Vehicle air duct structure

Abstract

The objective is to provide a vehicle airflow guide structure that can improve aerodynamic performance and cooling performance during driving. [Solution] The vehicle air duct structure 20 comprises an active grill shutter 21, a first air passage 22, a second air passage 23, an air passage switching unit 24, and a calculation control unit 25. The first air passage 22 is an air passage connecting the front of the vehicle 26 and the side of the vehicle 27 or the tire hood 28. The second air passage 23 is an air passage connecting the front of the vehicle 26 and the tire hood 28. The air passage switching unit 24 is configured to switch the airflow to either the first air passage 22 or the second air passage 23. The calculation control unit 25 switches the air passage switching unit 24 according to the driving conditions to guide the airflow to either the first air passage 22 or the second air passage 23.

Description

Technical Field

[0001] The present invention relates to an air guiding structure for a vehicle that guides traveling wind inside the vehicle body.

Background Art

[0002] When a vehicle is traveling, traveling wind is generated according to the vehicle speed. A front opening that communicates the engine room and the outside of the vehicle is formed in the front surface of the vehicle body, and a part of the traveling wind enters the engine room through the opening. The traveling wind that has entered the engine room cools the radiator and the condenser of the refrigeration cycle.

[0003] In addition, vehicles have also emerged in which an active grille shutter, which is an openable and closable shutter, is installed in the front opening of the vehicle body. By setting the active grille shutter in the open state, the traveling wind can be introduced into the engine room when the vehicle is traveling. Also, by setting the active grille shutter in the closed state, the engine room can be kept warm when the vehicle is traveling.

[0004] Patent Document 1 describes an invention related to a shutter opening / closing control device that is an active grille shutter. Specifically, in Patent Document 1, the control valve discharges the air flowing into the outside air inlet to the front duct side of the air duct according to the operating state of the vehicle. When the engine is in a high load state, the control valve closes the bypass passage, so that the air flowing into the outside air inlet is supplied to the radiator, and the vehicle engine room can be effectively cooled. Also, when the control valve opens the bypass passage, the flow rate of the air flowing into the inner side of the engine room decreases, thereby improving the aerodynamic performance of the vehicle.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

[0006] However, the inventions described in the aforementioned patent documents had room for improvement in terms of improving aerodynamic performance during vehicle travel.

[0007] Specifically, in the invention described in the background art, for example, if we focus on the left side of the vehicle, there is only one air duct that guides the airflow from the front to the side of the vehicle. Therefore, it is not possible to change the airflow path according to the vehicle's driving conditions, which presents a challenge in further improving the heat dissipation of the brakes and the aerodynamic effect.

[0008] This invention has been made in view of these problems, and the object of this invention is to provide a vehicle air guide structure that can improve aerodynamic performance and cooling performance during driving. [Means for solving the problem]

[0009] An embodiment of the present invention provides a vehicle air guide structure that is disposed at the front of a vehicle body and switches the airflow path of the air introduced into the vehicle body, comprising an active grille shutter, a first air passage, a second air passage, an air passage switching unit, and a calculation control unit, wherein the first air passage is an air passage connecting the front of the vehicle and the side of the vehicle or the tire hood, the second air passage is an air passage connecting the front of the vehicle and the tire hood, the air passage switching unit is configured to switch the airflow to either the first air passage or the second air passage, and the calculation control unit switches the air passage switching unit according to the driving conditions to guide the airflow to either the first air passage or the second air passage. [Effects of the Invention]

[0010] According to the vehicle air guide structure of the present invention, depending on the vehicle's driving conditions, the airflow can be directed to the first air passage by the airflow switching section, thereby directing the airflow to both sides and improving aerodynamic performance. On the other hand, depending on the vehicle's driving conditions, the airflow can be directed to the second air passage by the airflow switching section, thereby directing the airflow towards the brakes and effectively cooling the brakes. [Brief explanation of the drawing]

