JP4970974B2 - Rotating electric machine - Google Patents

Description

  The present invention relates to a rotary electric machine, and more particularly to reduction of thrust force of a so-called axial gap type motor in which a rotor and a stator face each other along an axial direction of the rotor.

  Even if the axial gap type motor is thinned in the direction of the rotation axis of the rotor, a sufficient permanent magnet can be provided. Further, the space factor of the armature winding can be easily increased, and the output density and torque density are improved.

  However, unlike the radial gap type motor, the stator faces the rotor along the direction of the rotation axis, so that the suction force (thrust force) acting between the two is not canceled by the rotation. In view of this, a technique has been proposed in which the thrust force acting on the rotor and the stator in one rotating electric machine is made to work in opposite directions to cancel each other.

  As one aspect thereof, a configuration is conceivable in which the rotors face each other from opposite directions along the rotation axis direction with respect to one stator. In this case, however, the pair of rotors requires twice the permanent magnets provided on the rotor.

  In the following Patent Document 1, a technique of providing a permanent magnet only on one rotor is proposed. However, the rotating shaft is held by two rotors, which makes it difficult to hold the rotating shaft. In addition, a structure in which torsional vibration is likely to occur is adopted.

  As another aspect, a mode is conceivable in which the stators face each other from opposite directions along the rotation axis direction with respect to one rotor. However, in this case, the number of places where the armature winding provided on the stator is wound is twice as large as the pair of stators. This increases the number of processes and increases the number of locations where the armature windings are connected, thereby increasing the dead space.

  Patent Document 2 below proposes a technique that does not increase the number of armature windings by providing one main winding of two stators and an auxiliary winding on the other in a single-phase induction motor. However, since the current flowing through the main winding is usually larger than the current flowing through the auxiliary winding, the thrust force is not sufficiently offset.

  Assuming that this technique is applied to a three-phase stator, coils are usually inserted in order for each phase, so that the three stators are wound. Alternatively, two phases are provided on one stator, and one remaining phase is provided on the other stator.

  However, even in this case, by providing coils on the stators on both sides, crossovers and connections increase, and the connection between the upper and lower stators limits the outer diameter of the rotor.

  In addition, Patent Document 3 is further cited as a document related to the present invention.

Japanese Patent Laid-Open No. 61-185040 JP-A-1-174248 JP 2006-353078 A

  The present invention has been made in view of the above problems, and in an axial gap type rotating machine, the number of armature windings is increased as compared with a rotating electric machine having a stator of 1, while having a stator of 2. An object of the present invention is to provide a technique for canceling the magnetic attractive force (thrust force) acting on the rotor from both stators.

  A first aspect of the rotating electrical machine according to the present invention includes a rotor (200) that rotates about a rotation axis (Q), and a first stator (100) that faces the rotor along the rotation axis. And a second stator (300) facing the rotor on the opposite side of the first stator along the rotation axis. The rotor includes a plurality of magnetic poles (22; 27) arranged along a circumferential direction with respect to the rotation axis, and a magnetic flux that is provided on the magnetic pole on the second stator side and flows into and out of the magnetic pole. A magnetic plate (23) that is short-circuited between the magnetic poles and partially flows into and out of the second stator. The first stator opposes the magnetic poles with a space therebetween, and a plurality of magnetic cores (12) arranged along the circumferential direction, and a plurality of armatures wound around at least one of the magnetic cores. Winding (13). The second stator has a stator magnetic plate (300) facing the magnetic plate with a space therebetween.

And, the first stator (100) further includes a back yoke (11) connecting the magnetic core (12) in said rotor (200) and opposite. The thickness of the stator magnetic plate (300) along the rotation axis (Q) is smaller than the thickness of the back yoke along the rotation axis.

A second aspect of the rotating electrical machine according to the present invention is the first aspect, wherein the thickness of the magnetic plate for stator (300) along the rotation axis (Q) is the rotation of the back yoke. The thickness along the rotation axis of the magnetic plate (23) is smaller than the thickness along the axis.

A third aspect of the rotating electrical machine according to the present invention is any one of the first to second aspects, and fixes the stator magnetic plate (300) on the opposite side to the rotor (200). A member (6) is further provided.

A fourth aspect of the rotating electrical machine according to the present invention is any one of the first to third aspects, and the magnetic plate for stator (300) is made of a dust core.

A fifth aspect of the rotating electrical machine according to the present invention is any one of the first to third aspects , wherein the magnetic plate for stator (300) is formed by winding a steel plate around the rotation axis (Q). It is a wound core.

A sixth aspect of the rotating electric machine according to the present invention, in the fifth aspect, prior SL back yoke (11) is a laminated core formed by laminating steel plates along said rotary shaft. And the thickness of the said steel plate of the said laminated iron core is larger than the thickness of the said steel plate of the said wound iron core.

A seventh aspect of the rotating electrical machine according to the present invention is any one of the first to sixth aspects, wherein the rotor (200) includes a first recess (241) that holds the magnetic pole (12). And a non-magnetic holder (24) provided with a hole (240) for fitting the rotating shaft (5).

