Rotating Electric Machine

Abstract

The rotating electric machine (1) includes a rotor (20) and a stator coil (11) fixed to a shaft (50) supported rotatably in a housing, and a stator (10) having a coil base (12) fixed to the housing. The stator coil (11) is pressed against and fixed to the coil base (12) by a coil holding member (40) engaged with the stator coil (11) and a fixing target portion different from the coil base (12).

Description

[Technical field]

[0001] The present disclosure relates to a rotating electric machine in which a stator coil can be fixed easily and inexpensively. [Background technology]

[0002] Rotating electric machines are often equipped with coils through which electric current flows. In particular, when a stator coil is provided on the stator side, the stator coil needs to be fixed in some way so that it does not move inside the rotating electric machine. For example, Patent Document 1 proposes a method of fixing the stator coil by winding the stator coil around an iron core, sealing both sides in the axial direction, arranging multiple coils in an annular shape, and molding them with resin. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2013-537797 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional method requires a resin molding process, which increases costs, and there is also a problem that the molding resin deteriorates with an increase in the environmental temperature, reducing the fixing strength of the stator coil.

[0005] The present disclosure has been made to solve the problems described above, and provides a rotating electric machine in which the stator coil is fixed using a simple process to suppress increases in costs, and the fixing strength of the stator coil is maintained even when the environmental temperature rises, because the stator coil is mechanically fixed. [Means for solving the problem]

[0006] The rotating electric machine according to the present disclosure is rotatably supported by a housing. A rotor fixed to a shaftThe rotor includes a stator having a stator coil and a coil base fixed to a housing. The stator coil is fixed to the coil base by being pressed against it by a tensile force exerted by a coil holding member which is engaged with the stator coil and a fixing target portion different from the coil base. Effect of the Invention

[0007] The rotating electric machine according to the present disclosure includes a rotor fixed to a shaft supported rotatably by a housing, The rotor includes a stator having a stator coil and a coil base fixed to the housing. The number of rotors is greater than the number of stators, and the rotors are arranged on both sides of the stator in the magnetic gap direction where the rotors and the stators face each other. The stator coils include a first stator coil and a second stator coil different from the first stator coil. The first stator coil and the second stator coil are arranged on both sides of the coil base in the magnetic gap direction. The stator coil is different from the first stator coil and the coil base. , including the second stator coil Coil holding portion engaged with fixed target portion Material Therefore, it is pressed against the coil base and fixed therein. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic development view of a rotating electric machine according to a first embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of a stator coil. [Diagram 3] 1 is a schematic cross-sectional view of a rotating electric machine according to a first embodiment. [Figure 4] FIG. 4 is a partially enlarged view of FIG. [Diagram 5] 4 is an enlarged view of a portion where the stator coil is fixed to the coil base. FIG. [Figure 6] 5 is a schematic cross-sectional view of a stator coil having another shape according to the first embodiment. FIG. [Figure 7] FIG. 2 is a diagram showing an example of a coil base according to the first embodiment. [Figure 8] FIG. 8 is a diagram showing a stator coil disposed on the coil base of FIG. 7. [Figure 9] FIG. 4 is a diagram showing another example of the coil base in the first embodiment. [Figure 10] FIG. 10 is a diagram showing a stator coil disposed on the coil base of FIG. 9. [Figure 11] FIG. 13 is a diagram showing a case where a communication portion is provided in a coil base. [Figure 12]FIG. 12 is a diagram showing a state in which a stator coil is disposed on the coil base of FIG. 11. [Figure 13] 13A to 13C are diagrams showing another method of fixing the stator coil to the coil base. [Figure 14] FIG. 14 is a partially enlarged view of FIG. [Figure 15] FIG. 11 is a schematic development view of a rotating electric machine according to a second embodiment. [Figure 16] FIG. 11 is a schematic development view of one example of a rotating electric machine according to a second embodiment. [Figure 17] FIG. 11 is a schematic cross-sectional view of an example of a rotating electric machine according to a second embodiment. [Figure 18] FIG. 18 is a partially enlarged view of FIG. [Figure 19] 11 is a schematic cross-sectional view showing another shape of the stator coil according to the second embodiment. FIG. [Figure 20] 13A and 13B are diagrams showing an example of a method for engaging a coil holding member according to the second embodiment. [Figure 21] FIG. 11 is a diagram showing an example of a stator coil according to the second embodiment. [Figure 22] 13 is a diagram showing an example of a coil holding member according to the second embodiment. FIG. [Figure 23] 13 is a diagram showing an example of a coil holding member according to the second embodiment. FIG. [Figure 24] 13 is a diagram showing an example of the shape of a coil base according to the second embodiment. FIG. [Diagram 25] FIG. 25 is a diagram showing a stator coil fixed to the coil base of FIG. 24. [Figure 26] 26 is an enlarged view of a coil holding member engagement portion in FIG. 25. FIG. [Figure 27] FIG. 11 is a schematic development view of a rotating electric machine according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Embodiment 1 Hereinafter, a rotating electric machine according to an embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a schematic development of a rotating electric machine according to the first embodiment. In this embodiment, an axial gap type rotating electric machine in which the direction of the magnetic gap is parallel to the rotating shaft 51 will be used for the description. Note that structural components are not shown in FIG. 1. The rotating electric machine has a rotor 20 and a stator 10.

[0010] The rotor 20 has a back yoke 21 and permanent magnets 22 fixed to the back yoke 21. The back yoke 21 is made of magnetic material and is formed in a hollow disk shape. A plurality of permanent magnets 22 are used in the form of segments. The plurality of permanent magnets 22 are arranged at an equiangular pitch in the circumferential direction in the radial middle portion of the back yoke 21.

[0011] The permanent magnets 22 are formed in a sector shape. Each permanent magnet 22 is magnetized in the axial direction so that the axial end face becomes a north pole or a south pole. The permanent magnets 22 are arranged so that the north poles and south poles are alternately arranged in the circumferential direction when viewed from the axial direction. The permanent magnets 22 are not limited to segment-shaped magnets, and may be formed as a single hollow disk. In this case, the permanent magnet 22 is magnetized so that the north poles and south poles appear alternately in the circumferential direction. Also, any number of permanent magnets 22 formed with multiple poles may be used.

