rotor

Abstract

To provide a rotor capable of realizing a simplified device configuration in which a plurality (two) of end plates is not provided on one side in an axial direction as the device configuration for making a refrigerant flow in a core flow passage of a rotor core extending in the axial direction.SOLUTION: A rotor 102 includes: a rotor shaft 1 provided with a hollow section 10; a rotor core 2 including a core flow passage 23 extending in an axial direction; an end plate 3 including an inside end surface 30 in contact with the rotor core 2 and an outside end surface 31; a fixing member 4 including an end plate contact surface 40 and regulating movement of the end plate 3; and a supply flow passage 5 for supplying a refrigerant from the hollow section 10 to the core flow passage 23. The supply flow passage 5 includes a boundary flow passage 52 extending along a boundary between the outer end surface 31 and the end plate contact surface 40.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a rotor. [Background technology]

[0002] BACKGROUND ART Conventionally, a rotor provided with a flow path through which a refrigerant flows is known (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses a rotor including a rotor shaft having a hollow portion through which a coolant is supplied, a rotor core provided with a cooling passage extending in the axial direction through which the coolant flows, and two end plates provided at one axial end of the rotor core and in contact with each other. The rotor core has magnet holes in which permanent magnets are disposed radially outside the cooling passages. A passage is provided at the boundary between the two end plates to guide the coolant from the hollow portion of the rotor shaft to the cooling passage of the rotor core. The rotor also includes a movement restriction portion that contacts the axially outer end plate and restricts axial movement of the two end plates and the rotor core. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-120425 Summary of the Invention [Problem to be solved by the invention]

[0005] In the rotor described in Patent Document 1, two (or more) end plates whose axial movement is restricted by a movement restriction portion are required to guide the refrigerant in the hollow portion of the rotor shaft into the cooling passage of the rotor core, and it is desirable to simplify the device configuration for flowing the refrigerant into the cooling passage of the rotor core extending in the axial direction.

[0006] This invention has been made to solve the above-mentioned problems, and one object of this invention is to provide a rotor that can have a simplified device configuration for flowing refrigerant through a core flow path of a rotor core extending in the axial direction, without having multiple (two) end plates on one side in the axial direction. [Means for solving the problem]

[0007] In order to achieve the above object, a rotor according to one aspect of the present invention comprises: a rotor core including a rotor shaft extending in an axial direction and having a hollow portion through which a refrigerant is supplied, a shaft insertion hole into which the rotor shaft is inserted, and a core flow passage extending in the axial direction through which the refrigerant flows; end plates including an inner end face in contact with one axial end face of the rotor core and an outer end face axially opposite the inner end face; an axial movement restricting portion provided separately from the end plates and including an end plate contact surface in contact with the outer end face of the end plate, the axial movement restricting portion contacting the outer end face to restrict axial movement of the end plates and the rotor core relative to the rotor shaft by contacting the outer end face; and a supply flow passage that supplies refrigerant from the hollow portion to the core flow passage, the supply flow passage including: a boundary flow passage extending along the boundary between the outer end face of the end plate and the end plate contact surface of the axial movement restricting portion; a first connecting flow passage provided in the rotor shaft and connecting the hollow portion and the boundary flow passage; and a second connecting flow passage provided in the end plate and connecting the boundary flow passage and the core flow passage. The boundary flow path is configured to connect the first connecting flow path and the second connecting flow path. .

[0008] As described above, a rotor according to one aspect of the present invention includes an axial movement restricting portion that restricts axial movement of the end plates and the rotor core relative to the rotor shaft, and a supply passage that supplies refrigerant from the hollow portion to the core passage. The supply passage includes a boundary passage that extends along the boundary between the outer end surface of the end plate and the end plate contact surface of the axial movement restricting portion, a first connecting passage that is provided in the rotor shaft and connects the hollow portion to the boundary passage, and a second connecting passage that is provided in the end plate and connects the boundary passage to the core passage. This makes it possible to form the boundary passage of the supply passage that introduces refrigerant from the hollow portion of the rotor shaft to the core passage extending in the axial direction of the rotor core using a single end plate and an existing axial movement restricting portion. This allows the number of end plates on one axial side to be reduced from two compared to conventional rotors, thereby simplifying the device configuration for flowing refrigerant into the axially extending core passage of the rotor core by not requiring multiple (two) end plates on one axial side.

[0009] In the rotor core according to the above aspect, preferably, the length from the outer peripheral surface of the rotor shaft to the outer peripheral surface of the axial movement restricting portion in the radial direction of the rotor core is shorter than half the length from the outer peripheral surface of the rotor shaft to the outer peripheral surface of the rotor core. This configuration allows the contact area of ​​the axial movement restricting portion with the rotor core to be relatively small, thereby allowing the contact pressure of the axial movement restricting portion with the rotor core to be relatively large. As a result, refrigerant leakage from the boundary flow passage extending along the boundary between the axial movement restricting portion (end plate contact surface) and the end plate (outer end surface) can be effectively suppressed.

