Electric unit

Abstract

To achieve high waterproofness and high cooling performance of multiple electric components.SOLUTION: An electric unit (30) is installed on an electric vehicle. The electric unit is provided with: multiple electric devices (51, 63, 66) forming an electric drive system; and a storage case (31) in which the multiple electric devices are stored. An intake port and an exhaust port of cooling air are formed on an upper surface of the storage case, and a cooling fan (69) is provided at the intake port or the exhaust port.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electric unit. [Background technology]

[0002] In an electric vehicle, power is supplied from a battery to an electric motor via a drive unit in response to accelerator operation. One known example of this type of electric vehicle is one in which a drive unit is installed behind the battery and an electric motor is installed behind the drive unit (see, for example, Patent Document 1). In the electric vehicle of Patent Document 1, the drive unit is sandwiched between the battery and the electric motor from the front and rear. For this reason, a duct is provided from the front of the vehicle toward the drive unit, and the drive unit is cooled by the wind drawn in through the duct. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-66291 Summary of the Invention [Problem to be solved by the invention]

[0004] The electric vehicle described in Patent Document 1 has electrical equipment such as a battery, drive unit, and electric motor exposed to the outside. As a result, the electrical equipment is cooled by the wind generated when the vehicle is running, but the electrical equipment cannot be sufficiently waterproofed when the vehicle is running on flooded roads.

[0005] The present invention has been made in view of the above points, and has an object to provide an electric unit that can achieve both high waterproofing and high cooling performance for a plurality of electric components. [Means for solving the problem]

[0006] An electric unit according to one aspect of the present invention is an electric unit to be installed in an electric vehicle, the electric unit comprising: a plurality of electric devices constituting an electric drive system; and a housing case that houses the plurality of electric devices; the plurality of electric devices include an electric motor that drives the electric vehicle, a battery that supplies power to the electric motor, and an inverter that drives the electric motor to rotate; A cooling air intake and exhaust port are formed on the top surface of the housing case, and a cooling fan is provided at the intake or exhaust port. The battery is installed with a gap between the front wall and the pair of side walls of the housing case, and the intake port overlaps the battery in a plan view. This solves the above problem. [Effects of the Invention]

[0007] According to an electric unit of one aspect of the present invention, the electric devices are covered by the housing case, which prevents water from entering the electric devices even when the electric vehicle is traveling on a flooded road, etc. Furthermore, even when the electric devices are covered by the housing case, each electric device is cooled by the cooling air drawn into the housing case through the intake port. This allows the electric unit to have both high waterproofing and high cooling performance. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a left side view of an electric vehicle according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of the electric unit of the present embodiment. [Figure 3] FIG. 2 is a perspective view of an electrical device in a housing case according to the present embodiment. [Figure 4] FIG. 3 is a schematic side view showing the flow of cooling air in the electric unit of the present embodiment. [Figure 5] FIG. 2 is a schematic plan view showing the flow of cooling air in the electric unit of the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] An electric unit according to one aspect of the present invention is installed in an electric vehicle. An electric drivetrain is made up of multiple electric devices, which are housed in a housing case. By covering the multiple electric devices in the housing case, water is prevented from entering the electric devices even when the electric vehicle is traveling on flooded roads, etc. In addition, a cooling air intake and exhaust port are formed on the top surface of the housing case, and a cooling fan is provided at the intake or exhaust port. Even though the multiple electric devices are covered by the housing case, the electric devices are cooled by the cooling air drawn into the housing case through the intake port. This allows the electric unit to have both high waterproofing and high cooling performance. [Example]

[0010] Generally, the body frame of an electric vehicle is equipped with multiple electrical devices that make up the electric drivetrain. While exterior components such as cowls and covers are attached to the body frame, the lower part of the vehicle is not covered by these exterior components. Therefore, when the electric vehicle travels on flooded roads, the electrical devices inside the exterior components may become submerged in water. While waterproofing can be improved by housing the electrical devices in cases, this reduces the exposure of the electrical devices to the wind while traveling, thereby impairing their cooling performance. Thus, there is a trade-off between the cooling and waterproofing capabilities of electrical devices, and there is a need to achieve both cooling and waterproofing capabilities for electrical devices.

