Driving airflow control device

Abstract

The present invention provides a driving airflow control device that can reduce aerodynamic drag during vehicle travel. [Solution] The airflow control device 20 comprises an airflow passage 21, a front opening 22, a first rear opening 23, and a second rear opening 24. The airflow passage 21 is formed from the portion inside the vehicle width direction of the rear tire 14 to the rear side of the rear tire 14. The front opening 22 is formed on the front end side of the airflow passage 21. The first rear opening 23 is formed on the rear end side of the airflow passage 21 and opens toward the rear. The second rear opening 24 is formed on the rear end side of the airflow passage 21 and opens toward the downward.

Description

TECHNICAL FIELD

[0001] The present invention relates to a traveling wind control device that controls a blowing path of traveling wind in a vehicle body.

BACKGROUND ART

[0002] As a vehicle travels, traveling wind passes around the vehicle body. Control of traveling wind is important when examining aerodynamic characteristics and steering performance. Inventions that improve aerodynamic performance and the like by controlling traveling wind are described in the following patent documents.

[0003] Patent Document 1 is provided with a vehicle lower airflow control device. The vehicle lower airflow control device has an undercover opening, a bumper opening located on the vehicle rear side relative to the undercover opening and on the vehicle upper side, an air flow path that communicates the undercover opening and the bumper cover opening, and an opening / closing plate. Thereby, the airflow flowing below the vehicle during vehicle travel can be guided to the upper side of the vehicle.

[0004] Patent Document 2 describes an engine cooling device for a rear-engine vehicle. Specifically, this engine cooling device has an inlet, an outlet, a duct forming an air flow path between the inlet and the outlet, a radiator provided at an intermediate portion of the duct, and a valve member for opening and closing the rearwardly opened outlet. Thereby, the cooling air that has passed through the radiator can be discharged rearward during normal traveling, and can be discharged exclusively downward during low-speed traveling or when the vehicle is stopped.

[0005] Patent Document 3 describes a vehicle aerodynamic performance improvement device. Specifically, the aerodynamic performance improvement device has an air duct equipped with an air inlet and an air outlet. The air inlet is provided at the front of the vehicle, facing the region where the air pressure is higher than atmospheric pressure when the vehicle is traveling forward. The air outlet is provided at the rear of the vehicle body, inclined upward and to the rear. When the vehicle is traveling at high speed, the differential pressure between the air inlet and the air outlet causes the air taken into the air duct through the air inlet to be ejected to the area through the air outlet. In addition, the separation region of the airflow generated at the area and the vortex generated at the rear of the vehicle are reduced, thereby improving the aerodynamic performance of the vehicle. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2017-100586 [Patent Document 2] Japanese Patent Publication No. 2003-276454 [Patent Document 3] Japanese Patent Publication No. 2005-170304 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, the inventions described in the aforementioned patent documents had room for improvement in terms of further enhancing aerodynamic characteristics during vehicle travel.

[0008] Specifically, when a vehicle is moving, airflow is generated on the underside of the vehicle. This airflow is sometimes referred to as underbody airflow. On the underside of the vehicle, near the center in the vehicle's width direction, there are no obstructions to block the airflow, so the airflow flows at high speed. On the other hand, on the underside of the vehicle, behind the rear tires, the rear tires act as an obstruction to the airflow, so the airflow flows at a relatively low speed. As a result, at the rear of the vehicle, the airflow blown from the underside of the vehicle towards the rear is swirled up and forms a vortex, which pulls the vehicle backward and increases aerodynamic drag.

