JP7341908B2 - undercover - Google Patents

Description

The present invention relates to an undercover provided under the floor of a vehicle to reduce air resistance.

As shown in FIG. 13, an undercover 1 is provided under the floor of the vehicle in order to reduce the resistance of air flowing under the vehicle floor by making the entire underfloor area of the vehicle nearly flat.

However, as shown in FIG. 14, since front tires 101 and rear tires 102 are disposed at the outer ends in the width direction of the vehicle, the air flowing under the floor of the vehicle is blocked by the tires 100. Therefore, the air flow in the vicinity of the tire 100 (at the outer end of the vehicle in the width direction and its vicinity) is smaller than in the center part in the width direction of the vehicle, and the air flow is concentrated in the center part in the width direction of the vehicle. As a result, there is room for improvement in terms of improving the aerodynamic performance of the vehicle by increasing the flow rate of air flowing from under the vehicle floor to the rear of the vehicle (exit flow rate).

As shown in FIG. 15, JP 2016-222152A discloses a main cover (rear undercover) 1a having an inter-tire portion 1a-1 located between left and right tires 100, which is tilted rearward and upward of the vehicle. This disclosure discloses a technique in which the height of the lower surface of the inter-tire portion 1a-1 is higher than the height of the lower surface of the front cover (floor undercover) 1b located on the front side of the vehicle of the main cover 1a. According to this technique, the cross-sectional area of the flow path between the tires 100 can be increased compared to the case where the inter-tire portion 1a-1 has the same lower surface height as the front cover 1b. It is thought that the flow rate of air can be increased, and as a result, the flow rate of air flowing from under the vehicle floor to the rear of the vehicle can be increased.

However, even with the technique disclosed in the above publication, since the inter-tire portion 1a-1 is tilted rearward and upward of the vehicle evenly over the entire widthwise direction of the vehicle, the flow is concentrated toward the center portion of the vehicle in the widthwise direction. The problem of storage still remains.

Japanese Patent Application Publication No. 2016-222152

An object of the present invention is to provide an undercover that can increase the flow rate near the tire compared to the conventional one.

The present invention that achieves the above object is as follows.
(1) A main cover having an inter-tire section located between the left and right tires;
a front cover located on the vehicle front side of the main cover;
, wherein the lower surface height of the inter-tire portion of the main cover is higher than the lower surface height of the front cover,
The inter-tire portion includes a central portion between the tires including a central portion in the vehicle width direction of the inter-tire portion, and an outer end portion of the inter-tire portion located on both outer sides in the vehicle width direction of the central portion between the tires. and an outer inter-tire portion including;
The undercover is configured such that the outer side portion between the tires has a higher lower surface height than the center portion between the tires.
(2) The lower surface of the area between the tires has a horizontal portion extending in a straight line orthogonal to the vertical direction of the vehicle in a cross-sectional view orthogonal to the vehicle width direction, at least at the intermediate portion of the area between the tires in the longitudinal direction of the vehicle. The undercover described in (1).
(3) The main cover has a front part of the main cover located on the front side of the vehicle between the tires, and the lower surface of the front part of the main cover is inclined toward the rear side of the vehicle and above the vehicle. ) or the undercover described in (2).
(4) The undercover according to any one of (1) to (3), wherein the main cover has a one-piece configuration.
(5) further comprising a rear cover located on the rear side of the vehicle of the main cover;
Any one of (1) to (4), wherein the rear end of the lower surface of the inter-tire portion is inclined toward the rear of the vehicle and downward of the vehicle toward the front end of the lower surface of the rear cover. Undercover mentioned in one.
(6) The undercover according to any one of (1) to (5), wherein the inter-tire portion is provided between at least one of the left and right front tires and between the left and right rear tires.

In the undercovers (1) to (6) above, the lower surface height of the portion between the tires is higher than the lower surface height of the front cover. Therefore, compared to a case where the lower surface height between the tires is the same as or lower than the lower surface height of the front cover, it is possible to increase the cross-sectional area of the flow path between the tires, and the flow rate of air flowing under the vehicle floor. can be increased.

