Rotating Electric Machine

Abstract

To improve the efficiency while suppressing the induced voltage at high rotation.SOLUTION: A rotary electric machine 1 that includes a rotor 2 and a stator 4, in which a second permanent magnet 12 is arranged on the rotor 2 includes a movable mechanism 10 that changes magnet magnetic flux to the stator 4 by moving the second permanent magnet 12 according to the rotation speed of the rotor 2.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a rotating electric machine. [Background technology]

[0002] Patent Document 1 discloses a rotating electric machine with a magnetic flux variable mechanism. This rotating electric machine is equipped with a magnetic flux variable mechanism on the axial end face of the rotor core. The magnetic flux variable mechanism uses centrifugal force to bring the magnetic flux short-circuit material closer to the permanent magnet, and reduces the magnetic flux interlinked with the stator coil when the rotor rotates at a high rotation speed. As a result, the back electromotive voltage generated by the interlinked magnetic flux is prevented from becoming excessive. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-97359 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a rotating electric machine with a magnet arranged in the rotor, an induced voltage is generated in the stator coil as the rotor rotates inside the stator. The induced voltage increases as the rotor rotation speed increases. For this reason, it is common to suppress the induced voltage by passing a field weakening current through the stator coil. However, passing a field weakening current increases copper loss, which may reduce the efficiency of the rotating electric machine.

[0005] The present invention has been made in view of the above problems, and has an object to suppress the induced voltage during high speed rotation and improve efficiency. [Means for solving the problem]

[0006] The present invention byA rotating electric machine has a rotor and a stator, with a magnet arranged on the rotor, and has a movable mechanism that changes the magnetic flux of the magnet to the stator by moving the magnet in accordance with the rotational speed of the rotor. A movable mechanism according to one aspect of the present invention is a mechanism for reducing the magnetic flux to the stator by moving the magnet away from the stator, and includes a weight that moves the magnet by centrifugal force, and a housing frame that is assembled to the rotor by being pushed into an insertion hole provided in the rotor. The weights are provided on both sides of the magnet in the circumferential direction, and each have opposing inclined surfaces that extend obliquely radially outward from both sides of the magnet in the circumferential direction toward the center when viewed along the axial direction. The movable mechanism further includes support members that are connected to the magnet and come into contact with each opposing inclined surface when the magnet is in its original position. A movable mechanism according to another aspect of the present invention is a mechanism for reducing the magnetic flux to the stator by moving the magnet in a direction away from the stator, and includes a weight that moves the magnet by centrifugal force. The rotor includes a plurality of magnets per magnetic pole. The magnet is disposed on the q-axis located at the boundary between adjacent magnetic poles in the circumferential direction formed on the rotor by the plurality of magnets, and moves along the radial direction. Effect of the Invention

