Electric motor

Abstract

To provide an electric motor in which strength deterioration of a bobbin can be suppressed.SOLUTION: An electric motor 10 includes a coil 41 formed by winding a winding wire 40 having a terminal connection portion 43 wound around a tooth 32, and an insulating first bobbin 50a disposed on a first end surface 30a of a stator core 30 and disposed between the tooth 32 and the coil 41. A plurality of through holes passing in a radial direction of a yoke 31 between the tooth 32 and the coil 41 is disposed in the first bobbin 50a. Each of the through holes has a shape corresponding to both a thread hole into which a lacing thread 14 is inserted, and a sensor hole into which a thermistor 15 is inserted. The winding wire 40 has a lead-out portion 42 that is led out from the coil 41 and extends between the coil 41 and the terminal connection portion 43. The thermistor 15 is disposed to be inserted in a through hole, among the plurality of through holes, positioned closest to a position where the lead-out portion 42 is led out from the coil 41.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electric motor. [Background technology]

[0002] The electric motor includes a rotor, a stator core, and a coil. The rotor is fixed to a rotating shaft and rotates integrally with the rotating shaft. The stator core has a cylindrical yoke extending in the axial direction of the rotating shaft and a plurality of teeth extending from the inner peripheral surface of the yoke toward the rotor. The coil is formed by winding a wire having a terminal connection portion around each of the plurality of teeth. The coil has coil ends protruding from an axial end face of the stator core.

[0003] Patent Document 1 discloses a rotating electric machine including a lacing yarn for forming a coil end, a thermistor for detecting the temperature of the coil, and a mounting member for mounting the thermistor to the coil. The lacing yarn is inserted through a cuff provided between an axial end face of a stator core and the coil end. The thermistor is mounted to the mounting member. The mounting member is mounted to the coil. In other words, the thermistor is mounted to the coil via the mounting member.

[0004] Patent Document 2 discloses a rotating electric machine including an insulating bobbin that is disposed on an axial end surface of a stator core and is provided between the teeth and a coil portion. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2008-178222 A [Patent Document 2] JP 2010-213392 A Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, the structure for inserting the lacing yarn and the structure for attaching the thermistor are provided separately, which complicates the structure of the electric motor. In order to simplify the structure of the electric motor, for example, it is conceivable to provide a thread hole dedicated to the lacing yarn through which the lacing yarn is inserted and a sensor hole dedicated to the thermistor for attaching the thermistor to each of the multiple bobbin structures divided in the circumferential direction of the yoke. In this case, the structure for inserting the lacing yarn and the structure for attaching the thermistor are integrated in the bobbin, which simplifies the structure of the electric motor. However, when the bobbin structures are connected in the circumferential direction to form the bobbin, the number of thread holes and sensor holes becomes the same, which results in the formation of a sensor hole to which the thermistor cannot be attached, thereby reducing the strength of the bobbin. [Means for solving the problem]

[0007] The electric motor for solving the above problems includes a rotor fixed to a rotating shaft and rotating integrally with the rotating shaft, a stator core having a cylindrical yoke extending in the axial direction of the rotating shaft and a plurality of teeth extending from an inner peripheral surface of the yoke toward the rotor, a coil formed by winding a wire having a terminal connection portion around each of the teeth, an insulating bobbin disposed on an end surface of the stator core in the axial direction and provided between the teeth and the coil, a lacing thread for forming a coil end that is a portion of the coil protruding from the end surface of the stator core in the axial direction, and a temperature control circuit for controlling the temperature control of the coil. and a thermistor for detecting a temperature of the coil, wherein the bobbin has a plurality of through holes between each of the teeth and the coil that penetrate the yoke in the radial direction, the through holes having shapes that correspond to both a thread hole through which the racing thread is inserted and a sensor hole through which the thermistor is inserted, the winding is pulled out from the coil and has a pull-out portion extending between the coil and the terminal connection portion, and the thermistor is inserted into the through hole that is closest to the position through which the pull-out portion from the coil is pulled out.

[0008] Since the through hole has a shape corresponding to both the thread hole and the sensor hole, it is not necessary to provide a thread hole and a sensor hole in the bobbin, and therefore a decrease in the strength of the bobbin can be suppressed. In the above electric motor, the through hole may have a first hole portion that functions as the thread hole or the sensor hole, and a second hole portion that functions only as the thread hole, the diameter of the first hole portion being larger than the diameter of the second hole portion, the first hole portion opening to the radially outward side and the second hole portion opening to the radially inward side, and the first hole portion being located radially outward than the second hole portion.

