Rotating electrical machine
By setting protrusions in the refrigerant flow path of the rotating motor and adjusting the spacing between adjacent protrusions, the problem of coolant difficulty in entering was solved, thus improving cooling performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2025-06-10
- Publication Date
- 2026-07-03
AI Technical Summary
In the prior art, the refrigerant flows through narrow sections between the convex parts in the oil circuit of the rotating motor, making it difficult for the coolant to enter, affecting the heat transfer effect and thus the cooling performance.
Multiple protrusions are set in the refrigerant flow path to ensure that the interval between adjacent protrusions is more than 15 times the length of the protrusion in the direction of protrusion. By stacking electromagnetic steel plates of different depths in the axial direction to form protrusions, the flow and stirring of cooling oil are promoted, and the heat transfer effect is improved.
By stirring the cooling oil, the cooling performance of the stator core was improved, and the heat transfer effect of the refrigerant in the stator core flow path was enhanced.
Smart Images
Figure CN224459403U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a rotary electric motor. Background Technology
[0002] Patent Document 1 discloses the following technology: In a motor, by combining electromagnetic steel plates with slightly misaligned holes in the oil passages of adjacent electromagnetic steel plates, unevenness is formed in the oil passages that serve as refrigerant flow paths, thereby improving heat transfer to the cooling oil that serves as refrigerant.
[0003] Existing technical documents
[0004] Patent documents
[0005] Patent Document 1: Japanese Patent No. 5221902
[0006] However, in the technology disclosed in Patent Document 1, the narrow space between the protrusions in the flow direction of the oil passage makes it difficult for the coolant to enter between the protrusions, which may consequently hinder heat transfer. Utility Model Content
[0007] This invention was made in view of the above-mentioned problems, and its purpose is to provide a rotary motor that can improve the heat transfer effect to the refrigerant flowing in the refrigerant flow path provided in the stator core and thus improve the cooling performance.
[0008] To solve the aforementioned problems and achieve the aforementioned objectives, the rotary motor of this utility model comprises: a stator having a stator core formed by stacking multiple electromagnetic steel plates along an axial direction and windings wound on the stator core; a rotor facing the stator radially; and a housing housing the stator and the rotor, wherein a refrigerant flow path for refrigerant flow is provided through the stator core in the axial direction. The rotary motor is characterized in that, within the refrigerant flow path, a plurality of protrusions are provided along the axial direction to narrow the width of the refrigerant flow path, and the distance between adjacent protrusions in the axial direction is more than 15 times the length of the protrusion in the protruding direction.
[0009] Effects of the utility model
[0010] The rotary motor of this invention has the following effect: it can improve the heat transfer effect of the refrigerant flowing in the refrigerant flow path provided in the stator core, thereby improving the cooling performance. Attached Figure Description
[0011] Figure 1 This is a cross-sectional view showing the schematic structure of the motor according to Embodiment 1.
[0012] Figure 2(a) is an enlarged view showing the main part of the first electromagnetic steel plate used in the stator core. Figure 2 (b) is an enlarged view showing the main part of the second electromagnetic steel plate used in the stator core.
[0013] Figure 3 This is an enlarged view of the main parts of the motor when it is cut along the axial direction, including the oil passages.
[0014] Figure 4 This is a cross-sectional view showing the schematic structure of the motor according to Embodiment 2.
[0015] Figure 5 (a) is an enlarged view showing the main part of the first electromagnetic steel plate used in the stator core of Embodiment 2. Figure 5 (b) is an enlarged view showing the main part of the second electromagnetic steel plate used in the stator core of Embodiment 2.
[0016] Figure 6 This is an enlarged view of the main parts of the motor when it is cut along a direction orthogonal to the radial and axial directions, including the oil passages.
[0017] Figure 7 (a) is an enlarged view showing the main part of the first electromagnetic steel plate used in the stator core of Embodiment 3. Figure 7 (b) is an enlarged view showing the main part of the second electromagnetic steel plate used in the stator core of Embodiment 3. Figure 7 (c) is an enlarged view showing the main part of the third electromagnetic steel plate used in the stator core of Embodiment 3.
[0018] Figure 8 This is an enlarged view of the main parts of the motor when it is cut along a direction orthogonal to the radial and axial directions, including the oil passages.
