JP2014027705A - Rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary machine that allows magnet magnetic flux to be appropriately varied while reducing restrictions on a configuration of a rotor and on a magnetic circuit.SOLUTION: In a rotary machine 10, a rotor 11 includes: a first rotor 21 and a second rotor 22 that face each other in a direction of a rotating shaft 20; a torque transmission section 24 that is switched between a torque transmission state in which rotary torque of the second rotor 22 is transmitted to the first rotor 21 and a torque non-transmission state; and a magnetic coupling section 23 that magnetically couples the second rotor 22 to a case 13. The first rotor 21 is fixed to the rotating shaft 20, and the second rotor 22 is not fixed to the rotating shaft 20. The second rotor 22 is magnetically coupled to the case 13 when current flowing through coils 12b is lower than a predetermined value, and is rotated when the current is at the predetermined value or higher. When the second rotor 22 is rotated, the torque transmission section 24 is switched to the torque transmission state.

Description

  The present invention relates to a rotating machine.

Conventionally, for example, a rotor consisting of an inner rotor and an outer rotor whose mutual rotation axes are arranged coaxially and whose relative phase can be changed has been provided, and the magnetic flux that contributes to the torque of the rotor can be changed according to the change in the relative phase An electric motor is known (see, for example, Patent Document 1).
Conventionally, for example, a rotating machine is known in which the rotor can be displaced in the axial direction with respect to the stator and the magnetic flux of the rotor linked to the stator can be changed in accordance with the change in the facing area between the rotor and the stator. (For example, refer to Patent Document 2).
Conventionally, for example, a rotating electrical machine that can change the magnetic flux of a rotor linked to a stator by performing magnetizing and demagnetizing by exciting the stator with respect to a rotor having a plurality of magnets having different magnetic characteristics. It is known (see, for example, Patent Document 3).

JP 2004-072978 A Japanese Patent No. 3844229 JP 2008-245368 A

By the way, in the electric motor which concerns on the said prior art, since a rotor is comprised by the several rotor of an inner rotor and an outer rotor, the problem that the magnet quantity required for a structure will increase arises. Further, it is necessary to set the magnet arrangement (that is, the magnetic circuit) of each rotor so as to generate a desired weak field and strong field, and the degree of freedom regarding the configuration of each rotor is reduced. Arise.
Further, in the rotating machine according to the above prior art, when the rotor is displaced in the axial direction with respect to the stator, a magnetic flux that is short-circuited from the surface of the rotor that does not face the stator in the radial direction to the stator core is generated. A problem arises when eddy current loss increases.
Further, in the rotating electrical machine according to the above-described prior art, it is necessary to set the arrangement of a plurality of magnets having different magnetic characteristics so that a desired field weakening and field strengthening are generated, and the configuration of each rotor There arises a problem that the degree of freedom is lowered.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a rotating machine capable of appropriately changing the magnetic flux of a magnet while suppressing restrictions on the configuration of the rotor and the magnetic circuit.

  In order to solve the above problems and achieve the object, a rotating machine according to the first aspect of the present invention includes a rotor (for example, the rotor 11 in the embodiment) and a stator core (for example, the stator core in the embodiment). 12a) a coil (for example, the coil 12b in the embodiment) wound with a coil (for example, the stator 12 in the embodiment), and a case for housing the rotor and the stator (for example, in the embodiment) The rotor 13 (for example, the rotating machine 10 in the embodiment), and the rotor is opposed to the rotating shaft (for example, the rotating shaft 20 in the embodiment) in the rotating shaft direction. The first rotor (for example, the first rotor 21 in the embodiment) and the second rotor (for example, the second rotor 22 in the embodiment) and the rotational torque of the second rotor arranged so as to Torque transmission means (for example, torque transmission unit 24 in the embodiment) capable of switching between a torque transmission state transmitted to one rotor and a torque non-transmission state in which the rotational torque of the second rotor is not transmitted to the first rotor; Magnetic coupling means (for example, magnetic coupling portion 23 in the embodiment) capable of magnetically coupling the second rotor to the case, and the first rotor is fixed to the rotating shaft, and the second rotor The rotor is not fixed to the rotating shaft, and when the current flowing through the coil is less than a predetermined value, the rotor is magnetically coupled to the case by the coupling means, and the current flowing through the coil is greater than or equal to the predetermined value And the torque transmitting means enters the torque transmitting state when the second rotor rotates.

  Further, in the rotating machine according to the second aspect of the present invention, the magnetic coupling means includes a rotor side coupling magnet (for example, the rotor side coupling magnet 61 in the embodiment) fixed to the second rotor, A case-side coupling magnet (for example, the case-side coupling magnet 62 in the embodiment) fixed to the case so as to face the rotor-side coupling magnet.