[0009] The thermistor is inserted into a first hole of the through hole from the radially outer side. A second hole having a smaller diameter than the first hole is provided radially inward from the first hole. The thermistor is positioned in the radial direction by the second hole.

[0010] In the above electric motor, the thermistor may be fixed to the sensor hole by a resin mold. The thermistor is less likely to fall out of the sensor hole. Also, because heat from the coil is transferred to the thermistor via the resin, heat from the coil is more easily transferred to the thermistor than when the thermistor is simply inserted into the sensor hole and not fixed with a resin mold. Effect of the Invention

[0011] According to the present invention, the decrease in strength of the bobbin can be suppressed. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a plan view of the electric motor according to the embodiment. [Diagram 2] 2 is an exploded perspective view showing a portion of a stator core, a first bobbin, and a second bobbin. FIG. [Diagram 3] 3 is a cross-sectional view taken along line 3-3 in FIG. 1. [Figure 4] 4 is a cross-sectional view taken along line 4-4 in FIG. [Diagram 5]FIG. 2 is a side view of the core assembly and the bobbin assembly. [Figure 6] FIG. 2 is a cross-sectional view of a core structure and a bobbin structure. [Figure 7] FIG. 11 is a partial cross-sectional view of a stator according to a modified example. [Figure 8] FIG. 11 is a partial side view of a stator according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, one embodiment of the electric motor will be described with reference to Figs. As shown in FIG. 1, the electric motor 10 includes a rotating shaft 11, a rotor 12, a stator 13, a lacing yarn 14, and a thermistor 15.

[0014] <Rotor> The rotor 12 has a cylindrical rotor core 21 and a plurality of permanent magnets 22. The rotor core 21 has a plurality of magnet accommodating holes 21a penetrating the rotor core 21 in the axial direction. The plurality of magnet accommodating holes 21a are arranged in the circumferential direction of the rotor core 21. The permanent magnets 22 are accommodated in the magnet accommodating holes 21a. The rotor 12 of this embodiment is an IPM (Interior Permanent Magnet) type rotor in which the permanent magnets 22 are embedded inside the rotor core 21. The rotating shaft 11 is inserted inside the rotor core 21. The rotor 12 is fixed to the rotating shaft 11. The rotor 12 rotates integrally with the rotating shaft 11.

[0015] <Stator> The stator 13 is disposed on the outside of the rotor 12. The stator 13 has a stator core 30, U-phase, V-phase, and W-phase windings 40, and a first bobbin 50a and a second bobbin 50b (see FIG. 2) serving as insulating bobbins. The windings 40 are composed of a conductor and an insulating coating that covers the conductor. The first bobbin 50a and the second bobbin 50b are formed from an insulating material.

[0016] The stator core 30 has a yoke 31 and a plurality of teeth 32. The stator core 30 of this embodiment has twelve teeth 32 as the plurality of teeth 32. The yoke 31 has a cylindrical shape extending in the axial direction of the rotating shaft 11. Hereinafter, the axial direction, radial direction, and circumferential direction of the yoke 31 are also referred to as the axial direction, radial direction, and circumferential direction of the stator core 30, respectively. The plurality of teeth 32 extend from an inner peripheral surface of the yoke 31 toward the rotor 12. The plurality of teeth 32 are disposed at equal intervals in the circumferential direction of the yoke 31.

[0017] As shown in FIG. 2, the stator core 30 is formed by a plurality of core constituent bodies 300. The stator core 30 of this embodiment is formed by twelve core constituent bodies 300. The core constituent body 300 has a plate-shaped yoke constituent part 301 and teeth 32. The yoke constituent part 301 has a first surface that is concavely curved and a second surface that is a surface opposite to the first surface in the plate thickness direction and is convexly curved. The teeth 32 extend from the first surface of the yoke constituent part 301. The stator core 30 is formed by arranging a plurality of core constituent bodies 300 in an annular shape. The yoke 31 is formed by arranging a plurality of yoke constituent parts 301 in an annular shape.