The 8th aspect of the rotary electric machine concerning this invention is the 7th aspect, Comprising: The said holder (24) and the said magnetic board (23) closely_contact | adhere on a surface.

A ninth aspect of the rotating electrical machine according to the present invention is the eighth aspect, and the second recess (24b) is provided on the surface of the magnetic plate (23) in close contact with the holder (24). The second recess is provided with an adhesive.

First 0 embodiment of the rotary electric machine according to the present invention, in the eighth aspect, the holder (24), the second recess (24d) is provided to fit said magnetic plate (23).

First one aspect of the rotating electric machine according to the present invention, in any one of the first to 1 0 embodiment, the magnetic plate (23) is formed by punching a sheet of steel.

The first and second aspect of the rotating electric machine according to the present invention, in any one of the first to 1 0 embodiment, the magnetic plate (23), said near the magnetic pole center of the rotor (200) The steel plate (231) divided in the circumferential direction is combined.

Embodiment of the first 3 of the rotary electric machine according to the present invention, in any one of the first to 1 second embodiment, the magnetic pole (22) is a permanent magnet.

The first fourth aspect of the rotating electric machine according to the present invention, in the first third aspect, the rotor (200) is provided on the first stator (100) side of the pole (22) The magnetic body (21) is further included.

First fifth aspect of the rotating electric machine according to the present invention, in any one of the first 3 to the first 4 embodiment, the rotor (200), the relative said magnetic plate (23) a It further has a magnetic body (25) arranged alternately with respect to the magnetic pole in the circumferential direction on the one stator side.

Embodiment of the first 6 of the rotary electric machine according to the present invention, in any one of the first to 1 5 embodiment, the between the rotor (200) and said first stator (100) The length along the rotation axis (Q) is equal to the length along the rotation axis between the rotor and the second stator (300).

  According to the first aspect of the rotating electrical machine of the present invention, the thrust force acting between the rotor and the first stator and the thrust force acting between the rotor and the second stator are offset. Thereby, the loss of the bearing which supports a rotor and the improvement of a lifetime are obtained. In addition, the configuration of the second stator can be simplified. Further, since the magnetic plate is provided on the rotor, even if the so-called air gap between the rotor and the second stator is small, the thrust force acting on both is reduced, and the rotor and the first stator It becomes easy to cancel out the thrust force acting between the two.

Further , by providing the back yoke on the first stator, the magnetic field generated by the armature current flowing in the armature winding can be efficiently supplied to the rotor. Moreover, since the magnetic plate allows only a part of the magnetic flux flowing into and out of the magnetic pole to flow into and out of the magnetic plate for the stator, the thickness required for the magnetic plate for the stator is small, so that the material can be saved.

According to the second aspect of the rotating electrical machine of the present invention, leakage of magnetic flux from the stator magnetic plate to the opposite side of the rotor is eliminated, and the thrust force acting between the rotor and the second stator is reduced. Not too much.

According to the third aspect of the rotating electrical machine of the present invention, the mechanical strength of the stator magnetic plate is reinforced.

According to the 4th aspect of the rotary electric machine concerning this invention, the attachment to another member is easy.

According to the fifth aspect of the rotating electrical machine of the present invention, the magnetic flux flowing into and out of the rotor passes through the stator magnetic plate in the rotation axis direction and the circumferential direction. The magnetic resistance of the stator magnetic plate can be reduced.

According to the sixth aspect of the rotating electrical machine of the present invention, the magnetic flux flowing into and out of the rotor passes through the stator magnetic plate in the rotation axis direction and the circumferential direction. The magnetic resistance of the stator magnetic plate can be reduced. Further, since the magnetic flux flowing through the back yoke passes in a direction perpendicular to the rotation axis, the magnetic resistance of the back yoke along the path through which the magnetic flux passes can be reduced. In addition, the thickness of the steel sheet of the laminated core is increased to increase the mechanical strength when holding the magnetic core or fixing it to other parts, and the thickness of the steel sheet of the wound core is reduced to facilitate mechanical processing called winding. To do.

According to the seventh aspect of the rotating electrical machine of the present invention, the magnetic pole is positioned and the rotating shaft is fixed to the rotor without short-circuiting the magnetic flux between the magnetic poles.

According to the eighth aspect of the rotating electrical machine of the present invention, the adhesion strength between the holder and the magnetic plate is increased.

According to the ninth aspect of the rotating electrical machine of the present invention, the amount of adhesive necessary for the close contact between the holder and the magnetic plate can be reduced.

According to a first 0 embodiment of the rotary electric machine according to the present invention, it is easy to position the magnetic plate.

According to the first aspect of the rotating electrical machine of the present invention, the magnetic plate can be easily formed. Since the magnetic plate is on the side opposite to the first stator, the fluctuation of the magnetic flux therein is small. Therefore, even with a magnetic plate obtained by punching a single steel plate, the problem of magnetoresistance is small.

According to the first and second aspects of the rotating electrical machine according to the present invention, since the divided portion of the steel plate is the center of the magnetic pole, the divided steel plate is used without increasing the magnetic resistance of the path for short-circuiting the magnetic flux between the magnetic poles. Thus, a magnetic plate can be obtained.

