Rotor

Abstract

To provide a rotor capable of moving a magnetic material to an initial position when rotation stops or a rotational frequency is lower than a predetermined value.SOLUTION: A rotor 10 includes an end plate 3. The end plate 3 includes: a first member 31 that is disposed to be adjacent to a rotor core 2, is able to move between an initial position in an axial direction when rotation stops and an operation position in an axial direction at the time of rotation at a rotational frequency equal to or higher than a predetermined value, the operation position being closer to the rotor core 2 than the initial position, and is at least partially formed of a magnetic material; a second member 32; a flow path space 30 that is formed between the first member 31 and the second member 32, through which a liquid can flow; a return-direction force application part 31d that applies a biasing force or an attraction force in a direction to return the first member 31 from the operation position to the initial position, to the first member 31; and a chamber part 34 that is a part of the flow path space 30 and placed at a radially outer part of the end plate 3, and stores the liquid.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a rotor having an end plate. [Background technology]

[0002] 2. Description of the Related Art Conventionally, rotors equipped with end plates are known (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses a rotating electric machine including a stator around which a stator coil is wound, a rotor having a rotor core with permanent magnets embedded therein and arranged with a predetermined gap on the inner circumferential side of the stator, and a magnetic flux variable mechanism that changes the magnetic flux from the permanent magnets of the rotor core to the stator coil according to the rotation speed of the rotor. In Patent Document 1, when the induced voltage increases due to an increase in the rotation speed of the rotor, the magnetic flux variable mechanism short-circuits the magnetic flux (allowing part of the magnetic flux to escape in a direction different from the stator side) to prevent the induced voltage from exceeding the drive voltage of the rotating electric machine.

[0004] In the above-mentioned Patent Document 1, the magnetic flux variable mechanism includes a case body fixed to one end surface of the rotor core, a mover whose axial movement is restricted by the case body and has an inclined surface inclined with respect to the axial direction, a cam member that contacts the inclined surface of the mover and has a cam surface inclined with respect to the axial direction, a magnetic flux short-circuiting member integrally provided with the cam member, and a biasing spring that biases the cam member toward the opposite side of the rotor in the axial direction. In Patent Document 1, the inclined surface of the mover slides in the axial direction along the cam surface of the cam member due to centrifugal force according to the rotation speed of the rotor. When the rotation speed of the rotor increases, the position where the mover and the cam member contact each other changes, and the part of the mover with a large axial length comes into contact with the part of the cam member with a large axial length, and the cam member is pressed toward the rotor, so that the cam member moves toward the rotor against the biasing force of the biasing spring. Furthermore, when the cam member is pressed toward the rotor, the magnetic flux short-circuiting member moves toward the rotor together with the cam member, so that the magnet and the magnetic flux short-circuiting member approach each other, and a magnetic flux short-circuit occurs. In addition, when the rotation speed of the rotor decreases, the cam member is urged by the urging member to move toward the case body away from the rotor, and the inclined surface of the moving body slides along the cam member, thereby returning the magnetic flux short-circuiting member to the position it was in when the rotor stopped rotating. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6965705 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the rotor described in the above Patent Document 1, in order to move the cam member and the magnetic flux short-circuiting member in the axial direction, it is necessary to slide the cam surface of the cam member and the inclined surface of the moving element. When the cam member and the moving element are continuously slid, due to changes over time, a difference occurs between the inclination angle of the inclined surface of the moving element and the inclination angle of the cam surface of the cam member, or a difference occurs between the surface roughness of the inclined surface and the surface roughness of the cam surface, making it difficult for the moving element to slide smoothly along the cam member. As a result, the force required to move the moving element becomes large, and it may become difficult to move the magnetic flux short-circuiting member (magnetic body) from a position during rotation to an initial position when rotation is stopped or when the number of rotations is less than a predetermined number, using only the biasing force of the biasing member.

[0007] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a rotor that can easily move a magnetic body to an initial position when rotation is stopped or when the rotation speed is less than a predetermined number of rotations. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, a rotor in one aspect of the present invention comprises a rotor shaft rotatable about an axis, a rotor core including a permanent magnet fixed to the rotor shaft and extending in the axial direction, and an end plate arranged on the end face side of the rotor core in the axial direction, the end plate being arranged close to the rotor core and movable between an initial position in the axial direction when rotation is stopped and an operating position in the axial direction when rotation is at or above a predetermined rotation speed that is closer to the rotor core than the initial position, the end plate including a first member at least a portion of which is made of a magnetic material, a second member arranged farther from the rotor core than the first member, a flow path space formed between the first member and the second member through which liquid can flow, a return direction force imparting portion that imparts a biasing force or suction force to the first member in a direction returning the first member from the operating position to the initial position, and a chamber portion for storing liquid that is part of the flow path space and is provided on the radially outer portion of the end plate.

[0009] In the rotor according to one aspect of the present invention, as described above, the end plate is arranged close to the rotor core and is movable between an initial position in the axial direction when the rotor core stops rotating and an operating position in the axial direction when the rotor core rotates at a predetermined rotation speed or more, and includes a first member at least partly made of a magnetic material, a second member arranged farther away from the rotor core than the first member, a flow path space formed between the first member and the second member through which liquid can flow, a return direction force applying portion that applies a biasing force or a suction force to the first member in a direction returning the first member from the operating position to the initial position, and a chamber portion that is a part of the flow path space and is provided on the radial outer side of the end plate and that stores liquid. As a result, a centrifugal force directed radially outward is applied to the liquid in the chamber portion due to the rotation of the rotor. In addition, the liquid located at the outer circumferential end of the chamber portion cannot flow radially outward from the chamber portion, so that the radial centrifugal force applied to the liquid is dispersed into an axial force. As a result, when the centrifugal force increases as the rotation speed of the rotor becomes equal to or greater than a predetermined rotation speed, and the axial force toward the rotor core due to the centrifugal force becomes greater than the biasing force or attractive force of the return direction force application unit, the liquid in the chamber unit pushes the first member toward the rotor core, so that the first member moves toward the rotor core and the magnetic body can be brought closer to the permanent magnet of the rotor core. Also, when the centrifugal force decreases as the rotation speed of the rotor core becomes less than a predetermined rotation speed, and the axial force toward the rotor core due to the centrifugal force becomes smaller than the biasing force or attractive force of the return direction force application unit, the return direction force application unit biases the first member toward the second member, so that the first member moves to the initial position and the magnetic body can be separated from the permanent magnet of the rotor core. Also, unlike a case in which a moving element and a cam member are provided and the magnetic body is moved by linking the movement of the moving element and the movement of the cam member, the magnetic body is moved by simply moving the first member in the axial direction by the force toward the rotor core due to the centrifugal force or the biasing force or attractive force of the return direction force application unit, which is composed of the first member and the second member.Therefore, since there is no need to provide the first member with an inclined surface that slides against the other member, there is no difference in the inclination angle of the inclined surface of the first member and the inclination angle of the surface of the other member due to changes over time, and no difference in the surface roughness of the inclined surface of the first member and the surface roughness of the other member, and it is possible to suppress the generation of a force that resists the biasing force or attractive force of the return direction force imparting part. As a result, it is possible to easily move the first member by the biasing force or attractive force of the return direction force imparting part, so that when rotation is stopped or the number of rotations is less than a predetermined number, the magnetic body can be easily moved to the initial position.

