle until a stator core of the desired depth is obtained.

[0096] Figure 14 This is a perspective view of the stator core in the above embodiments. (Refer to...) Figure 14 The stator core 60 is formed from a continuous core assembly that has been rotated and axially stacked together. Figure 14 In this arrangement, the fins are staggered circumferentially, as in the previous embodiment. However, in this embodiment, four positioning rod slots 62 are provided. Figure 14 The image also shows a positioning rod 64 located in a positioning rod groove.

[0097] Figure 14 The diagram also illustrates how a skewed stator can be achieved through appropriate rotation of the laminates. Stator skew is a known technique that can help improve the harmonic performance of a motor. In a skewed stator, the stator slots (and thus the stator windings) extend in a direction slightly offset from the axial direction. Typically, the skew amount is one stator slot along the core length. In this case, each laminate (or core assembly) is slightly rotated relative to its adjacent laminate (or core assembly) to achieve the skew.

[0098] Figure 15 A stator laminate according to another embodiment of the present invention is shown. Figure 15 In this arrangement, each laminate includes a substantially annular body 22 with a plurality of stator slots 26. A plurality of heat dissipation fins 28 are provided extending radially outward from the annular body 22. As in the previous embodiment, the heat dissipation fins are arranged in groups, with fins in one group connected by peripheral connecting members 30. Holes 32 are defined between adjacent fins 28 in one group. However, in this embodiment, two groups have three fins connected by peripheral connecting members, while two groups have four fins connected by peripheral connecting members. The centers of each group of fins are spaced approximately 90° apart from adjacent groups in the circumferential direction, and groups with the same number of fins are radially opposite each other (spaced 180° apart).

[0099] Figures 16 to 18 This illustrates how continuous laminates can be stacked to form a rotor core in this embodiment. (Refer to...) Figure 16In the first step, N laminates are aligned and stacked on top of each other to form a first core group 66 with a certain thickness. The number N can be any positive integer such as 1, 2, 3, 4 or larger.

[0100] Reference Figure 17 In the next step, a second core group 68 is formed from the second set of laminates. The second core group is then rotated 45° relative to the first core group about its axis. Thus, each fin group in one core group is circumferentially positioned between two adjacent fin groups in the other core group. The second core group 68 is then added to the first core group 66.

[0101] Reference Figure 18 In the next step, a third core assembly 70 is formed from the third set of laminates. The third core assembly is rotated 90° relative to the first core assembly about its axis. Therefore, the four-fin group in the third core assembly is circumferentially aligned with the three-fin group in the first core assembly, and vice versa. The third core assembly 70 is then added to the first and second core assemblies.

[0102] Still refer to Figure 18 In the next step, a fourth core group 72 is formed from the fourth set of laminates. The fourth core group is rotated 135° relative to the first core group about its axis (90° relative to the second core group). Therefore, the three-fin group in the fourth core group is circumferentially aligned with the four-fin group in the second core group, and vice versa. However, the fin groups in the second and fourth core groups are circumferentially located between the fin groups in the first and third core groups, and vice versa. The fourth core group 72 is then added to the other core groups.

[0103] Then, repeat. Figures 16 to 18 The steps shown involve adding a continuous core assembly rotated 45° until a stator core of the desired depth is obtained.

[0104] Figure 19 An end view of the assembled stator core 74 is shown. It can be seen that the fins in one core group are circumferentially staggered relative to the fins in adjacent core groups. The fins in a three-fin group of one core group are located between adjacent fins in a four-fin group of an adjacent core group. Additionally, positioning grooves 76 extending in the axial direction between the fin groups in the various core groups are provided.

[0105] Figure 20 This is a perspective view of the stator core in this embodiment. (Refer to...) Figure 20 The stator core 74 is formed from a series of core groups that are rotated and axially stacked together. The fins are circumferentially staggered, such that a heat dissipation fin is encountered every three core groups when considering the path extending through the stator core in the axial direction. Therefore, each heat dissipation fin has an axial cooling channel leading to either side and a through space. This facilitates the transfer of heat from the stator core to the cooling fluid. Figure 20 The positioning rod 78 located in the positioning rod groove 76 is also shown. Figure 20 The stator in the middle is also skewed, which is achieved by properly rotating the laminate.

[0106] It has been discovered that, according to Figures 15 to 20 Increasing the number of fins per group as shown in the diagram can increase the total cooling capacity due to the increased number of fins, and / or improve the mechanical stability of the fins.

[0107] It will be understood that in the above embodiments, the laminate can be rotated by different amounts, for example, to match the above reference. Figures 11 to 13 The description is similar to that of providing different numbers of positioning rod slots.