According to a first third aspect of the rotating electric machine according to the present invention, it is possible to produce a rotor in a simple manner.

According to a first 4 embodiment of the rotary electric machine according to the present invention, it is possible to reduce the eddy current loss and demagnetization in the permanent magnet.

According to a first fifth aspect of the rotating electric machine according to the present invention, increasing the so-called q-axis inductance, to generate reluctance torque.

According to a first sixth aspect of the rotating electric machine according to the present invention, it is possible to reduce the two so-called air gap, it can be reduced in length along the rotation axis of the rotary electric machine.

First embodiment.
FIG. 1 is an exploded perspective view showing the rotating electrical machine according to the first embodiment of the present invention in the direction of the rotation axis Q. FIG. The direction in which the rotation axis Q extends will be described below in the Z-axis direction of the coordinate axis.

  FIG. 2 is a cross-sectional view showing the rotating electric machine without being disassembled in the direction of the rotation axis Q. FIG. 2 shows a cross section including the rotation axis Q and parallel to the Z axis. However, in FIG.1 and FIG.2, the structure which couple | bonds the rotating shaft normally provided in a rotary electric machine and this and a rotor is abbreviate | omitted.

  The rotating electrical machine includes a first stator 100, a rotor 200, and a second stator 300. The rotor 200 rotates around the rotation axis Q. The first stator 100 faces the rotor 200 along the rotation axis Q. The second stator 300 faces the rotor 200 along the rotation axis Q on the side opposite to the first stator.

  The rotor 200 has permanent magnets 22 arranged along the circumferential direction with respect to the rotation axis Q, and these alternately present a plurality of magnetic poles. By employing the permanent magnet 22, a rotor that generates a field magnetic flux can be easily produced.

  The rotor 200 has a magnetic plate 23 and is provided on the permanent magnet 22 on the second stator 300 side.

  FIG. 3 is a cross-sectional view showing a developed cross section along the circumferential direction of the rotor 200 at and around the position where one permanent magnet 22 exists. The permanent magnet 22 usually has anisotropy in the Z-axis direction. Thereby, the magnetization when magnetized is high, and the field magnetic flux can be supplied to both the first stator 100 and the second stator 300 with the least leakage. FIG. 3 illustrates the case where the magnetic poles of the S pole and the N pole are respectively shown on the first stator 100 and the second stator 300 side, but the positions of these magnetic poles are the positions of the permanent magnet 22. Depends on the location.

  The magnetic plate 23 partially shorts the magnetic flux flowing into and out of the permanent magnet 22 between the permanent magnets 22 and partially flows into and out of the second stator 300 side. The magnetic plate 23 is provided with a hole 230 for passing a rotating shaft (not shown).

  The first stator 100 has a plurality of magnetic cores 12 and a plurality of armature windings 13. The magnetic cores 12 are arranged along the circumferential direction. Here, the armature winding 13 is wound around the magnetic core 12 in a concentrated winding manner. However, the armature winding 13 may be wound around a plurality of magnetic cores 12 and may take the form of distributed winding. The magnetic core 12 and the armature winding 13 are opposed to each other with an interval so as not to contact the rotor 200.

  Here, although the case where the 1st stator 100 further has the magnetic board 14 is illustrated, this may be abbreviate | omitted.

  The magnetic plate 14 is provided on the magnetic core 12 from the rotor 200 side, and has a slit 141 and a hole 140 formed therein. The hole 140 is for passing the rotating shaft, and the slit 141 is for preventing the magnetic cores 12 from being magnetically short-circuited. The slit 141 extends in the radial direction, and both end portions thereof are defined by the thin portion 143. Desirably, the hole 140 is not in close proximity to the rotating shaft. This is to prevent the magnetic flux from being short-circuited through the rotating shaft of the magnetic material.

  The magnetic plate 14 has a thin portion 143 and a wide portion 142 that is connected to each other and is provided for each magnetic core 12. The wide portion 142 has a function of increasing the facing area with the rotor 200, and has a dimension at least in the circumferential direction larger than that of the magnetic core 12. Since the thin portion 143 has a thickness that is easily magnetically saturated, the wide portions 142 are mechanically connected to each other, and the wide portions 142 are magnetically independent from each other together with the slit 141.

  By providing the magnetic plate 14, the magnetic flux density in the air gap is improved and the flatness of the surface of the first stator 100 on the air gap side is improved, so that the air gap can be further reduced.

  In addition, the thickness of the magnetic plate 14 may be reduced at a position where the slit 141 and the thin portions 143 at both ends thereof exist, and the wide portions 142 may be connected to each other over the entire radial direction. In this case, it is desirable that the thickness of the magnetic plate 14 at the position is such that it is easily magnetically saturated, like the thin portion 143.

  The second stator 300 is a stator magnetic plate 300 and is opposed to the magnetic plate 23 with a gap. The interval corresponds to a so-called air gap between the second stator 300 and the rotor 200. The stator magnetic plate 300 is provided with a hole 30 through which the rotary shaft passes.