Further, the outer side portion between the tires has a higher lower surface height than the center portion between the tires. Therefore, compared to a case where the lower surface height of the outer part between the tires is the same as or lower than the lower surface height of the central part between the tires, You can make it bigger. As a result, it is possible to increase the flow rate of air flowing through the outer portion between the tires, and it is possible to alleviate the concentration of air flow toward the center portion in the width direction of the vehicle. As a result, the amount of air flowing from under the vehicle floor to the rear of the vehicle (exit flow rate) can be increased, and the aerodynamic performance of the vehicle can be improved. Furthermore, since the flow rate of air flowing through the outer side between the tires can be increased, turbulence in the flow behind the tires can be reduced, and the aerodynamic performance of the vehicle can also be improved in this respect.

In the undercover of (2) above, the lower surface of the space between the tires has a horizontal portion that extends in a straight line perpendicular to the vertical direction of the vehicle in a cross-sectional view perpendicular to the vehicle width direction, at least in the middle part of the space between the tires in the longitudinal direction of the vehicle. have. Therefore, compared to a case where the lower surface of the space between the tires slopes toward the rear of the vehicle and above the vehicle throughout the longitudinal direction of the vehicle, the cross-sectional area of the flow path between the tires can be increased, and the flow rate of air flowing under the vehicle floor increases. can be increased.

In the undercover (3) above, the lower surface of the front part of the main cover is inclined toward the rear of the vehicle and above the vehicle. Therefore, even if the lower surface height of the space between the tires is higher than that of the front cover, air flowing along the front cover can flow along the space between the tires without being separated.

In the undercover (4) above, since the main cover is composed of one part, the number of parts can be reduced and it is advantageous in terms of cost compared to the case where the main cover is composed of multiple parts.

In the undercover of (5) above, the vehicle rear side end of the lower surface of the inter-tire portion is inclined toward the vehicle front side end of the lower surface of the rear cover toward the vehicle rear side and vehicle downward direction. Therefore, even if the lower surface height of the inter-tire area is higher than that of the rear cover, the air flowing along the inter-tire area can flow smoothly along the rear cover.

FIG. 1 is a perspective view of a vehicle provided with an undercover according to an embodiment of the present invention, as seen diagonally from below. 2 is an enlarged view of section E in FIG. 1. FIG. FIG. 2 is a bottom view of a vehicle provided with an undercover according to an embodiment of the present invention. FIG. 4 is a cross-sectional view taken along the line AA in FIG. 3. 4 is a sectional view taken along line BB in FIG. 3. FIG. 4 is a sectional view taken along the line CC in FIG. 3. FIG. FIG. 4 is a cross-sectional view taken along the line BB in FIG. 3 and a partially enlarged view of a portion D, which is a connecting portion between the component parts, in a case where the main cover has a plurality of parts in the longitudinal direction of the vehicle. FIG. 4 is a cross-sectional view taken along the line CC in FIG. 3 when the main cover is composed of multiple parts in the vehicle width direction. 8 is a partially enlarged view showing a modification of section D in FIG. 7. FIG. FIG. 3 is a diagram showing the total pressure distribution of air flowing under the vehicle floor in a vehicle provided with an undercover according to an embodiment of the present invention. In order to show the superiority of the undercover according to the embodiment of the present invention, the rear tire rear disturbance range of the vehicle provided with the undercover shown in FIG. 14 is also shown by a dashed dotted line. FIG. 3 is a comparison diagram of the outlet flow rate flowing from the underfloor of the vehicle toward the rear of the vehicle in a vehicle (a) in which the undercover according to the embodiment of the present invention is provided and a vehicle (b) in which the entire underfloor of the vehicle is flat. A vehicle (a) in which the undercover of the embodiment of the present invention is installed, a vehicle (b) in which the entire underfloor of the vehicle is flat, and a vehicle (a) in which the underside height is higher than in (b); ) is a comparison diagram of the outlet flow rate flowing from under the vehicle floor to the rear of the vehicle with a vehicle (c) in which the lower surface height is raised uniformly in the vehicle width direction so as to have the same flow path cross-sectional area as in (c). FIG. 1 is a perspective view of a conventional vehicle in which the entire underfloor of the vehicle is flat, as viewed diagonally from below. FIG. 2 is a diagram showing the total pressure distribution of air flowing under the vehicle floor in a vehicle provided with a conventional undercover. FIG. 2 is a partial sectional view of a vehicle equipped with a conventional undercover, in which the main cover of the undercover is inclined toward the rear of the vehicle and upward of the vehicle.

