Method for manufacturing rotor , rotor, rotating electrical machine, and automobile

Abstract

This method for manufacturing a rotor 20 comprising a rotor core 23, a permanent magnet 25 disposed within a space S of the rotor core 23, and an element unit 50 that transmits temperature information regarding the temperature of the permanent magnet 25 includes an attachment step for attaching the element unit 50 to the rotor core 2, the element unit 50 having a temperature-sensitive element 51 whose electrical resistance changes according to the temperature of the permanent magnet 25 and a coil 52 electrically connected to the temperature-sensitive element 51. In the attachment step, the temperature-sensitive element 51 is attached so as to be in contact with a side surface 25A of the permanent magnet 25 in the space S of the rotor core 23.

Description

Method for manufacturing a rotor, rotor, rotating electrical machine, and motor vehicle 【0001】 The present disclosure relates to a method for manufacturing a rotor, a rotor, a rotating electrical machine, and a motor vehicle. 【0002】 A magnet temperature information output device is provided for a rotating electrical machine including a stator and a rotor in which permanent magnets are arranged, and outputs temperature information regarding the temperature of the permanent magnets (see, for example, Patent Document 1). This magnet temperature information output device includes a temperature sensing element, a first coil, a second coil, and an output unit. The temperature sensing element is provided on the rotor and its electrical resistance changes according to the temperature of the permanent magnet. The first coil is electrically connected to the temperature sensing element. The second coil is provided on the stator and magnetically coupled to the first coil. The output unit outputs an electrical signal corresponding to the magnitude of the current flowing through the second coil. 【0003】 Japanese Patent Application Laid-Open No. 2021-39019 【0004】 In a rotating electrical machine, the magnets may extend in the axial direction of the rotor. In magnets having this configuration, heat is likely to be dissipated at the end portions in the extending direction of the magnets, and it is difficult to dissipate heat at positions closer to the central portion in the extending direction of the magnets. Therefore, a technique for measuring the temperature of a predetermined portion such as the central portion in the extending direction of the magnet where it is difficult to dissipate heat is required. 【0005】 One aspect of the present disclosure aims to provide a method for manufacturing a rotor that can accurately acquire temperature information of a predetermined portion of a magnet. Another aspect of the present disclosure aims to provide a rotor that can accurately acquire temperature information of a predetermined portion of a magnet. Still another aspect of the present disclosure aims to provide a rotating electrical machine including the above-described rotor. Still another aspect of the present disclosure aims to provide a motor vehicle including the above-described rotating electrical machine. 【0006】A rotor manufacturing method according to one embodiment comprises a rotor core, magnets disposed within the gaps of the rotor core, and a temperature information transmitting device for transmitting temperature information relating to the temperature of the magnets, wherein the temperature information transmitting device comprises a temperature-sensing element whose electrical resistance changes according to temperature and a coil electrically connected to the temperature-sensing element, and the method includes an attachment step of attaching the temperature information transmitting device to the rotor core, in which the temperature-sensing element is attached so as to contact the side surface of the magnets within the gaps of the rotor core. 【0007】 In the rotor manufacturing method according to one of the above embodiments, the temperature-sensing element is mounted in the mounting step so as to contact the side surface of the magnet within the gap of the rotor core. As a result, the electrical resistance of the temperature-sensing element changes in accordance with the temperature at the side surface of the magnet (closer to the center of the magnet), which is less efficient at dissipating heat than the end surface. In this way, the temperature-sensing element can detect the temperature of the region of the magnet that is less efficient at dissipating heat. Therefore, temperature information of a predetermined part of the magnet can be obtained with high accuracy. 【0008】 In one of the above embodiments, during the mounting process, a resin member that has thermal expansion properties may be provided in the gap to position the temperature-sensing element so that it contacts the side surface of the magnet, and the thermal expansion of the resin member may cause the temperature-sensing element to come into contact with the side surface of the magnet. In this method, contact between the temperature-sensing element and the magnet is ensured, and the temperature of the magnet can be detected more accurately. 【0009】 In one of the above embodiments, during the mounting process, a metal member that is elastic is provided in the gap to position the temperature-sensing element so that it contacts the side surface of the magnet, and the elastic force of the metal member causes the temperature-sensing element to come into contact with the side surface of the magnet. In this method, contact between the temperature-sensing element and the magnet is ensured, and the temperature of the magnet is detected more accurately. 【0010】 In one of the above embodiments, the temperature sensing element and the coil may be electrically connected using circuit board wiring or wire wrapping. This method allows the temperature information transmitting device to be easily positioned so as to ensure the temperature detection accuracy of the magnet. 