Rotary electric machine and vehicle driving device with the same

Abstract

To cool a stator coil and magnets of a rotor according to the rotating speed of the rotor.SOLUTION: A rotary electric machine comprises a rotor 110 and a stator 140 arranged on an outer-diameter side of the rotor 110. A rotor shaft 111 is provided on an inner peripheral side of the rotor 110, and a shaft flow passage 120 is provided inside the rotor shaft 111. The rotor 110 has: a first flow passage 131a which extends outwards in a radial direction of the rotor shaft 111, and has a first discharge port made open radially outwards; and a second flow passage which extends radially outward after extending outward in a radial direction of the rotor shaft 111 to extend axially inside a rotor core 112, and has a second discharge port made open radially outwards. The first flow passage 131a and the second flow passage are connected to the shaft flow passage 120, and the second discharge port is arranged radially outside the first discharge port.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a rotating electric machine and a vehicle drive device including the same. [Background technology]

[0002] Techniques for cooling rotating electric machines include those described in Patent Documents 1 to 3, for example. In Patent Document 1, an oil hole is provided in the center of a shaft, and a supply hole extending toward the outer periphery of the shaft is inserted into the oil hole. A rotor mounted on the shaft is provided with a cooling oil passage extending axially through the shaft, and a receiver at the end of the cooling oil passage covers the opening of the cooling oil passage. When the rotor rotates, the receiver receives lubricating oil discharged from the supply hole, which is open to the atmosphere. The lubricating oil is then circulated through the cooling oil passage to cool the rotor, and the lubricating oil is then discharged from the cooling oil passage to cool the stator coil ends.

[0003] In Patent Document 2, an oil passage is formed axially through a rotor core. One end of the rotor core is provided with an end plate having an oil supply hole communicating with the oil passage and an oil discharge hole through which oil is ejected into the coil. The cross-sectional area of ​​the oil passage is larger downstream than upstream in the oil flow. The other end of the rotor core is provided with an end plate having an oil discharge hole communicating with the oil passage with an enlarged cross-sectional area. The coil is cooled by oil discharged from the oil discharge hole, and the rotor is cooled by oil flowing through the oil passage.

[0004] In Patent Document 3, a hole is formed in the rotating shaft, penetrating radially outward from the rotating shaft and communicating with the shaft flow path. An end plate is provided at the axial end of the rotating core, and a groove is formed in this end plate, forming a refrigerant passage between the wall surface of the end plate and the end face of the rotating core. This refrigerant passage communicates with the hole in the shaft. A first discharge hole is provided midway through the refrigerant passage, and a second discharge hole is provided at the end of the refrigerant passage. Oil that has flowed through the shaft flow path, the hole, and the refrigerant passage is discharged from the first discharge hole and the second discharge hole to cool the coil end. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2019-68622 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-223075 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-142788 Summary of the Invention [Problem to be solved by the invention]

[0006] For example, in a rotating electrical machine used to drive a vehicle, when the rotor speed is low and a large torque is required, the current flowing through the stator coil increases, causing the stator coil to generate heat, and therefore the stator coil must be cooled.On the other hand, when the rotor speed is high, the eddy current loss in the rotor increases, causing heat generation, and therefore the rotor in which the magnets are arranged must be cooled.

[0007] In the technology described in Patent Document 1, the rotor rotates, and the lubricating oil discharged from the supply holes by centrifugal force is received in a receiver, and the lubricating oil is then circulated through cooling oil passages to cool the rotor, and the lubricating oil is then discharged from the cooling oil passages to cool the stator coil ends.However, because the lubricating oil discharged from the supply holes is released to the atmosphere, it is not possible to increase the flow rate of the lubricating oil flowing through the cooling oil passages using centrifugal force, even if the rotor rotation speed increases.As a result, the technology described in Patent Document 1 has the problem of not being able to sufficiently cool the magnets arranged in the rotor as the rotor rotation speed increases.

[0008] In the technology described in Patent Document 2, the cross-sectional area of ​​the oil passage is larger downstream than upstream in the oil flow, so even if the oil passage is open to the atmosphere and the rotor rotation speed increases, the flow rate of oil flowing through the oil passage cannot be increased by utilizing centrifugal force. As a result, the technology described in Patent Document 2 has the problem that the magnets arranged in the rotor cannot be sufficiently cooled in response to an increase in the rotor rotation speed.

[0009] In the technology described in Patent Document 3, a flow path for the coolant to flow in the axial direction of the rotating core is not formed, making it difficult to cool the magnets arranged in the rotor.

[0010] An object of the present invention is to provide a rotating electric machine capable of cooling the stator coil and the magnet of the rotor in accordance with the rotation speed of the rotor, and a vehicle drive device including the same. [Means for solving the problem]

