Rotary electric machine

Abstract

To provide a rotary electric machine that realizes a coil temperature reduction by coil direct cooling and an improvement of assembling.SOLUTION: A rotary electric machine comprises: an annular stator core in which a plurality of slots are formed; a coil that includes a plurality of slot insertion parts inserted into each slot, and inserts the plurality of slot insertion parts into the slots different from each other; and a stator having an insulation member that is arranged between the slot and each slot insertion part of them. The coil includes a coil end part that is projected to an external part from an end surface of the stator core and connects the plurality of slot insertion parts. The coil has a transition direction surface in contact with the insulation member. Each slot includes: a coil stationary part in contact with the transition direction surface of the coil; and a space formation part which forms a space on a surface side opposite to the transition direction surface of the coil.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] While there is a demand for improving the output density of motors, when the current density increases, the center of the coil in the slot becomes the hottest, which limits the increase in output. Therefore, cooling is improved by using a cooling means such as directly spraying cooling oil on the coil in the slot. For example, the following Patent Document 1 discloses a technology for cooling a motor in a compact manner by providing a cooling jacket 6 that surrounds the coil ends 7A protruding from the front and rear ends of a stator core 5 to form a liquid-tight annular space, and engaging and positioning the end of the cooling jacket 6 on the stator core 5 side with a base plate 8. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-348594 A Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the technology described in Patent Document 1, an object of the present invention is to provide a rotating electric machine which realizes a reduction in coil temperature through direct cooling of the coil and improved ease of assembly by enabling the coil to be fixed while securing cooling path space without relying on varnish, which is an insulating material that is filled into the gap within the slot. [Means for solving the problem]

[0005] A rotating electric machine having a stator including a ring-shaped stator core in which a plurality of slots are formed, a coil having a plurality of slot insertion portions to be inserted into the slots, the coil inserting the plurality of slot insertion portions into different slots from each other, and an insulating member arranged between the slot and each of the slot insertion portions, wherein the coil has a coil end portion protruding outward from an end face of the stator core and connecting the plurality of slot insertion portions, the coil has a transition direction surface in contact with the insulating member, and the insulating member has a coil fixing portion in contact with the transition direction surface of the coil, and a space forming portion which is a space formed on the surface side of the coil opposite to the transition direction surface. Effect of the Invention

[0006] According to the present invention, it is possible to provide a rotating electric machine which realizes a reduction in coil temperature by direct cooling of the coil and improved ease of assembly. [Brief description of the drawings]

[0007] [Figure 1] Example of vehicle electric drive system and cooling configuration [Diagram 2] A cooling oil flow structure in an electric drive system according to an embodiment of the present invention. [Diagram 3] 1 is an assembly diagram of an insulating member for insertion into a slot according to an embodiment of the present invention; [Figure 4] FIG. 1 is a diagram showing the relationship between the coil and the insulating member in the slot according to an embodiment of the present invention. [Diagram 5] FIG. 1 is a diagram showing the layout of coils and insulating members in a slot according to an embodiment of the present invention. [Figure 6] Variations [Figure 7] FIG. 1 is an explanatory diagram of a stator tooth according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and appropriate omissions and simplifications have been made for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0009] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0010] (One embodiment and overall configuration) (Figure 1) The vehicle body 1 is a vehicle that travels on four tires 2. The vehicle body 1 has an electric drive system 6 that drives the tires 2, an oil cooler 7 that is connected to the electric drive system 6 via a cooling system 3 and exchanges heat with the circulating refrigerant, and a chiller 5 that is connected to the oil cooler 7 via a cooling system 4 and releases heat from the circulating refrigerant to the outside of the vehicle body 1. The electric drive system 6 is, for example, a system using a motor for transmitting power to the tires 2. The oil cooler 7 is water-cooled if the refrigerant is cooling water, and is oil-cooled if the refrigerant is cooling oil.

[0011] (Figure 2) The motor 8 has a stator 11, a rotor 12, and a reducer 20. The rotor 12 has a magnet. The stator 11 has a stator core and a coil 10, and between the stator core and the coil 10, there are a first resin member 15 which is a bobbin and a second resin member 16 which is a cuff. The first resin member 15 and the second resin member 16 are insulating members.

