rotating electrical machines

Abstract

To provide a cooling structure of a rotary electric machine capable of achieving high cooling performance.SOLUTION: A rotary electric machine 100 includes a rotor 1, a stator 2, and a coil 3 provided on at least one of these, including a coil conductor 31 wound around teeth 21b. The rotary electric machine 100 includes a spacer portion 42 that extends along a slot S formed between the teeth 21b and defines a gap G between turns by being inserted between the turns of the coil conductor 31 and a cooling medium supply unit 6 for circulating a cooling medium in the gap G. A notch 421 is provided in the middle of the spacer portion 42 so that the dimension of the spacer portion 42 in a width direction is relatively shortened.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a rotating electric machine. [Background technology]

[0002] 2. Description of the Related Art Machines that convert mechanical energy into electrical energy and vice versa and have rotating parts, such as motors and generators, are collectively called rotating electric machines, and are installed in a variety of devices.

[0003] A rotating electric machine includes a rotor and a stator. At least one of these has a plurality of teeth arranged in the circumferential direction, and the rotor rotates when power is supplied to coils formed by winding coil conductors around the teeth.

[0004] Generally, rotating electrical machines are provided with a cooling structure to release heat generated by power supply to the outside. For example, the cooling structure disclosed in Patent Document 1 provides a housing to house the coil conductors wound around each tooth, and injects a cooling fluid into the housing to directly cool the coil conductors. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2018 / 218314 Summary of the Invention [Problem to be solved by the invention]

[0006] For example, propulsion fan motors for aircraft (electric aircraft) require a high power density of approximately 5 to 10 kW / kg, and efforts are being made to miniaturize them as much as possible to achieve this. However, as rotating electrical machines become smaller, their surface area decreases along with their reduced volume, making it difficult for the generated heat to escape to the outside. Therefore, rotating electrical machines that achieve such high power densities require a cooling structure that can achieve particularly high cooling performance.

[0007] The present invention has been made to solve the above-mentioned problems, and has an object to provide a cooling structure for a rotating electrical machine that can achieve high cooling performance. [Means for solving the problem]

[0008] In order to achieve the above object, the present invention takes the following measures.

[0009] That is, the present invention provides a rotor, a stator, Stator a coil including a coil conductor wound around teeth provided on a rotor, the coil conductor comprising: a spacer portion extending along slots formed between the teeth and inserted between turns of the coil conductor to alternately separate the turns and define gaps between the turns; and a cooling medium supply portion supplying a cooling medium to a coil accommodating space formed in the slot between each tooth, The spacer portion does not protrude from a side surface of the coil conductor, and A notch is provided in the middle of the extension of the spacer portion, and in the width direction along the protruding direction of the spacer portion from the tooth, the dimension of the part of the spacer portion where the notch is formed is shorter than the dimension of the part of the spacer portion where the notch is not formed.As a result, the cooling medium flow path formed within the gap is expanded by the total area of ​​the notch, and when the cooling medium supply unit supplies cooling medium to the coil accommodating space, part of the cooling medium flows into the gap and circulates through the gap.

[0010] According to this configuration, gaps are defined between the turns of the coil conductor, through which the cooling medium flows, ensuring a sufficient contact area between the coil conductor and the cooling medium, thereby effectively cooling the coil. Furthermore, by providing a notch midway along the extension of the spacer portion, a locally wide area is formed midway along the gap, which serves as the cooling medium flow path. When the cooling medium passes through such a non-straight flow path, turbulence occurs in the flow of the cooling medium, stirring the cooling medium and improving the heat transfer coefficient. Furthermore, by providing a notch in the spacer portion, the contact area between the coil conductor and the spacer portion is reduced, thereby correspondingly increasing the contact area between the coil conductor and the cooling medium (i.e., the heat dissipation area). Both the improved heat transfer coefficient and the increased heat dissipation area lead to improved heat dissipation capacity, thereby achieving high cooling performance.

[0011] Preferably, in the rotating electric machine, a plurality of the notches are provided midway along the extension of the spacer portion. At least one of the corners of the cutout portion is rounded, and at least one of the corners of the cutout portion is tapered. It is characterized by:

[0012] This configuration creates multiple locally wide areas in the gaps that serve as the coolant flow paths, enhancing the agitation of the coolant and significantly improving the heat transfer rate (and thus the heat dissipation capacity). This results in particularly high cooling performance. By making at least one of the corners of the notch round, stagnation of the cooling medium is less likely to occur near the corner. If stagnation of the cooling medium occurs, there is a risk of a decrease in the heat transfer coefficient (and therefore the heat dissipation capacity), but by suppressing the occurrence of stagnation, the resulting decrease in heat dissipation capacity is suppressed. By making at least one of the corners of the notch tapered, it is possible to prevent the cooling medium from stagnating near the corner while ensuring the cooling medium is stirred at the corner. Therefore, it is possible to improve the heat transfer coefficient by stirring the cooling medium while preventing a decrease in the heat transfer coefficient due to stagnation, thereby achieving a balanced increase in heat dissipation capacity.

[0013] Preferably, in the rotating electric machine, the plurality of notches are arranged at a constant pitch.

[0014] With this configuration, the heat dissipation capacity is less likely to vary depending on the location, and the coil is cooled uniformly.

[0016] Preferably, in the rotating electric machine, each slot has a partition wall positioned approximately in the center of adjacent teeth, the coil conductor and the partition wall are spaced apart, and the space between the coil conductor and the partition wall forms part of the flow path of the cooling medium.

[0019] Preferably, in the rotating electric machine, a circulation flow path that connects one end side of the coil accommodating space with the other end side of the coil accommodating space, and the cooling medium introduced into the coil accommodating space from the one end side of the coil accommodating space flows out from the other end side of the coil accommodating space, and circulates to the one end side of the coil accommodating space by driving a pump inserted in the middle of the circulation flow path; It is characterized by: [Effects of the Invention]

