vehicle

Abstract

The present invention provides a vehicle equipped with an underbody cover that can be moved up and down, and which can reduce the loss of kinetic energy by lowering the underbody cover while driving. [Solution] The vehicle comprises a pair of left and right front wheels, a pair of left and right undercovers 12, a drive unit, and a lateral sealing member 19. The pair of left and right undercovers 12 are located in the front-rear direction, extending from near the front end of the front wheels forward, spaced apart from each other between the front wheels in the vehicle width direction, and each is provided to cover the bottom surface of the vehicle body. The lateral sealing member 19 airtightly seals the space between each side edge of the left and right undercovers 12 and the vehicle body when the undercovers 12 are in a lowered and deployed state. When each undercover 12 is in the deployed state, the portion from the rear edge forward has a bottom flat portion where the bottom surface is parallel to the road surface.

Description

TECHNICAL FIELD

[0001] The present invention relates to vehicles, and particularly relates to the structure of the front lower portion of a vehicle.

BACKGROUND ART

[0002] Vehicles are required to reduce vortices generated during traveling to reduce kinetic energy loss. When a vehicle is traveling, air also flows into the lower side of the vehicle from between the front bumper and the road surface, and vortices may be generated below the vehicle to cause kinetic energy loss. Structures intended to suppress the generation of such vortices under the vehicle are disclosed in Patent Documents 1 to 3.

[0003] Patent Documents 1 and 2 disclose a vehicle provided with an undercover arranged to extend from the lower portion of the front end of the front bumper to near the rear end of the front wheel. The undercover has a structure in which a plate-shaped front cover portion disposed forward of the front end portion of the wheel house and a plate-shaped rear cover portion disposed rearward of the front end portion of the wheel house are connected to each other. The undercover is connected to an actuator, and is configured to be capable of changing state between a stowed state in which the connecting portion between the front cover portion and the right rear cover portion is raised upward, and a deployed state in which the connecting portion is lowered downward. In the undercover in the deployed state, the front cover portion is inclined such that its height displaces upward as it goes forward from the connecting portion, and the rear cover portion is provided so as to be inclined such that its height displaces upward as it goes rearward from the connecting portion.

[0004] Patent Document 3 discloses a vehicle that is equipped with rectifying members (undercovers) disposed on each of the left and right sides in the vehicle width direction, and an air actuator that raises / lowers the rectifying members. Each rectifying member has a boat-like shape having a bottom wall, side walls, and a rear wall, and is disposed in front of each of the left and right front wheels. When the rectifying member is brought into the lowered state by the air actuator, the lower surface of the bottom wall of the rectifying member is provided with a curved surface whose height displaces from the upper side to the lower side as it goes from the front to the rear. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2023-10984 [Patent Document 2] U.S. Patent Application Publication No. 2023 / 0099045 [Patent Document 3] Japanese Patent Publication No. 2007-30549 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the structures disclosed in the above-mentioned Patent Documents 1-3 are considered to have room for improvement in reducing the loss of kinetic energy when the vehicle is in motion. Specifically, when the vehicle is in motion, the air flowing beneath the vehicle also collides with the tire tread at the front end of the front wheel, but in the structures disclosed in Patent Documents 1-3, it is considered that the airflow near the front end of the front wheel becomes stagnant. For this reason, the structures disclosed in Patent Documents 1-3 are considered to have room for improvement in reducing the loss of kinetic energy when the vehicle is in motion by suppressing the stagnation of the airflow near the front end of the front wheel.

[0007] Specifically, in the structures disclosed in the above-mentioned Patent Documents 1-3, when the under cover is deployed, the under cover is positioned such that the gap with the road surface gradually narrows from the front of the vehicle towards the front end of the front wheel. Therefore, it is thought that the air pressure becomes high in the area directly in front of the front wheel. Consequently, in the structures disclosed in the above-mentioned Patent Documents 1-3, it is thought that stagnation occurs in the airflow near the front end of the front wheel during driving. Thus, it is thought that there is room for further improvement in the structures disclosed in the above-mentioned Patent Documents 1-3 to reduce the loss of kinetic energy.

[0008] The present invention aims to solve the above-mentioned problems and provides a vehicle equipped with an under cover that can move up and down, and which can reduce the loss of kinetic energy by lowering the under cover while driving. [Means for solving the problem]

[0009] A vehicle according to one aspect of the present invention comprises a pair of left and right front wheels, a pair of left and right undercovers, a drive unit, and a lateral sealing member. The pair of left and right front wheels are positioned at both ends in the width direction of the vehicle at the front of the vehicle. The pair of left and right undercovers are positioned in the longitudinal direction of the vehicle, from near the front ends of the pair of left and right front wheels forward, spaced apart from each other between the pair of left and right front wheels in the width direction, and each is provided to cover the bottom surface of the vehicle body. The drive unit moves the pair of left and right undercovers up and down. The lateral sealing member airtightly seals the space between each side edge of the pair of left and right undercovers and the vehicle body when the pair of left and right undercovers are lowered and deployed by the drive unit.

[0010] In the vehicle according to this embodiment, each of the left and right pair of undercovers, when in the deployed state, has a flat bottom portion in the forward part from the rear edge, where the bottom surface is parallel to the road surface.

