Stator, rotating electrical machine, stator manufacturing device, and stator manufacturing method

Abstract

A stator (50) has: a first resin part (40A) in which a resin member (R) fills a void part (V) extending in the axial direction along a winding (30) in a slot (20S) between both axial ends of an iron core (20); and second resin parts (40B1, 40B2) in which the resin member (R) seals a coil end part (30E). Wiring parts (25B, 30A, 35A) connected to a end part of the winding (30) are arranged so as to be positioned within a first range set in a plane perpendicular to the axial direction from a cross section perpendicular to the axial direction of the first resin part (40A) on the other axial side of the iron core (20), and the second resin part (40B2) on the other axial side is oriented within the first range, with the axial direction as the orientation direction.

Description

Stator, rotating electric machine, stator manufacturing device, and stator manufacturing method

[0001] The present disclosure relates to a stator, a rotating electric machine, a stator manufacturing apparatus, and a stator manufacturing method.

[0002] The operating principle of a rotating electric machine is that a rotational force is generated in a shaft press-fitted into a rotor core in response to commands from a control device with an inverter circuit. At this time, the approximately annular stator deforms due to electromagnetic forces generated between the stator and the rotor, causing the stator to vibrate in synchronization with the rotation of the rotor. When this stator vibration is transmitted to the frame into which the stator is press-fitted, shrink-fitted, or otherwise, it generates vibration and noise in the rotating electric machine.

[0003] To suppress vibration in such rotating electric machines, a structure has been used in which the stator windings are solidified with a resin material by insert molding, thereby increasing the stator's annular rigidity, preventing stator deformation, and suppressing vibration in the rotating electric machine. However, the ends of the stator windings typically require support members to hold the windings in a desired position and connection members to connect them to conductors carrying current from an inverter, which complicates the flow of the resin material around the winding ends. This causes changes in the orientation of the resin material, resulting in variations in the material strength of the resin material around the winding ends. Such variations in the material strength of the resin material apply stress to the support members, connection members, etc. at the winding ends, causing, for example, cracks and other damage, thereby limiting the service life of the rotating electric machine. To suppress the deterioration of reliability due to variations in the strength of the resin material around the winding ends, rotating electric machines with the following configuration have been disclosed.

[0004] That is, a conventional rotating electric machine includes a stator having a plurality of iron cores arranged in a circular ring shape, windings wound around each of the plurality of iron cores, connection terminals to which the windings are connected, and a molded member that partially covers the plurality of iron cores and the windings, and a rotor that rotates around a center that coincides with the center of the ring of the plurality of iron cores, and the molded member has a resin portion that covers the plurality of iron cores and the windings and a plurality of terminal exposure portions that expose the connection terminals (see, for example, Patent Document 1).

[0005] International Publication No. WO2022 / 244185

[0006] The above-described conventional rotating electric machine stator has a structure that improves reliability by providing a terminal exposure portion that exposes the connection portion at the end of the winding without insert molding. However, with this structure, it is necessary to seal the periphery of the end with a molding die to prevent resin from flowing into the end of the winding during insert molding. This results in a problem of a complex mold configuration and an increased mold size, which complicates the production process and reduces productivity. The present disclosure discloses a technology for solving the above-described problem, and aims to provide a stator and rotating electric machine that can be manufactured with high productivity while ensuring reliability, a stator manufacturing apparatus that can manufacture a highly reliable stator with high productivity, and a stator manufacturing method that can manufacture a highly reliable stator with high productivity.

[0007] The stator of the present disclosure includes: an annular core having a plurality of teeth protruding radially inward; windings wound around the teeth and housed in slots formed between adjacent teeth; and a resin portion in which the windings are sealed with a resin material, wherein the resin portion includes: a first resin portion formed by filling a gap extending axially along the windings in the slots between both ends of the core with the resin material; and a second resin portion formed by sealing coil end portions of the windings on both axial sides of the stator with the resin material, wherein a connecting portion connected to an end of the winding is arranged on the other axial side of the core so as to be located within a set first range in a plane perpendicular to the axial direction from a cross section perpendicular to the axial direction of the first resin portion, and the second resin portion on the other axial side is oriented within the first range with the axial direction as its orientation direction. Also, the rotating electric machine of the present disclosure includes: a stator configured as described above; and a rotor arranged coaxially with the stator. The stator manufacturing apparatus of the present disclosure is a stator manufacturing apparatus configured as described above, comprising: a first mold having an annular first space that accommodates the coil end portion on one axial side of the stator; and a second mold having an annular second space that accommodates the coil end portion on the other axial side of the stator; the first mold having a set number of gate through-holes at set intervals in the circumferential direction for injecting resin into the first space; and where the number of slots is n, the set number is at least one of n, 1 / 2n, and 1 / 4n.Furthermore, the stator manufacturing method of the present disclosure is a stator manufacturing method using a stator manufacturing apparatus configured as described above, which includes: arranging the first mold so that the coil end portion on one axial side of the iron core is accommodated in the first space of the first mold; and arranging the second mold so that the coil end portion on the other axial side is accommodated in the second space of the second mold; and simultaneously injecting the resin material into the first space from the multiple gate through-holes, filling the first space with the resin material to seal the coil end portion on one axial side, while sending the resin material into the second space of the second mold through the gap to fill the second space, thereby orienting the resin material in the axial direction in the first range within the second mold.