【0011】One embodiment described above may include a sealing step to obtain a temperature information transmitting device in which the coil is sealed with a sealing member. By sealing the coil with a sealing member in this way, a temperature information transmitting device can be manufactured that can suppress component detachment, wire breakage, and cooling oil intrusion. Furthermore, by sealing the coil with a sealing member, damage to components can be avoided when attaching the temperature information transmitting device to the rotor core. 【0012】 A rotor according to another embodiment comprises a rotor core, magnets disposed within the gaps of the rotor core, and a temperature information transmitting device that transmits temperature information relating to the temperature of the magnets, wherein the temperature information transmitting device has a temperature-sensing element whose electrical resistance changes according to temperature, and a coil electrically connected to the temperature-sensing element, and the temperature-sensing element is in contact with the side surface of the magnets within the gaps of the rotor core. 【0013】 In the rotor according to the other embodiment described above, the temperature-sensing element is in contact with the side surface of the magnet within the gap of the rotor core. As a result, the electrical resistance of the temperature-sensing element changes in response to temperature at the side surface of the magnet (closer to the center of the magnet), which is less efficient at dissipating heat than the end face. In this way, the temperature-sensing element can detect the temperature of the region of the magnet that is less efficient at dissipating heat. Therefore, the rotor can accurately acquire temperature information for a predetermined part of the magnet. 【0014】 In one of the other embodiments described above, a positioning member is provided for positioning the temperature-sensing element so that it contacts the side surface of the magnet, and the positioning member may press the temperature-sensing element toward the magnet. In this configuration, a rotor is provided in which the temperature of the magnet is detected more accurately by the temperature-sensing element. 【0015】 A rotating electric machine according to yet another embodiment comprises the rotor described above, a stator, and a temperature information receiving device attached to the stator that receives temperature information transmitted from a temperature information transmitting device. 【0016】 Another embodiment of the automobile includes the aforementioned rotating electric machine. 【0017】According to one aspect of this disclosure, a method for manufacturing a rotor is provided that can accurately acquire temperature information of a predetermined part of a magnet. According to another aspect of this disclosure, a rotor is provided that can accurately acquire temperature information of a predetermined part of a magnet. According to yet another aspect of this disclosure, a rotating electric machine equipped with the rotor described above is provided. According to yet another aspect of this disclosure, an automobile equipped with the rotating electric machine described above is provided. 【0018】 Figure 1 is a schematic diagram showing the configuration of a magnet temperature information output device and a rotating electric machine according to one embodiment. Figure 2 is a circuit diagram showing an example of a magnet temperature information output device. Figure 3 is an exploded perspective view of the element unit. Figure 4 is a perspective view showing the element unit attached to the rotor core of the rotor. Figure 5 is a perspective view showing an enlarged portion of Figure 4. Figure 6 is a diagram showing the gap in the rotor core. Figure 7 is a schematic diagram showing the contact configuration of the temperature sensing element. Figure 8 is a schematic diagram showing the contact configuration of the temperature sensing element. Figure 9 is a schematic diagram showing the configuration of an electric vehicle. 【0019】 Preferred embodiments of this disclosure will be described in detail below with reference to the attached drawings. In the description of the drawings, the same or equivalent elements will be denoted by the same reference numerals, and redundant descriptions will be omitted. 【0020】 Referring to Figure 1, the configuration of the magnet temperature information output device 1 and the rotating electric machine MT equipped with the magnet temperature information output device 1 according to this embodiment will be described. Figure 1 is a schematic diagram showing the configuration of the magnet temperature information output device and the rotating electric machine according to this embodiment. 【0021】 As shown in Figure 1, the magnet temperature information output device 1 is installed on the rotating electric machine MT. The rotating electric machine MT is, for example, a motor. The motor includes, for example, an IPM motor or an SPM motor. As shown in Figure 1, the rotating electric machine MT comprises a stator 10 and a rotor 20. The rotor 20 is located inside the stator 10. 【0022】The rotor 20 includes a shaft 21, a rotor core 23, and a plurality of permanent magnets 25. The shaft 21 has a cylindrical shape. The rotor core 23 has a cylindrical shape. The rotor core 23 has an axial hole into which the shaft 21 is fitted. The shaft 21 and the rotor core 23 rotate integrally around the central axis of the shaft 21. Each permanent magnet 25 is positioned on the rotor core 23 such that its extending direction is parallel to the central axis of the shaft 21. The statement "the extending direction of the permanent magnet 25 is parallel to the central axis of the shaft 21" does not necessarily mean that the extending direction of the permanent magnet 25 is parallel to the central axis of the shaft 21. Even if there are slight differences, manufacturing errors, or measurement errors within a predetermined range, the extending direction of the permanent magnet 25 may still be considered parallel to the central axis of the shaft 21. If there are slight differences within a predetermined range, for example, if the angle between the extending direction of the permanent magnet 25 and the central axis of the shaft 21 is within ±2 degrees, the extending direction of the permanent magnet 25 and the central axis of the shaft 21 may be considered parallel. The central