[0010] In the rotor core according to the above aspect, preferably, the end plates include grooves recessed from their outer end faces toward the rotor core, and the boundary flow passages are formed by the grooves and the end plate contact surfaces of the axial movement restricting parts. With this configuration, it is not necessary to provide a structure for forming the boundary flow passages on the end plate contact surfaces of the axial movement restricting parts. Therefore, unlike when grooves are provided in both the axial movement restricting parts and the end plates, it is possible to eliminate the step of aligning the grooves of the axial movement restricting parts and the end plates including the grooves.

[0011] In the rotor core according to the above aspect, the axial movement restricting portion is preferably a fixed member that is fixed to the rotor shaft and thereby positioned in the axial direction, and a set of an end plate and a fixed member is provided on both one and the other axial sides of the rotor core. With this configuration, the one and the other axial sides of the rotor core can have a common configuration, thereby simplifying the configuration of the device for cooling the rotor.

[0012] In the rotor core according to the above aspect, the rotor core preferably includes magnet holes in which permanent magnets are arranged and slits formed by through holes provided radially inside the magnet holes and extending in the axial direction of the rotor core, and the core flow passage through which the refrigerant flows is formed by the slits. Here, the slits formed by the through holes extending in the axial direction of the rotor core expand radially when the rotor is driven, thereby maintaining the position of the rotor core at the radially inner portion of the slits and slightly shifting the position of the rotor core at the radially outer portion of the slits radially outward. As a result, the slits maintain contact between the rotor core and the rotor shaft even when centrifugal force is applied to the rotor core. Therefore, with the above configuration, the slits can be used as the core flow passage while maintaining contact between the rotor core and the rotor shaft.

[0013] The rotor core according to the above aspect preferably further includes a discharge member including a discharge passage that discharges the coolant supplied from the supply passage on one axial side of the rotor core from the other axial side, and the discharge passage includes an inclined surface that is inclined toward the coil end portion of the stator so that the discharged coolant is discharged toward the coil end portion of the stator. With this configuration, the inclined surface allows the coolant to be discharged toward the coil end portion of the stator, so that not only the rotor but also the coil end portion of the stator can be cooled.

[0014] In the rotor according to the above aspect, the following configuration is also possible.

[0015] (Additional note 1) In the above-described configuration in which the rotor core includes slits, the slits preferably include inner slits and outer slits that are provided radially outward of the inner slits and are positioned closer to the magnet holes than the inner slits, and the core flow passage through which the refrigerant flows is formed by the outer slits. With this configuration, the refrigerant can flow through the outer slits that are positioned closer to the magnet holes that are positioned radially outward of the inner slits, thereby effectively cooling the heat-generating permanent magnets.

[0016] (Additional note 2) In the configuration in which the above-mentioned sets of end plates and fixing members are provided on both one axial side and the other axial side of the rotor core, preferably, the supply flow passage provided in the set of end plates and fixing members on one axial side of the rotor core is configured to supply the refrigerant to the rotor core from one axial side of the rotor core and flow the refrigerant toward the other axial side of the rotor core, and the supply flow passage provided in the set of end plates and fixing members on the other axial side of the rotor core is configured to supply the refrigerant to the rotor core from the other axial side of the rotor core and flow the refrigerant toward one axial side of the rotor core. With this configuration, the refrigerant can flow in both axial directions, thereby enabling balanced and even cooling of the rotor core.

[0017] (Additional note 3) In the above-described configuration in which the end plate includes a groove, the groove forming the boundary flow passage preferably includes an annular groove extending annularly along the outer circumferential surface of the rotor shaft and a plurality of radial grooves extending radially outward from the annular groove. With this configuration, the annular groove can easily disperse the refrigerant in the circumferential direction, and the radial grooves can easily direct the refrigerant dispersed in the circumferential direction toward the radially outward direction. As a result, the rotor core can be cooled uniformly in both the circumferential and radial directions.

[0018] (Additional note 4) In this case, preferably, a first connection flow path is connected to the annular groove from the radially inner side, and a second connection flow path is connected to the radially outer end of the radial groove from the rotor core side. With this configuration, the first connection flow path allows the refrigerant to easily flow from the hollow portion of the rotor shaft to the annular groove, and the second connection flow path allows the refrigerant to easily flow from the radial groove to the core flow path of the rotor core. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a cross-sectional view of a rotating electrical machine including a rotor according to an embodiment, viewed from a radial direction; [Figure 2] FIG. 2 is a view taken along the line II-II in FIG. [Figure 3] FIG. 2 is an enlarged view of part A in FIG. [Figure 4] FIG. 2 is an exploded perspective view of a rotor according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0021] A rotor 102 of this embodiment provided in a rotating electrical machine 100 will be described with reference to FIGS.

[0022] In each drawing, the direction in which the rotor shaft 1 extends (axial direction) is indicated by the Z direction. The "axial direction" is also the direction along the central axis C of rotation of the rotor core 2.

