Electric vehicle

Abstract

This vehicle (MV) travels using the drive force of rotating electrical machines (31, 32), and comprises front wheels (21), rear wheels (22), and a heat exchanger (50) that exchanges heat with air. In the vehicle (MV), the center of gravity (G) of the heat exchanger (50) is disposed rearwards of the rotational center axis (AX1) of the front wheels (21), and frontwards of the rotational center axis (AX2) of the rear wheels (22).

Description

Cross - reference to related applications

[0001] This application is based on Japanese Patent Application No. 2022 - 071269 filed on April 25, 2022, claims the benefit of its priority, and all the contents of that patent application are incorporated herein by reference.

Technical Field

[0002] The present disclosure relates to an electric vehicle that travels by the driving force of a rotating electric machine.

Background Art

[0003] Vehicles are equipped with a heat exchanger that exchanges heat with air. Examples of such a heat exchanger include a radiator that cools the high - temperature cooling water passing through an internal combustion engine or the like by heat exchange with air. As described in Patent Document 1 below, such a heat exchanger is disposed at a position near the front - end side of the vehicle. Thereby, a large amount of air can be introduced into the vehicle interior and efficiently used for heat exchange.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

[0005] The weight of the heat exchanger is relatively large. In particular, in a vehicle that travels by the driving force of an internal combustion engine, since it is necessary to discharge a large amount of heat generated by the internal combustion engine, the weight of the heat exchanger to be mounted becomes large. When such a heavy object is disposed on the front - side of the vehicle, the center of gravity of the entire vehicle is located closer to the front - side, so there is a possibility that the drivability of the vehicle will deteriorate.

[0006] An object of the present disclosure is to provide an electric vehicle with improved drivability.

[0007] The electric vehicle according to the present disclosure is an electric vehicle that travels by the driving force of a rotating electric machine, and includes a front wheel, a rear wheel, and a heat exchanger that performs heat exchange between the air and the front and rear wheels. In this electric vehicle, the center of gravity of the heat exchanger is arranged at a position behind the rotation center axis of the front wheel and in front of the rotation center axis of the rear wheel.

[0008] Since the electric vehicle does not include an internal combustion engine that discharges a large amount of heat, the performance required for the heat exchanger is relatively small. That is, compared with a vehicle equipped with an internal combustion engine, the necessity of arranging the heat exchanger at a position near the front end is relatively small.

[0009] Therefore, in the electric vehicle having the above configuration, the heat exchanger is arranged so that the center of gravity of the heat exchanger is at a position behind the rotation center axis of the front wheel and in front of the rotation center axis of the rear wheel. As a result, the center of gravity of the entire vehicle can be set at a position further to the rear than before, that is, a position closer to the center of the vehicle in the front-rear direction, so that the drivability of the electric vehicle can be improved.

Brief Description of the Drawings

[0010]

Figure 1

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Modes for Carrying Out the Invention

[0011] Hereinafter, this embodiment will be described with reference to the accompanying drawings. To facilitate understanding of the description, the same reference numerals are attached to the same components in each drawing as much as possible, and redundant descriptions are omitted.

[0012] With reference to FIG. 1, the first embodiment will be described. The vehicle MV according to this embodiment is configured as an electric vehicle that does not include an internal combustion engine and travels by the driving force of the rotary electric machines 31 and 32. As shown in FIG. 1, the vehicle MV includes a body 10, front wheels 21, rear wheels 22, rotary electric machines 31 and 32, a storage battery 40, and a heat exchanger 50. In FIG. 1, the left side is the front side of the vehicle MV, and the right side is the rear side of the vehicle MV.

[0013] The body 10 forms substantially the entire outer shape of the vehicle MV. Inside the body 10, a passenger compartment 16, which is a space where passengers enter, is provided. In FIG. 1, the portion marked with the reference numeral "11" is a tire house that houses the front wheels 21 described later inside. Hereinafter, this tire house will also be referred to as "tire house 11". Similarly, in FIG. 1, the portion marked with the reference numeral "12" is a tire house that houses the rear wheels 22 described later inside. Hereinafter, this tire house will also be referred to as "tire house 12".

[0014] The front wheels 21 are two of the four wheels provided in the vehicle MV and are arranged on the front side. As described above, each front wheel 21 is housed inside the tire house 11. The front wheels 21 are integrally configured with a rotary electric machine 31 that is an in-wheel motor. By the driving force of the rotary electric machine 31, each front wheel 21 rotates around the rotation center axis AX1.