[0021] According to the present invention, high cooling performance is achieved, so that the rotating electrical machine can be cooled sufficiently. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a vertical cross-sectional view of a rotating electrical machine according to an embodiment; [Figure 2] FIG. 2 is a cross-sectional view of the rotating electric machine as seen from the direction of arrow A in FIG. [Figure 3] FIG. [Figure 4] FIG. 4 is a perspective view showing a configuration example of a coil holding member. [Figure 5] FIG. 4 is a perspective view showing a configuration example of a coil holding member. [Figure 6] 10A and 10B are diagrams showing the results of simulation calculations of the heat dissipation capabilities achieved by the coil holding member according to the comparative example and the first and second coil holding members. [Figure 7] 5A and 5B are diagrams showing the shape of a gap formed by a coil holding member and first and second coil holding members according to a comparative example; [Figure 8] FIG. 10 is a diagram showing the results of a simulation of pressure loss when a cooling medium is circulated through a gap formed by the first and second coil holding members. [Figure 9] 10A and 10B are diagrams showing the shape of a cutout portion according to a modified example. [Figure 10] FIG. 10 is a diagram showing a part of a rotating electric machine according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0024] <1. Configuration of rotating electric machine> The configuration of a rotating electric machine according to an embodiment will be described with reference to Figs. 1 to 3. Fig. 1 is a longitudinal cross-sectional view of a rotating electric machine 100 according to an embodiment, taken along a plane perpendicular to the axial direction of a rotating shaft 101. Fig. 2 is a transverse cross-sectional view of the rotating electric machine 100 as viewed from the direction of arrow A in Fig. 1. Figs. 3(a) and 3(b) are both longitudinal cross-sectional views of a portion of the rotating electric machine 100, with Fig. 3(a) being a view of the rotating electric machine 100 taken at a position where the notch 421 is not provided in the spacer portion 42, and Fig. 3(b) being a view of the rotating electric machine 100 taken at a position where the notch 421 is provided in the spacer portion 42.

[0025] The rotating electric machine 100 is used, for example, as a propulsion fan motor for an aircraft (electric aircraft), and includes a rotor 1, a stator 2, a coil 3, a coil holding member 4, a space forming member 5, a cooling medium supply unit 6, etc.

[0026] (Rotor 1) The rotor 1 includes a cylindrical rotor core 11. Permanent magnets 12, which are divided into cylindrical or arch-shaped segments, are provided on the outer circumferential surface of the rotor core 11. A cylindrical through-hole that penetrates the rotor core 11 in the axial direction is provided at the radial center of the rotor core 11, into which a rotating shaft 101 is inserted. The rotating shaft 101 has an axial length longer than the rotor 1, and both ends of the rotating shaft 101 protrude beyond both ends of the rotor 1.

[0027] (Stator 2) The stator 2 is a substantially cylindrical member and is disposed so as to surround the outer peripheral surface of the rotor 1. The stator 2 includes a stator core 21. The stator core 21 is integrally formed to include a cylindrical yoke 21a and a plurality of teeth 21b that protrude radially inward from the inner peripheral surface of the yoke 21a. Each tooth 21b is formed over the entire axial length of the stator 2 from one end to the other. The plurality of teeth 21b are arranged at intervals along the circumferential direction, and gaps called slots S are formed between adjacent teeth 21b.

[0028] (Coil 3) The coil 3 includes a conductor (coil conductor) 31 wound around each tooth 21b and placed in the slot S. However, as will be described later, in this rotating electric machine 100, the coil conductor 31 is not wound directly around the teeth 21b, but is wound around the teeth 21b via a coil holding member 4, which will be described later.

[0029] The coil 3 is a three-phase coil including a U-phase coil, a V-phase coil, and a W-phase coil, and each end is drawn out radially from one axial end of the stator 2 to one end of a power line (not shown) for each phase. The other end of the power line for each phase is connected to a drive device, and when a three-phase AC voltage is applied from the drive device to the coil 3, the rotor 1 rotates and a rotational driving force is output from the rotary shaft 101.

[0030] (Coil holding member 4) The coil holding member 4 is a member that holds the coil 3. The coil conductor 31 is wound around the coil holding member 4 in advance, and the coil holding member 4 around which the coil conductor 31 is wound is attached to the tooth 21b, so that the coil conductor 31 is wound around the tooth 21b and arranged in the slot S. The configuration of the coil holding member 4 will be described later.

[0031] (Space forming member 5) The space forming member 5 is a member that forms a space (coil accommodating space) 50 that accommodates the coil 3 arranged in the slot S, and is configured to include a partition wall 51, a plurality of partition walls 52, a pair of lid portions 53a, 53b, and the like.

[0032] The partition wall 51 is a thin-walled cylindrical member and is disposed in the space between the rotor 1 and the stator 2. The partition wall 51 has approximately the same axial length as the stator 2, and is disposed so that its outer circumferential surface abuts entirely against the tips of the teeth 21b. This separates each slot S from the space on the rotor 1 side.

[0033] The partition wall 52 is a long, approximately plate-shaped member and is disposed in each slot S approximately at the center between adjacent teeth 21b. The longitudinal dimension of the partition wall 52 is approximately the same as the axial dimension of the stator 2, and the partition wall 52 extends from one end of the slot S to the other. The partition wall 52 is disposed so as to abut against the inner circumferential surface of the yoke 21a at one radial end of the stator 2 and abut against the outer circumferential surface of the bulkhead 51 at the other end. This divides each slot S into approximately two equal parts in the circumferential direction of the stator 2.

[0034] Each of the pair of lid portions 53a, 53b is an annular or disc-shaped member, and is disposed at each end in the axial direction of the stator 2 to close the open end of each slot S facing that end.

[0035] The bulkhead 51, the partition wall 52, and the pair of lids 53a, 53b form a coil accommodating space 50. That is, the coil conductor 31 arranged in each slot S is accommodated in the coil accommodating space 50 surrounded by the teeth 21b, the partition wall 52, the bulkhead 51, and the pair of lids 53a, 53b.

[0036] (Cooling medium supply section 6) The cooling medium supply unit 6 is an element that supplies a cooling medium to the coil accommodating space 50 formed in each slot S, and is configured to include a circulation flow path 61, a pump 62, a cooler 63, etc. Various fluids can be used as the cooling medium, but here, for example, oil (cooling oil) is used.

[0037] The circulation flow path 61 is a flow path for circulating the cooling medium, and one end thereof communicates with an inlet 531a provided in one lid portion 53a, and the other end thereof communicates with an outlet 531b provided in the other lid portion 53b. Each of the lid portions 53a, 53b has a branch flow path 532a (532b) that communicates with the inlet 531a (or outlet 531b) at one end and branches off midway to communicate with each coil accommodating space 50. In other words, the circulation flow path 61 communicates with each coil accommodating space 50 via the branch flow paths 532a, 532b, and the cooling medium introduced from the circulation flow path 61 via the inlet 531a flows into each coil accommodating space 50 via the branch flow path 532a. The cooling medium flowing out of each coil accommodating space 50 passes through the branch flow path 532b and is discharged to the circulation flow path 61 via the outlet 531b.

[0038] Both the pump 62 and the cooler 63 are inserted in the circulation flow path 61. When the pump 62 is driven, the cooling medium circulates through the circulation flow path 61, and the cooling medium flows through each coil accommodating space 50. The cooling medium circulating through the circulation flow path 61 is cooled by having heat removed by the cooler 63 provided in the path.

[0039] By circulating a cooling medium in the coil accommodating space 50, the coil 3 disposed therein is directly cooled by the cooling medium.