[0011] The vehicle according to the above embodiment is equipped with a pair of left and right undercovers, each having a flat bottom surface. The flat bottom surface of each undercover is the part that is parallel to the road surface when in the deployed state. Therefore, in the vehicle according to the above embodiment, when the vehicle is driven with the left and right pair of undercovers deployed, the pressure decreases as it moves towards the rear of the flat bottom surface. Thus, in a vehicle that can be equipped with a pair of left and right undercovers, each having a flat bottom surface, when the vehicle is driven with the left and right pair of undercovers deployed, air hits the front wheels straight in the front-rear direction, suppressing air stagnation in that area and reducing the loss of kinetic energy.

[0012] Furthermore, the vehicle according to the above embodiment does not have an under cover integrally formed in the vehicle width direction, but rather has a left under cover and a right under cover that are spaced apart from each other in the vehicle width direction. For this reason, the increase in vehicle weight and manufacturing cost is suppressed compared to the case in which the vehicle according to the above embodiment has an under cover integrally formed in the vehicle width direction.

[0013] Furthermore, the vehicle according to the above embodiment is equipped with a lateral sealing member that airtightly seals the space between each side edge of the left and right undercovers and the vehicle body. Therefore, when the vehicle is driven with each of the left and right undercovers deployed, the outflow of air from the powertrain room above the undercovers (the area where the engine, traction motor, etc., which are the driving source, are mounted) to the sides of each undercover is suppressed. As a result, when the vehicle according to the above embodiment is driven with each of the left and right undercovers deployed, the generation of vortices around each undercover, including the sides, is suppressed, and the loss of kinetic energy can be effectively reduced.

[0014] Furthermore, since the vehicle according to the above embodiment is equipped with a drive unit that moves a pair of left and right undercovers up and down, it is possible to drive with the undercovers raised without lowering them when driving on roads with large irregularities or when each undercover and its surrounding parts are frozen in a low-temperature environment. Therefore, the vehicle according to the above embodiment can suppress deformation and damage to each undercover and its surrounding parts caused by driving and the up and down movement of the undercovers.

[0015] In the above, "parallel" includes not only cases where the bottom surface of the flat section of each undercover is perfectly parallel to the road surface, but also cases where it is slightly inclined to the road surface (for example, 2 degrees or less). The same applies hereafter.

[0016] In the vehicle according to the above embodiment, the lateral sealing member may be a bellows-shaped membrane member.

[0017] The vehicle according to the above embodiment is equipped with a lateral sealing member made of a bellows-shaped membrane member, so when each under cover is deployed, the bellows-shaped lateral sealing member can be deployed in accordance with the downward movement of the under cover.

[0018] On the other hand, when each under cover is raised and stored, the bellows are folded, preventing any part of the lateral sealing member from undesirably protruding from the sides of the under cover. Therefore, in the above configuration, when the vehicle is driven with each under cover in the stored position, damage to the lateral sealing member from flying stones or other objects is suppressed.

[0019] In the vehicle according to the above embodiment, the bellows-shaped membrane member may be provided such that the folds extend in the front-rear direction of the vehicle.

[0020] In the above-described vehicle, the lateral sealing members are arranged such that the folds extend in the front-to-back direction, thereby suppressing resistance to the air flowing from the front during driving. Therefore, the above-described vehicle can more effectively reduce the loss of kinetic energy during driving.

[0021] In the vehicle according to the above embodiment, the vehicle body may be provided with an intermediate bracket fixed to the perimeter frame. In this case, the upper part of each of the lateral sealing members may be fixed to the intermediate bracket.

[0022] In the above-described vehicle, since the upper part of the lateral sealing member is fixed to the intermediate bracket, the lateral sealing member and under cover can be pre-assembled to the intermediate bracket during vehicle assembly, and this assembly can then be mounted to the perimeter frame. Therefore, the above-described vehicle can improve the efficiency of manufacturing operations and reduce manufacturing costs.

[0023] The vehicle according to the above aspect may further include a front bumper and a front seal member. The front bumper is disposed in front of the pair of left and right front wheels, and is provided to extend in the vehicle width direction at the front end of the vehicle. The front seal member airtightly seals between each front edge portion of the pair of left and right undercovers and the front bumper when in the deployed state.

[0024] Since the vehicle according to the above aspect further includes the front seal member, it is possible to suppress air from being drawn out from between the undercovers and the front bumper when traveling with each undercover in the deployed state. Therefore, the vehicle according to the above aspect also suppresses the generation of eddy currents below the front portion of the undercovers, and can more reliably reduce the loss of kinetic energy.

[0025] In the vehicle according to the above aspect, the front seal member may have a tubular shape having a hollow portion in a cross section.

[0026] Since the vehicle according to the above aspect includes the front seal member having a tubular shape, when each undercover is lowered, the front seal member is elastically deformed between itself and the front bumper, so that sealing can be performed without gaps. In this case, since the front seal member has a hollow portion, compared with the case where a solid seal member is adopted, the front seal member is elastically deformed in the cross-sectional direction, so that gaps between the front seal member and the undercovers as well as the front bumper can be more reliably eliminated.

[0027] In the vehicle according to the above aspect, when assuming a vehicle central axis that passes through the center in the vehicle width direction and extends in the front-rear direction of the vehicle, the pair of left and right undercovers may be arranged symmetrically to each other with respect to the vehicle central axis, and may have shapes that are symmetrical to each other left and right.