[0008] The stator, stator manufacturing apparatus, and stator manufacturing method disclosed herein provide a highly reliable and productive stator, and the rotating electric machine disclosed herein suppresses vibrations and provides a highly reliable rotating electric machine.

[0009] 1 is a perspective view showing a schematic configuration of a stator according to embodiment 1. FIG. 2 is a cross-sectional view of the stator according to embodiment 1. FIG. 3 is a longitudinal cross-sectional view showing a schematic configuration of a rotary electric machine according to embodiment 1. FIG. 4 is a view showing an arrangement configuration of ends of windings of the rotary electric machine according to embodiment 1. FIG. 5 is a longitudinal cross-sectional view of a manufacturing apparatus for illustrating an arrangement step by the manufacturing apparatus for a stator according to embodiment 1. FIG. 6 is a longitudinal cross-sectional view of a manufacturing apparatus for illustrating a closing step by the manufacturing apparatus for a stator according to embodiment 1. FIG. 7 is a longitudinal cross-sectional view showing an injection step by the manufacturing apparatus for a stator 1 according to embodiment 1. FIG. 8 is a longitudinal cross-sectional view showing an injection step by the manufacturing apparatus for a stator according to embodiment 1. FIG. 9 is a longitudinal cross-sectional view showing an opening step by the manufacturing apparatus for a stator according to embodiment 1. FIG. 10 is a view showing a result of analysis of an orientation rate of a resin member according to embodiment 1. FIG. 11 is a view showing a result of analysis of an orientation rate of a resin member according to embodiment 1. FIG. 12 is a view showing a result of analysis of an orientation rate of a resin member according to embodiment 1. FIG. 13 is a perspective view showing another example configuration of a stator according to embodiment 1. FIG. 14 is a cross-sectional view showing another example configuration of a stator according to embodiment 1. Fig. 1 is a perspective view showing another example of the configuration of the stator according to embodiment 1. Fig. 2 is a cross-sectional view showing another example of the configuration of the stator according to embodiment 1. Fig. 3 is a diagram showing the results of analyzing the orientation rate of a resin member according to a comparative example. Fig. 4 is a diagram showing the results of analyzing the orientation rate of a resin member according to a comparative example. Fig. 5 is a diagram showing the results of analyzing the orientation rate of a resin member according to a comparative example. Fig. 6 is a diagram showing another example of the arrangement configuration of the ends of the winding according to embodiment 1.

[0010] Embodiment 1. Figure 1 is a perspective view showing a schematic configuration of a stator 50 according to embodiment 1. Figure 2 is a cross-sectional view of the stator 50 shown in Figure 1 taken along line A-A. Figure 3 is a longitudinal cross-sectional view showing a schematic configuration of a rotating electric machine 100 according to embodiment 1. In the figure, the directions of the cylindrical stator 50 are indicated as a circumferential direction C, a radial direction X, and an axial direction Z. One side in the axial direction Z is indicated as one axial side Z1, and the other side is indicated as the other axial side Z2.

[0011] First, the configuration of the rotating electric machine 100 of this embodiment will be described with reference to Fig. 3. As shown in Fig. 3, the rotating electric machine 100 of this embodiment includes a stator 50 press-fitted onto the inner peripheral surface of the frame 3 by press fitting, shrink fitting, or the like, and a rotor 10 disposed inside the stator 50 in the radial direction X.

[0012] The rotor 10 is press-fitted and fixed onto the shaft 1. The shaft 1 is rotatably supported at both ends in the axial direction Z by bearings 2A and 2B fitted into a frame 3. A plurality of magnets (not shown) are provided at set intervals in the circumferential direction C on the outer peripheral surface of the rotor 10 in the radial direction X. A cover (not shown) is also provided to prevent these magnets from flying away.

[0013] Stator 50 includes an annular iron core 20, a winding 30 wound around iron core 20, and a resin portion 40 that seals winding 30. The detailed configuration of stator 50, which is a main part of this embodiment, will be further described below with reference to Figures 1 and 2.

[0014] As shown in Fig. 2, the core 20 is formed by connecting a plurality of segmented cores 20D in an annular shape. Each segmented core 20D has a yoke portion 20Y extending in the circumferential direction and teeth 20T protruding inward in the radial direction X from the yoke portion 20Y. Note that the winding 30 is not shown in Fig. 2. The winding 30 is wound around the teeth 20T in a concentrated winding manner, and is housed in slots 20S formed between adjacent teeth 20T. Also, as shown in Fig. 2, a resin insulating member 25S is attached to the core 20 as a first insulating portion that electrically insulates the core 20 from the winding 30.

