JP3864629B2 - motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique for improving a motor such as a switched reluctance motor (SR motor).
[0002]
[Prior art]
An SR motor is known as one of conventional motors. In the SR motor, a stator (stator) formed by integrally forming a plurality of inwardly projecting salient poles on a cylindrical yoke and a rotor (rotor) having a plurality of outwardly projecting salient poles are coaxial. It is arranged on the top and mounted with winding coils on the salient poles of the stator. The stator is fixed inside the motor housing, the rotation shaft of the rotor is rotatably supported by the end cap via a bearing, and the end cap is fixed to the motor housing.
[0003]
The number of the salient poles of the rotor and the salient poles of the stator is set to an even number that is not in a multiple relationship with each other. For example, the number of salient poles of the rotor is 4, the number of salient poles of the stator is 6, the number of salient poles of the rotor is 6, the number of salient poles of the stator is 8, and the number of salient poles of the rotor is 8. On the other hand, the number of salient poles of the stator is 12.
[0004]
A current is passed through a pair of opposed winding coils of the stator (in some cases, a plurality of winding coils) to generate a magnetic flux from the stator salient poles to the rotor salient poles. Torque is generated by attracting to. At this time, if the salient poles of the stator and the rotor face each other, the other salient poles are displaced from each other, and if the sequentially shifted salient poles are selected and the winding coils are energized, the rotor salient poles become continuous. The rotor can be rotated about its axis. Such an SR motor can also function as a generator.
[0005]
In the present specification, the “motor” includes not only an electric motor that generates motive power (a motor in a narrow sense) but also a generator that generates electric power, or a generator motor that has both functions.
[0006]
By the way, the winding coil is configured by winding a coil wire around a bobbin formed in an annular shape with a U-shaped cross section, for example. The through hole in the center of the bobbin has a shape that can be inserted into the salient pole of the stator. By inserting the salient pole of the stator into the through hole of the bobbin, the winding coil is attached to the salient pole of the stator. . After the winding coil is inserted into the salient pole of the stator, it is fixed by inserting plate-like bars into the portions between the side portions of the adjacent salient poles of the stator that protrude from the bobbin. It is designed to prevent slipping out of the camera.
[0007]
[Problems to be solved by the invention]
However, as described above, to fix the winding coil (bobbin) to the salient pole of the stator, it is necessary to insert a dedicated member called a bar used only for fixing the winding coil between the salient poles. , It takes a long time to assemble and requires a long time to assemble, and the bar itself is fixed by being sandwiched between the salient poles, so the angle between the salient poles is small especially in motors with many salient poles, There was a problem that the bar could fall out and the fixing reliability was low.
[0008]
Further, for example, as shown in FIG. 4B, most of the magnetic flux generated by energizing the winding coil passes through the salient poles of the stator 3 and the rotor 2 having a small magnetic resistance. In the vicinity of the end face in the axial direction of the rotor 2, the salient pole of the stator 3 comes out of the end face in the axial direction and then enters the salient pole of the rotor 2 from the end face in the axial direction of the salient pole of the rotor 2. The magnetic flux B that does not go to the magnetic flux B and the salient pole of the rotor 2 but turns around the winding coil 7 is generated.
[0009]
Therefore, in the vicinity of the axial end faces of the rotor and the stator, a magnetic flux is generated that pulls the rotor in the axial direction, and a magnetic flux that does not generate torque that does not contribute to the torque is generated. There was a problem of lowering the output. This phenomenon is particularly noticeable in SR motors that are used at a saturation magnetic flux density or higher. Especially in the case of a thin motor, the ratio of the magnetic flux that does not contribute to the magnetic flux that contributes to the generation of rotational torque increases. The decline is remarkable.
[0010]
The present invention has been made in view of the above-described problems of the prior art, and it is an object of the present invention to facilitate assembling work of a motor and improve reliability. Moreover, it aims at improving the output of a motor.
[0011]
[Means for Solving the Problems]
(1) In order to achieve the above object, a motor according to a first aspect of the present invention includes a stator having a plurality of salient poles projecting inward and windings provided so as to surround the salient poles of the stator. In a motor comprising a wire coil and a rotor provided inside the stator having a plurality of salient poles projecting outward, a protrusion that abuts the winding coil from the inside and fixes the winding coil An end cap formed integrally is provided, and the tip of the projection is in contact with only the end surface in the axial direction of the salient pole of the stator.