[0011] In order to achieve the above object, the present invention provides a rotating electric machine comprising a rotor having a magnet arranged within a rotor core, and a stator arranged on the outer diameter side of the rotor, wherein a rotor shaft is provided on the inner circumference side of the rotor, and a shaft flow path through which a refrigerant flows is provided inside the rotor shaft, and the rotor has a first flow path extending radially outward from the rotor shaft and having a first discharge port opening radially outward, and a second flow path extending radially outward from the rotor shaft, extending axially inside the rotor core, and then extending radially outward and having a second discharge port opening radially outward, wherein the first flow path and the second flow path are connected to the shaft flow path, and the second discharge port is arranged radially outward of the first discharge port. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a rotating electric machine capable of cooling the stator coil and the magnet of the rotor in accordance with the rotation speed of the rotor, and a vehicle drive device including the same. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic configuration diagram of an electric vehicle according to an embodiment of the present invention; [Figure 2] 1 is a schematic configuration diagram of a system for cooling a vehicle drive device according to an embodiment of the present invention; [Figure 3] FIG. 2 is an exploded perspective view of the rotor 110 as seen from the anti-load side. [Figure 4] FIG. 2 is an exploded perspective view of the rotor 110 as seen from the load side. [Figure 5A] FIG. 2 is a plan view of the first end plate and the third end plate as viewed from the side facing the second end plate and the fourth end plate. [Figure 5B] FIG. 3 is a plan view of the first end plate and the third end plate as viewed from the side facing the rotor core. [Figure 6] 2 is a cross-sectional view of the rotor taken in a direction perpendicular to the axial direction. FIG. [Figure 7]1 is a cross-sectional perspective view of a rotor 110 according to a first embodiment of the present invention, cut along the axial direction. [Figure 8] 1 is a cross-sectional view of the upper half of a rotor 110 taken along the axial direction. [Figure 9] FIG. 10 is a diagram showing the relationship between the flow rates in the first flow path and the second flow path in response to changes in the rotation speed. [Figure 10] FIG. 6 is a cross-sectional view of a rotor according to a second embodiment of the present invention, taken in a direction perpendicular to the axial direction. [Figure 11] FIG. 10 is a cross-sectional view of the upper half of a rotor 110 according to a third embodiment of the present invention, taken along the axial direction. [Figure 12] FIG. 10 is a cross-sectional perspective view of a rotor 110 according to a fourth embodiment of the present invention, cut along the axial direction. [Figure 13] FIG. 10 is a cross-sectional perspective view of a rotor 110 according to a fifth embodiment of the present invention, cut along the axial direction. [Figure 14] FIG. 10 is a cross-sectional perspective view of a rotor 110 according to a sixth embodiment of the present invention, cut along the axial direction. DETAILED DESCRIPTION OF THE INVENTION

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Like elements are designated by like reference numerals and similar descriptions will not be repeated.

[0015] The various components of the present invention do not necessarily have to be independent entities, and it is acceptable for one component to be made up of multiple members, for multiple components to be made up of one member, for one component to be part of another component, or for part of one component to overlap with part of another component. [Example]

[0016] Fig. 1 is a schematic configuration diagram of an electric vehicle according to a first embodiment of the present invention. In Fig. 1, a vehicle body 1 is equipped with a vehicle drive device 3 for driving wheels 2. The vehicle drive device 3 is a drive unit that integrates devices such as a rotating electric machine and an inverter.

[0017] An oil cooler 4 is connected to the vehicle drive system 3 via a pipe 7. The pipe 7 is equipped with a refrigerant pump 8 that pumps a first refrigerant, causing the refrigerant to flow through the devices in the vehicle drive system 3 and cool these devices. A chiller 6 is also connected to the oil cooler 4 via a pipe 5, and a second refrigerant flows through the oil cooler 4, the pipe 5, and the chiller 6. Heat exchange occurs in the oil cooler 4, and the heated first refrigerant is cooled by the second refrigerant. The second refrigerant is pumped by a pump 9 equipped in the pipe 5 and sent to the chiller 6. In the chiller 6, the heated second refrigerant is cooled by the wind generated when the vehicle is traveling. The cooled refrigerant is sent back to the oil cooler 4.

[0018] FIG. 2 is a schematic configuration diagram of a system for cooling a vehicle drive device according to the first embodiment of the present invention.

[0019] As shown by the arrows in the figure, the side to which the vehicle drive device 3 transmits drive force is defined as the "load side," the opposite side as the "anti-load side," the upward direction as the "upper-upper side," and the downward direction as the "lower-lower side." Additionally, the direction along the shaft is defined as the "axial direction," the circumference of the rotor shaft as the "circumferential direction," the radial direction (radial direction) when the shaft is the center as the "radial direction," and the direction perpendicular to the horizontal line as the vertical direction.

[0020] The vehicle drive device 3 includes a rotating electric machine 100, a reducer 200 that transmits the driving force of the rotating electric machine 100, and an inverter (not shown).

[0021] The rotating electric machine 100 includes a rotor 110 and a stator 140 disposed on the outer diameter side of the rotor 110. The rotor 110 and the stator 140 are housed in a housing 101.

[0022] The rotor 110 is provided on its inner peripheral side with a rotor shaft 111 rotatably supported by bearings 150, 151, and 152. The load side of the rotor shaft 111 is provided with a drive gear 201 constituting a reducer 200, a driven gear 202 that meshes with the drive gear 201 and transmits driving force to the drive gear 201, a driven gear shaft 203 provided on the driven gear 202, and bearings 204 and 205 that support the driven gear shaft 203.

[0023] The stator 140 includes a plurality of starter coils 141 inserted into slots formed in the stator core.

[0024] The rotor shaft 111 is hollow, and has a shaft flow path 120 through which a refrigerant flows. The refrigerant flowing through the shaft flow path cools the stator coil 141 and the rotor 110, and then falls into an oil pan 154 located below the rotating electrical machine 100. The refrigerant that falls and is collected in the oil pan 154 is pumped by the refrigerant pump 8 and sent to the oil cooler 4 and the shaft flow path 120. Then, after cooling the stator coil 141 and the rotor 110, the refrigerant falls back into the oil pan 154. In this embodiment, the refrigerant is circulated in this manner to cool the stator coil 141 and the rotor 110.