[0019] Explanation of reference numerals in the attached figures
[0020] 1 motor
[0021] 3 stators
[0022] 4 housings
[0023] 31 stator core
[0024] 35, 36 oil lines
[0025] 310A and 310C First Electromagnetic Steel Plates
[0026] 310B and 310D Second Electromagnetic Steel Plates
[0027] 310E Third Electromagnetic Steel Plate
[0028] The corresponding oil circuit sections of 350A, 350B, 360C, 360D, and 360E
[0029] 351, 361, 362 convex parts Detailed Implementation
[0030] (Implementation Method 1)
[0031] The following describes Embodiment 1 of the rotary motor of this utility model. It should be noted that this utility model is not limited to this embodiment.
[0032] Figure 1 This is a cross-sectional view showing the schematic structure of the motor 1 according to Embodiment 1. The motor 1 of Embodiment 1 consists of a rotor 2, a stator 3, and a housing 4. The rotor 2 and the stator 3 are housed inside the hollow interior of the housing 4. The motor 1 can be used as both an electric motor and a generator. Thus, the motor 1 of this embodiment is, for example, a rotary motor mounted on an electric vehicle, suitable for functioning as both an electric motor generating power for travel and a rotary motor generating electricity using regenerative torque.
[0033] The rotor 2 has a rotor core 20 fixed to the rotating shaft 21. The stator 3 is arranged radially outward from the rotor 2 at intervals. The stator 3 has a stator core 31 and stator coils 30 wound on the stator core 31. The stator core 31 is generally divided into a roughly annular core back 32 and a plurality of teeth 33. The core back 32 is provided with a plurality of oil passages 35 recessed radially inward from the outer circumference in the circumferential direction. The plurality of teeth 33 protrude radially inward from the inner circumferential direction of the core back 32. Grooves 34 are formed between adjacent teeth 33 in the circumferential direction to serve as spaces for receiving the stator coils 30. The oil passages 35 are arranged through the stator core 31 in the axial direction. The refrigerant flow path for cooling oil to flow in the axial direction of the stator core 31 is formed together with the inner circumferential surface of the housing 4. The cooling oil is the refrigerant for cooling the stator core 31 and the stator coils 30. The housing 4 is configured as a cylinder centered on the axis of the rotating shaft 21. It should be noted that the refrigerant is not limited to cooling oil; cooling water can also be used. Furthermore, the stator core 31 is constructed by stacking multiple electromagnetic steel plates in the axial direction (thickness direction).
[0034] Figure 2 (a) is an enlarged view showing the main part of the first electromagnetic steel plate 310A used in the stator core 31. Figure 2 (b) is an enlarged view showing the main part of the second electromagnetic steel plate 310B used in the stator core 31. Figure 2As shown in (a), the first electromagnetic steel plate 310A has a core-back portion 320A forming a core-back 32, a tooth portion 330A forming a tooth 33, a tooth groove portion 340A forming a tooth groove 34, and an oil passage portion 350A forming an oil passage 35. The oil passage portion 350A has a concave shape with a depth D1 extending radially inward from the outer periphery of the first electromagnetic steel plate 310A. Furthermore, as... Figure 2 As shown in (b), the second electromagnetic steel plate 310B has a core back portion 320B forming a core back 32, a tooth portion 330B forming a tooth 33, a tooth groove portion 340B forming a tooth groove 34, and an oil passage portion 350B forming an oil passage 35. The oil passage portion 350B is a recessed shape that is recessed radially inward from the outer periphery of the second electromagnetic steel plate 310B at a depth D2 that is shallower than the depth D1.
[0035] Furthermore, in the motor 1 of Embodiment 1, the stator core 31 is constructed by stacking a first electromagnetic steel plate 310A with a depth D1 that is deep in the oil passage equivalent portion 350A and a second electromagnetic steel plate 310B with a depth D2 that is shallow in the oil passage equivalent portion 350B in the thickness direction (axial direction).