[0009] This invention has been made in view of these problems, and the object of this invention is to provide a driving airflow control device that can reduce aerodynamic resistance when a vehicle is moving. [Means for solving the problem]

[0010] An embodiment of the present invention is a driving airflow control device that controls the flow of air under a moving vehicle, and comprises a driving air passage, a front opening, a first rear opening, and a second rear opening, wherein the driving air passage is formed from the inside in the vehicle width direction of the rear tire to the rear side of the rear tire, the front opening is formed at the front end of the driving air passage, the first rear opening is formed at the rear end of the driving air passage and opens toward the rear, and the second rear opening is formed at the rear end of the driving air passage and opens toward the downward. [Effects of the Invention]

[0011] According to the airflow control device according to an embodiment of the present invention, when the vehicle is moving, airflow is blown out from the first rear opening toward the rear, thereby improving the airflow velocity behind the rear tires and improving aerodynamic performance. Furthermore, when the vehicle is moving, airflow is blown out from the second rear opening toward the downward, which suppresses the kicking up of dust by the rotating rear tires and prevents dust from adhering to the rear window. [Brief explanation of the drawing]

[0012] [Figure 1] It is a side view showing a vehicle provided with a traveling wind control device according to an embodiment of the present invention. [Figure 2] It is a bottom view partially showing the lower portion of a vehicle provided with the traveling wind control device according to the embodiment of the present invention. [Figure 3] It is a cross-sectional view partially showing a vehicle provided with the traveling wind control device according to the embodiment of the present invention. [Figure 4] It is a cross-sectional view partially showing a vehicle provided with the traveling wind control device according to the embodiment of the present invention. [Figure 5] It is a block diagram showing the connection configuration of the traveling wind control device according to the embodiment of the present invention. [Figure 6] It is a flowchart showing the operation of the traveling wind control device according to the embodiment of the present invention. [Figure 7A] It is a cross-sectional view showing the first operation mode of the traveling wind control device according to the embodiment of the present invention. [Figure 7B] It is a bottom view showing the first operation mode of the traveling wind control device according to the embodiment of the present invention. [Figure 8A] It is a cross-sectional view showing the second operation mode of the traveling wind control device according to the embodiment of the present invention. [Figure 8B] It is a bottom view showing the second operation mode of the traveling wind control device according to the embodiment of the present invention. [Figure 9A] It is a cross-sectional view showing another operation mode of the traveling wind control device according to the embodiment of the present invention. [Figure 9B] It is a bottom view showing another operation mode of the traveling wind control device according to the embodiment of the present invention. [Figure 10] It is a graph showing the characteristics of the traveling wind control device according to the embodiment of the present invention. [Modes for Carrying Out the Invention]

[0013] Hereinafter, a traveling wind control device 20 and a vehicle 10 according to an embodiment of the present invention will be described in detail based on the drawings. In the following description, front-rear, up-down, and left-right directions are used, where left and right refer to the left and right directions when the vehicle 10 is viewed from the rear. Furthermore, in the following description, identical members are in principle assigned identical reference numerals, and repeated descriptions are omitted.

[0014] FIG. 1 is a side view showing the vehicle 10 provided with the traveling wind control device 20.

[0015] The vehicle 10 is, for example, an engine vehicle, a BEV (Battery Electric Vehicle), a HEV (Hybrid Electric Vehicle), a PHEV (Plug-in Hybrid Electric Vehicle), or the like.

[0016] The vehicle 10 includes a vehicle body 11. The vehicle body 11 is provided with front tires 13 and rear tires 14. The front tires 13 and the rear tires 14 are disposed inside tire hoods 17. By providing the rear tires 14, vortices due to traveling wind are formed behind the rear tires 14 when the vehicle 10 is traveling, which may affect aerodynamic performance. In the present embodiment, by providing the traveling wind control device 20 described later, the formation of the vortices is suppressed to improve aerodynamic performance.

[0017] The vehicle body 11 includes a vehicle lower portion 12. The vehicle lower portion 12 is a part that forms the lower surface of the vehicle body 11 and the vicinity thereof. The lower surface of the vehicle lower portion 12 has a shape in which the formation of protruding portions is suppressed in order to reduce air resistance.

[0018] The traveling wind control device 20 is disposed at the rear portion of the vehicle lower portion 12, and is a device for enhancing the aerodynamic performance of the vehicle 10. The traveling wind control device 20 is disposed on the rear side of the rear tires 14. Specifically, the front end portion of the traveling wind control device 20 is disposed further forward than the rear end portions of the rear tires 14. In addition, the rear end portion of the traveling wind control device 20 is disposed further rearward than the rear end portions of the rear tires 14.