[0007] According to this aspect, the magnet flux to the stator can be changed by, for example, changing the distance between the magnet and the stator by moving the magnet with the movable mechanism according to the rotation speed of the rotor. Therefore, by moving the magnet with the movable mechanism, it is possible to reduce the interlinkage flux to the stator at high rotation speeds and suppress the induced voltage. In addition, since the field weakening current can be suppressed by the amount of the suppression of the induced voltage, copper loss can be reduced, and this makes it possible to improve the efficiency of the rotating electric machine. Furthermore, since the movable mechanism moves the magnet arranged in the rotor, the reduction range of the interlinkage flux is not concentrated at the axial end of the rotating electric machine as in the case where a magnetic flux variable mechanism is provided on the axial end face of the rotor core, and the axial length of the rotating electric machine is not lengthened. In addition, since the interlinkage flux to the stator can be increased by returning the magnet to its original position with the movable mechanism at low rotation speeds, it is possible to ensure torque at low rotation speeds. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a diagram showing a main part of a rotating electric machine. [Figure 2A] 11A and 11B are diagrams illustrating the state of the movable mechanism during low rotation. [Figure 2B] 11A and 11B are diagrams illustrating a state of the movable mechanism during high speed rotation. [Diagram 3] FIG. 4 is an explanatory diagram of an acting force in a movable mechanism. [Figure 4A] 6A to 6C are diagrams illustrating the action of the second permanent magnet during low rotation. [Figure 4B] 6A to 6C are diagrams illustrating the action of the second permanent magnet during high speed rotation. [Figure 5A] FIG. 4 is a diagram showing an example of magnetic flux density at low rotation speed. [Figure 5B] FIG. 4 is a diagram showing an example of magnetic flux density during high speed rotation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0010] FIG. 1 is a diagram showing the main parts of a rotating electric machine 1. FIG. 1 shows the main parts of the rotating electric machine 1 as viewed along the axial direction. FIG. 1 shows the state of the rotating electric machine 1 at high speed. The rotating electric machine 1 includes a rotor 2, a first permanent magnet 3, a stator 4, and a movable mechanism 10. The rotating electric machine 1 is a magnet-embedded type rotating electric machine in which the first permanent magnet 3 is embedded in the rotor 2, and is an inner rotor structure rotating electric machine. The rotor 2 is a rotor core and has a ring-shaped shape. The rotor 2 is formed by, for example, laminating a large number of thin electromagnetic steel sheets. The rotor 2 is provided with a magnet insertion hole, and the first permanent magnet 3 is disposed in the magnet insertion hole. The first permanent magnet 3 is formed of a bar magnet whose cross section perpendicular to the axial direction is rectangular, and the rotor 2 includes a plurality of first permanent magnets 3 per magnetic pole. The plurality of first permanent magnets 3 corresponds to a plurality of magnets and forms magnetic poles in the rotor 2. In FIG. 1, the first magnet 31 and the second magnet 32 ​​form magnetic poles as a plurality of first permanent magnets 3, and the third magnet 33 and the fourth magnet 34 form magnetic poles as a plurality of first permanent magnets 3. The first permanent magnets 3 are arranged extending obliquely with respect to the q-axis when viewed along the axial direction. The q-axis is located at the boundary between magnetic poles adjacent to each other in the circumferential direction and extends along the radial direction. The magnetization directions of the first permanent magnets 3 are opposite to each other for magnetic poles adjacent to each other in the circumferential direction. For example, when the first magnet 31 and the second magnet 32 ​​are magnetized so that the polarity on the outer periphery side is the N-pole, the third magnet 33 and the fourth magnet 34 are magnetized so that the polarity on the outer periphery side is the S-pole. The first permanent magnets 3 can be rare earth magnets such as neodymium magnets and samarium cobalt magnets, as well as ferrite magnets and alnico magnets. The stator 4, which is a stator core, has a ring-like shape and houses the rotor 2. The stator 4 is formed by stacking many thin electromagnetic steel sheets, for example. The stator 4 has a plurality of teeth 41 protruding radially inward, and a stator coil is wound around the teeth 41.

[0011] The movable mechanism 10 includes a housing frame 11, a second permanent magnet 12, a support member 13, a weight 14, a weight spring 15, and a magnet spring 16. The movable mechanism 10 is disposed on the rotor 2. The rotor 2 is provided with an insertion hole for the movable mechanism 10, and the housing frame 11 is assembled to the rotor 2 by being pushed into the insertion hole together with the movable mechanism 10. The housing frame 11 has an inverted Y-shaped cylindrical shape with the radially outer side on the upper side when viewed along the axial direction, and forms an internal space that serves as a flux barrier (magnetic barrier). A portion of the housing frame 11 that extends along the radial direction is disposed on the q axis. This portion forms a rectangular internal space (hereinafter referred to as a rectangular space) that is long in the radial direction when viewed along the axial direction. The second permanent magnet 12 is disposed in the rectangular space. A portion of the housing frame 11 that is connected from the radially outer side to the portion that forms the rectangular space forms an outer space that is narrowed at a connection portion with the formation portion, radially outward of the connection portion. In the outer space, the magnet spring 16 is connected to the housing frame 11 from the radially inner side. The movable mechanism 10 has an outer flux barrier (magnetic barrier) B1 radially outward from the second permanent magnet 12. The outer flux barrier B1 is formed by at least the outer space of the outer space and the rectangular space. The outer flux barrier B1 is formed adjacent to the second permanent magnet 12.