Below, an undercover 10 according to an embodiment of the present invention will be described with reference to the drawings. In the figure, UP indicates the upper side of the vehicle, FR indicates the front of the vehicle, and OUT indicates the outer side in the vehicle width direction.

As shown in FIG. 1, an undercover 10 according to an embodiment of the present invention is provided under the floor of a vehicle V to reduce air resistance. Although the undercover 10 is not particularly limited, it is desirable that the undercover 10 be provided on the entire surface under the floor of the vehicle V. This is because the air resistance reduction effect of the undercover 10 can be obtained over the entire area under the floor of the vehicle V.

The undercover 10 is made of resin, for example. The undercover 10 includes a main cover 20, a front cover 30 on the front side of the main cover 20 in the vehicle, and a rear cover 40 on the rear side of the main cover 20 in the vehicle.

The main cover 20 may have a one-piece structure or a multi-piece structure. When the main cover 20 has a plurality of parts, the components are connected and fixed to each other. When the main cover 20 has a plurality of parts, the main cover 20 may have a plurality of parts in the longitudinal direction of the vehicle (FIG. 7), or may have a plurality of parts in the width direction of the vehicle (FIG. 8). In addition, when the main cover 20 has a multi-component configuration, as shown in FIG. It is desirable that an extension part 20a extending in a direction in which the distance from each other becomes closer is formed on at least one of the parts.

As shown in FIG. 2, the main cover 20 includes an inter-tire section 21 located between the left and right tires 100, and a main cover front section 22 located on the vehicle front side of the inter-tire section 21.

The inter-tire portion 21 is provided (located) between the left and right tires 100. The tire 100 may be the front tire 101 or the rear tire 102 of the vehicle, or may be both the front tire 101 and the rear tire 102. That is, the inter-tire portion 21 may be provided between at least one of the left and right front tires 101 and between the left and right rear tires 102. In the embodiments and illustrated examples of the present invention, a case where the tire 100 is a rear tire 102 and the inter-tire portion 21 is provided only between the left and right rear tires 102 will be described as an example.

As shown in FIGS. 4 and 5, above the inter-tire portion 21, a vehicle body side component M consisting of a vehicle body or a component mounted on the vehicle body is disposed. The vehicle body side parts M are, for example, a rear motor, a rear suspension member, etc. The lower surface height of the inter-tire portion 21 is higher than the lower surface height of the front cover 30. Therefore, the flow path cross-sectional area (cross-sectional area perpendicular to the longitudinal direction of the vehicle) of the air flowing under the vehicle floor is larger under the inter-tire portion 21 than under the front cover 30. The height of the lower surface of the inter-tire portion 21 is set high within the limit of not interfering with the vehicle body side part M.

As shown in FIG. 2, the inter-tire portion 21 includes an inter-tire central portion 21a including a central portion (center portion) P in the vehicle width direction of the inter-tire portion 21, and both outer sides of the inter-tire central portion 21a in the vehicle width direction. and an inter-tire outer side portion 21b that includes an outer end portion of the inter-tire portion 21 in the vehicle width direction.