[0023] In each drawing, the radial direction of the rotor core 2 is indicated by the R direction. The radially outer side is indicated by the R1 direction, and the radially inner side is indicated by the R2 direction. The R direction is also the radial direction of the end plate (an example of an "exhaust member" in the claims) 3, the fixed member (an example of an "axial movement restricting portion" in the claims) 4, and the rotor shaft 1.

[0024] In each drawing, the circumferential direction of the rotor core 2 is indicated by the r direction. The r direction is also the circumferential direction of the end plates 3, the fixing members 4, and the rotor shaft 1.

[0025] As shown in Fig. 1, the rotating electric machine 100 includes a stator 101 and a rotor 102. The stator 101 and the rotor 102 face each other. The rotor 102 is disposed radially inside (on the R2 direction side) the stator 101. That is, the rotating electric machine 100 of this embodiment is configured as an inner rotor type rotating electric machine.

[0026] (Stator configuration) The stator 101 includes a stator core 101a and a coil 101b arranged on the stator core 101a.

[0027] At both axial ends of the stator core 101a, coil end portions 101c of the coils 101b are provided, protruding in the axial direction from the stator core 101a. The stator core 101a is made up of a plurality of electromagnetic steel plates stacked in the axial direction, and is configured to allow magnetic flux to pass through. The coils 101b are connected to an external power supply and configured to receive power (e.g., three-phase AC power). When power is supplied to the coils 101b, they are configured to generate a magnetic field.

[0028] (Rotor configuration) The rotor 102 includes a rotor shaft 1, a rotor core 2, end plates 3, a fixing member 4, and a supply flow path 5.

[0029] The end plate 3 is a single structure provided on one axial side (one side) of the rotor core 2. The end plate 3 is a single structure provided on the other axial side (one side) of the rotor core 2.

[0030] The end plates 3 and the fixing members 4 are arranged in contact with each other in the axial direction. Sets of end plates 3 and fixing members 4 are provided on both axial sides of the rotor core 2. The sets of end plates 3 and fixing members 4 are configured as a pair. The supply flow paths 5 are configured so that the rotor 102 supplies refrigerant to the rotor core 2 from the supply flow paths 5 on both axial sides, allowing the refrigerant to flow in both axial directions.

[0031] Specifically, the rotor 102 is configured such that the fixing member 4, end plate 3, rotor core 2, end plate 3, and fixing member 4 are arranged in this order in the axial direction. The rotor shaft 1 is inserted through the fixing member 4, end plate 3, and rotor core 2.

[0032] The set of end plates 3 and fixing members 4 on the Z1 direction side and the set of end plates 3 and fixing members 4 on the Z2 direction side are arranged at a predetermined angle in the circumferential direction. More specifically, when viewed from the axial direction, the set of end plates 3 and fixing members 4 on the Z1 direction side and the set of end plates 3 and fixing members 4 on the Z2 direction side are arranged at a predetermined angle so that second connection flow paths 51 (described later) do not overlap with each other.

[0033] As an example, the set of end plate 3 and fixing member 4 on the Z1 side and the set of end plate 3 and fixing member 4 on the Z2 side are arranged 45 degrees apart in the circumferential direction.

[0034] The rotor core 2 is made up of multiple electromagnetic steel plates stacked in the axial direction and is configured to allow magnetic flux to pass through. The rotor core 2 includes multiple magnet holes 20 in which permanent magnets 20a are arranged. The magnet holes 20 are arranged at predetermined angular intervals near the outer peripheral surface 2a on the radially outer side (R1 direction side) of the rotor core 2. The magnet holes 20 penetrate the rotor core 2 in the axial direction.

[0035] The rotating electric machine 100 is configured as an interior permanent magnet motor (IPM motor). The multiple permanent magnets 20a form multiple magnetic poles M arranged circumferentially. The rotor 102 is configured so that when the rotating electric machine 100 is driven, the permanent magnets 20a, which generate heat, are cooled by a refrigerant flowing through the rotor 102.

[0036] (Configuration of rotor shaft of rotor) The rotor shaft 1 is a shaft portion that serves as the center of rotation of the rotating electrical machine 100. The rotor shaft 1 is formed in a cylindrical (annular) shape having a circular outer circumferential surface 1a. As an example, the rotor shaft 1 is formed from steel.

[0037] The rotor shaft 1 is provided with a hollow portion 10 and a first connecting passage 50 that forms part of the supply passage 5.

[0038] The hollow portion 10 is formed by a hole extending along the central axis of rotation C that extends in the axial direction (Z direction) of the rotor shaft 1. The hollow portion 10 is the location where the refrigerant is first supplied in each component of the rotor 102. The hollow portion 10 is configured so that the refrigerant is sent from a refrigerant supply source (not shown) that stores the refrigerant.