[0108] Figure 21 Another stator laminate is shown in a different embodiment. In this embodiment, two sets of fins have four fins each, and two sets of fins have five fins each. As in the previous embodiment, the centers of each set of fins are spaced approximately 90° apart from adjacent sets in the circumferential direction, and sets with the same number of fins are spaced 180° apart. Multiple such laminates can be used to form the stator core in a manner similar to that described above in the previous embodiment. It should be understood that sets of fins with other numbers of fins are also possible.

[0109] Figures 22 to 24 Other possible configurations of the stator laminate, depending on the situation, are shown. In each case, a laminated stator core can be obtained by stacking multiple laminates with appropriate rotation. For example, where there is space constraint on one side of the stator core, a configuration can be used... Figure 23 or Figure 24 The arrangement.

[0110] Figure 25 A stator laminate according to another embodiment of the invention is shown. As in the previous embodiment, the laminate includes a substantially annular body 22 with a plurality of stator slots 26. In this embodiment, the stator has 60 stator slots, with a slot spacing of 6°. A plurality of heat dissipation fins 28 are provided extending radially outward from the annular body 22. The heat dissipation fins are arranged in four groups, with fins in one group connected by peripheral connecting members 30. Each group has six fins connected by peripheral connecting members. Holes 32 are defined between adjacent fins 28 in a group. The fins in the groups are spaced 90° apart around the periphery of the laminate. In this embodiment, each fin group is substantially identical to the other fin groups.

[0111] Figure 26 This shows how they can be stacked. Figure 25 The type of laminate shown is used to form the stator core. (Refer to...) Figure 26In this embodiment, eight laminates are stacked together to form a core assembly, with no transposition between the laminates. Although for ease of reference, Figure 26 Eight laminates in the core assembly are shown, but in practice, the number of laminates in a core assembly can be significantly more (in one embodiment, each laminate is approximately 0.5 mm thick). Multiple core assemblies are then stacked together to form a stator core 80. Each core assembly is rotated (about its axis) slightly more than 45° relative to the preceding core assembly. Because the rotation is only slightly more than 45°, each fin group in a core assembly is circumferentially located between two adjacent fin groups in an adjacent core assembly. Furthermore, alternating core assemblies have fin groups that are substantially aligned with each other. Thus, each core assembly encounters a set of fins when considering the path extending through the stator core in the generally axial direction.

[0112] However, because the rotation is slightly greater than 45°, the fin groups in the alternating core groups are not perfectly aligned with each other. Therefore, the fin groups in one core group are circumferentially located between two adjacent fin groups in an adjacent core group, but circumferentially closer to one group than the other. Thus, when viewed axially through the stator core, the fin groups in the alternating core groups appear skewed; that is, the lines extending through their centers are offset relative to the axial direction (by a non-zero angle).

[0113] In this embodiment, each core group is rotated approximately 45° + θ relative to the previous core group, where θ is an angle sufficient to ensure stator slot alignment. This ensures that the stator slots are continuous in the axial direction through the stator core, while allowing all laminates to have the same shape. In the example shown, there are 60 stator slots, and the spacing between the stator slots is approximately 6°. Therefore, in this example, each core group is rotated approximately 48° relative to the previous core group, 48° being a multiple of the stator slot spacing. However, it will be understood that skewness of the fin groups can also occur in the opposite direction, so the rotation between consecutive core groups can be approximately 42°. In another example, the stator can have 72 stator slots, in which case each core group can be rotated approximately 51° or 39° relative to the previous core group, or some other multiple of the stator slot spacing. It should be understood that these values ​​are given by way of example only, and other values ​​(e.g., by rotations of different numbers of stator slot spacings) are possible. Typically, each core group can be rotated relative to the previous core group by adding or subtracting half the angular distance between the two adjacent fin groups (or odd multiples thereof) to ensure that the stator slots are at least approximately aligned.

[0114] It can also adjust the precise amount of rotation between the continuous laminate and / or core assembly to achieve skewness through the stator slots of the stator core.

[0115] In this embodiment, the fin spacing (i.e., the angular distance between adjacent fins in the group) is selected such that at least some fins in one group of fins in a core group are inserted between two heat dissipation fins in one group of heat dissipation fins in a core group on the other side of an adjacent core group. In this embodiment, the fin spacing is approximately 7.5°, but other values ​​can of course be used alternatively. For example, a fin spacing approximately equal to the stator slot spacing can be selected.

[0116] By rotating the continuous core group by an angle of 45° + / - θ, the heat dissipation fins in one core group can be circumferentially positioned between two heat dissipation fins in a set of heat dissipation fins in the core group on the other side of the adjacent core group. Therefore, when considering the path extending axially through the stator core, the heat dissipation fin 28 in one core group coincides with the hole 32 between adjacent fins in a set of fins in the core group on the other side of the adjacent core group. Thus, the air passage extending axially through the hole 32 in a set of fins in one core group will encounter the fins in a set of fins in the core group on the other side of the adjacent core group (i.e., the two core groups are separated). Therefore, this arrangement allows for circumferentially staggered heat dissipation fins while using groups of fins with an equal number of fins.