[0012] The portion of the housing frame 11 that is connected from the radially inner side to the portion that forms the rectangular space forms a deformed sector-shaped internal space (referred to as the deformed sector space) that is connected to the rectangular space at the circumferential center. The support member 13, the weight 14, and the weight spring 15 are arranged in the deformed sector space. The deformed sector space is formed symmetrically with respect to the q axis when viewed along the axial direction, and the inner flux barrier B2 on the radially inner side of the movable mechanism 10 is formed in the deformed sector space. The deformed sector space is formed so as to be convex toward the radially outer side when viewed along the axial direction, and the outer peripheral side wall surface that defines the deformed sector space is composed of a flat surface rather than a curved surface. The flat surface is defined as a guide slope 111 for the weight 14. The guide slope 111 is composed of a first guide slope 111a and a second guide slope 111b that extend obliquely radially outward in a direction from both sides of the second permanent magnet 12 in the circumferential direction toward the center when viewed along the axial direction, that is, in a direction toward the second permanent magnet 12 while being perpendicular to the q axis. The first guide slope 111a is provided on one circumferential side of the q axis, and the second guide slope 111b is provided on the other circumferential side of the q axis. When viewed along the axial direction, the acute angle formed by the first guide slope 111a and the q axis, and the acute angle formed by the second guide slope 111b and the q axis are set to, for example, 60°. The housing frame 11 is made of a non-magnetic material such as resin or metal.

[0013] The second permanent magnet 12 is disposed on the q axis. The second permanent magnet 12 extends along the q axis and is provided so as to be movable along the q axis. The same magnet as the first permanent magnet 3 can be used for the second permanent magnet 12. The support member 13 is connected to the second permanent magnet 12 from the radially inner side. When viewed along the axial direction, the support member 13 has an inverted Y shape with the radially outer side on the upper side. When viewed along the axial direction, the support member 13 branches and extends along the extension direction of the first guide slope 111a and the second guide slope 111b and the radial direction. The part of the support member 13 that extends along the radial direction is disposed on the q axis and connects to the second permanent magnet 12. The parts of the support member 13 that extend along the first guide slope 111a and the second guide slope 111b are disposed symmetrically with respect to the q axis. The part of the support member 13 that extends along the first guide slope 111a has a first tip portion 13a and a first opposing surface 13c. The first opposing surface 13c faces the first guide slope 111a. The portion of the support member 13 extending along the second guide slope 111b has a second tip portion 13b and a second opposing surface 13d. The second opposing surface 13d faces the second guide slope 111b. The support member 13 is made of a non-magnetic material such as non-magnetic stainless steel.

[0014] The weight 14 is provided so as to be movable in the modified sector space. A non-magnetic material such as non-magnetic tungsten is used for the weight 14. A weight spring 15 is attached to the weight 14. The weight 14 is composed of a first weight 141 and a second weight 142 arranged on both circumferential sides of the second permanent magnet 12 when viewed along the axial direction. The weight spring 15 is composed of a first weight spring 151 and a second weight spring 152 arranged on both circumferential sides of the second permanent magnet 12 when viewed along the axial direction. The first weight 141 and the second weight 142 are configured similarly to each other, and the first weight spring 151 and the second weight spring 152 are also configured similarly to each other. For this reason, the following will mainly describe the first weight 141 and the first weight spring 151 arranged on one circumferential side of the q axis.

[0015] The first weight 141 is disposed between the first guide slope 111a and the first opposing surface 13c during high speed rotation, and abuts against the first guide slope 111a. The first weight 141 is further abutted against the first opposing surface 13c. When viewed along the axial direction, the first weight 141 has surfaces along the first opposing surface 13c, the first guide slope 111a, and the side surface of the housing frame 11 on one circumferential side that forms the deformed sector space. The first weight 141 has the following surface on the q-axis side. That is, when viewed along the axial direction, the first weight 141 has a slope that extends obliquely radially outward in a direction from one circumferential side of the second permanent magnet 12 toward the q-axis. The slope faces the second opposing slope 142a of the second weight 142 as the first opposing slope 141a. In other words, the first weight 141 and the second weight 142 have a first opposing inclined surface 141a and a second opposing inclined surface 142a, which are opposing inclined surfaces that extend obliquely radially outward in a direction from both circumferential sides of the second permanent magnet 12 toward the center when viewed along the axial direction. The first opposing inclined surface 141a and the second opposing inclined surface 142a enable the support member 13 to support the weight 14 during low rotation, which will be described later. When the first weight 141 abuts against the first guide inclined surface 111a, the acute angle formed by the first opposing inclined surface 141a and the q axis when viewed along the axial direction is set to a very small angle (for example, a few degrees). The same is true for the second opposing inclined surface 142a.