[0015] The rear wheels 22 are two of the four wheels provided on the vehicle MV, and are arranged on the rear side. As described above, each rear wheel 22 is housed inside the tire house 12. The rear wheel 22 is integrally configured with a rotating electric machine 32 which is an in-wheel motor. Due to the driving force of the rotating electric machine 32, each rear wheel 22 rotates around the rotation center axis AX2.

[0016] The rotating electric machines 31 and 32 are rotating electric machines for generating the driving force of the vehicle MV. As described above, both the rotating electric machines 31 and 32 are configured as in-wheel motors. In this embodiment, either one of the rotating electric machines 31 and 32 is provided on each wheel. That is, in the vehicle MV, all four wheels are driving wheels. Instead of such a mode, a configuration in which only either the front wheel 21 or the rear wheel 22 is a driving wheel may be adopted. Also, the number of rotating electric machines provided on the vehicle MV may be four as in this embodiment, but may be less than four.

[0017] The storage battery 40 stores the electric power necessary for driving the rotating electric machines 31 and 32, and is, for example, a lithium-ion battery. The electric power output from the storage battery 40 is converted into alternating current power by an inverter (not shown) and supplied to each of the rotating electric machines 31 and 32. The storage battery 40 is arranged at a position near the bottom 13 in the body 10.

[0018] The heat exchanger 50 is a heat exchanger for performing heat exchange with air. Inside the vehicle MV, water for cooling the storage battery 40, the inverter, etc., that is, cooling water, is circulating. The heat exchanger 50 reduces the temperature of the cooling water by performing heat exchange between the cooling water and air.

[0019] The vehicle MV is provided with an intake pipe 51 and an exhaust pipe 53. The intake pipe 51 is a pipe for taking in air for heat exchange from outside the vehicle MV and introducing the air into the heat exchanger 50. The upstream end of the intake pipe 51 is connected to a position in the hood of the vehicle MV near the windshield. The opening formed at this connection position, that is, the opening formed as the inlet of the air introduced into the heat exchanger 50, is also referred to as the "intake port 52" hereinafter. The intake port 52 opens upward at a position in front of the passenger compartment 16 of the vehicle MV.

[0020] The exhaust pipe 53 is a pipe for discharging the air that has been used for heat exchange in the heat exchanger 50 to the outside of the vehicle MV. The downstream end of the exhaust pipe 53 is connected to the bottom 13 of the vehicle MV. The opening formed at this connection position, that is, the opening formed as the outlet of the air that has passed through the heat exchanger 50, is also referred to as the "exhaust port 54" hereinafter. The exhaust port 54 opens downward at the bottom 13 of the vehicle MV.

[0021] The position of the center of gravity G of the heat exchanger 50 is on the rear side of the rotation center axis AX1 of the front wheel 21 and on the front side of the rotation center axis AX2 of the rear wheel 22. Strictly speaking, the "rotation center axis AX1 of the front wheel 21" mentioned above refers to the rotation center axis AX1 when the steering angle of the front wheel 21 is 0. Similarly, the "rotation center axis AX2 of the rear wheel 22" mentioned above refers to the rotation center axis AX2 when the steering angle of the rear wheel 22 is 0.

[0022] Incidentally, in conventional vehicles, as described in Japanese Patent Application Laid-Open No. 2019-203625 and the like, the heat exchanger was arranged at a position near the front end of the vehicle. This is to introduce a large amount of air into the vehicle during driving and facilitate the supply of the air to the heat exchanger. However, when a heavy object such as a heat exchanger is arranged on the front side of the vehicle, the center of gravity of the entire vehicle becomes a position closer to the front side, so that there may arise a problem that the drivability of the vehicle deteriorates. In particular, in a vehicle driven by the driving force of an internal combustion engine, since it is necessary to discharge a large amount of heat generated by the internal combustion engine, the weight of the heat exchanger to be mounted becomes large, and the above problems are likely to occur.

[0023] Therefore, in the vehicle MV according to the present embodiment, the problem is solved by arranging the center of gravity G of the heat exchanger 50 at the above-described position, that is, a position behind the rotation center axis AX1 of the front wheel 21. Since the overall center of gravity of the vehicle MV can be set at a position behind the conventional position, that is, a position closer to the center of the vehicle MV in the front-rear direction, the drivability of the vehicle MV can be improved.

[0024] Note that it is sufficient that at least the center of gravity G of the heat exchanger 50 is behind the rotation center axis AX1, and a part of the other part of the heat exchanger 50 may enter in front of the rotation center axis AX1. Similarly, it is sufficient that at least the center of gravity G of the heat exchanger 50 is in front of the rotation center axis AX2, and a part of the other part of the heat exchanger 50 may enter behind the rotation center axis AX2.