[0010] In the rotor according to the above aspect, the magnetic body is preferably provided on the rotor core side surface of the first member so as to be able to come into contact with the permanent magnet when moved to the operating position, and the return force imparting portion is arranged at a spaced position not in contact with the permanent magnet in a direction perpendicular to the axial direction.

[0011] With this configuration, when the first member moves to the operating position, the magnetic body can be brought into contact with the permanent magnet, so that a short circuit of the magnetic flux can be reliably generated. Furthermore, since the return direction force application part is disposed at a position separated from the permanent magnet so as not to contact the permanent magnet, the return direction force application part can be prevented from coming into contact with the permanent magnet. As a result, when the return direction force application part is disposed in contact with the rotor core and is constituted by a metal spring member or magnet, it is possible to prevent the return direction force application part from coming into contact with the permanent magnet of the rotor core and causing a short circuit of the magnetic flux by the return direction force application part.

[0012] In the rotor according to the above aspect, the return direction force imparting portion preferably includes a spring member that elastically deforms so that the first member approaches the operating position as the rotation speed of the rotor core increases, and returns to its original elastically deformed state so that the first member approaches the initial position as the rotation speed of the rotor core decreases.

[0013] With this configuration, the first member can be moved between the initial position and the operating position using the spring member, thereby simplifying the structure compared to the conventional case in which a cam member and a moving element having an inclined surface are provided.

[0014] In the rotor according to the above aspect, the first member is preferably configured to move to the operating position when a force pressing the first member toward the rotor core, generated by centrifugal force when the rotor core rotates, is greater than the return direction force of the return direction force imparting portion.

[0015] With this configuration, when the rotation speed of the rotor exceeds a predetermined value and the force pressing the first member toward the rotor core due to the centrifugal force generated when the rotor rotates exceeds a predetermined magnitude, the first member moves to the operating position, thereby causing the magnetic body to short-circuit the magnetic flux of the permanent magnet. Also, when the rotation speed of the rotor is equal to or lower than the predetermined rotation speed and the force pressing the first member toward the rotor core due to the centrifugal force generated when the rotor rotates falls to or lower than the predetermined magnitude, the first member moves to the initial position, thereby preventing the magnetic flux of the permanent magnet from being short-circuited by the magnetic body.

[0016] In the rotor according to the above aspect, the following configuration is also possible.

[0017] (Additional note 1) In the rotor according to the aforementioned aspect, the first member preferably includes a placement recess provided on a surface facing the rotor core and for accommodating the return direction force application portion.

[0018] With this configuration, the return force application portion is housed within the first member by providing the placement recess, so that the axial size of the first member can be reduced, unlike when the return force application portion is provided on the rotor core side surface of the first member. As a result, the axial size of the entire end plate can be prevented from increasing.

[0019] (Additional note 2) In the above-mentioned configuration in which the return direction force application portion includes a spring member, the spring member preferably includes a leaf spring.

[0020] By configuring it in this manner, the leaf spring has a smaller size (length) in the direction of elastic deformation compared to a coil spring, so that when the leaf spring is installed in the first member with the direction of elastic deformation aligned with the axial direction, the axial size (length) of the first member can be prevented from becoming larger.

[0021] (Additional note 3) In this case, preferably, a plurality of leaf springs are arranged at predetermined angular intervals in the circumferential direction.

[0022] With this configuration, the leaf springs are arranged at predetermined angular intervals in the circumferential direction, so that the biasing force of the leaf springs can be applied to the entire first member, allowing the first member to be moved stably. Also, by arranging a plurality of leaf springs, the biasing force that moves the first member from the actuated position to the initial position can be increased, allowing the first member to be returned from the actuated position to the initial position more easily.

[0023] (Additional note 4) In the above rotor, the first member is preferably formed entirely from a magnetic material, or a portion of its surface facing the rotor core is formed from a magnetic material.

[0024] With this configuration, when the entire first member is made of a magnetic material, the permanent magnet and the magnetic material can be reliably brought into contact with each other, and therefore a short circuit of the magnetic flux can be reliably generated. Also, when a part of the first member is made of a magnetic material, the parts other than the magnetic material can be made of a material that is lighter than the magnetic material, and therefore the weight of the first member can be reduced. As a result, unlike when the weight of the first member is heavy, the first member can be easily returned to the initial position by the biasing force or attractive force in the return direction by the return direction force application part.

[0025] (Additional note 5) In the above rotor, the first member and the second member are preferably configured to be able to move relative to each other in the axial direction while maintaining contact, and the liquid flowing radially outward collides with the radial inner end surface of the chamber portion, causing the liquid in the chamber portion to press the first member toward the rotor core against the force of the return force imparting portion.

[0026] With this configuration, the first member and the second member are configured to be able to move relative to each other in the axial direction while maintaining contact, so that the first member can be moved without leaking the liquid in the chamber to the outside. In addition, the liquid flowing radially outward collides with the radially inner end surface of the chamber, so that the liquid in the chamber presses the first member toward the rotor core against the force of the return direction force application part, so that there is no need to provide a separate drive source for moving the first member to the operating position. As a result, the rotor structure can be prevented from becoming complicated.

[0027] (Additional note 6) In the above rotor, the first member is preferably annular.

[0028] With this configuration, the chamber can be made annular, so that supplying liquid to a portion of the chamber causes the liquid to flow along the outer periphery, thereby supplying the liquid to the entire chamber. Also, because the centrifugal force caused by the rotation of the rotor can be applied evenly to the liquid in the chamber, the force generated by the centrifugal force pressing the first member toward the rotor core can be applied evenly to the first member.

[0029] (Additional note 7) In the rotor described above, a seal member is preferably provided at a portion where the first member and the second member contact each other.

[0030] With this configuration, it is possible to further prevent the liquid in the chamber from leaking to the outside. [Brief description of the drawings]

[0031] [Figure 1] 1 is a cross-sectional view showing a rotating electric machine including a rotor according to an embodiment, taken from an axial direction; [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. 2 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 2 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] 1A and 1B are views showing a first member, in which (A) is a view of the first member seen from the Z1 side, and (B) is a view of the first member seen from the Z2 side. [Figure 6] FIG. 13 is a view of the second member as seen from the Z2 side. [Figure 7] 1A and 1B are diagrams showing methods of forming rotor core flow passages, in which (A) shows an example in which the flow passages are provided at a position away from the magnets, and (B) shows an example in which the flow passages are provided adjacent to the magnets. [Figure 8] 5A and 5B are diagrams for explaining forces acting on a rotor in the present embodiment. [Figure 9] 6A and 6B are diagrams illustrating the magnetic flux of a permanent magnet when a first member is located at an initial position. [Figure 10] FIG. 4 is a diagram showing the magnetic flux of a permanent magnet when the first member is in an actuated position. [Figure 11] FIG. 11 is a diagram showing a rotor in a first modified example. [Figure 12] FIG. 13 is a diagram showing a rotor in a second modified example. [Figure 13] FIG. 13 is a diagram showing a rotor in a third modified example. [Figure 14] FIG. 13 is a diagram showing a rotor in a fourth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0033] 1 to 10, a rotor 10 according to the present embodiment that is provided in a rotating electric machine 100 will be described. As an example, the rotating electric machine 100 is used as a motor for an automobile.