[0040] <2. Coil holding member 4> The configuration of the coil holding member 4 will be described with reference to Figures 4 and 5 in addition to Figures 1 to 3. Figures 4 and 5 are both perspective views showing examples of the configuration of the coil holding member 4.

[0041] The coil holding member 4 is a member that holds the coil 3, and is configured to include a base portion 41 and a spacer portion .

[0042] The base portion 41 is a member formed by forming a thin, strip-shaped member into a frame shape corresponding to the teeth 21b. Specifically, the base portion 41 has a pair of long portions 41a, 41a whose ends are connected via a pair of short portions 41b, and has a flat, generally rectangular shape as a whole. The dimension of each long portion 41a is approximately the same as the dimension of the tooth 21b in the extension direction, and the dimension of each short portion 41b is approximately the same as the dimension of the tooth 21b in the width direction.

[0043] The coil conductor 31 is wound around the base portion 41 (FIGS. 4(b) and 5(b)). Specifically, the coil conductor 31 is, for example, a strip-shaped conductor with a flat cross section whose thickness direction is smaller than its width direction, and is wound around the base portion 41 with its width direction aligned with the normal direction to the outer circumferential surface of the base portion 41. Here, a portion of the coil conductor 31 that goes around the base portion 41 (and thus the tooth 21b) is called "one turn." The turns may be continuous or discontinuous. For example, when a continuous coil conductor 31 is wound around the base portion 41, the turns are continuous. On the other hand, when the coil conductor 31 is formed by stacking frame-shaped conductor portions corresponding to one turn, the turns are discontinuous.

[0044] The spacer portion 42 is a long, plate-like member that protrudes from the outer surface of the long portion 41a of the base portion 41, with its length aligned along the extension direction of the long portion 41a of the base portion 41 and its width aligned along the normal to the outer surface of the base portion 41. The dimension of the spacer portion 42 in the extension direction is approximately the same as the dimension of the long portion 41a of the base portion 41, and the spacer portion 42 extends from one end to the other end of the long portion 41a. The widthwise dimension L0 of the spacer portion 42 (i.e., the protruding dimension from the base portion 41) can be determined as appropriate, but is preferably set to approximately 1 / 2 to 1 / 3 of the widthwise dimension of the coil conductor 31.

[0045] Each of the pair of long portions 41a, 41a of the base portion 41 is provided with multiple spacer portions 42, the number of which corresponds to the number of turns of the coil conductor 31. In the example shown in the figure, the number of turns of the coil conductor 31 is three, and each long portion 41a is provided with four spacer portions 42, which is this number of turns plus one, and is arranged at a regular interval (pitch). The pitch in this case is approximately the same as the thickness of the coil conductor 31.

[0046] The coil conductor 31 is wound around the base portion 41 with its widthwise ends inserted between the spacer portions 42 of adjacent rows, thereby being held between the spacer portions 42 of adjacent rows. Therefore, the spacer portions 42 are inserted between the turns of the coil conductor 31 wound around the base portion 41. By inserting the spacer portions 42 between the turns, a gap G corresponding to the thickness of the spacer portions 42 is defined between the turns (FIGS. 2 and 3). In other words, the spacer portions 42 are components that hold the coil conductor 31 and also define the gap G between the turns.

[0047] For example, when a continuous coil conductor 31 is wound around the base portion 41 (i.e., when each turn is continuous), the coil conductor 31 is wound around the base portion 41 while alternately passing through the long portion 41a and the short portion 41b. However, as described above, in the long portion 41a, the coil conductor 31 is wound so that its widthwise end is inserted between the spacer portions 42 of the adjacent stages. Here, each spacer portion 42 is provided in a horizontal position (i.e., a position in which the height position is constant throughout the extension direction), and the coil conductor 31 is guided by the spacer portions 42 in the long portion 41a and wound in a substantially horizontal position. Then, the coil conductor 31 that reaches the other long portion 41a via one short portion 41b is guided by the spacer portions 42 of the same height in the long portion 41a and continues to be wound in a substantially horizontal position. When the coil conductor 31 reaches the other short portion 41b, it is bent obliquely downward (or obliquely upward) and guided downward (or upward) from the previously wound coil conductor 31 by the thickness of the spacer portion 42 and the coil conductor 31 itself. Then, again, the pair of long portions 41a and one of the short portions 41b sandwiched between them are guided by the spacer portion 42 on the same level, and are wound in a substantially horizontal position. Thus, the coil conductor 31 is wound around the base portion 41 in a substantially horizontal position at least in each long portion 41a. Therefore, the gaps G defined between the turns extend substantially horizontally.

[0048] Each spacer portion 42 is provided with a notch 421 in the middle of its extension (that is, in the middle of the extension direction of the long portion 41a) so that the dimension of the spacer portion 42 in the width direction is relatively short.

[0049] The number, arrangement (the distance (pitch) between adjacent notches 421), shape, dimensions (lengthwise dimension L1, widthwise dimension L2) and the like of the notches 421 provided in the spacer portion 42 can be determined as appropriate as long as the functions of the spacer portion 42 (i.e., the function of holding the coil conductor wire 31 between the spacer portions 42 of adjacent rows and the function of defining the gap G between the turns) are not impaired. However, the "lengthwise direction" here refers to the extension direction of the spacer portion 42 (i.e., the extension direction of the long portion 41a), and the "width direction" refers to the direction in which the spacer portion 42 protrudes from the base portion 41.

[0050] For example, in the coil holding member 4 (4A) shown in FIG. 4, the number of notches 421 provided in the spacer portion 42 is five. The five notches 421 are arranged at a regular pitch. Each notch 421 has a right-angled corner. That is, each notch 421 is rectangular in plan view. The lengthwise dimension L1 (4A) of each notch 421 is approximately three-quarters of the lengthwise dimension of the non-notched portion (the portion of the spacer portion 42 that is not notched). The widthwise dimension L2 (4A) of each notch 421 is approximately the same as the widthwise dimension L0 (4A) of the spacer portion 42. That is, the notch 421 is formed by cutting out a portion of the spacer portion 42 across the entire width, and the widthwise dimension of the spacer portion 42 at the position where the notch 421 is formed is zero.

[0051] For example, in the coil holding member 4 (4B) shown in FIG. 5, the number of notches 421 provided in the spacer portion 42 is 14. Other than that, it is the same as the notches 421 provided in the coil holding member 4A shown in FIG. 4. That is, the 14 notches 421 are arranged at a constant pitch. Each notch 421 has a right-angled corner. The lengthwise dimension L1 (4B) of each notch 421 is approximately 3 / 4 of the lengthwise dimension of the non-notched portion. The widthwise dimension L2 (4B) of each notch 421 is approximately the same as the widthwise dimension L0 (4B) of the spacer portion 42. However, the widthwise dimension L0 (4B) of the spacer portion 42 of this coil holding member 4 (4B) is smaller than the widthwise dimension L0 (4A) of the spacer portion 42 of the coil holding member 4A shown in FIG. 4.