  Furthermore, in the rotating machine according to the third aspect of the present invention, the rotor side coupling magnet is fixed to an inner peripheral portion (for example, an inner peripheral surface 48A in the embodiment) of the second rotor, and the case side coupling is performed. The working magnet is fixed to the case so as to face the rotor-side coupling magnet in the radial direction of the second rotor.

  Furthermore, in the rotating machine according to the fourth aspect of the present invention, the torque transmission means is an excitation wound in the circumferential direction around the rotation axis in either one of the first rotor and the second rotor. A coil (for example, the exciting coil 71 in the embodiment), an inner peripheral portion (for example, the inner peripheral portion 72 in the embodiment) disposed on the inner peripheral side of the exciting coil in the one rotor, and the excitation An excitation side iron core portion (for example, an excitation side iron core portion 74 in the embodiment) having an outer circumference portion (for example, the outer circumference portion 73 in the embodiment) disposed on the outer circumference side of the coil, the first rotor, A nonmagnetic portion (for example, a nonmagnetic portion 75 in the embodiment) provided at a position facing the exciting coil in the rotation axis direction in the other rotor of the second rotor, and the other rotor Before An inner peripheral portion (for example, an inner peripheral portion 76 in the embodiment) disposed on the inner peripheral side of the nonmagnetic portion so as to be able to face the excitation side iron core portion in the rotation axis direction, and an outer peripheral side of the nonmagnetic portion Excited side core part (for example, excited side core part 78 in the embodiment) having an arranged outer peripheral part (for example, outer peripheral part 77 in the embodiment) and the excitation coil in a non-energized state. An energization switching unit (for example, an energization switching unit 79 in the embodiment) that can be switched to an energized state is provided.

  Furthermore, in the rotating machine according to the fifth aspect of the present invention, the first rotor and the second rotor have a plurality of magnetic pole portions arranged in the circumferential direction (for example, the magnet mounting portion 32, the magnet mounting portion in the embodiment). 42), and the plurality of magnetic pole portions are arranged so that the magnetization directions of the magnetic pole portions adjacent in the circumferential direction are reversed, and the outer peripheral portion of the exciting side iron core portion and the excited side iron core portion are The outer peripheral portion is opposed to each other in the rotation axis direction when the first rotor and the second rotor are arranged such that the magnetic pole portions having the same magnetization direction are opposed to each other in the rotation axis direction. And a protruding portion that protrudes so as to be close to each other in the rotational axis direction (for example, the protruding portion 73a and the protruding portion 77a in the embodiment).

  Furthermore, in the rotating machine according to the sixth aspect of the present invention, the stator core includes a first stator core (for example, the first stator core 91 in the embodiment) opposed to the first rotor in the radial direction, and the radial core in the radial direction. A second stator core (for example, the second stator core 92 in the embodiment) facing the second rotor, and a stator nonmagnetic portion (between the first stator core and the second stator core in the rotation axis direction) ( For example, the stator nonmagnetic part 93) in the embodiment is provided.

  According to the rotating machine according to the first aspect of the present invention, only the rotational torque generated when the magnetic flux of the first rotor is linked to the stator is transmitted to the rotating shaft (weakening field state), The state (strong field state) in which the rotational torque generated when the magnetic fluxes of the first and second rotors are linked to the stator is transmitted to the rotating shaft easily and appropriately according to the current flowing through the coil. Can be switched. This prevents, for example, the necessity of restricting the magnet arrangement (that is, the magnetic circuit) of each rotor in order to enable switching between the weak field state and the strong field state, and the degree of freedom regarding the configuration of each rotor. It can prevent that it falls.

  According to the rotating machine according to the second aspect of the present invention, the second rotor can be magnetically coupled to the case by the attractive force generated by the magnetic force between the opposing rotor-side coupling magnet and the case-side coupling magnet. Therefore, it is possible to prevent the configuration of the magnetic coupling means from becoming complicated.

  The rotating machine according to the third aspect of the present invention can prevent the axial dimension of the rotating machine from increasing.

According to the rotating machine of the fourth aspect of the present invention, the excited side iron core is magnetized by the magnetic flux generated in the exciting iron core in the energized state of the exciting coil, and the exciting side iron core and the excited iron core are Due to the magnetic attraction force between them, one rotor and the other rotor are coupled in a non-contact manner, and torque transmission is possible.
That is, the torque transmission means can switch between the torque transmission state and the torque non-transmission state while maintaining one rotor and the other rotor in a non-contact state, and the second rotor is the first rotor in the torque non-transmission state. It becomes possible to prevent a load from being generated (a drag loss is generated).