[0039] The first connection flow passage 50 is formed by a through-hole for allowing the refrigerant to flow from the hollow portion 10 to the outside of the rotor shaft 1. The first connection flow passage 50 extends linearly in the radial direction (direction R). A plurality of first connection flow passages 50 are provided in the circumferential direction (direction r). As an example, two first connection flow passages 50 are provided at equal angular intervals in the circumferential direction (direction r). Two first connection flow passages 50 are provided on one side and two on the other side in the axial direction of the rotor shaft 1 (a total of four). A radially inner end of the first connection flow passage 50 is connected to the hollow portion 10. A radially outer end of the first connection flow passage 50 is connected to a boundary flow passage 52 (annular groove portion 32a) that forms part of the supply flow passage 5.

[0040] (Structure of rotor core) As shown in Figures 1 and 2, the rotor core 2 includes the magnet holes 20, the shaft insertion holes 21 into which the rotor shaft 1 is inserted, slits 22, and core flow paths 23 extending in the axial direction through which the refrigerant flows.

[0041] The shaft insertion hole 21 is formed by a circular hole portion disposed in the center of the rotor core 2. Therefore, the rotor core 2 is formed in a cylindrical (annular) shape having a circular outer peripheral surface 2a.

[0042] The slits 22 are provided radially inside the magnet holes 20. The slits 22 are formed by through holes extending in the axial direction of the rotor core 2. The slits 22 are disposed near the inner circumferential surface on the radially inside (R2 direction side) of the rotor core 2. The slits 22 form core flow paths 23 through which the refrigerant flows.

[0043] More specifically, the slits 22 have an inner slit 22a and an outer slit 22b. The outer slit 22b is provided radially outward of the inner slit 22a and is positioned closer to the magnet hole 20 than the inner slit 22a. In other words, the outer slit 22b is positioned radially closer to the heat-generating permanent magnet 20a than the inner slit 22a.

[0044] The core flow passage 23 through which the refrigerant flows is formed by the outer slit 22b. That is, the outer slit 22b (core flow passage 23) is connected to the hollow portion 10 of the rotor shaft 1 via a supply flow passage 5 on one axial side. The outer slit 22b (core flow passage 23) is also configured to discharge the refrigerant to the outside of the rotor 102 via a discharge flow passage 33 on the other axial side.

[0045] On the other hand, both axial ends of the inner slit 22a are closed by the end plate 3 (inner end surface 30), so that the refrigerant does not flow through the inner slit 22a.

[0046] (Rotor end plate configuration) As described above, a pair of end plates 3 are provided to sandwich the rotor core 2 from both sides in the axial direction. The end plates 3 are thin-walled circular plate members that are smaller in axial size than the rotor core 2. The radius L10 of the end plates 3 is larger than the radius L11 of the fixing member 4 (see FIG. 1). The radius L10 of the end plates 3 is approximately equal to the diameter L12 of the rotor core 2 (see FIG. 1).

[0047] As shown in FIGS. 1 to 4, the end plate 3 includes an inner end surface 30, an outer end surface 31, a groove 32, and a discharge flow path 33.

[0048] The inner end face 30 is configured to contact one axial end face 2b of the rotor core 2. An end of the core flow passage 23 of the rotor core 2 is disposed on the inner end face 30. The outer end face 31 is disposed on the opposite side of the inner end face 30 in the axial direction. In other words, the outer end face 31 is disposed at a position farther away from the rotor core 2 than the inner end face 30.

[0049] The grooves 32 are recessed from the outer end surface 31 toward the rotor core 2. The grooves 32 are configured to form boundary flow paths 52. Details will be described later.

[0050] The discharge flow passage 33 is configured to discharge the refrigerant supplied from the supply flow passage 5 on one side in the axial direction of the rotor core 2 from the other side in the axial direction.

[0051] The discharge flow passage 33 includes an inclined surface 33a. The inclined surface 33a is inclined toward the coil end portion 101c so that the refrigerant discharged from the discharge flow passage 33 is discharged toward the coil end portion 101c of the stator 101. A plurality of discharge flow passages 33 are provided in the end plate 3. Specifically, four discharge flow passages 33 are provided at equal angular intervals in the circumferential direction (r direction). The discharge flow passages 33 are arranged between the radial groove portions 32b of adjacent supply flow passages 5 in the circumferential direction (r direction). Each discharge flow passage 33 extends radially in the radial direction.

[0052] The exhaust flow passage 33 is disposed at a position where its radially inner end overlaps with the core flow passage 23 of the rotor core 2, and is connected to the core flow passage 23 (outer slit 22b). The exhaust flow passage 33 has its radially outer end connected to the outside of the rotor 102. In detail, the exhaust flow passage 33 includes an exhaust through-hole portion 33b and an exhaust groove portion 33c.

[0053] The discharge through-hole portion 33b is disposed radially inside the discharge flow passage 33 and extends in the axial direction. The discharge through-hole portion 33b is connected to the core flow passage 23 (outer slit 22b).

