JP5892091B2 - Multi-gap rotating electric machine - Google Patents

Description

  The present invention relates to a multi-gap rotating electric machine suitable for use in, for example, an electric motor or generator for a vehicle.

As a prior art, there is a motor described in Patent Document 1.
This motor is a double stator type motor in which an inner stator and an outer stator are arranged with gaps on the inner diameter side and outer diameter side of the rotor, respectively, and generates a higher torque than a single stator type motor. Is possible.
In addition, the motor employs a structure that takes cooling into consideration so that heat generated by the inner and outer stators is conducted to the motor housing and is radiated from the motor housing to the outside.

JP 2007-282331 A

By the way, when further improving the cooling performance in order to reduce the size and increase the output of the motor, a fluid cooling structure in which oil or the like is directly injected to the motor components in the housing is conceivable.
However, the cooling performance cannot be improved in the following points, and as a result, there is a problem that a small size and high output cannot be achieved. The main heat source of the motor is the stator, but the inner stator has a smaller surface area and less heat transfer path than the outer stator, and the entire inner surface of the inner stator is in contact with the bearing case. The structure is small and difficult to dissipate heat. For this reason, it is necessary to suppress the temperature of the motor component including the coil within an allowable value by suppressing the amount of heat generated by the resistance of the coil, and it is necessary to increase the cross-sectional area of the coil, that is, to reduce the resistance. As a result, the entire motor becomes large for the output.
The present invention has been made based on the above circumstances, and an object of the present invention is to provide a small and high output multi-gap rotating electric machine having excellent cooling performance.

The present invention includes a rotary shaft that is rotatably supported by a frame via a bearing, a rotor disk fixed to one end surface in the axial direction, and an annular rotor that is coupled to the rotary shaft via the rotor disk, An inner stator and an outer stator each having an inner core and an outer core arranged with gaps on the inner side and the outer side in the radial direction of the rotor, and having stator windings wound around the inner core and the outer core, respectively; A space that opens a part or the entire inner peripheral surface of the inner core (hereinafter referred to as an inner diameter side space) is secured on the inner diameter side of the inner stator, and is provided outside the frame. have more first oil introduction passage for introducing oil into the inner diameter side space, the first oil introduction path, the axial center portion of the rotary shaft oil inlet is opened to the axial end surface of the rotary shaft Axially And axial channels that are set, and the radial flow path that will be extended in the radial direction of the outer rotating shaft in communication with the axial passage, the oil on the inner diameter side space communicates with the radial flow passage The oil outlet has an oil outlet that opens, and the oil outlet is formed obliquely with respect to a radial direction orthogonal to the axial direction of the rotating shaft .

According to said structure, the inner diameter side space is ensured in the inner diameter side of an inner side stator, and a part or whole surface of the inner peripheral surface of an inner core is open | released without being supported by a flame | frame etc. “Open” means a state in which a part or the whole of the inner peripheral surface of the inner core is exposed to the inner diameter side space without coming into contact with a support member such as a frame that supports the inner stator.
Thereby, since the inner stator can be directly oil-cooled by introducing the oil into the inner diameter side space through the first oil introduction path, the cooling performance is improved as compared with the prior art of Patent Document 1. Also, not only the oil contacts the inner peripheral surface of the inner core, but also the stator contacts (especially the coil end) wound around the inner core so that the stator winding cools directly with oil. You can also In addition, since the contact area with oil increases, so that the area of the inner peripheral surface of the inner core open | released by the internal diameter side space is large, it cannot be overemphasized that cooling performance can be improved more.

1 is a longitudinal sectional view of a motor according to Embodiment 1. FIG. 1 is an overall configuration diagram schematically showing an oil cooling device according to Embodiment 1. FIG. 1 is an overall configuration diagram schematically showing an oil cooling device according to Embodiment 1. FIG. 6 is a half sectional view of a motor according to Embodiment 2. FIG. It is VV sectional drawing of the motor shown in FIG. 6 is a half sectional view of a motor according to Embodiment 3. FIG. It is XI-XI sectional drawing of the motor shown in FIG. 7 is a longitudinal sectional view of a motor according to Embodiment 4. FIG. 7 is a longitudinal sectional view of a motor according to Embodiment 4. FIG. FIG. 10 is a longitudinal sectional view of a motor according to a fifth embodiment. FIG. 10 is a longitudinal sectional view of a motor according to a sixth embodiment.

  The mode for carrying out the present invention will be described in detail with reference to the following examples.

