Cooling device and flying object

Abstract

To provide a cooling device capable of satisfactorily cooling a rotary electric machine, and a flying object.SOLUTION: A cooling device (32) includes: a first storage section (130); a flow path section (132A); a second storage section (134); and a pump (136). The first storage section stores oil. The flow path section guides the oil stored in the first storage section to a shaft (116) via a first bearing (118A), and guides the oil guided to the shaft to a second bearing (118B). The second storage section stores the oil guided to the second bearings. The pump sends the oil that has reached the second storage section to the first storage section.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a cooling device and an air vehicle. [Background technology]

[0002] Patent Document 1 below discloses a cooling system for a rotating electric machine in an eVTOL aircraft. The cooling system has an oil flow path and a heat exchanger. The oil flow path guides oil flowing out of the heat exchanger to the rotating electric machine via a gearbox, and then guides the oil guided to the rotating electric machine to the heat exchanger via the gearbox. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 1,161,3350 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 merely discloses an oil flow path that guides oil flowing out of a heat exchanger to a rotating electrical machine via a gearbox, and then guides the oil guided to the rotating electrical machine back to the heat exchanger via the gearbox. Recently, there has been a demand for a cooling device that can effectively cool rotating electrical machines.

[0005] The present invention aims to solve the above-mentioned problems. [Means for solving the problem]

[0006] A first aspect of the present disclosure is a cooling device for cooling a rotating electric machine including a shaft arranged along a vertical direction and a rotor fixed to the shaft, comprising: a first storage section for storing oil, which is arranged above the rotor and above a first bearing that rotatably supports the shaft; a flow path section that guides the oil stored in the first storage section to the shaft via the first bearing and guides the oil guided to the shaft to a second bearing below the rotor that rotatably supports the shaft; a second storage section that is arranged below the second bearing and stores the oil guided to the second bearing; and a pump that sends the oil that reaches the second storage section to the first storage section.

[0007] A second aspect of the present disclosure is an aircraft including the cooling device according to the first aspect and the rotating electric machine. [Effects of the Invention]

[0008] This makes it possible to provide a cooling device and an aircraft that can effectively cool a rotating electrical machine. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of the aircraft. [Figure 2] FIG. 2 is a diagram showing the configuration of the rotating electrical machine and the cooling device. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a diagram showing the flow of oil. DETAILED DESCRIPTION OF THE INVENTION

[0010] [1 Overall configuration of the aircraft 10] 1 is a perspective view of an aircraft 10. In this embodiment, the aircraft 10 is an eVTOL aircraft, but is not limited to this. For example, the aircraft 10 may be a multicopter.

[0011] The aircraft 10 comprises a fuselage 12, a front wing 14, a rear wing 16, multiple booms 18, multiple propeller units 20 for takeoff and landing, and multiple propeller units 22 for cruising. The fuselage 12 is long in the longitudinal direction. The front wing 14 is located forward of the midsection of the fuselage 12 in the longitudinal direction. The front wing 14 is connected to the upper part of the fuselage 12. The rear wing 16 is located rearward of the midsection of the fuselage 12 in the longitudinal direction. The rear wing 16 is connected to the fuselage 12 via a pylon 24.

[0012] The multiple booms 18 each extend in the fore-and-aft direction. The multiple booms 18 include a right boom 18R and a left boom 18L. The right boom 18R is disposed to the right of the fuselage 12. The right boom 18R curves in an arc toward the right. The right boom 18R is connected to the right wing tip of the front wing 14 and is connected to the right wing of the rear wing 16. The left boom 18L is disposed to the left of the fuselage 12. The left boom 18L curves in an arc toward the left. The left boom 18L is connected to the left wing tip of the front wing 14 and is connected to the left wing of the rear wing 16. Note that the right boom 18R and the left boom 18L may be straight.

[0013] Each boom 18 is provided with a plurality of propeller devices 20. In this embodiment, each boom 18 is provided with four propeller devices 20. However, each boom 18 may be provided with two, three, five or more propeller devices 20. In each boom 18, the four propeller devices 20 are arranged at intervals in the extension direction of the boom 18.

[0014] Each of the multiple propeller devices 20 has an identically structured housing section 26, propeller 28, rotating electric machine 30, and cooling device 32. The housing section 26 is configured to include a frame that forms the skeleton of the boom 18 and a fairing that covers the frame. The housing section 26 houses the rotating electric machine 30 and the cooling device 32. The propeller 28 is located above the housing section 26 and is rotatably attached to the housing section 26. The rotating electric machine 30 rotates the propeller 28. The cooling device 32 cools the rotating electric machine 30.