[0012] The rotor 12 has a rotor core, rotor end plates, a shaft, and permanent magnets. The shaft is rotatably supported by bearings. The rotor core is formed by laminating electromagnetic steel sheets (thin sheets). The reducer 20 is a mechanical device that reduces the rotational speed of the motor 8 using gears or the like and outputs the reduced rotational speed. The stator 11 and the rotor 12 may be configured to be skewed.

[0013] The cooling oil circulating inside the motor 8 moves to a flow path outside the motor 8 via a cooling oil outlet 21, passes through an oil pan 22, an oil pump 23, and the oil cooler 7 in that order, and returns to the inside of the motor 8 from a cooling oil inlet 18 of the motor 8, thereby cooling the components of the motor 8 again. In Figure 2, the flow of the cooling oil is illustrated as a cooling oil path 24.

[0014] The cooling oil path 24 will now be described. The cooling oil discharged from the motor 8 to the oil pan 22 flows to the oil pump 23, and the cooling oil pumped from the oil pump 23 is cooled by the oil cooler 7 and then flows into the motor 8 and into the coil end space flow path 19.

[0015] The coil end space flow passage 19 is, for example, a circumferentially annular space surrounded by the second resin member 16 and a housing of the stator 11. The coil end space flow passage 19 is liquid-tight except for the cooling oil inlet 18 and an opening of the second resin member 16.

[0016] The cooling oil flows from the coil end space flow passages 19 through the openings of the second resin member 16 into the intra-slot flow passages 17 of the stator 11. The cooling oil that flows into the slots of the stator 11 cools the stator 11 and is discharged into the chamber of the motor 8 from the openings of the first resin member 15 provided on the surface of the stator 11 opposite to the surface on which the second resin member 16 is provided.

[0017] The coil end space flow passage 19 may also be provided on the coil end portion side provided on the cooling oil outlet 21 side of the stator 11. The cooling oil path 24 may be present in a place other than the in-slot flow passage 17 in the stator 11, and may be provided in parallel or series to the in-slot flow passage 17, for example.

[0018] (Figure 3) FIG. 3(a) shows a first resin member 15 and a second resin member 16 being inserted into the stator 11 from opposite sides in the direction of the arrows. FIG. 3(b) shows a coil 10 being inserted into the stator 11 into which the first resin member 15 and the second resin member 16 have been inserted in the direction of the arrows after the process of FIG. 3(a). FIG. 3(c) shows a coil 10 being fixed to the stator 11 by welding after the process of FIG. 3(b) by bending the coil end of the coil 10 inserted into the stator 11.

[0019] Each first resin member 15 is inserted into a slot from one end face of the stator core of the stator 11 and positioned within the slot, so that it is positioned between the coil 10 inserted subsequently and the wall surface of the slot. A second resin member 16, which connects with the first resin member 15 inserted into the annular stator core in which multiple slots are formed, is inserted into the slot from the other end face of the stator core, and its outer periphery is held by a jig. The first resin member 15 and the second resin member 16 are connected to each other at the end face of the stator core.

[0020] The first resin members 15 are formed individually and inserted into each slot of the stator 11, while the second resin member 16 is integrally molded in a circumferential shape along the end face of the stator core. The second resin member 16 connects to the ends of the first resin members 15 inserted into each slot of the stator 11. Cooling oil for cooling the stator 11 flows into the slots of the stator 11 from the second resin member 16 side.

[0021] Coil 10 has a plurality of slot insertion portions that are inserted into slots of stator 11, and the plurality of slot insertion portions are inserted into different slots from one another. Coil 10 also has coil end portions that protrude outward from the end face of the stator core and connect the plurality of slot insertion portions together.

[0022] This makes it easier to seal the liquid-tight space for pouring cooling oil into stator 11, and prevents cooling oil from leaking into the gap between stator 11 and rotor 12.