[0015] An end of the winding 30 wound around the iron core 20 is disposed on the other axial side Z2 of the iron core 20. As shown in Fig. 3, the end of the winding 30 is provided with a crossover wire 30A as a connection portion and a connection terminal 35A as a connection portion connected to the crossover wire 30A. Three-phase terminals 35 for U, V, and W phases as conductive paths each having a plurality of connection terminals 35A are provided so as to protrude in the axial direction Z. A substantially annular resin insulating member 25B (second insulating portion) is provided as a connection portion and a support portion for holding each connection terminal 35A and the terminal 35.

[0016] The resin part 40 has a first resin part 40A formed to extend in the axial direction Z within the slot 20S as shown in Figure 2, and a second resin part 40B1 that seals the coil end part 30E formed on one axial side Z1 of the iron core 20, and a second resin part 40B2 that seals the coil end part 30E formed on the other axial side Z2 of the iron core 20 as shown in Figures 1 and 3.

[0017] The first resin portion 40A is formed by filling a resin material into a gap V that is formed between both ends of the core 20 in the axial direction Z and extends in the axial direction Z when the winding 30 is wound in concentrated winding. Thus, in this embodiment, as shown in FIG. 2 , the first resin portion 40A is formed in the center of the slot 20S in the circumferential direction C. However, the position of the first resin portion 40A is not limited to the center of the slot 20S in the circumferential direction C, and may be located anywhere within the slot 20S. Furthermore, as long as gaps V are formed between the windings 30, the winding method of the winding 30 is not limited to concentrated winding.

[0018] 1, the second resin portion 40B1 is formed with a plurality of recesses H recessed in the axial direction Z and provided at set intervals in the circumferential direction C. In this example, the number of recesses H formed is equal to the number of slots 20S. When the position of each recess H formed in the second resin portion 40B1 is projected onto the cross-sectional view shown in FIG. 2, the position of each recess H in the circumferential direction C corresponds to the center position of each slot 20S in the circumferential direction C.

[0019] Next, a description will be given of the arrangement of the ends of the windings 30 disposed on the other axial side Z2 of the iron core 20. Fig. 4 is a diagram showing the arrangement of the ends of the windings 30 on the other axial side Z2 of the rotating electric machine 100 according to embodiment 1. To simplify the drawing, portions of the windings 30 other than the ends of the windings 30 are not shown.

[0020] The jumper wire 30A provided at the end of the winding 30 and the connection terminal 35A connected to this jumper wire 30A are disposed within a set first range on the iron core 20. This first range is a range within a plane perpendicular to the axial direction Z, and more specifically, a range centered on a cross section of the first resin part 40A perpendicular to the axial direction Z, which is sandwiched between a first wire L1 and a second wire L2 that form a central angle of 50 degrees and extend radially from the center point O of the stator 50.

[0021] 3, the three-phase terminals 35 connected to the ends of the windings 30 are disposed with their tips exposed from the second resin portion 40B2 so as to protrude toward the control board 4 provided on the other axial side Z2. The tips of the terminals 35 are connected to the control board 4 by soldering.

[0022] An inverter circuit and a control circuit (not shown) are mounted on the control board 4, and these circuits are connected to terminals 35. Terminals of a connector 6 for power supply and signals are also connected to the control board 4. In this way, the control board 4 converts the power supplied via the connector 6 using the inverter, and supplies three-phase current to the windings 30 via the terminals 35. A cover 5 that covers the inverter and control circuit is provided on the other axial side Z2 of the control board 4.

[0023] Next, a manufacturing apparatus 1000 that molds the first resin portion 40A and the second resin portions 40B1, 40B2 by insert molding using a resin member, and a manufacturing method using this manufacturing apparatus 1000 will be described. FIG. 5 is a vertical cross-sectional view of the manufacturing apparatus 1000 for explaining the arrangement step performed by the manufacturing apparatus 1000 of the stator 50 according to the first embodiment. FIG. 6 is a vertical cross-sectional view of the manufacturing apparatus 1000 for explaining the closing step performed by the manufacturing apparatus 1000 of the stator 50 according to the first embodiment. FIG. 7 is a vertical cross-sectional view for explaining the injection step performed by the manufacturing apparatus 1000 of the stator 50 according to the first embodiment. FIG. 8 is a vertical cross-sectional view for explaining the injection step performed by the manufacturing apparatus 1000 of the stator 50 according to the first embodiment. FIG. 9 is a vertical cross-sectional view for explaining the opening step performed by the manufacturing apparatus 1000 of the stator 50 according to the first embodiment. Note that the axial direction Z is reversed from that of the stator 50 shown in FIG. 3 .

[0024] The manufacturing apparatus 1000 includes a first annular mold 61 having a first space 61C having an approximately annular shape for accommodating the coil end portion 30E on one axial side Z1 of the stator 50, and a second mold 62 having a second space 62C having an approximately annular shape for accommodating the coil end portion 30E on the other axial side Z2 of the stator 50.