axis of the shaft 21 is the rotation axis of the rotor 20. The direction in which the rotation axis of the rotor 20 extends is the rotation axis direction D of the rotor 20. One magnet may constitute one pole, or multiple magnets may constitute one pole. When one magnet constitutes one pole, the multiple permanent magnets 25 are arranged at equal angular intervals with respect to the rotation axis of the rotor 20. "Equal angular intervals" does not necessarily mean that each angular interval is the same. Even if there are slight differences, manufacturing errors, or measurement errors within a predetermined range, the angular intervals may be considered equal. If there are slight differences within a predetermined range, for example, if each angular interval with respect to the rotation axis of the rotor 20 of the permanent magnet 25 is within ±10% of the average angular interval of all angular intervals, then each angular interval with respect to the rotation axis of the rotor 20 of the permanent magnet 25 may be considered uniform. 【0023】If the rotating electric machine MT is an IPM motor, the multiple permanent magnets 25 are arranged inside the rotor core 23. If the rotating electric machine MT is an SPM motor, the multiple permanent magnets 25 are arranged on the surface of the rotor core 23. Each permanent magnet 25 includes a rare earth permanent magnet. Each permanent magnet 25 includes, for example, a neodymium sintered magnet. Each permanent magnet 25 may also include a sintered magnet other than a rare earth permanent magnet, or a magnet other than a sintered magnet. The magnet other than a sintered magnet includes, for example, a bonded magnet or a hot-worked magnet. 【0024】 The stator 10 includes a cylindrical stator core (not shown) arranged to surround the outer circumference of the rotor 20, and a plurality of stator coils 11. The stator 10 may further include a case that surrounds the stator core, the plurality of stator coils 11, and the rotor 20. A uniform width air gap is provided between the stator 10 and the rotor 20. "Uniform width" does not necessarily mean that the width of each air gap between the stator 10 and the rotor 20 is uniform. The width of each air gap between the stator 10 and the rotor 20 may be considered uniform even if there are slight differences, manufacturing errors, or measurement errors within a preset range. If there are slight differences within a preset range, for example, if the width of each air gap between the stator 10 and the rotor 20 is within ±10% of the average width of all air gaps, the width of each air gap between the stator 10 and the rotor 20 may be considered uniform. The stator core holds the plurality of stator coils 11. Each stator coil 11 is positioned on the inner circumference side of the stator core. The multiple stator coils 11 are arranged at equal angular intervals with respect to the rotation axis of the rotor 20. 【0025】The rotating electric machine MT is connected to a control circuit 41. The control circuit 41 is connected to a power supply 43. The control circuit 41 adjusts the drive current from the power supply 43 and supplies three-phase alternating current to each stator coil 11. The control circuit 41 controls the value of the three-phase alternating current supplied to each stator coil 11. The control circuit 41 includes, for example, an inverter circuit. As the three-phase alternating current is supplied to each stator coil 11, each stator coil 11 forms a rotating magnetic field that rotates the rotor 20. The power supply 43 includes, for example, an electrical energy storage device. The electrical energy storage device includes, for example, a secondary battery or a capacitor. 【0026】 Next, with reference to Figure 2, the configuration of the magnet temperature information output device 1 will be described in more detail. Figure 2 is a circuit diagram showing an example of a magnet temperature information output device. 【0027】 The magnet temperature information output device 1 outputs temperature information relating to the temperature of the permanent magnet 25. To realize this function, the magnet temperature information output device 1 includes an element unit (temperature information transmitting device) 50, an element unit (temperature information receiving device) 60, an electrical resistance element 70, and an output unit 80. In this embodiment, there is one element unit 50 and one element unit 60. The element unit 50 is provided on the rotor 20. The element unit 60 is provided on the stator 10. The element unit 60 is provided, for example, on the stator core. The element unit 50 and the element unit 60 are arranged to face each other in a direction parallel to the rotation axis of the rotor 20 when the rotor 20 is at a predetermined rotational angle position. "A direction parallel to the rotation axis of the rotor 20" does not necessarily mean only a direction parallel to the rotation axis of the rotor 20. Even if slight differences, manufacturing tolerances, or measurement errors within a predetermined range are included, the direction may be considered parallel to the rotation axis of the rotor 20. If slight differences within a predetermined range are included, for example, if the angle with the rotation axis of the rotor 20 is within ±2 degrees, the direction may be considered parallel to the rotation axis of the rotor 20. 【0028】As shown in Figure 2, the element unit 50 includes a temperature-sensing element 51 and a coil 52. The temperature-sensing element 51 and the coil 52 are provided on the rotor 20. The temperature-sensing element 51 is provided on at least one of the multiple permanent magnets 25. In this embodiment, the temperature-sensing element 51 is provided on only one permanent magnet 25. The temperature-sensing element 51 is positioned in contact with the permanent magnet 25. The temperature-sensing element 51 may be positioned in the vicinity of the permanent magnet 25. The electrical resistance of the temperature-sensing element 51 changes according to the temperature of the permanent magnet 25. The temperature-sensing element 51 may be, for example, a thermistor or a Hall element. The thermistor may be, for example, an NTC thermistor or a PTC thermistor. When the temperature-sensing element 51 is an NTC thermistor, the electrical resistance of the temperature-sensing element 51 decreases as the temperature rises. The coil 52 is electrically connected to the temperature-sensing element 51. In this embodiment, both ends of the coil 52 are electrically connected to both ends of the temperature sensing element 51. 