CN107856619B

CN107856619B - Vehicle undercover structure

Info

Publication number: CN107856619B
Application number: CN201710731694.XA
Authority: CN
Inventors: 武田数马
Original assignee: Suzuki Motor Corp
Current assignee: Suzuki Motor Corp
Priority date: 2016-09-21
Filing date: 2017-08-23
Publication date: 2021-02-05
Anticipated expiration: 2037-08-23
Also published as: FR3056184A1; FR3056184B1; JP2018047779A; CN107856619A; JP6798209B2; DE102017119367A1

Abstract

Provided is a vehicle body undercover structure that is disposed below an engine/power unit chamber and that is capable of increasing the flow rate of air passing through the engine/power unit chamber and improving the cooling performance of a radiator while reducing air resistance. A vehicle under-hood structure having one structure according to the present invention is disposed below an engine room (100b) of a vehicle (100a), and a radiator (102), an engine (104), and a suspension frame (106) are disposed in the engine room (100b) in this order from the front of the vehicle. The vehicle body undercover structure for a vehicle includes: an under cover (110) that extends from the lower end of a front bumper (108) of the vehicle to the rear of the suspension frame (106) and that forms the lower surface of the engine compartment (100 b); and an opening (120) that is formed in the under cover (100) at a position that is located behind the vehicle at the center (105) of the engine (104) and in front of the suspension frame (106) in the vehicle.

Description

Vehicle undercover structure

Technical Field

The present invention relates to a vehicle body undercover structure for a vehicle.

Background

The engine/power unit is disposed in an engine/power unit chamber of a vehicle such as an automobile, and a bottom wall of the engine/power unit chamber is constituted by an under cover such as an under cover disclosed in patent document 1.

A radiator for cooling the engine/power unit is also disposed in the engine/power unit compartment. To improve the cooling performance of the radiator, the flow rate of air passing through the engine/power unit compartment must be increased. In view of this, in patent document 1, the cooling air flow rate can be maintained by changing the shape of the under cover in accordance with the height of the floor.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2012-136062

Disclosure of Invention

Problems to be solved by the invention

However, as also disclosed in patent document 1, a vehicle body structural member such as a cross member is generally disposed in the engine/power unit room. According to the configuration in patent document 1, the cooling air flows efficiently toward the rear of the vehicle above the engine/power unit, but the flow of the cooling air below the engine/power unit is blocked by the cross member. For this reason, air is liable to stagnate in the engine/power unit chamber, and further improvement is required in order to increase the flow rate of air passing through the engine/power unit chamber.

In view of the problem, an object of the present invention is to provide a vehicle body undercover structure capable of increasing the flow rate of air passing through an engine/power unit chamber and improving the cooling performance of a radiator.

Means for solving the problems

In order to solve the problem, a representative structure of an under cover structure for a vehicle according to the present invention is an under cover structure for a vehicle disposed below an engine/power unit chamber of a vehicle in which a radiator, an engine/power unit, and a suspension frame are disposed in this order from a front of the vehicle, the under cover structure for a vehicle including: an under cover that extends rearward of the suspension frame from a lower end of a front bumper of the vehicle and that constitutes a lower surface of the engine/power unit chamber; and an opening portion formed in the under cover at a position that is located at the vehicle rear of the center of the engine/power unit and at the vehicle front of the suspension frame.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, the following vehicle undercover structure can be provided: which can increase the flow rate of air passing through the engine/power unit chamber and can improve the cooling performance of the radiator.

Drawings

Fig. 1 is a diagram illustrating an embodiment of an under cover structure for a vehicle according to the present invention.

Fig. 2 is a view showing a state in which the under cover structure in fig. 1 is viewed from below.

Fig. 3 is a diagram illustrating an effect of the under cover structure according to the embodiment.

Detailed Description

A vehicle undercover structure according to this embodiment is a vehicle undercover structure that is disposed below an engine/power unit chamber of a vehicle in which a radiator, an engine/power unit, and a suspension frame are disposed in this order from a vehicle front side, and includes: an under cover that extends rearward of the suspension frame from a lower end of a front bumper of the vehicle and that constitutes a lower surface of the engine/power unit chamber; and an opening portion formed in the under cover at a position that is located at the vehicle rear of the center of the engine/power unit and at the vehicle front of the suspension frame.