[0012] The stator 10 has a multi-phase stator coil 11 and a coil base 12. FIG. 2 shows an example of the multi-phase stator coil 11. One of the multiple windings is highlighted. The stator coil 11 has multiple windings for each phase, which are distributed windings that overlap each other in the circumferential direction. The stator coil 11 may be concentrated windings in which the windings do not overlap each other. The winding has a substantially fan-shaped shape and has a pair of sides 111 that are perpendicular to the rotation direction dr of the rotor 20. The pair of sides 111 are connected by an outer diameter side coil end portion 112 and an inner diameter side coil end portion 113. If the radial length of the sides 111 is approximately equal to the radial length of the permanent magnet 22 that is substantially fan-shaped, the magnetic flux generated from the permanent magnet 22 can be effectively used. The stator coil 11 is positioned and fixed on the coil base 12 that is formed in a substantially hollow disk shape. A method for fixing the stator coil 11 to the coil base 12 will be described later.

[0013] The structure of the rotating electric machine 1 of the present disclosure will be described with reference to FIG. 3. FIG. 3 is a schematic cross-sectional view of the rotating electric machine 1 of the present disclosure. The housing of the rotating electric machine 1 includes a frame 30, a bracket 31, and a bracket 32. The rotor 20 and the stator 10 are arranged to be substantially disk-shaped and to face each other in the axial direction. The rotor 20 is fixed to a shaft 50. The shaft 50 is rotatably supported by the brackets 31 and 32, which have a bearing holding portion at the center, via a bearing 52. The brackets 31 and 32 are formed in a substantially hollow disk shape from a non-magnetic material such as aluminum. The shaft 50 may be formed from a magnetic material or a non-magnetic material. The coil base 12 is fixed to the bracket 32. The coil base 12 may be fixed to a frame 30 formed in a cylindrical shape from a non-magnetic material such as aluminum.

[0014] The flow of magnetic flux in the rotating electric machine 1 according to the present disclosure will be described. The magnetic flux coming out of the permanent magnet 22 with the N pole on the magnetic gap side of the rotor 20 interlinks with the stator coil 11, passes through the coil base 12, interlinks with the stator coil 11 again, and enters the permanent magnet 22 with the S pole on the magnetic gap side of the rotor 20. The magnetic flux coming out of the permanent magnet 22 with the N pole on the back yoke 21 side passes through the back yoke 21, and enters the permanent magnet 22 with the S pole on the back yoke 21 side. The magnetic flux makes one revolution inside the rotating electric machine 1, forming a magnetic circuit. In the radial gap type, the magnetic flux flows two-dimensionally on the same plane, but the rotating electric machine 1 according to the present disclosure is different in that the magnetic flux flows three-dimensionally.

[0015] The torque generation principle of the rotating electric machine 1 of the present disclosure is similar to that of a radial gap type, and current is passed through the stator coil 11 in synchronization with the magnetic pole position of the rotor 20. When current is passed through the stator coil 11, copper loss occurs in the stator coil 11. In general, the increase in stator coil temperature due to copper loss determines the maximum value of the current passed through the stator coil 11.

[0016] The coil base 12 may be, for example, a wound core formed by concentrically winding a thin magnetic plate such as an electromagnetic steel plate, or a pressed powder core formed by pressing insulatingly coated soft magnetic iron powder. The coil base 12 may also be made of a non-magnetic material such as resin. When the coil base 12 is made of a magnetic material, the magnetic resistance of the magnetic circuit in the rotating electric machine 1 decreases, and the torque increases.

[0017] A method for fixing the stator coil 11 will be described with reference to FIG. 3, FIG. 4, and FIG. 5. FIG. 4 is a diagram showing an example of a method for engaging the coil holding member 40. FIG. 5 is a partially enlarged view of FIG. 4. The rotating electric machine 1 according to the present disclosure further includes a coil holding member 40 for fixing the stator coil 11. After the stator coil 11 is positioned and temporarily fixed on the coil base 12, the coil base 12 is fixed to the bracket 32. Then, one end of a wire-like coil holding member 40 such as a wire or a piano wire is engaged with the stator coil 11 as shown in FIG. 4. Then, the other end of the coil holding member 40 is engaged with a fixing target part different from the coil base 12, such as the frame 30 or a housing including the bracket 32, by a method such as welding. The wire-like coil holding member 40 may be a racing material or a string-like member made of resin.

[0018] At this time, as shown in Fig. 5, the coil holding member 40 is engaged with the engagement portion of the stator coil 11 such that a tensile force Ft is applied to the coil holding member 40. This tensile force Ft applies a pressing force Fc to the stator coil 11 in a direction toward the coil base 12, and the stator coil 11 is fixed to the coil base 12. In the example of Fig. 3, one end of the coil holding member 40 is engaged with the outer diameter side coil end portion 112 of the stator coil 11, and the other end is engaged with the frame 30, and the frame 30 is the fixed target portion. Moreover, one end of the coil holding member 40 is engaged with the inner diameter side coil end portion 113 of the stator coil 11, and the other end is engaged with the bracket 32, and the bracket 32 ​​is the fixed target portion.

[0019] The stator coil 11 is fixed to the coil base 12 by a pressing force Fc in a direction toward the coil base 12, so that the stator coil 11 is mechanically fixed to the coil base 12 without using an adhesive or molded resin. This eliminates the need for complex processes such as adhesive coating and molding, and can suppress increases in costs. Furthermore, when an adhesive or molded resin is used to fix the stator coil 11, the fixing strength of the stator coil 11 decreases in a high-temperature environment due to a decrease in the adhesive strength of the adhesive and thermal deterioration of the molded resin. On the other hand, in the present disclosure, the stator coil 11 is mechanically fixed to the coil base 12 using the coil holding member 40, so that the fixing strength is maintained even in a high-temperature environment.