[0019] Figure 2 is a partial bottom view showing the lower part 12 of a vehicle 10 equipped with a running airflow control device 20. Here, the structure of the running airflow control device 20 located on the right side of the rear of the vehicle body 11 is shown. In addition, a running airflow control device 20 having a configuration similar to that shown in Figure 2 is also located on the left side of the rear of the vehicle body 11.

[0020] The airflow control device 20 is a device that controls the airflow under a moving vehicle 10. The airflow control device 20 mainly comprises an airflow passage 21, a front opening 22, a first rear opening 23, and a second rear opening 24. Furthermore, the airflow control device 20 comprises a vehicle speed sensor 15 (described later), a first opening / closing unit 25, a second opening / closing unit 26, and a calculation control unit 16 (described later).

[0021] The air duct 21 is a curved air tunnel formed from the inside of the vehicle width direction beyond the rear tire 14 to the rear of the rear tire 14. Specifically, the air duct 21 can be made of a plate-shaped synthetic resin sheet. The front end of the air duct 21 is positioned inside the rear tire 14 in the vehicle width direction and forward of the rear end of the rear tire 14 in the longitudinal direction. The rear end of the air duct 21 is positioned behind the rear tire 14. Therefore, the air duct 21 has a shape that curves to the right as it approaches the rear.

[0022] The front opening 22 is an opening formed on the front end side of the airflow passage 21. The front opening 22 is an opening that connects the front end of the airflow passage 21 to the outside of the vehicle. The front opening 22 is roughly rectangular in shape. As will be described later, when the vehicle 10 is traveling, air is introduced into the airflow passage 21 from the front opening 22.

[0023] The first rear opening 23 is formed on the rear end side of the airflow passage 21 and opens towards the rear. The first rear opening 23 is an opening that connects the rear end of the airflow passage 21 to the outside of the vehicle. As will be described later, when the vehicle 10 is moving, airflow is blown out from the first rear opening 23 toward the rear. When the vehicle is moving, the airflow velocity of the airflow on the rear side of the rear tires 14 is improved, thereby improving aerodynamic performance. A first opening / closing section 25 is installed in the first rear opening 23. The first opening / closing section 25 will be described later with reference to Figure 4.

[0024] The second rear opening 24 is formed on the rear end side of the airflow passage 21 and opens downward. The first rear opening 23 is an opening that connects the rear end of the airflow passage 21 to the outside of the vehicle. When the vehicle 10 is moving, air is blown out downward from the second rear opening 24. When the vehicle is moving, the air blown out downward from the second rear opening 24 suppresses the stirring up of dust by the rotating rear tires 14 and prevents dust from adhering to the rear glass. A second opening / closing section 26 is installed in the second rear opening 24. The second opening / closing section 26 will be described later with reference to Figure 4.

[0025] Figure 3 is a partial cross-sectional view of a vehicle 10 equipped with a running airflow control device 20. Figure 3 is a cross-sectional view along the AA cross-section line in Figure 2. The AA cross-section includes the longitudinal and vertical directions. In Figure 3 and subsequent figures, the running airflow generated when the vehicle 10 is running is indicated by a dashed line.

[0026] As mentioned above, a front opening 22 is formed at the front end of the airflow passage 21. The front opening 22 is a part that opens downwards. Here, the front opening 22 is always in an open state. However, an opening / closing mechanism can also be installed in the front opening 22 to open and close the front opening 22. This opening / closing mechanism can have the same configuration as the second opening / closing mechanism 26, which will be described later.

[0027] When the vehicle 10 is moving, a high-speed airflow is generated between the underside of the vehicle 12 and the ground. A portion of this airflow is introduced into the airflow duct 21 through the front opening 22.

[0028] Figure 4 is a partially cross-sectional view of a vehicle 10 equipped with a running airflow control device 20. Figure 4 is a cross-sectional view along the BB cross-section line of Figure 2. The BB cross-section is a cross-section that includes the longitudinal and vertical directions.

[0029] A first opening / closing section 25 and a second opening / closing section 26 are installed at the rear end of the airflow passage 21.