[0012]
According to the motor of the first aspect of the present invention, the winding coil is fixed to the salient pole of the stator by the contact of the protrusions of the end cap. The wire coil can be fixed, and the operation becomes extremely simple as compared with the conventional case where the bars are individually mounted. Further, since the protruding portion is formed integrally with the end cap, it does not fall out like a conventional bar and has high reliability. In addition, heat generated by the winding coil and salient poles is transferred to the main body of the end cap (the part excluding the protrusions) via the protrusions, and can be dissipated from the end cap. can do. In particular, in the present invention, the tip of the protrusion is brought into contact with the end face of the salient pole of the stator, so that the area of the portion shielded by the protrusion is increased, so that the magnetic flux shielding effect becomes higher and torque is generated. The magnetic flux that effectively contributes to the magnetic field can be further increased, and since the protrusion is in direct contact with the salient pole of the stator, the heat generated by the eddy current in the salient pole can be radiated more efficiently. it can.
[0013]
Here, as the winding coil, for example, a coil wire wound around a ring-shaped bobbin having a U-shaped cross section, a coil wire wound and tied with a string or the like to hold the shape or resin, etc. And those obtained by winding the coil wire directly around the salient poles of the stator.
[0014]
(2) In order to achieve the above object, a motor according to a second aspect of the present invention is the motor according to the first aspect, wherein the end cap is made of a nonmagnetic and conductive material.
[0015]
According to the motor of claim 2, the end cap including the protrusion is made of a nonmagnetic and conductive material (nonmagnetic conductive material), and particularly the protrusion of the end cap that is in contact with the inside of the winding coil. When a part of the magnetic flux generated by energizing the winding coil enters the part, an eddy current is generated in the protrusion, and this eddy current flows in a direction that hinders the change of the magnetic flux. Shielded by. Therefore, by reducing the magnetic flux that pulls the rotor that does not contribute effectively to the generation of torque or the magnetic flux that circulates around the coil, the salient poles of the rotor that can contribute to the generation of torque are reduced around the axis. The pulling magnetic flux can be increased.
[0016]
(3) As in the third aspect, in the motor according to the first or second aspect, the protrusion can be formed in a cylindrical shape having a central axis substantially coaxial with the rotation axis of the rotor. By making the projection part into such a cylindrical shape, it is possible to fix all the winding coils with a single projection part without worrying about the orientation of the end cap in the rotational direction, making assembly work easy. Can be However, the protrusions may be formed only at the portions corresponding to the respective winding coils, and in this case, the end cap can be reduced in weight.
[0017]
(4) As in the fourth aspect, in the motor according to the first, second, or third aspect, each portion of the protrusion that contacts the winding coil is shaped to follow the winding coil. be able to. By doing so, the area of the portion in contact with the winding coil is increased, so that more stable fixing can be realized and heat generated in the winding coil can be efficiently radiated. .
[0019]
(5) As described in claim 5, in the motor according to any one of claims 1 to 4 , the protrusion has a protrusion inserted in a portion between adjacent salient poles of the stator. Can do. By setting it as such a structure, the magnetic flux shielding property and heat dissipation in the part corresponding to the side part of the salient pole of the stator of a winding coil can be made still higher.
[0020]
(6) As in the sixth aspect, in the motor according to any one of the first to fifth aspects, the inner diameter of the protrusion is set to be substantially equal to the inner diameter of the tip of the salient pole of the stator. Can do. By doing so, the thickness of the protrusion can be maximized without causing any trouble in the rotation of the rotor, and the tip of the end face of the salient pole (the part protruding from the winding coil) is almost It becomes possible to cover completely, and magnetic flux shielding and heat dissipation can be made extremely high.
[0021]
【The invention's effect】
(1) According to the first aspect of the present invention, the work for fixing the winding coil is facilitated and the reliability of the fixing can be improved. Moreover, heat dissipation can also be improved. In addition to this, the output can be further increased and the heat dissipation can be further improved.
[0022]
(2) According to the second aspect of the present invention, in addition to the effect of the first aspect, the magnetic flux that effectively contributes to the generation of torque can be increased, and the output of the motor can be improved. . In addition, when making the output of a motor constant, a motor can be reduced in size.
[0023]
(3) According to the third aspect of the present invention, in addition to the effects of the first and second aspects, the winding coil can be fixed more easily.
[0024]
(4) According to the fourth aspect of the present invention, in addition to the effects of the first to third aspects, the winding coil can be more stably fixed and the heat dissipation can be further improved. it can.
[0026]
(5) According to this invention of Claim 5 , in addition to the said effect about Claims 1-4 , while being able to make an output larger further, heat dissipation can be improved more.