According to the rotating machine according to the fifth aspect of the present invention, the protrusion provided on the outer peripheral portion of the excitation-side iron core portion of the first rotor and the protrusion provided on the outer peripheral portion of the excited-side iron core portion of the second rotor. And a magnetic path is formed by the inner peripheral portions of the first rotor and the second rotor, and the magnetic pole portions having the same magnetization direction are opposed to each other in the rotation axis direction. The outer periphery of the second rotor is coupled in a non-contact manner by a magnetic attractive force. Thus, the first rotor and the second rotor can be set to the same phase in the torque transmission state, and the rotational torque of the second rotor can be efficiently transmitted to the first rotor.
Moreover, by providing the protrusions on the respective outer peripheral portions, for example, the same phase can be set with higher accuracy than when the protrusions are provided on the respective inner peripheral portions.

  According to the rotating machine of the sixth aspect of the present invention, between each stator core and each rotor that are not opposed in the radial direction (that is, between the first stator core and the second rotor, and between the second stator core and the first rotor). ) Can be prevented, and an increase in eddy current loss in each stator core can be prevented.

It is a perspective view which fractures | ruptures and shows the rotary machine which concerns on embodiment of this invention in parallel with a rotating shaft direction. It is sectional drawing which fractured | ruptured the rotary machine which concerns on embodiment of this invention in parallel with the rotating shaft direction. It is the top view which looked at the 1st rotor of the rotary machine which concerns on embodiment of this invention from the rotating shaft direction, Comprising: It is the AA arrow line view shown in FIG. It is a perspective view of the 1st rotor of the rotary machine which concerns on embodiment of this invention. It is the top view which looked at the 2nd rotor of the rotary machine which concerns on embodiment of this invention from the rotating shaft direction, Comprising: It is the BB arrow line view shown in FIG. It is a perspective view of the 2nd rotor of the rotary machine which concerns on embodiment of this invention. It is the top view which looked at the 2nd rotor of the rotary machine which concerns on embodiment of this invention from the Z direction of the rotating shaft direction shown in FIG. It is a flowchart which shows operation | movement of the rotary machine which concerns on embodiment of this invention. It is sectional drawing which fractured | ruptured a part of rotary machine which concerns on embodiment of this invention in parallel with the rotating shaft direction.

Hereinafter, an embodiment of a rotating machine of the present invention will be described with reference to the accompanying drawings.
1 to 7, for example, the rotating machine 10 according to this embodiment accommodates a rotor 11, a stator 12 in which a three-phase coil 12b is wound around a stator core 12a, and the rotor 11 and the stator 12. A case 13 is provided.

  The rotating machine 10 is, for example, an inner rotor type brushless DC motor. The rotor 11 is disposed on the inner peripheral side of the annular stator 12, and the outer peripheral portion of the stator core 12 a of the stator 12 is fixed to the case 13.

  The rotor 11 includes a rotating shaft 20, a first rotor 21 and a second rotor 22 that are arranged in a non-contact manner so as to face each other in the rotating shaft direction, and a magnetic coupling that can magnetically couple the second rotor 22 to the case 13. Part 23 and a torque transmission unit capable of switching between a torque transmission state in which the rotational torque of the second rotor 22 is transmitted to the first rotor 21 and a torque non-transmission state in which the rotational torque of the second rotor 22 is not transmitted to the first rotor 21. 24.

  The first rotor 21 is fixed to the rotary shaft 20, and a first rotor core 31 and permanent magnets 33 mounted on a plurality of magnet mounting portions 32 formed at positions offset toward the outer peripheral side of the first rotor core 31. It has.

The plurality of magnet mounting portions 32 are arranged at equal intervals in the circumferential direction, and each magnet mounting portion 32 includes a pair of magnet mounting slots 32a and 32a adjacent in the circumferential direction.
Two plate-like permanent magnets 33, 33 magnetized in the same thickness direction are mounted in the pair of magnet mounting slots 32a, 32a.

In the magnet mounting portions 32 and 32 adjacent to each other in the circumferential direction, the direction of the magnetic poles of the permanent magnet 33 is set to be opposite.
That is, a pair of magnet mounting slots 32a and 32a in which a pair of permanent magnets 33 and 33 having an N pole on the outer peripheral side are mounted, and a pair of permanent magnets 33 and 33 in which an outer side is set to an S pole are mounted. A pair of magnet mounting slots 32a and 32a are alternately arranged in the circumferential direction.

The second rotor 22 is not fixed to the rotating shaft 20 and is rotatably supported by the case 13 via the bearing 40, and is biased toward the second rotor core 41 and the outer peripheral side of the second rotor core 41. And a permanent magnet 43 mounted on the plurality of formed magnet mounting portions 42.
ing.

  Further, the second rotor core 41 includes a through hole 45 into which the rotation shaft 20 is inserted in a non-contact manner at the center, a concave groove 46 formed at the end opposite to the first rotor 21 in the rotation axis direction, and a first groove. A first protrusion 47 and a second protrusion 48 are provided.