[0030] The first opening / closing section 25 is configured to open or close the first rear opening 23. The mechanism for opening and closing the first opening / closing section 25 can be a rotary type or a sliding type. In this case, a rotary damper is used as the first opening / closing section 25. Specifically, a rotating shaft is provided in the middle of the first opening / closing section 25, and the first opening / closing section 25 can rotate around this rotating shaft as the center of rotation. The rotation of the first opening / closing section 25 is driven by an actuator such as a motor. The first rear opening 23 is an opening that opens toward the rear. Therefore, when the first opening / closing section 25 is in a vertical position, the first opening / closing section 25 closes the first rear opening 23, and no airflow is blown out toward the rear from the first rear opening 23. On the other hand, when the first opening / closing section 25 rotates to a horizontal position, the first opening / closing section 25 opens the first rear opening 23, and airflow is blown out toward the rear from the first rear opening 23.

[0031] The second opening / closing section 26 is configured to open or close the second rear opening 24. The mechanism for opening and closing the second opening / closing section 26 can be a rotary type or a sliding type, similar to the first opening / closing section 25. In this case, a rotary damper is used for the second opening / closing section 26. Specifically, a rotating shaft is provided in the middle of the second opening / closing section 26, and the second opening / closing section 26 can rotate around this rotating shaft as the center of rotation. The rotation of the second opening / closing section 26 is driven by an actuator such as a motor. The second rear opening 24 is an opening that opens downwards. Therefore, when the second opening / closing section 26 is horizontal, the second opening / closing section 26 closes the second rear opening 24, and no airflow is blown downwards from the second rear opening 24. On the other hand, when the second opening / closing section 26 rotates to a vertical position, the second opening / closing section 26 opens the second rear opening 24, and airflow is blown downwards from the second rear opening 24.

[0032] The first rear opening 23 is positioned further rear than the second rear opening 24. The first rear opening 23 also opens towards the rear. As shown in Figure 2, the first rear opening 23 has a substantially rectangular shape with a longitudinal direction along the vehicle width. The first rear opening 23 is formed behind the rear tire 14. This configuration allows for more effective discharge of high-speed airflow towards the rear from the first rear opening 23 when the vehicle 10 is in motion. The second rear opening 24 is positioned close to the rear tire 14. Therefore, the upward movement of dust particles kicked up by the rotation of the rear tire 14 can be effectively suppressed by the airflow blown downward from the second rear opening 24.

[0033] The second rear opening 24 is positioned below the first rear opening 23. The second rear opening 24 also opens downwards. As shown in Figure 2, the second rear opening 24 has a substantially rectangular shape with its longitudinal direction along the vehicle width. Referring to Figure 2, the left end of the second rear opening 24 may be positioned to the left of the left end of the rear tire 14. Furthermore, the right end of the second rear opening 24 may be positioned to the left of the right end of the rear tire 14. By doing so, as will be described later, the upward movement of dust that is kicked up by the rotation of the rear tire 14 can be effectively suppressed by the airflow blown out from the second rear opening 24.

[0034] Figure 5 is a block diagram showing the connection configuration of the airflow control device 20. The airflow control device 20 includes a calculation control unit 16, a vehicle speed sensor 15, a first switching unit 25, and a second switching unit 26. The vehicle speed sensor 15 is connected to the input terminal of the calculation control unit 16. The first switching unit 25 and the second switching unit 26 are connected to the output terminal of the calculation control unit 16.

[0035] The vehicle speed sensor 15 is configured to detect the speed at which the vehicle 10 is traveling. The vehicle speed sensor 15 transmits information indicating the speed of the vehicle 10 to the calculation control unit 16.

[0036] The first opening / closing unit 25 is a device that appropriately opens or closes the aforementioned first rear opening 23. As described above, the first opening / closing unit 25 opens and closes the first rear opening 23 based on instruction signals provided by the calculation control unit 16.

[0037] The second opening / closing unit 26 is a device that appropriately opens or closes the second rear opening 24 mentioned above. As described above, the second opening / closing unit 26 opens and closes the second rear opening 24 based on instruction signals provided by the calculation control unit 16.