[0011] The present embodiment will be described in detail below with reference to the accompanying drawings. Fig. 1 is a left side view of an electric vehicle according to the present embodiment. In the following description, an ATV (All Terrain Vehicle) will be used as an example of the electric vehicle, but the type of electric vehicle is not particularly limited. In the following drawings, the arrow FR indicates the front of the vehicle, the arrow RE indicates the rear of the vehicle, the arrow L indicates the left side of the vehicle, and the arrow R indicates the right side of the vehicle.

[0012] As shown in Fig. 1, the electric vehicle 1 is configured with an electric unit 30 mounted inside a body frame 10. The body frame 10 is formed in a cradle shape, with a pair of left and right upper frames 11 and lower frames 12 connected by a pair of left and right front frames 13 and rear frames 14. A pair of left and right front wheels 23 are supported on the front frame 13 via suspension arms (not shown) and front suspensions 21. A steering shaft 22 is supported on the front frame 13, and by operating the steering shaft 22, each front wheel 23 is steered left and right.

[0013] A swing arm 25 is swingably supported on the pivot plate 15 of the rear frame 14. The swing arm 25 extends rearward from the pivot plate 15, and a rear portion of the swing arm 25 is connected to the upper frame 11 via a rear suspension 26. A pair of left and right rear wheels 27 are supported on the rear portion of the swing arm 25 via rear shafts (not shown). Rear sprockets (not shown) of the rear wheels 27 are connected to an electric motor 63 (see FIG. 3) of the electric unit 30 via a chain (not shown), and the rear wheels 27 are rotated by the electric motor 63 via the chain.

[0014] The lower portion of electric unit 30 is attached to suspension portions 16-18 of lower frame 12, and the rear portion of electric unit 30 is attached to suspension portion 19 of rear frame 14. Electric unit 30 is a unit formed by accommodating multiple electrical devices in a single housing case 31, which improves the waterproofing of the multiple electrical devices. An intake duct 48 is attached to the front top surface of housing case 31, and an exhaust duct 49 is attached to the rear top surface of housing case 31. Cooling air flowing from intake duct 48 to exhaust duct 49 improves the cooling of the multiple electrical devices inside housing case 31.

[0015] The electric unit will be described in detail with reference to Figures 2 and 3. Figure 2 is a perspective view of the electric unit of this embodiment. Figure 3 is a perspective view of the electrical equipment in the housing case of this embodiment. For ease of explanation, the housing case is shown by a dashed line in Figure 3.

[0016] As shown in Figure 2, the housing case 31 of the electric unit 30 has a left-right split structure and includes a left case half 32 and a right case half 33. A cooling air intake port 34 is formed on the front side of the top surface of the left case half 32. The rear side of the top surface of the left case half 32 is recessed in a V-shape in side view, and a cooling air exhaust port 36 is formed on a rear slope 35 of this recess. The right side of the recess in the left case half 32 bulges out from the top surfaces of the right case half 33 and the left case half 32, and this bulging portion widens the housing space of the housing case 31. The rear side of the right case half 33 is formed narrow, and a motor sprocket (not shown) is exposed at the rear side of the right case half 33.

[0017] As shown in Fig. 3, the housing case 31 of the electric unit 30 houses a plurality of electrical devices that make up the electric drive system, such as a battery 51, a DC-DC converter 61, a controller 62, an electric motor 63, and an inverter 66. A battery holder 52 is installed at the front side of the housing space of the housing case 31. The battery holder 52 is formed in a box shape with an open top, and the battery 51 is held inside the battery holder 52. Holder fixing portions 53, 54 are formed at the bottom of the battery holder 52, and the holder fixing portions 53, 54 protrude outward from the housing case 31 and are fixed to the suspension portions 16, 17 (see Fig. 4) of the lower frame 12.

[0018] A plurality of openings 55 are formed in the side of the battery holder 52, and the side of the battery 51 is exposed laterally through the plurality of openings 55. The battery case of the battery 51 is formed in a rectangular parallelepiped shape, and a plurality of battery cells are housed inside the battery case. The plurality of battery cells are charged with power for driving, and power is supplied from the battery cells to the electric motor 63. A pair of front and rear bridge plates 57, 58 are fixed to the upper part of the battery holder 52 so as to cross above the battery 51. Cushioning material (not shown) is interposed between each of the bridge plates 57, 58 and the battery 51.