[0027]
(6) According to the present invention described in claim 6, in addition to the effects of claims 1 to 5, with the can be further increased output, it is possible to further improve heat dissipation.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0029]
1st Embodiment FIG. 1 is a plan view, partly in section, showing the main part of a first embodiment of an SR motor (switched reluctance motor) according to the present invention, and FIG. 2 is a plan view of FIG. FIG. 3 is a perspective view showing the configuration of the end cap of FIG. 1. The SR motor 1 of the first embodiment is a three-phase SR motor in which the number of stator salient poles is 6 and the number of rotor salient poles is 4.
[0030]
The SR motor 1 includes a rotor 2 as a rotor and a stator 3 as a stator. The rotor 2 is configured by inserting an output shaft (shaft) 5 into a through hole formed at the center of a rotor core 4 having a plurality of (four in this embodiment) salient poles 2a and fixing them integrally. In this embodiment, the rotor core 4 is configured by laminating and integrating a plurality of magnetic steel plates 4a punched by a press device.
[0031]
The stator 3 includes a stator core 6 and a plurality of winding coils 7. The stator core 6 is configured by integrally providing a plurality (six in this embodiment) of salient poles 3a protruding radially inward of a substantially cylindrical yoke portion. In this embodiment, the stator core 6 is configured by laminating and integrating a plurality of magnetic steel plates 6a punched by a press device.
[0032]
A winding coil 7 formed by winding a coil wire around a bobbin 8 is mounted on each salient pole 3 a of the stator 3. The bobbin 8 is a member having a U-shaped cross section and is formed in a rectangular ring shape, and is formed of an insulating material such as a resin. A coil wire is wound around a portion between both side walls of the bobbin 8, and the salient pole 3a of the stator 3 is inserted or press-fitted into a rectangular hole at the center thereof to be attached to the salient pole 3a. .
[0033]
The stator 3 is fixed inside a substantially cylindrical housing 9, the output shaft 5 of the rotor 2 is rotatably supported by a pair of end caps 10, and the end cap 10 is integrally attached to the housing 9 with screws or the like. Yes. As a result, the rotor 2 is coaxially disposed with a predetermined gap between the rotor 3 and the salient pole 3a of the stator 3.
[0034]
The end cap 10 is a substantially disk-shaped member having a cap body 10b having an outer cylindrical portion 10a and a protruding portion 12, and a through hole for allowing the output shaft 5 to pass through is formed at the center. The output shaft 5 is rotatably supported by a bearing 11 attached to the inner portion of the through hole.
[0035]
The protrusion 12 of the end cap 10 is a cylindrical protrusion integrally formed on the inner surface of the cap body 10 b so as to protrude in a direction along the output shaft 5. The end cap 10 is also a magnetic flux shielding member in which the protrusion 12 is made of a nonmagnetic and conductive material. In this embodiment, the end cap 10 is made of aluminum. As the end cap 10, copper or the like, which is another nonmagnetic conductive material, can be used. The end cap 10 may be formed from a metal or resin, and may be formed by depositing a nonmagnetic conductive material such as aluminum or copper on the protrusion 12 by vapor deposition, plating, or another film forming method. .
[0036]
The end cap 10 is inserted or press-fitted so that the protrusion 12 abuts on the inner surface (surface on the shaft 5 side) of the inner wall portion of the bobbin 8 of each winding coil 7 inserted and disposed in the salient pole 3 a of the stator 3. On the other hand, the outer cylindrical portion 10a is integrally fixed to the housing 9 with a screw or the like in a state where the front end surface is in contact with the housing 9. The winding coil 7 inserted and disposed on the salient pole 3a of the stator 3 is sandwiched between the yoke 12 of the stator 3 by the protrusion 12 of the end cap 10 being in contact with or pressed from the inside. It is fixed in a state and is prevented from coming out from the salient pole 3a.
[0037]
As described above, since the projecting portion 12 is integrally provided on the end cap 10, the end cap 10 is attached to the housing 9, and at the same time, the winding coils 7 are fixed to the salient poles 3a. Is very simple.
[0038]
Thus, a current is passed through the pair of winding coils 7 facing each other to generate a magnetic flux from the salient pole 3a of the stator 3 toward the salient pole 2a of the rotor 2, and the salient pole 2a of the rotor 2 existing in the vicinity thereof is generated. Torque is generated by attracting. When the salient poles 2a, 3a of the stator 3 and the rotor 2 are opposed to each other, the other salient poles 2a, 3a are shifted from each other. The salient poles 2a of the rotor 2 are continuously attracted so that the rotor 2 can be rotated about its axis.