[0054] Discharge groove 33c extends linearly from discharge through-hole 33b radially outward along the boundary between end plate 3 and fixed member 4. Discharge groove 33c is provided in end plate 3. A radially inner portion of discharge groove 33c is blocked by fixed member 4 (end plate contact surface 40) (see FIG. 3). A radially outer portion of discharge groove 33c is not blocked by fixed member 4 and is open so that refrigerant can be discharged toward rotor 102 (see FIG. 3).

[0055] Therefore, the inclined surface 33a is not blocked by the fixing member 4, and is disposed at a position exposed to the outside of the rotor .

[0056] To summarize the flow of the refrigerant supplied to the discharge flow path 33, the refrigerant flows from upstream to downstream through the discharge through-hole 33b, the discharge groove 33c, the inclined surface 33a, and the outside of the rotor 102 in this order.

[0057] (Configuration of rotor fixing member) The fixing members 4 are provided separately from the end plates 3. The fixing members 4 include end plate contact surfaces 40 that come into contact with the outer end faces 31 of the end plates 3. The fixing members 4 are configured to restrict axial movement of the end plates 3 and the rotor core 2 relative to the rotor shaft 1 by contacting the outer end faces 31 at the end plate contact surfaces 40.

[0058] Specifically, the fixing member 4 is configured to be directly fixed to the rotor shaft 1 and thereby positioned in the axial direction. The fixing member 4 is fixed to the rotor shaft 1 by crimping. The rotor shaft 1 is provided with an annular crimp groove 11 (see FIG. 3) extending in the circumferential direction. As described above, a pair of fixing members 4 are provided so as to sandwich the rotor core 2 from both sides in the axial direction.

[0059] The pair of fixing members 4 are configured to sandwich the end plates 3 and the rotor core 2 and be fixed to the rotor shaft 1 by crimping, thereby restricting axial movement of the end plates 3 and the rotor core 2. Note that instead of crimping, the fixing members may be fixed to the rotor shaft by press fitting or by fastening the inner peripheral surface of the fixing members to the outer peripheral surface of the shaft with a threaded shape.

[0060] In the radial direction of the rotor core 2, the length L1 (see FIG. 1) from the outer peripheral surface 1a of the rotor shaft 1 to the outer peripheral surface 4a of the fixing member 4 is smaller than half the length L2 (see FIG. 1) from the outer peripheral surface 1a of the rotor shaft 1 to the outer peripheral surface 2a of the rotor core 2. In the radial direction of the rotor core 2, the outer peripheral surface 4a of the fixing member 4 is disposed radially outward of the outer ends of the radial grooves 32b of the supply flow passages 5 and in the vicinity of the outer ends of the radial grooves 32b.

[0061] The difference between the fixing member 4 and the end plates 3 is that the fixing member 4 is configured to be directly fixed to the rotor shaft 1, while the end plates 3 are not directly fixed to the rotor shaft 1. In other words, the fixing member 4 itself has the function of determining its axial position relative to the rotor shaft 1, while the end plates 3 themselves do not have the function of determining its axial position relative to the rotor shaft 1.

[0062] (Configuration of rotor supply passage) The supply flow path 5 is configured to supply the refrigerant from the hollow portion 10 of the rotor shaft 1 to the core flow path 23 (outer slit 22b) of the rotor core 2.

[0063] The supply flow path 5 includes a first connecting flow path 50 , a second connecting flow path 51 , and a boundary flow path 52 .

[0064] As described above, the first connection flow passages 50 are provided in the rotor shaft 1 and connect the hollow portion 10 and the boundary flow passages 52. A plurality of first connection flow passages 50 are provided for each supply flow passage 5. As an example, two first connection flow passages 50 are provided for each supply flow passage 5 on one end plate 3 side, spaced apart by an angle of 180 degrees in the circumferential direction. The first connection flow passages 50 are also disposed at positions offset from the radial grooves 32b in the circumferential direction. In other words, the supply flow passages 5 are configured so that the refrigerant is not directly supplied from the first connection flow passages 50 to the radial grooves 32b.

[0065] The second connecting flow passage 51 is provided in the end plate 3 and connects the boundary flow passage 52 and the core flow passage 23. The second connecting flow passage 51 is formed by a through hole extending in the axial direction of the end plate 3.

[0066] The boundary flow path 52 is a flow path that connects the first connecting flow path 50 and the second connecting flow path 51. The boundary flow path 52 extends along the boundary between the outer end surface 31 of the end plate 3 and the end plate contact surface 40 of the fixing member 4.

[0067] More specifically, the boundary flow passage 52 is formed by the groove portion 32 recessed into the rotor core 2 side of the end plate 3 and the end plate contact surface 40 of the fixing member 4. That is, the boundary flow passage 52 is formed by the end plate 3 and the fixing member 4 coming into contact with each other such that the end plate contact surface 40 of the fixing member 4 covers the open portion of the groove portion 32 of the end plate 3.

[0068] The groove portion 32 forming the boundary flow channel 52 has an annular groove portion 32a and a plurality of radial groove portions 32b.