[0028] In the above-described vehicle, the left and right undercovers are arranged and shaped symmetrically with respect to the vehicle's central axis, allowing air flowing from the front to the underside of the vehicle to flow symmetrically in the vehicle's width direction. Therefore, the above-described vehicle is suitable for reducing kinetic energy loss while ensuring handling stability during driving.

[0029] In the vehicle according to the above embodiment, an outside temperature measuring unit, a vehicle speed measuring unit, and a control unit may be further provided. The outside temperature measuring unit measures the outside temperature. The vehicle speed measuring unit measures the vehicle's speed. The control unit acquires outside temperature information from the outside temperature measuring unit and vehicle speed information from the vehicle speed measuring unit, and based on the acquired information, issues a command to the drive unit to raise or lower the pair of left and right undercovers.

[0030] In the above-described vehicle, the control unit acquires outside temperature information and vehicle speed information, and based on the acquired information (vehicle information), issues an upward / downward command to the drive unit. Therefore, when the outside temperature is low and there is a concern that the road surface may freeze or that the undercovers and the mechanisms of the surrounding parts may freeze, the left and right undercovers will not be lowered even if the vehicle speed is high. Also, when the vehicle speed is low, it is presumed that the vehicle is driving in an urban area, so the undercovers will not be lowered. As a result, in the above-described vehicle, when the outside temperature is relatively low or the vehicle speed is relatively low, the undercovers can be raised to suppress deformation and damage to the undercovers and the surrounding parts.

[0031] On the other hand, in the above-described configuration, when the outside temperature is relatively high and the vehicle speed is judged to be relatively high, the pair of undercovers on the left and right sides are lowered because freezing and urban driving conditions are not expected. This suppresses the generation of vortices near the front end of the front wheels and reduces the loss of kinetic energy. [Effects of the Invention]

[0032] In each of the above embodiments, the vehicle can reduce kinetic energy loss by raising the under cover to suppress deformation or damage to the under cover and its surrounding parts during driving, and by lowering the under cover to suppress the occurrence of stagnation in airflow near the front end of the front wheels. [Brief explanation of the drawing]

[0033] [Figure 1] This is a perspective view showing the front lower part of the vehicle according to the embodiment. [Figure 2] This is a bottom view showing the front lower part of the vehicle. [Figure 3] This is a schematic diagram showing the structure related to the movement of the underbody cover. [Figure 4] (a) is a side view showing the deployed state with the under cover lowered, and (b) is a side view showing the stowed state with the under cover raised. [Figure 5] This is a partial perspective view showing the surrounding structure of the underbody. [Figure 6] This is an exploded perspective view showing the arrangement of the front sealing member and the side sealing member. [Figure 7] This is a cross-sectional view showing the section along line VII-VII in Figure 5. [Figure 8] This is a cross-sectional view showing the section along line VIII-VIII in Figure 5. [Figure 9] This is a block diagram showing the control configuration related to the movement of the underbody cover. [Figure 10] This diagram shows the reference maps that are pre-stored in the reference map storage unit of the control unit. [Figure 11] This is a flowchart illustrating the movement control of the underbody cover performed by the control unit. [Figure 12] (a) is a schematic diagram showing the under cover in the deployed state in a vehicle according to the embodiment, (b) is a graph showing the pressure change in the longitudinal direction under the under cover, and (c) is a schematic diagram for explaining the airflow at the front underside of the vehicle. [Figure 13](a) is a schematic diagram showing the under cover in the deployed state of a vehicle relating to the comparative example, (b) is a graph showing the pressure change in the longitudinal direction under the under cover, and (c) is a schematic diagram to explain the airflow at the front underside of the vehicle. [Modes for carrying out the invention]

[0034] Embodiments of the present invention will be described below with reference to the drawings. The embodiments described below are illustrative examples of the present invention, and the present invention is not limited to these embodiments except for its essential configuration.

[0035] Furthermore, in the diagrams used in the following explanation, "FR" indicates the front of the vehicle, "RR" indicates the rear of the vehicle, "LH" indicates the left side of the vehicle, "RH" indicates the right side of the vehicle, "UP" indicates the top of the vehicle, and "LO" indicates the bottom of the vehicle.

[0036] 1. Structure of the front lower part of vehicle 1 The structure of the front lower part of vehicle 1 according to this embodiment will be explained with reference to Figures 1 to 3.

[0037] As shown in Figure 1, the vehicle 1 is equipped with a pair of front wheels 11 (left front wheel 11L, right front wheel 11R), a pair of undercovers 12 (left undercover 12L, right undercover 12R), a front bumper 13, a pair of deflectors 14 (left deflector 14L, right deflector 14R), and a powertrain undercover (PT cover) 15 at the front lower part.

[0038] As shown in Figures 1 and 2, the left front wheel 11L is located in the left wheel well 1aL, and the right front wheel 11R is located in the right wheel well 1aR. That is, the pair of left and right front wheels 11 are located at both ends in the width direction of the vehicle at the front of the vehicle 1.