The lower surface of the inter-tire central portion 21a has a horizontal portion 21a1 extending in a straight line perpendicular to the vehicle vertical direction in a cross-sectional view perpendicular to the vehicle width direction, at least at the intermediate portion of the inter-tire portion 21 in the longitudinal direction of the vehicle. . The vehicle front end of the horizontal portion 21a1 is directly connected to the vehicle rear end of the main cover front portion 22. The vehicle rear end of the horizontal portion 21a1 is connected to the rear cover 40 via an inclined portion 21a2 that slopes toward the vehicle rear and vehicle downward toward the vehicle front end of the lower surface of the rear cover 40.

The inter-tire central portion 21a may have a lower surface with a uniform height over the entire area of the inter-tire central portion 21a in the vehicle width direction, and both outer side portions 21a3 of the inter-tire central portion 21a in the vehicle width direction are The lower surface height may be higher than the center portion in the width direction in a stepped or inclined manner.

The inter-tire outer side portion 21b has a higher lower surface height than the inter-tire central portion 21a. The lower surface of the inter-tire outer part 21b has a horizontal part 21b1 extending in a straight line perpendicular to the vehicle vertical direction in a cross-sectional view perpendicular to the vehicle width direction, at least at the intermediate part of the inter-tire part 21 in the longitudinal direction of the vehicle. . Because the inter-tire outer side portion 21b has a horizontal portion 21b1 at least at the intermediate portion in the longitudinal direction of the vehicle, and as described above, the inter-tire central portion 21a also has the horizontal portion 21a1 at least at the intermediate portion in the longitudinal direction of the vehicle. The lower surface of the inter-tire portion 21 has horizontal portions 21b1 and 21a1 at least in the intermediate portion of the inter-tire portion 21 in the longitudinal direction of the vehicle.

The vehicle front side end of the horizontal portion 21b1 of the inter-tire outer side portion 21b is connected to the main cover via a front side inclined portion 21b2 that is inclined toward the vehicle front side and vehicle downward direction toward the vehicle rear side end of the lower surface of the main cover front portion 22. It continues to the front part 22. The vehicle rear side end portion of the horizontal portion 21b1 of the inter-tire outer side portion 21b is connected to the rear side through the rear side inclined portion 21b3 which is inclined toward the vehicle front side end of the lower surface of the rear cover 40 toward the vehicle rear side and the vehicle downward direction. It continues to the side cover 40. A portion of the rear inclined portion 21b3 is also continuous with the inclined portion 21a2 of the inter-tire center portion 21a.

The center end in the vehicle width direction of the horizontal portion 21b1 of the inter-tire outer portion 21b is an inner inclined portion that is inclined toward the center in the vehicle width direction and downwardly toward the outer end in the vehicle width direction of the lower surface of the inter-tire center portion 21a. It is connected to the inter-tire center portion 21a via 21b4. As shown in FIG. 6, the outer end in the vehicle width direction of the horizontal portion 21b1 of the inter-tire outer portion 21b is connected to a fender liner 110 that forms a part of the wheel house of the vehicle.

As shown in FIG. 2, the main cover front part 22 is located on the vehicle front side of the inter-tire area 21 and on the vehicle rear side of the front cover 30, and connects the inter-tire area 21 and the front cover 30 in the longitudinal direction of the vehicle. . The lower surface of the main cover front portion 22 is inclined toward the rear of the vehicle and upward of the vehicle.

As shown in FIG. 4, the front cover 30 is provided extending from the vehicle front end of the main cover front section 22 toward the vehicle front. The front cover 30 may be referred to as a floor undercover, and is provided from the front end of the main cover 22 to the rear end of the vehicle between the front tires 101 or its vicinity. The lower surface of the front cover 30 is flat over the entire surface (including almost the entire surface) of the front cover 30. First and second engine undercovers 50 and 51 are provided on the vehicle front side of the front cover 30. A vehicle front side end portion of the first engine undercover 50 is connected to a lower end portion of the front bumper 120 of the vehicle.

The rear cover 40 is provided extending from the vehicle rear end of the main cover 20 toward the vehicle rear side. The rear cover 40 may be referred to as a rear undercover, and is provided from the vehicle rear end of the main cover 20 to the vehicle rear end. The lower surface of the rear cover 40 is an inclined surface that slopes toward the rear of the vehicle and above the vehicle over the entire surface (including almost the entire surface) of the rear cover 40. A vehicle rear end portion of the rear cover 40 is connected to a lower end portion of a rear bumper 130 of the vehicle.