[0020] The coil holding member 40 may be engaged with the outer diameter side coil end portion 112 of the stator coil 11 and a fixing target portion other than the coil base 12, such as the frame 30 or the bracket 32, to fix the stator coil 11 to the coil base 12. In this case, since space is secured on the inner diameter side, the diameter of the shaft 50 becomes larger and the rigidity of the shaft 50 becomes higher.

[0021] The coil holding member 40 may be engaged with the inner diameter side coil end portion 113 of the stator coil 11 and a fixing target portion other than the coil base 12, such as a bracket 32, to fix the stator coil 11 to the coil base 12. In this case, a structure for engaging the coil holding member 40 is not required on the outer diameter side, so that it is possible to prevent the outer diameter of the rotating electric machine 1 from becoming large.

[0022] A plurality of coil holding members 40 may be engaged with the stator coil 11 and a fixing target portion other than the coil base 12, such as the frame 30 or the bracket 32, at an equal angular pitch in the circumferential direction, to fix the stator coil 11 to the coil base 12. By fixing the stator coil 11 to the coil base 12 by the plurality of coil holding members 40, the force that the stator coil 11 receives from the coil holding members 40 is dispersed. This makes it possible to prevent excessive stress from being applied to some parts of the stator coil 11. It is also preferable to fix the stator coil 11 by engaging the coil holding members 40 in order on a diagonal line. This improves the accuracy of the parallelism of the opposing surface of the stator 10 with the rotor 20.

[0023] 3, the coil base 12 is fixed to the bracket 32, but may be fixed to the frame 30. Also, one end of the coil holding member 40 engaged with the outer diameter side coil end portion 112 is engaged with the frame 30 at the other end, but may be engaged with the bracket 32 ​​in the same manner as the coil holding member 40 engaged with the inner diameter side coil end portion 113 at one end. Also, in the example of FIG. 3, the coil holding member 40 is engaged with the outer diameter side coil end portion 112 and the inner diameter side coil end portion 113, but the engagement points of the coil holding member 40 with the stator coil 11 are not limited to the outer diameter side and inner diameter side coil end portions 112, 113, and may be engaged with a pair of sides 111.

[0024] Although the pressing force Fc acting on the stator coil 11 has been described as being generated by the tensile force Ft from the coil holding member 40, the pressing force Fc may also be generated by elastic deformation of either the outer diameter side or inner diameter side coil end portions 112, 113 of the stator coil 11. Also, the coil holding member 40 may have elasticity, and when the coil holding member 40 is engaged with the stator coil 11 and a fixed target portion other than the coil base 12, a tensile stress may be generated at both ends of the coil holding member 40, and the pressing force Fc may be generated by this tensile stress. Also, the pressing force Fc may be generated by a combination of the above.

[0025] 6 is a diagram showing a case where the outer diameter side and inner diameter side coil end portions 112, 113 are formed by bending them toward the coil base 12. As shown in FIG. 6, the outer diameter side and inner diameter side coil end portions 112, 113 are formed by bending them toward the coil base 12, and the coil holding member 40 is engaged with the formed portions. This makes it possible to prevent the coil holding member 40 from protruding toward the rotor 20 side beyond the magnetic gap side end face of the stator coil 11. The portions that are formed by bending them toward the coil base 12 are not limited to the outer diameter side and inner diameter side coil end portions 112, 113, and may be a pair of sides 111.

[0026] The coil holding member 40 may be made of a material with high thermal conductivity. Heat transferred from the stator coil 11 to the coil holding member 40 is transferred to the frame 30 and the bracket 32. The heat is also dissipated from the surface of the coil holding member 40. This suppresses the temperature rise of the stator coil 11.

[0027] FIG. 7 is a diagram showing an example of the coil base 12a of this embodiment. The coil base 12a is provided with a protruding rib 14 protruding in the direction of the magnetic gap on the surface facing the magnetic gap and on which the stator coil 11 is arranged. FIG. 8 is a diagram showing the stator coil 11 arranged on the coil base 12a on which the protruding rib 14 is provided. A pair of sides 111 abut against the rib 14. This determines the circumferential position of the stator coil 11. In the example of FIG. 7, the protruding rib 14 is provided so as to correspond to a pair of sides 111 perpendicular to the rotation direction dr of all the rotors 20, but it is not necessary that the protruding rib 14 corresponds to all the sides 111.

[0028] FIG. 9 is a diagram showing another example of the coil base 12b of this embodiment. The ribs 14a provided on the coil base 12b extend in a direction perpendicular to the rotation direction dr of the rotor 20. In the example of this embodiment, this corresponds to the radial direction. The ribs 14a are provided at equal angular pitches in the circumferential direction, and two adjacent ribs 14a form a slot 15. The ribs 14a are provided so that the slots 15 correspond to all the sides 111 of the stator coil perpendicular to the rotation direction dr of the rotor 20. The radial length of the ribs 14a may be approximately the same as the sides 111 of the stator coil. FIG. 10 is a diagram showing a case where the stator coil 11 is arranged on the coil base 12b of FIG. 9. In this case, the sides 111 of the stator coil 11 are inserted along the slots 15, so that the stator coil can be assembled using an automatic winding machine.

[0029] FIG. 11 is a diagram showing a case where the coil base 12c is provided with the communication portion 13. FIG. 12 is a diagram showing a case where the stator coil 11 is arranged on the coil base 12c. As shown in FIG. 11, the coil base 12c is provided with the communication portion 13, and the coil holding member 40 is engaged with the stator coil 11 and a fixing target portion different from the coil base 12c through the communication portion 13. This makes it possible to fix the stator coil 11 to the coil base 12c using the coil holding member 40 even when the outer diameter of the coil base 12c is larger than the outer diameter of the stator coil 11 or when the inner diameter of the coil base 12c is smaller than the inner diameter of the stator coil 11. In addition, since the coil base 12c can be made larger, a space for fixing to the bracket 32 ​​is secured.