[0036] Figure 3 This is an enlarged view of the main parts of motor 1, cut along the axial direction including the oil passage 35. (See diagram below.) Figure 3 As shown, when the first electromagnetic steel plate 310A and the second electromagnetic steel plate 310B are stacked in the axial direction to form the stator core 31, since the oil passage equivalent portion 350B of the second electromagnetic steel plate 310B is shallower than the oil passage equivalent portion 350A of the first electromagnetic steel plate 310A, a protrusion 351 is formed in the oil passage 35 such that the bottom surface of the oil passage equivalent portion 350B is higher in the radial direction than the bottom surface of the oil passage equivalent portion 350A. Furthermore, in the stator core 31, a plurality of protrusions 351 are provided in the oil passage 35 along the axial direction, and the protrusions 351 protrude in a way that narrows the width (depth) of the oil passage 35.
[0037] In general, when a narrow flow path transitions to a wider flow path via a step, flow stripping occurs, leading to reattachment downstream. Additionally, vortices are formed during this process, circulating and agitating the fluid. This type of flow has long been studied in fluid engineering as "post-step flow," a well-known phenomenon. Generally, in motor cooling, to suppress pressure loss, the practical range for the convex protrusion used to promote agitation is 1 / 2 to 1 / 4 of the flow path blocked, using a flow rate of approximately 200 to 1000 Reynolds numbers. Furthermore, within this range, the reattachment point, even at its furthest point, is at least 15 times the height of the protrusion (length in the protruding direction). That is, if a gap of at least 15 times the height of the protrusion is established beforehand, reliable reattachment can be achieved even as the refrigerant temperature changes from low to high temperatures and at various flow rates, thus improving cooling performance.
[0038] In the motor 1 of Embodiment 1, the second electromagnetic steel plate 310B is configured such that the interval L1 between adjacent protrusions 351 in the flow direction (axial direction) of the oil passage 35 is more than 15 times the depth difference h (depth D1 - depth D2) between the corresponding oil passage portions 350A and 350B, where the depth difference h between the corresponding oil passage portions 350A and 350B is the length (height) of the protrusions 351 in the protruding direction. As a result, cooling oil flowing in the oil passage 35 can easily enter the oil pocket formed between adjacent second electromagnetic steel plates 310B in the axial direction. Therefore, the cooling oil that has been stripped off at the rear end of the protrusion 351 re-attaches to the outer peripheral surface of the stator core 31, and the high-temperature cooling oil and low-temperature cooling oil near the outer peripheral surface of the stator core 31 are stirred. As a result, the heat transfer effect of the cooling oil flowing in the oil passage 35 can be improved, and the cooling performance can be improved. The protrusion 351 functions as a stirring component to stir the cooling oil flowing in the oil passage 35.
[0039] (Implementation Method 2)
[0040] The following describes Embodiment 2 of the rotary motor of this utility model. It should be noted that in Embodiment 2, descriptions of structures identical to those in Embodiment 1 are appropriately omitted.
[0041] Figure 4 This is a cross-sectional view showing the schematic structure of motor 1 according to Embodiment 2. In motor 1, which is a rotary electric machine according to Embodiment 2, as... Figure 4 As shown, the stator core 31 has multiple elongated oil passages 36 that extend radially from the core back 32 to the teeth 33. The multiple oil passages 36 are arranged to penetrate the stator core 31 in the axial direction, forming a flow path for cooling oil, which serves as a refrigerant, to flow.
[0042] Figure 5 (a) is an enlarged view showing the main part of the first electromagnetic steel plate 310C used in the stator core 31 of Embodiment 2. Figure 5 (b) is an enlarged view showing the main part of the second electromagnetic steel plate 310D used in the stator core 31 of Embodiment 2.
[0043] like Figure 5 As shown in (a), the first electromagnetic steel plate 310C has: a core back portion 320C forming a core back 32, a tooth portion 330C forming a tooth 33, a tooth groove portion 340C forming a tooth groove 34, and an oil passage portion 360C forming an oil passage 36. The oil passage portion 360C is an elongated hole shape that extends radially from the core back portion 320C to the tooth portion 330C of the first electromagnetic steel plate 310C. The oil passage portion 360C is arranged on a center line extending radially along the tooth portion 330C.