[0117] therefore, Figure 26 The stator core is arranged such that air channels are provided between the fins, passing through the stator core in a generally axial direction. However, due to the staggered nature of the fins, this arrangement results in no straight (line-of-sight) path for air to flow through the entire stator core in the axial direction. The lack of a straight path means that more turbulence is introduced into the airflow than would otherwise be. This can help increase cooling capacity.

[0118] Figure 25 and Figure 26 A slot 31 for positioning "skew keys" during assembly is also shown. Skew keys are used to align the laminates as they are stacked together. Skew keys also control the stator slot skew angle of the stator core.

[0119] Figure 25 and Figure 26 The embodiment shown is designed for use without a positioning rod. Therefore, in this embodiment, the outer periphery of the peripheral connecting member 30 is arranged to engage with the stator frame. By avoiding the use of a positioning rod, a straight airflow path adjacent to the positioning rod through the stator core can be avoided. This helps ensure that the airflow encounters staggered heat dissipation fins, thereby contributing to improved cooling.

[0120] In this embodiment, the fins themselves are designed to hold the stator within the stator frame. For example, the stator can be assembled to the stator frame after heating to provide a small radial clearance during insertion. In this case, the resulting interference fit can generate radial loads through the heat dissipation fins. Alternatively, the stator can be cold-pressed into the frame. In this case, during the assembly process, in addition to the radial loads derived from the interference fit, axial loads will also be transferred to the fins. Therefore, it is necessary to ensure that the fins have sufficient mechanical strength to withstand the loads that may be applied to them. This can be achieved by appropriately selecting the number of fins per group (six in this example) and the number of laminates per core group (eight or more in this example). Of course, different numbers of fins per group and different numbers of laminates per core group can be used to suit various situations. Generally, the number of fins per group and the number of laminates per core group is a trade-off between cooling performance and mechanical strength (fewer fins per group and fewer laminates per core group result in a larger area for airflow, but lower mechanical strength).

[0121] In this embodiment, the outer fins in one group are tilted (i.e., at a non-zero angle to the radial direction). This can help provide additional strength to resist any rotational forces between the stator and the frame. However, it will be understood that the fins may have different spacing and / or different tilt angles.

[0122] It will be understood that other arrangements of stator fins are also possible. For example, different fin groups within the laminate can have different numbers of fins. Furthermore, the laminate can have more or fewer than four fin groups.

[0123] Figure 27 A stator core according to another embodiment of the invention is shown. The heat dissipation fins in the laminate are arranged in four groups, with the fins in one group connected by peripheral connecting members. In this embodiment, two groups have three fins, and two groups have four fins. The center of each fin group is spaced approximately 90° from the adjacent group in the circumferential direction, and groups with the same number of fins are radially opposite (spaced 180° apart). A hole is defined between adjacent fins in a group. In this example, the group with four fins has a larger hole at the center of the group than on either side. Positioning rods are provided between the fin groups. Figure 28 This shows how to assemble the positioning rod into the positioning rod slot.

[0124] Figure 29 This illustrates how the stator core can be assembled into the stator frame according to an embodiment of the present invention. (See also...) Figure 29The stator includes a stator core 82 and a stator winding 84. In this example, the stator frame 86 includes a positioning rod 88. The stator is axially inserted into the stator frame such that the positioning rod 88 is located in a positioning rod slot between fin assemblies on the stator core. In this embodiment, the positioning rod 88 is used to hold the stator core 82 within the stator frame 86.

[0125] In any of the above embodiments, a core assembly may include a single laminate or any other number of laminates. Each core assembly constituting the stator core may have the same number or a different number of laminates as the other core assemblies.

[0126] It should be understood that the embodiments of the present invention described above are merely illustrative and may be subject to variations in detail. For example, the laminate may include heat dissipation fins that are not connected by peripheral connecting members. Features of one embodiment may be used in conjunction with any other embodiment. For example, a set of fins in one embodiment may be used in combination with a set of fins in any other embodiment. Furthermore, the present invention is not limited to these embodiments, and other variations in detail will be apparent to those skilled in the art within the scope of the appended claims.