According to the above configuration, air passing below the engine/power unit can be discharged from the opening portion without being blocked by the suspension frame. Therefore, the air can be restrained from being trapped in the engine/power unit chamber, and the flow rate of the air introduced into the engine/power unit chamber can be increased, so that the cooling performance of the radiator can be improved.

Preferably, the under cover includes an inclined portion that extends rearward of the vehicle from the front bumper and is inclined downward, and a horizontal portion that is continuous with a rear end of the inclined portion, extends rearward of the vehicle from the rear end, is substantially horizontal, and the opening portion is disposed in the horizontal portion. According to this configuration, the air flowing along the inclined surface below the engine/power unit in the engine/power unit chamber can be efficiently discharged from the opening portion.

Preferably, the horizontal part includes: a front-side horizontal portion located between a rear end of the inclined portion and the opening portion, and a rear-side horizontal portion located behind the opening portion. By providing the front-side horizontal region as in the above configuration, the negative pressure at the front surface of the under cover increases, and thus the air resistance can be reduced. In addition, the provision of the rear horizontal region increases the negative pressure, and thus improves the effect of pulling air through the engine/power unit compartment. Therefore, the air pressure can be reduced, and the heat in the engine/power unit chamber can be smoothly discharged to the outside of the vehicle.

Preferably, the under cover includes a tube portion that extends from an edge of the horizontal portion on the vehicle rear side of the opening portion toward the vehicle front side and is inclined upward, and an upper end of the tube portion is located above a lower end of the suspension frame or at the same height as the lower end. According to this structure, the air flowing to the suspension frame can be quickly discharged to the outside of the vehicle before the air reaches the suspension frame.

[ embodiment ]

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Unless otherwise specifically stated, dimensions, materials, other specific numerical values, and the like in the present embodiment are merely illustrative examples for facilitating understanding of the present invention, and are not intended to limit the present invention. Note that the same reference numerals have been given to elements having substantially the same function and configuration in the present specification and the drawings so as to omit duplicated explanation, and elements not directly related to the present invention have been omitted from the drawings and the explanation.

Fig. 1 is a diagram illustrating an embodiment of an under cover structure for a vehicle (hereinafter referred to as an under cover structure 100) according to the present invention. For ease of understanding, the flow of air in the engine room 100b is indicated by a dotted arrow in fig. 1. In addition, in all the drawings of the present application, reference numeral U, D, F, R denotes the up, down, front, and rear directions of the vehicle, respectively.

As shown in fig. 1, in an under cover structure 100 of the present embodiment, a radiator 102, an engine 104, and a suspension frame 106 are disposed in the interior of an engine room 100b of a vehicle 100a (not all shown) in this order from the front of the vehicle.

The front surface of the vehicle is constituted by a front bumper 108 and a front grille 108a attached to the front bumper. The air passes through the front grill 108a and is introduced into the engine room 100 b. The air introduced into the engine room 100b passes through the radiator 102, thereby cooling the cooling water in the radiator 102. The suspension frame 106 is a vehicle body structural member that supports a suspension arm (not shown) on which a wheel located on the vehicle width direction outer side is supported.

An under cover 110 constituting the lower surface of the engine room 100b is disposed below the engine 104. The under cover 110 is joined to a lower end of a front bumper 108 of the vehicle 100a, and extends rearward of the suspension frame 106 from the lower end.

The vehicle undercover structure 100 of the present embodiment is characterized in that an opening 120 is formed in the undercover 110 at a position located rearward of the center 105 of the engine 104 in the vehicle and forward of the suspension frame 106 in the vehicle. As shown in fig. 1, the center 105 represents a geometric center, that is, a center in the vehicle front-rear direction of the engine 104. Therefore, the air introduced into the engine room 100b and passing under the engine 104 during traveling is discharged from the opening portion 120 disposed at the center 105 of the engine 104 in the rear of the vehicle.

Since the opening portion 120 is disposed in the vehicle front of the suspension frame 106, air that has passed under the engine 104 at that time is discharged from the opening portion 120 without being blocked by the suspension frame 106. Therefore, stagnation of air in the engine room 100b can be suppressed, and the flow rate of air passing through the engine room 100b can be increased, thus improving the cooling performance of the radiator 102.