[0015] The fuselage 12 is equipped with a plurality of propeller devices 22. In this embodiment, the fuselage 12 is equipped with two propeller devices 22. The fuselage 12 may be equipped with one or three or more propeller devices 22. The two propeller devices 22 are arranged side by side on the left and right at the rear end of the fuselage 12.

[0016] [2. Configuration of the Rotating Electric Machine 30 and the Cooling Device 32] FIG. 2 is a diagram showing the configuration of the rotating electric machine 30 and the cooling device 32. The rotating electric machine 30 is fixed with its axis (center of rotation) X aligned vertically. For example, the rotating electric machine 30 is fixed to the frame of the accommodation section 26 (see FIG. 1). Driving power is supplied to the rotating electric machine 30 from a power source via an inverter circuit. The rotating electric machine 30 rotates around its axis X in a first rotation direction D1 or a second rotation direction D2 depending on the driving power. The rotating electric machine 30 has a housing 110, a stator 112, a rotor 114, a shaft 116, and two bearings 118.

[0017] The housing 110 is formed by combining multiple members. The housing 110 accommodates a stator 112, a rotor 114, and a shaft 116. The stator 112 is fixed to the housing 110. The rotor 114 is disposed inside the stator 112 and is fixed to the shaft 116. The rotor 114 rotates in response to driving power supplied from a power source.

[0018] The shaft 116 extends vertically. The shaft 116 is rotatably supported relative to the housing 110 by two bearings 118. The shaft 116 rotates integrally with the rotor 114. The upper end of the shaft 116 is located in a gearbox 126. The gearbox 126 has multiple gears (not shown) that connect the shaft 116 of the rotating electric machine 30 to a propeller rotating shaft 28X provided on the propeller 28. The multiple gears reduce the rotational speed of the shaft 116 and transmit power to the propeller rotating shaft 28X.

[0019] Each of the two bearings 118 includes an outer ring 120, an inner ring 122, and rolling elements 124. One of the two bearings 118 is a first bearing 118A that rotatably supports the shaft 116 above the rotor 114. The other of the two bearings 118 is a second bearing 118B that rotatably supports the shaft 116 below the rotor 114.

[0020] The cooling device 32 is a device that cools the rotating electrical machine 30. The cooling device 32 has a first reservoir 130, an oil flow path 132, a second reservoir 134, a pump 136, and a heat dissipation portion 138.

[0021] The first reservoir 130 is a portion that stores oil. In this embodiment, the oil can function as a lubricant for the gearbox 126 and the bearing 118, and can also function as a refrigerant that cools the rotating electrical machine 30. The first reservoir 130 is provided above the first bearing 118A. The first reservoir 130 is provided inside the housing 110, but may also be provided outside the housing 110.

[0022] The first reservoir 130 has a reservoir space SP1 that stores oil. The reservoir space SP1 is surrounded by a bottom surface F1 of the first reservoir 130, an upper surface F2 of the first reservoir 130, and a peripheral side surface F3 of the first reservoir 130. The reservoir space SP1 is located above an accommodation space SP2 that accommodates the stator 112 and the rotor 114.

[0023] The gear box 126 is provided inside the first storage section 130 (storage space SP1). The oil stored inside the first storage section 130 is supplied to the gear box 126. The liquid level of the oil stored inside the first storage section 130 is located at least above the bottom surface of the gear box 126. Preferably, the liquid level of the oil stored inside the first storage section 130 is located above the gear box 126. Above the liquid level of the oil stored inside the first storage section 130 is an air layer. In other words, there is an air layer inside the first storage section 130.

[0024] A first air vent passage 131 is connected to the first storage portion 130. The first air vent passage 131 communicates between the inside of the first storage portion 130 and the outside of the first storage portion 130 (housing 110).

[0025] The oil flow path 132 is a flow path for flowing oil. The oil flow path 132 includes five flow path sections 132A, 132B, 132C, 132D, and 132E. The flow path section 132A guides the oil stored in the first storage section 130 to the shaft 116 via the first bearing 118A, and guides the oil guided to the shaft 116 to the second bearing 118B. The flow path section 132B guides the oil guided to the second bearing 118B to the second storage section 134. The flow path section 132C guides the oil guided to the second storage section 134 to the pump 136. The flow path section 132D guides the oil sent from the pump 136 to the first storage section 130. The flow path section 132E guides the oil in the accommodation space SP2 to the second storage section 134.