Claims

1. A stator for a rotating electric motor, the stator comprising a stack of stator laminates forming a stator core, wherein: The laminate includes a plurality of heat dissipation fins, which are arranged in the form of at least one fin group comprising at least two fins. The heat dissipation fins in the fin assembly are connected by peripheral connecting components; The laminates are arranged in the form of a laminate group including at least one laminate; In a laminate assembly, the fin groups are circumferentially located between two adjacent fin groups in an adjacent laminate assembly; as well as A heat sink fin in one laminate assembly is inserted between two heat sink fins in a heat sink fin assembly in another laminate assembly. At least some laminated components include multiple sets of heat dissipation fins. At least one set of fins has a different number of fins than another set of fins in the same laminate, and All the fins of the fin group with a lower number of fins in one laminate assembly are inserted between the fins of the fin group with a higher number of fins in another laminate assembly.

2. The stator according to claim 1, wherein, The laminate includes an annular body with an outer edge, and the heat dissipation fins extend radially outward from the outer edge.

3. The stator according to claim 1, wherein, A gap is provided between adjacent heat dissipation fins in the fin assembly for cooling fluid.

4. The stator according to claim 1, wherein, The peripheral connecting member connects the radially outward ends of the fins in the fin assembly.

5. The stator according to claim 1, wherein, The heat dissipation fins of one laminate assembly are staggered relative to the heat dissipation fins of another laminate assembly.

6. The stator according to claim 1, wherein, In the same laminate, the number of fins in one fin group is 1 more than the number of fins in another fin group.

7. The stator according to claim 1, wherein, A fin group with a higher number of fins in a laminate assembly has a central fin that is inserted between the fins in a fin group with a lower number of fins in another laminate assembly.

8. The stator according to claim 1, wherein, The continuous laminate groups are rotated such that the fin groups in one laminate group are circumferentially located between two adjacent fin groups in an adjacent laminate group, but are circumferentially closer to another fin group than one fin group.

9. The stator according to claim 1, wherein, The heat dissipation fins within the laminate are arranged such that the circumferential distance between two adjacent heat dissipation fins is greater than the circumferential width of the heat dissipation fins.

10. The stator according to claim 1, wherein, The heat dissipation fins in the laminate are spaced equidistantly in the circumferential direction.

11. The stator according to claim 1, wherein, The heat dissipation fins within the laminate are arranged such that they extend into the corners of an imaginary rectangle containing the laminate.

12. The stator according to any one of claims 1 to 11, wherein, The heat dissipation fins of the laminate are arranged such that they fit within an imaginary rectangle having at least two sides with a length substantially equal to the diameter of the annular body of the laminate.

13. The stator according to any one of claims 1 to 11, wherein, At least some of the laminates include four sets of heat dissipation fins.

14. The stator according to any one of claims 1 to 11, wherein, At least one set of heat dissipation fins has an inclined corner.

15. The stator according to any one of claims 1 to 11, wherein, The laminate comprises two fin groups with different numbers of fins, and the fin group with a larger number of fins has an inclined corner.

16. The stator according to any one of claims 1 to 11, wherein, The outermost heat dissipation fins in the fin group are shorter in the radial direction than the middle fins in the same fin group, and at least a portion of the peripheral connecting member is inclined relative to the circumferential direction.

17. The stator according to any one of claims 1 to 11, wherein, Each laminate has essentially the same shape.

18. The stator according to any one of claims 1 to 11, wherein, Some of the laminates in the laminate assembly are rotated relative to other laminate assemblies, such that a heat dissipation fin in one laminate assembly is inserted between two heat dissipation fins in a heat dissipation fin assembly in another laminate assembly.

19. The stator according to any one of claims 1 to 11, wherein, The laminate in the laminate assembly has rotatably aligned fins.

20. The stator according to claim 19, wherein, Multiple laminated components are rotated relative to each other.

21. The stator according to any one of claims 1 to 11, wherein the stator includes a positioning rod groove, wherein, The positioning groove is defined between the fin groups of the continuous laminate in the axial direction.

22. A method for manufacturing a stator for a rotating electric motor, the method comprising the steps of: Multiple stator laminates are formed, wherein the laminates include multiple heat dissipation fins, the multiple heat dissipation fins are arranged in the form of at least one fin group including at least two fins, and the heat dissipation fins in the fin group are connected by peripheral connecting members. The laminates are arranged in the form of a group of laminates including at least one laminate, wherein at least some of the laminate groups include multiple sets of heat dissipation fins, and at least one set of fins has a different number of fins than another set of fins in the same laminate. The laminate groups are rotated such that fin groups in one laminate group are circumferentially located between two adjacent fin groups in an adjacent laminate group, and heat dissipation fins in one laminate group are inserted between two heat dissipation fins in a heat dissipation fin group in another laminate group, and all fins of a fin group with a lower number of fins in one laminate group are inserted between fins of a fin group with a higher number of fins in another laminate group; and The laminated components are stacked to form a stator core.

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