  A thrust force acting between the rotor 200 and the first stator 100 (hereinafter also referred to as “first thrust force”) and a thrust force acting between the rotor 200 and the second stator 300 (hereinafter referred to as “second thrust”). “Thrust force” is also the opposite direction, so they can be offset. Thereby, the loss of the bearing (illustration omitted) which supports the rotor 200 and the lifetime improvement are obtained. Moreover, the configuration of the second stator 300 is simple. In particular, if the air gap is the same, the second thrust force is greater than the first thrust force, so the difference can be offset by short-circuiting the magnetic flux 23.

  Further, the magnetic plate 23 causes the magnetic flux flowing into and out of the permanent magnet 22 to partially flow into and out of the second stator 300 side. Therefore, even if the so-called air gap between the rotor 200 and the second stator 300 is small, the second thrust force can be reduced. Therefore, it becomes easy to cancel the second thrust force and the first thrust force.

  Since such cancellation is easy, the length of the air gap on the first stator 100 side and the air gap on the second stator 300 side can be made equal. This is advantageous in that the minimum air gap required from the mechanical accuracy can be adopted, and the length along the rotation axis Q of the rotating electrical machine can be reduced.

  If the air gap is reduced, the magnetic resistance can be minimized, the operating point magnetic flux density can be increased, and the energy of the permanent magnet 22 can be used effectively.

  It is also conceivable that the difference between the first thrust force and the second thrust force varies due to the excitation of the first stator 100. Therefore, it is also possible to adjust by making one of the air gaps variable. At this time, a mechanism may be provided so that the second stator 300 without a coil can be moved slightly in the Z-axis direction.

  The first stator 100 further includes a back yoke 11. On the side opposite to the rotor 200, the back yoke 11 connects the magnetic core 12 at its surface 11a. By providing the back yoke 11, the magnetic field generated by the armature current flowing through the armature winding 13 can be efficiently supplied to the rotor 200. The back yoke 11 is provided with a hole 110 for passing the rotating shaft.

  The thickness of the stator magnetic plate 300 along the rotation axis Q may be smaller than the thickness of the back yoke 11 along the rotation axis Q. This is because the magnetic plate 23 causes the magnetic flux flowing into and out of the permanent magnet to flow into and out of the stator magnetic plate 300 only partially. Therefore, the material required for the stator magnetic plate 300 can be saved.

  For example, the thickness of the stator magnetic plate 300 is selected to be smaller than the thickness of the back yoke 11 by the thickness of the magnetic plate 23. This is because the leakage of magnetic flux from the stator magnetic plate 300 to the opposite side of the rotor 200 is eliminated, and the second thrust force is not excessively reduced. If the strength of the stator magnetic plate 300 is thereby reduced, the strength may be increased by bringing the stator magnetic plate 300 into close contact with another member such as a holder provided separately in the rotating machine 200. The holder will be described later.

  The rotor 200 further includes a magnetic body 21 on the first stator 100 side of the permanent magnet 22. Of course, in order not to short-circuit the magnetic poles exhibited by the permanent magnets 22, it is desirable that the interval between the magnetic bodies 21 be at least twice the air gap between the first stator 100 and the rotor 200. For example, the magnetic body 21 is formed in the same shape as the permanent magnet 22 and is provided in alignment therewith.

  Even if a demagnetizing field is applied to the rotor 200 due to the armature current flowing through the armature winding 13 and the first stator 100 being excited, the demagnetizing field acting on the permanent magnet 22 is mitigated by the magnetic body 21. Is done.

  Further, when the permanent magnet 22 is formed of a sintered rare earth magnet, its resistivity is small, and eddy currents are likely to occur. However, when the magnetic body 21 is formed of a material having high resistivity, for example, a dust core, the magnetic field excited by the first stator 100 does not act up to the permanent magnet 22, and heat generated by eddy current inside the permanent magnet 22 Loss can be reduced. This is more effective as the carrier frequency component of the magnetic field is higher.

  On the other hand, since the second stator 300 is not excited, the function of the magnetic body 21 is not required for the magnetic plate 23. However, the first thrust force and the second thrust force can be balanced by short-circuiting a part of the magnetic flux flowing into and out of the permanent magnet 22. A part of the field magnetic flux generated by the permanent magnet 22 and interlinked with the first stator 100 is used to rotate the rotor 200, so that the magnetic plate 23 interlinks with the second stator 200. Field magnetic flux is reduced.

  Next, the materials of the first stator 100 and the second stator 300 will be illustrated. As a material of the stator magnetic plate 300 employed as the second stator 300, a dust core can be employed. In this case, attachment to another member, for example, a frame of a rotating electrical machine becomes easy.

  A wound iron core wound around the rotation axis Q is preferable. Since the magnetic flux flowing into and out of the rotor 200 passes through the stator magnetic plate 300 in the Z-axis direction and the circumferential direction, the magnetic resistance of the stator magnetic plate 300 along the path through which the magnetic flux passes is reduced. Because you can.