[0016] The first weight spring 151 is, for example, a coil spring, and is attached to the first weight 141. The first weight spring 151 is disposed between the first weight 141 and a side surface of the housing frame 11 on one circumferential side that forms the deformed sector space. The first weight spring 151 connects the housing frame 11 and the first weight 141 by connecting them. The first weight spring 151 exerts a spring force along the extension direction of the first guide slope 111a when viewed along the axial direction. The first weight spring 151 exerts a spring force along a direction perpendicular to the axial direction. The first weight spring 151 is provided so as to be in a stretched state during high speed rotation, that is, in a state extended from its natural length.

[0017] The magnet spring 16 is, for example, a coil spring, and is attached to the second permanent magnet 12. The magnet spring 16 is disposed radially outside the second permanent magnet 12. The magnet spring 16 is disposed on the q-axis. The magnet spring 16 connects the housing frame 11 and the second permanent magnet 12 by connecting the outer peripheral surface of the portion of the housing frame 11 that forms the outer space to the second permanent magnet 12. The magnet spring 16 exerts a spring force along the q-axis when viewed along the axial direction. The magnet spring 16 exerts a spring force along a direction perpendicular to the axial direction. The magnet spring 16 is disposed so as to be in a tensioned state during high speed rotation.

[0018] FIG. 2A is a diagram showing a state of the movable mechanism 10 at low rotation. FIG. 2B is a diagram showing a state of the movable mechanism 10 at high rotation. At low rotation, the first rotation speed is reached, and at high rotation, the rotating electric machine 1 rotates at a second rotation speed that is higher than the first rotation speed. At low rotation, the second permanent magnet 12 is located at a retracted position on the radially outer side shown in FIG. 2A. The retracted position is the original position, and at the retracted position, the second permanent magnet 12 abuts against the housing frame 11 from the radially inner side and is accommodated in the rectangular space. At the retracted position, the support member 13 abuts against the first opposing inclined surface 141a and the second opposing inclined surface 142a at the first tip portion 13a and the second tip portion 13b. When the second permanent magnet 12 is in the retracted position, the weight spring 15 does not generate a pulling force, and the first tip 13a and the second tip 13b abut against the first opposing inclined surface 141a and the second opposing inclined surface 142a due to a force acting radially outward on the second permanent magnet 12 and the support member 13. Therefore, the support member 13 supports the weight 14 by a force acting radially outward on the second permanent magnet 12 and the support member 13 during low rotation. As a result, the weight 14 is maintained in abutment against the guide inclined surface 111 even during low rotation.

[0019] As the rotation speed of the rotating electric machine 1 increases, the centrifugal force increases. As a result, the weight 14 moves radially outward along the guide slope 111 while pushing the support member 13 radially inward. This causes the second permanent magnet 12 to move radially inward together with the support member 13, that is, in a direction away from the stator 4. The second permanent magnet 12 moves in a direction away from the stator 4 at a portion facing the second permanent magnet 12 with the outer flux barrier B1 in between. The radial length of the outer flux barrier B1 changes in response to the movement of the second permanent magnet 12, and the radial length becomes longer when the second permanent magnet 12 moves radially inward. The radial length corresponds to the length in the direction connecting the second permanent magnet 12 and the stator 4.

[0020] When the weight 14 moves radially outward to a certain extent, the contact portion of the support member 13 with the weight 14 changes from the first tip portion 13a and the second tip portion 13b to the first opposing surface 13c and the second opposing surface 13d. When the support member 13 is in contact with the weight 14 at the first opposing surface 13c and the second opposing surface 13d, the support member 13 does not move even if the weight 14 moves. As a result, the second permanent magnet 12 is positioned at the forward position on the radial inside as shown in FIG. 2B. The weight 14 can move radially outward until it contacts the second permanent magnet 12. The housing frame 11 may be provided with a stopper against which the weight 14 comes in contact when the second permanent magnet 12 is positioned at the forward position, and which restricts the weight 14 from moving radially outward.