[0039] The left under cover 12L and the right under cover 12R are positioned in the area from near the front ends 11a of the pair of front wheels 11 in the front-rear direction to near the front end 13b of the front bumper 13, and are located between the pair of front wheels 11 in the vehicle width direction. The left under cover 12L and the right under cover 12R are spaced apart from each other in the vehicle width direction, and each is provided to cover a part of the underside of the vehicle body.

[0040] As shown in Figure 2, we assume a virtual axis (vehicle central axis) Ax1 that passes through the center of the vehicle width direction in vehicle 1 and extends in the longitudinal direction. In this case, the left under cover 12L and the right under cover 12R are arranged symmetrically with respect to the vehicle central axis Ax1 and have symmetrical shapes. In vehicle 1, each of the left under cover 12L and the right under cover 12R is provided such that its width in the vehicle width direction is 300 mm or more.

[0041] Furthermore, in this embodiment, the left and right pair of undercovers 12 are formed using a resin material (for example, PP: polypropylene).

[0042] Furthermore, the left under cover 12L and the right under cover 12R are each provided with a rear edge 12d that is straight along the vehicle width direction.

[0043] The front bumper 13 is positioned in front of the pair of front wheels 11 and extends in the width direction at the front end of the vehicle 1.

[0044] The left deflector 14L is located directly in front of the left front wheel 11L and is positioned close to the left side (outer side in the vehicle width direction) of the left under cover 12L. The right deflector 14R is located directly in front of the right front wheel 11R and is positioned close to the right side (outer side in the vehicle width direction) of the right under cover 12R.

[0045] The PT cover 15 is positioned close to the rear edges 12d of the pair of left and right undercovers 12 in the front-rear direction, and extends rearward from that point of proximity, avoiding the wheelhouses 1aL and 1aR. The PT cover 15 is positioned to cover the area below the powertrain (not shown) for driving, which is mounted in the powertrain room at the front of the vehicle 1. The powertrain of the vehicle 1 is not particularly limited, but could be, for example, an engine or a drive motor.

[0046] As shown in Figure 3, the vehicle 1 includes an actuator 17 and a link mechanism 16 that connects the actuator 17 to the under cover 12. Although Figure 3 shows one of the left and right under covers 12, and the link mechanism 16 and actuator 17 connected to that under cover 12, in the vehicle 1 according to this embodiment, the link mechanism 16 and actuator 17 are provided corresponding to the left and right under covers 12L and 12R, respectively.

[0047] In this embodiment, the actuator 17 and the link mechanism 16 constitute a drive unit that moves the under cover 12 up and down. The actuator 17 is fixed to the perimeter frame 18 as an example. Therefore, the under cover 12 is configured to move up and down relative to the perimeter frame 18 by the drive of the actuator 17, as shown by arrow A.

[0048] 2. Structure and vertical movement of the undercover 12 The structure of each of the pair of left and right undercovers 12 (structure in side view) and the vertical movement of each undercover 12 will be explained using Figure 4. Although Figure 4 only shows one of the pair of left and right undercovers 12, the other undercover 12 has the same structure and is configured to move vertically in sync with the other undercover 12.

[0049] As shown in Figure 4(a), the under cover 12 is provided such that the front portion 12a and the rear portion 12b are smoothly continuous in the front-rear direction. The rear portion 12b of the under cover 12 is a continuous portion from the connection point with the front portion 12a to the rear edge portion 12d, and has a bottom surface 12c that is parallel to the road surface when deployed. That is, the rear portion 12b of the under cover 12 is a bottom flat portion configured such that the bottom surface 12c becomes a plane (flat) parallel to the road surface when deployed.

[0050] Furthermore, the term "parallel" in the above context includes not only cases where the bottom surface 12c of the bottom flat portion (rear part) 12b of the undercover 12 is perfectly parallel to the road surface, but also cases where it is slightly inclined to the road surface at an angle (for example, 2 degrees or less). The front portion 12a of the under cover 12 is smoothly continuous with the rear portion 12b, and is composed of a smooth curved surface such that the bottom surface 12c is gradually displaced upward as it moves from the connection point with the rear portion 12b towards the vicinity of the front end 13b of the front bumper 13.

[0051] Each under cover 12 having the structure described above is configured to be able to be raised and lowered by a drive unit including an actuator 17, as described above. In the vehicle 1 according to this embodiment, the left and right pair of under covers 12 are configured to be able to change between an deployed state in which both are lowered and a retracted state in which both are raised.

[0052] As indicated by arrow B1 in Figure 4(a), the pair of left and right undercovers 12 can assume a position where they protrude below the lower edge 13a of the front bumper 13 (deployed state).

[0053] On the other hand, as shown by arrow B2 in Figure 4(b), the left and right pair of undercovers 12 can be positioned in a way that at least a portion of them is stored inside the front bumper 13 (stored state). In this embodiment, one example is a configuration in which a portion of each of the left and right pair of undercovers 12 protrudes below the lower edge 13a of the front bumper 13 in the stored state, but a configuration in which the entirety of each of the left and right pair of undercovers 12 rises above the lower edge 13a of the front bumper 13 may also be adopted.