[0018] The stator core 30 has a first end face 30a and a second end face 30b. The first end face 30a and the second end face 30b are each an axial end face of the stator core 30. The second end face 30b is located opposite the first end face 30a in the axial direction of the stator core 30.

[0019] 2, the axial dimension of the stator core 30 is illustrated as being shorter than the actual dimension. The actual axial dimension of the stator core 30 is approximately the sum of the dimension of a second insulating portion 52b of a first bobbin 50a and the dimension of a second insulating portion 52b of a second bobbin 50b, which will be described later.

[0020] 1, the winding 40 is wound around each of the multiple teeth 32 to form a coil 41. In this embodiment, twelve coils 41 are formed. The winding 40 is wound around the teeth 32 in a concentrated winding manner.

[0021] 3 and 4, the coil 41 has a first coil end 41a that protrudes in the axial direction of the stator core 30 from the first end face 30a of the stator core 30. Although not shown, the coil 41 has a second coil end that protrudes in the axial direction of the stator core 30 from the second end face 30b of the stator core 30. As will be described later, the first coil end 41a and the second coil end are each formed from a lacing yarn 14.

[0022] As shown in FIG. 1, the winding 40 has a lead-out portion 42. The lead-out portion 42 is a portion led out from the coil 41 at the first coil end 41a. Of the twelve coils 41, the coils 41 from which the lead-out portions 42 of the U-phase, V-phase, and W-phase are led out are referred to as a U-phase lead-out coil 41u, a V-phase lead-out coil 41v, and a W-phase lead-out coil 41w, respectively. A part of the lead-out portion 42 is covered by an insulating tube 16. In addition, the ends of the lead-out portions 42 of the U-phase, V-phase, and W-phase are connected to the terminal connection portion 43 of the same phase with the insulating coating removed. That is, the winding 40 has the terminal connection portion 43. The lead-out portion 42 is a portion extending between the coil 41 and the terminal connection portion 43. The terminal connection portion 43 is connected to a metal terminal not shown.

[0023] 2, the first bobbin 50a is composed of a plurality of bobbin assemblies 51. The second bobbin 50b is composed of a plurality of bobbin assemblies 51. In this embodiment, the number of the bobbin assemblies 51 constituting the first bobbin 50a and the number of the bobbin assemblies 51 constituting the second bobbin 50b are the same as the number of the teeth 32. That is, each of the first bobbin 50a and the second bobbin 50b in this embodiment is composed of 12 bobbin assemblies 51.

[0024] The bobbin component 51 constituting the first bobbin 50a and the bobbin component 51 constituting the second bobbin 50b have the same shape. The bobbin component 51 has a U-shaped tooth insulating portion 52 and a pair of plate-shaped yoke insulating portions 53.

[0025] The tooth insulating portion 52 has a first insulating portion 52a and a pair of second insulating portions 52b. The first insulating portion 52a is rectangular plate-shaped. The pair of second insulating portions 52b extend from a pair of edges of the first insulating portion 52a in the plate thickness direction of the first insulating portion 52a. The tooth insulating portion 52 has a plate portion 54 provided at an end of the first insulating portion 52a. The plate thickness direction of the plate portion 54 is perpendicular to both the plate thickness direction of the first insulating portion 52a and the plate thickness direction of the second insulating portion 52b. The plate portion 54 extends in a direction opposite to the direction in which the second insulating portion 52b extends from the first insulating portion 52a. The plate portion 54 has a groove 54b recessed from a tip surface 54a.

[0026] The pair of yoke insulating parts 53 extend in directions away from each other from the pair of second insulating parts 52b. The pair of yoke insulating parts 53 are located at the end of the tooth insulating part 52 opposite the end where the plate part 54 is provided. The plate thickness direction of the pair of yoke insulating parts 53 substantially coincides with the plate thickness direction of the plate part 54.

[0027] The bobbin assembly 51 of the first bobbin 50a is attached to the stator core 30 from the first end face 30a side of the stator core 30. The first bobbin 50a is disposed on the first end face 30a of the stator core 30. The bobbin assembly 51 of the second bobbin 50b is attached to the stator core 30 from the second end face 30b side of the stator core 30. The second bobbin 50b is disposed on the second end face 30b of the stator core 30. The winding 40 is wound around the teeth 32 of the stator core 30 to which the first bobbin 50a and the second bobbin 50b are attached.