[0021] FIG. 3 is an explanatory diagram of the acting forces in the movable mechanism 10. When the rotating electric machine 1 is in operation, the second permanent magnet 12 is subjected to a centrifugal force F1 and an attractive force F2 acting radially outward. A centrifugal force F3 acts radially outward on the support member 13, and a centrifugal force F4 acts radially outward on the weight 14. The centrifugal force F4 of the weight 14 is composed of a first centrifugal force F41 acting on the first weight 141 and a second centrifugal force F42 acting on the second weight 142. The centrifugal force F1 and the attractive force F2 of the second permanent magnet 12 and the centrifugal force F3 of the support member 13 constitute a magnet side resultant force, which is a force that resists the centrifugal force F4 of the weight 14 when the second permanent magnet 12 is moved radially inward. For this reason, the mass of the weight 14 is set to a mass at which the centrifugal force F4 becomes larger than the magnet side resultant force at the time of transition from low rotation to high rotation, i.e., at high rotation. As a result, the centrifugal force F4 of the weight 14 overcomes the magnet side resultant force when transitioning from low rotation to high rotation, making it possible to position the second permanent magnet 12 in a radially inward forward position when high rotation.

[0022] Furthermore, in this embodiment, the radial component F5 of the spring force of the weight spring 15 (the radial component F51 of the spring force of the first weight spring 151 and the radial component F52 of the spring force of the second weight spring 152) and the spring force F6 of the magnet spring 16 also act as forces that resist the centrifugal force F4 of the weight 14 when moving the second permanent magnet 12 radially inward. For this reason, the mass of the weight 14 is set to a mass in which the centrifugal force F4 is added to the magnet side resultant force at high rotation speed and is greater than the magnitude of the radial component F5 and the magnitude of the spring force F6. This allows the second permanent magnet 12 to be positioned at the radially inward forward position even when the weight spring 15 and the magnet spring 16 are generating a pulling force at high rotation speed.

[0023] When the rotation speed changes from high to low, the centrifugal force F4 of the weight 14 decreases in response to the decrease in the rotation speed of the rotating electric machine 1. As a result, the weight spring 15 starts to move the weight 14 toward the retracted position radially outward against the centrifugal force F4, and the second permanent magnet 12 finally returns to the retracted position. When the rotation speed changes from high to low and when the rotation speed is low, the support member 13 supports the weight 14 by using the spring force F6 of the magnet spring 16. Therefore, when the rotation speed changes from high to low, the weight 14 moves toward the radial inside while being supported by the support member 13. The movable mechanism 10 changes the magnetic flux to the stator 4 by moving the second permanent magnet 12 in response to the rotation speed of the rotor 2, as will be described next.

[0024] FIG. 4A is a diagram for explaining the action of the second permanent magnet 12 at low rotation speed. FIG. 4B is a diagram for explaining the action of the second permanent magnet 12 at high rotation speed. In FIG. 4A and FIG. 4B, the configuration and shape of the arrangement are appropriately simplified. As shown in FIG. 4A and FIG. 4B, the second permanent magnet 12 forms a magnetic flux from the inside to the outside in the radial direction. As shown in FIG. 4A, when the second permanent magnet 12 is located at the retracted position on the outside in the radial direction, the radial length of the outer flux barrier B1 is shortened by the amount that the second permanent magnet 12 is closer to the stator 4. In other words, the air gap between the second permanent magnet 12 and the stator 4 is reduced. As a result, in this case, the magnetic resistance is reduced, and the magnetic flux to the stator 4 is increased by that amount, so that the flux linkage to the stator 4 is increased. As shown in FIG. 4B, when the second permanent magnet 12 is located at the advanced position on the inside in the radial direction, the radial length of the outer flux barrier B1 is longer by the amount that the second permanent magnet 12 is farther from the stator 4. In other words, the radial length of the outer flux barrier B1 increases as the second permanent magnet 12 moves radially inward, which increases the air gap between the second permanent magnet 12 and the stator 4. As a result, in this case, not only does the second permanent magnet 12 move away from the stator 4, but the magnetic resistance increases, so the magnetic flux to the stator 4 decreases. As a result, the flux linkage to the stator 4 decreases, and the induced voltage is suppressed. In addition, at this time, the field weakening current can be suppressed by the amount of the suppression of the induced voltage, so copper loss can be reduced and the efficiency of the rotating electric machine 1 can be improved.