[0054] 3. Peripheral structure of undercover 12 The surrounding structure of the under cover 12 in vehicle 1 will be explained using Figures 5 to 8. Figure 5 is a perspective view showing the under cover 12 and its surrounding structure in the deployed state, and Figure 6 is an deployed perspective view showing the under cover 12 and its surrounding structure. Figure 7 is a cross-sectional view showing the section along line VII-VII in Figure 5, and Figure 8 is a cross-sectional view showing the section along line VIII-VIII in Figure 5. Note that Figure 8 shows the under cover 12 in the retracted state. Also, Figures 5 to 8 only show one of the pair of under covers 12 and its surrounding part, but the other under cover 12 and its surrounding part have the same structure.

[0055] As shown in Figures 5 and 6, the vehicle 1 further comprises a lateral sealing member 19, a front sealing member 20, and an intermediate bracket 21 around the under cover 12. The lateral sealing member 19 is composed of a bellows-shaped membrane member and, as shown in Figure 8, is provided to airtightly seal the space between the side edge 12f of the under cover 12 and the lower side wall surface 21a of the intermediate bracket 21.

[0056] Two lateral sealing members 19 are attached to each of the left and right undercovers 12, for a total of four on the vehicle 1. As shown in Figure 6, each lateral sealing member 19 is arranged so that the bellows folds 19a extend in the front-rear direction.

[0057] Furthermore, the side edge portion 12f of the under cover 12 to which the lower part of the lateral sealing member 19 is joined is the upper end edge portion of the side wall portion 12e, which is provided to rise upward from both sides in the vehicle width direction of the rear portion 12b of the under cover 12.

[0058] As shown in Figures 5 to 7, the front sealing member 20 is a tubular member having a hollow portion, and when the under cover 12 is in the deployed state, it airtightly seals the space between the flange portion 12g of the under cover 12 and the edge portion 13c of the front bumper 13. The flange portion 12g of the under cover 12 is a flange-shaped portion that protrudes forward from the upper end of the curved portion of the front part 12a.

[0059] The intermediate bracket 21 has a rectangular frame shape in plan view and, although detailed illustration is omitted, is fixed to the perimeter frame 18. That is, the lateral sealing member 19 and the front sealing member 20 airtightly seal the space between the under cover 12 and the vehicle body when the under cover 12 is in the deployed state.

[0060] Here, as shown in Figure 7, the under cover 12 descends to a state where it elastically deforms the front sealing member 20 in the vertical direction, and then unfolds. From this point, the front sealing member 20, the under cover 12, and the front bumper 13 are in airtight contact.

[0061] Furthermore, as indicated by arrow C in Figure 7, when the under cover 12 is in the deployed state, the bottom surface 12c of the rear edge 12d of the under cover 12 and the bottom surface of the PT cover 15 are arranged so that there is no step difference in the vertical direction.

[0062] 4. Control configuration for the movement of the under cover 12 The control configuration related to the movement (up and down movement) of the under cover 12 will be explained using Figures 9 and 10.

[0063] As shown in Figure 9, the vehicle 1 further comprises an outside temperature measurement unit 22, a vehicle speed measurement unit 23, and a control unit 24. The outside temperature measurement unit 22 measures the outside temperature around the vehicle 1 and inputs the measured outside temperature information to the control unit 24.

[0064] The vehicle speed measurement unit 23 measures the driving speed (vehicle speed) of the vehicle 1 while it is in motion and inputs the measured vehicle speed information to the control unit 24.

[0065] The control unit 24 is configured with a microprocessor including an MPU / CPU, ASIC, ROM, RAM, etc., and memory. The control unit 24 executes firmware pre-stored in memory to acquire outside temperature information and vehicle speed information as above the vehicle and performs drive control of the actuators 17 (left actuator 17L, right actuator 17R).

[0066] The control unit 24 includes a reference map storage unit 241, a cover state determination unit 242, and an actuator drive command unit 243. The reference map storage unit 2411 pre-stores a reference map in which an outside temperature threshold and a vehicle speed threshold are defined as thresholds for raising / lowering the under cover 12.

[0067] As shown in Figure 10, the reference map stored in the reference map storage unit 221 defines an ambient temperature threshold Ts, which is the ambient temperature threshold for raising or lowering the undercover 12 (left undercover 12L, right undercover 12R), and a vehicle speed threshold Vs, which is the vehicle speed threshold. The ambient temperature threshold Ts and the vehicle speed threshold Vs may differ depending on the destination of the vehicle 1. In this embodiment, as an example, the ambient temperature threshold Ts is defined to be in the range of 5°C to 7°C, and the vehicle speed threshold Vs is defined to be in the range of 45 km / h to 60 km / h.

[0068] The cover state determination unit 242 determines whether the under cover 12 should be in the deployed state (lowered state) or the retracted state (upward state) based on the acquired outside temperature information and vehicle speed information, and the reference map stored in the reference map storage unit 241.

[0069] Based on the results determined by the cover state determination unit 242, the actuator drive command unit 243 issues drive commands to the left actuator 17L and the right actuator 17R in a synchronized manner.

[0070] 5. Drive control of actuator 17 performed by control unit 24 The method for controlling the drive of the actuator 17, which is performed by the control unit 24, will be explained with reference to Figure 11.