[0069] The annular groove portion 32a extends annularly along the outer peripheral surface 1a of the rotor shaft 1. The plurality of radial groove portions 32b extend radially outward from the annular groove portion 32a. As an example, four of the plurality of radial groove portions 32b are provided at equal angular intervals in the circumferential direction (direction r). In the radial direction of the rotor core 2, the radially outer ends of the radial groove portions 32b of the boundary flow passages 52 are positioned more inward than the radially outer ends of the discharge flow passages 33.

[0070] A first connection flow passage 50 is connected to the annular groove portion 32a from the radially inner side. A second connection flow passage 51 is connected to the radially outer end of the radial groove portion 32b from the rotor core 2 side.

[0071] A supply flow path 5 provided in a set of an end plate 3 and a fixing member 4 on one axial side of the rotor core 2 is configured to supply refrigerant to the rotor core 2 from one axial side of the rotor core 2 and flow the refrigerant toward the other axial side of the rotor core 2.

[0072] To summarize the flow of refrigerant supplied to the rotor core 2 from one axial side of the rotor core 2, the refrigerant flows from upstream to downstream in the following order: hollow portion 10 of the rotor shaft 1, first connecting flow path 50 of the rotor shaft 1, boundary flow path 52, second connecting flow path 51 of the end plate 3, core flow path 23 (outer slit 22b) of the rotor core 2, discharge flow path 33 on the other axial side of the rotor core 2, outside the rotor 102, and coil end portion 101c of the stator 101.

[0073] In addition, a supply flow path 5 provided in a set of an end plate 3 and a fixing member 4 on the other axial side of the rotor core 2 is configured to supply refrigerant to the rotor core 2 from the other axial side of the rotor core 2 and flow the refrigerant toward one axial side of the rotor core 2.

[0074] To summarize the flow of refrigerant supplied to the rotor core 2 from the other axial side of the rotor core 2, the refrigerant flows from upstream to downstream in the following order: hollow portion 10 of the rotor shaft 1, first connecting flow path 50 of the rotor shaft 1, boundary flow path 52, second connecting flow path 51 of the end plate 3, core flow path 23 (outer slit 22b) of the rotor core 2, discharge flow path 33 on one axial side of the rotor core 2, outside of the rotor 102, and coil end portion 101c of the stator 101.

[0075] (Effects of this embodiment) In this embodiment, the following effects can be obtained.

[0076] As described above, this embodiment includes the fixing member 4 that restricts axial movement of the end plate 3 and the rotor core 2 relative to the rotor shaft 1, and the supply flow path 5 that supplies refrigerant from the hollow portion 10 to the core flow path 23. The supply flow path 5 includes a boundary flow path 52 that extends along the boundary between the outer end surface 31 of the end plate 3 and the end plate contact surface 40 of the fixing member 4, a first connection flow path 50 that is provided in the rotor shaft 1 and connects the hollow portion 10 to the boundary flow path 52, and a second connection flow path 51 that is provided in the end plate 3 and connects the boundary flow path 52 to the core flow path 23. This makes it possible to form the boundary flow path 52 of the supply flow path 5 that introduces refrigerant from the hollow portion 10 of the rotor shaft 1 to the core flow path 23 that extends in the axial direction of the rotor core 2 using one end plate 3 and the fixing member 4, which has an existing configuration. As a result, compared to the conventional method, the number of end plates 3 on one side of the axial direction can be reduced from two to one, and the device configuration for flowing refrigerant through the core flow path 23 of the rotor core 2 extending in the axial direction can be simplified by not having multiple (two) end plates 3 on one side of the axial direction.

[0077] In this embodiment, as described above, in the radial direction of the rotor core 2, the length L1 from the outer peripheral surface 1a of the rotor shaft 1 to the outer peripheral surface 4a of the fixed member 4 is shorter than half the length L2 from the outer peripheral surface 1a of the rotor shaft 1 to the outer peripheral surface 2a of the rotor core 2. This allows the contact area of ​​the fixed member 4 with the rotor core 2 to be relatively small, and therefore the contact pressure of the fixed member 4 with the rotor core 2 to be relatively large. As a result, it is possible to effectively prevent refrigerant from leaking from the boundary flow passage 52 extending along the boundary between the fixed member 4 (end plate contact surface 40) and the end plate 3 (outer end surface 31).

[0078] In this embodiment, as described above, the end plate 3 includes the groove portion 32 recessed from the outer end surface 31 toward the rotor core 2, and the boundary flow passage 52 is formed by the groove portion 32 and the end plate contact surface 40 of the fixed member 4. This eliminates the need to provide a configuration for forming the boundary flow passage 52 on the end plate contact surface 40 side of the fixed member 4, and therefore, unlike when the groove portion 32 is provided on both the fixed member 4 and the end plate 3, it is possible to eliminate the step of aligning the groove portions 32 between the fixed member 4 and the end plate 3 including the groove portion 32.