[0034] As shown in FIG. 1, the rotating electric machine 100 includes a rotor 10 and a stator 20. The rotor 10 and the stator 20 face each other in the radial direction. Specifically, the rotor 10 is disposed on the radial inside (R2 side) of the stator 20. That is, the rotating electric machine 100 of this embodiment is configured as an inner rotor type rotating electric machine. In this application, the axial direction in which the rotation center axis C extends is defined as the Z direction. The radial direction of the rotor 10 and the stator 20 is defined as the R direction, the radial outer side is defined as the R1 side, and the radial inner side is defined as the R2 side. Furthermore, the circumferential direction of the rotor 10 and the stator 20 is defined as the r direction.

[0035] The rotating electric machine 100 is configured as an interior permanent magnet motor (IPM motor). A plurality of permanent magnets form a plurality of magnetic poles arranged circumferentially.

[0036] (Rotor configuration) 2, the rotor 10 includes a rotor shaft 1, a rotor core 2, an end plate 3, a seal member 4, a fixing member 5, and a liquid discharge plate 6. In the rotor 10, the end plate 3, the rotor core 2, the liquid discharge plate 6, and the fixing member 5 are arranged in this order along the axial direction and attached to the rotor shaft 1.

[0037] (Rotor shaft configuration) As shown in FIG. 2, the rotor shaft 1 is an axial portion that serves as the center of rotation of the rotating electric machine 100. The rotor shaft 1 is formed in a cylindrical (annular) shape when viewed from the axial direction. As an example, the rotor shaft 1 is formed from steel. The rotor shaft 1 extends in the axial direction (Z direction) along a central rotation axis C. The rotor shaft 1 is rotatable around the axis (central rotation axis).

[0038] The rotor shaft 1 includes a main body portion 11, a hollow portion 12, a connecting flow passage 13, and a flange portion 14. The rotor shaft 1 includes the main body portion 11, the hollow portion 12, the connecting flow passage 13, and the flange portion 14, which are integrally configured.

[0039] The main body 11 is a cylindrical portion extending in the axial direction. The rotor core 2, the end plates 3, and the liquid discharge plate 6 are attached so as to be in contact with the outer circumferential surface of the main body 11. The axial length of the main body 11 is greater than the sum of the axial length of the end plates 3 and the axial length of the rotor core 2.

[0040] The hollow portion 12 is a hole provided on the inner periphery side of the main body portion 11. The hollow portion 12 extends in the axial direction along the central axis of rotation C. The hollow portion 12 is configured to receive liquid from a liquid supply source (not shown) in which the liquid is stored. The hollow portion 12 supplies the supplied liquid to the end plate 3. The liquid is, for example, oil. The diameter of the hollow portion 12 is smaller than the diameter of the main body portion 11. As an example, the diameter of the hollow portion 12 is larger than half the diameter of the main body portion 11. Furthermore, the main body portion 11 and the hollow portion 12 are concentric circles.

[0041] The connection flow passage 13 is a through hole for allowing the refrigerant to flow out from the hollow portion 12 to the outside of the rotor shaft 1. The connection flow passage 13 is configured by a through hole extending linearly in the radial direction (R direction). Note that, as an example, FIG. 2 shows a connection flow passage extending horizontally, but it may be inclined with respect to the radial direction. A plurality of connection flow passages 13 are provided in the circumferential direction (r direction) of the main body portion 11. As an example, eight connection flow passages 13 are provided at equal angular intervals in the circumferential direction (r direction). As an example, the connection flow passage 13 has a circular shape when viewed from the radial direction. The axial length of the connection flow passage 13 is smaller than the axial length of the flow passage space 30. Liquid flows into and passes through the connection flow passage 13 due to centrifugal force.

[0042] The flange portion 14 is provided on one end side of the main body portion 11 in the axial direction. As an example, in this embodiment, the flange portion 14 is provided on the Z1 side. The flange portion 14 has an annular shape with a radial length greater than that of the main body portion 11. The flange portion 14 is a portion that protrudes in the radial direction from the main body portion 11. The flange portion 14 is configured to press the rotor core 2, the end plate 3, and the liquid discharge plate 6 in the axial direction. Specifically, the flange portion 14 and the fixing member 5 sandwich the rotor core 2, the end plate 3, and the liquid discharge plate 6 in the axial direction, thereby fixing the rotor core 2, the end plate 3, and the liquid discharge plate 6 so that they do not move in the axial direction. The flange portion 14 is arranged on the inner peripheral side (R1 side) in the radial direction, and is not arranged on the outer peripheral side (R2 side). In other words, the radial length of the flange portion 14 is smaller than the radial length of the rotor core 2 and the radial length of the end plate 3. In detail, the radial length of the flange portion 14 is smaller than half the radial length of the rotor core 2 and the radial length of the end plate 3. The flange portion 14 is formed integrally with the main body portion 11.

[0043] (Rotor core configuration) Rotor core 2 is made of multiple electromagnetic steel plates stacked in the axial direction and configured to allow magnetic flux to pass through. Rotor core 2 has an annular shape. Rotor core 2 also includes a shaft insertion hole 21, a rotor core flow path 22, and magnet holes 23 (see FIG. 7).

[0044] The shaft insertion hole 21 is a hole for inserting the rotor shaft 1 in the axial direction. The shaft insertion hole 21 is a through hole extending in the axial direction. The shaft insertion hole 21 is formed by laminating annular electromagnetic steel plates that form the rotor core 2 in the axial direction.

[0045] The rotor core flow passage 22 extends in the axial direction in which the liquid flows. The rotor core flow passage 22 is disposed radially on the outer circumferential side (R1 side) of the shaft insertion hole 21. The rotor core flow passage 22 is a flow passage through which liquid flows for cooling the rotor core 2. This allows the liquid to cool the permanent magnets 15 that generate heat when the rotating electric machine 100 is driven.

[0046] As shown in FIG. 7, the rotor core 2 is provided with a plurality of magnet holes 23 in which the permanent magnets 15 are arranged. The permanent magnets 15 are fixed to the rotor shaft 1 and extend in the axial direction. The magnet holes 23 are arranged at a predetermined angular interval in the circumferential direction of the rotor core 2. The predetermined angular interval means an equal angular interval. As an example, the magnet holes 23 are arranged on the radially inner side close to the central axis C of rotation. The magnet holes 23 penetrate the rotor core 2 in the axial direction. In addition, resin molding is performed with the permanent magnets 15 arranged in the magnet holes 23, whereby the magnet holes 23 are sealed so that the permanent magnets 15 do not fall out. When resin molding is performed, for example, a nesting mold or a pin is inserted, and when the resin hardens, the nesting mold is removed or the pin is pulled out, thereby forming the rotor core flow passage 22.

[0047] As shown in Fig. 7(A), when the rotor core passage 22 is provided away from the permanent magnets 15, heat of the permanent magnets 15 is transferred to the liquid flowing in the rotor core passage 22 via the resin, and the permanent magnets 15 are cooled. Also, as shown in Fig. 7(B), when the rotor core passage 22 and the permanent magnets 15 are provided adjacent to each other, heat of the permanent magnets 15 is transferred to the liquid flowing in the rotor core passage 22, and the permanent magnets 15 are cooled. In this way, by efficiently cooling the permanent magnets 15, deterioration in the performance of the permanent magnets 15 can be suppressed.