[0019] A DC-DC converter 61 is installed on the right side of the upper surface of the rear bridge plate 58. The DC-DC converter 61 transforms the voltage of the direct current power output from the battery 51. A controller 62 is installed behind the DC-DC converter 61 on the rear surface of the battery holder 52. The controller 62 controls various parts of the vehicle and also controls an inverter 66 in response to accelerator operation. A predetermined gap is provided between the rear surface of the battery holder 52 and the controller 62, and a plurality of openings 56 are formed on the rear surface of the battery holder 52 facing the controller 62.

[0020] An electric motor 63 is installed at the rear side of the accommodation space of the accommodation case 31. Motor fixing portions 64, 65 (see FIG. 4 for the motor fixing portion 64) are formed at the lower and rear portions of the motor case of the electric motor 63, and suspension portions 18, 19 (see FIG. 4) of the lower frame 12 and the rear frame 14 are fixed to the motor fixing portions 64, 65. An inverter 66 is fixed to the left side of the electric motor 63, and the electric motor 63 and the inverter 66 are integrated together. The inverter 66 converts DC power from the battery 51 into AC power, which drives the electric motor 63 to rotate. The electric vehicle 1 (see FIG. 1) runs due to the rotational drive of the electric motor 63.

[0021] A cooling fan 69 is attached to the housing case 31 via a bracket 68, and the cooling fan 69 is provided at the intake port 34 (see FIG. 2) of the housing case 31. An intake duct 48 is connected to the intake port 34, and cooling air is taken into the housing case 31 through the intake duct 48 by the cooling fan 69. An exhaust duct 49 is connected to the exhaust port 36 (see FIG. 2) of the housing case 31, and the cooling air inside the housing case 31 is exhausted to the outside through the exhaust duct 49. In this way, the cooling air flows from the intake duct 48 of the housing case 31 toward the exhaust duct 49, thereby cooling each electrical device such as the battery 51.

[0022] The layout of the electrical equipment and the flow of cooling air will be described with reference to Figures 4 and 5. Figure 4 is a schematic side view showing the flow of cooling air within the electric unit of this embodiment. Figure 5 is a schematic plan view showing the flow of cooling air within the electric unit of this embodiment. Note that Figure 4 shows the left case half removed from the housing case, and Figure 5 shows the housing case without the top surface.

[0023] 4 and 5, the battery 51 is installed at the front side of the storage space of the storage case 31, and the electric motor 63 is installed at the rear side of the storage space of the storage case 31. A DC-DC converter 61 and a controller 62 are installed midway between the front and rear of the storage space of the storage case 31, and the DC-DC converter 61 and the controller 62 are positioned to the right of the center line L of the storage case 31, which extends from front to back. An inverter 66 is integrated with the electric motor 63, and the inverter 66 is positioned to the left of the center line L of the storage case 31. The intake port 34 (cooling fan 69) and the exhaust port 36 are also positioned to the left of the center line L of the storage case 31.

[0024] The battery 51 is installed with a gap between it and the front wall 41 and the pair of side walls 42, 43 of the accommodating case 31. In a plan view, the intake port 34 overlaps with the battery 51, and cooling air is blown toward the battery 51 from above. The cooling air enters the gap between the battery 51 and the front wall 41 of the accommodating case 31 and the gap between the battery 51 and the side walls 42, 43 of the accommodating case 31. The battery 51 is held in a battery holder 52, and the front surface of the battery holder 52 is cut out and multiple openings 55 are formed in the side surface of the battery holder 52, so that the battery 51 is effectively cooled by the cooling air.

[0025] At this time, the gap between the left side wall 43 of the housing case 31 and the battery 51 is larger than the gap between the right side wall 42 of the housing case 31 and the battery 51, and cooling air can easily flow rearward through the gap between the left side wall 43 of the housing case 31 and the battery 51. As described above, the intake port 34 is formed in a position biased toward the side wall 43 (left side) with respect to the center line L of the housing case 31, and the amount of cooling air flowing from the intake port 34 toward the side wall 43 is increased. Therefore, the cooling air can easily reach the inverter 66, which generates a large amount of heat, and the increased amount of cooling air reaching the inverter 66 effectively cools the inverter 66.