[0030] FIG. 13 is a diagram showing another method of fixing the stator coil 11 to the coil base 12. FIG. 14 is a partially enlarged view of FIG. 13. One end of the coil holding member 40 is engaged with, for example, the outer diameter side coil end portion 112 of the stator coil 11. The other end of the coil holding member 40 is passed through the opposite side of the magnetic gap of the coil base 12 and engaged with the inner diameter side coil end portion 113 of the stator coil 11. In this case, the inner diameter side coil end portion 113 corresponds to the fixing target portion. As shown in FIG. 14, a tension Ft is applied to the coil holding member 40 at the engaging portion with the outer diameter side coil end portion 112 of the stator coil 11 and the abutting portion with the coil base 12. This tension Ft applies a pressing force Fc in the direction toward the coil base 12 to the stator coil 11, and the stator coil 11 is fixed to the coil base 12.

[0031] In this case, a radial slot 15 may be provided on the surface of the coil base 12 opposite to the magnetic gap. With this, by arranging the coil holding member 40 in this slot 15, the coil base 12 can be fixed to the bracket 32 ​​without the coil holding member 40 interfering with the bracket 32. According to this method of fixing the stator coil 11, the stator coil 11 can be mechanically fixed to the coil base 12 before the coil base 12 is fixed to the bracket 32, improving the reliability of the assembly process.

[0032] 13, the coil holding member 40 is engaged with the outer diameter side coil end portion 112 and the inner diameter side coil end portion 113 of the stator coil, but both ends may be engaged with the outer diameter side coil end portion 112 of the stator coil 11 as long as they do not interfere with the central portion. In this case, since there is space on the outer diameter side when attaching the coil holding member 40 to the stator coil 11, the workability of the attachment operation is improved.

[0033] <Advantages of the First Embodiment> In the rotating electric machine according to the first embodiment, the coil holding member 40 is engaged with the stator coil 11 and a fixing target portion different from the coil base 12. As a result, a pressing force Fc is generated in the stator coil 11 in a direction toward the coil base 12, and the stator coil 11 is mechanically fixed to the coil base 12.

[0034] With this configuration, the stator coil 11 is mechanically fixed to the coil base 12. This eliminates the need for processes such as resin molding and adhesives, and allows the stator coil 11 to be fixed in a simple process. Furthermore, the fixing strength of the stator coil 11 is maintained even in a high-temperature environment.

[0035] The coil holding member 40 may be engaged with only one of the outer diameter side coil end portion 112 or the inner diameter side coil end portion 113 of the stator coil 11. When the coil holding member 40 is engaged with only the outer diameter side coil end portion 112, space in the inner diameter portion can be secured. The outer diameter of the shaft 50 becomes large, and the rigidity of the shaft 50 becomes high.

[0036] When the coil holding member 40 is engaged only with the inner diameter side coil end portion 113, there is no need for a structure on the outer diameter side for engaging the coil holding member 40. This makes it possible to prevent the outer diameter of the rotating electric machine 1 from becoming large.

[0037] Also, the coil holding member 40 may be engaged with both the outer diameter side coil end portion 112 and the inner diameter side coil end portion 113 of the stator coil 11. With such a configuration, the number of fixing points by the coil holding member 40 increases, thereby increasing the fixing strength of the stator coil 11.

[0038] Also, the coil holding members 40 may be engaged at multiple locations in the circumferential direction. With this configuration, the stress acting on the stator coil 11 is dispersed. Also, by engaging the coil holding members 40 in order on a diagonal line, the accuracy of the parallelism of the magnetic gap surface of the stator coil 11 is improved.

[0039] Also, the coil holding member 40 may be formed in a wire shape. With this configuration, the stator coil 11 is mechanically fixed.

[0040] Furthermore, the portion of the stator coil 11 with which the coil holding member 40 engages may be bent in a direction toward the coil base 12. With this configuration, the coil holding member 40 does not protrude toward the magnetic gap side.

[0041] In addition, the coefficient of thermal conductivity of the coil holding member 40 is large. With this configuration, the heat of the stator coil 11 is transferred to the coil holding member 40 and dissipated from the coil holding member 40. This suppresses a rise in temperature of the stator coil 11.

[0042] Furthermore, the coil base 12a is provided with a communication portion 13, and the coil holding member 40 connects the stator coil 11 to a fixing target portion different from the coil base 12a through the communication portion 13. With this configuration, even if the coil base 12a is larger than the stator coil 11, the stator coil 11 is mechanically fixed using the coil holding member 40.

[0043] Furthermore, a plurality of protruding ribs 14 protruding in the direction of the magnetic gap are provided on the surface of the coil base 12b, which faces the magnetic gap and on which the stator coil 11 is disposed. With this configuration, the edge 111 of the stator coil 11 perpendicular to the rotation direction dr of the rotor 20 is fixed by abutting against the side surface of the rib 14. This determines the circumferential position of the stator coil 11.

[0044] Moreover, the ribs 14a are provided extending in a direction perpendicular to the rotation direction dr of the rotor 20. The multiple ribs 14a are provided corresponding to all the sides 111 of the stator coil 11 perpendicular to the rotation direction dr of the rotor 20, and slots 15 are formed between the multiple adjacent ribs 14a. The sides 111 of the stator coil 11 perpendicular to the rotation direction dr of the rotor 20 are inserted into the slots 15. With this configuration, the sides 111 of the stator coil 11 abut against the side surfaces of the ribs 14a and are fixed, thereby determining the circumferential position of the stator coil 11. Furthermore, since the stator coil 11 is assembled along the ribs 14a, assembly by an automatic winding machine is possible.

[0045] Furthermore, in the rotating electric machine according to the first embodiment, the magnetic gap direction of the rotating electric machine 1 is parallel to the rotating shaft 51 of the rotating electric machine 1. With such a configuration, the magnetic gap surface is increased in a flat structure, and the torque is increased.