[0048] As shown in FIG. 2 and FIG. 3, the end plate 3 includes a first member 31 and a second member 32. The end plate 3 includes a flow path space 30 extending in the radial direction formed by the first member 31 and the second member 32. The end plate 3 includes a chamber portion 34 that is a part of the flow path space 30 and is provided on the radial outer side of the end plate 3 and stores liquid. The radial outer end portion 30a and the inner end surface 32e of the chamber portion 34 are at the same position. The end plate 3 abuts against the flange portion 14 of the rotor shaft 1 in the axial direction. The end plate 3 is provided with a hole portion 35 for inserting the rotor shaft 1 so as to extend in the axial direction, and the inner peripheral portion of the hole portion 35 abuts against the outer peripheral portion of the rotor shaft 1. The diameter of the hole portion 35 may be the same as the diameter of the shaft insertion hole 21 of the rotor core 2, but is not necessarily the same in consideration of the balance between processing accuracy and cost. The outer diameter of the end plate 3 is the same as the outer diameter of the rotor core 2. In other words, the outer peripheral surface and the inner peripheral surface of the end plates 3 and the rotor shaft 1 are located at approximately the same position in the axial direction. As another example, when reducing the inertia of the rotor, the outer diameter of the end plates 3 may be smaller than (may be smaller than) the outer diameter of the rotor core 2. As one example, the end plates 3 are made of a non-magnetic material, and further as one example, are made of aluminum.

[0049] As shown in FIG. 2, the first member 31 has a flat plate shape extending in the radial direction. The first member 31 is disposed on the rotor core 2 side in the axial direction, and is in partial contact with the end face 24 of the rotor core 2. Specifically, the first member 31 is in contact with the axial end face 24 of the rotor core 2. A recess 31a for attaching the seal member 4 is provided on the outer circumferential surface of the first member 31 that abuts against the second member 32 in the radial direction of the first member 31. The first member 31 is disposed close to the rotor core 2. The first member 31 is movable between an initial position in the axial direction when rotation is stopped and an operating position in the axial direction when rotation is at or above a predetermined rotation speed, which is closer to the rotor core than the initial position.

[0050] As shown in FIG. 4, the first member 31 is at least partially made of a magnetic body 31c. Incidentally, the magnetic body 31c may mean that the first member 31 and the magnetic body 31c are integrally and inseparably configured, or that the magnetic body 31c is attached to the first member 31. In this embodiment, the magnetic body 31c is attached to a part of the first member 31. The magnetic body 31c is made of, for example, stainless steel. In this embodiment, the magnetic body 31c is disposed on a part of a surface 31f of the first member 31 on the rotor core 2 side, the surface 31f being made of a non-magnetic material (including a paramagnetic material, a diamagnetic material, an antiferromagnetic material, and the like, examples of which include aluminum, copper, and resins). In the drawings, as an example, the magnetic body 31c is configured so as not to protrude beyond the surface 31f of the first member 31 on the rotor core 2 side. That is, the magnetic body 31c and the surface 31f of the first member 31 on the rotor core 2 side are flush with each other (on the same plane). As another example, the magnetic body 31c may be configured to protrude beyond the surface 31f of the first member 31 on the rotor core 2 side.

[0051] The magnetic body 31c is provided on the rotor core side surface 31f of the first member 31 facing the permanent magnet 15 in the axial direction so as to be able to come into contact with the permanent magnet 15 in the operating position. As an example, the magnetic body 31c comes into contact with the permanent magnet 15 in the operating position. As another example, the magnetic body does not come into contact with the permanent magnet in the operating position (there is a small gap between the magnetic body and the permanent magnet). When viewed from the axial direction, the area of ​​the magnetic body 31c is preferably equal to or larger than the area of ​​the permanent magnet 15, but may be smaller than the area of ​​the permanent magnet 15 as long as the magnetic body 31c and the permanent magnet 15 are arranged to overlap in the axial direction. The magnetic body 31c short-circuits the magnetic flux of the permanent magnet 15. Here, short-circuiting means that a part of the magnetic flux from the permanent magnet 15 toward the stator 20 is allowed to escape in a direction different from the stator 20 side by the magnetic body 31c.

[0052] 5, the magnetic bodies 31c are arranged at predetermined angular intervals in the circumferential direction. The magnetic bodies 31c are arranged in accordance with the positions of the permanent magnets 15. The magnetic bodies 31c are arranged between the external communication hole portions 33 in the circumferential direction.

[0053] 4, a mounting recess 31e for mounting the return direction force application portion 31d is provided in the first member 31. The mounting recess 31e is provided in a surface 31f of the first member 31 on the rotor core 2 side.

[0054] As shown in Fig. 5(A), a plurality of return direction force application parts 31d are arranged circumferentially. The return direction force application parts 31d are arranged on the outer circumferential side of the magnetic body 31c. The return direction force application parts 31d are arranged at positions spaced apart from the permanent magnet 15 in a direction perpendicular to the axial direction so as not to come into contact with the permanent magnet 15. The return direction force application parts 31d apply a biasing force or a suction force to the first member 31 in a direction returning the first member 31 from the operating position to the initial position. In this embodiment, the return direction force application parts 31d are spring members that apply a biasing force to the first member 31, and more specifically, are leaf springs.

[0055] The return direction force imparting portion 31d elastically deforms so that the first member 31 approaches the operating position as the rotation speed of the rotor core 2 increases. Specifically, the leaf spring is pressed and becomes substantially flat, causing the first member 31 to approach the rotor core 2. In the return direction force imparting portion 31d, the elastic deformation state returns to its original state so that the first member 31 approaches the initial position as the rotation speed of the rotor core 2 decreases. Specifically, the leaf spring returns to its original shape, causing the first member 31 to return to the initial position. A plurality of return direction force imparting portions 31d are arranged at predetermined angular intervals in the circumferential direction.

[0056] When the rotating electric machine is driven, the rotor rotates. The rotation of the rotor generates an induced voltage. In this case, the induced voltage increases in proportion to the rotation speed of the rotor. As a result, in the past, when a certain rotation speed was reached, the induced voltage exceeded the drive voltage of the rotating electric machine, making it difficult to control the rotating electric machine.

[0057] Therefore, in the rotating electric machine 100 of this embodiment, a predetermined rotation speed is obtained from the rotation speed of the rotor 10 at which the generated induced voltage is equal to or greater than the drive voltage of the rotating electric machine 100, and a setting is made so that a short circuit of the magnetic flux occurs when the predetermined rotation speed is exceeded. Specifically, a force pressing the first member 31 against the rotor core 2 generated by the centrifugal force at the predetermined rotation speed is calculated, and a return direction force applying part 31d having an urging force or attractive force smaller than the force pressing the first member 31 against the rotor core 2 is attached to the first member 31.

[0058] As a result, when the predetermined rotation speed is reached, the first member 31 is pressed toward the rotor core 2, causing a short circuit. The predetermined rotation speed may be the same as the rotation speed of the rotor 10 at which the generated induced voltage becomes equal to or exceeds the drive voltage of the rotating electric machine 100, or may be set to be smaller than the rotation speed of the rotor 10 at which the generated induced voltage becomes equal to or exceeds the drive voltage of the rotating electric machine 100. By setting the predetermined rotation speed to be smaller, the generated induced voltage can be reliably prevented from becoming equal to or exceeds the drive voltage of the rotating electric machine 100.