[0011] [Figure 1] This is a perspective view showing a vehicle equipped with a vehicle air guide structure according to an embodiment of the present invention. [Figure 2] This is a front view showing a vehicle equipped with a vehicle air guide structure according to an embodiment of the present invention. [Figure 3] This is a lower cross-sectional view showing a vehicle air guide structure according to an embodiment of the present invention and its vicinity. [Figure 4] This is a block diagram showing the connection configuration of a vehicle air guide structure according to an embodiment of the present invention. [Figure 5] This is a flowchart showing the operation of a vehicle air guide structure according to an embodiment of the present invention. [Figure 6] This is a lower cross-sectional view showing the first operating mode of a vehicle air guide structure according to an embodiment of the present invention. [Figure 7] This is a lower cross-sectional view showing a second operating mode of a vehicle air guide structure according to an embodiment of the present invention. [Figure 8] This is a lower cross-sectional view showing a third operating mode of a vehicle air guide structure according to an embodiment of the present invention. [Modes for carrying out the invention]

[0012] Hereinafter, a vehicle air guide structure 20 and a vehicle 10 according to an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, the directions of front, rear, up, down, left, and right will be used, but left and right will refer to the left and right when the vehicle 10 is viewed from the front. Furthermore, in the following description, the same reference numerals will be used for the same components in principle, and repeated explanations will be omitted.

[0013] FIG. 1 is a perspective view showing a vehicle 10 equipped with a vehicle air guiding structure 20. FIG. 2 is a front view showing the vehicle 10 equipped with the vehicle air guiding structure 20.

[0014] 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.

[0015] The vehicle 10 includes a vehicle body 11. An engine room 13 is provided in the front portion of the vehicle body 11. For example, an engine, a battery, or the like is provided inside the engine room 13. The vehicle air guiding structure 20 according to the present embodiment is provided in the engine room 13 or in the vicinity thereof.

[0016] The vehicle body 11 has a vehicle front portion 26 and a vehicle side portion 27. The vehicle front portion 26 is a surface facing the front of the vehicle body 11. The vehicle side portion 27 is a surface facing the right or left of the vehicle body 11. An active grille shutter 21 is provided in the vehicle front portion 26 or on the rear side thereof.

[0017] The active grille shutter 21 has a shutter mechanism that opens and closes. By setting the active grille shutter 21 to the open state, the engine room 13 is communicated with the outside of the vehicle, and the front side of the vehicle 10 and the engine room 13 are communicated through an opening formed in the active grille shutter 21, and the running wind can be introduced into the engine room 13. On the other hand, by setting the active grille shutter 21 to the closed state, the engine room 13 is not communicated with the outside of the vehicle, and the running wind is not introduced into the engine room 13. Here, the running wind is the flow of air generated when the vehicle 10 runs.

[0018] Further, the active grille shutter 21 may be disposed on the rear side of a front bumper beam not shown here. In this case, a concave portion is formed by the active grille shutter 21 being recessed rearward from the front portion of the vehicle 26. In such a case, when the vehicle 10 is moving forward, if the active grille shutter 21 is in the closed state, turbulent flow may occur from the front portion of the active grille shutter 21 toward the outside in the vehicle width direction, and the aerodynamic performance of the vehicle 10 may deteriorate. As will be described later, in the present embodiment, by forming an air curtain along the side portion 27 of the vehicle by the vehicle air guiding structure 20, the aerodynamic performance is improved even in such a case.

[0019] A first inlet 221 and a second inlet 231 are disposed at the lower right end of the front portion 26 of the vehicle. The first inlet 221 and the second inlet 231 are openings formed in the front portion 26 of the vehicle, and are openings for taking in the traveling wind when the vehicle 10 is moving forward. The first inlet 221 is formed on the outside in the vehicle width direction. The second inlet 231 is formed on the inside in the vehicle width direction. As shown in FIG. 2, a first inlet 221 and a second inlet 231 are also disposed at the lower left end of the front portion 26 of the vehicle.