[0025] The heat exchanger 50 can be arranged at the above position because the vehicle MV is an electric vehicle and does not include an internal combustion engine that discharges a large amount of heat. The heat exchange performance required for the heat exchanger 50 is relatively small, and it is not necessary to introduce a large amount of air into the heat exchanger 50, so the degree of freedom in the position of the heat exchanger 50 is relatively high. Therefore, in the present embodiment, importance is attached to the drivability of the vehicle MV, and the heat exchanger 50 is arranged behind the rotation center axis AX1.

[0026] Furthermore, in the present embodiment, by disposing the heat exchanger 50 at a position more rearward than in the conventional case, the cooling water pipe connecting between the storage battery 40 to be cooled and the heat exchanger 50 is shortened. As a result, there is also an advantage that a water pump (not shown) for circulating the cooling water can be miniaturized.

[0027] In accordance with the arrangement of the heat exchanger 50 at the above-described position, in the present embodiment, the position of the air inlet 52, which is the air inlet, is also changed from the conventional position. In conventional vehicles, it has been common to form the air inlet at the front-end portion 14 (front grille) of the vehicle. Also, in order to easily introduce a large amount of air during traveling, the shape of the end portion 14 needs to be a shape having a surface substantially perpendicular to the front-rear direction.

[0028] However, in the vehicle MV which is an electric vehicle, since the heat exchange performance required for the heat exchanger 50 is relatively small, it is not subject to the restriction on the position of the air inlet. Therefore, in the present embodiment, as described above, the air inlet 52 is formed at a position other than the end portion 14. Since there is no longer the conventional restriction on the shape of the end portion 14, the shape of the end portion 14 can be freely set. As a result, it becomes possible to improve the Cd value of the vehicle MV and enhance the fuel efficiency, or to enhance the design quality of the vehicle MV.

[0029] In the present embodiment, the air inlet 52 opens upward at a position that is on the front side of the passenger compartment 16 of the vehicle MV and in the vicinity of the windshield. At such a position, since the traveling wind hits the windshield, the air pressure is relatively high. Therefore, it is possible to introduce a relatively large amount of air from the air inlet 52 formed at the position.

[0030] Also, as described above, in the present embodiment, the discharge port 54 is formed in the bottom portion 13 of the vehicle MV. Between the bottom portion 13 of the vehicle MV and the road surface, the running wind can easily flow from the front side to the rear side. Due to the influence of the running wind, a negative pressure is generated directly below the discharge port 54, so the flow of air from the heat exchanger 50 toward the discharge port 54 is promoted. That is, in the present embodiment, by forming the discharge port 54 at the above position, it is possible to further increase the flow rate of the air passing through the heat exchanger 50.

[0031] The second embodiment will be described with reference to FIG. 2. Hereinafter, the points different from the first embodiment will be mainly described, and the description of the points common to the first embodiment will be omitted as appropriate.

[0032] In the present embodiment, it is different from the first embodiment in the position where the discharge port 54 is formed. As shown in FIG. 2, the discharge port 54 of the present embodiment is formed on the outer surface of the vehicle MV. The air that has passed through the heat exchanger 50 is discharged from the discharge port 54 toward only one or both of the left and right sides of the vehicle MV.

[0033] In such a configuration, there is no need to route the discharge pipe 53 to the bottom portion 13 of the vehicle MV. The size of the battery 40 disposed at the bottom portion 13 can be increased without worrying about interference with the discharge pipe 53, so the cruising range of the vehicle MV can be extended.

[0034] The third embodiment will be described with reference to FIG. 3. Hereinafter, the points different from the first embodiment will be mainly described, and the description of the points common to the first embodiment will be omitted as appropriate.

[0035] Also in the present embodiment, it is different from the first embodiment in the position where the discharge port 54 is formed. As shown in FIG. 3, the discharge port 54 of the present embodiment is formed on the inner surface of the tire house 11 of the vehicle MV. The air that has passed through the heat exchanger 50 is discharged from the discharge port 54 toward the front wheel 21.

[0036] Even in such a configuration, the same effects as those described in the second embodiment can be achieved.

[0037] The fourth embodiment will be described with reference to FIG. 4. Hereinafter, the points different from the first embodiment will be mainly described, and the description of the points common to the first embodiment will be omitted as appropriate.

[0038] Also in this embodiment, it is different from the first embodiment in the position where the outlet 54 is formed. As shown in FIG. 4, the outlet 54 of this embodiment is formed on the inner surface of the passenger compartment 16 in the vehicle MV. The air that has passed through the heat exchanger 50 is discharged from the outlet 54 toward the inside of the passenger compartment 16.

[0039] In such a configuration, the passenger compartment 16 can be heated using the air that has passed through the heat exchanger 50 and has had its temperature increased. Thereby, the electric power consumed for heating can be reduced.