[0025] FIG. 5A is a diagram showing an example of magnetic flux density in the case of this embodiment. FIG. 5B is a diagram showing an example of magnetic flux density in the case of the comparative example. In the comparative example, the movable mechanism 10 is not provided, and the second permanent magnet 12 is located at the retracted position regardless of the rotation speed of the rotating electric machine 1. FIGS. 5A and 5B show the magnetic flux density in the periphery of the retracted position of the second permanent magnet 12 at high rotation. In the case of this embodiment shown in FIG. 5A, the second permanent magnet 12 is located at the radially inner advanced position at high rotation, and is not located at the retracted position. As a result, in the case of this embodiment, it can be seen that the magnetic flux density is reduced in the region R of the stator 4 compared to the case of the comparative example shown in FIG. 5B. That is, in the case of this embodiment, the second permanent magnet 12 is not located at the retracted position at high rotation, so the radial length of the outer flux barrier B1 is longer than in the comparative example. As a result, in the case of this embodiment, the interlinkage magnetic flux to the stator 4 can be reduced compared to the comparative example at high rotation.

[0026] Next, the main effects of this embodiment will be described.

[0027] The rotating electric machine 1 has a rotor 2 and a stator 4, and a second permanent magnet 12 is arranged on the rotor 2. The rotating electric machine 1 has a movable mechanism 10 that changes the magnetic flux to the stator 4 by moving the second permanent magnet 12 according to the rotation speed of the rotor 2. According to this configuration, by moving the second permanent magnet 12 with the movable mechanism 10, for example, the magnetic flux to the stator 4 can be changed by changing the distance between the second permanent magnet 12 and the stator 4. Therefore, by moving the second permanent magnet 12 with the movable mechanism 10, it is possible to reduce the interlinkage magnetic flux to the stator 4 at high rotation speeds and suppress the induced voltage. In addition, since the field weakening current can be suppressed by the amount of the suppression of the induced voltage, copper loss can be reduced, and the efficiency of the rotating electric machine can be improved. Furthermore, since the movable mechanism 10 moves the second permanent magnet 12 arranged on the rotor 2, the range of reduction in the interlinkage magnetic flux does not concentrate on the axial end of the rotating electric machine 1, as in the case where a magnetic flux variable mechanism is provided on the axial end face of the rotor core, and the axial length of the rotating electric machine 1 does not become long. In addition, by returning the second permanent magnet 12 to the retracted position by the movable mechanism 10 during low rotation, it is possible to increase the magnetic flux linkage to the stator 4, making it possible to ensure torque during low rotation.

[0028] In this embodiment, the movable mechanism 10 is a mechanism that reduces the magnetic flux to the stator 4 by moving the second permanent magnet 12 radially inward. With this configuration, it is possible to move the second permanent magnet 12 away from the stator 4 during high rotation, so that it is possible to reduce the interlinkage magnetic flux to the stator 4 during high rotation.

[0029] In this embodiment, the movable mechanism 10 has an outer flux barrier B1 radially outward from the second permanent magnet 12. The radial length of the outer flux barrier B1 increases as the second permanent magnet 12 moves radially inward. With this configuration, the outer flux barrier B1 can reduce the magnet magnetic flux to the stator 4 during high rotation, thereby reducing the flux linkage to the stator 4 during high rotation.

[0030] In this embodiment, the movable mechanism 10 includes a weight 14 that moves due to centrifugal force F4 to move the second permanent magnet 12. With this configuration, the second permanent magnet 12 is subjected to centrifugal force acting radially outward, i.e., toward the stator 4, and it is possible to move the second permanent magnet 12 radially inward by using the weight 14 when transitioning from low rotation to high rotation. In addition, since the centrifugal force of the weight 14 is used, it is advantageous in terms of simplifying the configuration and reducing costs.

[0031] In this embodiment, the movable mechanism 10 further includes a weight spring 15 attached to the weight 14, and when the second permanent magnet 12 returns to the retracted position, the weight spring 15 contracts due to the spring force of the weight spring 15. With this configuration, the second permanent magnet 12 can be returned to the retracted position by utilizing the spring force of the weight spring 15 when transitioning from high rotation to low rotation.

[0032] In this embodiment, the movable mechanism 10 further includes a housing frame 11 that is assembled to the rotor 2 by being pushed into an insertion hole provided in the rotor 2. According to such a configuration, the housing frame 11 can be assembled to the rotor 2 by pushing the movable mechanism 10 together with the rotor 2, improving the ease of assembly of the movable mechanism 10.