[0052] In the assembly process of the rotating electric machine 100, first, the coil conductor 31 is wound around the coil holding member 4 (FIGS. 4(b) and 5(b)). Specifically, the coil conductor 31 is wound around the base portion 41 so that its widthwise ends are inserted between the spacer portions 42 of adjacent rows. This results in the spacer portions 42 being inserted between the turns of the coil conductor 31 wound around the base portion 41, and a gap G corresponding to the thickness of the spacer portions 42 is defined between the turns, extending in the extension direction of the base portion 41 (FIGS. 2 and 3).

[0053] Then, the coil holding member 4 around which the coil conductor 31 is wound is attached to the tooth 21b. The base portion 41 has a frame shape corresponding to the tooth 21b, and when the base portion 41 is attached to the tooth 21b so as to surround the periphery of the tooth 21b, the inner circumferential surface of the base portion 41 contacts the outer circumferential surface of the tooth 21b entirely without any gap. In this state, the spacer portions 42 provided on each long portion 41a of the base portion 41 extend along the slot S.

[0054] In this way, the coil holding member 4 around which the coil conductor 31 is wound is attached to the tooth 21b, and the coil conductor 31 is wound around the tooth 21b via the coil holding member 4 and placed in the slot S. In this state, gaps G extending in the extension direction of the slot S are defined between the turns of the coil conductor 31.

[0055] <3. Cooling of Coil 3> The cooling mode of the coil 3 in the rotating electrical machine 100 will be described with continued reference to FIGS.

[0056] In the rotating electric machine 100, as described above, the space forming member 5 forms the coil accommodating space 50 that accommodates the coils 3 (specifically, the coil conductor 31) arranged in each slot S, and the cooling medium supply unit 6 supplies a cooling medium to the coil accommodating space 50 formed in each slot S. As a result, the coil conductor 31 arranged in the coil accommodating space 50 is directly cooled by the cooling medium.

[0057] Here, gaps G extending in the extension direction of the slots S are defined between the turns of the coil conductor 31 placed in the slots S. Therefore, a portion of the cooling medium supplied to the coil accommodating spaces 50 flows through these gaps G. That is, a portion of the cooling medium that flows into each coil accommodating space 50 from the circulation flow path 61 via the inlet 531a and the branch flow path 532a flows in from one end of the gap G in the extension direction, flows through the gap G, flows out from the other end in the extension direction, and is discharged to the circulation flow path 61 via the branch flow path 523b and the outlet 531b. The cooling medium flows through the gaps G formed between the turns of the coil conductor 31, ensuring a sufficient contact area between the coil conductor 31 and the cooling medium, and effectively cooling the coil 3.

[0058] In particular, here, a notch 421 is provided midway along the extension of the spacer portion 42 that defines the gap G, thereby effectively enhancing the ability to dissipate heat (heat dissipation capacity) from the coil 3. This will be explained with reference to Figures 6 and 7. Figure 6 shows the results of calculations, by simulation (thermal fluid analysis), of the heat dissipation capacity achieved by the coil holding member (first coil holding member) 4A according to the first embodiment shown in Figure 4 and the coil holding member (second coil holding member) 4B according to the second embodiment shown in Figure 5.

[0059] However, here, a coil holding member 9 that differs from the first coil holding member 4A only in that the spacer portion 42 does not have the notch portion 421 is designated as a "comparative example," and the heat dissipation capacity of each coil holding member 4A, 4B is shown as a ratio when the heat dissipation capacity achieved by the coil holding member 9 according to this comparative example is set to "1." Fig. 7 is a diagram schematically showing the shapes of the gaps G(9), G(4A), G(4B) (i.e., the shapes of the flow paths through which the coolant flows) formed by the coil holding member 9 according to the comparative example and the first and second coil holding members 4A, 4B, respectively.

[0060] As shown in Fig. 6, this simulation showed that the heat dissipation capacity of first coil holding member 4A was about 40% higher than that of coil holding member 9 according to the comparative example. Also, the heat dissipation capacity of second coil holding member 4B was about 70% higher than that of coil holding member 9 according to the comparative example. The reasons for this are thought to be as follows.

[0061] First, the temperature rise ΔT of the coil 3 is expressed by the following formula 1 using thermal resistance R and heat generation amount W. ΔT=R×W (Formula 1)

[0062] In other words, when the heat generation amount W is constant, the temperature rise ΔT is determined by the thermal resistance R. This thermal resistance R is expressed by the following (Equation 2) using the heat transfer coefficient h and the heat dissipation area A. R=1 / h×1 / A (Formula 2)

[0063] In other words, the larger the heat dissipation area A and the higher the heat transfer coefficient h, the smaller the thermal resistance R and the smaller the temperature rise ΔT. In other words, the heat dissipation capacity increases.

[0064] Here, the coil holding members 4A and 4B provided with the notched portion 421 have a larger heat dissipation area than the coil holding member 9 not provided with the notched portion 421. The reason for this is as follows.

[0065] That is, in the coil holding members 4A and 4B provided with the cutouts 421, the contact area between the coil conducting wire 31 and the spacer portion 42 is locally reduced at the portions where the cutouts 421 are provided ( FIG. 3( b)). For example, comparing the first coil holding member 4A and the coil holding member 9 according to the comparative example, which have the same width dimension L0 of the spacer portion 42, the coil holding member 4A provided with the cutouts 421 has a smaller contact area between the coil conducting wire 31 and the spacer portion 42 by the total area of ​​the regions cut out by the cutouts 421, compared to the coil holding member 9 without the cutouts 421. From another perspective, the provision of the cutouts 421 expands the gap G (4A), which serves as a flow path for the cooling medium, by the total area of ​​the cutout regions. Therefore, the contact area between the cooling medium and the coil conducting wire 31 (i.e., the heat dissipation area) is ensured to be larger by this total area. In this way, the heat dissipation area is increased by the total area of ​​the cutout regions due to the provision of cutout portions 421. As described above, the heat dissipation capacity is improved in accordance with the increase in the heat dissipation area.

[0066] 6, in this simulation, the improvement in heat dissipation capacity resulting from an increase in the heat dissipation area was approximately 20% to 2.5% for first coil holding member 4A and approximately 30% for second coil holding member 4B, and the improvement in heat dissipation capacity resulting from an increase in the heat dissipation area was greater for second coil holding member 4B than for first coil holding member 4A. This is thought to be because the widthwise dimension L0 of spacer portion 42 of second coil holding member 4B is smaller than that of first coil holding member 4A, and therefore the contact area between spacer portion 42 and coil conductor 31 is smaller (i.e., the heat dissipation area is larger).