Example 1
In the first embodiment, an example in which the multi-gap rotating electrical machine of the present invention is applied to a traveling motor disposed between an engine and a transmission of a hybrid vehicle, for example, will be described.
As shown in FIG. 1, the motor 1 of the first embodiment is fixed to a motor frame 2, a shaft 4 that is rotatably supported by the motor frame 2 via a pair of bearings 3, and one end surface in the axial direction. An annular rotor 6 connected to the shaft 4 via a rotor disk 5 is disposed, and the rotor 6 is arranged in a U-shaped cross section with gaps on both the inner and outer radial sides and the other axial end side. And a three-phase stator winding (described later) wound around the stator core.

The shaft 4 is connected, for example, directly between a crankshaft of an engine (not shown) and a driven shaft of a transmission via a clutch. The shaft 4 has a large shaft diameter portion 4a formed with a large outer diameter at the central portion in the axial direction.
The rotor disk 5 is made of, for example, a nonmagnetic SUS material, and supports the rotor 6 coaxially with the shaft 4. The rotor disk 5 has a cylindrical disk fixing part 5a fixed to the outer peripheral surface of the large shaft diameter part 4a by welding or the like, and extends from the disk fixing part 5a to one end side in the axial direction of the rotor 6 so as to be rotor 6. Is supported on the axial end face. The rotor 6 and the rotor disk 5 are fixed by, for example, through bolts or rivets that pass through the rotor 6 in the axial direction.

The rotor 6 is, for example, a permanent magnet type rotor in which a permanent magnet is embedded in a rotor core formed by laminating a plurality of electromagnetic steel plates, or a salient pole structure (physical uneven shape) on the inner and outer circumferences of the rotor core. It is configured as a salient pole type rotor provided.
The stator core includes an inner core 7 disposed on the inner diameter side of the rotor 6, an outer core 8 disposed on the outer diameter side of the rotor 6, and an inner core 7 and an outer core 8 disposed on the other end side of the rotor 6. And the side surface core 9 connected to each other. In the inner core 7, the outer core 8, and the side core 9, the same number of slots are formed at equal pitches in the circumferential direction.
For example, the stator core is integrally provided with fixing stays (not shown) at a plurality of locations in the circumferential direction, and the fixing stays are fixed to the motor frame 2 with screws or the like.

The stator winding is formed by connecting the inner winding 10 inserted into the slot of the inner core 7, the outer winding 11 inserted into the slot of the outer core 8, and the inner winding 10 and the outer winding 11 in series. And side windings 12 inserted into the slots of the side core 9. The inner stator described in claim 1 of the present invention is configured by winding the inner winding 10 around the inner core 7, and the outer stator is configured by winding the outer winding 11 around the outer core 8. The Further, the side winding 12 is an inner / outer connecting wire according to claims 4 to 6 of the present invention, and the side stator described in claim 5 of the present invention has a side winding 9 (inner / outer connecting wire). ).
In the stator winding, one end of the three-phase coil is connected to form a neutral point, the other end is connected to a known inverter (not shown), and an exciting current is supplied through the inverter.

Next, the oil cooling of the present invention will be described.
In the motor 1 of the first embodiment, spaces through which oil flows are secured on the inner diameter side of the inner core 7, the outer diameter side of the outer core 8, and the side side of the side core 9. Hereinafter, the space secured on the inner diameter side of the inner core 7 is the inner diameter side space 13, the space secured on the outer diameter side of the outer core 8 is the outer diameter side space 14, and the side side of the side core 9 (right side in FIG. 1). The space secured in the above is called a side space 15. As shown in FIG. 1, the inner diameter side space 13 is formed between the inner peripheral surface of the inner core 7 and the outer peripheral surfaces of the shaft large diameter portion 4a and the disk fixing portion 5a. A part or the entire surface is open to the inner diameter side space 13.
The outer diameter side space 14 is formed between the outer peripheral surface of the outer core 8 and the inner peripheral surface of the motor frame 2, and a part or the entire outer peripheral surface of the outer core 8 is open to the outer diameter side space 14. .

The side space 15 is formed between an end surface on the side opposite to the rotor of the side core 9 (hereinafter referred to as a side surface of the side core 9) and the opposing surface of the motor frame 2, and a part or the entire surface of the side core 9 is a side space. 15 is open. The “opposing surface of the motor frame 2” is the side wall surface described in claim 6 of the present invention, and has a predetermined gap between the side surface winding 12 wound around the side surface core 9. It is formed to face the side surface of the side core 9 in the axial direction.
In the motor 1, a first oil introduction path 16, a second oil introduction path 17, and a third oil introduction path for introducing oil into the inner diameter side space 13, the outer diameter side space 14, and the side space 15, respectively. A path 18 is formed. An oil discharge port 19 for discharging oil introduced into the inner diameter side space 13, the outer diameter side space 14, and the side space 15 to the outside of the motor frame 2 is provided at the bottom (vertically below) of the motor frame 2. It is attached.