The concave groove 46 is formed in an annular shape so as to surround the through hole 45 from the outer peripheral side.
The first projecting portion 47 has an inner peripheral surface 47A that is continuous with the inner wall surface 45A of the through hole 45 and an outer peripheral surface 47B that is continuous with the inner peripheral wall surface 46A of the groove 46, and protrudes in the rotation axis direction. It is formed in a shape.
The second projecting portion 48 is formed in a cylindrical shape projecting in the rotation axis direction so as to surround the first projecting portion 47 from the outer peripheral side, and has an inner peripheral surface 48 </ b> A continuous with the outer peripheral side wall surface 46 </ b> B of the groove 46. ing.

A cylindrical support that forms a part of the case 13 is formed in the concave groove 46 and an annular space 49 formed so as to be sandwiched by the first protrusion 47 and the second protrusion 48 from both sides in the radial direction. Part 50 is inserted.
An annular bearing 40 is mounted between the inner peripheral surface 50A of the cylindrical support portion 50 and the outer peripheral surface 47B of the first protrusion 47, and the cylindrical support portion 50 is connected to the first support portion 50 by the bearing 40. One protrusion 47 (that is, the second rotor 22) is supported so as to be rotatable around the rotation shaft 20.

The plurality of magnet mounting portions 42 are arranged at equal intervals in the circumferential direction, and each magnet mounting portion 42 includes a pair of magnet mounting slots 42a and 42a adjacent in the circumferential direction.
Two flat permanent magnets 43 and 43 magnetized in the same thickness direction are mounted in the pair of magnet mounting slots 42a and 42a.

In the magnet mounting portions 42 and 42 adjacent in the circumferential direction, the direction of the magnetic pole of the permanent magnet 43 is set to be opposite.
That is, a pair of magnet mounting slots 42a and 42a in which a pair of permanent magnets 43 and 43 having an N pole on the outer peripheral side are mounted, and a pair of permanent magnets 43 and 43 in which an outer peripheral side is an S pole are mounted. In addition, a pair of magnet mounting slots 42a and 42a are alternately arranged in the circumferential direction.

  In addition, the arrangement positions of the plurality of magnet mounting portions 32 and the permanent magnets 33 in the first rotor 21 in the radial direction and the circumferential direction, and the radial direction and the circumferential direction of the plurality of magnet mounting portions 42 and the permanent magnets 43 in the second rotor 22. The permanent magnets 33 and 43 having the same magnetic pole direction and the same magnetic pole direction can be opposed to each other in the rotation axis direction.

  The magnetic coupling unit 23 includes a rotor side coupling magnet 61 fixed to the second rotor 22 and a case side coupling magnet 62 fixed to the case 13 so as to face the rotor side coupling magnet 61. Yes.

The rotor-side coupling magnet 61 is, for example, a flat plate magnetized in the thickness direction, and the magnetizing direction is a radial direction, and the rotor-side coupling magnet 61 is on the inner peripheral surface 48A of the second protrusion 48 of the second rotor 22. The cylindrical support part 50 constituting a part of the case 13 is fixed to a position facing the outer peripheral surface 50B in the radial direction.
The case-side coupling magnet 62 is, for example, a flat plate that is magnetized in the thickness direction, the magnetization direction is a radial direction, and the rotor-side coupling magnet 61 is opposed to the rotor-side coupling magnet 61 in the radial direction. 13 is fixed to a position facing the inner peripheral surface 48 </ b> A of the second projecting portion 48 of the second rotor 22 in the radial direction on the outer peripheral surface 50 </ b> B of the cylindrical support portion 50 that forms a part of 13.

  The rotor-side coupling magnet 61 and the case-side coupling magnet 62 are disposed so as to be able to face each other in the radial direction with their magnetization directions being opposite to each other, and face each other at a predetermined rotational position of the second rotor 22 with respect to the case 13. The attraction force by the magnetic force acts between the rotor side coupling magnet 61 and the case side coupling magnet 62.

The attraction force due to the magnetic force acting between the opposing rotor-side coupling magnet 61 and the case-side coupling magnet 62 is the rotation of the second rotor 22 when the current flowing through the coil 12b of the stator 12 is less than a predetermined value. It is set to have a magnitude that allows the rotation of the second rotor 22 to be maintained when the stop is maintained and the current flowing through the coil 12b of the stator 12 is greater than or equal to a predetermined value.
That is, the magnetic coupling portion 23 including the rotor-side coupling magnet 61 and the case-side coupling magnet 62 has a predetermined rotational torque generated in the second rotor 22 by the magnetic flux generated from the coil 12b of the stator 12. When the rotation is smaller than the magnitude, the rotation stop of the second rotor 22 is maintained, and when the magnitude of the rotational torque generated in the second rotor 22 by the magnetic flux generated from the coil 12b of the stator 12 is a predetermined magnitude or more, the second A torque limit function for rotating the rotor 22 is provided.