[0038] The arithmetic control unit 16 consists of semiconductor elements such as a CPU (Central Processing Unit). The arithmetic control unit 16 may also include semiconductor memory devices such as RAM (Random Access Memory) and ROM (Read Only Memory) as storage units. Such storage units store programs, parameters, etc. Based on the programs, parameters, etc. read from the storage units, the arithmetic control unit 16 executes the functions and methods described later.

[0039] For example, the calculation control unit 16 changes the opening degree of the first opening / closing section 25 or the second opening / closing section 26 according to the travel speed. Furthermore, in the first operation mode described later, the calculation control unit 16 decreases the opening degree of the first opening / closing section 25 as the travel speed increases. Moreover, the calculation control unit 16 executes the first operation mode if the travel speed exceeds a predetermined threshold speed, and executes the second operation mode described later if the travel speed is below the threshold speed. In addition, in the first operation mode, the calculation control unit 16 opens the first rear opening 23 using the first opening / closing section 25 and closes the second rear opening 24 using the second opening / closing section 26. Furthermore, in the second operation mode, the calculation control unit 16 closes the first rear opening 23 using the first opening / closing section 25 and opens the second rear opening 24 using the second opening / closing section 26. These functions of the calculation control unit 16 will be described later with reference to Figure 6, etc.

[0040] Figure 6 is a flowchart showing the operation of the airflow control device 20. Based on Figure 6, and referring to the figures mentioned above, the operation of the airflow control device 20 will be explained below.

[0041] In step S10, the calculation control unit 16 drives the vehicle 10. Specifically, referring to Figure 1, based on instructions from the occupants and the calculation control unit 16, the driving force of the engine or motor mounted on the vehicle body 11 rotates the front tires 13 and rear tires 14. This causes the vehicle 10 to move. As the vehicle 10 moves, airflow is generated. The airflow flows along the surface of the vehicle body 11 toward the rear. A portion of the airflow flows between the underside of the vehicle 12 and the ground.

[0042] In step S11, the calculation control unit 16 determines whether the driving speed of the vehicle 10 detected by the vehicle speed sensor 15 exceeds a predetermined threshold speed.

[0043] If the answer in step S11 is YES, that is, if the driving speed exceeds the threshold speed, the calculation control unit 16 determines that the vehicle 10 is driving at high speed and proceeds to step S12.

[0044] If the answer in step S11 is NO, that is, if the driving speed is below the threshold speed, the calculation control unit 16 determines that the vehicle 10 is driving at a low speed, and the calculation control unit 16 proceeds to step S13.

[0045] In step S12, the calculation control unit 16 executes the first operating mode during high-speed driving. Step S12 will be described with reference to Figures 7A and 7B. Figure 7A is a cross-sectional view showing the first operating mode of the driving airflow control device 20. Figure 7B is a bottom view showing the first operating mode of the driving airflow control device 20.

[0046] Referring to Figure 7A, in the first operating mode, the arithmetic control unit 16 opens the first rear opening 23 using the first opening / closing unit 25 and closes the second rear opening 24 using the second opening / closing unit 26. Here, the front opening 22 shown in Figure 7B is in the open state.

[0047] When the vehicle 10 is traveling at high speed in this state, as shown in Figure 7B, the airflow is introduced into the air duct 21 from the front opening 22. The airflow introduced into the air duct 21 is blown towards the rear right along the curved shape of the air duct 21. Subsequently, the airflow is blown out towards the rear from the first rear opening 23. As shown in Figure 7A, the first opening / closing section 25 is in a horizontal position, which opens the first rear opening 23. Therefore, the airflow is blown out towards the rear at high speed from the first rear opening 23. At this time, the second rear opening 24 is in a closed state.

[0048] By doing so, the airflow velocity behind the rear tire 14 can be made approximately equal to the airflow velocity of the airflow flowing from the middle of the vehicle's lower section 12 toward the rear. Therefore, the formation of vortices caused by the airflow behind the vehicle 10 is suppressed. As a result, the aerodynamic performance of the vehicle 10 when it is traveling can be improved.