[0025] The first mold 61 has a set number of gate through holes 61G for injecting resin into the first space 61C at set intervals in the circumferential direction C. In this example, the number of gate through holes 61G formed is equal to the number of slots 20S. Furthermore, the position in the circumferential direction C of each gate through hole 61G of the first mold 61 is provided at a location corresponding to the center position in the circumferential direction C of each slot 20S.

[0026] As shown in Fig. 5, in the arrangement step, the first space 61C and the second space 62C are arranged to face each other, and the stator 50 is arranged therebetween. Then, as shown in Fig. 6, in the closing step, the first mold 61 and the second mold 62 are closed to enclose the stator 50.

[0027] Next, as shown in Fig. 7 , in the injection process, first, the resin member R is poured through an injection hole 61I provided in the first mold 61. Then, as shown in Fig. 8 , the resin member R flows into the first space 61C through each gate through-hole 61G and flows within the substantially annular first space 61C. The flowing resin member R flows into the gap V extending in the axial direction Z, which is formed between the windings 30 in the slot 20C, while sealing the coil end portion 30E. Then, the resin member R passing through the gap V flows into the second space 62C in the second mold 62.

[0028] In this embodiment, since the stator 50 has twelve slots 20S, the resin member R flows from the first space 61C on one axial side Z1 through the twelve gaps V that are spaced at set intervals in the circumferential direction C to the second space 62C on the other axial side Z2, and then flows within the second space 62C to seal the coil end portion 30E on the other axial side Z2. Then, as shown in Figure 9, in the opening step, after the resin member R has solidified, the first mold 61 and the second mold 62 are opened, and the stator 50 with the molded resin portion 40 is removed.

[0029] In this way, the stator 50 is manufactured, having the first resin portion 40A extending in the axial direction Z and sealing the windings 30 in the slots 20S, and the second resin portions 40B1, 40B2 that respectively seal the windings 30 on both sides in the axial direction Z. The locations where the resin member R was inserted through the gate through-holes 61G leave traces on the stator 50 as recesses H as shown in FIG.

[0030] Furthermore, since the inner and outer surfaces of the iron core 20 are sealed with a mold, no resin will flow into the gap V from the inner or outer surfaces of the iron core 20, thereby ensuring a constant flow direction of the resin material R flowing into the second space 62C.

[0031] The orientation rate of the resin member R in the vicinity of the end of the winding 30 of the stator 50 formed in this manner will be described using the results of a flow analysis performed to analyze the orientation state of the glass filler. FIG. 10 is a diagram showing the results of an analysis of the orientation rate of the resin member R in the axial direction Z at each location of the stator 50 when the resin member R flows through the gap V in the stator 50 of this embodiment. FIG. 11 is a diagram showing the results of an analysis of the orientation rate of the resin member R in the axial direction Z at each location of the stator 50 when the resin member R flows into the second space 62C in the stator 50 of this embodiment. FIG. 12 is a diagram showing the results of an analysis of the orientation rate of the resin member R in the axial direction Z at each location of the stator 50 when the resin member R fills the second space 62C and solidifies in the stator 50 of this embodiment. FIG. 13 is a cross-sectional view showing the results of an analysis of the orientation rate in the axial direction Z near the end of the winding 30 of the stator 50 shown in FIG. 2. The numerical values ​​of the orientation rate in each figure indicate that the orientation rate in the direction perpendicular to the axial direction Z is low and the orientation rate in the direction along the axial direction Z is high.

[0032] 10 to 12, the resin member R flowing through the gap V toward the other axial side Z2 has an orientation rate along the axial direction Z that increases toward the other axial side Z2 within the gap V. Furthermore, as shown in Fig. 13, within the second space 62C, the orientation rates near the ends of the winding 30 are configured to be high, at orientation rates OR1 and OR2, and it can be seen that the orientation direction of the resin member R near the ends of the winding 30 is aligned in the Z-axis direction.

[0033] The reason why the orientation rate is configured in this manner in the stator 50 of this embodiment and the composition of the resin member R that is suitable for obtaining such an orientation rate configuration will be specifically explained using the characteristics of the resin member R.

[0034] When a resin composition containing a reinforcing material such as glass filler or glass beads is used for the thermoplastic resin (PA66 (polyamide), PBT (polybutylene terephthalate), PPS (polyphenylene sulfide), etc.) used as the resin component R in insert molding, the material strength such as the elastic modulus and linear expansion coefficient changes depending on the compounding ratio and orientation of the reinforcing material.

[0035] For example, reinforcing materials tend to be oriented in the flow direction (MD: Machine Direction), and the material strength in the flow direction is such that the elastic modulus is high and the linear expansion coefficient is low, whereas the material strength in the transverse direction (TD: Transverse Direction) is such that the elastic modulus is low and the linear expansion coefficient is high. It is also known that increasing the blending ratio of the reinforcing material increases the elastic modulus and decreases the linear expansion coefficient, whereas decreasing the blending ratio decreases the elastic modulus and increases the linear expansion coefficient. In this embodiment, in order to suppress deformation of the stator 50 of the rotating electric machine 100, it is necessary to select a resin member with high material strength, and a resin member containing a glass filler is suitable.