[0067] Needless to say, the heat dissipation area can be increased by reducing the contact area between the spacer portion 42 and the coil conductor 31. It is preferable to adjust the dimension L0 of the spacer portion 42, the number, arrangement, shape, and dimensions L1 and L2 of the cutout portions 421, etc. so that the coil conductor 31 is held with the minimum necessary contact area. However, as will be described later, each of these values ​​also affects the heat transfer coefficient and pressure loss. Therefore, it is preferable to adjust each value while taking these effects into consideration so that the heat dissipation area is increased as much as possible.

[0068] Furthermore, the coil holding members 4A and 4B provided with the notched portion 421 have a higher heat transfer coefficient than the coil holding member 9 not provided with the notched portion 421. The reason for this is as follows.

[0069] That is, the greater the temperature difference (here, the temperature difference between the surface of the coil conductor 31 and the cooling medium nearby), the higher the heat transfer coefficient, but as the flow distance of the cooling medium increases, this temperature difference decreases and the heat transfer coefficient decreases. Once the flow distance of the cooling medium exceeds a predetermined distance called the inlet section, the heat transfer coefficient converges to a constant value.

[0070] Here, the gap G(9) formed by the coil holding member 9 without the notched portion 421 has a straight shape with a constant width (FIG. 7(a)). In contrast, the gaps G(4A), G(4B) formed by the coil holding members 4A, 4B with the notched portion 421 have relatively wide portions Gw appearing along their length. In other words, the gaps have a non-straight shape in which relatively wide portions Gw and relatively narrow portions Gn appear alternately, i.e., an uneven shape in plan view (FIGS. 7(b) and 7(c)).

[0071] When the cooling medium flows through these non-straight gaps G(4A), G(4B), turbulence occurs in the flow of the cooling medium, stirring the cooling medium. This promotes the exchange of positions between relatively high-temperature and relatively low-temperature portions of the cooling medium, lowering the temperature of the cooling medium near the surface of the coil conductor 31. This increases the flow distance to the region before passing through the inlet section, i.e., the region where the heat transfer coefficient is relatively high, improving the heat transfer coefficient. As described above, the improved heat transfer coefficient improves the heat dissipation capacity.

[0072] 6, in this simulation, the improvement in heat dissipation capacity resulting from an improvement in the heat transfer coefficient was about 20% for first coil holding member 4A and about 40% for second coil holding member 4B, and the improvement in heat dissipation capacity resulting from an improvement in the heat transfer coefficient was greater for second coil holding member 4B than for first coil holding member 4A. This is thought to be because second coil holding member 4B has a greater number of cutout portions 421 than first coil holding member 4A, resulting in a greater number of wide portions Gw appearing in gap G (4B), and therefore a greater cooling medium stirring effect.

[0073] In addition, in this simulation, the result was that the improvement in the heat transfer coefficient increases when the number of notched portions 421 is increased without changing the ratio between the length dimension L1 of the notched portions 421 and the length dimension of the non-notched portions. However, when the number of notched portions 421 is increased without changing the ratio between the length dimension L1 of the notched portions 421 and the length dimension of the non-notched portions, it is thought that once the number of notched portions 421 exceeds a certain upper limit, the improvement in the heat transfer coefficient decreases as the number of notched portions 421 increases (phantom line in FIG. 6). This is because as the number of notched portions 421 increases, the length dimension of the non-notched portions becomes shorter, making it easier for the cooling medium to stagnate in the wide portions Gw.

[0074] In this way, if the number of notches 421 is increased without changing the ratio of the lengthwise dimension L1 of the notched portion 421 to the lengthwise dimension of the non-notched portion, the improvement in the heat transfer coefficient is thought to initially increase and then decrease. Therefore, under given conditions, there is a range of the number of notches 421 that can achieve a heat transfer coefficient equal to or greater than a predetermined value. Therefore, it is preferable to specify the number of notches 421 within such a range. Specifically, for example, it is preferable to identify, through experiments or simulations, a range of the number of notches 421 that can achieve a heat transfer coefficient equal to or greater than an arbitrarily selected predetermined value, and set the number of notches 421 to a value selected from the identified range.

[0075] The pressure required to circulate the cooling medium through the gap G is determined by the pressure loss that occurs when the cooling medium flows through the gap G. To reduce the burden on the pump 62 and thereby achieve a more compact pump, a smaller pressure loss is preferable. As described above, the gaps G(4A), G(4B) formed by the coil holding members 4A, 4B in which the notches 421 are provided have a non-straight shape in which wide portions Gw and narrow portions Gn alternate. As described above, the gaps G(4A), G(4B) of this shape offer the advantages of an increased heat dissipation area and improved heat transfer coefficient. However, it appears to have a disadvantage in that the pressure loss is greater than that of the straight gap G(9). However, in reality, this is not necessarily the case.

[0076] 8 shows the results of a simulation of the pressure loss when the cooling medium is caused to circulate through the gaps G(4A) and G(4B) formed by the coil holding members 4A and 4B. However, here too, the pressure loss when the cooling medium is caused to circulate through each gap G(4A) and G(4B) is shown as a ratio when the pressure loss when the cooling medium is caused to circulate through the gap G(9) formed by the coil holding member 9 according to the comparative example is set to "1."

[0077] In this simulation, the cooling medium is assumed to be oil (cooling oil), and its density is 980 kg / m 3 ". The flow rate of the cooling medium delivered to the gaps G(9), G(4A), and G(4B) is set to "0.5 m / s." Under these conditions, the pressure loss in the gaps G(4A) and G(4B) formed by the coil holding members 4A and 4B is approximately 20% lower than the pressure loss in the gap G(9) formed by the coil holding member 9 according to the comparative example. The reason for this is believed to be as follows.

[0078] First, when the cooling medium flows through the gaps G(9), G(4A), and G(4B), a pressure loss ΔP1 due to friction (hereinafter referred to as "frictional pressure loss") occurs. Furthermore, when the cooling medium flows through the non-straight gaps G(4A) and G(4B) formed by the coil holding members 4A and 4B having the cutouts 421, a further pressure loss ΔP2 occurs as the cooling medium passes through the boundary between the narrow portion Gn and the wide portion Gw. That is, in the non-straight gaps G(4A) and G(4B), in addition to the frictional pressure loss ΔP1, a pressure loss ΔP2 due to the non-straight shape (hereinafter referred to as "geometric pressure loss") occurs. Needless to say, in the straight gap G(9) formed by the coil holding member 9 having no cutouts 421, the geometric pressure loss ΔP2 is zero.

[0079] The friction pressure loss ΔP1 is given by the following (Equation 3) using the friction coefficient λ, the length L of the flow path formed by the gap G, the characteristic length (average flow path width) d, the density ρ of the circulating cooling medium, and the flow velocity U of the cooling medium. ΔP1=λ(L / d)×(1 / 2)ρU 2 ...(Formula 3) However, the friction coefficient λ includes the inverse of the flow velocity (1 / U), and ΔP1 is proportional to the flow velocity U.