【0029】The element unit 60 includes a coil 61 and a capacitor 63. The coil 61 is positioned on the stator 10 such that it faces the coil 52 in the direction of the rotation axis D of the rotor 20 when the rotor 20 is at a predetermined rotational angle. The coil 52 and the coil 61 are positioned so that they face each other in the direction of the rotation axis D of the rotor 20 when the rotor 20 is at a predetermined rotational angle. The coil 61 is magnetically coupled to the coil 52. When the rotor 20 is at a predetermined rotational angle, it is preferable that the coil axis of the coil 61 and the coil axis of the coil 52 coincide, but the misalignment between the coil axis of the coil 61 and the coil axis of the coil 52 is sufficient as long as it is within 15 degrees, or even within 10 degrees. If the misalignment between the coil axis of the coil 61 and the coil axis of the coil 52 is within the above range, the impact on detection accuracy is small. The coil 61 is electrically connected to an AC power supply PS. The AC power supply PS may be, for example, an inverter. An AC signal of a predetermined frequency is applied to the coil 61 from the AC power supply PS. An AC voltage is applied to the coil 61 from an AC power supply PS. The predetermined frequency is higher than the drive frequency of the rotating electric machine MT. The predetermined frequency is, for example, 10 to 2000 times the drive frequency of the rotating electric machine MT. The capacitor 63, together with the coil 61, constitutes an LC resonant circuit. The capacitor 63 may also constitute an LC resonant circuit together with the coil 52 and the coil 61. The capacitor 63 is inserted, for example, so as to be connected in parallel with the coil 61. For example, if the coil 52 constitutes the first coil, the coil 61 constitutes the second coil. 【0030】For example, the predetermined frequency may be less than or equal to a predetermined resonant frequency that excites the coil 52. That is, the frequency of the voltage applied to the coil 61 may be less than or equal to a predetermined resonant frequency that excites the coil 52. The predetermined resonant frequency is, for example, the resonant frequency of a circuit that is equivalent to the circuit in the magnetic temperature information output device 1 when the coil 52 and the coil 61 are magnetically coupled and the temperature of the temperature sensing element 51 is at a predetermined temperature. In this embodiment, the circuit includes the temperature sensing element 51, the coil 52, the coil 61, and the capacitor 63. The predetermined temperature is, for example, room temperature. Room temperature is, for example, 15°C to 30°C. In this embodiment, the predetermined temperature is 25°C. 【0031】 The electrical resistance element 70 is electrically connected to the element unit 60. The electrical resistance element 70 may also be electrically connected to the coil 61. In this embodiment, the electrical resistance element 70 is provided on the stator 10 and is inserted between the coil 61 and the AC power supply PS. 【0032】 The output unit 80 is electrically connected to the element unit 60 and the electrical resistance element 70. The output unit 80 may also be electrically connected to the coil 61. That is, the coil 61 may be electrically connected to the electrical resistance element 70 and the output unit 80. In this embodiment, the output unit 80 is provided on the stator 10. The output unit 80 outputs an electrical signal corresponding to the magnitude of the voltage drop occurring in the electrical resistance element 70. The output unit 80 may output an electrical signal indicating the magnitude of the voltage drop occurring in the electrical resistance element 70. The output unit 80 includes, for example, a voltmeter. The voltmeter may consist of, for example, an arithmetic unit including a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory). The arithmetic unit may be, for example, a microcomputer. In this case, the voltmeter loads a program stored in the ROM into the RAM and executes it with the CPU to output the electrical signal corresponding to the magnitude of the voltage drop occurring in the electrical resistance element 70 as described above. 【0033】 A magnetic flux corresponding to the AC voltage applied from the AC power source PS is generated in coil 61. As the rotor 20 rotates and coil 61 and coil 52 move closer together, the magnetic flux generated in coil 61 passes through coil 52. When the magnetic flux generated in coil 61 passes through coil 52, power is generated in coil 52 corresponding to the change in magnetic flux passing through coil 52. In other words, as the rotor 20 rotates and coil 61 and coil 52 move closer together, coil 61 and coil 52 become magnetically coupled. Alternatively, it can be said that coil 61 excites coil 52 and supplies power to coil 52. 【0034】 As the electrical resistance of the temperature-sensing element 51 changes in accordance with the temperature of the permanent magnet 25, the magnetic flux generated in the coil 61 changes in accordance with the change in the electrical resistance of the temperature-sensing element 51. As a result, the current flowing through the coil 61 changes. This change in the current flowing through the coil 61 changes the magnitude of the voltage drop that occurs in the electrical resistance element 70. 【0035】 As the temperature of the permanent magnet 25 rises and the electrical resistance of the temperature-sensing element 51 decreases, the magnetic flux generated in the coil 61 increases. As a result, the current flowing through the coil 61 increases, and the magnitude of the voltage drop across the electrical resistance element 70 also increases. As the temperature of the permanent magnet 25 decreases and the electrical resistance of the temperature-sensing element 51 increases, the magnetic flux generated in the coil 61 decreases. As a result, the current flowing through the coil 61 decreases, and the magnitude of the voltage drop across the electrical resistance element 70 also decreases. In other words, as the temperature of the permanent magnet 25 rises, the magnitude of the voltage drop across the electrical resistance element 70 increases. Similarly, as the temperature of the permanent magnet 25 falls, the magnitude of the voltage drop across the electrical resistance element 70 decreases. 