[0059] As shown in FIG. 2, the first member 31 is in contact with the rotor core 2 in a portion where the return direction force application portion 31d is not provided. On the other hand, as shown in FIG. 9, the first member 31 is not in contact with the rotor core 2 when the rotation is stopped or when the rotation speed is less than a predetermined number of revolutions in a portion where the return direction force application portion 31d is provided. The first member 31 is configured to be movable in the axial direction between an initial position when the rotation is stopped and an operating position closer to the rotor core 2 than the initial position when the rotation speed is equal to or greater than the predetermined number of revolutions. FIG. 10 illustrates an example in which the first member 31 is in contact with the rotor core 2 in the operating position as an example. As another example, the first member may not be in contact with the rotor core in the operating position. The first member 31 is configured to be movable in the axial direction while maintaining a state of contact with the second member 32 and the rotor shaft 1.

[0060] As shown in Fig. 5, the first member 31 has a disk shape when viewed in the axial direction. The first member 31 is provided with a plurality of external communication holes 33. As shown in Fig. 5(A) and Fig. 5(B), the external communication holes 33 are located radially outward on the Z2 side compared to the Z1 side. As a result, the external communication holes 33 are configured to incline radially outward toward the rotor core 2 (from the Z1 side to the Z2 side).

[0061] 2, the second member 32 is provided to face the first member 31 in the axial direction. The second member 32 is provided on the opposite side to the rotor core 2 in the axial direction. The second member 32 abuts against the flange portion 14 in the axial direction. The first member 31 and the second member 32 are assembled together to form a hole portion 35 and a flow path space 30.

[0062] The second member 32 includes an inner peripheral end surface portion 32a that contacts the outer peripheral end surface 31b of the first member 31 in the radial direction, and an axial end surface portion 32b that is integrally formed with the inner peripheral end surface portion 32a and faces the first member 31 in the axial direction. The second member 32 has an L-shape.

[0063] The inner peripheral end surface portion 32a extends in the axial direction. The inner peripheral end surface portion 32a forms an inner end surface 32e of the chamber portion 34. The inner peripheral end surface portion 32a has an axial tip which contacts the outer peripheral end surface 31b of the first member 31 in the radial direction.

[0064] The axial end surface portion 32b extends in the radial direction. In this embodiment, the radial length of the axial end surface portion 32b is approximately the same as the radial length of the first member 31.

[0065] As shown in Fig. 5, the second member 32 has a disk shape when viewed in the axial direction. A diameter d3 (inner diameter of the second member 32) of the axial end face portion 32b is slightly larger than an outer diameter d1 (see Fig. 4) of the first member 31. This allows the first member 31 to be attached to the inner peripheral portion of the second member 32. In addition, the outer diameter d2 of the second member 32 is approximately the same as the outer diameter of the rotor core 2. This allows the outer diameter of the rotor core 2 and the outer diameter of the end plate 3 to be approximately the same.

[0066] The second member 32 further includes a plurality of flow passage forming portions 32c that connect to the connection flow passage 13 of the rotor shaft 1, and a plurality of attachment portions 32d for attaching the second member 32 to the first member 31. The flow passage forming portions 32c connect an annular chamber portion 34 provided on the radially outer side to the connection flow passage 13 of the rotor shaft 1. The attachment portions 32d and the flow passage forming portions 32c are arranged alternately in the circumferential direction.

[0067] The flow passage forming portions 32c extend in the radial direction and are arranged in a plurality of numbers in the circumferential direction at predetermined angular intervals. In Fig. 6, as an example, eight flow passage forming portions 32c are arranged in the circumferential direction, but this is not limiting. The flow passage forming portions 32c are portions of the axial end surface portion 32b where the attachment portions 32d are not provided, and are also gaps between the attachment portions 32d.

[0068] The mounting portion 32d has a sector shape with a circumferential length greater on the outer circumferential side than on the inner circumferential side when viewed from the axial direction. A plurality of mounting portions 32d are arranged in the circumferential direction at predetermined angular intervals. FIG. 5 shows an example in which eight flow passage forming portions 32c are arranged in the circumferential direction, but is not limited to this. The mounting portion 32d abuts against the Z1 side surface of the first member 31. The mounting portion 32d is a portion of the axial end face portion 32b that protrudes toward the rotor core 2. The axial length (protrusion amount) of the mounting portion 32d is a value obtained by subtracting the axial length of the first member 31 from the axial length of the inner circumferential end face portion 32a.

[0069] As shown in Fig. 2, at the position where the external communication hole portion 33 and the flow path forming portion 32c are provided, the liquid is directly supplied from the rotor shaft 1. On the other hand, at the position where the external communication hole portion 33 and the flow path forming portion 32c are not provided, the liquid is not directly supplied from the rotor shaft 1, as shown in Fig. 3 and Fig. 4. In this case, since the chamber portion 34 is annular, the liquid supplied by the flow path forming portion 32c provided in other portions flows along the circumferential direction, and thus the liquid is indirectly supplied.

[0070] The first member 31 and the second member 32 are configured to be able to move relative to each other in the axial direction while maintaining a contact state. Specifically, the first member 31 and the second member 32 are configured to be able to move relative to each other in the axial direction while maintaining a state in which the inner peripheral surface of the inner peripheral end surface portion 32a of the second member 32 that constitutes the inner end surface 32e of the chamber portion 34 is in contact with the outer peripheral end surface 31b of the first member 31.

[0071] The external communication hole portion 33 at least either discharges liquid from the inside of the end plate 3 to the outside or supplies liquid from the outside of the end plate 3 to the inside. In this embodiment, the external communication hole portion 33 is provided in the first member 31, and the end portion of the external communication hole portion 33 on the rotor core 2 side is connected to the rotor core flow path 22. The radial length of the external communication hole portion 33 and the radial length of the rotor core flow path 22 are approximately the same. The external communication hole portion 33 discharges liquid from the end plate 3 to the rotor core flow path 22, which is the outside.

[0072] (Configuration of sealing member) 2, the seal member 4 seals the contact portion where the first member 31 and the second member 32 contact each other. Specifically, the seal member 4 is configured to seal the contact portion between the inner peripheral end face portion 32a of the second member 32 and the outer peripheral end face 31b of the first member 31. One example of the seal member 4 is an O-ring. The seal member 4 is attached to a recess 31a provided on the outer peripheral end face 31b of the first member 31 in the radial direction.

[0073] (Configuration of fixing parts) As shown in FIG. 2, the fixing member 5 is a member for fixing the rotor core 2, the end plate 3, and the liquid discharge plate 6 in the axial direction while they are in contact with each other, and is attached to the rotor shaft 1. One example of the fixing member 5 is a nut. The fixing member 5 is disposed on the radially inner side (R2 side). One example is shown in which the diameter of the fixing member 5 is smaller than the diameter of the end plate 3, but it may be the same as the diameter of the end plate 3.

[0074] (Configuration of liquid discharge plate) 2, the liquid discharge plate 6 is disposed so as to sandwich the rotor core 2 together with the end plates 3. The liquid discharge plate 6 has a flow path 61 for discharging liquid and an insertion hole 62 into which the rotor shaft 1 is inserted. The liquid discharge plate 6 is made of, for example, a non-magnetic material. The inner and outer diameters of the liquid discharge plate 6 are approximately the same as those of the end plates 3 and the rotor core 2.

[0075] The flow path 61 is a flow path for discharging the refrigerant that has passed through the rotor core flow path 22 of the rotor core 2 to the outside of the rotor 10. As one example, the liquid discharged from the flow path 61 is configured to circulate and be supplied again to the rotor shaft 1. The flow path 61 is configured of a cylindrical through hole extending in the axial direction.