[0071] As shown in Figure 11, the control unit 24 determines whether the outside temperature T is lower than the outside temperature threshold Ts defined in the reference map (see Figure 10) based on the outside temperature information obtained from the outside temperature measurement unit 22 (step S1). If the control unit 24 determines that the outside temperature T is lower than the outside temperature threshold Ts (step S1: YES), the cover state determination unit 242 decides to put the left under cover 12L and the right under cover 12R into the retracted state, and the actuator drive command unit 243 issues an upward command to the left actuator 17L and the right actuator 17R (step S3).

[0072] On the other hand, if the control unit 24 determines that the outside temperature T is the same as or higher than the outside temperature threshold Ts (step S1: NO), it determines, based on the vehicle speed information acquired from the vehicle speed measurement unit 23, whether the vehicle speed V is lower than the vehicle speed threshold Vs defined in the reference map (see Figure 11) (step S2). If the control unit 24 determines that the vehicle speed V is lower than the vehicle speed threshold Vs (step S2: YES), the cover state determination unit 242 decides to put the left under cover 12L and the right under cover 12R into the retracted state, and the actuator drive command unit 243 issues an upward command to the left actuator 17L and the right actuator 17R (step S3).

[0073] In response, if the control unit 24 determines that the vehicle speed V is equal to or higher than the vehicle speed threshold Vs (step S2: NO), the cover state determination unit 242 determines that the left under cover 12L and the right under cover 12R should be deployed, and the actuator drive command unit 243 issues a lowering command to the left actuator 17L and the right actuator 17R (step S4). That is, in the vehicle 1 according to this embodiment, if the control unit 24 determines that the outside temperature T is equal to or higher than the outside temperature threshold Ts, and the vehicle speed V is equal to or higher than the vehicle speed threshold Vs, it issues a command to the drive unit, including the left actuator 17L and the right actuator 17R, to lower the left under cover 12L and the right under cover 12R in synchronous motion.

[0074] The control unit 24 repeatedly executes steps S1 to S4 when the vehicle 1 is in the ignition state.

[0075] 6. Effects Vehicle 1 according to this embodiment is equipped with a pair of left and right undercovers 12, each having a rear portion 12b which is a flat bottom surface. The rear portion 12b of each undercover 12L, 12R is the part that is parallel to the road surface when the undercovers 12L, 12R are deployed. Therefore, when the vehicle 1 is driven with the left and right pair of undercovers 12L, 12R each deployed, the pressure decreases as it goes towards the trailing edge 12d of the rear portion 12b. Thus, in vehicle 1 equipped with a pair of left and right undercovers 12L, 12R each having a rear portion 12b which is a flat bottom surface, when the vehicle is driven with the left and right pair of undercovers 12L, 12R each deployed, air hits the left and right front wheels 11L, 11R in a straight line in the front-rear direction, suppressing air stagnation in that area and reducing the loss of kinetic energy. This will be described in detail with reference to Figures 12 and 13. Figure 12 shows the air pressure under the undercovers 12 (left undercover 12L, right undercover 12R) and the airflow at the front underside of the vehicle in vehicle 1 according to this embodiment. Figure 13 shows the air pressure under the undercovers 92 (left undercover 92L, right undercover 92R) and the airflow at the front underside of the vehicle in a comparative example vehicle.

[0076] As shown in Figure 13(a), the vehicle in the comparative example is equipped with undercovers 92 (left undercover 92L, right undercover 92R) at the front lower part of the vehicle, which are inclined such that the gap between the bottom surface of the rear 92b and the road surface narrows as you go from front to rear. As shown in Figure 13(b), the air pressure below each undercover 92 increases as you go from front to rear. Therefore, as shown in Figure 13(c), in the vehicle in the comparative example, the air FL9 introduced from the front is deflected outward in the vehicle width direction, and the air flows diagonally outward towards the front wheels. From this, it is thought that vortices are generated near the tire treads of the front wheels, resulting in a large loss of kinetic energy.

[0077] In contrast, as shown in Figure 12(a), the vehicle 1 according to this embodiment is equipped with undercovers 12 (left undercover 12L, right undercover 12R) at the front lower part of the vehicle 1, each having a rear portion 12b that is parallel to the road surface when deployed. As shown in Figure 12(b), the air pressure below each undercover 12 decreases from front to rear. Therefore, in the vehicle 1 according to this embodiment, as shown in Figure 12(c), the air FL1 introduced from the front flows straight along the longitudinal direction and strikes each of the left and right front wheels 11 straight (in a direction substantially perpendicular to the tire tread). As a result, the generation of vortices near the front end 11a of the front wheel 11 (near the tire tread) is suppressed, and the loss of kinetic energy during driving can be kept to a minimum.

[0078] Vehicle 1 according to this embodiment does not have an under cover integrally formed in the vehicle width direction, but rather has a left under cover 12L and a right under cover 12R that are spaced apart from each other in the vehicle width direction. Therefore, compared to the case in which vehicle 1 has an under cover integrally formed in the vehicle width direction, the increase in vehicle weight and manufacturing cost is suppressed.

[0079] Furthermore, the vehicle 1 according to this embodiment is equipped with a lateral sealing member 19 that airtightly seals the space between each side edge 12f of each under cover 12L, 12R and the vehicle body (intermediate bracket 21). Therefore, when the vehicle is driven with each of the left and right under covers 12L, 12R deployed, the air being drawn out to the sides of each under cover 12L, 12R from the powertrain room above the under covers 12L, 12R (the part where the engine and drive motor, which are the driving source, are mounted) is suppressed. As a result, when the vehicle 1 is driven with each of the left and right under covers 12L, 12R deployed, the generation of vortices on the sides and rear of each under cover 12L, 12R is suppressed, and the loss of kinetic energy can be effectively reduced.