  The torque transmission unit 24 includes an excitation coil 71 wound around the rotation axis 20 in the second rotor core 41 in the circumferential direction, an inner peripheral portion 72 disposed on the inner peripheral side of the excitation coil 71 in the second rotor core 41, and excitation. An excitation-side iron core portion 74 having an outer peripheral portion 73 disposed on the outer peripheral side of the coil 71, and an annular nonmagnetic portion 75 provided at a position facing the excitation coil 71 in the rotation axis direction in the first rotor core 31. In the first rotor core 31, an excited side iron core portion 78 including an inner peripheral portion 76 disposed on the inner peripheral side of the nonmagnetic portion 75 and an outer peripheral portion 77 disposed on the outer peripheral side of the nonmagnetic portion 75, an excitation coil It is even configured to include an energization switching unit 79 that can switch 71 between an energized state and a non-energized state.

The inner peripheral portion 72 of the exciting side iron core portion 74 and the inner peripheral portion 76 of the excited side iron core portion 78 are formed in a coaxial cylindrical shape surrounding the rotating shaft 20 from the outer peripheral side, and end surfaces 72A and 76A in the direction of the respective rotating shafts. Projecting in the direction of the rotation axis.
The outer peripheral portion 73 of the exciting side iron core portion 74 and the outer peripheral portion 77 of the excited side iron core portion 78 are formed in a coaxial cylindrical shape, and end surfaces 73A and 77A in the rotation axis direction face each other. Protrusions 73a and 77a projecting from the predetermined circumferential positions on the end faces 73A and 77A so as to be close to each other in the rotation axis direction are provided.

  The predetermined positions in the circumferential direction at which the protrusions 73a and 77a are provided are magnetic pole portions having the same magnetization direction in the first rotor 21 and the second rotor 22 (that is, the magnet of the first rotor 21 to which the permanent magnet 33 is attached). When the first rotor 21 and the second rotor 22 are arranged so that the mounting portion 32 and the magnet mounting portion 42 of the second rotor 22 to which the permanent magnet 43 is mounted face each other in the rotation axis direction, the rotation shaft The positions are opposed to each other in the direction (for example, positions that are radially inward from the magnetic pole portions having the same magnetization direction and are opposed to each other in the rotation axis direction).

  For example, in the rotating machine 10 shown in FIGS. 3 to 6, the plurality of protrusions 73 a of the excitation-side iron core portion 74 includes a plurality of second rotors 22 each having a permanent magnet 43 having an N pole on the outer peripheral side and an S pole on the inner peripheral side. The magnet mounting portions 42 are arranged at positions radially inward from the magnet mounting portions 42 at the same circumferential angular intervals as the circumferential angular intervals of the magnet mounting portions 42. Similarly, the plurality of projecting portions 77a of the excited side iron core portion 78 are arranged in the circumferential direction of the plurality of magnet mounting portions 32 of the first rotor 21 to which the permanent magnet 33 having the N pole on the outer peripheral side and the S pole on the inner peripheral side is mounted. It is arranged at a position that is radially inward from each magnet mounting portion 32 at the same circumferential angular interval as the angular interval, and is opposed to the plurality of protrusions 73a of the excitation-side iron core portion 74 in the rotational axis direction.

  In the energized state of the exciting coil 71, a magnetic path is formed by the projecting portion 73a and the projecting portion 77a facing each other in the rotation axis direction, and the inner circumferential portion 72 and the inner circumferential portion 76 facing each other in the rotation axis direction. The excited side core portion 78 is magnetized by the magnetic flux generated in the side core portion 74, and a magnetic attraction force is generated between the excitation side core portion 74 and the excited side core portion 78. As a result, the first rotor 21 and the second rotor 22 are coupled in a non-contact manner, and a torque transmission state is established in which the rotational torque of the second rotor can be transmitted to the first rotor 21. Moreover, in this torque transmission state, the first rotor 21 and the second rotor 22 are in the same phase.

  In each of the exciting side iron core portion 74 and the excited side iron core portion 78, the circumferential interval between the plurality of projecting portions 73a and the circumferential interval between the plurality of projecting portions 77a are made constant so that the rotational torque is periodically generated. Generation of pulsation can be suppressed. Furthermore, by setting the number of each of the plurality of protrusions 73a and the plurality of protrusions 77a to a value different from the multiple of the number of poles of the magnetic pole portions of each of the first rotor 21 and the second rotor 22, each first In the rotor 21 and the second rotor 22, it is possible to prevent the first rotor 21 and the second rotor 22 from being coupled in a non-contact manner in a state where the magnetic pole portions having opposite magnetization directions face each other in the rotation axis direction. it can.