[0025] Next, a detailed structure for cooling the stator coil 141 and the rotor 110 will be described.

[0026] Fig. 3 is an exploded perspective view of the rotor 110 as viewed from the anti-load side. Fig. 4 is an exploded perspective view of the rotor 110 as viewed from the load side. Fig. 5A is a plan view of the first end plate and the third end plate as viewed from the side facing the second end plate and the fourth end plate. Fig. 5B is a plan view of the first end plate and the third end plate as viewed from the side facing the rotor core. Fig. 6 is a cross-sectional view of the rotor cut in a direction perpendicular to the axial direction.

[0027] The rotor 110 includes a rotor core 112 formed by stacking a plurality of steel plates, a first end plate 113 arranged at one axial end (anti-load side) of the rotor core 112, a second end plate 114 arranged at one axial outer side (anti-load side) of the first end plate 113, a third end plate 115 arranged at the other axial end (load side) of the rotor core 112, and a fourth end plate 116 arranged at the other axial outer side (load side) of the third end plate 115. The first end plate 113 is arranged so as to be sandwiched between the second end plate 114 and the rotor core 112, and the third end plate 115 is arranged so as to be sandwiched between the fourth end plate 116 and the rotor core 112.

[0028] The outer surface of the rotor shaft 111 is provided with a first shaft flow path hole 121 communicating with the shaft flow path 120, a second shaft flow path hole 122 communicating with the shaft flow path 120 and positioned adjacent to the first shaft flow path hole 121, a third shaft flow path hole 123 communicating with the shaft flow path 120, and a fourth shaft flow path hole 124 communicating with the shaft flow path 120 and positioned adjacent to the third shaft flow path hole 123.

[0029] The first shaft flow passage hole 121 and the second shaft flow passage hole 122 are arranged at the same position in the circumferential direction of the rotor shaft 111, and the third shaft flow passage hole 123 and the fourth shaft flow passage hole 124 are arranged at the same position in the circumferential direction of the rotor shaft 111. The first shaft flow passage hole 121 (second shaft flow passage hole 122) and the third shaft flow passage hole 123 (fourth shaft flow passage hole 124) are arranged to be offset in the circumferential direction of the rotor shaft 111. Furthermore, a plurality of the first shaft flow passage holes 121 to the fourth shaft flow passage holes 124 are provided in the circumferential direction of the rotor shaft 111.

[0030] An insertion hole 113a is formed in the center of the first end plate 113, penetrating in the axial direction and into which the rotor shaft 111 is inserted.

[0031] A plurality of first grooves 131 are formed on the outer surface (on the second end plate 114 side) of the first end plate 113, extending radially outward from the insertion hole 113a.

[0032] A plurality of second grooves 132 are formed on the inner surface (rotor core 112 side) of the first end plate 113, extending radially outward from the insertion hole 113a.

[0033] Furthermore, a plurality of protruding portions 113b protruding radially outward are formed on the first end plate 113. A plurality of sixth grooves 136 extending radially outward are formed on the surface of the protruding portion 113b on the inner side (rotor core 112 side) of the first end plate 113.

[0034] The first end plate 113 is disposed at a position overlapping the first shaft passage hole 121 and the second shaft passage hole 122 formed in the rotor shaft 111. The first groove portion 131 communicates with the first shaft passage hole 121, and the second groove portion 132 communicates with the second shaft passage hole 122.

[0035] When the first end plate 113 comes into contact with the second end plate 114, the first groove 131 is covered, and a first flow path 131a through which the refrigerant flows is formed. That is, the first groove 131 is formed by being sandwiched between the first end plate 113 and the second end plate 114. The first flow path 131a is formed so as to penetrate radially from the insertion hole 113a to the radially outer side.

[0036] When the first end plate 113 comes into contact with the rotor core 112, the second groove 132 is covered, and a second anti-load side flow path 132a (second flow path) through which the refrigerant flows is formed. Furthermore, when the first end plate 113 comes into contact with the rotor core 112, the sixth groove 136 is covered, and a fourth anti-load side flow path 136a (fourth flow path) through which the refrigerant flows is formed. That is, the second anti-load side flow path 132a, which is a part of the second flow path, and the fourth anti-load side flow path 136a, which is a part of the fourth flow path, are sandwiched between the first end plate 113 and the rotor core 112 and formed.

[0037] The anti-load side second flow passage 132a (second flow passage) has a radially inner side that penetrates the insertion hole 113a, but a radially outer side that is blocked by a blocking portion 132s (FIG. 5B). A radially outer end 132e of the anti-load side second flow passage 132a (second flow passage) is connected to the rotor core flow passage 130. The anti-load side fourth flow passage 136a (fourth flow passage) has a radially outer side that penetrates, but a radially inner side that is blocked. A radially inner end 136e of the anti-load side fourth flow passage 136a (fourth flow passage) is connected to the rotor core flow passage 130.

[0038] The second end plate 114 is formed with an insertion hole 114a into which the rotor shaft 111 is inserted, a notch 114b which serves as the first outlet of the first flow path 131a, and a fitting notch 114c into which the protrusion 113b fits and which serves as the fourth outlet.