[0033] In this embodiment, the weight 14 is a first weight 141 and a second weight 142, which are weights provided on both sides of the second permanent magnet 12 in the circumferential direction. The first weight 141 and the second weight 142 have a first opposing inclined surface 141a and a second opposing inclined surface 142a, which are opposing inclined surfaces extending obliquely from both sides of the circumferential direction of the second permanent magnet 12 toward the center, respectively, in the radially outward direction when viewed along the axial direction. The movable mechanism 10 further includes a support member 13 that is connected to the second permanent magnet 12 and abuts against the first opposing inclined surface 141a and the second opposing inclined surface 142a when the second permanent magnet is in the retracted position. According to this configuration, the support member 13 abutting against the first opposing inclined surface 141a and the second opposing inclined surface 142a supports the weight 14 during low rotation, and a structure capable of appropriately arranging the weight 14 is obtained.

[0034] In this embodiment, the housing frame 11 has a first guide slope 111a and a second guide slope 111b that extend obliquely from both sides in the circumferential direction of the second permanent magnet 12 toward the center when viewed along the axial direction, and guides the first weight 141 and the second weight 142. The support member 13 branches and extends along the extension direction of the first guide slope 111a and the second guide slope 111b and the radial direction when viewed along the axial direction. The support member 13 is connected to the second permanent magnet 12 at a portion that branches and extends along the radial direction. When the second permanent magnet 12 is in the retracted position, the support member 13 abuts against the first opposing slope 141a and the second opposing slope 142a at a first tip portion 13a and a second tip portion 13b that are the tip portions of the portions that branch and extend along the extension direction of the first guide slope 111a and the second guide slope 111b, respectively. The first weight 141 and the second weight 142 move radially outward along the corresponding guide slope 111 of the first guide slope 111a and the second guide slope 111b due to centrifugal force, thereby moving the support member 13 radially inward, and thereby moving the second permanent magnet 12 radially inward.

[0035] According to this configuration, when the rotation speed changes from low to high, the weight 14 is moved radially outward while being guided by the guide slope 111 in response to an increase in the centrifugal force F4, thereby obtaining a structure capable of moving the second permanent magnet 12 radially inward. Furthermore, when the rotation speed changes from high to low, the weight 14 is moved radially inward while being supported by the support member 13 in response to a decrease in the centrifugal force F4, thereby obtaining a structure capable of moving the second permanent magnet 12 radially outward. Furthermore, when the rotation speed changes from low to high, the weight 14 is supported by the support member 13, the first end portion 13a and the second end portion 13b of which abut against the first opposing slope 141a and the second opposing slope 142a, thereby obtaining a structure capable of supporting the weight 14. In other words, a structure suitable for the entire operation of the rotating electric machine 1 is obtained.

[0036] In this embodiment, the weight 14 is made of a non-magnetic material. With this configuration, even if the weight 14 is arranged on the rotor 2, it is possible to prevent the weight 14 from being affected by magnetic flux such as the magnetic flux of the second permanent magnet 12 arranged on the rotor 2.

[0037] In this embodiment, the rotor 2 includes a plurality of first permanent magnets 3 per magnetic pole. The second permanent magnet 12 is disposed on the q-axis located at the boundary between magnetic poles adjacent in the circumferential direction formed on the rotor 2 by the plurality of first permanent magnets 3, and moves along the radial direction. With this configuration, the moving second permanent magnet 12 can be appropriately disposed on the rotor 2 while the magnetic poles are formed on the rotor 2 by the plurality of first permanent magnets 3.

[0038] In this embodiment, the movable mechanism 10 further includes a magnet spring 16 disposed radially outside the second permanent magnet 12 and attached to the second permanent magnet 12, and a mechanism is adopted in which the magnet spring 16 contracts due to the spring force of the magnet spring 16 when the second permanent magnet 12 returns to its original position. With this configuration, the second permanent magnet 12 can be returned to its retracted position by utilizing the spring force of the magnet spring 16 when transitioning from high rotation to low rotation. In addition, the weight 14 can be supported by the support member 13 by utilizing the spring force of the magnet spring 16 when transitioning from high rotation to low rotation or at low rotation.

[0039] Although the embodiments of the present invention have been described above, the above-mentioned embodiments merely show some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above-mentioned embodiments.