[0039]
Part of the magnetic flux generated by energizing the winding coil 7 passes through the protrusion 12 of the end cap 10. Since the protrusion 12 is made of a nonmagnetic conductive material, an eddy current is generated inside the protrusion 12 in accordance with a change in the magnetic flux passing through the protrusion 12, and the eddy current is caused by a change in the magnetic flux. Since the protrusion 12 is present, the magnetic flux B flows outward from the end face of the salient pole 3a of the stator 3 as shown by an arrow in FIG. ), And is guided to the salient pole 2a side of the rotor 2.
[0040]
Thereby, the magnetic flux which contributes effectively to generation | occurrence | production of rotational torque can be increased, and the output of SR motor 1 can be improved. In particular, the increase in torque becomes significant in a high rotation range where the magnetic flux change is significant.
[0041]
Here, for comparison, FIG. 4B shows a case where the projecting portion 12 is not provided on the end cap 10. If there is no projection 12, it protrudes outward from the end face of the salient pole 3 a of the stator 3 in the vicinity of the end face in the axial direction of the stator 3 and the rotor 2, and then enters from the end face of the salient pole 2 a of the rotor 2. The magnetic flux B that travels along the path and the magnetic flux B that passes through the outside of the winding coil 7 and does not pass through the interior of the stator 3 without passing through the inside of the stator 3 are generated, and that much does not contribute to the generation of torque. Magnetic flux was generated. On the other hand, in this 1st Embodiment, this point is improved and it understands that the magnetic flux which contributes to generation | occurrence | production of a torque can be increased.
[0042]
Further, the heat generated by energizing the winding coil 7 is transmitted to the protrusion 12 through the wall portion of the bobbin 8 and is radiated to the outside through the end cap 10, thereby suppressing an increase in internal temperature. Thus, fluctuations in characteristics caused by heat generation, a decrease in continuous rated operating point, and the like can be prevented, and the reliability of the motor can be improved.
[0043]
Further, since the protruding portion 12 of the end cap 10 is cylindrical, when the end cap 10 is assembled, there is no need to consider the posture of the end cap 10 in the rotational direction around the shaft 5, and the assembling work is easy. .
[0044]
Second Embodiment FIG. 5 is a plan view in which a part of the second embodiment of the SR motor according to the present invention is shown in section, FIG. 6 is an enlarged cross-sectional view of the main part of FIG. FIG. 7 is a perspective view of the end cap of FIG. Components that are substantially the same as those of the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.
[0045]
That is, in the first embodiment described above, the protrusion 12 of the end cap 10 is a cylindrical protrusion, and thus the protrusion 12 and the bobbin 8 (winding coil 7) are so-called line contact. The contact area is small. On the other hand, the protrusion 13 of the end cap 10 of the second embodiment is in contact with the inner surface (surface on the shaft 5 side) of the inner wall of the bobbin 8 of the winding coil 7. The difference is that a flat portion 13 a is formed corresponding to the winding coil 7.
[0046]
By forming such a flat portion 13a on the protruding portion 13 of the end cap 10, the contact area with the bobbin 8 can be expanded, and the winding coil 7 can be stably held and fixed. The heat transfer efficiency of the heat generated in 7 to the end cap 10 is improved, so that the heat dissipation is further improved.
[0047]
Further, the tip of the projection 12 of the end cap 10 of the first embodiment described above does not reach the salient pole 3a of the stator 3, but the tip 13 of the projection 13 of the end cap 10 of the second embodiment has the tip thereof. The difference is that it is formed so as to be in contact with the axial end surface of the tip of the salient pole 3a of the stator 3.
[0048]
In this way, by causing the tip surface of the protrusion 13 to contact the salient pole 3 a, heat generated at the tip of the salient pole 3 a of the stator 3 due to eddy current is applied to the end cap 10 via the protrusion 13. Since it is transmitted, the heat of this part can also be efficiently radiated. Since the area for shielding the winding coil 7 by the protrusion 13 is large, the magnetic flux shielding performance is improved by that much, and the contact area with the winding coil 7 (bobbin 8) is further increased, so that the heat dissipation is further expanded. can do.
[0049]
Further, in the second embodiment, the inner diameter of the protrusion 13 is set to be substantially the same as the circle drawn by the tip of the salient pole 3 a of the stator 3. Since the rotor is supported by the end cap via the bearing, the inner diameter of the projection 13 of the end cap and the outer diameter of the rotor are kept high in coaxiality, and such setting is possible. By doing so, the thickness of the protrusion 13 can be maximized without hindering the rotation of the rotor 2, and the magnetic flux shielding and heat dissipation can be improved.