[0023] (Fig. 4, Fig. 5) The diagram on the left side of Fig. 4 is an explanatory diagram of the coil 10 in the slot on the opening side of the second resin member 16. The diagram on the right side of Fig. 4 shows the state of the coil 10 in the slot on the opening side of the first resin member 15.

[0024] The opening of the first resin member 15 and the opening of the second resin member 16 each have a space forming portion 27 between them and the coil 10 inserted in the slot. This ensures a cooling path space in the slot and allows the cooling oil flowing into the slot to come into direct contact with the coil 10 to cool it, thereby reducing the temperature of the coil 10.

[0025] The opening of the first resin member 15 and the opening of the second resin member 16 have a coil fixing portion 28 that fixes the coil 10 to the first resin member 15 and the second resin member. The coil 10 is configured such that the coil insertion portions connected by the coil ends are inserted into predetermined slots, thereby transitioning through a plurality of slots. At this time, the layers into which the pair of coil insertion portions connected by the coil ends are inserted are different from each other in the two predetermined slots. For example, in one slot, the coil insertion portion is inserted into the first layer, and the other coil insertion portion connected to this coil insertion portion by the coil end is inserted into the second layer of another slot. Note that the pair of coil insertion portions can rotate in opposite directions in each slot, so the coil 10 has no degree of freedom of rotation.

[0026] In the coil insertion portion, the surface that comes into contact with the first resin member 15 and the second resin member 16 is defined as the transition direction surface 30 (FIG. 5). The space forming portion 27 is formed on the surface of the coil 10 opposite the transition direction surface. As the transition direction surface 30 of the coil 10 comes into contact with the coil fixing portion 28, the coil 10 has less degree of freedom, including radial and circumferential movement, and the coil 10 can be fixed by restricting the degree of rotational freedom between the predetermined slots into which the coil 10 is inserted. On the other hand, the coil fixing portion 28 alone has a degree of freedom, so that the insertion of the coil 10 is not hindered, improving the ease of assembly.

[0027] 4, the opening cross sections of the first resin member 15 and the second resin member 16 into which the same coil 10 is inserted are different from each other. This allows the coil fixing portions 28 of the first resin member 15 and the second resin member 16 to restrict the circumferential degree of freedom of the coil 10 and also restrict the rotational degree of freedom of the coil 10 between the inserted slots, thereby improving the fixation of the coil 10.

[0028] 5, the coil fixing portions 28 are provided at different positions for each layer in the radial direction of the slot. In other words, the coil fixing portions 28 are in contact with opposing surfaces of the coil 10 alternately in the circumferential direction for each layer. This contributes to preventing cracking of the first resin member 15 in the bending process associated with fixing the coil 10 to be inserted into the stator 11.

[0029] (Modification) (Figure 6) As a modified example, in the space forming portion 27, a protrusion 31 may be provided so as to protrude toward the coil 10 from the surface of the first resin member 15 facing the coil 10. Also, the coil fixing portion 28 that contacts the transition direction surface of the coil 10 may be provided with a notch 32 that does not contact any part of the transition direction surface. This promotes turbulence of the refrigerant flowing through the slot, further improving the cooling performance of the coil 10. Note that the protrusion 31 may be provided in any layer of the slot.

[0030] (Figure 7) The teeth formed between the multiple slots in the stator 11 are parallel teeth 33 whose slot-side surfaces are formed parallel to each other. This makes it possible to increase the cross-sectional area of ​​the cooling oil path in the slot, thereby improving the cooling performance of the coil 10.

[0031] According to the embodiment of the present invention described above, the following advantageous effects are achieved.

[0032] (1) A rotating electric machine 8 including a stator including an annular stator core in which a plurality of slots are formed, a coil 10 having a plurality of slot insertion parts to be inserted into the slots, the plurality of slot insertion parts being inserted into different slots from each other, and an insulating member disposed between the slot and each of the slot insertion parts, the coil 10 having a coil end part protruding outward from an end face of the stator core and connecting the plurality of slot insertion parts to each other. The coil 10 has a transition direction surface 30 in contact with the insulating member. The insulating member has a coil fixing part 28 in contact with the transition direction surface of the coil, and a space forming part 27 which is a space formed on the surface side opposite to the transition direction surface 30 of the coil. In this way, a rotating electric machine 8 can be provided which realizes a reduction in the coil temperature by direct cooling of the coil and an improvement in ease of assembly.