[0079] In this embodiment, as described above, the axial movement restricting portion is the fixed member 4 that is fixed to the rotor shaft 1 and thereby positioned in the axial direction, and a set of the end plate 3 and the fixed member 4 is provided on both one and the other axial sides of the rotor core 2. This allows the configuration of the one and the other axial sides of the rotor core 2 to be standardized, thereby simplifying the configuration of the device for cooling the rotor 102.

[0080] As described above, in this embodiment, the rotor core 2 includes magnet holes 20 in which the permanent magnets 20a are arranged, and slits 22 formed by through-holes that are provided radially inside the magnet holes 20 and extend in the axial direction of the rotor core 2. The core flow passages 23 through which the refrigerant flows are formed by the slits 22. Here, the slits 22 formed by the through-holes extending in the axial direction of the rotor core 2 expand radially during rotation of the rotor 102, thereby maintaining the position of the radially inner portion of the rotor core 2 relative to the slits 22 and slightly shifting the position of the radially outer portion of the rotor core 2 relative to the slits 22 radially outward. As a result, the slits 22 maintain contact between the rotor core 2 and the rotor shaft 1 even when centrifugal force is applied to the rotor core 2. Therefore, with the above configuration, the slits 22 can also be used as the core flow passages 23 while maintaining contact between the rotor core 2 and the rotor shaft 1.

[0081] As described above, this embodiment further includes a discharge member (end plate 3) including a discharge flow path 33 that discharges the coolant supplied from the supply flow path 5 on one axial side of the rotor core 2 from the other axial side, and the discharge flow path 33 includes an inclined surface 33a that is inclined toward the coil end portion 101c so that the discharged coolant is discharged toward the coil end portion 101c of the stator 101. This allows the inclined surface 33a to discharge the coolant toward the coil end portion 101c of the stator 101, so that not only the rotor 102 but also the coil end portion 101c of the stator 101 can be cooled.

[0082] The rotor 102 may also have the following configuration.

[0083] In this embodiment, as described above, the slits 22 have the inner slits 22a and the outer slits 22b that are provided radially outward of the inner slits 22a and positioned closer to the magnet holes 20 than the inner slits 22a, and the core flow passage 23 through which the coolant flows is formed by the outer slits 22b. This allows the coolant to flow through the outer slits 22b that are positioned closer to the magnet holes 20 and radially outward of the inner slits 22a, thereby effectively cooling the heat-generating permanent magnets 20a.

[0084] In this embodiment, as described above, the supply flow passages 5 provided in the set of end plates 3 and fixing members 4 on one axial side of the rotor core 2 are configured to supply the refrigerant to the rotor core 2 from one axial side of the rotor core 2 and cause the refrigerant to flow toward the other axial side of the rotor core 2, and the supply flow passages 5 provided in the set of end plates 3 and fixing members 4 on the other axial side of the rotor core 2 are configured to supply the refrigerant to the rotor core 2 from the other axial side of the rotor core 2 and cause the refrigerant to flow toward one axial side of the rotor core 2. This allows the refrigerant to flow in both axial directions, thereby enabling the rotor core 2 to be cooled in a balanced and even manner.

[0085] In this embodiment, as described above, the grooves 32 that form the boundary flow passages 52 include an annular groove 32a that extends annularly along the outer peripheral surface 1a of the rotor shaft 1, and a plurality of radial grooves 32b that extend radially outward from the annular groove 32a. This allows the annular groove 32a to easily disperse the refrigerant in the circumferential direction, and the radial grooves 32b to easily direct the refrigerant dispersed in the circumferential direction toward the radially outward direction. As a result, the rotor core 2 can be cooled uniformly and without unevenness in both the circumferential and radial directions.

[0086] In the present embodiment, as described above, the first connection flow passage 50 is connected to the annular groove portion 32a from the radially inner side, and the second connection flow passage 51 is connected to the radially outer end of the radial groove portion 32b from the rotor core 2 side. This allows the refrigerant to easily flow from the hollow portion 10 of the rotor shaft 1 to the annular groove portion 32a through the first connection flow passage 50, and allows the refrigerant to easily flow from the radial groove portion 32b to the core flow passage 23 of the rotor core 2 through the second connection flow passage 51.

[0087] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims rather than the description of the above embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0088] For example, in the above embodiment, the rotor core has slits and the refrigerant flows through the slits (the slits serve as core flow paths), but the present invention is not limited to this. In the present invention, the rotor core may not have slits, but may instead have a dedicated core flow path for the refrigerant to flow through.

[0089] In the above embodiment, an example has been shown in which end plates and fixing members are arranged on both axial sides of the rotor core, but the present invention is not limited to this. In the present invention, an end plate and fixing member may be arranged on only one axial side of the rotor core.

[0090] In the above embodiment, the axial movement restricting portion of the present invention is a fixing member that is crimped, but the present invention is not limited to this. In the present invention, the axial movement restricting portion may be configured as a flange provided on the rotor shaft. In this case, the flange contacts the end plate from the outside in the axial direction, thereby restricting axial movement of the end plate. The flange may be configured integrally with the rotor shaft or may be configured separately.