The operation of the energization switching unit 79 that can switch the excitation coil 71 between an energized state and a non-energized state is controlled by a control device 81 as shown in FIG. 6, for example.
The control device 81 determines whether the excitation coil 71 is energized based on the rotational speed of the rotating machine 10 detected or estimated by a rotational speed sensor (not shown) or the like, and a torque command indicating the torque required for the rotating machine 10. And switching between the non-energized state.

  For example, the controller 81 previously determines the rotational speed, torque, and operating efficiency of the rotating machine 10 with respect to the energized state (that is, the torque transmission state) and the non-energized state (that is, the torque non-transmitted state) of the excitation coil 71. And stores data such as a map indicating a predetermined correspondence relationship with the operating state of the rotating machine 10 (for example, a state where priority is given to operating efficiency, a state where priority is given to maximum torque, and a state where priority is given to maximum rotation speed) Or the like) is instructed to switch the excitation coil 71 between the energized state and the non-energized state.

Note that the control device 81 determines that the energization state (that is, the torque transmission state) of the excitation coil 71 is a state where at least the second rotor 22 can rotate against the attractive force of the magnetic coupling portion 23 (that is, the coil of the stator 12). The current flowing through 12b is preferably set to a state equal to or greater than a predetermined value. For example, control is performed so that the excitation coil 71 is energized (that is, the torque transmission state) when the second rotor 22 rotates.
The control device 81 controls the operation state of the rotating machine 10 by controlling the operation of the inverter 82 that energizes the three-phase coil 12b of the rotating machine 10.

  The stator core 12a of the stator 12 includes a first stator core 91 that faces the first rotor core 31 in the radial direction, a second stator core 92 that faces the second rotor core 41 in the radial direction, and the first stator core 91 and the second stator in the rotational axis direction. A stator nonmagnetic portion 93 made of a nonmagnetic member is provided between the stator core 92 and the stator core 92.

  The rotating machine 10 according to this embodiment has the above-described configuration. Next, the operation of the rotating machine 10 will be described.

First, in step S01 shown in FIG. 8, for example, the rotation speed of the rotating machine 10 is acquired by detection or estimation using a rotation speed sensor (not shown), for example.
Next, in step S02, a torque command for the torque of the rotating machine 10 is acquired.
Next, in step S03, based on the rotation speed of the rotating machine 10 and the torque command, it is determined whether or not the energization state of the excitation coil 71 (that is, the torque transmission state) is necessary.
If this determination is “NO”, the flow proceeds to step S 04, and in this step S 04, the exciting coil 71 is set in a non-energized state (ie, torque non-transmitting state) and the flow proceeds to the end.
On the other hand, if this determination is “YES”, the flow proceeds to step S 05, and in this step S 05, the excitation coil 71 is energized (ie, torque transmission state) and the flow proceeds to the end.

For example, as shown in FIG. 9A, when the rotating machine 10 is under a low load and the current flowing through the coil 12b of the stator 12 is in a low excitation state where the current is less than a predetermined value, the second rotor 22 has a magnetic coupling portion 23. Thus, the stationary state is maintained, the excitation coil 71 is set in a non-energized state (that is, a torque non-transmission state), and only the rotational torque of the first rotor 21 is transmitted to the rotary shaft 20.
In this case, a field weakening state in which the amount of magnet magnetic flux that contributes to the rotational torque of the rotating shaft 20 is reduced.

On the other hand, as shown in FIG. 9B, for example, when the rotating machine 10 is under a high load and the current flowing through the coil 12b of the stator 12 is in a high excitation state with a predetermined value or more, the second rotor 22 is magnetically coupled. Rotating against the attractive force of the portion 23, the energizing state of the exciting coil 71 (that is, the torque transmitting state) is set, and the rotating torque of the first rotor 21 and the rotating torque of the second rotor are applied to the rotating shaft 20. Communicated.
In this case, a strong field state in which the amount of magnet magnetic flux contributing to the rotational torque of the rotating shaft 20 is increased is obtained.

  As described above, according to the rotating machine 10 according to the embodiment of the present invention, only the rotational torque generated when the magnetic flux of the first rotor 21 is linked to the stator 12 is transmitted to the rotating shaft 20 (weakening). Field state) and a state in which the rotational torque generated by the linkage of the magnetic fluxes of the first rotor 21 and the second rotor 22 to the stator 12 is transmitted to the rotating shaft 20 (strong field state). Switching can be easily and appropriately performed according to the current flowing in the coil 12b of the stator 12. Thus, for example, it is possible to prevent the magnet arrangement (that is, the magnetic circuit) of each of the rotors 21 and 22 from being restricted in order to enable switching between the weak field state and the strong field state. It is possible to prevent the degree of freedom related to the configuration from decreasing.