[0039] In this embodiment, by combining the first end plate 113, the second end plate 114, and the rotor core 112, a first flow path 131a, a second anti-load side flow path 132a (second flow path), and a fourth anti-load side flow path 136a (fourth flow path) are formed, and by combining these with the rotor shaft 111, the first flow path 131a and the first shaft flow path hole 121 are connected, and the second anti-load side flow path 132a (second flow path) and the second shaft flow path hole 122 are connected.

[0040] An insertion hole 115a is formed in the center of the third end plate 115, penetrating in the axial direction and into which the rotor shaft 111 is inserted.

[0041] A plurality of third grooves 133 are formed on the outer surface (fourth end plate 116 side) of the third end plate 115, extending radially outward from the insertion hole 115a.

[0042] A plurality of fourth grooves 134 are formed on the inner surface (on the rotor core 112 side) of the third end plate 115, extending radially outward from the insertion hole 115a.

[0043] Furthermore, a plurality of protruding portions 115b protruding radially outward are formed on the third end plate 115. A plurality of fifth grooves 135 extending radially outward are formed on the surface of the protruding portion 115b on the inner side (rotor core 112 side) of the third end plate 115.

[0044] The third end plate 115 is disposed at a position overlapping the third shaft passage hole 123 and the fourth shaft passage hole 124 formed in the rotor shaft 111. The third groove portion 133 communicates with the third shaft passage hole 123, and the fourth groove portion 134 communicates with the fourth shaft passage hole 124.

[0045] When the third end plate 115 comes into contact with the fourth end plate 116, the third groove 133 is covered, and a third flow path 133a through which the refrigerant flows is formed. That is, the third groove 133 is formed by being sandwiched between the third end plate 115 and the fourth end plate 116. The third flow path 133a is formed so as to penetrate radially from the insertion hole 113a to the radially outer side.

[0046] When the third end plate 115 comes into contact with the rotor core 112, the fourth groove 134 is covered, and a fourth load-side flow path 134a (fourth flow path) through which the refrigerant flows is formed. When the third end plate 115 comes into contact with the rotor core 112, the fifth groove 135 is covered, and a second load-side flow path 135a (second flow path) through which the refrigerant flows is formed. That is, the fourth load-side flow path 134a, which is a part of the fourth flow path, and the second load-side flow path 135a, which is a part of the second flow path, are formed by being sandwiched between the third end plate 115 and the rotor core 112.

[0047] The load-side fourth flow passage 134a (fourth flow passage) has a radially inner side that penetrates the insertion hole 115a, but a radially outer side that is blocked by a blocking portion 134s (FIG. 5B). A radially outer end 134e of the load-side fourth flow passage 134a (second flow passage) is connected to the rotor core flow passage 130. The load-side second flow passage 135a (second flow passage) has a radially outer side that penetrates, but a radially inner side that is blocked. A radially inner end 135e of the load-side second flow passage 135a (second flow passage) is connected to the rotor core flow passage 130.

[0048] The fourth end plate 116 is formed with an insertion hole 116a into which the rotor shaft 111 is inserted, a notch 116b which serves as the third outlet of the third flow path 133a, and a fitting notch 116c into which the protrusion 115b fits and which serves as the second outlet.

[0049] In this embodiment, by combining the third end plate 115, the fourth end plate 116, and the rotor core 112, the third flow path 133a and the load side fourth flow path 134a (fourth flow path) are formed, and by combining these with the rotor shaft 111, the third flow path 133a and the third shaft flow path hole 123 are connected, and the load side fourth flow path 134a (fourth flow path) and the fourth shaft flow path hole 124 are connected.

[0050] In addition, in this embodiment, the connection points of the first flow path and the second flow path with the shaft flow path 120 are on one side of the rotor shaft 111, and the connection points of the third flow path and the fourth flow path with the shaft flow path 120 are on the other side of the rotor shaft 111.

[0051] Next, rotor core 112 will be described with reference to Figures 3 to 6. A plurality of permanent magnets 117 (magnets) are arranged in rotor core 112. The permanent magnets 117 are arranged with north and south poles alternately in the circumferential direction. Furthermore, the permanent magnets 117 arranged at one pole are divided.

[0052] The rotor core 112 is formed with an insertion hole 112a that penetrates in the axial direction and into which the rotor shaft 111 is inserted, and multiple rotor core flow paths 130 (rotor core flow paths 130a-130h) that penetrate in the axial direction and constitute part of the second flow path and the fourth flow path through which the refrigerant flows. The multiple rotor core flow paths 130a-130h are arranged so as to maintain magnetic pole symmetry or magnetic pole pair symmetry. In this embodiment, the multiple rotor core flow paths 130a-130h are arranged at 45° intervals in the circumferential direction. According to this embodiment, the multiple rotor core flow paths 130a-130h that constitute the second flow path and the fourth flow path are arranged so as to maintain magnetic pole symmetry or magnetic pole pair symmetry, which makes it possible to suppress differences in motor characteristics between power running and regeneration.

[0053] Of the multiple rotor core flow paths 130, the rotor core flow paths 130a to 130d each communicate with a counter-load side second flow path 132a (second flow path) at a radially outer end 132e formed in the first end plate 113, and the rotor core flow paths 130e to 130h each communicate with a counter-load side fourth flow path 136a (fourth flow path) at a radially inner end 136e formed in the first end plate 113. That is, the rotor core flow paths 130a to 130d serve as second flow paths, and the rotor core flow paths 130e to 130h serve as fourth flow paths. Furthermore, of the multiple rotor core flow paths 130, the rotor core flow paths 130a to 130d each communicate with a load side second flow path 135a (second flow path) at the radial inner end portion 135e formed on the third end plate 115, and the rotor core flow paths 130e to 130h each communicate with a load side fourth flow path 134a (fourth flow path) at the radial outer end portion 134e formed on the third end plate 115.