【0036】The output unit 80 captures the magnetic flux generated in the coil 61 as the magnitude of the voltage drop occurring in the electrical resistance element 70. The magnitude of the voltage drop captured by the output unit 80 corresponds to the change in the electrical resistance of the temperature sensing element 51, that is, the change in the temperature of the permanent magnet 25. Therefore, the electrical signal output from the output unit 80 includes temperature information related to the temperature of the permanent magnet 25. In other words, the output unit 80 outputs an electrical signal corresponding to the magnitude of the voltage drop occurring in the electrical resistance element 70 as the above temperature information. As a result, temperature information related to the temperature of the permanent magnet 25 is transmitted wirelessly between the element unit 50 and the output unit 80 via the element unit 60. 【0037】 The electrical signal output from the output unit 80 is input to the control circuit 41 as temperature information. The control circuit 41 acquires an electrical signal corresponding to the magnitude of the voltage drop occurring in the electrical resistance element 70 output from the magnet temperature information output device 1. Based on the acquired electrical signal, the control circuit 41 obtains the temperature of the permanent magnet 25. In other words, in this embodiment, the control circuit 41 functions as a magnet temperature acquisition device. 【0038】 The control circuit 41 obtains the temperature of the permanent magnet 25, for example, as follows. First, the control circuit 41 refers to data showing the relationship between the electrical signal corresponding to the magnitude of the voltage drop occurring in the electrical resistance element 70 and the temperature. This data may be stored in the control circuit 41 or in an external server different from the control circuit 41. Next, the control circuit 41 obtains the temperature corresponding to the acquired electrical signal from the above data as the temperature of the permanent magnet 25. 【0039】 The control circuit 41 controls the driving state of the rotating electric machine MT based on the temperature of the permanent magnet 25 obtained. For example, the control circuit 41 controls the driving state of the rotating electric machine MT as follows: When the control circuit 41 determines that the temperature of the permanent magnet 25 obtained has risen to a predetermined first threshold, the control circuit 41 controls the power supply to limit the rotational speed of the rotating electric machine MT. When the control circuit 41 determines that the temperature of the permanent magnet 25 obtained has fallen to a predetermined second threshold that is lower than the first threshold, the control circuit 41 controls the power supply to release the restriction on the rotational speed of the rotating electric machine MT. 【0040】 The control circuit 41 may control the driving state of the rotating electric machine MT as follows. That is, the control circuit 41 may control, for example, the driving frequency input to the rotating electric machine MT based on the obtained temperature of the permanent magnet 25. When the control circuit 41 determines that the obtained temperature of the permanent magnet 25 has risen to a predetermined first threshold value, the control circuit 41 controls to lower the driving frequency so as to limit the rotation speed of the rotating electric machine MT. When the control circuit 41 determines that the obtained temperature of the permanent magnet 25 has dropped to a predetermined second threshold value smaller than the first threshold value, the control circuit 41 controls to increase the driving frequency so as to release the limitation on the rotation speed of the rotating electric machine MT. 【0041】 The control circuit 41 includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The control circuit 41 obtains the temperature of the permanent magnet 25 and controls the driving state of the rotating electric machine MT as described above by, for example, loading a program stored in the ROM into the RAM and executing it with the CPU. 【0042】 Next, referring to FIG. 3, the element unit 50 will be described. FIG. 3 is an exploded perspective view of the element unit 50. As shown in FIG. 3, the element unit 50 has a temperature sensing element 51, a coil 52, a housing (sealing member) 53, and a wiring 54. 【0043】 The coil 52 is mounted on a substrate 55. The coil 52 is mounted on the substrate 55 by soldering. 【0044】 The housing 53 is a member that seals the coil 52. The housing 53 integrates the coil 52 and the substrate 55. The housing 53 is formed of resin. In the present embodiment, the housing 53 is composed of a resin case 53A and a filling resin (not shown). Specifically, the housing 53 is formed by filling resin in a state where the coil 52 and the substrate 55 are housed in the resin case 53A. 【0045】Wiring 54 electrically connects the temperature sensing element 51 and the coil 52. For example, both ends of the temperature sensing element 51 are electrically connected to both ends of the coil 52 by the wiring 54 respectively. A capacitor may be connected to the coil 52 in parallel with the temperature sensing element 51. In the example shown in this embodiment, the temperature sensing element 51 and the coil 52 are electrically connected using a substrate wiring. The coil 52 is provided on the substrate 55, and both ends of the coil 52 are connected to the wiring 54 by the substrate wiring respectively. 【0046】 FIG. 4 is a perspective view showing a state where the element unit 50 is attached to the rotor core 23 of the rotor 20. FIG. 5 is a perspective view showing an enlarged part of FIG. 4. 