[0028] 3 and 4, the first insulating portion 52a of the first bobbin 50a is provided between the teeth 32 and the first coil end 41a at the first end face 30a of the stator core 30. Although not shown, the first insulating portion 52a of the second bobbin 50b is provided between the teeth 32 and the second coil end at the second end face 30b of the stator core 30. The pair of second insulating portions 52b of the first bobbin 50a and the second bobbin 50b are provided between the coil 41 and both end faces of the teeth 32 in the circumferential direction of the stator core 30. The tooth insulating portion 52 insulates the teeth 32 from the coil 41.

[0029] 1, the pair of yoke insulating parts 53 of the first bobbin 50a are provided between the inner peripheral surface of the yoke 31 and the coil 41. The pair of yoke insulating parts 53 of the second bobbin 50b are provided between the inner peripheral surface of the yoke 31 and the coil 41. The pair of yoke insulating parts 53 insulate the yoke 31 from the coil 41.

[0030] 3 and 4, the plate portion 54 of the first bobbin 50a extends from the first end surface 30a of the stator core 30. Parts of the pair of yoke insulating portions 53 of the first bobbin 50a protrude from the first end surface 30a of the stator core 30. The first coil end 41a is located between the plate portion 54 and the pair of yoke insulating portions 53 in the radial direction of the stator core 30.

[0031] Although not shown, the plate portion 54 of the second bobbin 50b extends from the second end face 30b of the stator core 30. Parts of the pair of yoke insulating portions 53 of the second bobbin 50b protrude from the second end face 30b of the stator core 30. The second coil end is located between the plate portion 54 and the pair of yoke insulating portions 53 in the radial direction of the stator core 30.

[0032] 5, each yoke insulating part 53 has two protruding parts 53a protruding from the radially outer surface at a part protruding from the first end face 30a of the stator core 30. The two protruding parts 53a extend in parallel along the circumferential direction of the stator core 30.

[0033] 5 and 6, each tooth insulating portion 52 has a through hole 56 that penetrates the first insulating portion 52a in the radial direction of the stator core 30. Thus, the first bobbin 50a and the second bobbin 50b each have a plurality of through holes 56 that penetrate in the radial direction of the yoke 31 between each tooth 32 and the coil 41. The through holes 56 have a shape that corresponds to both a thread hole through which the lacing yarn 14 is inserted and a sensor hole through which the thermistor 15 is inserted.

[0034] The through hole 56 is composed of a first hole portion 56a and a second hole portion 56b. The first hole portion 56a is a square hole that opens to the radially outer side of the stator core 30. The second hole portion 56b is a round hole that opens to the radially inner side of the stator core 30. The first hole portion 56a is provided on the outer side of the second hole portion 56b in the radial direction of the stator core 30.

[0035] The diameter of the first hole portion 56a is larger than the diameter of the second hole portion 56b. In other words, the diameter of the through hole 56 is larger on the outside than on the inside in the radial direction of the stator core 30. Specifically, the diameter of the first hole portion 56a is set to a diameter that allows the thermistor 15 to be inserted. The thermistor 15 is thicker than the lacing yarn 14. Therefore, when the diameter of the first hole portion 56a is a diameter that allows the thermistor 15 to be inserted, the lacing yarn 14 can also be inserted into the first hole portion 56a. The diameter of the second hole portion 56b is set to a diameter that does not allow the thermistor 15 to be inserted but allows the lacing yarn 14 to be inserted.

[0036] The surfaces defining the through hole 56 include a first inner circumferential surface 561 defining the first hole portion 56a, a second inner circumferential surface 562 defining the second hole portion 56b, and a connection surface 563 connecting the first inner circumferential surface 561 and the second inner circumferential surface 562. The connection surface 563 is a surface perpendicular to the radial direction of the stator core 30.