Further, as described above, since the air in the engine room 100b is discharged from the opening 120, the air pressure behind the engine 104 in the engine room 100b can be reduced. Therefore, the air in the engine room 100b more easily escapes to the rear of the vehicle. Therefore, this can increase the amount of air introduced into the engine room 100b, and thus can increase the amount of air supplied to the radiator 102. Therefore, the cooling performance of the radiator 102 can be further improved.

The following phenomena have been confirmed: if the flow rate of air flowing on the vehicle lower side is high, the pressure near a rear door (not shown) decreases when the air is discharged from the rear of the vehicle, and the air resistance increases. In order to solve this phenomenon, in the vehicle undercover structure 100 of the present embodiment, when air flows from the vehicle front to the vehicle lower side along the undercover 110, the air flowing at a high flow velocity under the floor interacts with a slow air flow discharged from the engine room through the opening portion 120, and the flow velocity is reduced. Therefore, the speed of the air discharged toward the rear of the vehicle is reduced, so that the pressure drop near the rear door can be suppressed, and the air resistance can be reduced.

Fig. 2 is a view showing a state in which the under cover structure 100 in fig. 1 is viewed from below. As shown in fig. 2, the opening portion 120 may be formed long in the vehicle width direction. Therefore, the air passing under the engine 104 (see fig. 1) can be more efficiently discharged outside the vehicle. It should be noted that the shape of the opening portion 120 is not limited to this shape, and the same effects as the above effects can be obtained if the opening portion 120 is, for example, a plurality of holes arranged in the vehicle width direction.

As shown in fig. 1, in the present embodiment, the under cover 110 has an inclined portion 112 and a horizontal portion 114. The inclined portion 112 is a surface that extends from the front bumper 108 toward the vehicle rear and gently inclines downward. The horizontal portion 114 is a substantially horizontal surface that is continuous with the rear end 112a of the inclined portion 112 and extends from the rear end of the inclined portion 112 toward the vehicle rear. Note that the inclined portion 112 may be inclined at any angle as long as the inclined portion 112 is inclined downward, and the inclined portion 112 may have a flat surface or a curved surface. In addition, the inclined portion 112 and the horizontal portion 114 are preferably smoothly continuous.

Preferably, the opening 120 is disposed in the horizontal portion 114 of the under cover 110. Therefore, the air discharged from the opening portion 120 can be made to interact with the air having the highest velocity as it flows from the vehicle front side below the engine 104 (on the vehicle lower surface side) and then passes through the inclined portion 112. Therefore, the speed of the air passing under the engine 104 can be effectively reduced.

In addition, as shown in fig. 1, in the present embodiment, the horizontal portion 114 is configured to include a front-side horizontal region 114a and a rear-side horizontal region 114b that are arranged on the front side and the rear side of the opening portion 120, respectively. The front horizontal region 114a is a region extending substantially horizontally toward the vehicle rear between the rear end 112a of the inclined portion 112 and the opening portion 120, and the rear horizontal region 114b is a region extending substantially horizontally toward the vehicle rear behind the opening portion 120.

Since the rear horizontal region 114b is provided behind the opening portion 120 as in the above configuration, it is possible to rectify the air flow that has become turbulent by the air discharged from the opening portion 120. Therefore, the flow of air in the engine room 100b flowing toward the lower side of the suspension frame 106 can be smoothly guided rearward at the rear end of the under cover 110. Therefore, the air resistance can be prevented from increasing.

Note that, the present embodiment illustrates a configuration in which the opening portion 120 is disposed between the inclined portion 112 and the front region 114a of the horizontal portion 114, but is not limited thereto. For example, the opening portion 120 may be disposed near the rear end 112a of the inclined portion 112, which is a boundary between the inclined portion 112 and the horizontal portion 114, that is, the opening portion 112 may be disposed near the front end of the horizontal portion 114.

Note that if the opening portion 120 is disposed at the inclined portion 112 of the under cover 110, the opening portion 120 will open toward the vehicle front. In this case, air will flow into the engine room 110b from the front of the under cover 110 and be blocked by the suspension frame 106, thus trapping air in the engine room 100b and increasing air resistance. Therefore, the opening 120 is preferably disposed in the horizontal portion 114 of the under cover 110 as described above.