[0020] FIG. 3 is a bottom cross-sectional view showing the vehicle air guiding structure 20 and its vicinity. FIG. 3 is a cross-sectional view taken along the cutting plane line A-A in FIG. 2. The A-A cutting plane is a cross-section including the front-rear direction and the left-right direction. In FIG. 3, only the right portion of the front part of the vehicle 10 is shown. Also, in the left portion of the front part of the vehicle 10, the vehicle air guiding structure 20 is disposed in a symmetric configuration in the left-right direction. That is, the vehicle air guiding structure 20 is disposed in the front part of the vehicle 10 in the right side portion and the left side portion. Also, in the following description, the operation of the vehicle air guiding structure 20 disposed in the right portion of the vehicle body 11 will be described. Here, the vehicle air guiding structure 20 (not shown) disposed in the left portion of the vehicle air guiding structure 20 also operates in the same manner as the vehicle air guiding structure 20 disposed in the right portion.

[0021] As described above, an active grille shutter 21 is positioned in the center of the front 26 of the vehicle body 11 in the left-right direction. A tire hood 28 is formed at the right end of the front of the vehicle body 11. A tire 29 is positioned inside the tire hood 28. The tire 29 is supported by a tire wheel 30. A disc rotor 31, which constitutes the brake 12, is fixed to the inside of the tire wheel 30. A caliper (not shown), which constitutes the brake 12, is positioned near the disc rotor 31. When the vehicle 10 is in motion, if an occupant presses a brake pedal (not shown), the caliper (not shown) clamps the disc rotor 31, restricting the rotation of the tire wheel 30 and tire 29, and braking the vehicle 10. This causes the vehicle 10 to decelerate or come to a stop.

[0022] The vehicle air duct structure 20 is located on the right side, which is the outer side in the width direction. The vehicle air duct structure 20 is located at the front of the vehicle body 11 and is a device that switches the airflow path of the driving air introduced into the vehicle body 11. Specifically, the vehicle air duct structure 20 comprises an active grill shutter 21, a first air passage 22, a second air passage 23, an air passage switching unit 24, and a calculation control unit 25. The calculation control unit 25 is shown in Figure 4.

[0023] The first air passage 22 is an air passage connecting the front part 26 of the vehicle and the side part 27 of the vehicle or the tire hood 28. The first air passage 22 is an air tunnel having a first inlet 221 into which the airflow is introduced and a first outlet 222 into which the airflow is discharged. The first inlet 221 is located on the right side of the front part 26 of the vehicle, which is wider than the active grille shutter 21. The first outlet 222 is located on the front end side of the tire hood 28, which is on the right end side. Here, the first outlet 222 may also be located on the side part 27 of the vehicle, which is forward of the tire hood 28. As mentioned above, the first inlet 221 is located on the right side of the first outlet 222, which is wider than the first outlet 222.

[0024] The second air passage 23 is an air passage connecting the front section 26 of the vehicle and the tire hood 28. The second air passage 23 is an air tunnel having a second inlet 231 into which the airflow is introduced and a second outlet 232 into which the airflow is discharged. The second inlet 231 is located in the front section 26 of the vehicle, immediately adjacent to the right end of the active grill shutter 21. The second outlet 232 is located inside the tire hood 28, on the front left end side.

[0025] The airflow switching section 24 is configured to switch the airflow so that it is directed to either the first airflow passage 22 or the second airflow passage 23. The airflow switching section 24 is a damper 241 configured to block either the first airflow passage 22 or the second airflow passage 23.

[0026] The damper 241 is a plate-shaped member and is sized to be able to close the first inlet 221 or the second inlet 231. The damper 241 is rotatably mounted relative to the vehicle body 11 by a damper drive unit 242. The damper drive unit 242 is an actuator such as a motor, which rotates the damper 241 with the end of the second inlet 231 as the center of rotation.

[0027] Figure 4 is a block diagram showing the connection configuration of the vehicle air duct structure 20.

[0028] The arithmetic control unit 25 consists of semiconductor elements such as a CPU (Central Processing Unit). The arithmetic control unit 25 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 25 executes the functions and methods described later.

[0029] Referring to Figure 3, in this embodiment, when the active grill shutter 21 is closed and the brake 12 is not operating, the calculation control unit 25 switches the airflow switching unit 24 to direct airflow into the first air passage 22. Also, when the active grill shutter 21 is closed and the brake 12 is operating, the calculation control unit 25 switches the airflow switching unit 24 to direct airflow into the second air passage 23. Furthermore, when the active grill shutter 21 is open, the calculation control unit 25 switches the airflow switching unit 24 to direct airflow into the first air passage 22. These operations will be described later with reference to Figure 5, etc.