[0037] <Lacing yarn> As shown in FIG. 3, the lacing yarn 14 surrounds the first coil end 41a. The lacing yarn 14 has first to fourth regions 14a to 14d. The first region 14a is a portion inserted into the through hole 56 of the first insulating portion 52a. The first region 14a is inserted into both the first hole portion 56a and the second hole portion 56b of the through hole 56. The first region 14a extends along the radial direction of the stator core 30 between the first end face 30a of the stator core 30 and the first coil end 41a. The second region 14b extends in the radial direction of the stator core 30 on the opposite side of the stator core 30 across the first coil end 41a in the axial direction of the stator core 30. The third region 14c is a portion that connects the first region 14a and the second region 14b radially inward of the plate portion 54. The connection portion between the second portion 14b and the third portion 14c passes through a groove 54b in the plate portion 54. The fourth portion 14d is a portion that connects the first portion 14a and the second portion 14b radially outward of the pair of yoke insulating portions 53. The fourth portion 14d is located between the pair of yoke insulating portions 53. In this manner, the racing yarn 14 surrounds the first coil end 41a, thereby forming the first coil end 41a so that the winding 40 does not rise up from the first coil end 41a.

[0038] In this embodiment, the racing yarn 14 forms the first coil ends 41a of eleven of the twelve coils 41. Therefore, the racing yarn 14 is inserted into eleven of the twelve through holes 56 of the first bobbin 50a. The racing yarn 14 of this embodiment forms the first coil ends 41a of nine coils 41 whose drawn-out portions 42 are not drawn out, the U-phase drawn-out coil 41u, and the W-phase drawn-out coil 41w. Therefore, the racing yarn 14 is inserted into the through holes 56 located near the nine coils 41 whose drawn-out portions 42 are not drawn out, the U-phase drawn-out coil 41u, and the W-phase drawn-out coil 41w, among the twelve through holes 56 of the first bobbin 50a.

[0039] Although not shown, the lacing yarn 14 surrounds the second coil end to form the second coil end. The configuration of the lacing yarn 14 that forms the second coil end is the same as that of the lacing yarn 14 that forms the first coil end 41a, so a detailed description will be omitted. The lacing yarn 14 forms the second coil ends of the twelve coils 41. Therefore, the lacing yarn 14 is inserted into each of the twelve through holes 56 of the second bobbin 50b.

[0040] <Thermistor> 4, the thermistor 15 has a sensor portion 15a that detects the temperature of the coil 41 and a wiring portion 15b extending from the sensor portion 15a. The sensor portion 15a is inserted into one of the through holes 56 of the first bobbin 50a through which the lacing yarn 14 is not inserted. In this embodiment, of the twelve through holes 56 of the first bobbin 50a, the through hole 56 located at a position corresponding to the V-phase lead coil 41v is the through hole 56 through which the lacing yarn 14 is not inserted.

[0041] That is, of the twelve through holes 56 of the same shape that the first bobbin 50a has, eleven of the through holes 56 function as thread holes through which the racing yarn 14 is inserted, and the remaining through hole 56 functions as a sensor hole through which the thermistor 15 is inserted. In this manner, the through holes 56 of the first bobbin 50a function as thread holes or sensor holes. That is, the through holes 56 of the first bobbin 50a correspond to both thread holes and sensor holes. In addition, the thermistor 15 is inserted and disposed in the through hole 56 that is located closest to the position where the lead-out portion 42 from the V-phase lead-out coil 41v is led out among the multiple through holes 56.

[0042] The sensor portion 15a is inserted into the first hole portion 56a of the through hole 56 from the radial outside of the stator core 30. As described above, the second hole portion 56b, which has a smaller diameter than the first hole portion 56a, is provided radially inward from the first hole portion 56a. For this reason, the thermistor 15 is not inserted into the second hole portion 56b. In this embodiment, the tip surface of the sensor portion 15a contacts the connection surface 563 of the through hole 56, thereby restricting the radially inward movement of the thermistor 15. On the other hand, the racing yarn 14 is inserted into both the first hole portion 56a and the second hole portion 56b of the through hole 56. In this way, the first hole portion 56a functions as both a thread hole and a sensor hole, whereas the second hole portion 56b functions as a thread hole but does not function as a sensor hole.

[0043] The electric motor 10 is accommodated in a cylindrical housing (not shown). The stator 13, the lacing yarn 14, and the thermistor 15 are resin-molded after the stator core 30 is shrink-fitted into the housing. Note that the drawn-out portion 42 of the winding 40 and the wiring portion 15b of the thermistor 15 are not resin-molded.

[0044] 4, resin 17 flows into through hole 56. Therefore, sensor portion 15a of thermistor 15 is fixed to through hole 56 by the resin mold. [Actions and Effects of the Present Embodiment] The operation and effects of this embodiment will be described.