[0049] In step S13, the calculation control unit 16 executes a second operating mode during low-speed driving. Here, low-speed driving includes driving at a low speed on a paved road and driving at a low speed on an unpaved road. Step S13 will be described with reference to Figures 8A and 8B. Figure 8A is a cross-sectional view showing the second operating mode of the driving airflow control device 20. Figure 8B is a bottom view showing the second operating mode of the driving airflow control device 20.

[0050] Referring to Figure 8A, in step S13, the calculation control unit 16 closes the first rear opening 23 by making the first opening / closing unit 25 vertical. On the other hand, the calculation control unit 16 opens the second rear opening 24 by making the second opening / closing unit 26 vertical.

[0051] In this state, when the vehicle 10 is traveling at a low speed, as shown in Figure 8B, the airflow is introduced from the front opening 22 into the airflow duct 21. The airflow introduced into the airflow duct 21 is blown towards the rear right along the curved shape of the airflow duct 21. Subsequently, the airflow is blown downward from the second rear opening 24. As shown in Figure 8A, when the airflow is blown downward from the second rear opening 24, even if dust is kicked up by the rotation of the rear tires 14, the airflow will suppress the dust. Therefore, the adhesion of dust to the rear window of the vehicle 10 is suppressed. At this time, the first rear opening 23 is closed.

[0052] In step S14, the vehicle 10 stops based on the instructions of the arithmetic control unit 16.

[0053] Figure 9A is a cross-sectional view showing another operating mode of the airflow control device 20. Figure 9B is a bottom view showing another operating mode of the airflow control device 20. In this view, both the first rear opening 23 and the second rear opening 24 are open.

[0054] Referring to Figure 9A, here, based on instructions from the calculation control unit 16, the first opening / closing section 25 becomes horizontal, opening the first rear opening 23, and the second opening / closing section 26 becomes vertical, opening the second rear opening 24.

[0055] Referring to Figure 9B, when the vehicle 10 is in motion, airflow is drawn in through the front opening 22 into the airflow duct 21. Inside the airflow duct 21, the airflow is blown towards the rear right before being released outside the vehicle through the first rear opening 23 and the second rear opening 24. Specifically, referring to Figure 9A, airflow is released from the first rear opening 23 towards the rear, and the airflow is straightened at the rear of the vehicle body 11. Furthermore, airflow is released downward from the second rear opening 24, which helps to suppress dust kicked up by the rear tires 14.

[0056] Figure 10 is a graph showing the characteristics of the airflow control device 20. In this graph, the horizontal axis represents the vehicle speed of the vehicle 10, and the vertical axis represents the opening dimensions of each opening, i.e., the degree of opening.

[0057] The degree to which the first rear opening 23 is opened can be adjusted according to the vehicle speed 10. For example, referring to Figure 9A, as the vehicle speed 10 increases, the opening degree of the first rear opening 23 can be increased. Here, the opening degree of the first rear opening 23 is increased by bringing the first opening / closing part 25 closer to horizontal. Conversely, as the vehicle speed 10 increases, the opening degree of the first rear opening 23 can also be decreased. Here, the opening degree of the first rear opening 23 is decreased by bringing the first opening / closing part 25 closer to vertical. In Figure 10, until the vehicle speed 10 reaches a predetermined speed, the opening degree of the first rear opening 23 is increased in accordance with the vehicle speed 10. On the other hand, once the vehicle speed 10 exceeds the predetermined speed, the opening degree of the first rear opening 23 is decreased in accordance with the vehicle speed 10.

[0058] Similarly, the degree to which the second rear opening 24 is opened can be adjusted according to the vehicle speed 10, etc. For example, referring to Figure 9A, as the vehicle speed 10 increases, the opening degree of the second rear opening 24 can be increased. Here, the opening degree of the second rear opening 24 is increased by making the second opening / closing part 26 closer to vertical. Conversely, as the vehicle speed 10 increases, the opening degree of the second rear opening 24 can also be decreased. Here, the opening degree of the second rear opening 24 is decreased by making the second opening / closing part 26 closer to horizontal. In Figure 10, the opening degree of the second rear opening 24 is decreased as the vehicle speed 10 increases.