[0076] (Stator configuration) As shown in FIG. 2, the stator 20 includes a stator core 20a and a coil 20b arranged in the stator core 20a.

[0077] At both axial ends of the stator core 20a, coil end portions of the coils 20b are provided, which protrude from the stator core 20a in the axial direction. The stator core 20a is formed by laminating a plurality of electromagnetic steel plates in the axial direction, and is configured to allow magnetic flux to pass through. The coils 20b are connected to an external power supply unit, and configured to receive power (e.g., three-phase AC power). The coils 20b are configured to generate a magnetic field when power is supplied to them.

[0078] (Liquid flow) In Fig. 2, the flow of liquid is indicated by arrows. First, liquid is supplied to the hollow portion 12 of the rotor shaft 1. The liquid supplied to the rotor shaft 1 passes through the connecting flow passage 13 of the rotor shaft 1 and is supplied into the flow passage space 30 formed between the first member 31 and the second member 32. The liquid supplied to the flow passage space 30 flows from the inside to the outside in the radial direction (from the R2 side to the R1 side) and is stored in the chamber portion 34. The liquid also flows into the external communication hole portion 33 and is supplied to the rotor core flow passage 22. The refrigerant supplied to the rotor core flow passage 22 is discharged to the outside through the flow passage 61 of the liquid discharge plate 6.

[0079] (Regarding the force applied to the end plate) The force acting on the end plate 3 will be described with reference to FIG.

[0080] As shown in FIG. 8, when the rotor 10 (rotor shaft 1) rotates, a force (centrifugal force) F1 directed radially outward is applied to the liquid. Therefore, the liquid is pushed radially outward (toward R1). Furthermore, the liquid in the chamber portion 34 is pushed radially outward by the liquid newly supplied from the rotor shaft 1. The chamber portion 34 is configured so that the liquid does not leak outward in the axial direction by the inner peripheral end surface portion 32a of the second member 32, so that the liquid pushed by the force F1 flows radially outward. The liquid flowing radially outward collides with the radial inner end surface 32e of the chamber portion 34, and the liquid in the chamber portion 34 presses the first member 31 toward the rotor core 2 against the force of the return direction force applying portion 31d. As a result, the force F1 is dispersed into an axial force F2 and a reaction force F3 of the force F2. The forces F2 and F3 increase as the rotation speed (centrifugal force) of the rotor 10 increases.

[0081] Furthermore, fixing force F5 applied by fixing member 5 is a force directed toward the Z1 side in the axial direction, and the application of force F5 presses rotor core 2 toward first member 31. Furthermore, force F4 directed toward the Z2 side in the axial direction is generated by flange portion 14. This makes it possible to maintain the contact state between rotor core 2 and end plate 3.

[0082] A configuration in which the magnetic body 31c short-circuits the permanent magnet 15 will be described with reference to Figures 9 and 10. A force F2 is generated by the centrifugal force F1, which presses the first member 31 toward the rotor core 2. Meanwhile, a force F6 directed axially away from the rotor core 2 is applied to the first member 31 from the return direction force application portion 31d (the first member 31 is biased). Note that in Figures 9 and 10, the magnetic flux emanating from the permanent magnet 15 is indicated by dashed arrows.

[0083] 9, when the force F2 is smaller than the force F6, the first member 31 is located at the initial position. In this case, the magnetic body 31c is separated from the permanent magnet 15, so that no short circuit of the magnetic flux occurs.

[0084] As shown in FIG. 10, the return direction force applying portion 31d is deformed by being pressed toward the rotor core 2 by the force F2. The force F6 gradually increases with the deformation of the return direction force applying portion 31d. When the rotation speed of the rotor 10 increases and reaches a predetermined rotation speed, the force F2 exceeds the force F6, and the first member 31 moves to the operating position. This causes the magnetic body 31c to come into contact with the permanent magnet 15, causing a short circuit of the magnetic flux. In other words, a part of the magnetic flux flowing toward the stator 20 at a position close to the magnetic body 31c does not flow toward the stator 20, but flows to the magnetic body 31c. As a result, the magnetic flux density decreases, and it is possible to prevent the induced voltage from becoming larger than the drive voltage. When the first member 31 comes into contact with the rotor core 2, the force F6 becomes a maximum value, and the deformation of the return direction force applying portion 31d stops. After the first member 31 and the rotor core 2 come into contact with each other, the sum of force F6 and the reaction force caused by the rotor core 2 being pressed by the first member 31 (reaction force against F2) becomes equal to force F2, so that the movement of the first member 31 stops.

[0085] When the rotation of the rotor 10 is weakened, the rotation speed decreases. Then, when the rotation speed falls below a predetermined rotation speed, the force F2 becomes smaller than the force F6, and the return direction force application portion 31d urges the first member 31 toward the second member 32, and the first member 31 returns to the initial position. This reduces the amount of magnetic flux that is short-circuited.

[0086] (Effects of this embodiment) In this embodiment, the following effects can be obtained.

[0087] In this embodiment, as described above, the end plate 3 is arranged close to the rotor core 2 and is movable between an initial position in the axial direction when the rotor core 2 stops rotating and an operating position in the axial direction when the rotor core 2 rotates at a predetermined rotation speed or more, and includes a first member 31 at least partly made of a magnetic material, a second member 32 arranged farther from the rotor core 2 than the first member 31, a flow path space 30 formed between the first member 31 and the second member 32 through which liquid can flow, a return direction force applying portion 31d that applies a biasing force or a suction force to the first member 31 in a direction returning the first member 31 from the operating position to the initial position, and a chamber portion 34 that is a part of the flow path space 30 and is provided on the radial outer side of the end plate 3 and that stores liquid. As a result, a centrifugal force directed radially outward is applied to the liquid in the chamber portion 34 due to the rotation of the rotor 10. In addition, the liquid located at the outer circumferential end of the chamber portion 34 cannot flow radially outward from the chamber portion 34, so that the radial centrifugal force applied to the liquid is dispersed into an axial force. As a result, when the centrifugal force increases as the rotation speed of the rotor 10 reaches or exceeds a predetermined rotation speed, and when the axial force toward the rotor core 2 caused by the centrifugal force becomes greater than the biasing force or attractive force of the return direction force imparting unit 31d, the first member 31 is pushed toward the rotor core 2 by the liquid in the chamber unit 34, so that the first member 31 moves toward the rotor core 2 and the magnetic body 31c can be brought closer to the permanent magnets 15 of the rotor core 2. When the centrifugal force decreases as the rotation speed of the rotor core 2 falls below a predetermined rotation speed, and the axial force toward the rotor core 2 caused by the centrifugal force becomes smaller than the biasing force or attractive force of the return direction force imparting unit 31d, the first member 31 is biased toward the second member 32 by the return direction force imparting unit 31d, so that the first member 31 moves to the initial position and the magnetic body 31c can be separated from the permanent magnets 15 of the rotor core 2. Furthermore, unlike the case where a moving element and a cam member are provided and the magnetic body is moved by coordinating the movement of the moving element with the movement of the cam member, the magnetic body 31c is moved simply by moving the first member 31 in the axial direction by the force toward the rotor core 2 resulting from the centrifugal force, or the biasing force or attractive force of the return direction force imparting portion 31d, which is composed of a first member 31 and a second member 32.Therefore, since there is no need to provide an inclined surface on the first member 31 for sliding against another member, there is no difference caused over time between the inclination angle of the inclined surface of the first member 31 and the inclination angle of the surface of the other member, and no difference caused between the surface roughness of the inclined surface of the first member 31 and the surface roughness of the other member, and it is possible to suppress the generation of a force that resists the biasing force or attractive force of the return direction force applying part 31d. As a result, the first member 31 can be easily moved by the biasing force or attractive force of the return direction force applying part 31d, so that when rotation is stopped or the number of rotations is less than a predetermined number, the magnetic body 31c can be easily moved to the initial position.