The first oil introduction path 16 includes an axial flow path 16A in which an oil inlet 16a is opened at the axial end surface of the shaft 4 and the axial center portion of the shaft 4 is formed in the axial direction, and the axial flow path 16A. And a radial flow path 16B extending radially inside the large shaft diameter portion 4a, and an oil outflow path 16C communicating with the radial flow path 16B and penetrating the disk fixing portion 5a. and, the outlet to become oil outlet 16b of the oil outflow passage 16C is opened at the inner diameter side space 13.
In the radial flow path 16B, the position of the oil outlet 16b moves in the circumferential direction by the rotation of the shaft 4, and therefore only one radial flow path 16B may be provided in the large shaft diameter portion 4a. As shown in FIG. 4, two large shaft diameter portions 4a can be provided penetrating in the radial direction, or three or more can be provided at equal intervals in the circumferential direction.
As shown in FIG. 1 , the oil outflow passage 16C is formed obliquely toward the coil end side (left side in the figure ) of the inner winding 10 with respect to the radial direction (vertical direction in the figure) perpendicular to the axial direction of the shaft 4. Is done.
The second oil introduction path 17 has an oil inlet 17 a that opens in the top direction of the motor frame 2 and extends vertically downward from the oil inlet 17 a, and the oil outlet 17 b in the top direction of the outer diameter side space 14. Is open.
Similar to the second oil introduction path 17, the third oil introduction path 18 has an oil inlet 18 a that opens in the top direction of the motor frame 2, and extends vertically downward from the oil inlet 18 a. The oil outlet 18b is open in the top direction.

The oil inlets 16a, 17a, 18a of the first oil introduction path 16, the second oil introduction path 17, and the third oil introduction path 18 and the oil discharge port 19 attached to the motor frame 2 are, for example, shown in FIG. Is connected to the oil circulation circuit shown in FIG. The oil circulation circuit includes an oil pump 20 for circulating oil, an oil cooler 21 for cooling the heated oil, an oil filter (not shown), and the like.
The oil circulation circuit shown in FIG. 2 is configured as an independent circulation system for cooling the motor. For example, as shown in FIG. 3, oil circulation used for lubrication, hydraulic control, and cooling of the transmission 22 is performed. It can also be shared with the circuit. That is, transmission oil (AT fluid, CVT fluid, etc.) can also be used as motor cooling oil.

(Operation and Effect of Example 1)
As shown in FIG. 1, the motor 1 according to the first embodiment includes spaces 13 and 14 through which oil can flow to the inner diameter side of the inner core 7, the outer diameter side of the outer core 8, and the side side of the side core 9. , 15 can reduce the heat generation of the stator by oil cooling. Specifically, as indicated by an arrow A in the figure, oil introduced into the inner diameter side space 13 through the first oil introduction path 16 is the inner peripheral surface of the inner core 7 and the coil end of the inner winding 10. By ejecting toward the side, the inner stator can be effectively cooled. Similarly, as indicated by an arrow B in the figure, the oil introduced into the outer diameter side space 14 through the second oil introduction path 17 is ejected to the outer peripheral surface of the outer core 8, thereby It can be cooled effectively. Further, as indicated by an arrow C in the figure, the oil introduced into the side space 15 through the third oil introduction path 18 is applied to the side winding 12 protruding from the side surface of the side core 9 and the slot of the side core 9. The side surface stator can be effectively cooled by being ejected toward the surface.

As described above, since the inner stator, the outer stator, and the side stator can be effectively oil-cooled, the cooling performance is greatly improved as compared with the prior art disclosed in Patent Document 1, and a small high-power motor 1 can be provided.
In addition, the stator core of the first embodiment is integrally provided with a fixing stay, and the fixing stay is fastened to the motor frame 2 with screws or the like, so that the inner peripheral surface of the inner core 7 and the outer periphery of the outer core 8 are fixed. The area where the surface and the side surface of the side core 9 and the motor frame 2 abut can be reduced. In other words, the area of the inner peripheral surface of the inner core 7 opened to the inner diameter side space 13, the area of the outer peripheral surface of the outer core 8 opened to the outer diameter side space 14, and the side surface core opened to the side space 15 The area of the side surface 9 can be secured widely. As a result, the contact area between the stator core and the oil increases, so that the cooling performance is further improved.