As shown in fig. 1, in the under cover structure 100 of the present embodiment, the under cover 110 has a pipe portion 130, and the pipe portion 130 extends toward the vehicle front from an edge 120a of the horizontal portion 114 on the vehicle rear side of the opening portion 120 and is inclined upward. The upper end 130a of the pipe portion 130 is located above the lower end of the suspension frame 106.

According to the above configuration, the air passing under the engine 104 is guided by the duct portion 130 so as to be discharged to the outside of the vehicle through the opening portion 120. Therefore, the efficiency of air discharge from the opening 120 can be improved, the amount of air introduced into the engine room 100b can be increased, and the amount of air supplied to the radiator 102 can be increased.

Further, since upper end 130a of tube portion 130 is located above the lower end of suspension frame 106, air flowing toward suspension frame 106 can be quickly discharged to the outside of the vehicle. Note that, although the present embodiment illustrates a configuration in which the upper end 130a of the pipe portion 130 is located above the lower end of the suspension frame 106, this is not limitative. For example, even with a structure in which the upper end 130a of the tube portion 130 is located at the same height as the lower end of the suspension frame 106, the same effects as those described above can be obtained.

Fig. 3 is a diagram illustrating the effect of the under cover structure 100 according to the present embodiment. In fig. 3, the horizontal axis represents the amount of air passing through the radiator, and the vertical axis represents the Cd value (air resistance coefficient). In addition, "embodiment" denotes the under cover structure 100 according to the present embodiment, that is, "embodiment" denotes the under cover structure 100 having the opening portion 120 in the under cover 110. In addition, the "comparative example" shows an under cover structure in which no opening portion is provided in the under cover.

As shown in fig. 3, in the case of the comparative example in which the opening portion is not provided in the under cover, the Cd value is high, and the amount of air passing through the radiator is small. In contrast, in the case of the present embodiment, the Cd value is significantly lower, and the amount of air is larger than in the case of the comparative example. From this, it can be understood that, as in the present embodiment, providing the opening portion 120 in the under cover 110 can increase the flow rate of air passing through the engine room 100b, and thus can improve the cooling performance of the radiator 102.

Although preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it should be understood that the present invention is not limited to the above-illustrated embodiments. It will be apparent to those skilled in the art that various modifications and changes can be made within the scope of the present invention as defined in the appended claims, and these should be construed as being included in the technical scope of the present invention.

Industrial applicability

The invention is suitable for the vehicle body under cover structure.

Description of the reference numerals

100 … underbody shield structure; 100a … vehicle; 100b … engine room; 102 … heat sink; 104 … engine; 106 … suspension frame; 108 … front bumper; 108a … front grill; 110 … underbody shield; 112 … an inclined portion; 112a … rear end; 114 … horizontal portion; 114a … front horizontal region; 114b … rear horizontal area; 120 … opening; 120a … edges; 130 … a tube portion; 130a ….

Claims

1. A vehicle body undercover structure that is disposed below an engine/power unit chamber of a vehicle in which a radiator, an engine/power unit, and a suspension frame are disposed in this order from a vehicle front side, comprising:

an under cover that extends rearward of the suspension frame from a lower end of a front bumper of the vehicle and that constitutes a lower surface of the engine/power unit chamber; and

an opening portion formed in the under cover at a position that is located at a vehicle rear side of a center of the engine/power unit and at a vehicle front side of the suspension frame,

the under cover has an inclined portion and a horizontal portion,

the inclined portion extends from the front bumper toward the rear of the vehicle and is inclined downward,

the horizontal portion is continuous with a rear end of the inclined portion, extends from the rear end toward the rear of the vehicle, is substantially horizontal, and

the opening portion is disposed at the horizontal portion,

the horizontal portion includes:

a front side horizontal portion located between a rear end of the inclined portion and the opening portion, and

a rear horizontal portion located behind the opening,

the under cover further has a tube portion that extends and inclines upward from an edge of the horizontal portion on the vehicle rear side of the opening portion toward the vehicle front, and that

The upper end of the tube portion is located above the lower end of the suspension frame or at the same height as the lower end.