JP6668984B2 - Rotating electric machine rotor - Google Patents

Description

  The present invention relates to a rotor of a rotating electric machine, and more particularly to a rotor in which a permanent magnet fixed in a magnet insertion hole of a rotor core is divided.

  Conventionally, for example, in Patent Document 1 below, two magnet insertion holes provided respectively corresponding to the magnetic poles of the rotor core, and a plurality of magnet insertion holes are divided in the width direction of the magnet insertion holes and arranged in the magnet insertion holes. A magnet set and an insulating tape that covers one end of each magnet set in the longitudinal direction are provided, and in the adjacent magnet insertion holes, the direction of the end covered with the insulating tape of the magnet set is made different. A rotating electrical machine rotor is disclosed.

JP 2015-106946 A

  In the rotating electric machine rotor disclosed in Patent Document 1, an eddy current path that can be formed between magnet sets respectively arranged in two magnet insertion holes provided in one magnetic pole can be cut off, and eddy current loss This has the effect of reducing

  However, as for the magnet set arranged in each magnet insertion hole, the two divided magnets constituting the magnet set are arranged in contact with each other, and the other side of the magnet set on which the insulating tape is not provided. The end contacts the inner wall surface of the magnet insertion hole formed in the rotor core. Therefore, when the insulating coating is not formed on the outer peripheral surface of the divided magnets constituting the magnet set, the two divided magnets are electrically conducted to form a loop-shaped eddy current path between the divided magnets, When the split magnet and the inner wall surface of the magnet insertion hole come into contact with each other and become electrically conductive, a loop-shaped eddy current path may be formed across the magnet set and the rotor core, resulting in a large eddy current loss. Could be.

  An object of the present invention is to provide a rotor of a rotating electric machine that can reliably suppress eddy current loss with a simple configuration when a divided magnet is used as a permanent magnet fixed to each magnet insertion hole.

  In the rotor of the rotating electric machine according to the present invention, permanent magnets are respectively inserted and fixed in a plurality of magnet insertion holes formed at predetermined intervals in a circumferential direction of the rotor core, and the permanent magnets in the respective magnet insertion holes are At least two divided magnets each extending in the axial direction of the rotor are arranged side by side, and the two divided magnets are respectively provided with insulating tape around the entire outer periphery around the axial direction at two or more locations separated in the axial direction of the rotor. Are wound, and the two or more insulating tapes are alternately arranged in the axial direction so as not to overlap with the two divided magnets.

  According to the rotor of the rotary electric machine according to the present invention, the at least two divided magnets constituting the permanent magnet fixed in each magnet insertion hole are in contact with each other via the insulating tape, so that they are electrically insulated from each other. Placed in Also, since the insulating tape is wound around the entire outer circumference of the divided magnet in the axial direction, the divided magnet may come into contact with the inner wall surface of the magnet insertion hole at the location where the insulating tape is wound. Also, the portion where the insulating tape is not wound does not contact the rotor core. Therefore, in a simple method of winding the insulating tape alternately so as not to overlap, a loop-shaped eddy current is generated between the plurality of permanent magnets arranged in the magnet insertion hole and between the plurality of divided magnets and the rotor core. A path can be prevented from being formed, and as a result, eddy current loss can be reliably suppressed.

FIG. 3 is an axial end view showing a rotor of the rotating electric machine according to the embodiment. FIG. 4 is a perspective view showing two divided magnets inserted into one magnet insertion hole in a separated state. FIG. 3 is a perspective view showing a state when the two split magnets shown in FIG. 2 are inserted into a magnet insertion hole. FIG. 4 is a diagram illustrating a state where the fixing material is filled after the permanent magnet illustrated in FIG. 3 is inserted and arranged in the magnet insertion hole.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this description, specific shapes, materials, numerical values, directions, and the like are examples for facilitating the understanding of the present invention, and can be appropriately changed according to uses, purposes, specifications, and the like. Further, when a plurality of embodiments and modified examples are included below, it is assumed from the beginning that these configurations are appropriately combined and used.

  FIG. 1 is an axial end view showing a rotor 10 of a rotary electric machine according to one embodiment. FIG. 1 shows the circumferential direction θ, the radial direction R, and the axial direction Z of the rotor 10. Hereinafter, the rotor 10 is simply referred to unless otherwise specified.