[0044] In addition, such as Figure 5 As shown in (b), the second electromagnetic steel plate 310D has: a core back portion 320D forming a core back 32, a tooth portion 330D forming a tooth 33, a tooth groove portion 340D forming a tooth groove 34, and an oil passage portion 360D forming an oil passage 36. The oil passage portion 360D is an elongated hole shape that is radially longer from the core back portion 320D to the tooth portion 330D of the second electromagnetic steel plate 310D. The oil passage portion 360D is disposed at a position offset to one side in the circumferential direction relative to the center line extending radially along the tooth portion 330D.
[0045] Furthermore, in the motor 1 of Embodiment 2, the stator core 31 is constructed by stacking a first electromagnetic steel plate 310C with a width W1 in the circumferential direction (short side direction) of the oil passage equivalent portion 360C and a second electromagnetic steel plate 310D with a width W2 in the circumferential direction (short side direction) of the oil passage equivalent portion 360C.
[0046] Figure 6 This is an enlarged view of the main part of the motor 1 when it is cut along a direction orthogonal to the radial and axial directions, including the oil passage 36. In the motor 1 of Embodiment 2, as... Figure 6As shown, the stator core 31 is constructed by stacking a first electromagnetic steel plate 310C and a second electromagnetic steel plate 310D in the axial direction (thickness direction). Consequently, the width of the oil passage equivalent portion 360D of the second electromagnetic steel plate 310D is narrower than the width of the oil passage equivalent portion 360C of the first electromagnetic steel plate 310C. Therefore, a protrusion 361 is formed within the oil passage 36, which is higher in the circumferential direction (in a direction orthogonal to the radial and axial directions) than the side surface of the oil passage equivalent portion 360C. Furthermore, in the stator core 31, a plurality of protrusions 361 protruding along the axial direction within the oil passage 36 are provided to narrow the width of the oil passage 36.
[0047] Furthermore, in the motor 1 of Embodiment 2, the second electromagnetic steel plate 310D is arranged such that the interval L2 between adjacent protrusions 361 in the flow direction (axial direction) of the oil passage 36 is more than 15 times the difference W3 (width W1 - width W2) between the length (width) of the protrusion 361 in the protruding direction, i.e., the width difference W3 between the oil passage equivalent portion 360C and the oil passage equivalent portion 360D. As a result, the cooling oil flowing in the oil passage 36 can easily enter the oil pocket formed between the adjacent second electromagnetic steel plates 310D in the axial direction. Therefore, the cooling oil that has been stripped from the rear end of the protrusion 361, which functions as a stirring member to agitate the cooling oil flowing in the oil passage 36, re-attaches on the surface of the oil passage 36 forming the stator core 31. The high-temperature cooling oil near this surface of the stator core 31 agitates the low-temperature cooling oil, thereby improving the heat transfer effect to the cooling oil flowing in the oil passage 36 and improving cooling performance.
[0048] (Implementation Method 3)
[0049] The following describes Embodiment 3 of the rotary motor of this utility model. It should be noted that descriptions of structures in Embodiment 3 that are the same as those in Embodiments 1 and 2 are appropriately omitted.
[0050] In the rotary electric motor 1 of Embodiment 3, similarly to the motor 1 of Embodiment 2, a plurality of [missing information] are provided in the circumferential direction of the stator core 31. Figure 4 The oil passage 36 is an elongated hole-shaped passage that extends radially from the core back 32 to the tooth 33, as shown.
[0051] Figure 7 (a) is an enlarged view showing the main part of the first electromagnetic steel plate 310C used in the stator core 31 of embodiment 3. Figure 7 (b) is an enlarged view showing the main part of the second electromagnetic steel plate 310D used in the stator core 31 of embodiment 3. Figure 7 (c) is an enlarged view showing the main part of the third electromagnetic steel plate 350E used in the stator core 31 of embodiment 3.
[0052] In the stator core 31 of Embodiment 3, similarly to the stator core 31 of Embodiment 2, in use Figure 7 The first electromagnetic steel plate 310C shown in (a) and Figure 7 As shown in (b), the second electromagnetic steel plate 310D is also used. Figure 7 The third electromagnetic steel plate 310E is shown in (c).