【0047】 As shown in FIGS. 4 and 5, the element unit 50 is attached to the rotor 20. The element unit 50 is disposed on the end face 23A in the axial direction of the rotor core 23 of the rotor 20. The element unit 50 is fixed to the rotor 20 by the fixture 56. The fixture 56 attaches the element unit 50 to the rotor core 23 by pressing the housing 53 against the rotor core 23 side. 【0048】 The fixture 56 is formed of, for example, metal. The fixture 56 has a structure that engages with the housing 53. The fixture 56 is fixed to the rotor core 23 by screws or welding. 【0049】 The element unit 50 is attached to the rotor core 23 such that the temperature sensing element 51 abuts against the side surface 25A of the permanent magnet 25 inside the gap S of the rotor core 23. As shown in FIG. 6, the rotor core 23 has a gap S. The gap S extends in the rotational axis direction D. The permanent magnet 25 is inserted into the gap S. That is, the permanent magnet 25 is disposed within the gap S. In this embodiment, when the permanent magnet 25 is divided into three equal intervals in the rotational axis direction D, the temperature sensing element 51 abuts against the portion of the central section in the rotational axis direction D. 【0050】Figure 7 is a schematic diagram showing the contact configuration of the temperature-sensing element 51. As shown in Figure 7, the temperature-sensing element 51 is in contact with the side surface 25A of the permanent magnet 25 by a positioning member (resin member) 57. The positioning member 57 positions the temperature-sensing element 51 so that it is in contact with the side surface 25A of the permanent magnet 25. The positioning member 57 presses the temperature-sensing element 51 toward the permanent magnet 25. The positioning member 57 may be a resin sheet. The resin sheet may be, for example, a resin containing a foaming agent. The resin sheet may be, for example, a thermally expanding sheet that expands due to heat. 【0051】 Figure 8 is a schematic diagram showing the contact configuration of the temperature-sensing element 51. As shown in Figure 8, the positioning member (metal member) 58 may be, for example, a leaf spring. In this case, the leaf spring is provided between the rotor core 23 that defines the gap S and the temperature-sensing element 51, and biases the temperature-sensing element 51 relative to the rotor core 23. 【0052】 Next, we will explain how to manufacture the rotor 20. 【0053】 First, an element unit 50 is obtained by integrating the coil 52 and the substrate 55 with a housing 53 (sealing step). Specifically, the coil 52 is mounted on the substrate 55, and the substrate 55 and the temperature sensing element 51 are connected by wiring 54. Next, the coil 52 and the substrate 55 are housed in a resin case and filled with resin. This completes the housing 53, integrating the coil 52 and the substrate 55. 【0054】 Next, the element unit 50 is attached to the axial end face 23A of the rotor core 23 (attachment step). Specifically, the temperature-sensing element 51 and the positioning member 57 are inserted into the gap S of the rotor core 23. The positioning member 57 causes the temperature-sensing element 51 to come into contact with the side surface 25A of the permanent magnet 25 due to thermal expansion. Next, the housing 53 of the element unit 50 is fixed to the rotor core 23 using the mounting fixture 56. This attaches the element unit 50 to the rotor core 23. The rotor 20 is then manufactured. 【0055】Furthermore, the mounting position of the housing 53 on the rotor core 23 is not limited to being near the permanent magnet 25 (gap S), as shown in Figure 4. The mounting position of the housing 53 may be closer to the shaft 21. 【0056】 A rotating electric motor (MT) may be installed in an electric vehicle. Figure 9 is a schematic diagram showing the configuration of an electric vehicle. As shown in Figure 9, the electric vehicle 200 includes a rotating electric motor (MT), a battery 210, a power converter 220, a gear 230, an axle 240, and wheels 250. The electric vehicle 200 is powered by the driving force from the rotating electric motor (MT). 【0057】 When the electric vehicle 200 is driven by the rotating electric motor MT, the battery 210 supplies DC power to the power converter 220. The power converter 220 converts the DC power from the battery 210 into AC power and supplies the converted AC power to the rotating electric motor MT. 【0058】 When the electric vehicle 200 performs regenerative braking, the rotating electric motor MT generates alternating current (AC) power in accordance with the vehicle's kinetic energy, and this AC power is supplied to the power converter 220. The power converter 220 converts the AC power from the rotating electric motor MT into DC power and supplies the converted DC power to the battery 210. 【0059】 The rotational torque from the rotating electric motor MT is transmitted to the wheel 250 via the gear 230 and the axle 240. In a modified version of this embodiment, the rotational torque from the rotating electric motor MT may be transmitted to the wheel 250 by a different torque transmission configuration. 【0060】 When a rotor or rotating electric machine according to one aspect of this disclosure is mounted on an automobile, the operating time of the cooling system for temperature control of the rotating electric machine (MT) can be appropriately controlled, and the operating time of the cooling system can be reduced. As a result, the power consumption of the automobile can be reduced. 【0061】As described above, in the manufacturing method of the rotor 20 according to this embodiment, the temperature-sensing element 51 is mounted in the mounting step so as to contact the side surface 25A of the permanent magnet 25 in the gap S of the rotor core 23. As a result, the electrical resistance of the temperature-sensing element 51 changes in accordance with the temperature at the side surface 25A (a position closer to the center of the permanent magnet 25), which is less efficient at dissipating heat than the end surface 25B of the permanent magnet 25. In this way, the temperature-sensing element 51 can detect the temperature of the region of the permanent magnet 25 that is less efficient at dissipating heat. Therefore, temperature information of a predetermined part of the permanent magnet 25 can be obtained with high accuracy. 