[0080] On the other hand, the geometric pressure loss ΔP2 resulting from one cutout portion 421 (i.e., the geometric pressure loss occurring when passing through one wide portion Gw) is given by the following (Equation 4) using the loss coefficient ζ, the density ρ of the circulating cooling medium, and the flow velocity U of the cooling medium. ΔP2=ζ×(1 / 2)ρU 2 ...(Formula 4) However, the loss factor ζ is at most "approximately 1".

[0081] Under the conditions used in this study, the geometric pressure loss ΔP2 calculated from the above (Equation 4) was approximately 0.1 kPa, while the friction pressure loss ΔP1 calculated from the above (Equation 3) was more than 100 times this geometric pressure loss ΔP2. In other words, under conditions such as the present conditions, where the coolant flow rate is relatively slow and the viscosity of the coolant is relatively high, the friction pressure loss ΔP1 becomes dominant, and the geometric pressure loss ΔP2 becomes small enough to be ignored compared to the friction pressure loss ΔP1.

[0082] According to the above formula (3), the friction pressure loss ΔP1 is proportional to the flow velocity U. Here, the gaps G(4A), G(4B) formed by the coil holding members 4A, 4B in which the notches 421 are provided have wide portions Gw in the middle, where the cross-sectional area of ​​the gaps G(4A), G(4B) (i.e., the flow path cross-sectional area of ​​the coolant) is locally widened. Therefore, the flow velocity of the coolant decreases when passing through the wide portions Gw. As a result, the friction pressure loss ΔP1, which is proportional to the flow velocity, decreases.

[0083] Thus, at least under conditions where the coolant flow rate is relatively slow and the coolant is oil (or a substance with similar density and viscosity), the geometric pressure loss ΔP2 resulting from the cutout 421 is sufficiently smaller than the frictional pressure loss ΔP1, and the effect of reducing the frictional pressure loss ΔP1 due to the formation of the wide portion Gw is significant. Therefore, the pressure loss in the gaps G(4A) and G(4B) formed by the coil holding members 4A and 4B is considered to be lower than the pressure loss in the gap G(9) formed by the coil holding member 9 according to the comparative example. However, because the relationship between the frictional pressure loss ΔP1 and the geometric pressure loss ΔP2 and their respective values ​​change depending on the conditions, such as the flow rate and type of coolant, the provision of the cutout 421 does not necessarily result in a reduction in pressure loss. However, at least under conditions similar to those described above, the provision of the cutout 421 is unlikely to result in a disadvantage such as increased pressure loss.

[0084] 8, in this simulation, the reduction in pressure loss was greater in gap G(B) formed by second coil holding member 4B than in gap G(A) formed by first coil holding member 4A. This is thought to be because second coil holding member 4B has a greater number of cutout portions 421 than first coil holding member 4A, and the widthwise dimension L0(4B) of spacer portion 42 is smaller, resulting in a greater reduction in the flow rate of the cooling medium.

[0085] In this simulation, the result was that the pressure loss decreases when the lengthwise dimension L1 of the cutout portion 421 is shortened without changing the ratio between the lengthwise dimension L1 of the cutout portion 421 and the lengthwise dimension of the non-cutout portion. However, if the lengthwise dimension L1 of the cutout portion 421 is further shortened without changing the ratio between the lengthwise dimension L1 of the cutout portion 421 and the lengthwise dimension of the non-cutout portion, once the dimension L1 falls below a certain lower limit, the effect of the geometric pressure loss ΔP2 becomes non-negligible, and the pressure loss is thought to begin to increase (phantom line in FIG. 8).

[0086] As described above, when the lengthwise dimension L1 of the notched portion 421 is reduced without changing the ratio between the lengthwise dimension L1 of the notched portion 421 and the lengthwise dimension of the non-notched portion, the pressure loss is thought to initially decrease and then increase. Therefore, under given conditions, there is a range of the lengthwise dimension L1 within which the pressure loss can be kept below a predetermined value. Therefore, it is preferable to set the lengthwise dimension L1 of the notched portion 421 within such a range. Specifically, for example, it is preferable to identify the maximum allowable pressure loss based on the capacity of the pump 62, and then identify the range of the dimension L1 within which the pressure loss can be kept below this maximum value through experiments or simulations, and set the lengthwise dimension L1 of the notched portion 421 to a value selected from the identified range.

[0087] <4. Effects> The rotating electric machine 100 according to the above embodiment includes a rotor 1, a stator 2, and a coil 3 including a coil conductor 31 wound around teeth 21b provided on at least one of the rotor 1 and stator 2, a spacer portion 42 extending along slots S formed between the teeth 21b and inserted between turns of the coil conductor 31 to define gaps G between the turns, and a coolant supply portion 6 for circulating a coolant through the gaps G. The rotating electric machine 100 is characterized in that a notch 421 is provided midway along the extension of the spacer portion 42 so that the dimension of the spacer portion 42 in the width direction is relatively short.

[0088] With this configuration, gaps G are defined between the turns of the coil conductor 31, through which the cooling medium flows. This ensures a sufficient contact area between the coil conductor 31 and the cooling medium, effectively cooling the coil 3. Furthermore, by providing the notches 421 midway along the extension of the spacer portion 42, a locally wide region Gw is formed midway along the gap G, which serves as the cooling medium flow path. As the cooling medium passes through this non-straight flow path, turbulence occurs in the flow of the cooling medium, stirring the cooling medium and improving the heat transfer coefficient. Furthermore, by providing the notches 421 in the spacer portion 42, the contact area between the coil conductor 31 and the spacer portion 42 is reduced, thereby correspondingly increasing the contact area between the coil conductor 31 and the cooling medium (i.e., the heat dissipation area). Both the improved heat transfer coefficient and the increased heat dissipation area lead to improved heat dissipation capacity, resulting in high cooling performance.

[0089] Furthermore, the rotating electric machine 100 according to the above embodiment is characterized in that a plurality of notches 421 are provided midway along the extension of the spacer portion 42.

[0090] With this configuration, multiple wide regions Gw are formed locally in the middle of the gap G, which serves as a flow path for the cooling medium. This enhances the agitation of the cooling medium, greatly improving the heat transfer coefficient (and thus the heat dissipation capacity). This results in particularly high cooling performance.

[0091] Furthermore, in the rotating electric machine 100 according to the above embodiment, the plurality of notches 421 are arranged at a constant pitch.

[0092] With this configuration, unevenness in heat dissipation capacity is less likely to occur depending on the location, and the coil 3 is cooled uniformly.