[0040] For example, the movable mechanism 10 may not include the housing frame 11, and the outer flux barrier B1 may be formed by a hole provided in the rotor 2. The rotating electric machine 1 may also be an outer rotor structure rotating electric machine. In this case, the movable mechanism 10 may be, for example, a mechanism in which the second permanent magnet 12 arranged in the outer rotor moves radially outward, that is, in a direction away from the stator, by centrifugal force, thereby reducing the magnetic flux to the stator housed in the outer rotor. In this case, the second permanent magnet 12 may be provided with a return spring that returns the second permanent magnet 12 to its original position radially inward when transitioning from high rotation to low rotation. [Explanation of symbols]

[0041] 1 Rotating Electric Machine 2 Rotors 3 First permanent magnet 10 Movable mechanism 11 Housing frame 111 Guide slope 12 Second permanent magnet (magnet) 13 Support member 13a 1st tip 13b 2nd tip 13c First opposing surface 13d Second opposing surface 14 Weight 141a First opposing slope 142a Second opposing slope 15 Weight spring 16 Magnet spring B1 Outer flux barrier (flux barrier)

Claims

1. A rotating electric machine having a rotor and a stator, and a magnet disposed on the rotor, a movable mechanism that changes a magnetic flux of the magnet to the stator by moving the magnet in accordance with a rotation speed of the rotor, the movable mechanism is a mechanism for reducing a magnetic flux to the stator by moving the magnet in a direction away from the stator, and includes a weight that moves the magnet by centrifugal force, and a housing frame that is assembled to the rotor by being pushed into an insertion hole provided in the rotor, The weights are weights provided on both sides of the magnet in the circumferential direction, and each weight has an opposed inclined surface that extends obliquely radially outward in a direction from both sides of the magnet in the circumferential direction toward the center when viewed along the axial direction, The movable mechanism further includes a support member connected to the magnet and abutting each of the opposing slopes when the magnet is in its original position. A rotating electric machine characterized by:

2. A rotating electric machine having a rotor and a stator, and a magnet disposed on the rotor, a movable mechanism that changes a magnetic flux of the magnet to the stator by moving the magnet in accordance with a rotation speed of the rotor, the movable mechanism is a mechanism for reducing a magnetic flux to the stator by moving the magnet in a direction away from the stator, and includes a weight that moves the magnet by centrifugal force; The rotor has a plurality of magnets per magnetic pole, the magnet is disposed on a q-axis located at a boundary between magnetic poles adjacent to each other in a circumferential direction formed on the rotor by the plurality of magnets, and moves along a radial direction; A rotating electric machine characterized by:

3. 3. A rotating electric machine according to claim 1, the movable mechanism has a flux barrier between the magnet and the stator, The flux barrier has a length extending in a direction connecting the magnet and the stator as the magnet moves in a direction away from the stator. A rotating electric machine characterized by:

4. A rotating electric motor described in any one of claims 1 to 3. The movable mechanism further includes a weight spring attached to the weight, and the weight spring is compressed by the spring force of the weight spring when the magnet returns to its original position. A rotating electric machine characterized by:

5. A rotating electric machine as claimed in claim 2, The movable mechanism further includes a housing frame that is assembled to the rotor by being pushed into an insertion hole provided in the rotor. A rotating electric machine characterized by:

6. A rotating electric machine according to claim 5, The weights are weights provided on both sides of the magnet in the circumferential direction, and each weight has an opposed inclined surface that extends obliquely radially outward in a direction from both sides of the magnet in the circumferential direction toward the center when viewed along the axial direction, The movable mechanism further includes a support member connected to the magnet and abutting each of the opposing slopes when the magnet is in its original position. A rotating electric machine characterized by:

7. A rotating electric machine according to claim 1 or 6, the housing frame extends obliquely radially outward from both sides of the magnet in the circumferential direction toward the center when viewed along the axial direction, and has guide slopes that guide the weights, When viewed along the axial direction, the support member branches and extends along the extension direction of each of the guide slopes and the radial direction, and is connected to the magnet at the portion branched and extended along the radial direction, and when the magnet is in its original position, each tip of the portion branched and extended along the extension direction of each of the guide slopes abuts against each of the opposing slopes, the weight moves radially outward along the corresponding one of the guide slopes by centrifugal force, thereby moving the support member radially inward, thereby moving the magnet radially inward. A rotating electric machine characterized by:

8. A rotating electric machine according to any one of claims 1 to 7, The weight is a non-magnetic material. A rotating electric machine characterized by:

9. A rotating electric machine according to any one of claims 1 to 8, The movable mechanism further includes a magnet spring disposed radially outside the magnet and attached to the magnet, and the magnet spring is compressed by the spring force of the magnet spring when the magnet returns to its original position. A rotating electric machine characterized by:

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