[0046] Embodiment 2 The rotating electric machine 1 according to the second embodiment will be described below with reference to the drawings, focusing on differences from the rotating electric machine 1 according to the first embodiment. FIG. 15 is a schematic development view of the rotating electric machine according to the second embodiment. The rotors 20 are arranged on both sides of the stator 10 in the magnetic gap direction. The basic structures of the stator 10 and the rotor 20 are the same as those of the first embodiment. One rotor 20 is the first rotor 23, and the other rotor 20 is the second rotor 24. The first rotor 23 and the second rotor 24 are fixed to a common shaft 50 (not shown) and rotate. The circumferential phases of the permanent magnets 22 of the first rotor 23 and the second rotor 24 are equal to each other. The permanent magnets 22 of the first rotor 23 and the permanent magnets 22 of the second rotor 24, which are arranged in the same circumferential phase, are magnetized to different polarities. The sum of the torque generated in the first rotor 23 and the torque generated in the second rotor 24 is the output torque from the shaft 50. In order to reduce the time fluctuation of the output torque, the circumferential phases of the permanent magnets 22 of the first rotor 23 and the permanent magnets 22 of the second rotor 24 may be different from each other.

[0047] A magnetic circuit of a rotating electric machine according to the second embodiment will be described. The magnetic flux coming out of the permanent magnet 22 of the first rotor 23, whose magnetic gap side is magnetized to an N pole, interlinks with the stator coil 11, and enters the permanent magnet 22 of the second rotor 24, whose magnetic gap side is magnetized to an S pole. It leaves the N pole on the back yoke 21 side, passes through the back yoke 21, and enters the S pole of the adjacent permanent magnet 22. It leaves the N pole on the magnetic gap side, interlinks with the stator coil 11, and enters the permanent magnet 22 of the first rotor 23, whose magnetic gap side is magnetized to an S pole. It leaves the N pole on the back yoke 21 side, passes through the back yoke 21, and enters the S pole of the adjacent permanent magnet 22, forming a magnetic circuit.

[0048] In this embodiment, the coil base 12 faces the first rotor 23, and the stator coil 11 faces the second rotor 24. Therefore, if the coil base 12 is made of a magnetic material, the magnetic gaps on both sides have different magnetic gap lengths. The attractive forces acting between the first rotor 23 and the second rotor 24 and the stator 10 are different, and a large stress is applied to the fixed portion of the stator 10. For this reason, it is preferable that the coil base 12 is made of a non-magnetic material. When the rotating electric machine is a permanent magnet synchronous machine, the magnetic flux in the stator 10 fluctuates when the rotor 20 rotates. When the stator 10 has a magnetic material, the fluctuating magnetic flux causes iron loss in the magnetic material even when no load is applied or when operating at low output. When no load is applied or when operating at low output, the influence of the iron loss generated in the magnetic material of the stator 10 becomes large. When the coil base 12 is made of a non-magnetic material, no iron loss occurs.

[0049] FIG. 16 is a schematic development view of another example of a rotating electric machine according to the present embodiment. As shown in FIG. 16, the stator 10a has a stator coil 11a and a coil base 12. The stator coil 11a further includes a second stator coil 115 in addition to the first stator coil 114. The first stator coil 114 and the second stator coil 115 are arranged on both sides of the coil base 12 in the magnetic gap direction. The first stator coil 114 and the second stator coil 115 are wound with the same number of turns using magnet wire with the same wire diameter. The wire diameter and the number of turns of the magnet wire are not limited to be the same for the first stator coil 114 and the second stator coil 115, and may be different from each other.

[0050] The first stator coil 114 and the second stator coil 115 are connected in series. This reduces the number of turns of the first stator coil 114 and the second stator coil 115 compared to the case where the stator coil 11 is arranged only on one side of the coil base 12 in the magnetic gap direction. Generally, when the number of turns of the stator coil increases, the coil end portion is more likely to bulge. By having the stator coil 11a include the first stator coil 114 and the second stator coil 115, the expansion of the coil end portion of the stator coil 11a is suppressed, and it is possible to reduce the outer diameter of the rotating electric machine 1 and ensure the outer diameter of the shaft.

[0051] The first stator coil 114 and the second stator coil 115 may be connected in parallel. In this case, a magnet wire with a thinner wire diameter can be used to achieve the same resistance value as when the stator coil 11 is arranged on only one side of the coil base 12 in the magnetic gap direction. By using a magnet wire with a thinner wire diameter, winding swelling at the coil end portion is suppressed. When a magnet wire with the same wire diameter is used, the winding resistance is smaller and copper loss due to current flow is reduced.

[0052] The first stator coil 114 and the second stator coil 115 are disposed on either side of the coil base 12 in the magnetic gap direction. This increases the contact area between the stator coil 11 and the coil base 12. This reduces the thermal resistance between the stator coil 11 and the coil base 12, making it easier for heat to be transferred from the stator coil 11 to the coil base 12. This suppresses the temperature rise of the stator coil 11.

[0053] FIG. 17 is a diagram showing an example of an engagement method of the coil holding member 40 according to the present embodiment. When the first stator coil 114 and the second stator coil 115 are arranged on both sides of the coil base 12 in the magnetic gap direction, the coil holding member 40 is engaged with the first stator coil 114 and the second stator coil 115 as shown in FIG. 17. The first stator coil is an example of a stator coil in the claims, and the second stator coil is an example of a fixed target part in the claims. FIG. 18 is an enlarged view of an engagement part of the coil holding member 40 in FIG. 17. As shown in FIG. 18, a tensile force Ft acts between the part of the coil holding member 40 engaged with the first stator coil 114 and the part of the coil holding member 40 engaged with the second stator coil 115. This tensile force Ft causes a pressing force Fc in a direction toward the coil base 12 to act on the first stator coil 114 and the second stator coil 115. The pressing force Fc fixes the first stator coil 114 and the second stator coil 115 to the coil base 12. As a result, the stator coil 11a is mechanically fixed to the coil base 12, and then the coil base 12 is fixed to the frame 30 or the bracket 32, improving the workability of the assembly process of the coil base 12.