[0088] In this embodiment, as described above, the magnetic body 31c is provided on the first member 31 on the rotor core side surface of the first member so as to be able to come into contact with the permanent magnet when the first member 31 is moved to the operating position, and the return direction force application part 31d is arranged at a position separated from the permanent magnet 15 in a direction perpendicular to the axial direction. As a result, when the first member 31 is moved to the operating position, the magnetic body 31c can be brought into contact with the permanent magnet 15, so that a short circuit of the magnetic flux can be reliably generated. In addition, since the return direction force application part 31d is arranged at a position separated from the permanent magnet 15 so as not to come into contact with the permanent magnet 15, it is possible to prevent the return direction force application part 31d from coming into contact with the permanent magnet 15. As a result, when the return direction force application part 31d is arranged in a state of contact with the rotor core 2 and is made of a metal spring member or magnet, it is possible to prevent the return direction force application part 31d from coming into contact with the permanent magnet 15 of the rotor core 2 regardless of the rotation speed of the rotor 10, and to prevent a short circuit of the magnetic flux caused by the return direction force application part 31d.

[0089] In this embodiment, as described above, the return direction force application portion 31d includes a spring member that elastically deforms so that the first member 31 approaches the operating position as the rotation speed of the rotor core 2 increases, and returns to its original elastically deformed state so that the first member 31 approaches the initial position as the rotation speed of the rotor core 2 decreases. This allows the first member 31 to be moved between the initial position and the operating position using the spring member, thereby simplifying the structure compared to the conventional case in which a cam member and a mover having an inclined surface are provided.

[0090] In this embodiment, as described above, the first member 31 is configured to move to the operating position when the force pressing the first member 31 toward the rotor core 2, which is generated by the centrifugal force when the rotor core 2 rotates, is greater than the return direction force of the return direction force application part 31d. As a result, when the rotation speed of the rotor 10 becomes greater than a predetermined value of rotation speed and the force pressing the first member 31 toward the rotor core 2, which is generated by the centrifugal force when the rotor 10 rotates, becomes greater than a predetermined magnitude, the first member 31 moves to the operating position, so that the magnetic body 31c can cause a short circuit of the magnetic flux of the permanent magnet 15. Also, when the rotation speed of the rotor 10 is equal to or less than a predetermined rotation speed and the force pressing the first member 31 toward the rotor core 2, which is generated by the centrifugal force when the rotor 10 rotates, becomes equal to or less than a predetermined magnitude, the first member 31 moves to the initial position, so that the magnetic body 31c can prevent a short circuit of the magnetic flux of the permanent magnet 15 from occurring.

[0091] In this embodiment, as described above, the first member 31 includes the arrangement recess 31e that is provided on the surface 31f facing the rotor core 2 and that houses the return direction force applying portion 31d. As a result, the provision of the arrangement recess 31e allows the return direction force applying portion 31d to be housed within the first member 31, and therefore the axial size of the first member 31 can be reduced, unlike the case where the return direction force applying portion 31d is provided on the surface 31f facing the rotor core 2 of the first member 31. As a result, the axial size of the entire end plate 3 can be prevented from becoming large.

[0092] In this embodiment, as described above, the spring member includes a leaf spring. As a result, since the size (length) of the leaf spring in the direction of elastic deformation is smaller than that of a coil spring, when the leaf spring is provided in the first member 31 with the direction of elastic deformation aligned with the axial direction, it is possible to prevent the size (length) of the first member 31 from becoming large in the axial direction.

[0093] In this embodiment, as described above, a plurality of leaf springs are arranged at predetermined angular intervals in the circumferential direction. As a result, by arranging the leaf springs at predetermined angular intervals in the circumferential direction, the biasing force of the leaf springs can be applied to the entire first member 31, so that the first member 31 can be moved stably. Furthermore, by arranging a plurality of leaf springs, the biasing force that moves the first member 31 from the actuated position to the initial position can be increased, so that the first member 31 can be more easily returned from the actuated position to the initial position.

[0094] In this embodiment, as described above, the first member 31 is entirely made of the magnetic body 31c, or a part of the surface 31f on the rotor core 2 side is made of the magnetic body 31c. As a result, when the first member 31 is entirely made of the magnetic body 31c, the permanent magnet 15 and the magnetic body 31c can be reliably contacted with each other, so that a short circuit of the magnetic flux can be reliably generated. Also, when a part of the first member 31 is made of the magnetic body 31c, the parts other than the magnetic body 31c can be made of a material that is lighter than the magnetic body 31c, so that the weight of the first member 31 can be reduced. As a result, unlike when the weight of the first member 31 is large, the first member 31 can be easily returned to the initial position by the biasing force or attractive force in the return direction by the return direction force applying part 31d.

[0095] In this embodiment, as described above, the first member 31 and the second member 32 are configured to be relatively movable in the axial direction while maintaining contact with each other, and the liquid flowing radially outward collides with the radial inner end surface 32e of the chamber portion 34, so that the liquid in the chamber portion 34 presses the first member 31 toward the rotor core 2 against the force of the return direction force imparting portion 31d. As a result, the first member 31 and the second member 32 are configured to be relatively movable in the axial direction while maintaining contact with each other, so that the first member 31 can be moved without leaking the liquid in the chamber portion 34 to the outside. In addition, the liquid flowing radially outward collides with the radial inner end surface 32e of the chamber portion 34, so that the liquid in the chamber portion 34 presses the first member 31 toward the rotor core 2 against the force of the return direction force imparting portion 31d, so that there is no need to provide a separate drive source for moving the first member 31 to the operating position. As a result, the structure of the rotor 10 can be prevented from becoming complicated.

[0096] In this embodiment, as described above, the first member 31 is annular. This allows the chamber portion 34 to be annular, so that by supplying liquid to a portion of the chamber portion 34, the liquid flows along the outer periphery, and the liquid can be supplied to the entire chamber portion 34. In addition, the centrifugal force caused by the rotation of the rotor 10 can be evenly applied to the liquid in the chamber portion 34, so that the force generated by the centrifugal force pressing the first member 31 toward the rotor core 2 can be evenly applied to the first member 31.

[0097] In this embodiment, as described above, the seal member 4 is provided at the portion where the first member 31 and the second member 32 contact each other. This can further prevent the liquid in the chamber from leaking to the outside.

[0098] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims, not by the description of the embodiments above, and further includes all modifications (variations) within the meaning and scope of the claims.

[0099] For example, in the above embodiment, an example has been shown in which the rotor core 2 is provided with the rotor core flow passage 22, but the present invention is not limited to this. In the present invention, the rotor core flow passage 22 does not have to be provided. In this case, as in a rotor 210 of a first modified example shown in FIG. 11 , the external communication hole portion 33 may be provided in the second member 32, and the coolant in the chamber portion 34 may be discharged to the outside of the end plate 3.

[0100] For example, in the above embodiment, the seal member 4 is provided on the first member, but the present invention is not limited to this. In the present invention, the seal member may be provided on the second member.