【0062】 In the manufacturing method of the rotor 20 according to this embodiment, in the mounting step, a positioning member 57 that has thermal expansion properties is provided in the gap S to position the temperature-sensing element 51 so that it contacts the side surface 25A of the permanent magnet 25, and the thermal expansion of the positioning member 57 causes the temperature-sensing element 51 to come into contact with the side surface 25A of the permanent magnet 25. In this method, contact between the temperature-sensing element 51 and the permanent magnet 25 is ensured, and the temperature of the permanent magnet 25 is detected more accurately. 【0063】 In the manufacturing method of the rotor 20 according to this embodiment, in the mounting step, a positioning member 57 is provided in the gap S to position the temperature-sensing element 51 so that it contacts the side surface 25A of the permanent magnet 25. This positioning member 57 is elastic and the elastic force of the positioning member 57 causes the temperature-sensing element 51 to come into contact with the side surface 25A of the permanent magnet 25. In this method, contact between the temperature-sensing element 51 and the permanent magnet 25 is ensured, and the temperature of the permanent magnet 25 is detected more accurately. 【0064】 The method for manufacturing the rotor 20 according to this embodiment includes a sealing step to obtain an element unit 50 in which the coil 52 is sealed by a housing 53. By sealing the coil 52 by the housing 53 in this way, an element unit 50 can be manufactured that can suppress component detachment, wire breakage, and ingress of cooling oil. Furthermore, by sealing the coil 52 by the housing 53, damage to components can be avoided when attaching the element unit 50 to the rotor core 23. 【0065】While embodiments of this disclosure have been described above, this disclosure is not necessarily limited to the embodiments described above, and various modifications are possible without departing from its essence. 【0066】 In the above embodiment, a configuration in which the rotor 20 is equipped with a permanent magnet 25 was described as an example. However, the magnet is not limited to a permanent magnet, and may be, for example, an electromagnet. 【0067】As can be understood from the above-described embodiments and modifications, this specification includes the following disclosures: (Note 1) A method for manufacturing a rotor comprising a rotor core, magnets disposed in the gaps of the rotor core, and a temperature information transmitting device for transmitting temperature information relating to the temperature of the magnets, wherein the temperature information transmitting device comprises a thermosensitive element whose electrical resistance changes according to temperature, and a coil electrically connected to the thermosensitive element, and includes a mounting step of attaching the temperature information transmitting device to the rotor core, wherein the mounting step involves attaching the thermosensitive element so as to contact the side surface of the magnets in the gaps of the rotor core. (Note 2) The method for manufacturing a rotor according to Note 1, wherein the mounting step involves providing a resin member that has thermal expandability in the gap for positioning the thermosensitive element so as to contact the side surface of the magnets, and the thermal expansion of the resin member causes the thermosensitive element to contact the side surface of the magnets. (Note 3) The method for manufacturing a rotor according to Note 1, wherein in the mounting step, a metal member having elasticity is provided in the gap for positioning the temperature-sensing element so that the temperature-sensing element contacts the side surface of the magnet, and the elastic force of the metal member causes the temperature-sensing element to come into contact with the side surface of the magnet. (Note 4) The method for manufacturing a rotor according to any one of Notes 1 to 3, wherein the temperature-sensing element and the coil are electrically connected using substrate wiring or wire wrapping. (Note 5) The method for manufacturing a rotor according to any one of Notes 1 to 4, further comprising a sealing step to obtain the temperature information transmitting device in which the coil is sealed with a sealing member. (Note 6) A rotor comprising: a rotor core; magnets disposed within the gaps of the rotor core; and a temperature information transmitting device for transmitting temperature information relating to the temperature of the magnets, wherein the temperature information transmitting device comprises a temperature-sensing element whose electrical resistance changes according to temperature, and a coil electrically connected to the temperature-sensing element, and the temperature-sensing element is in contact with the side surface of the magnets within the gaps of the rotor core.(Note 7) The rotor according to Note 6, further comprising a positioning member for positioning the temperature sensing element so that the temperature sensing element contacts the side surface of the magnet, wherein the positioning member presses the temperature sensing element toward the magnet. (Note 8) A rotating electric machine comprising the rotor according to Note 6 or Note 7, a stator, and a temperature information receiving device attached to the stator for receiving the temperature information transmitted from the temperature information transmitting device. (Note 9) An automobile comprising the rotating electric machine according to Note 8. 【0068】 10...Stator, 20...Rotor, 23...Rotor core, 23A...End face, 25...Permanent magnet, 25A...Side, 50...Element unit (temperature information transmitting device), 51...Temperature sensing element, 52...Coil, 53...Housing (sealing member), 56...Mounting fixture, 57...Positioning member (resin member), 58...Positioning member (metal member), 60...Element unit (temperature information receiving device), 200...Electric vehicle (automobile), MT...Rotating electric machine.