[0030] The vehicle air duct structure 20 includes a calculation control unit 25, a brake sensor 32, an acceleration sensor 33, an active grill shutter 21, and a damper drive unit 242. The brake sensor 32 and the acceleration sensor 33 are connected to the input terminals of the calculation control unit 25. The active grill shutter 21 and the damper drive unit 242 are connected to the output terminals of the calculation control unit 25. As will be described later, the calculation control unit 25 guides the airflow to either the first air passage 22 or the second air passage 23 by switching the air passage switching unit 24 according to the driving conditions.

[0031] The brake sensor 32 is a sensor that detects the operation of the brake 12 as described above. The brake sensor 32 can be a sensor that detects whether or not the caliper is gripping the disc rotor 31 as described above. If the caliper is gripping the disc rotor 31 as described above, the brake sensor 32 transmits a signal to the calculation control unit 25 to indicate this.

[0032] The acceleration sensor 33 can be a sensor that detects acceleration acting on the vehicle body 11. When the acceleration sensor 33 detects acceleration acting on the vehicle body 11 that decelerates the vehicle 10, it transmits a signal to the arithmetic control unit 25 to that effect. In other words, the acceleration sensor 33 can detect that the brake 12 is operating by detecting acceleration that decelerates the vehicle 10.

[0033] The brake sensor 32 or the acceleration sensor 33 are both sensors that detect when the aforementioned brake 12 is operating. Both the brake sensor 32 and the acceleration sensor 33 may be provided, or only one of them may be provided.

[0034] As mentioned above, the active grill shutter 21 is a device fitted into an opening formed in the front part 26 of the vehicle body 11. Based on instructions from the calculation control unit 25, when the active grill shutter 21 is opened, airflow is introduced into the engine compartment 13 through the active grill shutter 21. On the other hand, based on instructions from the calculation control unit 25, when the active grill shutter 21 is closed, airflow is not introduced into the engine compartment 13.

[0035] The damper drive unit 242 is a device such as a motor that rotates the airflow switching unit 24 shown in Figure 3. Based on instructions from the calculation control unit 25, the airflow switching unit 24 closes either the second inlet 231 or the first inlet 221.

[0036] Figure 5 is a flowchart illustrating the operation of the vehicle air duct structure 20. Based on Figure 5 and referring to the figures mentioned above, the operation of the vehicle air duct structure 20 while the vehicle 10 is in motion will be explained. As will be described later, the operation of the vehicle air duct structure 20 includes a first operating mode, a second operating mode, and a third operating mode. The first operating mode is shown in Figure 6, the second operating mode in Figure 7, and the third operating mode in Figure 8. Figures 6, 7, and 8 are cross-sections corresponding to Figure 3 mentioned above. In Figures 6, 7, and 8, the airflow generated by the vehicle 10 in motion is shown by a dashed line.

[0037] In step S10, the calculation control unit 25 drives the vehicle 10. Specifically, based on the occupant's operation, the calculation control unit 25 drives the vehicle 10 by rotating the tires 29 using the engine or motor as the drive source.

[0038] In step S11, the arithmetic control unit 25 determines whether the active grill shutter 21 is open or not.

[0039] If the answer in step S11 is YES, that is, if the active grill shutter 21 is in the open state, the calculation control unit 25 proceeds to step S13.

[0040] If the answer in step S11 is NO, that is, if the active grill shutter 21 is in the closed state, the calculation control unit 25 proceeds to step S12.

[0041] In step S12, the arithmetic control unit 25 determines whether the brake 12 is operating based on the output of the brake sensor 32 or the acceleration sensor 33.

[0042] If the answer in step S12 is YES, that is, if the brake 12 is operating, the arithmetic control unit 25 proceeds to step S15.

[0043] If the answer in step S12 is NO, that is, if the brake 12 is not operating, the calculation control unit 25 proceeds to step S14.

[0044] In step S13, the calculation control unit 25 executes the first operation mode. The first operation mode will be described with reference to Figure 6. In the first operation mode, the calculation control unit 25 drives the damper drive unit 242 to rotate the damper 241, and closes the second inlet 231 of the second air passage 23 with the damper 241.