[0033] (2) The insulating members include a first insulating member 15 inserted into the slot from one end face of the stator core and a second insulating member 16 inserted into the slot from the other end face of the stator core, and the first insulating member 15 and the second insulating member 16 are connected to each other at the end faces of the stator core. This makes it possible to suppress leakage of refrigerant oil into the gap.

[0034] (3) The slot has a coil fixing portion 28, and the coil fixing portion 28 is provided at a different position in the radial direction of the slot for each layer of the stator 11. This makes it possible to prevent cracking of the first resin member 15 during the bending process of the coil 10.

[0035] (4) The coil fixing portion 28 has a notch 32 that does not contact a part of the transition direction surface 30, and the space forming portion 27 has a protrusion 31 that extends from the insulating member toward the coil 10. This contributes to improving the cooling performance within the slot.

[0036] (5) The teeth formed between the multiple slots are parallel teeth 33 whose slot-side surfaces are parallel to each other. This can contribute to improving the cooling performance within the slots.

[0037] (6) The second insulating member 16 is integrally formed in a circumferential shape along the end face of the stator core, and allows the cooling oil to flow into the slots, thereby preventing the cooling oil from leaking into the gaps.

[0038] The present invention is not limited to the above-described embodiment, and various modifications and other configurations can be combined without departing from the spirit of the present invention. Furthermore, the present invention is not limited to those having all of the configurations described in the above-described embodiment, and includes those in which some of the configurations are omitted. [Explanation of symbols]

[0039] 1. Vehicle body 2 Tires 3. Cooling system for electric drive system 4 Vehicle Cooling System 5 Chiller 6 Electric drive system 7 Oil cooler 8 Motor 10 Coil 11 Stator 12 Rotor 13 Shaft 14. Magnets 15 First resin member 16 Second resin member 17 Slot flow passage 18 Cooling oil inlet 19 Coil end space flow passage 20 Reducer 21 Cooling oil outlet 22 Oil pan 23 Oil pump 24 Cooling oil path 25 Welding 26 Coil bending 27 Space formation part 28 Coil fixing part 30 Transition direction plane 31 Protrusion 32 Cutout 33 Parallel Teeth

Claims

1. an annular stator core having a plurality of slots formed therein; a coil having a plurality of slot insertion portions to be inserted into the slots, the plurality of slot insertion portions being inserted into different slots; an insulating member disposed between the slot and each of the slot insertion portions, the coil has a coil end portion that protrudes outward from an end face of the stator core and connects the plurality of slot insertion portions to each other, The coil has a transition surface that contacts the insulating member, The insulating member has a coil fixing portion that contacts the transition direction surface of the coil, and a space forming portion that is a space formed on a surface side of the coil opposite to the transition direction surface. Rotating electric motor.

2. 2. The rotating electric machine according to claim 1, the insulating members include a first insulating member inserted into the slot from one end face of the stator core, and a second insulating member inserted into the slot from the other end face of the stator core, The first insulating member and the second insulating member are connected to each other at an end surface of the stator core. Rotating electric motor.

3. 2. The rotating electric machine according to claim 1, The slot has the coil fixing portion, The coil fixing portions are provided at different positions in the radial direction of the slots for each layer of the stator. Rotating electric motor.

4. 2. The rotating electric machine according to claim 1, The coil fixing portion has a notch portion that does not contact a part of the transition direction surface, The space forming portion has a protrusion extending from the insulating member toward the coil. Rotating electric motor.

5. 2. The rotating electric machine according to claim 1, The teeth formed between the plurality of slots are parallel teeth whose surfaces on the slot side are parallel to each other. Rotating electric motor.

6. 3. The rotating electric machine according to claim 2, The second insulating member is integrally formed circumferentially along the end surface of the stator core, and allows cooling oil to flow into the slots. Rotating electric motor.

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