[0040] The fifth embodiment will be described with reference to FIG. 5. Hereinafter, the points different from the first embodiment will be mainly described, and the description of the points common to the first embodiment will be omitted as appropriate.

[0041] In this embodiment, the arrangement of the heat exchanger 50 and the inlet pipe 51 and the outlet pipe 53 connected thereto is different from that of the first embodiment. As shown in FIG. 5, the heat exchanger 50 of this embodiment is arranged at a position near the rear wheel 22. However, also in this embodiment, similar to the first embodiment, the position of the center of gravity G of the heat exchanger 50 is on the rear side of the rotation center axis AX1 of the front wheel 21 and on the front side of the rotation center axis AX2 of the rear wheel 22. In addition, when viewed along the left - right direction of the vehicle MV as shown in FIG. 5, a part of the heat exchanger 50 may be arranged at a position overlapping the rear wheel 22.

[0042] The inlet 52 of this embodiment opens toward the inside of the passenger compartment 16. Also, the outlet 54 of this embodiment opens downward at the bottom 13 of the vehicle MV, similar to the first embodiment.

[0043] In such a configuration, the overall center of gravity of the vehicle MV can be positioned behind the center of the vehicle MV in the front-rear direction. For example, when the vehicle MV is configured as a rear-wheel drive vehicle, since the center of gravity is close to the drive wheels, the drivability of the vehicle MV can be improved.

[0044] The sixth embodiment will be described with reference to FIG. 6. Hereinafter, the points different from the above-described fifth embodiment will be mainly described, and the description of the points common to the fifth embodiment will be omitted as appropriate.

[0045] In the present embodiment, it is different from the fifth embodiment (FIG. 5) in the position where the discharge port 54 is formed. As shown in FIG. 6, the discharge port 54 of the present embodiment is formed on the inner surface of the tire house 12 of the vehicle MV. The air that has passed through the heat exchanger 50 is discharged from the discharge port 54 toward the rear wheel 22. Even with such a configuration, the same effects as those described in the fifth embodiment can be achieved.

[0046] The seventh embodiment will be described with reference to FIG. 7. Hereinafter, the points different from the above-described fifth embodiment will be mainly described, and the description of the points common to the fifth embodiment will be omitted as appropriate.

[0047] Also in the present embodiment, it is different from the fifth embodiment (FIG. 5) in the position where the discharge port 54 is formed. As shown in FIG. 7, the discharge port 54 of the present embodiment is formed at the rear end portion 15 of the vehicle MV and opens toward the rear side. Even with such a configuration, the same effects as those described in the fifth embodiment can be achieved. Further, similar to the second embodiment (FIG. 2), since it is not necessary to route the discharge pipe 53 to the bottom 13 of the vehicle MV, the battery 40 disposed at the bottom 13 can be enlarged without worrying about interference with the discharge pipe 53. Note that the discharge port 54 may be formed at a position different from the end portion 15 as long as it is formed toward the rear side of the vehicle MV.

[0048] The above-described embodiments have been explained with reference to specific examples. However, the present disclosure is not limited to these specific examples. As long as those obtained by appropriately making design changes by those skilled in the art to these specific examples have the features of the present disclosure, they are included in the scope of the present disclosure. Each element included in each of the above-described specific examples, as well as its arrangement, conditions, shape, etc., are not limited to those illustrated and can be changed as appropriate. Each element included in each of the above-described specific examples can be appropriately combined as long as no technical contradiction occurs.

Claims

1. An electric vehicle (MV) that travels by the driving force of a rotating electric machine (31, 32), a front wheel (21), a rear wheel (22), and a heat exchanger (50) that performs heat exchange between air and water, wherein the center of gravity (G) of the heat exchanger is disposed at a position behind the rotation center axis (AX1) of the front wheel and in front of the rotation center axis (AX2) of the rear wheel, an inlet (52), which is an inlet of air introduced into the heat exchanger, is formed at a position other than the front end (14) of the electric vehicle, and the inlet opens upward at a position in front of the passenger compartment (16) of the electric vehicle and near the windshield of the electric vehicle. An electric vehicle.

2. The electric vehicle according to claim 1, wherein an outlet, which is an outlet of the air that has passed through the heat exchanger, is formed on an outer surface of the electric vehicle.

3. The electric vehicle according to claim 1, wherein an outlet, which is an outlet of the air that has passed through the heat exchanger, is formed on an inner surface of the tire houses (11, 12) of the electric vehicle.

4. The electric vehicle according to claim 1, wherein an outlet, which is an outlet of the air that has passed through the heat exchanger, opens toward the rear side of the electric vehicle.

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