[0045] In this manner, a portion of the airflow is introduced into the engine compartment 13 via the active grille shutter 21. The airflow introduced into the engine compartment 13 exchanges heat with heat-generating equipment (not shown), such as an engine, battery, motor, etc. This cools the heat-generating equipment such as the engine housed in the engine compartment 13. The airflow, after cooling the engine, etc., is introduced into the tire hood 28. While the brake 12 is operating, the caliper (not shown) clamps the disc rotor 31, causing the clamping area to become hot. The airflow introduced into the tire hood 28 passes over this clamping area, cooling the brake 12 and improving braking performance.

[0046] Furthermore, another portion of the airflow is introduced into the first ventilation passage 22. Specifically, the airflow is introduced into the first ventilation passage 22 via the first inlet 221 and discharged to the right side of the vehicle body 11 via the first outlet 222. This airflow is discharged to the front end of the tire hood 28, or to a position further forward than the tire hood 28. The discharged airflow is blown along the vehicle side section 27, which is the right side of the vehicle body 11. This allows an air curtain to be formed on the right side of the tire hood 28. As a result, the aerodynamic performance of the tire hood 28 and its vicinity is improved, and steering performance and stability during driving can be improved.

[0047] On the other hand, since the damper 241 closes the second inlet 231, no airflow is introduced into the second ventilation passage 23 in the first operating mode.

[0048] In step S14, referring to Figure 7, the calculation control unit 25 executes the second operating mode. In the second operating mode, the calculation control unit 25 drives the damper drive unit 242 to close the second inlet 231 of the second air passage 23. Also, in step S14, as described above, the active grill shutter 21 is in the closed state. In this situation, the airflow flows along the front of the vehicle 26 toward the right, which is outward in the width direction, and then is introduced into the first air passage 22 from the first inlet 221 and discharged from the first outlet 222. This creates an air curtain on the right side of the tire hood 28. Therefore, the aerodynamic performance of the tire hood 28 and its vicinity is improved, and steering performance and stability during driving can be improved.

[0049] In step S15, the calculation control unit 25 executes the third operation mode shown in Figure 8. In the third operation mode, the calculation control unit 25 drives the damper drive unit 242 to close the first inlet 221 with the damper 241. Also in the third operation mode, the active grill shutter 21 is in the closed state. In this situation, the airflow flows outward in the width direction to the right along the front of the vehicle 26, then is introduced into the second air passage 23 via the second inlet 231, and discharged to the tire hood 28 from the second outlet 232. After that, the airflow is blown to the brake 12. This effectively cools the brake 12 and improves the braking performance of the vehicle 10.

[0050] In step S16, the vehicle 10 comes to a stop. This concludes the explanation of the operation of the vehicle air guide structure 20 when the vehicle 10 is traveling.

[0051] The technical concepts that can be understood from the above-mentioned embodiment, along with their effects, are described below.

[0052] The present invention provides a vehicle air guide structure that is disposed at the front of a vehicle body and switches the airflow path of the airflow introduced into the vehicle body. The structure comprises an active grille shutter, a first air passage, a second air passage, an air passage switching unit, and a calculation control unit. The first air passage is an air passage connecting the front of the vehicle to the side of the vehicle or the tire hood. The second air passage is an air passage connecting the front of the vehicle to the tire hood. The air passage switching unit is configured to switch the airflow to either the first or second air passage. The calculation control unit switches the air passage switching unit according to the driving conditions to guide the airflow to either the first or second air passage. According to the present invention, the vehicle air guide structure can improve aerodynamic performance by directing the airflow to the first air passage via the air passage switching unit according to the driving conditions of the vehicle, thereby directing the airflow to both sides. On the other hand, depending on the vehicle's driving conditions, the airflow switching section directs the airflow to the second airflow passage, directing the airflow towards the brakes, thereby effectively cooling the brakes.

[0053] Furthermore, in the vehicle air duct structure of the present invention, the calculation control unit, when the active grill shutter is closed and the brakes are not operating, switches the airflow switching unit to guide the airflow through the first air passage. According to the vehicle air duct structure of the present invention, the airflow guided through the first air passage passes over the side of the vehicle, thereby improving the aerodynamic performance during vehicle operation.