  The wound iron core is preferably made of a thin plate. Specifically, for example, an electromagnetic steel plate of 0.35 mm or less, an amorphous steel plate of less than 0.1 mm, or the like can be considered. Annealing may be performed in order to remove distortion caused by winding.

  On the other hand, the back yoke 11 of the first stator 100 is preferably a laminated iron core in which steel plates are laminated along the Z axis. This is because the magnetic flux flowing through the back yoke 11 passes in a direction perpendicular to the Z-axis, so that the magnetic resistance of the back yoke 11 along the path through which the magnetic flux passes can be reduced.

  The thickness of the steel sheet of the laminated core that will be the back yoke 11 is desirably larger than the thickness of the steel sheet of the wound core that will be the stator magnetic plate 300. While the thickness of the steel sheet of the laminated core can be increased to increase the mechanical strength when the magnetic core 12 is held or fixed to other parts, the mechanical strength of winding is achieved while reducing the thickness of the steel sheet of the wound core. Processing is facilitated.

  Moreover, although the magnetic core 12 may employ a dust core, since the magnetic flux flowing through the magnetic core 12 flows along the Z-axis, a wound core that is wound using an axis parallel to the Z-axis direction is employed. It is also preferable to do.

  When the steel plates laminated as described above are employed as the back yoke 11, it is particularly preferable that the magnetic core 12 is provided so as to enter a certain depth from the surface 11a to the back yoke 11. In the magnetic core 12, the flow of magnetic flux in the Z-axis direction component is main, and in the steel sheet laminated in the Z-axis direction in the back yoke 11, the magnetic resistance increases due to gaps between the steel film and the gap between the laminations. is there.

  Since the magnetic plate 23 is in contact with the permanent magnet 22 on the side opposite to the first stator 100, it is considered that the fluctuation of the magnetic flux is small. Therefore, it is sufficient to make a single steel plate. For example, it is composed of a 0.35 mm or 0.5 mm electromagnetic steel plate.

  FIG. 4 is an exploded perspective view showing the structure of a rotor 200A that can be employed as the rotor 200 in the direction of the rotation axis Q. 5 and 6 are perspective views showing the rotor 200A without being disassembled in the direction of the rotation axis Q, as viewed from the second stator 300 side and the first stator 100 side, respectively.

  The rotor 200 </ b> A includes a holder 24 that fixes the permanent magnet 22. The holder 24 is nonmagnetic, and is provided with a recess 241 that holds the permanent magnet 22 and a hole 240 into which a rotary shaft (not shown) is fitted. The recess 241 is illustrated here as a through hole. For example, the holder 24 is made of a nonmagnetic metal.

  By adopting such a holder 24, the magnetic poles can be positioned and the rotating shaft can be fixed to the rotor 200 without short-circuiting the magnetic flux between the magnetic poles.

  FIG. 7 is a cross-sectional view showing a first example of the positional relationship between the holder 24 and other members, and includes a rotating shaft 5 and shows a range corresponding to a substantial radius of the rotor 200. The cross-sectional position is a position where the magnetic plate 23 and the permanent magnet 22 exist. FIG. 8 is a perspective view showing the holder 24 employed in the structure shown in FIG.

  The holder 24 has a protrusion 24 a that narrows the recess 241 on the first stator 100 side of the recess 241. The magnetic body 21 is provided with a recess 21a that fits into the protrusion 24a. The fitting facilitates the positioning of the magnetic body 21 and the permanent magnet 22.

  The holder 24 and the magnetic plate 23 are preferably in close contact with each other. This is to increase the adhesion strength between the two. An adhesive may be used for the adhesion.

  However, in general, the adhesive has a high magnetic resistance. Therefore, it is desirable to provide a recess 24b on the surface of the magnetic plate 23 that is in close contact with the holder 24, and to provide an adhesive here. This is because the amount of adhesive necessary for the close contact between the holder 24 and the magnetic plate 23 can be reduced.

  FIG. 9 is a cross-sectional view showing a second example of the positional relationship between the holder 24 and other members, and the position shown is the same as FIG. FIG. 10 is a perspective view showing the holder 24 employed in the structure shown in FIG.

  In this example, the dimensions of the magnetic body 21 and the permanent magnet 22 in the direction perpendicular to the rotation axis Q are different, and a step is formed. The holder 24 is provided with a step 24c that fits the step. The fitting facilitates the positioning of the magnetic body 21 and the permanent magnet 22. In this example, the recess 24b shown in FIGS. 7 and 8 may be employed.

  FIG. 11 is a cross-sectional view showing a third example of the positional relationship between the holder 24 and other members, and the position shown is the same as FIG. In this example, in addition to the structure shown in FIG. 9, the holder 24 is further provided with a recess 24 d into which the magnetic plate 23 is fitted. This is preferable in that the magnetic plate 23 can be easily positioned.

  The holder 24 may be made of resin. Further, the magnetic body 21, the permanent magnet 22, and the magnetic plate 23 may be integrally molded with resin.