[0026] Second reservoir 134 is a portion that stores oil. Second reservoir 134 is provided below second bearing 118B. Second reservoir 134 is provided inside housing 110, but may be provided outside housing 110.

[0027] The second reservoir 134 has a reservoir space SP3 that stores oil. The reservoir space SP3 is surrounded by a bottom surface F10 of the second reservoir 134, an upper surface F20 of the second reservoir 134, and a peripheral side surface F30 of the second reservoir 134. The reservoir space SP3 is located below the accommodation space SP2. One end of the flow path portion 132C is connected to a lower portion of the peripheral side surface F30 of the second reservoir 134.

[0028] A second air vent passage 135 is connected to the second storage portion 134. The second air vent passage 135 communicates between the interior of the second storage portion 134 and the outside of the second storage portion 134 (housing 110). The portion of the second air vent passage 135 that opens into the second storage portion 134 is located higher than the portion of the flow path portion 132C that opens into the second storage portion 134. The second air vent passage 135 does not necessarily have to be provided.

[0029] Oil flows from the second bearing 118B into the interior (storage space SP3) of the second storage portion 134. The liquid level of the oil stored inside the second storage portion 134 is located between the portion of the second air vent passage 135 that opens into the second storage portion 134 and the portion of the flow path portion 132C that opens into the second storage portion 134. An air layer is located above the liquid level of the oil stored inside the second storage portion 134. In other words, there is an air layer inside the second storage portion 134. If the second air vent passage 135 is not provided, there may not be an air layer inside the second storage portion 134.

[0030] Pump 136 sucks oil from flow path portion 132C and sends the sucked oil to flow path portion 132D. Pump 136 is provided outside housing 110. For example, pump 136 is fixed to a frame or the like within storage portion 26 (see FIG. 1).

[0031] The heat dissipation section 138 is a section that dissipates heat of the oil to the outside. The heat dissipation section 138 may be a radiator. The heat dissipation section 138 is provided outside the housing 110. For example, the heat dissipation section 138 is fixed to a frame or the like within the accommodating section 26 (see FIG. 1). The heat dissipation section 138 is arranged in the flow path section 132D, but may also be arranged in the flow path section 132C.

[0032] The flow path portion 132A of the oil flow path 132 described above is made up of a first partial flow path 140, a second partial flow path 142, a third partial flow path 144, and a fourth partial flow path 146.

[0033] First partial flow path 140 includes a part of first bearing 118A. More specifically, one end (upstream end) of first partial flow path 140 includes a portion between outer ring 120 of first bearing 118A and inner ring 122 of first bearing 118A. A portion of the upper end of first bearing 118A between outer ring 120 and inner ring 122 opens to the bottom surface F1 of first reservoir 130.

[0034] The second partial flow path 142 is a partial flow path that guides the oil that has reached the first bearing 118A to the shaft 116. One end (upstream end) of the second partial flow path 142 is connected to a portion of the lower end of the first bearing 118A between the outer ring 120 and the inner ring 122. The other end (downstream end) of the second partial flow path 142 opens into the gap between the outer circumferential surface of the shaft 116 and the housing 110. In this embodiment, the second partial flow path 142 is formed in the housing 110, but is not limited to this.

[0035] The third partial flow path 144 is a partial flow path formed in the shaft 116. The third partial flow path 144 has an inlet 150, an outlet 152, and an internal cavity 154.

[0036] The inlet 150 is an opening for introducing oil that has passed through the first bearing 118A. The inlet 150 is located on the side surface of the shaft 116 at a position below the first bearing 118A. A plurality of inlets 150 are formed at intervals in the circumferential direction of the shaft 116. The inlets 150 periodically face the downstream end of the second partial flow path 142 in accordance with the rotation of the shaft 116. When the inlet 150 and the downstream end of the second partial flow path 142 face each other, the inlet 150 and the second partial flow path 142 are in communication.

[0037] One of the multiple inlets 150 may face the downstream end of the second partial flow path 142 when the shaft 116 is stationary. The inlets 150 may be formed in a continuous ring shape in the circumferential direction of the shaft 116. When the inlets 150 are formed in a continuous ring shape in the circumferential direction of the shaft 116, the inlets 150 face the downstream end of the second partial flow path 142 regardless of the rotation of the shaft 116.