[0026] Furthermore, the DC-DC converter 61 and controller 62 are installed closer to the right, and the inverter 66 is installed closer to the left side wall 43. Therefore, the cooling air flowing from the intake port 34 toward the inverter 66 is not blocked by the DC-DC converter 61 and controller 62 in front of the inverter 66. This makes it easier for the cooling air to reach the DC-DC converter 61 on the battery 51. The controller 62 is installed on the rear surface of the battery holder 52, and because multiple openings 56 (see FIG. 3) are formed on the rear surface of the battery holder 52, the cooling air also reaches the controller 62 through the multiple openings 56.

[0027] The inverter 66 is installed with gaps between it and the rear wall 44 and the side wall 43 of the accommodating case 31. The inverter 66 is effectively cooled by the cooling air that enters the gap between the inverter 66 and the side wall 43 of the accommodating case 31 and the gap between the inverter 66 and the rear wall 44 of the accommodating case 31. At least a portion of the exhaust port 36 overlaps the inverter 66 in a plan view, and the cooling air is discharged from above the inverter 66. The cooling air inside the accommodating case 31 tends to gather around the inverter 66, and the cooling air is discharged to the outside from the exhaust port 36 while hitting the inverter 66, so the inverter 66 is effectively cooled by the cooling air.

[0028] The downstream side of the intake duct 48 is inclined diagonally downward and forward as it approaches the top surface of the casing 31. Cooling air flows more easily from the intake port 34 into the gap between the battery 51 and the front wall 41 of the casing 31, and from this front gap, the cooling air is more easily distributed throughout the casing 31 through the gaps between the battery 51 and the side walls 42, 43 of the casing 31. The upstream side of the exhaust duct 49 is inclined diagonally upward and forward as it moves away from the top surface of the casing 31. Cooling air flows from the gap between the inverter 66 and the rear wall 44 of the casing 31 to the exhaust port 36, and the cooling air is more easily introduced into the gap between the inverter 66 and the rear wall 44 of the casing 31.

[0029] The multiple electrical devices are covered from the outside by this housing case 31, thereby improving waterproofing. The electrical devices inside the housing case 31 are not exposed to the wind caused by running, but cooling air is drawn into the housing case 31 by the cooling fan 69. When the cooling air enters the housing case 31 through the intake port 34, it spreads radially above the battery 51. The cooling air directed from the intake port 34 to the rear right cools the DC-DC converter 61, and the cooling air that passes through the opening 56 on the rear surface of the battery holder 52 cools the controller 62. The cooling air that passes through the controller 62 also cools the upper part of the electric motor 63.

[0030] The cooling air flowing forward from the intake port 34 hits the front wall 41 of the housing case 31, and then flows rearward from the front wall 41 along the bottom wall 45 and the left and right side walls 42, 43 of the housing case 31. The cooling air flowing laterally from the intake port 34 hits the side walls 42, 43 of the housing case 31, and then flows rearward along the bottom wall 45 and the side walls 42, 43 of the housing case 31. The battery 51 is entirely cooled by the cooling air that has entered the gaps between the battery 51 and the front wall 41, the side walls 42, 43, and the bottom wall 45 of the housing case 31, and by the cooling air that has been blown from the intake port 34 onto the top surface of the battery 51. The lower part of the electric motor 63 is also cooled by the cooling air that has passed through the gap between the battery 51 and the bottom wall 45.

[0031] The inverter 66 is cooled by the cooling air that has passed through the battery 51. As described above, the gap between the left side wall 43 of the housing case 31 and the battery 51 is wide, and the intake port 34 and the inverter 66 are located on the left side of the housing case 31, so a large amount of cooling air is easily directed from the intake port 34 to the inverter 66. In addition, the cooling air that has passed through the battery 51 hits the rear wall 44 of the housing case 31, and enters the gap between the inverter 66 and the rear wall 44 of the housing case 31. The cooling air then passes through while cooling the inverter 66, and is discharged to the outside through the exhaust port 36 above the inverter 66.