[0054] When the coil holding member 40 is engaged with the first stator coil 114 and the second stator coil 115, the first stator coil 114 and the second stator coil 115 may be elastically deformed. As a result, an elastic force acts on the first stator coil 114 and the second stator coil 115. This elastic force may generate a pressing force Fc acting on the first stator coil 114 and the second stator coil 115. The pressing force Fc may be generated by both the tensile force Ft and the elastic force.

[0055] FIG. 19 is a schematic cross-sectional view of another example of the rotating electric machine according to the present embodiment. The stator 10b has a stator coil 11b having a first stator coil 114a and a second stator coil 115a, and a coil base 12. The first stator coil 114a and the second stator coil 115a are each formed by bending toward the coil base 12. The coil holding member 40 is engaged with the first stator coil 114a and the second stator coil 115a at the positions where the coils are bent. As a result, the first stator coil 114a and the second stator coil 115a are fixed to the coil base 12. Since the coil holding member 40 is engaged with the positions where the first stator coil 114a and the second stator coil 115a are formed by bending toward the coil base 12, the coil holding member 40 does not protrude toward the magnetic gap. In FIG. 19 , the portions that are bent toward the coil base 12 are the outer diameter side and inner diameter side coil end portions, but the portions that are bent are not limited to the outer diameter side and inner diameter side coil end portions 112, 113.

[0056] 20 is a diagram showing an example of a method for engaging the coil holding member 40 according to this embodiment. The coil holding member 40 is formed of a wire-like member. One end of the coil holding member 40 is engaged with the first stator coil 114, and is hooked alternately at multiple points on the second stator coil 115 and the first stator coil 114. The other end of the coil holding member 40 is engaged with the first stator coil 114 or the second stator coil 115. In the example of FIG. 20, the other end of the coil holding member 40 is engaged with the first stator coil 114, but it may also be engaged with the second stator coil 115.

[0057] A tensile force Ft acts on the coil holding member 40 at an engagement portion with the first stator coil 114 and at a subsequent engagement portion with the second stator coil 115. A pressing force Fc in a direction toward the coil base 12 acts on the first stator coil 114 and the second stator coil 115 due to the tensile force Ft. The first stator coil 114 and the second stator coil 115 are fixed to the coil base 12 by the pressing force Fc. Since the coil holding member 40 is engaged with a plurality of points of the first stator coil 114 and the second stator coil 115, the stress acting on the first stator coil 114 and the second stator coil 115 is reduced.

[0058] In this engagement method, the pressing force Fc may be generated by an elastic force acting on the first stator coil 114 and the second stator coil 115, or may be generated by a tensile stress acting on the engagement portions at both ends of the coil holding member 40. Also, the pressing force Fc may be generated by a combination of the above.

[0059] Fig. 21 is a diagram showing an example of a stator coil 11c according to this embodiment. When the coil holding member 40 is engaged with the outer diameter side coil end portion 112 of the stator coil 11c as in Fig. 21, a coil protrusion 116 protruding outwardly may be provided at the location where the coil holding member 40 is engaged. By providing the coil protrusion 116, it becomes possible to operate the attachment jig for the coil holding member 40 without interfering with the surrounding outer diameter side coil end portion 112.

[0060] 22 and 23 are diagrams showing an example of the coil holding member 40 according to the present embodiment. In both cases of FIG. 22 and FIG. 23, the coil holding members 40a and 40b are formed to have a pair of curved portions at both ends. In the example of FIG. 22, the coil holding member 40a is formed in a substantially C-shape, and in the example of FIG. 23, the coil holding member 40b is formed in a substantially S-shape. The coil holding members 40a and 40b have elasticity. One curved portion of the coil holding members 40a and 40b is engaged with the first stator coil 114, and the other curved portion is engaged with the second stator coil 115. An elastic force acts on both ends of the coil holding members 40a and 40b. This elastic force exerts a pressing force in a direction toward the coil base 12 on each of the first stator coil 114 and the second stator coil 115. As a result, the first stator coil 114 and the second stator coil 115 are each fixed to the coil base 12. By using the coil holding member 40 formed from an elastic body and having a pair of curved portions in this manner, the stator coil 11 is mechanically fixed to the coil base 12 in a simple manner.

[0061] The coil holding members 40a, 40b may not have elasticity. In this case, one curved portion of the coil holding members 40a, 40b is engaged with the first stator coil 114, and the other curved portion is engaged with the second stator coil 115, so that the first stator coil 114 and the second stator coil 115 are elastically deformed toward the coil base 12. An elastic force acts on the first stator coil 114 and the second stator coil 115, and this elastic force applies a pressing force to the first stator coil 114 and the second stator coil 115 in the direction of the coil base 12. As a result, the first stator coil 114 and the second stator coil 115 are fixed to the coil base 12. The pressing force acting on the first stator coil 114 and the second stator coil 115 may be generated by both the coil holding members 40 a and 40 b and the elastic force acting on the first stator coil 114 and the second stator coil 115 .

[0062] FIG. 24 is a diagram showing an example of the shape of the coil base 12d according to this embodiment. A plurality of ribs 14a are provided on both sides of the coil base 12d in the magnetic gap direction, each protruding in the magnetic gap direction. The plurality of ribs 14a extend in a direction perpendicular to the rotation direction dr of the rotor 20. Adjacent ribs of the plurality of ribs 14a form a slot 15. The plurality of ribs 14a are provided corresponding to all sides 111 of the stator coil 11 perpendicular to the rotation direction dr of the rotor 20. In addition, the plurality of ribs 14a provided on the coil base 12d may be provided at corresponding positions on one surface and the other surface, and the circumferential positions of the ribs 14a on both sides of the magnetic gap direction may be shifted. FIG. 25 is a diagram showing the arrangement of a first stator coil 114 and a second stator coil 115 on the coil base 12d of FIG. 24. Since the circumferential positions of the ribs provided on both sides of the coil base 12d in the magnetic gap direction are shifted, the circumferential positions of the first stator coil 114 and the second stator coil 115 are also different. FIG. 26 shows an enlarged view of the engagement portion of the coil holding member 40. When the coil holding member 40 is engaged with each of the first stator coil 114 and the second stator coil 115, the tensile force Ft acting on the coil holding member 40 has an axial component and a circumferential component. Since the tensile force Ft includes a circumferential component, a circumferential force Fd acts on the first stator coil 114 and the second stator coil 115 in addition to a pressing force Fc in a direction toward the coil base 12d. Due to the circumferential force Fd, the first stator coil 114 and the second stator coil 115 abut against the side surface of the rib 14a and are fixed in the circumferential direction. The rib 14 may be a protrusion as shown in the first embodiment. Furthermore, the multiple ribs 14a do not necessarily have to correspond to all the sides 111 of the stator coil 11 that are perpendicular to the rotation direction dr of the rotor 20.