[0054] The second flow path in this embodiment extends radially outward from the rotor shaft 111 via the anti-load side second flow path 132a and connects to the rotor core flow paths 130a to 130d, extends axially inside the rotor core 112 via the rotor core flow paths 130a to 130d, and then connects to the load side second flow path 135a, extends radially outward, and has a second discharge port that opens radially outward.

[0055] Similarly, the fourth flow path in this embodiment extends radially outward from the rotor shaft 111 via the load side fourth flow path 134a and connects to the rotor core flow paths 130e to 130h, extends axially inside the rotor core 112 via the rotor core flow paths 130e to 130h, and then connects to the anti-load side fourth flow path 136a, extends radially outward, and has a fourth discharge port that opens radially outward.

[0056] Next, a description will be given of the flow of refrigerant in the rotor 110. Fig. 7 is a cross-sectional perspective view of the rotor 110 according to the first embodiment of the present invention, cut along the axial direction. Fig. 8 is a cross-sectional view of the upper half of the rotor 110, cut along the axial direction.

[0057] The rotor shaft 111 has an open end (anti-load side) in the axial direction and a solid end (load side). A refrigerant pump 8 is connected to the opening at one end of the rotor shaft 111 via an oil cooler 4 (FIG. 2). When the rotor 110 rotates, some of the refrigerant that has flowed into the shaft flow path 120 is discharged from the first shaft flow path hole 121 and the second shaft flow path hole 122.

[0058] The refrigerant discharged radially outward from the first shaft flow path hole 121 passes through the first flow path 131a and is discharged from the notched portion 114b (first discharge port). The refrigerant discharged from the notched portion 114b hits the stator coil 141 and cools it.

[0059] The refrigerant discharged radially outward from the second shaft flow passage hole 122 passes through the counter-load side second flow passage 132a, the rotor core flow passages 130 (130a, 130c, 130e, 130g), and the load side second flow passage 135a, which form the second flow passage, and is then discharged from the fitting notch 116c (second discharge port). The refrigerant discharged from the fitting notch 116c hits the stator coil 141 and cools it. The refrigerant flowing through the second flow passage also flows inside the rotor core 112, thereby cooling the permanent magnets 117 arranged in the rotor core 112.

[0060] Similarly, the refrigerant discharged radially outward from the third shaft flow path hole 123 passes through the third flow path 133a and is discharged from the notched portion 116b (third discharge port). The refrigerant discharged from the notched portion 116b hits the stator coil 141 and cools it.

[0061] The refrigerant discharged radially outward from the fourth shaft flow passage hole 124 passes through the load-side fourth flow passage 134a, the rotor core flow passages 130 (130b, 130d, 130f, 130h), and the non-load-side fourth flow passage 136a, which form the fourth flow passage, and is then discharged from the fitting notch 114c (fourth discharge port). The refrigerant discharged from the fitting notch 114c hits the stator coil 141 and cools it. In addition, the refrigerant flowing through the fourth flow passage flows inside the rotor core 112, thereby cooling the permanent magnets 117 arranged in the rotor core 112.

[0062] The rotor core flow paths 130a to 130d forming the second flow path and the rotor core flow paths 130e to 130h forming the fourth flow path are arranged so that the axial flows thereof are opposite to each other and alternate in the circumferential direction.

[0063] The first flow passages, the second flow passages, the third flow passages, and the fourth flow passages are each arranged in plurals (four of each) at equal intervals in the circumferential direction. The number of first flow passages and second flow passages is the same on one side in the axial direction, and the number of third flow passages and fourth flow passages is the same on the other side in the axial direction.

[0064] Furthermore, in this embodiment, the first and third flow paths are arranged so as not to overlap when viewed from the axial direction, and are offset by 45° in the circumferential direction. Similarly, the second and fourth flow paths are arranged so as not to overlap when viewed from the axial direction, and are offset by 45° in the circumferential direction. By arranging them in this manner, the weight balance of the rotor in the circumferential direction can be made uniform, and eccentricity during rotor rotation can be suppressed.

[0065] Rotating electric machines used to drive vehicles and the like change their rotation speed depending on the load. At low rotation speeds, a large motor torque is required, so the current flowing through the stator coil increases, and the amount of heat generated by the stator coil increases. On the other hand, at high rotation speeds, eddy current loss increases, causing the temperature of the permanent magnet to rise. In other words, it is preferable for rotating electric machines to mainly cool the stator coil at low rotation speeds and mainly cool the permanent magnet at high rotation speeds.

[0066] In this embodiment, the fitting notch 116c (second outlet) that serves as the outlet of the second flow path is disposed radially outward of the notch 114b (first outlet) that serves as the outlet of the first flow path. That is, the outlet position γ02 of the fitting notch 116c (second outlet) is greater than the outlet position γ01 of the notch 114b (first outlet) (γ02>γ01).