[0036] Next, when the stator 50 is manufactured by insert molding, the ends of the windings 30 are provided with connection parts, such as a substantially annular resin insulating member, jumper wires from the windings, and connection terminals, and the configurations and shapes of these connection parts are complex, which causes complex resin flow near the ends of the windings 30. Furthermore, there are multiple connection parts at the ends of the windings in the circumferential direction of the stator, and the resin flow varies at each connection part, which causes variations in the material strength of the resin material around each connection part.

[0037] Typically, copper is used for connection terminals and windings, but the material strength of thermoplastic resins used in insert molding is lower. Differences in linear expansion coefficients result in different amounts of deformation between the insert-molded resin material, the jumper wires from the windings, and the connection terminals. For example, at high temperatures, compared to the 23°C temperature at which the connection terminals are assembled, the resin material deforms more, resulting in tensile stress in the jumper wires at the connection terminals. Conversely, at low temperatures, the resin material deforms less, resulting in compressive stress in the jumper wires at the connection terminals. If the stress amplitude exceeds the fatigue strength of the jumper wires at the connection terminals, cracks will form. Particularly in the case of automotive parts, the wide temperature range between -40°C and 120°C limits the service life of these components.

[0038] As described above, the resin member R used in this embodiment is suitable for use in a thermoplastic resin that contains a reinforcing material to increase its material strength. However, due to the influence of the glass filler content and orientation, increasing the glass filler content increases the material strength but reduces its flowability. Furthermore, the orientation of the glass filler increases the material strength in the flow direction and decreases the material strength in the perpendicular direction. For reference, Table 1 shows the material strength data for winding wire (copper material), PA66, and PA66 + glass filler at 30% and 50%.

[0039]

[0040] As shown in Table 1, the linear expansion coefficient of the resin member is similar to that of copper in the flow direction, but is more than twice that of copper in the direction perpendicular to the flow direction. This trend is also seen in thermoplastic resins other than PA66. Therefore, it is desirable to adjust the glass filler content to account for the reduction in material strength due to variations in glass filler orientation. However, since it is difficult to confirm the orientation of the glass filler during insert molding, we performed resin flow analysis using the finite element method to estimate the material strength (elastic modulus, linear expansion coefficient, etc.) from the glass filler orientation and content. As a result, we confirmed that a glass filler content of 30% to 50% is optimal for PA66.

[0041] During insert molding, the resin material is injected into the first space 61C through the gate through-hole 61G at a set molding pressure above its melting temperature. If the resin insulating member 25A disposed between the iron core 20 and the winding 30 and the substantially annular resin insulating member 25B holding the three-phase terminals 35 and the connecting terminals 35A are components molded from thermoplastic resin, the injected resin material may soften due to the resin temperature and deform due to the molding pressure. The connecting terminals 35A held by the insulating member 25B may also deform. Furthermore, the jumper wire 30A from the winding 30 may bend due to the molding pressure. Therefore, it is appropriate to use a resin material for the insert molding that has a melting temperature equal to or lower than that of the insulating members 25A and 25B.

[0042] For reference, the melting temperatures of thermoplastic resins are PA66: 260°C, PBT: 225°C, and PPS: 280°C. For example, if PA66 (containing glass filler) is used for the insulating members 25A and 31, and PPS is used as the resin material for insert molding, the insulating member may soften and melt locally during insert molding, causing misalignment or deflection of the jumper wire 30A from the winding 30 and the connecting terminals 35A, and resulting in variations in the resin flow around the multiple connecting terminals 35A. For this reason, it is desirable to use PA66 or PBT as the resin material for insert molding.

[0043] The above are the composition and characteristics of the resin member R suitable for the stator 50 of this embodiment, but the present invention is not limited to these, and the resin member R may have other compositions and characteristics. Below, the reason why the orientation rate at the end of the winding 30 is configured as described above will be explained using the configuration of the stator 50 of this embodiment.

[0044] In the stator 50 of this embodiment, the resin member R flows along the axial direction Z within the gap V formed to extend in the axial direction Z. Therefore, as shown in Figures 11 and 12, the resin member R becomes more oriented in the axial direction Z, which is the flow direction, in response to this flow, and the orientation direction becomes uniform. The resin member R, whose orientation direction is thus uniform along the axial direction Z, flows into the second space 62C from the opening on the other axial side Z2 of the gap V.

[0045] As described above, the crossover wires 30A and connection terminals 35A serving as connection parts connected to the ends of the windings 30 are disposed within a set first range from the opening of the gap V through which the resin member R, whose orientation is aligned in the axial direction Z, is fed. This first range is a range within the second space 62C in which the orientation and flow direction of the resin member R are maintained along the axial direction Z, and is a range derived through experiments, simulations, etc. Therefore, as shown in the analysis results in Figure 13, in the stator 50 of this embodiment, the orientation direction of the resin member R is aligned in the Z-axis direction in the vicinity of the connection parts connected to the ends of the windings 30.