[0054] Furthermore, in the vehicle air duct structure of the present invention, the calculation control unit, while the active grill shutter is closed and the brakes are operating, switches the airflow switching unit to guide the airflow through the second air passage. According to the vehicle air duct structure of the present invention, the airflow guided through the second air passage is blown onto the brakes located inside the tire hood. Therefore, the brakes, which generate heat during braking, can be effectively cooled.

[0055] Furthermore, in the vehicle air duct structure of the present invention, the calculation control unit is characterized in that, when the active grill shutter is open, it switches the airflow switching unit to guide the airflow through the first air passage. According to the vehicle air duct structure of the present invention, when the active grill shutter is open, the airflow introduced into the engine compartment via the active grill shutter is blown into the wheel well, thereby cooling the brakes. In addition, by switching the airflow switching unit, the airflow guided into the first air passage passes through the side of the vehicle, thereby improving the aerodynamic performance during vehicle operation.

[0056] Furthermore, in the vehicle air duct structure of the present invention, the air duct switching section is characterized by being a damper configured to block either the first air duct or the second air duct. According to the vehicle air duct structure of the present invention, the damper acting as the air duct switching section makes it easy to switch between the first air duct and the second air duct.

[0057] Furthermore, in the vehicle air guide structure of the present invention, the first air passage has a first inlet into which the airflow is introduced and a first outlet out which the airflow is discharged, and the second air passage has a second inlet into which the airflow is introduced and a second outlet out which the airflow is discharged, and the first outlet is arranged to be further outward in the width direction than the second outlet. According to the vehicle air guide structure of the present invention, by arranging the first outlet to be further outward in the width direction, the airflow can be discharged from the first outlet along the side of the vehicle, thereby improving the aerodynamic effect when the vehicle is in motion.

[0058] 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]

[0059] 10 vehicles 11 Car body 12 Brake 13. Engine Room 20. Vehicle air duct structure 21 Active Grille Shutter 22 1st ventilation duct 221 First Inlet 222 1st outlet 23 2nd ventilation duct 231 Second Inlet 232 2nd outlet 24 Airflow switching section 241 Damper 242 Damper drive unit 25. Arithmetic Control Unit 26 Front of the vehicle 27 Side view of the vehicle 28 Tire Hood 29 tires 30 Tire and Wheel 31 Disc rotors 32 Brake Sensor 33. Accelerometer

Claims

1. It is a vehicle air guide structure located at the front of the vehicle body that switches the airflow path of the air being introduced into the vehicle body while driving. It comprises an active grille shutter, a first air passage, a second air passage, an air passage switching unit, and a calculation control unit. The first ventilation passage is an air passage connecting the front of the vehicle to the side of the vehicle or the tire hood. The second ventilation passage is an air passage connecting the front of the vehicle and the tire hood. The airflow switching unit is configured to switch the airflow so that it is directed to either the first airflow passage or the second airflow passage. The aforementioned calculation control unit is characterized by guiding the airflow through the first air passage or the second air passage by switching the air passage switching unit according to the driving conditions, thereby providing a vehicle air guide structure.

2. The vehicle air guide structure according to claim 1, characterized in that the calculation control unit guides the running air to the first air passage by switching the air passage switching unit when the active grill shutter is closed and the brake is not operating.

3. The vehicle air guide structure according to claim 1, characterized in that the calculation control unit guides the running air to the second air passage by switching the air passage switching unit while the brake is operating when the active grill shutter is closed.

4. The vehicle air guide structure according to claim 1, characterized in that the calculation control unit guides the running air to the first air passage by switching the air passage switching unit when the active grill shutter is open.

5. The vehicle air guide structure according to claim 1, characterized in that the airflow switching section is a damper configured to block either the first airflow passage or the second airflow passage.

6. The first ventilation passage has a first inlet into which the running air is introduced, and a first outlet out which the running air is discharged. The second ventilation passage has a second inlet into which the airflow is introduced, and a second outlet out which the airflow is discharged. The vehicle air duct structure according to claim 1, characterized in that the first outlet is disposed further outward in the width direction than the second outlet.

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