  FIG. 12 is a perspective view illustrating the configuration of a rotor 200B that can be employed as the rotor 200, and is shown exploded in the direction of the rotation axis Q. FIG. The magnetic plate 23 is configured by connecting its constituent members 231 in the circumferential direction. In FIG. 12, one component member 231 is shown separately, and the other component members are connected to form a portion 232. For example, the constituent member 231 is made of a dust core. The magnetic plate 23 is actually divided as many as the number of magnetic poles.

  As shown in the drawing, it is desirable that a circumferential end portion of the component member 231 has a concave portion 233 and a convex portion 234 in the circumferential direction. This is because the adjacent constituent members 231 can be easily positioned in the radial direction.

  When the magnetic plate 23 is configured by collecting a plurality of the constituent members 231 as described above, it is desirable to provide the holder 24 from the viewpoint of facilitating the positioning or increasing the mechanical strength.

  Further, it is desirable that the circumferential end portion of the component member 231 be positioned at the center of the magnetic pole of the rotor 200, here the center of the permanent magnet 22, when viewed along the rotation axis Q. Since the magnetic path for partially short-circuiting the field magnetic flux between the magnetic poles does not pass near the center of the permanent magnet 22, even if the circumferential end of the component member 231 is disposed here, the magnetic path It is because it does not inhibit the function of.

  FIG. 13 is a perspective view illustrating the configuration of a rotor 200 </ b> C that can be employed as the rotor 200, and is exploded in the direction of the rotation axis Q. However, unlike FIGS. 1, 4, and 12, the upper side of the drawing is the first stator 100 side, and the lower side of the drawing is the second stator 300 side.

  FIG. 14 is a cross-sectional view showing a part of a cross section of the rotor 200 </ b> C along the circumferential direction with respect to the rotation axis Q without being disassembled in the rotation axis Q direction. FIG. 15 is a cross-sectional view including and parallel to the rotation axis Q without being disassembled in the direction of the rotation axis Q, and shows a range substantially corresponding to the radius of the rotor 200C. FIG. 16 is a perspective view showing the appearance of a rotor 200C (rotating shaft 5 and push plate 26 described later are omitted) viewed from the first stator 100 side without being disassembled in the direction of the rotation axis Q.

  Returning to FIG. 13, the rotor 200 </ b> C includes magnetic bodies 25 that are alternately arranged with respect to the magnetic poles in the circumferential direction on the first stator 100 side with respect to the magnetic plate 23. The magnetic body 25 contributes to increasing so-called q-axis inductance and generating reluctance torque. The magnetic body 25 may be formed integrally with the magnetic plate 23.

  The position in the radial direction of the cross section shown in FIG. 14 is a position where the permanent magnet 22 and the magnetic body 25 exist. Here, the second example shown in FIG. 9 is adopted, and the magnetic body 21, the permanent magnet 22, and the magnetic plate 23 are arranged.

  The magnetic body 25 has a large portion 25a on the magnetic plate 23 side and a small portion 25b on the first stator 100 side. The recess 241 has a shape that fits into a step formed by the large portion 25a and the small portion 25b.

  Returning to FIG. 13, the holder 24 has an annular portion 242 on its inner peripheral side. The outer periphery of the annular portion 242 defines the inner periphery of the concave portion 241 of the holder 24. The annular portion 242 has a large diameter on the first stator 100 side and a small diameter on the third stator 300 side to form a step. In FIG. 13, in order to avoid complication, the step of the concave portion 241 is omitted except for the step of the annular portion 242.

  The rotary shaft 5 has a small-diameter portion 5a on the second stator 300 side and a large-diameter portion 5b on the first stator 100 side, and both are connected along the rotation axis Q. The small diameter portion 5 a is fitted into the holder 24, and the large diameter portion 5 b presses the magnetic body 21 from the first stator 100 side through the push plate 26. The push plate 26 is preferably nonmagnetic.

  The position of the cross section shown in FIG. 15 is a position where the permanent magnet 22 exists. A small diameter portion 5 a is fitted in the hole 240 of the holder 24 to hold the rotating shaft 5.

  The magnetic body 21 is fitted in the step of the annular portion 242 and is pressed by the pressing plate 26, and positioning in the direction along the rotation axis Q is performed.

  Of course, as shown in FIG. 7, the holder 24 may be provided with a recess 24 b and filled with an adhesive that bonds the holder 24 and the magnetic plate 23.

Second embodiment.
FIG. 17 is a perspective view showing a configuration of a rotor 200D according to the second embodiment of the present invention, which is disassembled along the rotation axis Q. FIG. The rotor 200D can also be used in place of the rotor 200 of the first embodiment. However, the rotor 200D does not use a permanent magnet and constitutes a so-called switched reluctance motor. FIG. 18 is a perspective view showing the appearance of the rotor 200D without being disassembled along the rotation axis Q. FIG.

  The rotor 200D has a configuration in which the permanent magnet 22 and the magnetic body 21 of the rotor 200A are replaced with a magnetic body 27, and the holder 24 is replaced with a holder 28, respectively. The magnetic body 27 functions as a magnetic pole of the rotor in the switched reluctance motor. The holder 28 is non-magnetic and has a through hole 280 that holds a rotating shaft (not shown) and a recess 281 into which the magnetic body 27 is fitted. Here, the case where the recessed part 281 has penetrated is illustrated.