[0045] (1) The first bobbin 50a is provided with a plurality of through holes 56 that penetrate the yoke 31 in the radial direction between the teeth 32 and the coil 41. The through holes 56 have shapes that correspond to both thread holes through which the racing yarn 14 is inserted and thermistor holes through which the thermistor 15 is inserted. This eliminates the need to provide thread holes and sensor holes in the first bobbin 50a. This prevents the strength of the first bobbin 50a from decreasing.

[0046] (2) The through hole 56 has a first hole portion 56a that functions as a thread hole or a sensor hole, and a second hole portion 56b that functions only as a thread hole. The diameter of the first hole portion 56a is larger than the diameter of the second hole portion 56b. The first hole portion 56a opens radially outward. The second hole portion 56b opens radially inward. The first hole portion 56a is provided radially outward of the second hole portion 56b.

[0047] The thermistor 15 is inserted into a first hole 56a of the through hole 56 from the radial outside of the stator core 30. A second hole 56b having a diameter smaller than that of the first hole 56a is provided radially inward of the first hole 56a. The thermistor 15 is positioned in the radial direction by the second hole 56b. Thus, the thermistor 15 can be disposed in a desired position suitable for detecting the temperature of the coil 41.

[0048] (3) Thermistor 15 is fixed to through hole 56 with a resin mold. This makes it difficult for thermistor 15 to fall out of through hole 56. In addition, since heat from coil 41 is transferred to thermistor 15 via resin 17, heat from coil 41 is more easily transferred to thermistor 15 than when thermistor 15 is simply inserted into through hole 56 and is not fixed with a resin mold.

[0049] (4) The thermistor 15 is inserted through the through hole 56 that is closest to the position where the lead-out portion 42 from the V-phase lead-out coil 41v is led out of the multiple through holes 56. Therefore, the lead-out portion 42 and the wiring portion 15b of the thermistor 15 extend from approximately the same position in the circumferential direction of the stator core 30. Therefore, compared to a case where the lead-out portion 42 and the wiring portion 15b of the thermistor 15 extend from different positions in the circumferential direction of the stator core 30, the lead-out portion 42 and the wiring portion 15b of the thermistor 15 can be easily handled.

[0050] (5) The thermistor 15 is attached to the first bobbin 50a, which is an existing component of the electric motor 10. Therefore, there is no need to provide a new attachment part for attaching the thermistor 15. This makes it possible to prevent the configuration of the electric motor 10 from becoming complicated.

[0051] (6) As a method for suppressing the decrease in strength of the first bobbin 50a, for example, the following method is conceivable. Among the multiple bobbin constructs 51, a bobbin construct 51 into which the thermistor 15 is inserted is determined in advance. Then, a thread hole and a sensor hole are formed in the bobbin construct 51, and only a thread hole is formed in the other bobbin constructs 51. In this case, only one bobbin construct 51 having two holes formed therein is required, so that the decrease in strength of the first bobbin 50a can be suppressed. However, both a bobbin construct 51 having only a thread hole formed therein and a bobbin construct 51 having a thread hole and a sensor hole formed therein are required. In this case, two types of molding dies for the bobbin construct 51 are prepared, or a bobbin construct 51 having a thread hole formed therein is required to be processed to form a sensor hole. In contrast, in this embodiment, all of the bobbin constructs 51 have the same shape. Therefore, only one type of molding die for the bobbin construct 51 is required, and processing of the bobbin construct 51 is not required.

[0052] [Example of change] The above-described embodiments can be modified as follows: The above-described embodiments and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

[0053] The configuration of the first bobbin 50a may be modified as appropriate. However, the first bobbin 50a is arranged on the first end surface 30a of the stator core 30 and is provided between the teeth 32 and the coil 41.

[0054] As an example, the bobbin construct 51 may have only the first insulating portion 52a of the tooth insulating portion 52. In this case, insulation between the coil 41 and both end faces of the teeth 32 in the circumferential direction of the stator core 30, and between the inner circumferential surface of the yoke 31 and the coil 41 are provided by an insulating member separate from the bobbin construct 51.