[0067] In this embodiment, the fitting notch 116c (second discharge port) is disposed radially outward of the notch 114b (first discharge port), so the flow path resistance of the second flow path is greater than that of the first flow path. When the rotor 110 is rotated, the flow path is filled with refrigerant, and the refrigerant is discharged from the notch 114b (first discharge port) and the fitting notch 116c (second discharge port). However, when the rotation speed of the rotor 110 is low (low rotation speed), the centrifugal force caused by the rotation of the rotor 110 is small, so the amount of refrigerant discharged from the notch 114b (first discharge port), which has small flow path resistance, increases.

[0068] On the other hand, when the rotation speed of the rotor 110 is high (high-speed rotation), the centrifugal force acting on the refrigerant at the mating notch 116c (second discharge port), which is located radially outward from the notch 114b (first discharge port), becomes larger, and therefore the amount of refrigerant flowing through the second flow paths (anti-load side second flow path 132a, rotor core flow paths 130a-130e, load side second flow path 135a) increases compared to the amount of refrigerant flowing through the first flow path.

[0069] FIG. 9 is a diagram showing the relationship between the flow rates of the first and second flow paths depending on the rotation speed. In FIG. 9, the total discharge rate is the sum of the discharge rate of the first and second flow paths. As shown in FIG. 9, as the rotation speed increases, the discharge rate from the first flow path decreases. On the other hand, as the rotation speed increases, the discharge rate from the second flow path increases. In this way, in this embodiment, the discharge rates from the first and second flow paths change depending on the rotation speed.

[0070] According to this embodiment, when the rotor rotation speed is low, the amount of refrigerant flowing through the first flow path is increased to mainly cool the stator coil, which generates a large amount of heat, and when the rotor rotation speed is high, the amount of refrigerant flowing through the second flow path is increased to mainly cool the permanent magnet, whose temperature rises due to increased eddy current loss.

[0071] Furthermore, according to this embodiment, the first flow path and the second flow path are each independently connected to the shaft flow path 120, so that the centrifugal pump effect due to the centrifugal force acting on the refrigerant in the second flow path acts only on the second flow path, thereby further improving the increase in the flow rate of the second flow path due to the centrifugal pump effect during high-speed rotation.

[0072] Although not explained further, the relationship between the notch portion (third outlet) 116b and the mating notch portion (fourth outlet) 114c is the same as the relationship between the notch portion 114b (first outlet) and the mating notch portion 116c (second outlet). [Example]

[0073] Second Embodiment A second embodiment of the present invention will be described with reference to Fig. 10. Components common to the first embodiment will be given the same reference numerals, and detailed descriptions thereof will be omitted. Fig. 10 is a cross-sectional view of a rotor according to the second embodiment of the present invention, cut in a direction perpendicular to the axial direction.

[0074] In the first embodiment, the multiple rotor core passages 130a to 130h are arranged so as to maintain magnetic pole symmetry or magnetic pole pair symmetry, whereas in the second embodiment, the multiple rotor core passages 130a to 130h are arranged so as not to maintain magnetic pole symmetry or magnetic pole pair symmetry.

[0075] According to this embodiment, by arranging the rotor core flow paths 130a to 130d constituting the second flow path and the rotor core flow paths 130e to 130h constituting the fourth flow path so as not to maintain magnetic pole symmetry or magnetic pole pair symmetry, the amplitude of the circular vibration mode corresponding to the symmetry of the rotor shape can be reduced, and vibration and noise can be suppressed. [Example]

[0076] Third Embodiment A third embodiment of the present invention will be described with reference to Fig. 11. Components common to the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted. Fig. 11 is a cross-sectional view of the upper half of a rotor 110 according to the third embodiment of the present invention, taken along the axial direction.

[0077] In Example 1, the first flow path and the anti-load side second flow path 132a (second flow path) were each independent and connected to the shaft flow path 120, but in Example 3, the first flow path and the anti-load side second flow path 132a (second flow path) share a connection portion to the shaft flow path 120.

[0078] The outer peripheral surface of the rotor shaft 111 is provided with a second shaft passage hole 122 communicating with the shaft passage 120, and a fourth shaft passage hole 124 communicating with the shaft passage 120. A counter-load side second passage 132a (second passage) and the second shaft passage hole 122 communicate with each other.

[0079] One end of a branched flow path 137 is connected to the anti-load side second flow path 132a (second flow path), and the other end of the branched flow path 137 is connected to the first flow path 131a.

[0080] The refrigerant discharged from the second shaft flow path hole 122 flows through the counter-load side second flow path 132a (second flow path), and is branched at the branch flow path 137 to flow into the first flow path 131a and then flow through the first flow path 131a. The subsequent flow of the refrigerant is the same as in the first embodiment, and therefore a description thereof will be omitted.

[0081] According to this embodiment, the first flow path and the second flow path share a common communicating portion with the shaft flow path, so that the flow path structure can be simplified.

[0082] Although the explanation is omitted, the third flow path and the fourth flow path are connected to the shaft flow path in the same manner, and share a communicating portion with the shaft flow path. [Example]

[0083] A fourth embodiment of the present invention will be described with reference to Fig. 12. Components common to the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted. Fig. 12 is a cross-sectional perspective view of a rotor 110 according to the fourth embodiment of the present invention, cut along the axial direction.

[0084] In the fourth embodiment, the cross-sectional areas of the counter-load side second flow passage 132a and the load side second flow passage 135a, which form the second flow passage, are made different from each other. The cross-sectional area of ​​the counter-load side second flow passage 132a located upstream of the second flow passage (upstream side cross-sectional area S u ) is the flow path cross-sectional area of ​​the load side second flow path 135a located on the downstream side (downstream flow path cross-sectional area S d ) or more.