  Also in the switched reluctance motor, when the first stator 100 is excited, the first thrust force works. Further, the magnetic flux flows into and out of the second stator 300 via the magnetic body 27 and the magnetic plate 23, and as a result, the second thrust force also works. Therefore, the magnetic plate 23 can partially short-circuit the magnetic flux flowing into and out of the magnetic body 27 from the first stator 100, and the magnetic body 27 can be short-circuited, and the same effect as in the first embodiment is achieved.

  The magnetic body 27 and the magnetic plate 23 can be integrally formed. For example, it is preferable to make them integrally with a dust core.

Fixing to the rotating electric machine frame.
FIG. 19 is a cross-sectional view showing a state in which the rotating electrical machine according to the present invention is fixed to the frame 6. Here, the case where the rotor 200A (FIG. 4) is employed is shown as an example, but the other rotor described above may be employed. FIG. 19 shows a cross section including and parallel to the rotation axis Q.

  The frame 6 has a hole 60 through which the rotary shaft 5 passes. The rotating shaft 5 is rotatably supported by a bearing 7 outside the frame 6 on the second stator 300 side. Since the rotating electric machine is an axial gap motor, the rotating shaft 5 can be short, and even if the rotating shaft 5 is supported by a cantilever structure, the influence of the rotating shaft 5 on the rotating electric machine is small.

  FIG. 19 illustrates the case where the rotating shaft 5 penetrates the first stator 100 and the frame 6. However, when the cantilever structure is adopted as described above, the rotation shaft 5 may not penetrate. . When the rotating shaft 5 does not penetrate the first stator 100, the connecting wire of the armature winding 13 can be provided on the inner peripheral side with respect to the magnetic core 12.

  In this case, it is not necessary to provide the hole 110 in the back yoke 11 of the first stator 100. However, it is preferable to use the hole 110 as a passage for pulling out the armature winding 13 instead of passing through the rotating shaft 5.

  A back yoke 11 and a stator magnetic plate 300 as a second stator are fixed to the inner wall of the frame 6 perpendicular to the rotation axis Q. For example, the frame 6 and the stator magnetic plate 300 (or the back yoke 11) are coupled by a bonding material such as an adhesive or a bolt.

  In this way, the frame 6 fixes the stator magnetic plate 300 on the side opposite to the rotor 200, whereby the mechanical strength of the stator magnetic plate 300 is reinforced. As described above, this is suitable for reducing the thickness of the stator magnetic plate 300.

Example of application to a compressor.
FIG. 20 is a cross-sectional view illustrating the configuration of a compressor using the rotating electrical machine according to the invention. FIG. 20 shows a cross section including the rotation axis Q and parallel thereto.

  FIG. 20 illustrates a so-called high pressure dome type compressor. Specifically, a suction pipe 92 for sucking refrigerant is provided on one surface of the sealed container 9, and a discharge pipe 93 for discharging the compressed refrigerant is provided on the other surface.

  Between the suction pipe 92 and the discharge pipe 93, a compression unit 91 that compresses the refrigerant is provided in the sealed container 9. In the sealed container 9, a rotary electric machine is provided on the discharge pipe 93 side with respect to the compression unit 91, and the compression unit 91 is driven by the rotary electric machine via the rotary shaft 5. An oil sump 94 is provided on the side opposite to the rotating electrical machine with respect to the compression unit 91, and a so-called vertical compressor is illustrated.

  The rotating electrical machine includes a first stator 100, a second stator 300, and a rotor 200A sandwiched between them. These configurations have been described above. However, although the case where the rotor 200A (FIG. 4) is employed is shown here as an example, the other rotor described above may be employed.

  The first stator 100 is fixed to the inner wall 90 of the sealed container 9. Here, a case where the rotating shaft 5 does not penetrate the first stator 100 is illustrated. However, as described above, a hole 110 is formed in the back yoke 10 in order to pull out the armature winding 13. In addition, although the refrigerant passage hole is not shown, it can be provided as necessary.

  In FIG. 20, the stator magnetic plate 300 as the second stator 300 is separated from the inner wall 90 of the hermetic container 9. If this is to be held on the inner wall of the hermetically sealed container 9, mechanical strength is required for the stator magnetic plate 300. Therefore, even when the stator magnetic plate 300 is formed of a wound iron core, it is preferable to harden it in a wound state or to fit it into another holder.

  Further, when the stator magnetic plate 300 is formed of a dust core, it can be easily attached directly to another structure. FIG. 20 illustrates the case where the stator magnetic plate 300 is fixed to the housing 91a of the compression portion 91 from the side opposite to the rotor 200A.