  Further, the second rotor 22 can be magnetically coupled to the case 13 by the attractive force generated by the magnetic force between the rotor-side coupling magnet 61 and the case-side coupling magnet 62 that are opposed in the radial direction. Compared with the case where the rotor side coupling magnet 61 and the case side coupling magnet 62 are arranged so as to face each other in the rotation axis direction, for example, the configuration of the rotating machine 10 can be prevented. An increase in the axial dimension can be prevented.

  Further, the torque transmission unit 24 can switch between a torque transmission state and a torque non-transmission state while maintaining the first rotor 21 and the second rotor 22 in a non-contact state, and the second rotor 22 in the torque non-transmission state. Can be prevented from becoming a load with respect to the rotation of the first rotor 21 (the occurrence of drag loss).

  Further, a non-magnetic portion 75 is provided at a position facing the exciting coil 71 in the rotation axis direction, and each protrusion 73a, By providing 77a, the first rotor 21 and the second rotor 22 can be accurately set to the same phase in the torque transmission state, and the rotational torque of the second rotor 22 can be efficiently transmitted to the first rotor 21. Can do.

Furthermore, by providing the stator nonmagnetic portion 93, between the first stator core 91 and the second rotor core 41 that are not opposed in the radial direction, and between the second stator core 92 and the first rotor core 31 that are not opposed in the radial direction. It is possible to prevent occurrence of magnetic flux that is short-circuited, and to prevent increase in eddy current loss in each of the stator cores 91 and 92.
Further, it is possible to prevent a magnetic flux that is short-circuited from the first rotor core 31 through the first stator core 91 and the second stator core 92 to the second rotor core 41, and to prevent an increase in eddy current loss in each of the stator cores 91 and 92. Can do.

  In the above-described embodiment, the rotor-side coupling magnet 61 and the case-side coupling magnet 62 of the magnetic coupling portion 23 are arranged to face each other in a direction other than the radial direction (for example, the rotation axis direction). May be.

  In the above-described embodiment, the first rotor core 31 may be provided with the exciting coil 71 and the second rotor core 41 may be provided with the nonmagnetic portion 75.

In the above-described embodiment, the projecting portions 73a and 77a are arranged radially inward from the magnet mounting portions 42 and 32. However, the present invention is not limited to this. For example, the magnet mounting portions 42 and 32 are provided. May be arranged at the radially outward side, for example, at a radial position equal to the magnet mounting portions 42 and 32, for example.
In the embodiment described above, the magnetic pole portions having the same magnetization direction are the magnet mounting portions 42 and 32 to which the permanent magnets 43 and 33 having the N pole on the outer peripheral side and the S pole on the inner peripheral side are mounted. However, the present invention is not limited to this. For example, the magnet mounting portions 42 and 32 on which the permanent magnets 43 and 33 having the S pole on the outer peripheral side and the N pole on the inner peripheral side are mounted.
In short, the protrusions 73a and 77a are mutually in the rotation axis direction when the first rotor 21 and the second rotor 22 are arranged so that the magnetic pole portions having the same magnetization direction face each other in the rotation axis direction. What is necessary is just to arrange | position in the suitable position which opposes.
In the above-described embodiment, the protrusions 73a and 77a are provided on the outer peripheral portion 73 of the exciting side core portion 74 and the outer peripheral portion 77 of the excited side core portion 78. However, the present invention is not limited to this. Protruding portions that protrude so as to be close to each other in the rotation axis direction may be provided on the inner peripheral portion 72 of the exciting side iron core portion 74 and the inner peripheral portion 76 of the excited side iron core portion 78.

  In the above-described embodiment, the control device 81 allows the second rotor 22 to rotate against the attractive force of the magnetic coupling portion 23 because the current flowing through the coil 12b of the stator 12 becomes a predetermined value or more. However, the present invention is not limited to this. For example, the current flowing through the coil 12b of the stator 12 is a predetermined value close to a predetermined value. When the magnetic flux generated from the coil 12b of the stator 12 approaches the magnitude of the magnetic flux at which the second rotor 22 starts to rotate by a predetermined degree, the excitation coil 71 is energized (that is, torque transmission). State).

In this case, the second rotor 22 is magnetically applied to the rotational torque generated in the second rotor 22 by the magnetic flux generated from the coil 12 b of the stator 12 and the first rotor 21 in which the second rotor 22 is rotated by the torque transmission unit 24. Due to the rotational torque generated in the second rotor 22 by being attracted, it can rotate against the attractive force of the magnetic coupling portion 23.
Thereby, for example, even when a solid difference in the attractive force of the magnetic coupling portion 23 or a change in the attractive force due to temperature occurs, the rotation start timing of the second rotor 22 and the rotational torque of the second rotor 22 are reduced. The start timing of the torque transmission state transmitted to the first rotor 21 can be controlled with higher accuracy.