[0080] Furthermore, the vehicle 1 according to this embodiment is equipped with a drive unit (actuator 17, link mechanism 16) that moves the left and right pair of undercovers 12L and 12R up and down. Therefore, when driving on a road surface with large irregularities, or when each undercover 12L, 12R and its surrounding parts are frozen in a low-temperature environment, it is possible to drive with the undercovers 12L and 12R raised (stored) without lowering them. Thus, the vehicle 1 can suppress interference with the road surface during driving and deformation and damage to each undercover 12L, 12R and its surrounding parts due to the up and down movement of the undercovers 12L and 12R.

[0081] The interpretation of "parallel" in the above context is the same as described above.

[0082] Furthermore, since the vehicle 1 according to this embodiment is equipped with a lateral sealing member 19 made of a bellows-shaped membrane member, when the undercovers 12L and 12R are deployed, the bellows-shaped lateral sealing member 19 can be deployed in accordance with the downward movement of the undercovers 12L and 12R.

[0083] On the other hand, when the undercovers 12L and 12R are raised and stored, the bellows are folded and prevented from undesirably protruding to the sides of the undercovers 12L and 12R. Therefore, when the vehicle 1 is driven with the undercovers 12L and 12R in the stored position, damage to the side sealing members 19 by flying stones or other objects is prevented.

[0084] Furthermore, in the vehicle 1 according to this embodiment, the lateral sealing member 19 is arranged such that the fold 19a extends in the front-rear direction, which suppresses resistance to the air flowing from the front during driving. Therefore, the vehicle 1 can more effectively reduce the loss of kinetic energy during driving.

[0085] Furthermore, in this embodiment, since the upper part of the lateral sealing member 19 is fixed to the intermediate bracket 21, the lateral sealing member 19 and the under covers 12L and 12R can be pre-assembled to the intermediate bracket 21 when assembling the vehicle 1, and this assembly can then be mounted to the perimeter frame 18. Thus, the vehicle 1 can be manufactured with increased efficiency and reduced manufacturing costs.

[0086] Furthermore, since the vehicle 1 according to this embodiment is further equipped with a front sealing member 20, when the vehicle is driven with the undercovers 12L and 12R in the deployed state, the air being sucked out from between the undercovers 12L and 12R and the front bumper 13 can also be suppressed. Therefore, the vehicle 1 can suppress the generation of vortices below the front of the undercovers 12L and 12R, thereby more reliably reducing the loss of kinetic energy.

[0087] Furthermore, since the vehicle 1 according to this embodiment is equipped with a front sealing member 20 having a tubular shape, when each under cover 12L, 12R is lowered, the front sealing member 20 can be elastically deformed vertically between it and the edge portion 13c of the front bumper 13, thereby sealing without any gaps. In this case, since the front sealing member 20 has a hollow portion, it is possible to more reliably eliminate the gap between the front sealing member 20 and the under covers 12L, 12R and the front bumper 13 compared to when a solid sealing member is used.

[0088] Furthermore, in this embodiment, the vehicle 1 is provided with the left under cover 12L and the right under cover 12R arranged and shaped symmetrically with respect to the vehicle's central axis Ax1. This allows the air flowing from the front to the underside of the vehicle to flow symmetrically in the vehicle width direction. Therefore, the vehicle 1 is suitable for reducing kinetic energy loss while ensuring handling stability during driving.

[0089] Furthermore, in this embodiment, the vehicle 1 has a control unit 24 that acquires outside temperature information and vehicle speed information, and based on the acquired information (vehicle information), issues commands to raise / lower the left actuator 17L and the right actuator 17R. Therefore, when the outside temperature T is low and there is a concern that the road surface may freeze or that the undercovers 12L, 12R and the mechanisms of the surrounding parts may freeze, the left and right pair of undercovers 12L, 12R are not lowered (they are set to the retracted state) even when the vehicle speed V is high. Also, when the vehicle speed V is slow, it is presumed that the vehicle is driving in an urban area, so the undercovers 12L, 12R are not lowered (they are set to the retracted state). In this way, the vehicle 1 can raise the undercovers 12L, 12R when the outside temperature T is relatively low or when the vehicle speed V is relatively slow, thereby suppressing deformation and damage to the undercovers 12L, 12R and the surrounding parts.

[0090] On the other hand, when the outside temperature T is relatively high and the vehicle speed V is judged to be relatively high, vehicle 1 lowers the pair of left and right undercovers 12L and 12R (to the deployed state) because freezing of the road surface, undercover 12 and its surrounding parts, and urban driving are not expected. This suppresses the generation of vortices near the front ends 11a of the left and right front wheels 11L and 11R, thereby reducing the loss of kinetic energy.

[0091] As described above, the vehicle 1 according to this embodiment can reduce kinetic energy loss by raising the undercovers 12L and 12R to suppress deformation and damage to the undercovers 12L and 12R and their surrounding parts during driving, and by lowering the undercovers 12L and 12R to suppress the occurrence of stagnation in airflow near the front ends 11a of the left and right front wheels 11L and 11R.