1 is a perspective view showing a rotating electrical machine according to a first embodiment of the present invention. It is sectional drawing which shows the rotary electric machine concerning 1st Embodiment of this invention. It is sectional drawing which expand | deploys and shows the cross section along the circumferential direction of a rotor. It is a perspective view which shows the structure of a rotor. It is a perspective view which shows a rotor. It is a perspective view which shows a rotor. It is sectional drawing which shows the 1st example of the positional relationship of a holder and another member. It is a perspective view which shows the holder employ | adopted with the structure shown by FIG. It is sectional drawing which shows the 2nd example of the positional relationship of a holder and another member. It is a perspective view which shows the holder employ | adopted with the structure shown by FIG. It is sectional drawing which shows the 3rd example of the positional relationship of a holder and another member. It is a perspective view which illustrates the composition of a rotor. It is a perspective view which illustrates the composition of a rotor. It is a perspective view which illustrates the composition of a rotor. It is sectional drawing which illustrates the structure of a rotor. It is a perspective view which illustrates the composition of a rotor. It is a perspective view which shows the structure of the rotor concerning 2nd Embodiment of this invention. It is a perspective view which shows the external appearance of a rotor. It is sectional drawing which shows the aspect which fixed the rotary electric machine concerning this invention to the frame. It is sectional drawing which illustrates the structure of the compressor using the rotary electric machine concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 1st stator 11 Back yoke 12 Magnetic core 13 Armature winding 200 Rotor 21, 25 Magnetic body 22 Permanent magnet 23 Magnetic plate 231 Steel plate 24 Holder 240 Hole 241, 24d Recessed part 300 2nd stator (Magnet for stator) Board)
5 Rotating shaft 6 Frame Q Rotating shaft

Claims (16)

A rotor (200) that rotates about a rotation axis (Q);
A first stator (100) facing the rotor along the rotation axis;
A second stator (300) facing the rotor on the opposite side of the first stator along the rotation axis;
The rotor is
A plurality of magnetic poles (22; 27) arranged along a circumferential direction with respect to the rotation axis;
A magnetic plate (23) provided on the magnetic pole on the second stator side, partially shorting the magnetic flux flowing into and out of the magnetic pole between the magnetic poles and partially flowing into and out of the second stator side; Have
The first stator is
A plurality of magnetic cores (12) opposed to the magnetic poles at an interval and arranged along the circumferential direction;
A plurality of armature windings (13) wound around at least one of the magnetic cores ;
A back yoke (11) for connecting the magnetic core on the side opposite to the rotor ,
The second stator is
Magnetic plate for stator (300) facing the magnetic plate with a gap
Have,
The thickness along the rotational axis of the stator magnetic plate (300) is smaller rotary electric machine than the thickness along the rotational axis of the back yoke.   The thickness of the magnetic plate for stator (300) along the rotation axis (Q) is greater than the thickness of the back yoke along the rotation axis of the magnetic plate (23) along the rotation axis. The rotating electrical machine according to claim 1, which is only small. A member (6) for fixing the stator magnetic plate (300) on the side opposite to the rotor (200)
The rotating electrical machine according to claim 1, further comprising:   The rotating electrical machine according to any one of claims 1 to 3, wherein the stator magnetic plate (300) is made of a dust core.   The rotating electrical machine according to any one of claims 1 to 3, wherein the stator magnetic plate (300) is a wound iron core in which a steel plate is wound around the rotating shaft (Q). The back yoke (11) is a laminated iron core in which steel plates are laminated along the rotation axis,
The rotating electrical machine according to claim 5, wherein a thickness of the steel sheet of the laminated core is larger than a thickness of the steel sheet of the wound core. The rotor (200)
Nonmagnetic holder (24) provided with a first recess (241) for holding the magnetic pole (12) and a hole (240) for fitting the rotating shaft (5).
The rotating electrical machine according to any one of claims 1 to 6, further comprising:   The rotating electrical machine according to claim 7, wherein the holder (24) and the magnetic plate (23) are in close contact with each other. A second recess (24b) is provided on the surface of the magnetic plate (23) in close contact with the holder (24),
The rotating electrical machine according to claim 8, wherein an adhesive is provided in the second recess.   The rotating electrical machine according to claim 8, wherein the holder (24) is provided with a second recess (24d) into which the magnetic plate (23) is fitted.   The rotating electrical machine according to any one of claims 1 to 10, wherein the magnetic plate (23) is formed by punching a single steel plate.   11. The magnetic plate (23) according to claim 1, wherein the magnetic plate (23) is a combination of steel plates (231) divided in the circumferential direction near the magnetic pole center of the rotor (200). Rotating electric machine.   The rotating electrical machine according to any one of claims 1 to 12, wherein the magnetic pole (22) is a permanent magnet. The rotor (200)
Magnetic body (21) provided on the first stator (100) side of the magnetic pole (22)
The rotating electrical machine according to claim 13, further comprising: The rotor (200)
Magnetic bodies (25) arranged alternately with respect to the magnetic poles in the circumferential direction on the first stator side with respect to the magnetic plate (23)
The rotating electrical machine according to any one of claims 13 to 14, further comprising:   The length along the rotation axis (Q) between the rotor (200) and the first stator (100), and the rotation axis between the rotor and the second stator (300). The rotating electrical machine according to any one of claims 1 to 15, wherein a length along the axis is equal.

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