[0093] Furthermore, in the rotating electric machine 100 according to the above embodiment, it is preferable that the longitudinal dimension L1 of the cutout portion 421 is specified within a range such that the pressure loss when circulating the cooling medium through the gap G is equal to or less than a predetermined value.

[0094] According to this configuration, the pressure loss when the cooling medium is circulated through the gap G is equal to or less than a predetermined value, so that the load on the mechanism for circulating the cooling medium (for example, the pump 62, etc.) can be reduced.

[0095] <5. First Modification> The shape of the notch 421 provided in the spacer 42 is not limited to that exemplified in the above embodiment. That is, in the above embodiment, the corners of the notch 421 are right-angled and the notch 421 is rectangular in plan view, but the shape of the notch 421 is not limited to this.

[0096] For example, as in the cutout portion 421 shown in FIG. 9(b), each corner 1211u, 1211d may be rounded. Alternatively, as in the cutout portion 421 shown in FIG. 9(c), each corner 1211u, 1211d may be tapered (C-chamfered). Alternatively, as in the cutout portion 421 shown in FIG. 9(d), the upstream corner (upstream corner) 1211u with respect to the flow of the cooling medium may be rounded, and the downstream corner (downstream corner) 1211d with respect to the flow of the cooling medium may be tapered. Alternatively, as in the cutout portion 421 shown in FIG. 9(e), the upstream corner 1211u may be rounded, and the downstream corner 1211d may be right-angled. Further, for example, like a cutout portion 421 shown in FIG. 9(f), an upstream corner portion 1211u may be tapered and a downstream corner portion 1211d may be right-angled.

[0097] The shape of the corners 1211u and 1211d of the cutout 421 affects the likelihood of stagnation Q occurring. That is, if the corners 1211u and 1211d of the cutout 421 are, for example, right-angled ( FIG. 9(a) ), the flow path width changes abruptly at the boundary between the wide portion Gw and the narrow portion Gn. Then, depending on the conditions, the coolant flow may separate into a straight flow and a flow that stagnates in the wide portion Gw at the point where it flows from the narrow portion Gn to the wide portion Gw. Similarly, the coolant flow may separate into a flow that stagnates in the wide portion Gw and a flow that stagnates in the wide portion Gw at the point where it flows from the wide portion Gw to the narrow portion Gn. When these flow separations occur, stagnation Q of the coolant flow occurs near the corners 1211u and 1211d. In such a stagnation Q, the flow path of the cooling medium becomes close to zero, which reduces the heat transfer coefficient and the effective heat dissipation area, which may result in a decrease in heat dissipation capacity.

[0098] 9(b) to 9(f), when at least one of the corners 1211u and 1211d is rounded or tapered, the change in flow path width is gradual, so that flow separation is unlikely to occur at the corners 1211u and 1211d, and stagnation Q of the cooling medium is unlikely to occur near the corners 1211u and 1211d. Therefore, a decrease in heat dissipation capacity due to the occurrence of stagnation Q is suppressed.

[0099] The effect of suppressing the occurrence of stagnation Q is highest when the corner portions 1211u, 1211d are rounded, followed by a tapered shape, and lowest by a right-angled shape. Therefore, from the viewpoint of suppressing the occurrence of stagnation Q, a rounded shape is most preferable as the shape of the corner portions 1211u, 1211d, followed by a tapered shape, and then a right-angled shape.

[0100] Flow separation is more likely to occur at the upstream corner 1211u than at the downstream corner 1211d, and stagnation Q is particularly likely to occur near the upstream corner 1211u. Therefore, it is also preferable that at least the upstream corner 1211u be rounded or tapered.

[0101] The shape of the corners 1211u and 1211d also affects the ability to agitate the cooling medium. That is, the cooling medium flowing through the gap G is significantly disturbed and agitated when it passes through the corners 1211u and 1211d of the cutout 421, and the right-angled shape has the greatest effect of agitating the cooling medium, followed by the tapered shape, and the rounded shape has the least effect. As described above, the greater the agitation of the cooling medium, the higher the heat transfer coefficient and the improved heat dissipation capacity. Therefore, from the perspective of agitating the cooling medium, the right-angled shape is the most preferable shape for the corners 1211u and 1211d, followed by the tapered shape, and then the rounded shape.

[0102] In particular, by making the corners 1211u and 1211d tapered, it is possible to suppress the occurrence of stagnation Q of the cooling medium near the corners while also ensuring the effect of stirring the cooling medium at the corners 1211u and 1211d. Therefore, it is possible to improve the heat transfer coefficient by stirring the cooling medium while suppressing the decrease in the heat transfer coefficient caused by stagnation Q, thereby achieving a well-balanced improvement in heat dissipation capacity.

[0103] The cooling medium is particularly likely to be agitated when passing through downstream corner portion 1211d. Therefore, in order to agitate the cooling medium effectively, it is preferable that at least downstream corner portion 1211d be formed into a right-angled or tapered shape.

[0104] Furthermore, the shape of the corners 1211u and 1211d also affects the likelihood of bubble generation, pressure loss, and the like. For example, tapered and rounded corners 1211d and 1211d are less likely to generate bubbles and have lower pressure loss than right-angled corners 1211u and 1211d. Therefore, in order to suppress bubble generation or reduce pressure loss, it is preferable that the corners 1211u and 1211d be rounded or tapered.

[0105] Needless to say, the shapes of the corners 1211u and 1211d may be other than a right angle, a rounded shape, a tapered shape, etc. Furthermore, the shapes of the upstream corner 1211u and the downstream corner 1211d may be different, and shapes may be combined freely.

[0106] <6. Second Modification> In the above embodiment, the spacer portion 42 is provided on the base portion 41, and the coil holding member 4 is configured to include these portions 41, 42. However, the manner in which the spacer portion 42 is provided is not limited to this. For example, as shown in FIG. 10 , the spacer portion 521 may be provided on the partition wall 52. In this case, the configuration of the spacer portion 521 may be the same as that of the spacer portion 42 provided on the base portion 41.

[0107] When the partition wall 52 is provided with the spacer portion 521, the coil holding member 4 may be omitted. However, as shown in Fig. 10, if the coil holding member 4 is provided with the spacer portion 42 and the partition wall 52 is provided with the spacer portion 521, the coil conductor 31 is held by the spacer portions 42, 521 at both widthwise ends, and therefore the coil conductor 31 is maintained in a flatter position than when the coil conductor 31 is held only at one widthwise end. This maintains stable heat dissipation performance and prevents an increase in pressure loss in the flow path formed by the gap G.

[0108] Furthermore, by providing the spacer portion 42 on the coil holding member 4 and the spacer portion 521 on the partition wall 52, the shape of the flow path formed by the gap G can be arranged in various ways. For example, by arranging the notches provided in the spacer portions 42, 521 in the same phase (i.e., by providing the notches in opposing positions), it is possible to increase the difference between the wide portion Gw and the narrow portion Gn in the flow path formed by the gap G. Furthermore, by shifting the arrangement of the notches provided in the spacer portions 42, 521 by half a phase, it is possible to make the flow path formed by the gap G serpentine.