Claims

1. A method for manufacturing a rotor, comprising a rotor core, magnets disposed within the gaps of the rotor core, and a temperature information transmitting device for transmitting temperature information relating to the temperature of the magnets, wherein the temperature information transmitting device comprises a temperature-sensing element whose electrical resistance changes according to temperature, and a coil electrically connected to the temperature-sensing element, and the method includes a mounting step of attaching the temperature information transmitting device to the rotor core, wherein the mounting step involves attaching the temperature-sensing element so as to contact the side surface of the magnets in the gaps of the rotor core.

2. The method for manufacturing a rotor according to claim 1, wherein in the mounting step, a resin member for positioning the temperature-sensing element so that the temperature-sensing element contacts the side surface of the magnet is provided in the gap, the resin member having thermal expandability is provided, and the temperature-sensing element is brought into contact with the side surface of the magnet by the thermal expansion of the resin member.

3. The method for manufacturing a rotor according to claim 1, wherein in the mounting step, a metal member for positioning the temperature-sensing element so that the temperature-sensing element contacts the side surface of the magnet is provided in the gap, the elastic metal member is provided, and the temperature-sensing element is brought into contact with the side surface of the magnet by the elastic force of the metal member.

4. The method for manufacturing a rotor according to claim 1 or 2, wherein the temperature sensing element and the coil are electrically connected using circuit board wiring or wire wrapping.

5. A method for manufacturing a rotor according to claim 1 or 2, comprising a sealing step to obtain the temperature information transmitting device in which the coil is sealed with a sealing member.

6. A rotor comprising: a rotor core; magnets disposed within the gaps of the rotor core; and a temperature information transmitting device for transmitting temperature information relating to the temperature of the magnets, wherein the temperature information transmitting device comprises a temperature-sensing element whose electrical resistance changes according to temperature, and a coil electrically connected to the temperature-sensing element, and the temperature-sensing element is in contact with the side surface of the magnets within the gaps of the rotor core.

7. The rotor according to claim 6, further comprising a positioning member for positioning the temperature-sensing element so that it contacts the side surface of the magnet, wherein the positioning member presses the temperature-sensing element toward the magnet.

8. A rotating electric machine comprising: the rotor according to claim 6; a stator; and a temperature information receiving device attached to the stator and receiving the temperature information transmitted from the temperature information transmitting device.

9. An automobile comprising the rotating electric machine described in claim 8.

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