[0101] In the above embodiment, the first member 31 has a flat plate shape extending in the radial direction, but the present invention is not limited to this. In the present invention, as in a rotor 310 of a second modified example shown in FIG. 12, the first member 31 may have a stepped portion 36 formed at the radial outer end portion, the stepped portion 36 having an axial length smaller than other portions. In this case, the second member 32 is configured to contact the radial outer peripheral surface 36a and the axial end surface 36b of the first member 31, which form the stepped portion 36.

[0102] Also, as in a rotor 310 of a second modified example shown in FIG. 12, in the present invention, the liquid discharge plate 6 may have a configuration similar to that of the end plate 3. In this case, the liquid discharge plate 6 includes a flow path 61, which is an external communication hole portion, a first member 63, and a second member 64. The first member 63 and the second member 64 form a chamber portion 65. In this case, the liquid discharge plate may be supplied with a coolant from the rotor shaft, for example, or may be supplied with liquid from outside the rotating electric machine 100. Also, the liquid discharge plate 6 is configured to maintain a contact state between the liquid discharge plate 6 and the rotor core 2 by liquid collecting in the chamber portion 65, similar to the end plate 3.

[0103] In the above embodiment, the flow passages 61 of the liquid discharge plate 6 extend along the axial direction, but the present invention is not limited to this. In the present invention, the flow passages 61 may be configured to incline from the inner periphery side to the outer periphery side in the radial direction as they move away from the rotor core 2, as in a rotor 410 of a third modified example shown in FIG.

[0104] In the above embodiment, the seal member 4 is provided on the end plate 3, but the present invention is not limited to this. In the present invention, as in a rotor 510 of a fourth modified example shown in Fig. 14, the seal member 4 may not be provided, but a convex portion 37 may be provided on the outer peripheral end face 31b of the first member 31, a concave portion 38 may be provided on the corresponding inner surface in the radial direction of the second member 32, and the convex portion 37 may be fitted into the concave portion 38 to provide sealing. In this case, the convex portion 37 may be configured to be smaller than the concave portion 38, and a gap may be provided that allows the convex portion 37 to move axially, thereby allowing the first member 31 and the second member 32 to move relatively to each other.

[0105] In the above embodiment, an example has been described in which liquid is supplied from the rotor shaft 1 to the end plate 3, but the present invention is not limited to this. Liquid may be supplied from a liquid supply source external to the rotating electric machine to the inside of the end plate through the external communication hole. In this case, the external communication hole is used to supply the liquid. Furthermore, the external communication hole is provided in the second member.

[0106] In the above embodiment, the external communication hole 33 is configured to discharge liquid to the outside, but the present invention is not limited to this. The external communication hole 33 may be configured to discharge liquid to the outside and supply liquid to the inside. For example, the external communication hole 33 may be used to supply liquid when the rotor is rotating and to discharge liquid when the rotor is stopped. In this case, the second member may be provided with an external communication hole that serves both as a supply hole and a discharge hole.

[0107] In the above embodiment, the end plate 3 includes the first member 31 and the second member 32, but the present invention is not limited to this. The end plate 3 may include a third member in addition to the first member and the second member. In this case, the third member may be configured to divide the chamber portion in the axial direction.

[0108] In the above embodiment, the external communication hole portions 33 and the flow path forming portions 32c are arranged at equal angular intervals, but the present invention is not limited to this. The external communication hole portions and the flow path forming portions may be arranged irregularly.

[0109] Furthermore, the combination of the end plate 3 and the liquid discharging plate 6 shown in the above embodiment and modified example is just one example, and for example, the end plate of the embodiment may be combined with the liquid discharging plate of the modified example.

[0110] In the above embodiment, the permanent magnet 15 is disposed on the inner periphery side close to the central axis C of rotation, but the present invention is not limited to this. The permanent magnet may be disposed on the outer periphery side away from the central axis C of rotation. In this case, the magnetic body is also disposed on the outer periphery side, and the return direction force applying portion is disposed on the inner periphery side of the magnetic body.

[0111] In the above embodiment, the return direction force applying portion 31d applies a biasing force to the first member 31, but the present invention is not limited to this. The return direction force applying portion may apply an attractive force to the first member to attract the first member toward the second member side (the side opposite to the rotor core). In this case, the return direction force applying portion may be composed of, for example, a magnet. In this case, a magnet serving as the return direction force applying portion may be provided on both the first member and the second member, or a magnet serving as the return direction force applying portion may be provided on either the first member or the second member.

[0112] In the above embodiment, the return direction force applying portion 31d is a leaf spring, but the present invention is not limited to this. The return direction force applying portion may be a spring member other than a leaf spring. In this case, the return direction force applying portion may be, for example, a linear spring or a disc spring.

[0113] In the above embodiment, the magnetic body 31c is provided in a portion of the first member 31, but the present invention is not limited to this. The entire first member may be made of a magnetic body.

[0114] In the above embodiment, the magnetic body 31c is disposed on a portion of the surface of the first member 31 facing the rotor core 2, but the present invention is not limited to this. The magnetic body may be disposed on the entire surface of the first member facing the rotor core.

[0115] In the above embodiment, an example has been shown in which the return direction force applying portion 31d is arranged by providing the arrangement recess 31e on the surface 31f of the first member 31 facing the rotor core 2, but the present invention is not limited to this. The return direction force applying portion may be arranged on the surface of the first member facing the rotor core without providing a placement recess. [Explanation of symbols]

[0116] 1 rotor shaft 2 Rotor core 3 End Plate 10, 210, 310, 410, 510 rotor 15 Permanent magnets 21 Shaft insertion hole 30 Flow passage space 31 First member 31c magnetic material 31d Return direction force applying part 31f Rotor core side 32 Second member 34 Chamber section

Claims

1. A rotor shaft rotatable about an axis; A rotor core including a permanent magnet fixed to the rotor shaft and extending in the axial direction; an end plate disposed on an end face side of the rotor core in the axial direction, The end plate is a first member at least a portion of which is made of a magnetic material, the first member being disposed adjacent to the rotor core and movable between an initial position in the axial direction when rotation is stopped and an operating position in the axial direction when rotation is at least a predetermined rotation speed and which is closer to the rotor core than the initial position; A second member disposed farther away from the rotor core than the first member; A flow path space formed between the first member and the second member, through which a liquid can flow; a return direction force application unit that applies a biasing force or an attractive force to the first member in a direction to return the first member from the operating position to the initial position; a chamber portion that is a part of the flow path space and is provided on a radially outer side of the end plate, the chamber portion storing liquid.

2. the magnetic body is provided on the first member on a surface of the first member facing the rotor core so as to be capable of contacting the permanent magnet when the first member is moved to the operating position; The rotor according to claim 1 , wherein the return direction force application portion is disposed at a position separated from the permanent magnet in a direction perpendicular to the axial direction and does not contact the permanent magnet.

3. 2. The rotor according to claim 1, wherein the return direction force imparting portion includes a spring member that elastically deforms so that the first member approaches the operating position as the rotation speed of the rotor core increases, and that returns to its original elastically deformed state so that the first member approaches the initial position as the rotation speed of the rotor core decreases.

4. 2. The rotor according to claim 1, wherein the first member is configured to move to the operating position when a force pressing the first member toward the rotor core, which is generated by a centrifugal force when the rotor core rotates, is greater than a return direction force of the return direction force application portion.

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