Next, the functions and effects of the embodiments of the present invention will be explained.

(A) As shown in FIG. 2, the lower surface height of the inter-tire portion 21 is higher than the lower surface height of the front cover 30. Therefore, compared to the case where the lower surface height of the inter-tire section 21 is the same as or lower than the lower surface height of the front cover 30, the cross-sectional area of the flow path in the inter-tire section 21 can be increased, and the flow under the vehicle floor can be increased. Air flow rate can be increased.

(B) The lower surface height of the inter-tire outer portion 21b is higher than that of the inter-tire central portion 21a. Therefore, compared to the case where the lower surface height of the inter-tire outer portion 21b is the same as or lower than the lower surface height of the inter-tire central portion 21a, the flow path cross-sectional area of the inter-tire outer portion 21b is reduced to the flow path of the inter-tire central portion 21a. It can be made larger than the cross-sectional area. As a result, the flow rate of air flowing through the inter-tire outer side portion 21b can be increased, and concentration of the air toward the center portion in the width direction of the vehicle can be alleviated. As a result, the amount of air flowing from under the vehicle floor to the rear of the vehicle (exit flow rate) can be increased, and the aerodynamic performance of the vehicle can be improved. Furthermore, since the flow rate of air flowing through the inter-tire outer side portion 21b can be increased, turbulence in the flow behind the tires can be reduced, and the aerodynamic performance of the vehicle can also be improved in this respect.

(B1) FIG. 10 is a diagram showing the total pressure distribution of the air flowing under the vehicle floor in the vehicle V having the undercover 10 of the embodiment of the present invention, obtained through an experiment. The dotted line on the rear side of the rear tire in FIG. 10 indicates the turbulence range of the air flow on the rear side of the rear tire 102 (rear tire rearward turbulence range). In order to show the superiority of the undercover 10 according to the embodiment of the present invention, the rear tire rear disturbance range of a vehicle provided with the fully flat conventional undercover 1 shown in FIG. 14 is also shown by a dashed-dotted line.
From FIG. 10, the amount of air flowing in the inter-tire area 21 between the rear tires 102 increases in the vicinity of the tires compared to the conventional case (FIG. 14), and the flow concentrates toward the center in the width direction of the vehicle. Things had been eased. Furthermore, since the amount of air flowing near the tire increases, the flow disturbance behind the tire can be reduced in the embodiment of the present invention, as shown by the dotted line in FIG. 10, compared to the conventional system (dotted chain line). Specifically, referring to FIG. 11, according to the undercover 10 according to the embodiment of the present invention (FIG. 11(a)), compared to the fully flat conventional undercover 1 (FIG. 11(b)), It was possible to increase the flow rate of air flowing from under the vehicle floor to the rear of the vehicle (exit flow rate) by approximately 2%.

(B2) FIG. 12 shows a vehicle (a) in which the undercover 10 of the embodiment of the present invention is installed, a vehicle (b) in which the entire underfloor of the vehicle is completely flat, and a vehicle ( Although the lower surface height is higher than that of vehicle (b), the lower surface height is raised uniformly in the vehicle width direction so that the cross-sectional area of the flow path is the same as vehicle (a). It is a comparison diagram of the outlet flow rate flowing from under the vehicle floor to the rear of the vehicle.
As can be seen from FIG. 12, the outlet flow rate was increased in both vehicles (a) and (c) compared to the fully flat vehicle (b). Furthermore, compared to the vehicle (c) in which the height of the lower surface is uniformly raised, the outlet flow rate is further increased in the vehicle (a) having the undercover 10 according to the embodiment of the present invention, which has a three-dimensional shape and has a raised lower surface height. Ta.
From this, it is possible to increase the outlet flow rate by uniformly raising the lower surface height of the inter-tire section 21, but as in the embodiment of the present invention, the outer inter-tire section 21b is larger than the inter-tire central section 21a. It can be seen that the outlet flow rate can be further increased by increasing the height of the bottom surface.