  When used as a drive source of a vehicle, the rotating electric machine that uses the rotor 10 is a motor generator that functions as an electric motor when the vehicle is running and that functions as a generator when the vehicle is braking. It is an electric machine. The rotating electric machine includes the rotor 10 shown in FIG. 1 and an annular stator that is arranged on the outer peripheral side of the rotor 10 with a predetermined gap and around which a winding coil is wound. In FIG. 1, illustration of the stator is omitted.

  The rotor 10 includes a rotating shaft 12, a rotor core 14, a plurality of magnet insertion holes 18, 20 provided in the rotor core 14, and permanent magnets 22 fixed in the respective magnet insertion holes 18, 20. . When the rotor 10 is used in a rotating electric machine, both ends in the axial direction of the rotating shaft 12 integrated with the rotor core 14 are rotatably supported by bearings, and cooperate with a stator (not shown) and the rotating shaft 12 together with the rotor core 14. Rotates. Thus, in the rotating electrical machine, the rotating shaft 12 is an output shaft that outputs torque.

  The rotor core 14 is a laminated body in which a predetermined number of annular magnetic thin plates are laminated. As the magnetic thin plate, for example, a magnetic steel plate punched out can be used. The rotor core 14 includes a circular center hole 15 through which the rotating shaft 12 passes, and a plurality of magnet insertion holes 18 and 20.

  The rotor core 14 is formed of a laminated body of magnetic thin plates in order to suppress an eddy current that may be generated in the rotor core 14. Both surfaces of the web of the magnetic thin plate before being formed into a predetermined shape are provided with insulating coats or the like. An insulation process is performed. As a result, the stacked magnetic thin plates are electrically insulated from each other, and an eddy current that can be generated by an externally fluctuating magnetic field can be divided into small loops, so that eddy current loss can be suppressed. Note that the inner wall surface of the magnet insertion hole 18 and the like is in a state where the conductive magnetic thin plate is exposed because the insulating coating or the like is removed during the punching process.

  The magnet insertion holes 18 and 20 are formed in the outer peripheral portion of the rotor core 14 at predetermined intervals in the circumferential direction. The magnet insertion holes 18 and 20 are holes for embedding and arranging permanent magnets forming the magnetic poles of the rotor 10, and have a substantially rectangular shape in the end view of FIG. Here, for the magnet insertion holes 18 and 20, the direction along the long side of the substantially rectangular shape is referred to as the width direction. In the rotor 10 of the present embodiment, the number of magnetic poles is 8, and each magnetic pole is arranged in a substantially V-shape with a predetermined inclination angle, and two magnet insertions penetrating the rotor core 14 in the axial direction Z. Holes 18 and 20 are formed.

  The permanent magnets 22 are magnets that are arranged in the magnet insertion holes 18 and 20, respectively, and form the magnetic poles of the rotor 10. The permanent magnet 22 is composed of two divided magnets 22a and 22b arranged in the magnet insertion holes 18 and 20 in the width direction. Each of the split magnets 22a and 22b extends in the axial direction Z of the rotor 10, respectively. The permanent magnets 22 arranged in the magnet insertion holes 18 and 20 may be configured by arranging three or more divided magnets.

  In the present embodiment, by arranging the two divided magnets 22a and 22b side by side, the outer shape conforming to the rectangular shape which is the shape of the magnet insertion holes 18 and 20 is exhibited. In the example of FIG. 1, the permanent magnets 22 each composed of two divided magnets 22a and 22b are arranged in the magnet insertion holes 18 and 20, respectively. Dividing the permanent magnet 22 arranged in one magnet insertion hole in the width direction in this manner reduces the eddy current loss by dividing the loop of the eddy current generated in the magnet by the fluctuating magnetic field from the outside into small portions. That's why.

  In one magnetic pole, the two magnet insertion holes 18 and 20 are arranged in a substantially V shape, and accordingly, the two permanent magnets 22 are also arranged in a substantially V shape. The two permanent magnets 22 forming one magnetic pole both have N poles or S poles on the outer circumferential side (ie, radially outer side) facing the stator (not shown). The polarities of the magnetic poles adjacent in the circumferential direction are opposite to each other. For example, the polarity of the magnetic pole A in FIG. 1 is N-pole on the surface on the radially outer peripheral side, and the permanent magnet 22 of the magnetic pole B adjacent in the circumferential direction has the S-polarity on the outer peripheral surface. It is arranged so that it becomes.