[0038] The outlet 152 is a port that discharges the oil introduced from the inlet 150. The outlet 152 is located on the side surface of the shaft 116 between the inlet 150 and the second bearing 118B. A plurality of outlets 152 are formed at intervals in the circumferential direction of the shaft 116. The number of outlets 152 is the same as the number of inlets 150. The outlets 152 periodically face the upstream end of the fourth partial flow path 146 in accordance with the rotation of the shaft 116.

[0039] One of the multiple outlets 152 may face the upstream end of the fourth partial flow path 146 when the shaft 116 is located at the initial position. Alternatively, the outlet 152 may be formed in a continuous ring shape in the circumferential direction of the shaft 116. In this case, the outlet 152 faces the upstream end of the fourth partial flow path 146 regardless of the rotation of the shaft 116. When the outlet 152 and the upstream end of the fourth partial flow path 146 face each other, the outlet 152 and the fourth partial flow path 146 are in communication with each other.

[0040] The internal cavity 154 communicates with the inlet 150 and the outlet 152. A plurality of internal cavities 154 are formed at intervals in the circumferential direction of the shaft 116. The number of internal cavities 154 is the same as the number of inlets 150 and the same as the number of outlets 152. One end (upstream end) of each internal cavity 154 is connected to one inlet 150. The other end (downstream end) of each internal cavity 154 is connected to one outlet 152.

[0041] The number of internal cavities 154 may be one. In this case, the upstream end of the internal cavity 154 communicates with the plurality of inlets 150. The downstream end of the internal cavity 154 communicates with the plurality of outlets 152.

[0042] Fig. 3 is a diagram showing a cross section taken along line III-III in Fig. 2. The multiple internal cavities 154 are formed in a portion of the shaft 116 excluding the central portion 116C. The outer shape of the central portion 116C may be an inscribed circle inscribed in the multiple internal cavities 154 in a cross section perpendicular to the axis X of the shaft 116. The diameter D of the central portion 116C is equal to or greater than the radius R of the shaft 116.

[0043] 2, the fourth partial flow path 146 is a partial flow path that guides the oil discharged from the outlet 152 to the second bearing 118B. One end (upstream end) of the fourth partial flow path 146 opens into the gap between the outer peripheral surface of the shaft 116 and the housing 110. The other end (downstream end) of the fourth partial flow path 146 opens into a portion of the upper end of the second bearing 118B between the outer ring 120 and the inner ring 122. In this embodiment, the first partial flow path 140 is formed in the housing 110, but is not limited to this.

[0044] 4 is a diagram showing the flow of oil. The oil stored in the first reservoir 130 flows by gravity through the flow path 132A and reaches the second bearing 118B.

[0045] First, the oil stored in the first reservoir 130 passes through the first partial flow path 140 and flows into the space between the outer ring 120 and the inner ring 122 at the upper end of the first bearing 118A. The oil that flows into the space between the outer ring 120 and the inner ring 122 lubricates the first bearing 118A. The oil that lubricates the first bearing 118A flows into the second partial flow path 142 from the lower end of the first bearing 118A and flows through the second partial flow path 142. The oil flowing through the second partial flow path 142 flows out from the downstream end of the second partial flow path 142 and into the inlet 150 of the shaft 116 that faces the downstream end. The oil that flows into the inlet 150 flows through the internal cavity 154. The oil flowing through the internal cavity 154 flows out from the outlet 152 and into the upstream end of the fourth partial flow path 146 that faces the outlet 152. The oil that has flowed into the upstream end of the fourth partial flow path 146 flows through the fourth partial flow path 146 and reaches the second bearing 118B.

[0046] The oil that reaches the second bearing 118B lubricates the second bearing 118B. The oil lubricating the second bearing 118B flows from the lower end of the second bearing 118B to the flow path portion 132B, and then is stored in the second storage portion 134. The oil stored in the second storage portion 134 is sent to the first storage portion 130 when the pump 136 is driven. The pump 136 is driven, for example, when the rotating electric machine 30 is driven.

[0047] The rotating electric machine 30 generates heat when driven. In particular, the amount of heat generated by the rotor 114 is greater than that of the other parts of the rotating electric machine 30. The heat generated by the rotor 114 is absorbed by the oil flowing through the internal cavity 154 formed in the shaft 116. This cools the rotor 114. The oil that has absorbed the heat is dissipated in the heat dissipation section 138 and then returned to the first storage section 130.