Hereinafter, other examples (Examples 2 to 6) according to the present invention will be described.
Note that parts, configurations, and the like described with the same names as those in the first embodiment are given the same numbers as those in the first embodiment, and descriptions that are the same as those in the first embodiment are omitted.
(Example 2)
As shown in FIG. 4, the second embodiment is an example in which a protrusion 23 is provided on the inner peripheral surface of the motor frame 2 where the oil outlet 17 b of the second oil introduction path 17 is opened.
The protrusion 23 guides the flow of oil ejected from the oil outlet 17b. For example, as shown in FIG. 5, the protrusion 23 is provided radially from the vicinity of the oil outlet 17b. As a result, the oil flow is not biased in a specific direction, and is guided by the protrusion 23 and diffuses radially as indicated by the arrow in the figure, so that the cooling performance for the outer stator is further improved. Note that a groove can be provided in the inner peripheral surface of the motor frame 2 in place of the protruding portion 23 being raised.

(Example 3)
As shown in FIG. 6, the third embodiment is an example in which a protrusion 24 is provided on the facing surface of the motor frame 2 facing the side surface of the side core 9.
The protrusion 24 guides the flow of oil ejected from the oil outlet 18b of the third oil introduction passage 18, and extends, for example, in the circumferential direction on the opposing surface of the motor frame 2 as shown in FIG. Is provided. As a result, the oil ejected from the oil outlet 18b can be prevented from flowing only vertically downward, and can be guided in the circumferential direction by the protrusion 24 as indicated by the arrow in the figure, so that the cooling performance for the side stator is improved. Further improve.
As in the case of the second embodiment, a groove can be formed in the facing surface of the motor frame 2 instead of raising the protruding portion 24.

Example 4
In the fourth embodiment, the second oil introduction path 17 described in the first embodiment is abolished and only the first oil introduction path 16 is provided, or the first oil introduction path 16 and the third oil introduction path 18 are provided. This is an example.
As described in the first embodiment, it is possible to effectively cool the inner stator by providing the first oil introduction path 16.
A significant difference from the first embodiment is that at least the second oil introduction path 17 is abolished and the outer diameter side space 14 is also eliminated. That is, in the outer stator, the outer peripheral surface of the outer core 8 is in contact with the entire inner peripheral surface of the motor frame 2 as shown in FIG.

Thereby, since the heat of the outer stator is transmitted to the motor frame 2, the heat of the outer stator can be suppressed by radiating heat from the motor frame 2 to the outside.
Further, since the side surface core 9 is mechanically coupled to the outer core 8 and a part of the side surface core 9 is in contact with the motor frame 2 in the side surface stator, the third oil introduction path 18 is not provided. It is possible to suppress the heat generation of the side stator. However, as shown in FIG. 9, the third oil introduction path 18 may be provided to improve the cooling performance of the side stator by oil cooling as in the first embodiment.

(Example 5)
As shown in FIG. 10, the fifth embodiment is an example in which the first oil introduction passage 16 and the second oil introduction passage 17 are provided by eliminating the third oil introduction passage 18 described in the first embodiment.
As described in the fourth embodiment, the side stator is mechanically coupled to the outer core 8 and a part of the side core 9 is in contact with the motor frame 2, so that the outer stator is oil. It is possible to suppress the heat generation of the side stator by being cooled. Therefore, even with the configuration in which the third oil introduction path 18 is eliminated, it is possible to improve the cooling performance as compared with Patent Document 1.

(Example 6)
In the sixth embodiment, as shown in FIG. 11, the stator core is composed of an inner core 7 and an outer core 8, and the second oil introduction path 17 is eliminated.
In this case, the outer core 8 has the outer peripheral surface of the outer core 8 in contact with the entire inner peripheral surface of the motor frame 2 as described in the fourth embodiment. As a result, since the heat of the outer stator is transmitted to the motor frame 2, even if the second oil introduction path 17 is eliminated, the heat generation of the outer stator can be suppressed by radiating heat from the motor frame 2.
Further, since the stator core does not have the side core 9 described in the first embodiment, the inner and outer connecting wires that connect the inner winding 10 and the outer winding 11 in series (corresponding to the side winding 12 described in the first embodiment). Is arranged in an exposed state in the side space 15. On the other hand, since the inner and outer connecting wires 12 can be directly oil-cooled by providing the third oil introduction path 18, the cooling performance can be improved as compared with Patent Document 1 even in the configuration without the side core 9.