(C) As shown in FIG. 2, the lower surface of the inter-tire portion 21 is formed in a straight line perpendicular to the vehicle vertical direction in a cross-sectional view perpendicular to the vehicle width direction, at least at the intermediate portion of the inter-tire portion 21 in the longitudinal direction of the vehicle. It has extending horizontal portions 21a1 and 21b1. Therefore, compared to the case where the lower surface of the tire-to-tire part 21 is inclined toward the rear side and upward of the vehicle throughout the longitudinal direction of the vehicle, the cross-sectional area of the flow path in the tire-to-tire part 21 can be increased, and the air flowing under the vehicle floor can be increased. The flow rate can be increased.

(D) The lower surface of the main cover front portion 22 is inclined toward the rear side of the vehicle and above the vehicle. Therefore, even if the lower surface height of the inter-tire section 21 is higher than that of the front cover 30, the air flowing along the front cover 30 can be allowed to flow along the inter-tire section 21 without being separated. can.

(E) Since the main cover 20 is composed of one part, the number of parts can be reduced, which is advantageous in terms of cost, compared to the case where the main cover 20 is composed of multiple parts.

(F) The vehicle rear end of the lower surface of the inter-tire portion 21 is inclined toward the vehicle front end of the lower surface of the rear cover 40 toward the vehicle rear side and vehicle downward. Therefore, even if the lower surface height of the inter-tire area 21 is higher than the vehicle front end of the rear cover 40, air flowing along the inter-tire area 21 can be smoothly transferred to the rear cover 40. It can be flowed along.

10 Undercover 20 Main cover 20a Extension part 21 Part between tires 21a Central part between tires 21a1 Horizontal part 21a2 of central part between tires Slanted part 21a3 of central part between tires Both outer sides in the vehicle width direction of central part between tires 21b Between tires Outside part 21b1 Horizontal part 21b2 of the outside part between tires 21b3 Front slope part of the outside part between tires 21b4 Rear side slope part 21b4 of the outside part between tires 22 Main cover front part 30 Front cover 40 Rear cover 50 First engine cover 51 Second engine cover 100 Tire 101 Front tire 102 Rear tire 110 Fender liner 120 Front bumper 130 Rear bumper M Vehicle side parts V Vehicle

Claims (5)

a main cover having an inter-tire portion located between the left and right tires;
a front cover located on the vehicle front side of the main cover;
The undercover has a lower surface height of a portion between the tires of the main cover that is higher than a lower surface height of the front cover over the entire region between the tires in the vehicle width direction ,
The inter-tire portion includes a central portion between the tires including a central portion in the vehicle width direction of the inter-tire portion, and an outer end portion of the inter-tire portion located on both outer sides in the vehicle width direction of the central portion between the tires. and an outer inter-tire portion including;
The outer part between the tires has a lower surface height higher than the center part between the tires,
The main cover has a main cover front part located on the front side of the vehicle between the tires, and the lower surface of the main cover front part is located on the rear side of the vehicle and on the vehicle widthwise entire area of the main cover front part. Undercover , sloping upwards . The lower surface of the inter-tire portion has a horizontal portion extending in a straight line perpendicular to the vehicle vertical direction in a cross-sectional view perpendicular to the vehicle width direction, at least at an intermediate portion of the inter-tire portion in the longitudinal direction of the vehicle. The undercover described in item 1. The undercover according to claim 1 or 2 , wherein the main cover has a one-piece construction . further comprising a rear cover located on the vehicle rear side of the main cover,
Any one of claims 1 to 3, wherein the rear end of the lower surface of the inter-tire portion is inclined toward the rear of the vehicle and downward of the vehicle toward the front end of the lower surface of the rear cover. The undercover described in item 1. The inter-tire portion is provided between at least one of the left and right front tires and between the left and right rear tires.The undercover according to any one of claims 1 to 4.

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