[0085] According to this embodiment, by making the cross-sectional area of ​​the flow path smaller on the downstream side than on the upstream side, it is possible to suppress a reduction in the pressure difference created by the centrifugal force acting on the refrigerant when atmospheric air enters the inside of the flow path from the discharge port, thereby further improving the effect of increasing the flow rate of the second flow path during high-speed rotation.

[0086] In this embodiment, the second flow path has been described, but the first flow path, the third flow path, and the fourth flow path may also be configured in the same manner. [Example]

[0087] A fifth embodiment of the present invention will be described with reference to Fig. 13. Components common to the first embodiment will be given the same reference numerals, and detailed descriptions thereof will be omitted. Fig. 13 is a cross-sectional perspective view of a rotor 110 according to the fifth embodiment of the present invention, cut along the axial direction.

[0088] In the fifth embodiment, the first flow path 131a and the anti-load side second flow path 132a forming the second flow path have different flow path cross-sectional areas. The flow path cross-sectional area S1 of the first flow path 131a is set to be equal to or larger than the flow path cross-sectional area S2 of the anti-load side second flow path 132a located upstream of the second flow path.

[0089] According to this embodiment, by making the flow path cross-sectional area of ​​the first flow path equal to or greater than the flow path cross-sectional area of ​​the second flow path, the flow path resistance of the first flow path can be reduced and the flow rate ratio of the first flow path during low-speed rotation can be increased, thereby improving the cooling performance of the stator coil during low-speed rotation. [Example]

[0090] Sixth embodiment of the present invention will be described with reference to Fig. 14. Components common to those of the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted. Fig. 14 is a cross-sectional perspective view of a rotor 110 according to the sixth embodiment of the present invention, cut along the axial direction.

[0091] In the sixth embodiment, the cross-sectional areas of the first shaft passage hole 121 and the second shaft passage hole 122 are different from each other. i1 is the cross-sectional area S of the second shaft passage hole 122 i2 The following is stated.

[0092] According to this embodiment, by making the inlet cross-sectional area of ​​the first flow path smaller than the inlet cross-sectional area of ​​the second flow path, the inlet pressure loss, which is the main pressure loss during high-speed rotation, can be made smaller in the second flow path than in the first flow path, and therefore the flow rate ratio of the second flow path during high-speed rotation can be increased.

[0093] It should be noted that the present invention is not limited to the above-described embodiment, but includes various modifications. The above-described embodiment has been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to an embodiment having all of the described configurations. [Explanation of symbols]

[0094] 1... vehicle body, 2... wheel, 3... vehicle drive device, 4... oil cooler, 5... piping, 6... chiller, 7... piping, 8... refrigerant pump, 100... rotating electric machine, 101... housing, 110... rotor, 111... rotor shaft, 112... rotor core, 113... first end plate, 113a... insertion hole, 114... second end plate, 114a... insertion hole, 114b... notch portion (first discharge port), 114c... mating notch portion (fourth discharge port), 115... third end plate, 115a... insertion hole, 115b... protrusion, 116... fourth end plate, 116a... insertion hole, 116b... notch portion (third discharge port), 116c... mating notch portion (second discharge port) outlet), 117... permanent magnet, 120... shaft flow passage, 121... first shaft flow passage hole, 122... second shaft flow passage hole, 123... third shaft flow passage hole, 124... fourth shaft flow passage hole, 130, 130a to 130h... rotor core flow passage, 131... first groove portion, 131a... first flow passage, 132... second groove portion, 132a... anti-load side second flow passage (second flow passage), 132s... damming portion, 132e... radially outer end portion, 133... third groove portion, 133a... third flow passage, 134... fourth groove portion, 134a... load side fourth flow passage (fourth flow passage), 134s... damming portion, 134e... radially outer end portion, 135... fifth groove portion 135a...load side second flow path (second flow path), 135e...radially inner end portion, 136...sixth groove portion, 136a...anti-load side fourth flow path (fourth flow path), 136e...radially inner end portion, 137...branch flow path, 140...stator, 141...starter coil, 150, 151, 152...bearings, 154...oil pan, 200...reduction gear, 201...drive gear, 202...driven gear, 203...driven gear shaft, 204, 205...bearings

Claims

1. A rotating electric machine including a rotor having a magnet disposed within a rotor core, and a stator disposed on an outer diameter side of the rotor, a rotor shaft is provided on the inner circumferential side of the rotor, and a shaft flow passage through which a refrigerant flows is provided inside the rotor shaft; The rotor is a first flow passage extending inside the rotor radially outward of the rotor shaft and having a first outlet port opening radially outward; a second flow path extending radially outwardly of the rotor shaft through an interior of the rotor and axially through an interior of the rotor core, and then extending radially outwardly through the interior of the rotor and having a second discharge port that opens radially outwardly; The first flow passage and the second flow passage are in communication with the shaft flow passage, The rotating electric machine according to claim 1, wherein the second discharge port is disposed radially outward of the first discharge port.

2. In claim 1, a plurality of the first flow passages and a plurality of the second flow passages are provided at equal intervals in a circumferential direction,

3. In claim 1, A rotating electric machine, comprising: a first flow passage and a second flow passage, the number of which is equal to one another.