[0046] This reduces the difference in the linear expansion coefficient of the resin around the connection points of the windings 30 and reduces variations in resin flow near all connection points of the windings 30, thereby suppressing the occurrence of cracks and the like caused by compressive stress and tensile stress, thereby improving the reliability of the stator 50.

[0047] Furthermore, in this embodiment, the position of each gate through hole 61G is provided at the center position of each slot 20S in the circumferential direction C, i.e., on one axial side Z1 of the opening of the gap V. This allows the resin material R to flow into each gap V at the same time, and therefore allows the resin material R to flow into the second mold 62 on the other axial side Z2 from all gaps V at the same time. This makes it possible to more reliably align the orientation direction in the axial direction Z in the vicinity of the connection portion connected to the end of the winding 30.

[0048] Furthermore, since the first space 61C has a substantially annular shape, it is possible to further reduce variations in the timing at which the resin member R flows into all of the gaps V. Furthermore, since the second space 62C has a substantially annular shape, it is possible to realize a configuration in which the resin flows from the gaps V into the second mold 62 in the axial direction Z along the crossover wire 30A.

[0049] Generally, insert molding has good productivity and can reduce molding costs. Furthermore, by press-fitting or shrink-fitting the stator 50 into the frame 3 after resin molding, the amount of resin used during insert molding of the stator 50 can be reduced, thereby reducing costs.

[0050] Below, we will explain the configuration of a stator that is different from the above. Fig. 14 is a perspective view showing a schematic configuration of a stator 50A according to embodiment 1. Fig. 15 is a cross-sectional view of the stator 50A shown in Fig. 15 taken along line A-A. In the stator 50A, the number of gate through holes 61G in the first mold 61 is 1 / 4n of the number n of slots 20S in the iron core 20. In this configuration, the number n of slots 20S is 12, so the number of gate through holes 61G is three.

[0051] In this stator 50A, resin must flow evenly from one gate through-hole 61G into the four adjacent voids V. Therefore, this shape is applicable when there is a relatively large resin flow path, such as when a sufficient flow path in the circumferential direction C is secured at the end face on one axial side Z1 of the core 20 and the cross section of the voids V is large. Reducing the number of gate through-holes 61G in this way reduces the amount of material used for the resin member R flow path (runner) on the molding equipment. While recycling can reduce material costs for the flow path (runner), if the amount exceeds the resin supply capacity of the equipment, the equipment must be enlarged. Therefore, this configuration enables the equipment to be downsized and the amount of resin used in insert molding to be reduced.

[0052] Fig. 16 is a perspective view showing a schematic configuration of a stator 50B according to embodiment 1. Fig. 17 is a cross-sectional view of the stator 50B shown in Fig. 16 taken along line A-A. The stator 50A has a configuration in which the number of gate through holes 61G in the first mold 61 is 1 / 2n, where n is the number of slots 20S in the iron core 20. In this configuration, the number n of slots 20S is 12, so the number of gate through holes 61G is six.

[0053] In particular, when using a rotating electric machine 100 capable of high output, if the outer diameter of the iron core 20 is large and the space factor of the winding is configured to be high, the resin flow path may not be sufficiently secured and the cross section of the void V may also be small compared to the stator 50A. Therefore, by increasing the number of gate through holes 61G compared to the stator 50A, it is possible to reduce the variation in the timing of the resin material flowing into the void V. This makes it possible to downsize the equipment and reduce the amount of resin used in the insert molding, even for the stator 50B used in the rotating electric machine 100 capable of high output.

[0054] FIG. 18 is a perspective view showing a schematic configuration of a stator 50C according to embodiment 1. FIG. 19 is a cross-sectional view of the stator 50C shown in FIG. 18 taken along line A-A. In the examples described so far, the gate through holes 61G were arranged to correspond to the positions of the voids V. In this stator 50C, the number n of gate through holes 61G is configured to be less than the number of slots 20S to achieve equipment miniaturization and reduce the amount of resin material used. Furthermore, a configuration is provided that suppresses variations in the distance from each gate through hole 61G to each void V in order to suppress deviations in the timing at which the resin material R flows from each gate through hole 61G into each void V.

[0055] In the stators 50A and 50B described above, the gate through holes 61G were positioned on one axial side Z1 of the position where the voids V were present. In the present stator 50C, the number of gate through holes 61G is set to 1 / 2n, and the gate through holes 61G are positioned near the center of the tooth portions 20T in the circumferential direction C. When the position of each recess H formed in the second resin portion 40B1 is projected onto the cross-sectional view of the stator 50C shown in FIG. 19 , the position of each recess H in the circumferential direction C is indicated by H'. This makes the distances between all of the gate through holes 61G and the voids V constant, and therefore the timing of the resin material R flowing into all of the voids V can be synchronized.