[0048] When the rotating electric machine 30 is driven to rotate the shaft 116, a first state and a second state can occur alternately. In the first state, the inlet 150 of the shaft 116 and the downstream end of the second partial flow path 142 face each other. In the second state, the inlet 150 of the shaft 116 and the downstream end of the second partial flow path 142 do not face each other. When the rotating electric machine 30 is stopped, the first state or the second state continues. In the second state, when oil flows out from the downstream end of the second partial flow path 142, the oil flows along the outer circumferential surface of the shaft 116 without flowing into the inlet 150.

[0049] The oil flowing along the outer circumferential surface of the shaft 116 is stored in the second storage portion 134 via the flow path portion 132E.

[0050] As described above, the cooling device 32 of this embodiment includes the first storage section 130, the flow path section 132A, the second storage section 134, and the pump 136. The first storage section 130 stores oil. The flow path section 132A guides the oil stored in the first storage section 130 to the shaft 116 via the first bearing 118A, and then guides the oil guided to the shaft 116 to the second bearing 118B. The second storage section 134 stores the oil guided to the second bearing 118B. The pump 136 sends the oil that reaches the second storage section 134 to the first storage section 130. This allows the bearing 118 to be lubricated and the rotor 114 to be cooled. This eliminates the need to provide separate equipment for circulating the oil that lubricates the bearing 118 and equipment for circulating the oil through the coil used to cool the rotor 114, thereby contributing to a more compact cooling device 32.

[0051] Furthermore, in this embodiment, the first air vent passage 131 is connected to the first storage portion 130. This allows oil to flow smoothly in the flow path portion 132A. When the second air vent passage 135 is connected to the second storage portion 134 in addition to the first air vent passage 131 being connected to the first storage portion 130, oil can flow more smoothly in the flow path portion 132A.

[0052] Moreover, in this embodiment, the gear box 126 is provided inside the first reservoir 130. This allows the oil that lubricates the gear box 126 to be used as the lubricating oil for the bearings 118 and as the refrigerant for the rotor 114. This contributes to the miniaturization of the cooling device 32, since it is not necessary to provide separate equipment for circulating the oil that lubricates the gear box 126 and equipment for circulating the oil used to lubricate the bearings 118 and cool the rotor 114.

[0053] In addition, in this embodiment, the shaft 116 is formed with an inlet 150, an outlet 152, and an internal cavity 154. As a result, heat generated by the rotor 114 is absorbed by the oil flowing through the internal cavity 154, thereby cooling the rotor 114. That is, according to this embodiment, the rotor 114 can be sufficiently cooled.

[0054] In this embodiment, inlet 150 is formed in a portion below first bearing 118A on the side surface of shaft 116. Outlet 152 is formed between inlet 150 and second bearing 118B on the side surface of shaft 116. This allows oil to flow into the interior of shaft 116 by gravity.

[0055] In this embodiment, the inlet port 150, the outlet port 152, and the internal cavity 154 are each formed at multiple locations spaced apart in the circumferential direction of the shaft 116. This makes it easier to circulate oil inside the shaft 116.

[0056] Furthermore, in this embodiment, the multiple internal cavities 154 are formed in areas of the shaft 116 excluding the central portion 116C. This allows the internal cavities 154 to be closer to the rotor 114 than when the central portion 116C is the internal cavities 154. This allows the cooling efficiency of the rotor 114 to be improved.

[0057] Furthermore, in this embodiment, the diameter D of the central portion 116C is equal to or greater than the radius R of the shaft 116. This allows oil to circulate inside the shaft 116 while preventing a decrease in the durability of the shaft 116.

[0058] The following additional notes are further disclosed regarding the above embodiment.

[0059] (Appendix 1) The cooling device (32) of the present disclosure is a cooling device that cools a rotating electric machine (30) including a shaft (116) arranged along a vertical direction and a rotor (114) fixed to the shaft, and is equipped with: a first storage section (130) that stores oil and is arranged above the rotor and above a first bearing (118A) that rotatably supports the shaft; a flow path section (132A) that guides the oil stored in the first storage section to the shaft via the first bearing and guides the oil guided to the shaft to a second bearing (118B) below the rotor that rotatably supports the shaft; a second storage section (134) that is arranged below the second bearing and stores the oil guided to the second bearing; and a pump (136) that sends the oil that has reached the second storage section to the first storage section.

[0060] (Appendix 2) In the cooling device according to Supplementary Note 1, a first air vent passage (131) that communicates the inside of the first storage portion with the outside of the first storage portion may be connected to the first storage portion.