  As the material of the permanent magnet 22, rare earth magnets such as a neodymium magnet mainly containing neodymium, iron and boron, and a samarium cobalt magnet mainly containing samarium and cobalt are used. Alternatively, a ferrite magnet, an alnico magnet, or the like may be used. The surface of the permanent magnet 22 is not subjected to an electrical insulation treatment such as an insulation coating. As a result, it is possible to save time and labor for insulating coating processing and the like, thereby reducing costs.

  Next, the configuration of the permanent magnet 22 inserted and fixed in the magnet insertion holes 18 and 20 will be described in detail with reference to FIGS. FIG. 2 is a perspective view showing two split magnets 22a and 22b inserted into the magnet insertion holes in a separated state. FIG. 3 is a perspective view showing a state where the two split magnets 22a and 22b shown in FIG. 2 are inserted into the magnet insertion holes. 2 and 3, the axial direction Z of the rotor 10 (that is, the rotor core 14) is indicated by an arrow.

  As described above, the permanent magnets 22 composed of the two divided magnets 22a and 22b are inserted and arranged in the magnet insertion holes 18 and 20, respectively. Since the configuration of the permanent magnets 22 inserted and arranged in the magnet insertion holes 18 and 20 is the same, one permanent magnet 22 will be described below without distinguishing the magnet insertion holes 18 and 20.

  As shown in FIG. 2, the two divided magnets 22a and 22b constituting the permanent magnet 22 are formed in the same shape and size. That is, each of the divided magnets 22a and 22b has a rectangular parallelepiped shape extending along the axial direction Z, and has the same axial length.

  Also, at each of the divided magnets 22a and 22b, insulating tapes 24a and 24b are wound around the entire outer circumference around the axial direction at two locations separated in the axial direction Z. More specifically, the insulating tape 24a is attached so as to cover the entire outer periphery of one end in the axial direction Z of each of the divided magnets 22a and 22b. Further, the insulating tape 24b is attached at a position separated from the insulating tape 24a in the axial direction Z on each of the divided magnets 22a and 22b, and does not cover the other end of the divided magnets 22a and 22b in the axial direction Z. It is attached. As a result, between the insulating tapes 24a and 24b, the magnet portion 23 not subjected to the insulation treatment is exposed, and the outer peripheral surface at the other end in the axial direction Z also becomes the magnet portion 25 similarly exposed. I have.

  Here, assuming that the width of the insulating tapes 24a, 24b in the axial direction Z is W, the distance D between the insulating tapes 24a, 24b in each of the divided magnets 22a, 22b is set to be larger than the width W (D> W). ). By setting in this way, when the other divided magnet 22b is arranged in the opposite direction in the axial direction Z with respect to one divided magnet 22a as described later, the insulating tapes 24a, 24b in the respective divided magnets 22a, 22b. The insulating tape 24b comes into contact with the magnet portion 23 exposed therebetween.

  The insulating tapes 24a and 24b electrically insulate between the divided magnets 22a and 22b and between the divided magnets 22a and 22b and the rotor core 14 when the permanent magnet 22 is inserted into the magnet insertion holes 18 and 20. Has functions. As the insulating tapes 24a and 24b, for example, an adhesive tape in which an adhesive layer is provided on one surface of an insulating resin film can be used. Although not shown, the insulating tapes 24a and 24b have a predetermined thickness t.

  In the present embodiment, the insulating tapes 24a and 24b are not disposed on all of the outer peripheral surfaces of the divided magnets 22a and 22b, but are partially disposed so as to partially cover the divided magnets 22a and 22b in the axial direction Z. You. This can reduce the trouble of arranging the insulating tape on the divided magnets 22a and 22b, and reduce the amount of the insulating tapes 24a and 24b used.