[0055] As another example, the first bobbin 50a may have a cylindrical portion and a plurality of extension portions extending from an inner peripheral surface of the cylindrical portion toward the rotor 12. The first bobbin 50a is disposed on the first end face 30a of the stator core 30. The cylindrical portion covers the yoke 31 at the first end face 30a of the stator core 30. The extension portions are provided between the teeth 32 and the coils 41 at the first end face 30a of the stator core 30. Each extension portion is provided with a through hole 56 that penetrates the extension portion in the radial direction. Therefore, the first bobbin 50a has a plurality of through holes 56 that penetrate the yoke 31 in the radial direction between each tooth 32 and the coil 41.

[0056] Instead of being inserted through the through hole 56 located closest to the position where the lead-out portion 42 from the V-phase lead-out coil 41v is pulled out, the thermistor 15 may be inserted through the through hole 56 located closest to the position where the lead-out portion 42 from the U-phase lead-out coil 41u is pulled out. In this case, the lacing yarn 14 is inserted through the through hole 56 located closest to the position where the lead-out portion 42 from the V-phase lead-out coil 41v is pulled out, thereby forming the first coil end 41a of the V-phase lead-out coil 41v.

[0057] Instead of being inserted through the through hole 56 located closest to the position where the lead-out portion 42 from the V-phase lead-out coil 41v is pulled out, the thermistor 15 may be inserted through the through hole 56 located closest to the position where the lead-out portion 42 from the W-phase lead-out coil 41w is pulled out. In this case, the lacing yarn 14 is inserted through the through hole 56 located closest to the position where the lead-out portion 42 from the V-phase lead-out coil 41v is pulled out, thereby forming the first coil end 41a of the V-phase lead-out coil 41v.

[0058] The diameter of the first hole 56a may be the same as the diameter of the second hole 56b. The diameter of the through hole 56 may gradually decrease from the outer side to the inner side in the radial direction of the stator core 30 .

[0059] The first hole portion 56a does not have to be a round hole as long as the lacing yarn 14 can be inserted therethrough. The second hole 56b does not have to be a square hole as long as the thermistor 15 can be inserted therethrough. The stator 13, the lacing yarn 14, and thermistor 15 do not have to be resin molded. In other words, the thermistor 15 does not have to be fixed to the through hole 56 by a resin mold, but may simply be inserted into the through hole 56.

[0060] As shown in FIG. 7, the winding 40 may have a phase wire 44. The phase wire 44 is drawn out from the coil 41 at the first coil end 41a. The drawn-out portion 42 in the above embodiment is one end of the winding 40, and the phase wire 44 is the other end of the winding 40. The ends of the U-phase, V-phase, and W-phase phase wires 44 are electrically connected to each other by bundling them together with the insulating coating removed. The part where the U-phase, V-phase, and W-phase phase wires 44 are electrically connected to each other constitutes a neutral point. The neutral point is accommodated in an insulating case 18. The case 18 is disposed between the second portion 14b of the lacing yarn 14 and the first coil end 41a, and is fixed to the first coil end 41a.

[0061] The phase wire 44 may be pulled out from the coil 41 at the second coil end. In this case, the case 18 is fixed to the second coil end by being disposed between the lacing yarn 14 and the second coil end.

[0062] As shown in FIG. 8, the winding 40 has a crossover wire 45 that connects the coils 41 of the same phase that are adjacent in the circumferential direction of the stator core 30. The lacing yarn 14 may also be used to fix the crossover wire 45 to the first bobbin 50a. The crossover wire 45 is disposed between the fourth portion 14d of the lacing yarn 14 and a pair of yoke insulating parts 53. The crossover wire 45 extends along the circumferential direction of the yoke 31 by being guided by the protruding parts 53a of the pair of yoke insulating parts 53. In this case, the fourth portion 14d of the lacing yarn 14 may be laced obliquely to connect the first portion 14a and the second portion 14b adjacent to the first portion 14a in the circumferential direction of the stator core 30.

[0063] A known method can be used for lacing the lacing yarn 14. When lacing is automated, for example, a supply nozzle for supplying the lacing yarn 14 is disposed inside the stator 13. The supply nozzle is capable of reciprocating in the axial direction of the stator core 30. A needle is disposed outside the stator 13 and moves while gripping the lacing yarn 14 supplied from the supply nozzle. The needle is capable of reciprocating in the axial and radial directions of the stator core 30.