[0056] Although the stator shape exemplified in this embodiment has a 12-slot configuration, it is not limited to 12 slots and can also be applied to stators with slots other than 12.

[0057] The following shows the results of analyzing the orientation state of a comparative example stator in which the positions and number of gate through-holes 61G as described above are not ensured. Fig. 20 is a diagram showing the results of analyzing the orientation rate of the resin member R in the axial direction Z at each location of the stator when the resin member R flows through the gap V in the comparative example stator. Fig. 21 is a diagram showing the results of analyzing the orientation rate of the resin member R in the axial direction Z at each location of the stator when the resin member R flows into the second space 62C in the comparative example stator. Fig. 22 is a diagram showing the results of analyzing the orientation rate of the resin member R in the axial direction Z at each location of the stator when the resin member R fills the second space 62C and solidifies in the comparative example stator. Fig. 23 is a cross-sectional view showing the results of analyzing the orientation rate of the resin member R in the axial direction Z near the end of the winding 30 in the comparative example stator.

[0058] As shown in Figure 23, it can be seen that in the second space 62C, the orientation rates near the ends of the winding 30 are orientation rates OR3 and OR4, which are lower than the orientation rate of the stator 50 of the above-mentioned embodiment.

[0059] 24 is a diagram showing another example of the arrangement of the ends of the windings according to embodiment 1. As shown in FIG. 24, for example, a crossover wire 30A serving as a wire connection may be arranged on one axial side Z1 by a length He from the end of the other axial side Z2 of the coil end portion 30E. In this way, the resin material R, whose orientation is aligned along the axial direction Z in the gap V, seals the wire connection while further flowing in the axial direction Z, so that the orientation near the wire connection can be aligned.

[0060] In the stator manufacturing method shown in Figures 5 to 9, an example is shown in which the resin member R is injected from above in the vertical direction with the one axial side Z1 positioned vertically upward and the other axial side Z2 positioned vertically downward. However, the orientation of the stator during manufacturing is not limited to this. For example, the other axial side Z2 may be positioned vertically upward and the one axial side Z1 positioned vertically downward, so that the resin member R flows from below to above in the vertical direction. Alternatively, the axial direction of the stator may be horizontal, and the resin member R may flow horizontally. The above-mentioned effect can be achieved as long as the resin member R is delivered into the second space 62C through the gap V.

[0061] Furthermore, the number of gate through-holes is exemplified as n, 1 / 2n, and 1 / 4n, where n is the number of slots, but the number of gate through-holes may be other numbers depending on the results of simulations, etc.

[0062] Furthermore, although insulating member 25B, jumper wire 30A, and connection terminal 35A are shown as the connecting parts connected to the ends of the windings, the present invention is not limited to these components. Any component that is connected to the ends of the windings and to which stress due to the orientation direction of the resin member can be applied can achieve the effects of the present invention.

[0063] The stator of this embodiment configured as described above includes: an annular core having a plurality of teeth protruding radially inward, windings wound around the teeth and housed in slots formed between adjacent teeth, and a resin portion in which the windings are sealed with a resin material, wherein the resin portion includes: a first resin portion formed by filling gaps extending axially along the windings in the slots between both ends of the core with the resin material; and a second resin portion formed by sealing coil end portions of the windings on both axial sides of the stator with the resin material, wherein a connecting portion connected to an end of the winding is arranged on the other axial side of the core so as to be located within a set first range in a plane perpendicular to the axial direction from a cross section perpendicular to the axial direction of the first resin portion, and the second resin portion on the other axial side is oriented within the first range with the axial direction as its orientation direction. Also, the rotating electric machine of this embodiment configured as described above includes the stator configured as described above and a rotor arranged coaxially with the stator.

[0064] This aligns the orientation of the windings around their ends, resulting in a stator that is highly reliable, highly productive, and has ensured rigidity. This also helps to suppress vibrations in the rotating electric machine. Furthermore, because the winding ends are not exposed, there is no need to strictly control the positional accuracy of the winding connections, which helps reduce costs.

[0065] Furthermore, in the stator of this embodiment configured as described above, the first range is a range between a first line and a second line that extend radially from the center point of the stator, centered on a cross section perpendicular to the axial direction of the first resin portion, and that form a central angle of 50 degrees.

[0066] In this way, by determining a first range in which the desired orientation direction is ensured, centered on a cross section perpendicular to the axial direction of the first resin part, i.e., the gap portion through which the resin material is fed, and arranging the end of the winding within that range, it is possible to more reliably align the orientation direction around the end of the winding.