At this time, the magnetic coupling portion 23 including the rotor-side coupling magnet 61 and the case-side coupling magnet 62 has a torque limit function.
This torque limit function is magnetically attracted to the rotational torque generated in the second rotor 22 by the magnetic flux generated from the coil 12 b of the stator 12 and the first rotor 21 in which the second rotor 22 rotates by the torque transmission unit 24. When the total torque including the rotational torque generated in the second rotor 22 is smaller than a predetermined magnitude, the rotation stop of the second rotor 22 is maintained. Further, the second rotor 22 is magnetically attracted to the first rotor 21 rotated by the torque transmission unit 24 and the rotational torque generated in the second rotor 22 by the magnetic flux generated from the coil 12 b of the stator 12. The second rotor 22 is rotated when the total torque with the rotational torque generated at the time is greater than or equal to a predetermined magnitude.

DESCRIPTION OF SYMBOLS 10 Rotating machine 11 Rotor 12 Stator 12a Stator core 12b Coil 13 Case 21 First rotor 22 Second rotor 23 Torque transmission means (magnetic coupling means)
24 Torque transmission part (torque transmission means)
32 Magnet mounting part (magnetic pole part)
42 Magnet mounting part (magnetic pole part)
48A Inner circumference (inner circumference)
61 Rotor side coupling magnet (rotor side coupling magnet)
62 Case side coupling magnet (Case side coupling magnet)
71 Excitation coil 72 Inner peripheral part 73 Outer peripheral part 73a Protrusion part 74 Excitation side iron core part 75 Nonmagnetic part 76 Inner peripheral part 77 Outer peripheral part 77a Protrusion part 78 Excited side iron core part 79 Energization switching part (energization switching means)
91 1st stator core 92 2nd stator core 93 Stator nonmagnetic part

Claims (6)

A rotating machine comprising a rotor, a stator having a coil wound around a stator core, and a case for housing the rotor and the stator,
The rotor includes a rotation shaft, a first rotor and a second rotor arranged so as to face each other in the rotation axis direction, a torque transmission state for transmitting a rotation torque of the second rotor to the first rotor, and the second rotor. Torque transmitting means capable of switching between a torque non-transmitting state in which the rotational torque of the rotor is not transmitted to the first rotor;
Magnetic coupling means capable of magnetically coupling the second rotor to the case;
The first rotor is fixed to the rotating shaft;
The second rotor is not fixed to the rotating shaft, and when the current flowing through the coil is less than a predetermined value, the second rotor is magnetically coupled to the case by the coupling means, and the current flowing through the coil is the predetermined value. If it is above, it will rotate,
The rotating machine according to claim 1, wherein the torque transmitting means is in the torque transmitting state when the second rotor rotates. The magnetic coupling means includes a rotor-side coupling magnet fixed to the second rotor and a case-side coupling magnet fixed to the case so as to face the rotor-side coupling magnet. The rotating machine according to claim 1. The rotor-side coupling magnet is fixed to the inner periphery of the second rotor, and the case-side coupling magnet is disposed on the case so as to face the rotor-side coupling magnet in the radial direction of the second rotor. The rotating machine according to claim 2, wherein the rotating machine is fixed. The torque transmission means includes an exciting coil wound in a circumferential direction around the rotation axis in one of the first rotor and the second rotor;
An excitation side iron core portion comprising an inner peripheral portion disposed on the inner peripheral side of the excitation coil and an outer peripheral portion disposed on the outer peripheral side of the excitation coil in the one rotor;
A nonmagnetic portion provided at a position facing the excitation coil in the direction of the rotation axis in the other rotor of the first rotor and the second rotor;
The other rotor includes an inner peripheral portion disposed on the inner peripheral side of the nonmagnetic portion and an outer peripheral portion disposed on the outer peripheral side of the nonmagnetic portion so as to be able to face the excitation side iron core portion in the rotation axis direction. To be excited side iron core,
The rotating machine according to any one of claims 1 to 3, further comprising energization switching means capable of switching the excitation coil between an energized state and a non-energized state. The first rotor and the second rotor include a plurality of magnetic pole portions arranged in a circumferential direction, and the plurality of magnetic pole portions are arranged so that magnetization directions of the magnetic pole portions adjacent in the circumferential direction are reversed,
The first rotor is configured such that the outer peripheral portion of the excitation-side iron core portion and the outer peripheral portion of the excited-side iron core portion are opposed to each other in the rotation axis direction with the magnetic pole portions having the same magnetization direction. 5. The apparatus according to claim 4, further comprising a projecting portion that projects so as to be close to each other in the rotation axis direction at a position facing each other in the rotation axis direction when the second rotor is disposed. Rotating machine. The stator core includes a first stator core that faces the first rotor in a radial direction, a second stator core that faces the second rotor in a radial direction, and the first stator core and the second stator core in the rotation axis direction. The rotating machine according to any one of claims 1 to 5, further comprising a stator nonmagnetic portion disposed therebetween.

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