[0091] In the above embodiment, the refrigerant flows in both axial directions of the rotor core, but the present invention is not limited to this. In the present invention, the refrigerant may flow in only one axial direction of the rotor core.

[0092] In addition, in the above embodiment, an example was shown in which the slits include both an inner slit and an outer slit (double slits aligned in the radial direction), but the present invention is not limited to this. In the present invention, the slits may be a single slit aligned in the radial direction.

[0093] In the above embodiment, the grooves forming the boundary flow channels are provided only in the end plates, but the present invention is not limited to this. In the present invention, the grooves forming the boundary flow channels may be provided in both the end plates and the fixing member. Alternatively, the grooves forming the boundary flow channels may be provided only in the fixing member.

[0094] In the above embodiment, the grooves forming the boundary flow passage have an annular groove and radial grooves, but the present invention is not limited to this. For example, the grooves forming the boundary flow passage may have only radial grooves.

[0095] In the above embodiment, the fixing member is fixed to the rotor shaft by crimping, but the present invention is not limited to this. In the present invention, the fixing member may be fixed to the rotor shaft by press-fitting, tightening with a nut, or the like.

[0096] In addition, in the above embodiment, the number of core flow passages extending in the axial direction provided in the rotor core may be different from that in the above embodiment. [Explanation of symbols]

[0097] 1 rotor shaft 1a (rotor shaft) outer surface 2 rotor core 2a (rotor core) outer surface 2b One end face (axial direction of rotor core) 3 End plate (exhaust member) 4 Fixed member (axial movement restriction part) 4a (fixed member) outer surface 5 Supply Channel 10 (rotor shaft) hollow section 20 (rotor core) magnet hole 20a permanent magnet 21 Shaft insertion hole 22 Slit 23 Core channel 30 Inner end face (of end plate) 31 (end plate) outer end face 32 (End plate) groove 33 Discharge flow path 33a Inclined surface (of discharge flow path) 40 (Fixed member) end plate contact surface 50 (of the supply channel) first connecting channel 51 (of the supply channel) second connecting channel 52 Boundary channel (of supply channel) 101 Stator 101c (stator) coil end 102 rotor L1 Length (from the outer surface of the rotor shaft to the outer surface of the fixed member) L2 Length (from the outer surface of the rotor shaft to the outer surface of the rotor core)

Claims

1. a rotor shaft extending in an axial direction and having a hollow portion to which a refrigerant is supplied; a rotor core including a shaft insertion hole into which the rotor shaft is inserted and a core flow path extending in the axial direction through which a refrigerant flows; an end plate including an inner end surface in contact with one end surface of the rotor core in the axial direction and an outer end surface opposite the inner end surface in the axial direction; an axial movement restricting portion provided separately from the end plate, the axial movement restricting portion including an end plate contact surface that contacts the outer end surface of the end plate, and that restricts axial movement of the end plate and the rotor core relative to the rotor shaft by contacting the outer end surface; a supply flow path that supplies a coolant from the hollow portion to the core flow path, The supply flow path is a boundary flow path extending along a boundary between the outer end surface of the end plate and the end plate contact surface of the axial movement restricting portion; a first connecting flow passage provided in the rotor shaft and connecting the hollow portion and the boundary flow passage; a second connecting channel provided in the end plate and connecting the boundary channel and the core channel; The boundary flow passage is configured to connect the first connecting flow passage and the second connecting flow passage.

2. 2. The rotor according to claim 1, wherein a length from an outer peripheral surface of the rotor shaft to an outer peripheral surface of the axial movement restricting portion in a radial direction of the rotor core is shorter than half a length from the outer peripheral surface of the rotor shaft to the outer peripheral surface of the rotor core.

3. the end plate includes a groove portion recessed from the outer end surface toward the rotor core, The rotor according to claim 1 , wherein the boundary flow passage is formed by the groove and the end plate contact surface of the axial movement restricting portion.

4. the axial movement restricting portion is a fixed member that is fixed to the rotor shaft and thereby positioned in the axial direction, The rotor according to claim 1 , wherein the set of the end plate and the fixing member is provided on both one side and the other side of the rotor core in the axial direction.

5. The rotor core is a magnet hole in which a permanent magnet is disposed; a slit formed by a through hole provided radially inside the magnet hole and extending in the axial direction of the rotor core, The rotor according to claim 1 , wherein the core flow passage through which the coolant flows is formed by the slits.

6. a discharge member including a discharge flow path that discharges the refrigerant supplied from the supply flow path on one side of the rotor core in the axial direction from the other side of the rotor core in the axial direction, The rotor according to claim 1 , wherein the discharge flow passage includes an inclined surface that is inclined toward the coil end portion of the stator so that the discharged coolant is discharged toward the coil end portion of the stator.

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