[0032] As described above, according to this embodiment, the battery 51, electric motor 63, and inverter 66 are covered by the housing case 31, thereby preventing water from entering the battery 51, etc., even when the electric vehicle is traveling on a flooded road, etc. Furthermore, even if the battery 51, etc., are covered by the housing case 31, the battery 51, etc. are cooled by the cooling air taken into the housing case 31 from the intake port 34. Therefore, it is possible to achieve both high waterproofing and high cooling performance for the electric unit 30.

[0033] In this embodiment, the cooling fan is provided at the intake port of the storage case, but the cooling fan may be provided at the exhaust port of the storage case.

[0034] In this embodiment, the housing case accommodates electrical devices such as a battery, a DC-DC converter, a controller, an electric motor, and an inverter, but the housing case may accommodate two or more electrical devices that make up the electric drive system. For example, the housing case may accommodate an electric motor and an inverter, or the housing case may accommodate a battery, an electric motor, and an inverter.

[0035] Furthermore, in this embodiment, the electric motor and the inverter are integrated, but the electric motor and the inverter may be formed as separate bodies.

[0036] In this embodiment, the downstream side of the intake duct is inclined forward as it approaches the top surface of the storage case, but the orientation of the downstream side of the intake duct is not particularly limited. For example, the downstream side of the intake duct may face directly downward.

[0037] In this embodiment, the upstream side of the exhaust duct is inclined forward as it moves away from the top surface of the casing, but the orientation of the upstream side of the exhaust duct is not particularly limited. For example, the upstream side of the exhaust duct may face directly upward.

[0038] Furthermore, the electric vehicle is not limited to an ATV, but may be any vehicle that runs on battery power. For example, the electric vehicle may be an electric straddle-type vehicle. A straddle-type vehicle is not limited to all vehicles in which a rider sits astride a seat, but also includes small scooter-type vehicles in which a rider does not sit astride a seat.

[0039] As described above, the electric unit (30) of this embodiment is an electric unit installed in the electric vehicle (1) and includes a plurality of electric devices constituting an electric drive system and a housing case (31) that houses the plurality of electric devices. The housing case has a cooling air intake (34) and an exhaust (36) formed on the top surface thereof, and a cooling fan (69) is provided at the intake or exhaust. With this configuration, the plurality of electric devices are covered by the housing case, thereby preventing water from entering the electric devices even when the electric vehicle travels on flooded roads. Furthermore, even when the plurality of electric devices are covered by the housing case, the electric devices are cooled by the cooling air drawn into the housing case through the intake. This allows the electric unit to have both high waterproofing and high cooling performance.

[0040] In the electric unit of the saddle-ride type vehicle of this embodiment, the plurality of electric devices include an electric motor (63) that drives the electric vehicle, a battery (51) that supplies power to the electric motor, and an inverter (66) that drives the electric motor to rotate. This configuration improves the waterproofing and cooling properties of the electric motor, the battery, and the inverter.

[0041] In the electric unit of the saddle-ride type vehicle of this embodiment, the battery is installed with a gap between it and the front wall (41) and the pair of side walls (42, 43) of the housing case, and the intake port overlaps the battery in a plan view. With this configuration, cooling air is taken into the housing case from above the battery, and the battery is effectively cooled by the cooling air that enters the gap between the battery and the front wall of the housing case and the gap between the battery and the side walls of the housing case.

[0042] In the electric unit of the saddle-ride type vehicle of this embodiment, an intake duct (48) is connected to the intake port, and the downstream side of the intake duct is inclined forward as it approaches the top surface of the housing case. With this configuration, cooling air can easily flow from the intake port into the gap between the battery and the front wall of the housing case, and from this front gap through the gap between the battery and the side wall of the housing case, the cooling air can easily be distributed throughout the entire unit.

[0043] In the electric unit of the saddle-ride type vehicle of this embodiment, the gap between the battery and one side wall of the housing case is larger than the gap between the battery and the other side wall of the housing case, and the inverter is installed closer to one side wall of the housing case. With this configuration, cooling air can easily reach the inverter, which generates a large amount of heat, and the inverter is cooled effectively.