[0059] By controlling the opening of the first rear opening 23 and the second rear opening 24 as shown in Figure 10, the underbody airflow, which is the airflow below the lower part of the vehicle 12, can be effectively controlled when the vehicle 10 is traveling. Therefore, the aerodynamic characteristics of the vehicle 10 when it is traveling can be improved.

[0060] The above is a description of the functions of the airflow control device 20.

[0061] Referring to Figure 2, the size of each opening and its aerodynamic performance will be explained. As mentioned above, the airflow control device 20 has a front opening 22, a first rear opening 23, and a second rear opening 24. The front opening 22 is an opening that takes in airflow from the outside into the airflow passage 21. The first rear opening 23 and the second rear opening 24 are openings that release airflow from the airflow passage 21 to the outside of the vehicle.

[0062] Here, the size of the front opening 22 is made larger than the first rear opening 23 and the second rear opening 24. By doing so, the airflow released to the outside of the vehicle from the first rear opening 23 and the second rear opening 24 is accelerated, the flow velocity of the underbody airflow flowing below the lower part of the vehicle 12 is controlled, and the aerodynamic performance of the vehicle 10 is improved.

[0063] Furthermore, by taking in a portion of the airflow from the front opening 22 into the airflow duct 21, the airflow velocity in the middle section of the vehicle width direction below the lower part of the vehicle 12 is reduced. On the other hand, behind the rear tires 14, although the rear tires 14 act as an obstacle, the airflow velocity can be increased by releasing high-speed airflow towards the rear from the first rear opening 23. Therefore, the airflow velocity at the rear of the vehicle body 11 can be equalized in the vehicle width direction. Thus, when the vehicle 10 is moving, the turbulence of airflow behind the rear tires 14 can be reduced, and aerodynamic performance can be improved.

[0064] The technical concepts that can be understood from the above-mentioned embodiment, along with their effects, are described below.

[0065] An embodiment of the present invention is a driving airflow control device that controls the flow of air under a moving vehicle, and comprises a driving air passage, a front opening, a first rear opening, and a second rear opening, wherein the driving air passage is formed from the inside in the vehicle width direction of the rear tire to the rear side of the rear tire, the front opening is formed at the front end of the driving air passage, the first rear opening is formed at the rear end of the driving air passage and opens toward the rear, and the second rear opening is formed at the rear end of the driving air passage and opens toward the downward. According to the driving airflow control device of the present invention, when the vehicle is moving, the airflow velocity on the rear side of the rear tire is improved by blowing air toward the rear from the first rear opening, thereby improving aerodynamic performance. Furthermore, when the vehicle is moving, the airflow is blown toward the downward from the second rear opening, which suppresses the stirring up of dust by the rotating rear tire and prevents dust from adhering to the rear window.

[0066] Furthermore, the driving airflow control device according to an embodiment of the present invention further comprises a vehicle speed sensor, a first opening / closing unit, a second opening / closing unit, and a calculation control unit, wherein the vehicle speed sensor detects the driving speed at which the vehicle is traveling, the first opening / closing unit is configured to open or close the first rear opening, the second opening / closing unit is configured to open or close the second rear opening, and the calculation control unit executes a first operation mode when the driving speed exceeds a predetermined threshold speed, and executes a second operation mode when the driving speed is less than or equal to the threshold speed, wherein in the first operation mode, the first opening / closing unit opens the first rear opening and the second opening / closing unit closes the second rear opening, and in the second operation mode, the first opening / closing unit closes the first rear opening and the second opening / closing unit opens the second rear opening. According to the driving airflow control device of the present invention, the first operation mode is executed when the vehicle is traveling at high speed, and the second operation mode is executed when the vehicle is traveling at low speed. In the first operating mode during high-speed driving, airflow is blown out from the first rear opening towards the rear, improving the airflow velocity behind the rear tires and enhancing aerodynamic performance. On the other hand, in the second operating mode during low-speed driving, airflow is blown out from the second rear opening towards the rear, suppressing the kickup of dust by the rotating rear tires and preventing dust from adhering to the rear window.