4. In claim 1, The rotor is a third flow passage extending radially outward of the rotor shaft and having a third outlet port opening radially outward; a fourth flow passage extending in the axial direction inside the rotor core and then extending radially outward and having a fourth discharge port opening toward the radially outward direction, the third flow passage and the fourth flow passage are connected to the shaft flow passage; The fourth discharge port is provided radially outward of the third discharge port, a connection portion of the first flow path and the second flow path with the shaft flow path is located on one side of the rotor shaft, and a connection portion of the third flow path and the fourth flow path with the shaft flow path is located on the other side of the rotor shaft.

5. In claim 4, a flow direction in the axial direction of the second flow passage and a flow direction in the axial direction of the fourth flow passage opposed to each other.

6. In claim 1, A rotating electric machine, characterized in that the second flow passages are arranged so as to maintain magnetic pole symmetry or magnetic pole pair symmetry.

7. In claim 1, A rotating electric machine, characterized in that the second flow passages are arranged so as not to maintain magnetic pole symmetry or magnetic pole pair symmetry.

8. In claim 1, The rotating electric machine according to claim 1, wherein the first flow passage and the second flow passage are independently connected to the shaft flow passage.

9. In claim 1, The rotating electric machine according to claim 1, wherein the first flow passage and the second flow passage share a connection portion to the shaft flow passage.

10. A rotating electric machine comprising a rotor having a magnet disposed within a rotor core, and a stator disposed on an outer diameter side of the rotor, a rotor shaft is provided on the inner circumferential side of the rotor, and a shaft flow passage through which a refrigerant flows is provided inside the rotor shaft; The rotor is a first flow passage extending radially outward of the rotor shaft and having a first discharge port opening radially outward; a second flow passage extending radially outward from the rotor shaft, extending axially inside the rotor core, and then extending radially outward and having a second discharge port opening toward the radially outward, the first flow passage and the second flow passage are connected to the shaft flow passage; The second discharge port is disposed radially outward of the first discharge port, A rotating electric machine, characterized in that an upstream flow passage cross-sectional area of ​​the second flow passage is equal to or larger than a downstream flow passage cross-sectional area of ​​the second flow passage.

11. A rotating electric machine comprising a rotor having a magnet disposed within a rotor core, and a stator disposed on an outer diameter side of the rotor, a rotor shaft is provided on the inner circumferential side of the rotor, and a shaft flow passage through which a refrigerant flows is provided inside the rotor shaft; The rotor is a first flow passage extending radially outward of the rotor shaft and having a first discharge port opening radially outward; a second flow passage extending radially outward from the rotor shaft, extending axially inside the rotor core, and then extending radially outward and having a second discharge port opening toward the radially outward, the first flow passage and the second flow passage are connected to the shaft flow passage; The second discharge port is disposed radially outward of the first discharge port, A rotating electric machine, comprising: a flow passage cross-sectional area of ​​the first flow passage that is equal to or larger than a flow passage cross-sectional area of ​​the second flow passage.

12. A rotating electric machine comprising a rotor having a magnet disposed within a rotor core, and a stator disposed on an outer diameter side of the rotor, a rotor shaft is provided on the inner circumferential side of the rotor, and a shaft flow passage through which a refrigerant flows is provided inside the rotor shaft; The rotor is a first flow passage extending radially outward of the rotor shaft and having a first discharge port opening radially outward; a second flow passage extending radially outward from the rotor shaft, extending axially inside the rotor core, and then extending radially outward and having a second discharge port opening toward the radially outward, the first flow passage and the second flow passage are connected to the shaft flow passage; The second discharge port is disposed radially outward of the first discharge port, the rotor shaft is provided with a first shaft passage hole communicating with the first passage and a second shaft passage hole communicating with the second passage, A rotating electric machine, comprising: a first shaft passage hole having a cross-sectional area smaller than or equal to a cross-sectional area of ​​the second shaft passage hole.

13. A rotating electric machine comprising: a rotor having a magnet disposed within a rotor core; and a stator disposed on an outer diameter side of the rotor, a rotor shaft is provided on the inner circumferential side of the rotor, and a shaft flow passage through which a refrigerant flows is provided inside the rotor shaft; The rotor is a first flow passage extending radially outward of the rotor shaft and having a first discharge port opening radially outward; a second flow passage extending radially outward from the rotor shaft, extending axially inside the rotor core, and then extending radially outward and having a second discharge port opening toward the radially outward, the first flow passage and the second flow passage are connected to the shaft flow passage; The second discharge port is disposed radially outward of the first discharge port, a first end plate disposed on one axially outer side of the rotor core, and a second end plate disposed on one axially outer side of the first end plate, a rotor core that is disposed between the first end plate and the second end plate, and a rotor core that is disposed between the first end plate and the second end plate, the rotor core being configured to receive the first and second flow paths, and a rotor core that is disposed between the first end plate and the second end plate, the rotor core being configured to receive the first and second flow paths, the rotor core being configured to receive the first and second flow paths, the rotor core being configured to receive the first and second end plate, and the rotor core being configured to receive the first and second end plate, ... and the rotor core being configured to receive the first and second end plate, the rotor core being

14. In claim 1, The rotating electric machine is characterized in that one axial end of the rotor shaft is open and the other axial end is solid.

15. In claim 14, a refrigerant pump connected to an opening at one end of the rotor shaft,

16. A vehicle drive device that drives a vehicle, A vehicle drive device comprising a rotating electric machine according to any one of claims 1 to 15.

Images