[0109] <7.Third Modification> The number, arrangement, shape, dimensions L1, L2, etc. of the notches 421 provided in the spacer portion 42 are not limited to those exemplified in the above embodiment.

[0110] For example, the number of notches 421 provided in the extending portion of the spacer portion 42 may be one. When one notch 421 is provided, it is also preferable to provide it near the center in the extending direction of the spacer portion 42. Furthermore, notches may be provided not only in the extending portion of the spacer portion 42 but also at the end of the spacer portion 42 in the extending direction.

[0111] Furthermore, for example, the notches 421 do not necessarily need to be arranged at a constant pitch, and the pitch may be narrower toward the center of the extension direction of the spacer portion 42, for example.

[0112] Furthermore, for example, the dimension L2 of the cutout portion 421 in the width direction may be smaller than the dimension of the spacer portion 42 in the width direction.

[0113] <8. Fourth Variation> The number, arrangement, shape, lengthwise dimension, widthwise dimension L0, etc. of the spacer portions 42 provided on the base portion 41 are not limited to those exemplified in the above embodiment.

[0114] For example, in the above embodiment, each long portion 41a is provided with spacer portions 42 whose number is equal to the number of turns of the coil conductor 31 plus one, and spacer portions 42 are arranged on both sides of all turns of the coil conductor 31. However, the number of spacer portions 42 may be equal to or less than the number of turns. For example, the number of spacer portions 42 may be less than the number of turns, and spacer portions 42 may be inserted between turn bundles each consisting of a plurality of turns, thereby defining gaps G between the turn bundles.

[0115] Furthermore, for example, in the above embodiment, the plurality of spacer portions 42 provided on each long portion 41a are arranged at a constant pitch, but the pitch between the spacer portions 42 does not have to be constant.

[0116] Furthermore, for example, in the above embodiment, the dimension of the spacer portion 42 in the longitudinal direction is approximately the same as the dimension of the long portion 41 a, but the dimension of the spacer portion 42 in the longitudinal direction may be shorter than the dimension of the long portion 41 a. In other words, the spacer portion 42 does not necessarily have to extend from one end to the other end of the long portion 41 a.

[0117] Furthermore, the spacer portion 42 may be formed from a single integrally formed part, or may be formed by combining a plurality of divided parts. In the latter case, the spacer portion 42 may be formed by arranging a plurality of parts separately, or may be formed by connecting a plurality of parts.

[0118] The thickness of the spacer portions 42 can also be determined as appropriate. However, the smaller the thickness of the spacer portions 42 (i.e., the thinner the spacer portions 42), the smaller the thickness of the gap G defined between the turns of the coil conductor 31 (i.e., the thickness of the flow path for the cooling medium). As the thickness of the flow path decreases, the thermal boundary layer of the cooling medium flowing therethrough becomes thinner, and the thickness of the relatively low-temperature layer of the cooling medium flowing through the flow path becomes thinner. The thinner the thermal boundary layer, the greater the temperature difference between the surface of the coil conductor 31 and the cooling medium nearby, and the better the heat transfer coefficient. In other words, the thinner the thickness of the spacer portions 42, the better the heat transfer coefficient. Therefore, it is preferable that the thickness of the spacer portions 42 be as small as possible, as long as the functions of the spacer portions 42 (i.e., the function of holding the coil conductor 31 between the spacer portions 42 of adjacent rows and the function of defining the gap G between the turns) are not impaired. As an example, the thickness of the spacer portion 42 can be set to about 1 / 2 to 1 / 10 of the thickness of the coil conductor wire 31.

[0119] <9. Other variations> In each of the above embodiments, the configurations of the rotor 1, stator 2, coil 3, etc. are not limited to those exemplified above. For example, the rotor 1 and / or the stator 2 may have a structure in which multiple electromagnetic steel plates are stacked in the axial direction. Also, for example, the rotor may be configured as an outer rotor type disposed outside the stator. Also, for example, teeth may be formed on the rotor side.

[0120] In each of the above embodiments, the present invention has been exemplified as being applied to a rotating electric machine 100 used as a fan motor for propelling an aircraft, but it goes without saying that the present invention can be applied to various other rotating electric machines.

[0121] Other configurations can also be modified in various ways without departing from the spirit of the present invention. [Explanation of symbols]

[0122] 1 rotor 2 stator 3 coils 31 Coil conductor 4 Coil holding member 41 Base 42 Spacer part 421 Notch 5 Space forming members 51 Bulkhead 52 Partition Wall 53a,53b Lid 50 Coil storage space 6 Coolant supply section 61 Circulation flow path 62 Pump 63 Cooler 100 Rotating Electric Machine

Claims

1. A rotating electric machine including a rotor, a stator, and a coil including a coil conductor wound around teeth provided on the stator, spacer portions extending along slots formed between the teeth and inserted between turns of the coil conductor to alternately separate the turns and define gaps between the turns; a cooling medium supply unit that supplies a cooling medium to a coil accommodating space formed in a slot between each tooth; Equipped with The spacer portion does not protrude from a side surface of the coil conductor, and a notch portion is provided midway along the extension of the spacer portion, In the width direction of the spacer portion along the direction in which the spacer portion protrudes from the teeth, The dimensions of the portion where the notch is formed are the same as the dimensions of the portion where the notch is not formed of the spacer portion. The dimension of the cooling medium passage formed in the gap is shorter than the dimension of the front portion. The total area of ​​the notch is expanded by When the cooling medium supply unit supplies the cooling medium to the coil accommodating space, a portion of the cooling medium flows into the gap and circulates through the gap.

2. 2. The rotating electric machine according to claim 1, a plurality of the notches are provided midway along the extension of the spacer portion; At least one corner of the cutout portion is rounded, At least one corner of the cutout portion is tapered. A rotating electric machine characterized by:

3. 3. The rotating electric machine according to claim 2, The plurality of cutouts are arranged at a constant pitch. A rotating electric machine characterized by:

4. 4. A rotating electric machine according to claim 1, Each slot has a partition wall disposed at approximately the center of adjacent teeth, The coil conductor and the partition wall are spaced apart, and a space between the coil conductor and the partition wall forms a part of a flow path of the cooling medium. A rotating electric machine characterized by:

5. 5. A rotating electric machine according to claim 1, a circulation flow path that connects one end side of the coil accommodating space with the other end side of the coil accommodating space, The cooling medium introduced into the coil accommodating space from one end side thereof flows out from the other end side thereof, and is circulated to the one end side of the coil accommodating space by driving a pump inserted in the middle of the circulation flow path. A rotating electric machine characterized by:

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