[0067] Furthermore, in the driving airflow control device according to an embodiment of the present invention, the calculation control unit is characterized in that it changes the opening degree of the first opening / closing section or the second opening / closing section according to the driving speed. According to the driving airflow control device of the present invention, by changing the opening degree of the first opening / closing section according to the driving speed, the wind speed of the driving air blown out towards the rear from the first rear opening can be changed. Similarly, by changing the opening degree of the second opening / closing section according to the driving speed, the wind speed of the driving air blown out downward from the second rear opening can be changed.

[0068] Furthermore, in the airflow control device according to an embodiment of the present invention, the calculation control unit is characterized in that, in the first operating mode, the opening degree of the first opening / closing part decreases as the driving speed increases. According to the airflow control device of the present invention, the airflow blown out from the first rear opening to the rear during high-speed driving can be accelerated by the flow contraction effect, further accelerating the airflow on the rear side of the rear tires and improving aerodynamic performance.

[0069] Furthermore, in the driving airflow control device according to an embodiment of the present invention, the first rear opening is positioned further rearward than the second rear opening. According to the driving airflow control device of the present invention, by positioning the first rear opening towards the rear, high-speed driving airflow can be more effectively discharged from the first rear opening toward the rear. In addition, by positioning the second rear opening close to the rear tire, the upward movement of dust that is kicked up by the rotation of the rear tire can be effectively suppressed by the driving airflow blown out from the second rear opening.

[0070] Furthermore, in the driving airflow control device according to an embodiment of the present invention, the second rear opening is positioned lower than the first rear opening. According to the driving airflow control device of the present invention, by positioning the second rear opening lower, the upward movement of dust that is kicked up by the rotation of the rear tires can be effectively suppressed by the driving airflow blown out from the second rear opening.

[0071] Although embodiments of the present invention have been described above, the present invention is not limited thereto, and modifications are possible without departing from the spirit of the invention. Furthermore, the above-described embodiments can be combined with each other. [Explanation of Symbols]

[0072] 10 vehicles 11 Car body 12 Underbody of the vehicle 13 Front tire 14 Rear tire 15. Vehicle speed sensor 16. Calculation Control Unit 17 Tire Hood 20. Driving airflow control device 21 Airflow channel 22 Front opening 23 1st rear opening 24 Second rear opening 25 First opening / closing section 26. Second opening / closing section

Claims

1. This is a running airflow control device that controls the airflow under a moving vehicle. It comprises a travel air passage, a front opening, a first rear opening, and a second rear opening. The aforementioned airflow path is formed from the inside of the vehicle width direction relative to the rear tire to the rear side of the rear tire. The aforementioned front opening is formed on the front end side of the airflow passage, The first rear opening is formed on the rear end side of the airflow passage and opens toward the rear. The airflow control device is characterized in that the second rear opening is formed on the rear end side of the airflow passage and opens downward.

2. It further comprises a vehicle speed sensor, a first opening / closing unit, a second opening / closing unit, and a calculation control unit. The vehicle speed sensor detects the speed at which the vehicle is traveling, The first opening / closing section is configured to open or close the first rear opening. The second opening / closing section is configured to open or close the second rear opening. The calculation control unit, If the travel speed exceeds a predetermined threshold speed, the first operation mode is executed; if the travel speed is less than or equal to the threshold speed, the second operation mode is executed. In the first operating mode, the first opening / closing part opens the first rear opening, and the second opening / closing part closes the second rear opening. The airflow control device according to claim 1, characterized in that, in the second operating mode, the first opening / closing unit closes the first rear opening and the second opening / closing unit opens the second rear opening.

3. The driving airflow control device according to claim 2, characterized in that the calculation control unit changes the opening degree of the first opening / closing unit or the second opening / closing unit according to the driving speed.

4. The driving airflow control device according to claim 2, characterized in that the calculation control unit reduces the opening degree of the first opening / closing part as the driving speed increases in the first operating mode.

5. The airflow control device according to claim 1, characterized in that the first rear opening is located further rearward than the second rear opening.

6. The airflow control device according to claim 1, characterized in that the second rear opening is located below the first rear opening.

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