[0050]
In the second embodiment, two points will be described, namely, the point that the protrusion 13 of the end cap 10 is provided with a flat portion 13a and the point of the protrusion 13 that makes contact with the salient pole 3a of the stator 3. However, these do not necessarily have to be performed at the same time, and any one of them can achieve a certain effect. For example, the length of the cylindrical protrusion 12 as in the first embodiment described above can be increased so that the tip surface of the cylindrical protrusion 12 abuts on the salient pole 3 a of the stator 3.
[0051]
The end cap 10 of the second embodiment is also different from the first embodiment described above in that the end cap 10 is inserted into the housing 9 and fixed to the housing 9 with screws or the like. The axial length of the outer cylindrical portion 10a of the end cap 10 is not in contact with the stator 3 in order to improve the adhesion of the tip surface of the protrusion 13 of the end cap 10 to the salient pole 3a of the stator 3. This is because it is set so short.
[0052]
Third Embodiment FIG. 8 is a perspective view of an end cap showing the main part of a third embodiment of the SR motor according to the present invention. Components substantially the same as those of the first and second embodiments described above are denoted by the same reference numerals, and the description thereof is omitted.
[0053]
In the third embodiment, a part of the configuration of the protrusion 13 of the end cap 10 of the second embodiment described above is changed. That is, in addition to the protrusion 13 of the end cap 10, a plurality of convex portions 13b are integrally formed. A plurality of these convex portions 13 b are formed so as to be inserted along portions between the salient poles 3 a adjacent to each other in the stator 3 with the end cap 10 attached to the housing 9. By doing in this way, it is possible to further improve magnetic flux shielding, heat dissipation, and fixing reliability.
[0054]
In this case, since the end caps 10 are inserted and arranged from both ends of the stator 3, it is more effective if the tip portions of the protrusions 13 b corresponding to each other of the pair of end caps 10 are in contact with each other.
[0055]
In each of the embodiments described above, the winding coil 7 is configured by winding a coil wire around the bobbin 8, but the winding coil wound without using the bobbin is mounted on the salient pole 3a of the stator 3. Or it is applicable similarly even if it is the structure which winds a coil wire directly to this salient pole 3a, and makes it a winding coil.
[0056]
The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment includes all design changes and equivalents belonging to the technical scope of the present invention.
[0057]
For example, in each of the above-described embodiments, the application of the present invention to the SR motor has been described. Of course, other types of motors can also be applied. Further, the number of salient poles and the number of phases of the stator and the rotor are not limited to the above-described embodiment, and other types can be similarly applied.
[Brief description of the drawings]
FIG. 1 is a plan view, partly in section, showing the main part of a first embodiment of an SR motor according to the present invention.
FIG. 2 is an enlarged cross-sectional view of a main part of FIG.
3 is a perspective view showing the configuration of the end cap of FIG. 1. FIG.
4 is an enlarged cross-sectional view (a) of a main part of FIG. 1 and a cross-sectional view (b) showing a configuration of a related art corresponding thereto.
FIG. 5 is a plan view, partly in section, showing the main part of a second embodiment of the SR motor according to the present invention.
6 is an enlarged cross-sectional view of a main part of FIG.
7 is a perspective view showing a configuration of the end cap of FIG. 5. FIG.
FIG. 8 is a perspective view showing a configuration of an end cap of a third embodiment of the SR motor according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... SR motor 2 ... Rotor 2a ... Salient pole 3 ... Stator 3a ... Salient pole 4 ... Rotor core 5 ... Output shaft 6 ... Stator core 7 ... Winding coil 8 ... Bobbin 9 ... Housing 10 ... End cap 11 ... Bearings 12, 13 ... Projection 13a ... Flat part 13b ... Projection

Claims (6)

A stator having a plurality of salient poles projecting inward, winding coils provided so as to surround each of the stator salient poles, and a stator having a plurality of salient poles projecting outward. Motors equipped with a rotor,
Providing an end cap integrally formed with a protrusion that abuts the winding coil from the inside and fixes the winding coil;
The motor according to claim 1, wherein a tip of the protrusion is brought into contact with only an axial end surface of the salient pole of the stator. The motor according to claim 1, wherein the end cap is made of a nonmagnetic and conductive material. 3. The motor according to claim 1, wherein the protrusion is formed in a cylindrical shape having a central axis substantially coaxially with the rotation axis of the rotor. 4. The motor according to claim 1, wherein each portion of the protruding portion that comes into contact with the winding coil has a shape along the winding coil. The motor according to any one of claims 1 to 4, wherein the protrusion has a protrusion that is inserted into a portion between adjacent salient poles of the stator. 6. The motor according to claim 1, wherein an inner diameter of the protrusion is set to be substantially equal to an inner diameter of a tip of the salient pole of the stator.

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