[0067] Furthermore, the manufacturing apparatus for the stator of this embodiment configured as described above comprises a first mold having an annular first space for accommodating the coil end portions on one axial side of the stator, and a second mold having an annular second space for accommodating the coil end portions on the other axial side of the stator, wherein the first mold has a set number of gate through holes at set intervals in the circumferential direction for injecting resin into the first space, and wherein, where n is the number of slots, the set number is at least one of n, 1 / 2n, and 1 / 4n. Furthermore, the manufacturing method for the stator of this embodiment configured as described above comprises: arranging the first mold so that the coil end portions on one axial side of the iron core are accommodated in the first space of the first mold, and arranging the second mold so that the coil end portions on the other axial side are accommodated in the second space of the second mold, The resin material is simultaneously injected into the first space from each of the multiple gate through-holes, filling the first space with the resin material to seal the coil end portion on one axial side, and then the resin material is sent through the gap portion into the second space of the second mold to fill the second space, thereby orienting the resin material in the axial direction in the first range within the second mold.

[0068] In this way, the orientation direction of the windings around the ends is uniform, and a stator with high reliability, high productivity, and ensured rigidity can be manufactured.

[0069] Although exemplary embodiments are described in the present disclosure, the various features, aspects, and functions described in the embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are anticipated within the scope of the technology disclosed in this specification. For example, variations in, addition to, or omission of at least one component are included.

[0070] 20T Teeth portion, 20 Iron core, 20S Slot, 25B Insulating member (connecting portion, second insulating portion, support portion), 30 Winding, 30A Jumper wire (connecting portion), 30E Coil end portion, 35A Connecting terminal (connecting portion), 40 Resin portion, 40A First resin portion, 40B1 Second resin portion, 40B2 Second resin portion, 50, 50A, 50B, 50C Stator, 61 First mold, 61C First space, 62 Second mold, 62C Second space, 61G Gate through hole, 100 Rotating electric machine, 1000 Stator manufacturing apparatus, R Resin member, V Air gap portion.

Claims

1. A stator comprising: an annular core having a plurality of teeth protruding radially inward; windings wound around the teeth and housed in slots formed between adjacent teeth; and a resin portion in which the windings are sealed with a resin material, wherein the resin portion comprises: a first resin portion formed by filling the resin material into voids extending in the axial direction along the windings in the slots between both ends of the core with the resin material; and a second resin portion formed by sealing coil end portions of the windings on both axial sides of the stator with the resin material, wherein a connecting portion connected to an end of the winding is arranged on the other axial side of the core so as to be located within a set first range in a plane perpendicular to the axial direction from a cross section perpendicular to the axial direction of the first resin portion, and the second resin portion on the other axial side is oriented within the first range, with the axial direction as its orientation direction.

2. A stator as described in claim 1, wherein the first range is a range between a first line and a second line that extend radially from the center point of the stator, centered on a cross section perpendicular to the axial direction of the first resin portion, and that form a central angle of 50 degrees.

3. A stator according to claim 1 or claim 2, wherein the wire connection portion is disposed on one axial side of the other axial end of the coil end portion.

4. A stator as described in any one of claims 1 to 3, wherein the first resin portion is formed so that the orientation rate in the axial direction on the other axial side is higher than the orientation rate in the axial direction on one axial side.

5. A stator according to any one of claims 1 to 4, wherein the connection portion is at least one of a connection terminal that connects the end of the winding with a conductive path that supplies current to the winding, or a support portion that supports the end of the winding.

6. A stator as claimed in any one of claims 1 to 5, comprising: a first insulating part made of resin that insulates the winding from the iron core; and a second insulating part made of resin that supports the end of the winding as the connecting part, wherein the resin member is a thermoplastic resin composition that contains 30% to 50% glass filler and has a melting point lower than that of the first insulating part and the second insulating part.

7. A rotating electric machine comprising the stator according to any one of claims 1 to 6 and a rotor disposed coaxially with the stator.

8. A stator manufacturing apparatus as set forth in any one of claims 1 to 6, comprising: a first mold having an annular first space for accommodating the coil end portion on one axial side of the stator; and a second mold having an annular second space for accommodating the coil end portion on the other axial side of the stator, wherein the first mold has a set number of gate through-holes at set intervals in the circumferential direction for injecting resin into the first space, and wherein, when the number of slots is n, the set number is at least one of n, 1 / 2n, and 1 / 4n.

9. The stator manufacturing apparatus according to claim 8, wherein the gate through-hole is disposed at a position on one axial side of the slot in the first mold.

10. The stator manufacturing apparatus according to claim 9, wherein the gate through-hole is disposed in the first mold at a position on one axial side of the opening of the void portion.

11. A stator manufacturing apparatus as described in claim 8, wherein, in a configuration in which the number of gate through holes is 1 / 2n, the gate through holes are arranged in the first mold at a position on one axial side of the radial center of the tooth portion.

12. A method for manufacturing a stator using the stator manufacturing apparatus described in any one of claims 8 to 11, comprising: arranging the first mold so that the coil end portion on one axial side of the iron core is accommodated within the first space of the first mold; and arranging the second mold so that the coil end portion on the other axial side is accommodated within the second space of the second mold; and simultaneously injecting the resin material into the first space from the multiple gate through-holes, filling the first space with the resin material to seal the coil end portion on one axial side, while sending the resin material through the gap into the second space of the second mold to fill the second space, thereby orienting the resin material in the axial direction in the first range within the second mold.

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