  As described above, when the divided magnets 22a and 22b on which the insulating tapes 24a and 24b are wound are inserted into the magnet insertion holes 18 and 20 (see FIG. 1) of the rotor core 14, they are aligned as shown in FIG. Be placed. In the present embodiment, for each of the divided magnets 22a and 22b similarly wound with the insulating tapes 24a and 24b, the other divided magnet 22b is arranged in the opposite direction in the axial direction Z with respect to one divided magnet 22a. State. As a result, in the two divided magnets 22a and 22b constituting the permanent magnet 22, the insulating tapes 24a and 24b are alternately arranged so as not to overlap in the axial direction Z.

  More specifically, when FIG. 3 is viewed in order from the upper side, the insulating tape 24a of one divided magnet 22a is opposed to and contacts the exposed magnet portion 25 of the other divided magnet 22b. Next, the insulating tape 24b of the other split magnet 22b faces and contacts the exposed magnet portion 23 of the one split magnet 22a at a position shifted in the axial direction Z from the insulating tape 24a of the one split magnet 22a. ing. Next, the insulating tape 24b of one divided magnet 22a is opposed to and contacts the exposed magnet portion 23 of the other divided magnet 22b at a position shifted in the axial direction Z from the insulating tape 24b of the other divided magnet 22b. ing. The insulating tape 24a of the other split magnet 22b is opposed to and contacts the exposed magnet portion 25 of the one split magnet 22a at a position shifted in the axial direction Z from the insulating tape 24b of the one split magnet 22a.

  Thus, the two divided magnets 22a and 22b are configured as one permanent magnet 22, and the insulating tape 24a contacts the exposed magnet portion 25, and the insulating tape 24b contacts the exposed magnet portion 23. Further, the permanent magnet 22 of the present embodiment is configured such that the portions where the insulating tapes 24a and 24b are wound do not overlap each other. Thereby, in the permanent magnet 22 in the present embodiment, the insulating tapes 24a and 24b come into contact with the magnet portions 23 and 25, and the magnet portions 23 and 25 are separated from each other because the insulating tapes 24a and 24b have a predetermined thickness t. Do not touch. Therefore, the two split magnets 22a and 22b are electrically insulated by the insulating tapes 24a and 24b.

  The permanent magnet 22 constituted by arranging the two divided magnets 22a and 22b in this manner is provided in one of the magnet insertion holes 18 and 20 formed in the rotor core 14 in one axial direction, as indicated by arrows in FIG. Is inserted and arranged from the opening.

  FIG. 4 is a view showing a state where the fixing material is filled after the permanent magnet 22 shown in FIG. 3 is inserted and arranged in the magnet insertion holes 18 and 20.

  After the permanent magnets 22 are inserted into the magnet insertion holes 18 and 20 of the rotor core 14, respectively, the openings of the magnet insertion holes 18 and 20 located on one side in the axial direction of the rotor core 14 as shown by arrows in FIG. The fixing material is injected from the part. Here, for example, a molten resin is used as the fixing material.

  In the example shown in FIG. 4, the fixing material is injected from above. At this time, since the insulating tape is not wound around the magnet portion 25 of the divided magnet 22b, a gap corresponding to the thickness t or more of the insulating tapes 24a and 24b is formed between the magnet insertion holes 18 and 20. Have been. Therefore, the injected fixing material is first injected all around the magnet portion 25 of the other split magnet 22b.

  As described above, the insulating tape 24b of the other split magnet 22b contacts the magnet portion 23 of the one split magnet 22a, and the insulating tapes 24a and 24b do not overlap. Therefore, a gap corresponding to the thickness t of the insulating tapes 24a and 24b is formed between the magnet portion 25 of the other split magnet 22b and the magnet portion 23 of the one split magnet 22a in the magnet insertion holes 18 and 20. It is formed between wall surfaces. Therefore, the fixing material is injected through this gap and is filled around the magnet portion 23 of the one divided magnet 22a. Similarly, the fixing material is filled from the periphery of the magnet portion 23 of the one divided magnet 22a to the periphery of the magnet portion 23 of the other divided magnet 22b, and then from the periphery of the magnet portion 23 of the other divided magnet 22b, It is filled around the magnet portion 25 of the split magnet 22a. As the fixing material injected around the permanent magnet 22 hardens in this manner, the divided magnets 22 a and 22 b constituting the permanent magnet 22 are fixed in the magnet insertion holes 18 and 20.