[0063] As in the first embodiment, the coil base 12 may be provided with a communication portion 13. The coil holding member 40 is engaged with a fixing target portion different from the stator coil 11 and the coil base 12 through the communication portion 13. When the stator coil 11a has a first stator coil 114 and a second stator coil 115, the coil holding member 40 is engaged with the first stator coil 114 and the second stator coil 115. Even when the outer diameter of the coil base 12 is larger than the outer diameter of the stator coil 11a, or when the inner diameter of the coil base 12 is smaller than the inner diameter of the stator coil 11, the stator coil 11 can be fixed to the coil base 12 using the coil holding member 40. In addition, since the coil base 12 can be made larger, a space for fixing the coil base 12 to the housing of the rotating electric machine 1 is secured.

[0064] <Advantages of the second embodiment> In the rotating electric machine 1 of this embodiment as well, the coil holding member 40 is engaged with the stator coil 11 and a fixing target portion different from the coil base 12. This generates a pressing force Fc on the stator coil 11 in a direction toward the coil base 12, and the stator coil 11 is mechanically fixed to the coil base 12.

[0065] In the rotating electric machine 1 of the present embodiment, the number of rotors 20 is greater than the number of stators 10, and the rotors 20 are disposed on both sides of the stators 10 in the magnetic gap direction. With this configuration, the magnetic gap surface is increased, and the torque is increased.

[0066] The stator coil 11a has a first stator coil 114 and a second stator coil 115, which are respectively arranged on both sides of the coil base 12 in the magnetic gap direction. A coil holding member 40 is engaged with the first stator coil 114 and the second stator coil 115, and the first stator coil 114 and the second stator coil 115 are respectively fixed to the coil base 12. Since the coil base 12 is fixed to the frame 30 or the bracket 32 ​​with the first stator coil 114 and the second stator coil 115 in a fixed state, the workability of the assembly process is improved.

[0067] The first stator coil 114 and the second stator coil 115 are connected in series. This reduces the number of turns in the first stator coil 114 and the second stator coil 115 compared to when the stator coil 11 is arranged only on one side of the coil base 12 in the magnetic gap direction. If the number of turns increases, the winding bulge of the coil end portion increases. This configuration prevents the external dimensions of the rotating electric machine 1 from becoming larger.

[0068] The first stator coil 114 and the second stator coil 115 are connected in parallel. In this case, if a wire magnet with the same wire diameter as that in the case where the stator coil 11 is arranged only on one side of the coil base 12 in the magnetic gap direction is used, the winding resistance is reduced. If the amount of current flowing through the stator coil 11a is the same as that in the case where the stator coil 11 is arranged only on one side of the coil base 12 in the magnetic gap direction, the copper loss generated in the stator coil 11a is reduced. Under the condition that the copper loss generated in the stator coil 11a is the same as that in the case where the stator coil 11 is arranged on one side of the coil base 12, more current can be passed, so that the torque increases. To make the winding resistance the same as that in the case where the stator coil 11 is arranged only on one side of the coil base 12 in the magnetic gap direction, the wire diameter of the magnet wire used is made thinner. By making the wire diameter of the magnet wire thinner, the winding bulge of the coil end portion is reduced, and the external size of the rotating electric machine 1 is prevented from becoming larger.

[0069] Furthermore, the contact area between the stator coil 11a and the coil base 12 increases, reducing the thermal resistance between the stator coil 11a and the coil base 12. This allows the heat of the stator coil 11a to be transferred to the coil base 12, suppressing a temperature rise in the stator coil 11a. Alternatively, if the temperature rise is the same as when the stator coil 11 is disposed on only one side of the coil base 12 in the magnetic gap direction, more current can be passed and the torque increases.

[0070] One end of the coil holding member 40 formed of a wire-like member is engaged with the first stator coil 114, and then the end is hooked alternately at multiple points on the second stator coil 115 and the first stator coil 114. The other end of the coil holding member 40 is engaged with the first stator coil 114 or the second stator coil 115, and the first stator coil 114 and the second stator coil 115 are fixed to the coil base 12. With this configuration, the stress acting on the first stator coil 114 and the second stator coil 115 is dispersed.

[0071] The coil holding members 40a, 40b are formed to have a pair of curved portions. The curved portions of the coil holding member 40 are engaged with the first stator coil 114 and the second stator coil 115, respectively, and the first stator coil 114 and the second stator coil 115 are fixed to the coil base 12. With this configuration, the stator coil 11 is fixed to the coil base 12 in a simple process.

[0072] Ribs 14 are provided on the surface of the coil base 12 on which the stator coil 11a is arranged so as to protrude in the direction of the magnetic gap, and the circumferential phase of the ribs 14 differs on both sides of the magnetic gap direction. When the first stator coil 114 and the second stator coil 115 are fixed by the coil holding member 40, a pressing force Fc in a direction toward the coil base 12 and a circumferential force Fd act on the first stator coil 114 and the second stator coil 115. The circumferential force Fd causes the first stator coil 114 and the second stator coil 115 to come into contact with the side surfaces of the ribs 14 and to be positioned in the circumferential direction.

[0073] In the first embodiment, the rotating electric machine 1 has one stator 10 and one rotor 20, and in the second embodiment, it has one stator 10 and two rotors 20, but it may be an axial gap type rotating electric machine with two or more stators 10 and three or more rotors 20 as shown in Fig. 27. In this case, the torque increases because the magnetic gap surface that becomes the torque generating surface increases.