1 Motor (Multi-gap type rotating electrical machine)
2 Motor frame (frame)
3 Bearing 4 Shaft (Rotating shaft)
5 Rotor disk 6 Rotor 7 Inner core 8 Outer core 10 Inner winding (stator winding)
11 Outer winding (stator winding)
12 Side winding (internal / external connecting wire)
13 inner diameter side space 14 outer diameter side space 15 side space 16 first oil introduction path 16A axial flow path (first oil introduction path)
16B radial flow path (first oil introduction path)
16C Oil outflow path (first oil introduction path)
16b Oil outlet 17 Second oil introduction path 18 Third oil introduction path

Claims (6)

A rotating shaft (4) rotatably supported on the frame (2) via a bearing (3);
A rotor disk (5) fixed to one end surface in the axial direction, and an annular rotor (6) connected to the rotating shaft (4) via the rotor disk (5);
The rotor (6) has an inner core (7) and an outer core (8) arranged with a gap on the inner side and the outer side in the radial direction, respectively, and the inner core (7) and the outer core ( 8) a multi-gap type rotating electrical machine (1) comprising an inner stator and an outer stator each wound with a stator winding,
On the inner diameter side of the inner stator, a space (hereinafter referred to as an inner diameter side space (13)) that opens a part or the entire inner peripheral surface of the inner core (7) is secured,
Before SL has frame (2) the first oil introduction passage for introducing oil to the outside from the inner diameter side space (13) of the (16),
The first oil introduction passage (16), said oil inlet to the axial end surface of the rotary shaft (4) (16a) is bored an axial center of the rotary shaft and opens (4) in the axial direction axial flow path (16A), and the axial flow passage wherein communicates with (16A) rotational axis (4) radial passage diameter Ru is the direction of extending to the outside of (16B), the radial flow An oil outflow passage (16C) in communication with the passage (16B) and having an oil outlet (16b) open in the inner diameter side space (13);
The multi-gap rotating electrical machine, wherein the oil outflow passage (16C) is formed obliquely with respect to a radial direction orthogonal to the axial direction of the rotating shaft (4) . In the multi-gap type rotating electrical machine (1) according to claim 1,
On the outer diameter side of the outer stator, a space (hereinafter referred to as an outer diameter side space (14)) that opens a part or the entire outer peripheral surface of the outer core (8) is secured,
The frame (2) is formed with a second oil introduction path (17) for introducing oil from the outside of the frame (2) to the outer diameter side space (14). 17) An oil inlet (17a) is opened in the ceiling direction of the frame (2), and extends vertically downward from the oil inlet (17a). The ceiling direction of the outer diameter side space (14) The multi-gap type rotating electrical machine is characterized in that the oil outlet (17b) is open. In the multi-gap type rotating electrical machine (1) according to claim 2,
On the inner peripheral surface of the frame (2) where the oil outlet (17b) of the second oil introduction path (17) opens, the oil flows out from the oil outlet (17b) to the outer diameter side space (14). A multi-gap rotating electrical machine characterized in that a protrusion (23) or a groove for guiding and diffusing oil flow is provided. In the multi-gap type rotating electrical machine (1) according to any one of claims 1 to 3,
The stator winding includes an inner winding (10) wound around the inner core (7), an outer winding (11) wound around the outer core (8), and the other end side in the axial direction. And the inner and outer connecting wires (12) connecting the inner winding (10) and the outer winding (11) across the rotor (6),
Inside the frame (2), a space (hereinafter referred to as a side space (15)) for arranging the inner and outer connecting wires (12) is secured,
The frame (2) is formed with a third oil introduction path (18) for introducing oil into the side space (15) from the outside of the frame (2). The third oil introduction path (18) The oil inlet (18a) opens in the ceiling direction of the frame (2), extends vertically downward from the oil inlet (18a), and extends in the ceiling direction of the side space (15). A multi-gap type rotating electrical machine characterized in that (18b) is opened. In the multi-gap type rotating electrical machine (1) according to claim 4,
A side core (9) connected to the inner core (7) and the outer core (8) on the other end side in the axial direction and disposed with a gap on the other end side of the rotor (6). The multi-gap rotating electric machine is characterized in that the inner and outer connecting wires (12) are wound around the side core (9) to form a side stator. In the multi-gap type rotating electrical machine (1) according to claim 4 or 5,
The frame (2) has a side wall surface defining a second end side in the axial direction of the side space (15) with a predetermined gap between the frame (2) and the inner and outer connecting wire (12). Is provided with a protrusion (24) or a groove for guiding the flow of oil flowing out from the outlet of the third oil introduction passage (18) to the side space (15) in the circumferential direction. A featured multi-gap rotating electrical machine.