  As described above, according to the rotor 10 of the present embodiment, the two divided magnets 22a and 22b constituting the permanent magnet 22 fixed in the magnet insertion holes 18 and 20 are in contact with each other via the insulating tapes 24a and 24b. Therefore, they are arranged in a state of being electrically insulated from each other. Further, since the insulating tapes 24a, 24b are wound around the entire outer circumference of the divided magnets 22a, 22b in the axial direction, the permanent magnets 22 are placed on the inner wall surfaces of the magnet insertion holes 18, 20 with the insulating tapes 24a, 24b. May come into contact with the wound portion, but do not contact the rotor core 14 at the portion where the insulating tapes 24a and 24b are not wound (that is, the magnet portions 23 and 25). The same applies to the case where the permanent magnet 22 is inclined with respect to the axial direction Z in the magnet insertion holes 18 and 20. Therefore, the two divided magnets 22a and 22b are arranged side by side in the magnet insertion holes 18 and 20 by a simple method of alternately winding the insulating tapes 24a and 24b so as not to overlap the two polarizing magnets 22a and 22b. In addition, it is possible to prevent a loop-shaped eddy current path from being formed between the two divided magnets 22a and 22b and the rotor core 14, and as a result, eddy current loss can be reliably suppressed.

  Further, in the rotor 10 of the present embodiment, the two divided magnets 22a and 22b in which the insulating tapes 24a and 24b are wound in the same manner are configured such that one divided magnet is opposite to the other divided magnet 22b in the axial direction. The permanent magnets 22 were arranged side by side. Therefore, there is no need to prepare two types of split magnets in which the insulating tape is wound differently, and the manufacturing is facilitated and the cost can be reduced.

  Further, in the rotor 10 of the present embodiment, the permanent magnets 22 are arranged so that the insulating tapes 24a, 24b of the two divided magnets 22a, 22b constituting the permanent magnet 22 do not overlap with each other, so that the permanent magnets 22 can be inserted into the magnet insertion holes 18, 20. When the fixing material is injected after being inserted and arranged in the inside, it can be surely injected and filled around the exposed magnet portions 23 and 25 of the divided magnets 22a and 22b, and the permanent magnet 22 is firmly fixed by the fixing material. Fixing can be realized. Further, since the insulating tapes 24a and 24b do not overlap each other, there is an advantage that the permanent magnet 22 can be reduced in size, the magnetic flux density increases, and the torque increases.

  It should be noted that the present invention is not limited to the configurations of the above-described embodiment and the modifications thereof, and various changes can be made within the matters described in the claims of the present application and their equivalents.

  For example, in the above description, the form in which the insulating tapes 24a and 24b are wound at two places separated in the axial direction for each of the divided magnets 22a and 22b has been described, but the present invention is not limited to this. The insulating tape may be wound at three or more locations separated in the axial direction in each divided magnet.

  In the above description, an example in which two divided magnets 22a and 22b are arranged side by side in the width direction of the rectangular magnet insertion holes 18 and 20 has been described. Here, when the width direction of the magnet insertion hole is formed along the circumferential direction or the radial direction of the rotor, at least two divided magnets may be arranged side by side in the circumferential direction or the radial direction of the rotor core.

  Reference Signs List 10 rotor, 12 rotation axis, 14 rotor core, 15 center hole, 18, 20 magnet insertion hole, 22 permanent magnet, 22a, 22b divided magnet, 23, 25 magnet part, 24a, 24b insulating tape, A, B magnetic pole, D distance , R radial direction, W width, Z axis direction, θ circumferential direction.

Claims (1)

Permanent magnets are respectively inserted and fixed in a plurality of magnet insertion holes formed at predetermined intervals in the circumferential direction of the rotor core, a rotor of the rotating electrical machine,
The permanent magnet in each of the magnet insertion holes is configured by arranging at least two divided magnets each extending in the axial direction of the rotor,
At each of the two split magnets, at two or more locations separated in the axial direction of the rotor, an insulating tape is wound around the entire outer periphery around the axial direction,
The two or more insulating tapes are arranged alternately in the axial direction so as not to overlap with the two divided magnets,
Rotor of rotating electric machine.

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