[0074] In the first and second embodiments, an axial gap type rotating electric machine has been described as an example, but the rotating electric machine may be a radial gap type rotating electric machine in which the direction of the magnetic gap is perpendicular to the rotation axis 51 of the rotor 20. [Explanation of symbols]

[0075] 1 rotating electric machine, 10, 10a, 10b stator, 11, 11a, 11b stator coil, 111: portion perpendicular to the direction of rotation; 112: outer diameter side coil end portion; 113 Inner diameter side coil end portion, 114, 114a, 114b first stator coil, 115, 115a, 115b second stator coil, 116 coil protrusion 12, 12a, 12b, 12c, 12d coil base, 13 communicating portion, 14, 14a rib, 15 slot 20 rotor, 21 back yoke, 22 permanent magnet, 23 first rotor, 24 second rotor, 30 Frame, 31, 32 Bracket 40, 40a, 40b coil holding member, 50 shaft, 51 rotating shaft, 52 Bearing dr Rotational direction, Ft Tensile force, Fc Pressing force, Fd Circumferential force

Claims

1. A rotor fixed to a shaft rotatably supported in a housing; a stator having a stator coil and a coil base fixed to the housing; Equipped with The stator coil is pressed and fixed to the coil base by a tensile force of a coil holding member engaged with the stator coil and a fixing target portion different from the coil base. A rotating electric machine characterized by:

2. A rotor fixed to a shaft rotatably supported in a housing; a stator having a stator coil and a coil base fixed to the housing; Equipped with The stator coil is elastically deformed by a coil holding member engaged with the stator coil and a fixing target portion different from the coil base, and is pressed against the coil base by an elastic force generated by the elastic deformation and fixed. A rotating electric machine characterized by:

3. The number of the rotors is greater than the number of the stators, and the rotors are arranged on both sides of the stator in the magnetic gap direction in which the rotors and the stators face each other.

3. The rotating electric machine according to claim 1 or 2.

4. The fixing target portion includes the housing.

3. The rotating electric machine according to claim 1, wherein the first and second electrodes are electrically connected to each other.

5. A rotor fixed to a shaft rotatably supported in a housing; a stator having a stator coil and a coil base fixed to the housing; Equipped with the number of the rotors is greater than the number of the stators, and the rotors are disposed on both sides of the stator in a magnetic gap direction in which the rotors and the stators face each other; the stator coil includes a first stator coil and a second stator coil different from the first stator coil, the first stator coil and the second stator coil are disposed on both sides of the coil base in the magnetic gap direction, The stator coil is pressed against and fixed to the coil base by a coil holding member engaged with the stator coil and a fixing target portion different from the coil base.

3. The rotating electric machine according to claim 2, wherein the rotating electric machine comprises:

6. The fixed target portion includes the second stator coil.

6. The rotating electrical machine according to claim 5.

7. The coil holding members are attached alternately to the first stator coil and the second stator coil and at a plurality of locations on the first stator coil and the second stator coil.

7. The rotating electrical machine according to claim 6.

8. The portion of the stator coil where the coil holding member is attached is bent in a direction toward the coil base.

6. The rotating electric machine according to claim 1, 2 or 5.

9. A communication portion is provided in the coil base, and the coil holding member passes through the communication portion.

6. The rotating electric machine according to claim 1, 2 or 5.

10. A surface of the coil base on which the stator coil is disposed is provided with a plurality of ribs that protrude toward the rotor.

3. The rotating electric machine according to claim 1 or 2.

11. The plurality of ribs are provided to correspond to all sides of the stator coil that are perpendicular to the rotation direction of the rotor, and extend in a direction perpendicular to the rotation direction of the rotor. Adjacent ribs of the plurality of ribs form slots, and the sides of the stator coil that are perpendicular to the rotation direction of the rotor are inserted into the slots.

11. The rotating electric machine according to claim 10.

12. A surface of the coil base on which the stator coil is disposed is provided with a plurality of ribs that protrude toward the rotor.

6. The rotating electric machine according to claim 1, 2 or 5.

13. The plurality of ribs are provided to correspond to all sides of the stator coil that are perpendicular to the rotation direction of the rotor, and extend in a direction perpendicular to the rotation direction of the rotor. Adjacent ribs of the plurality of ribs form slots, and the sides of the stator coil that are perpendicular to the rotation direction of the rotor are inserted into the slots.

13. The rotating electric machine according to claim 12.

14. a plurality of ribs protruding toward the rotor are provided on a surface of the coil base on which the stator coil is disposed; The plurality of ribs are provided on both sides of the coil base in the magnetic gap direction so that one surface of the coil base corresponds to the other surface of the coil base, and the circumferential positions of the plurality of ribs provided on both sides of the coil base are different on both sides in the magnetic gap direction.

13. The rotating electric machine according to claim 5 or 12.

15. The coil holding member is attached to only one of the inner diameter side coil end portion and the outer diameter side coil end portion of the stator coil.

6. The rotating electric machine according to claim 1, 2 or 5.

16. The coil holding member is attached to both the inner diameter side coil end portion and the outer diameter side coil end portion of the stator coil.

6. The rotating electric machine according to claim 1, 2 or 5.

17. The coil holding members are attached to the stator coil at a plurality of locations in the circumferential direction.

6. The rotating electric machine according to claim 1, 2 or 5.

18. The coil holding member has a pair of curved portions.

7. The rotating electrical machine according to claim 6.

19. The coil holding member is wire-shaped.

6. The rotating electric machine according to claim 1, 2 or 5.

20. The coil holding member is formed of an elastic body.

6. The rotating electric machine according to claim 1, 2 or 5.

21. The coil holding member is made of a material with a high thermal conductivity.

6. The rotating electric machine according to claim 1, 2 or 5.

22. The direction in which the rotor and the stator face each other is parallel to the rotation axis of the rotor.

6. The rotating electric machine according to claim 1, 2 or 5.

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