[0092] [Differentiation] In the above embodiment, the left under cover 12L and the right under cover 12R are arranged in a symmetrical relationship with respect to the vehicle's central axis Ax1 and have a symmetrical shape. However, in the present invention, they do not need to be symmetrical within the range of manufacturing tolerances.

[0093] Furthermore, although the above embodiment includes a PT cover 15 in addition to the under cover 12, the present invention does not necessarily require the inclusion of a PT cover 15.

[0094] Furthermore, although the above embodiment includes a lateral sealing member 19 made of a bellows-shaped membrane member, the present invention may also include a lateral sealing member 19 made of other materials. For example, the lateral sealing member may be made of a plate-shaped elastomer or sponge.

[0095] Furthermore, although the above embodiment employs a configuration in which the upper part of the lateral sealing member 19 is fixed to the intermediate bracket 21, the present invention is not limited thereto. For example, the upper part of the lateral sealing member 19 may be directly fixed to the perimeter frame 18, or it may be fixed to other parts of the vehicle body (for example, the front side member or the front cross member).

[0096] Furthermore, although the above embodiment includes a front sealing member 20 made of a tubular member having a hollow portion, the present invention does not necessarily require the inclusion of a front sealing member 20. Also, the members constituting the front sealing member 20 are not limited to tubular members, and plate-shaped members made of elastomer or members made of sponge can also be used.

[0097] Furthermore, in the above embodiment, the control unit 24 acquires outside temperature information and vehicle speed information as being above the vehicle and decides whether to keep the under cover 12 in the retracted state or in the deployed state based on this information, but the present invention is not limited thereto. For example, navigation information may be acquired instead of vehicle speed information. This makes it possible to determine whether to raise or lower the under cover 12 based on the road surface conditions that have been registered in advance as navigation information.

[0098] Furthermore, a system (for example, a laser measuring instrument) that monitors the road surface conditions in front of vehicle 1 can be used as a basis for judging the road surface conditions.

[0099] Furthermore, the vehicle according to the present invention does not necessarily have to be equipped with a control unit 24. Specifically, the driver operating the vehicle 1 may determine the environment of the road surface and driving route in which they intend to travel and issue a command to raise or lower the under cover 12.

[0100] Furthermore, although the above embodiment employs a structure in which the actuators 17L and 17R are fixed to the perimeter frame 18, the present invention also allows the actuators 17L and 17R to be fixed to other parts of the vehicle body (for example, the front side member or the front cross member). [Explanation of Symbols]

[0101] 1 vehicle 11L left front wheel 11R Right front wheel 12 Undercover 12L Left Undercover 12R Right Undercover 17 Actuator (Drive Unit) 17L Left Actuator 17R Right Actuator 18 Perimeter Frame 19. Lateral sealing member 20 Front sealing member 21 Intermediate bracket 22 Outdoor temperature measurement unit 23. Vehicle speed measurement unit 24 Control Unit

Claims

1. At the front of the vehicle, a pair of front wheels are positioned at both ends in the width direction of the vehicle, The portion of the vehicle in the longitudinal direction from near the front ends of the pair of left and right front wheels forward, the left and right undercovers being spaced apart from each other between the left and right front wheels in the vehicle width direction, and each being provided so as to cover the bottom surface of the vehicle body, A drive unit that moves the pair of left and right undercovers up and down, When the pair of left and right undercovers are in an extended state, lowered by the drive unit, a lateral sealing member is provided to airtightly seal the space between each side edge of the pair of left and right undercovers and the vehicle body, Equipped with, Each of the pair of left and right undercovers, when in the deployed state, has a flat bottom portion in the forward part from the rear edge, where the bottom surface is parallel to the road surface. vehicle.

2. The aforementioned lateral sealing member is a bellows-shaped membrane member. The vehicle according to claim 1.

3. The aforementioned bellows-shaped membrane member is provided with folds that extend in the front-rear direction of the vehicle. The vehicle according to claim 2.

4. The vehicle body is equipped with an intermediate bracket fixed to the perimeter frame, Each of the aforementioned lateral sealing members has its upper part fixed to the intermediate bracket. The vehicle according to claim 1.

5. A front bumper is provided positioned in front of the aforementioned pair of left and right front wheels and extending in the width direction at the front end of the vehicle, In the deployed state, a front sealing member is provided to airtightly seal the space between the front edges of the pair of left and right undercovers and the front bumper, Furthermore, The vehicle according to claim 1.

6. The aforementioned front sealing member has a tubular shape with a hollow portion in its cross-section. The vehicle according to claim 5.

7. Assuming a vehicle center axis that passes through the center in the width direction and extends in the longitudinal direction of the vehicle, The pair of left and right undercovers are arranged symmetrically with respect to the vehicle's central axis and have shapes that are symmetrical to each other. A vehicle according to any one of claims 1 to 6.

8. An ambient temperature measuring unit that measures the ambient temperature, A vehicle speed measuring unit for measuring the vehicle's speed, A control unit that acquires outside temperature information from the outside temperature measurement unit and vehicle speed information from the vehicle speed measurement unit, and based on the acquired information, issues a command to the drive unit to raise or lower the pair of left and right undercovers, Furthermore, A vehicle according to any one of claims 1 to 6.

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