[0053] like Figure 7 As shown in (c), the third electromagnetic steel plate 310E has: a core back portion 320E forming a core back 32; a tooth portion 330E forming a tooth 33; a tooth groove portion 340E forming a tooth groove 34; and an oil passage portion 360E forming an oil passage 36. The oil passage portion 360E is an elongated hole shape that is radially longer from the core back portion 320E to the tooth portion 330E of the third electromagnetic steel plate 310E. The oil passage portion 360E is positioned offset circumferentially to the other side (opposite to the oil passage portion 360D of the second electromagnetic steel plate 310D) relative to the center line extending radially in the tooth portion 330E. It should be noted that, for example, the face and back of the second electromagnetic steel plate 310D can be flipped to be used as the third electromagnetic steel plate 310E.
[0054] Figure 8 This is an enlarged view of the main parts of the motor 1 when it is cut along a direction orthogonal to both the radial and axial directions, including the oil passage 36. In the motor 1 of Embodiment 3, as... Figure 8 As shown, the stator core 31 is constructed by stacking a first electromagnetic steel plate 310C, a second electromagnetic steel plate 310D, and a third electromagnetic steel plate 310E in the axial direction (thickness direction). Therefore, the width of the oil passage portion 360D of the second electromagnetic steel plate 310D is narrower than the width of the oil passage portion 360C of the first electromagnetic steel plate 310C. Consequently, a protrusion 361 is formed within the oil passage 36, where the side surface of the oil passage portion 360D is higher than the side surface of the oil passage portion 360C in the circumferential direction (orthogonal to the radial and axial directions). Similarly, since the width of the oil passage portion 360E of the third electromagnetic steel plate 310E is narrower than the width of the oil passage portion 360C of the first electromagnetic steel plate 310C, a protrusion 362 is formed within the oil passage 36, where the side surface of the oil passage portion 360E is higher than the side surface of the oil passage portion 360C in the circumferential direction (orthogonal to the radial and axial directions). Furthermore, protrusions 361 and 362 protrude in opposite directions in the circumferential direction so that they are different from each other relative to the oil passage 36. In addition, in the stator core 31, multiple protrusions 361 and 362 protrude along the axial direction within the oil passage 36 in a manner that narrows the width of the oil passage 36.
[0055] Furthermore, in the stator core 31 of Embodiment 3, the second electromagnetic steel plate 310D is arranged such that the interval L2 between adjacent protrusions 361 in the flow direction (axial direction) of the oil passage 36 is more than 15 times the difference W3 (width W1 - width W2) between the length (width) of the protrusion 361 in the protruding direction, i.e., the width difference W3 between the oil passage equivalent portion 360C and the oil passage equivalent portion 360D. Similarly, in the stator core 31 of Embodiment 3, the third electromagnetic steel plate 310E is arranged such that the interval L3 between adjacent protrusions 362 in the flow direction (axial direction) of the oil passage 366 is more than 15 times the difference W5 (width W1 - width W4) between the length (width) of the protrusion 362 in the protruding direction, i.e., the width difference W5 (width W1 - width W4) between the oil passage equivalent portion 360C and the oil passage equivalent portion 360E.
[0056] Therefore, the cooling oil flowing in the oil passage 36 can easily enter the oil pocket formed between adjacent protrusions 361 in the flow direction (axial direction) of the oil passage 36. Similarly, the cooling oil flowing in the oil passage 36 can easily enter the oil pocket formed between adjacent protrusions 362 in the flow direction (axial direction) of the oil passage 36. Therefore, at the rear ends of the protrusions 361 and 362, which function as stirring members to stir the cooling oil flowing in the oil passage 36, the flow of cooling oil is separated from the surface of the oil passage 36 forming the stator core 31 and re-attached. The high-temperature cooling oil and the low-temperature cooling oil near this surface of the stator core 31 are stirred, thereby improving the heat transfer effect of the cooling oil flowing in the oil passage 36 and improving the cooling performance.
Claims
1. A rotary electric motor, comprising: The stator has a stator core formed by stacking multiple electromagnetic steel plates along an axial direction and windings wound on the stator core. Rotor, the rotor being radially opposed to the stator; and A housing that houses the stator and the rotor. A refrigerant flow path for supplying refrigerant is provided that extends through the stator core in the axial direction. The rotary electric motor is characterized in that, Within the refrigerant flow path, a plurality of protrusions are provided along the axial direction to narrow the width of the refrigerant flow path, and the distance between adjacent protrusions in the axial direction is more than 15 times the length of the protrusion in the protruding direction.