[0061] (Appendix 3) In the cooling device according to Supplementary Note 2, a second air vent passage (135) that communicates the inside of the second storage portion with the outside of the second storage portion may be connected to the second storage portion.

[0062] (Appendix 4) In the cooling device according to Supplementary Note 1, a gear box (126) may be provided inside the first storage section.

[0063] (Appendix 5) In the cooling device described in Appendix 1, the shaft may be formed with an inlet (150) for introducing the oil that has passed through the first bearing, an outlet (152) for discharging the oil introduced from the inlet, and an internal cavity (154) communicating with the inlet and the outlet.

[0064] (Appendix 6) In the cooling device described in Appendix 5, the inlet may be formed in a portion of the side surface of the shaft below the first bearing, and the outlet may be formed in a portion of the side surface of the shaft below the inlet.

[0065] (Appendix 7) In the cooling device according to Supplementary Note 5, the inlet, the outlet, and the internal cavity may each be formed in plurality at intervals in the circumferential direction of the shaft.

[0066] (Appendix 8) In the cooling device according to Supplementary Note 7, the plurality of internal cavities may be formed in a portion of the shaft excluding a central portion (116C).

[0067] (Appendix 9) In the cooling device according to Supplementary Note 8, the diameter (D) of the central portion may be equal to or greater than the radius (R) of the shaft.

[0068] (Appendix 10) The aircraft (10) of the present disclosure includes the cooling device described in any one of Supplementary Notes 1 to 9 and the rotating electric machine.

[0069] Although the present disclosure has been described in detail, the present disclosure is not limited to the individual embodiments described above. Various additions, substitutions, modifications, partial deletions, etc. are possible in these embodiments without departing from the gist of the present disclosure or the spirit of the present disclosure derived from the content of the claims and their equivalents. These embodiments can also be implemented in combination. For example, in the above-described embodiments, the order of each operation and the order of each process are shown as examples and are not limited to these. The same applies when numerical values ​​or mathematical expressions are used in the description of the above-described embodiments. [Explanation of symbols]

[0070] 10...Flying object 30...Rotating electric machine 32...cooling device 110...housing 112... Stator 114... Rotor 116...shaft 116C...center 118A...First bearing 118B...Second bearing 120...Outer ring 122...Inner ring 124...rolling element 126...gearbox 130...first reservoir 132...oil flow path 132A, 132B, 132C, 132D...flow path section 134... Second reservoir 136... Pump 138...heat dissipation section 150...inlet 152… Outlet port 154… Internal cavity

Claims

1. A cooling device that cools a rotating electric machine including a shaft disposed along a vertical direction and a rotor fixed to the shaft, a first reservoir that is provided above the rotor and above a first bearing that rotatably supports the shaft, and that reservoirs oil; a flow path that guides the oil stored in the first storage portion to the shaft via the first bearing, and guides the oil that has been guided to the shaft to a second bearing that rotatably supports the shaft below the rotor; a second reservoir provided below the second bearing and configured to retain the oil guided to the second bearing; a pump that sends the oil that has reached the second reservoir to the first reservoir; A cooling device comprising:

2. 2. The cooling device according to claim 1, a first air vent passage communicating the inside of the first storage portion with the outside of the first storage portion, the first air vent passage being connected to the first storage portion;

3. 3. The cooling device according to claim 2, A second air vent passage communicating the inside of the second storage portion with the outside of the second storage portion is connected to the second storage portion.

4. 2. The cooling device according to claim 1, A cooling device, wherein a gearbox is provided inside the first storage section.

5. 2. The cooling device according to claim 1, A cooling device in which the shaft is formed with an inlet for introducing the oil that has passed through the first bearing, an outlet for discharging the oil introduced from the inlet, and an internal cavity communicating with the inlet and the outlet.

6. 6. The cooling device according to claim 5, the inlet is formed in a portion of the side surface of the shaft below the first bearing, The outlet is formed in a portion of the side surface of the shaft below the inlet.

7. 6. The cooling device according to claim 5, A cooling device, wherein the inlet, the outlet, and the internal cavity are each formed in plurality at intervals in the circumferential direction of the shaft.

8. 8. The cooling device according to claim 7, A cooling device, wherein the plurality of internal cavities are formed in a portion of the shaft excluding a central portion.

9. 9. The cooling device according to claim 8, A cooling device wherein the diameter of the central portion is equal to or greater than the radius of the shaft.

10. An aircraft comprising: the cooling device according to any one of claims 1 to 9; and the rotating electric machine.

Images