[0044] In the electric unit of the saddle-ride type vehicle of this embodiment, the intake port is formed at a position offset toward one side wall with respect to the center line (L) of the housing case extending in the front-rear direction. With this configuration, the amount of cooling air flowing from the intake port toward the one side wall increases, thereby effectively cooling the inverter.

[0045] In the electric unit for a saddle-ride type vehicle of this embodiment, the inverter is installed with gaps between it and the rear wall (44) and side walls of the housing case. With this configuration, the inverter is effectively cooled by cooling air that enters the gaps between the inverter and the side walls of the housing case and the gaps between the inverter and the rear wall of the housing case.

[0046] In the electric unit of the saddle-ride type vehicle of this embodiment, at least a portion of the exhaust port overlaps with the inverter in a plan view. With this configuration, the cooling air is discharged from above the inverter, which makes it easier for the cooling air to gather at the inverter, thereby effectively cooling the inverter.

[0047] In the electric unit of the saddle-ride type vehicle of this embodiment, an exhaust duct (49) is connected to the exhaust port, and the upstream side of the exhaust duct is inclined forward as it moves away from the top surface of the housing case. With this configuration, cooling air flows from the gap between the inverter and the rear wall of the housing case to the exhaust port, making it easier for the cooling air to enter the gap between the inverter and the rear wall of the housing case.

[0048] Although the present embodiment has been described, other embodiments may be made by combining the above-described embodiments and modifications in whole or in part.

[0049] Furthermore, the technology of the present invention is not limited to the above-described embodiments, and various changes, substitutions, and modifications may be made without departing from the spirit of the technical idea. Furthermore, if the technical idea can be realized in a different way due to technological advances or other derived technologies, it may be implemented using that method. Therefore, the claims cover all embodiments that may fall within the scope of the technical idea. [Explanation of symbols]

[0050] 1: Electric vehicles 30: Electric unit 31: Storage case 34: Intake port 36: Outlet 41: Front wall of storage case 42: Side wall of storage case 43: Side wall of storage case 44: Back wall of storage case 45: Bottom wall of storage case 48: Intake duct 49: Exhaust duct 51: Battery (electrical equipment) 61: DC-DC converter (electrical equipment) 62: Controller (electrical equipment) 63: Electric motor (electrical equipment) 66: Inverter (electrical equipment) 69: Cooling fan

Claims

1. An electric unit installed in an electric vehicle, a plurality of electric devices constituting an electric drive system; a housing case that houses the plurality of electrical devices, the plurality of electric devices include an electric motor that drives the electric vehicle, a battery that supplies power to the electric motor, and an inverter that drives the electric motor to rotate; an intake port and an exhaust port for cooling air are formed on the top surface of the housing case, and a cooling fan is provided at the intake port or the exhaust port; the battery is installed with a gap between it and the front wall and the pair of side walls of the housing case; An electric unit, characterized in that the intake port overlaps the battery in a plan view.

2. an intake duct is connected to the intake port; 2. The electric unit according to claim 1, wherein the downstream side of the intake duct is inclined forward as it approaches the upper surface of the accommodating case.

3. a gap between the battery and one side wall of the housing case is larger than a gap between the battery and the other side wall of the housing case; 3. The electric unit according to claim 2, wherein the inverter is disposed near one side wall of the housing case.

4. 4. The electric unit according to claim 3, wherein the intake port is formed at a position offset toward one side wall with respect to a center line of the accommodating case extending in the front-rear direction.

5. An electric unit installed in an electric vehicle, a plurality of electric devices constituting an electric drive system; a housing case that houses the plurality of electrical devices, the plurality of electric devices include an electric motor that drives the electric vehicle, and an inverter that drives the electric motor to rotate; an intake port and an exhaust port for cooling air are formed on the top surface of the housing case, and a cooling fan is provided at the intake port or the exhaust port; the inverter is installed with a gap between it and the rear wall and the side wall of the housing case, An electric unit, characterized in that at least a portion of the outlet overlaps with the inverter in a plan view.

6. An exhaust duct is connected to the exhaust port, 6. The electric unit according to claim 5, wherein the upstream side of the exhaust duct is inclined forward as it moves away from the upper surface of the accommodating case.

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