[0064] The tip of the supply nozzle and the tip of the needle are disposed at the same position as the through hole 56 in the axial direction of the stator core 30. The needle passes through the through hole 56 to move to the inside of the stator core 30, and then grips a middle portion of the lacing yarn 14 supplied from the supply nozzle. The needle, while gripping the lacing yarn 14, passes through the through hole 56 to move to the outside of the stator core 30. As a result, the lacing yarn 14 is inserted into the through hole 56.

[0065] The supply nozzle and the needle move in the axial direction of the stator core 30 so that their respective tips are positioned above the first coil end 41a in the axial direction of the stator core 30. The needle passes through the loop of the lacing yarn 14 that it is holding and moves to the inside of the stator core 30, and then newly holds the lacing yarn 14 supplied from the supply nozzle. With the lacing yarn 14 held, the needle passes through the through hole 56 and moves to the outside of the stator core 30. The needle then passes the lacing yarn 14 that it is holding through the loop of the lacing yarn 14.

[0066] The supply nozzle and the needle move in the axial direction of the stator core 30 so that their respective tips are located at the same position as the through hole 56 in the axial direction of the stator core 30. The needle passes through the loop of the lacing yarn 14 that it is holding and moves to the inside of the stator core 30, and then newly holds the lacing yarn 14 supplied from the supply nozzle. The needle, while holding the lacing yarn 14, moves to the outside of the stator core 30 by passing through the through hole 56. Then, the needle passes the lacing yarn 14 that it is holding through the loop of the lacing yarn 14.

[0067] The supply nozzle and needle repeat this operation, causing the lacing yarn 14 to form the first coil end 41a. The thermistor 15 detects the temperature of the coil 41 via the first bobbin 50a. In addition, since the thermistor 15 is disposed between the first coil end 41a and the stator core 30, it may also be affected by the temperature of the stator core 30. Therefore, by taking these factors into consideration and correcting the temperature detection result by the thermistor 15, the temperature of the coil 41 can be obtained more accurately.

[0068] The configuration of the rotor 12 may be changed as appropriate. For example, the rotor 12 may be a surface permanent magnet (SPM) type rotor in which the permanent magnets 22 are arranged on the outer circumferential surface of the rotor core 21.

[0069] The stator core 30 may be a stator core in which a plurality of core assemblies 300 are integrally formed. The first bobbin 50a may be a bobbin in which a plurality of bobbin assemblies 51 are integrally formed. The second bobbin 50b may be a bobbin in which a plurality of bobbin assemblies 51 are integrally formed. [Explanation of symbols]

[0070] 10...electric motor, 11...rotating shaft, 12...rotor, 14...lacing thread, 15...thermistor, 30...stator core, 30a...first end face as end face, 31...yoke, 32...teeth, 40...winding, 41...coil, 41a...first coil end as coil end, 42...pulling portion, 43...terminal connection portion, 50a...first bobbin as bobbin, 56...through hole, 56a...first hole portion, 56b...second hole portion.

Claims

1. A rotor fixed to a rotating shaft and rotating integrally with the rotating shaft; a stator core including a cylindrical yoke extending in an axial direction of the rotating shaft and a plurality of teeth extending from an inner peripheral surface of the yoke toward the rotor; a coil formed by winding a wire having a terminal connection portion around each of the plurality of teeth; an insulating bobbin disposed on an axial end surface of the stator core and provided between the teeth and the coil; A lacing thread that forms a coil end, which is a portion of the coil that protrudes from an end surface of the stator core in the axial direction; a thermistor for detecting the temperature of the coil; An electric motor comprising: The bobbin is provided with a plurality of through holes extending radially through the yoke between each of the teeth and the coil, the through hole has a shape corresponding to both a thread hole through which the lacing thread is inserted and a sensor hole through which the thermistor is inserted; the winding has a lead-out portion that is drawn out from the coil and extends between the coil and the terminal connection portion, an electric motor, characterized in that the thermistor is inserted through the through hole, among the plurality of through holes, that is located closest to a position where the drawn-out portion from the coil is drawn out;

2. the through hole has a first hole portion that functions as the thread hole or the sensor hole, and a second hole portion that functions only as the thread hole, The diameter of the first hole portion is larger than the diameter of the second hole portion, 2. The electric motor according to claim 1, wherein the first hole portion opens to the radially outer side, the second hole portion opens to the radially inner side, and the first hole portion is provided radially outer than the second hole portion.

3. 3. The electric motor according to claim 1, wherein the thermistor is fixed to the sensor hole by a resin mold.

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