Vehicle front structure

Abstract

To provide a vehicle front structure that suppresses noise caused by entry of air into a space between a front tip end part of a duct and a cross member disposed in front of the duct.SOLUTION: A vehicle front structure includes: a cross member 12 extending in a vehicle width direction in a lower part of a vehicle; a heat exchange device 14 disposed at the rear of the cross member 12 in a vehicle longitudinal direction; and a duct 16 disposed between the cross member 12 and the heat exchange device 14 to guide travel wind to the heat exchange device 14. The cross member 12 has, on a vehicle rear side surface, a recessed groove part 22 recessed toward the vehicle front side and extending in the vehicle width direction. A front tip end part 20 of a duct lower 18 forming the bottom surface of the duct 16 is disposed at a position facing the recessed groove part 22.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a vehicle front structure, and particularly to an air guiding structure at the front of a vehicle.

Background Art

[0002] In a vehicle front structure, if there is a gap between a duct for guiding traveling wind to a heat exchange device and its peripheral members, the traveling wind cannot be properly introduced into the heat exchange device. As a result, it becomes difficult to efficiently cool the heat exchange device. In addition, due to the leakage of traveling wind from the gap, the aerodynamic performance and the like deteriorate. Therefore, conventionally, an air guiding structure for suppressing the formation of a gap between a duct and its peripheral members has been proposed.

[0003] Patent Document 1 discloses an air guiding structure for guiding outside air flowing in from a grill provided on a front bumper cover to a heat exchange device. In this air guiding structure, it is said that by providing a closing member for closing the gap between the tip of the air guiding plate and the front bumper cover, the opening of the gap can be suppressed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, the existence of a gap between the duct and its peripheral members can affect the riding comfort of the vehicle occupants in addition to the deterioration of the cooling efficiency and the reduction of the aerodynamic performance of the heat exchange device described above. For example, when the traveling wind flows into the gap, the tip of the duct may vibrate and generate abnormal noise. The generation of this abnormal noise may cause the vehicle occupants to feel uneasy or uncomfortable, thus impairing the comfort of the vehicle. Even if the structure is designed to prevent the formation of a gap, a gap may still occur due to deformation or variations during assembly. Therefore, a structure is required that can suppress the generation of abnormal noise by eliminating the gap and reduce the sound pressure even if a gap is formed.

[0006] Therefore, in this specification, a vehicle front structure is realized that suppresses abnormal noise generated by air entering the gap formed between the front tip portion of the duct and the cross member disposed in front of the duct.

Means for Solving the Problem

[0007] The vehicle front structure disclosed in this specification includes, at the lower part of the vehicle, a cross member extending in the vehicle width direction, a heat exchange device disposed behind the cross member in the vehicle front-rear direction, and a duct disposed between the cross member and the heat exchange device for guiding the traveling wind to the heat exchange device. The cross member has a concave groove portion that is recessed toward the vehicle front side and extends in the vehicle width direction on the vehicle rear side surface, and the front tip portion of the duct lower part that constitutes the bottom surface of the duct is provided at a position facing the concave groove portion.

[0008] The front tip portion of the duct lower part may be located inside the concave groove portion.

[0009] The front tip portion of the duct lower part may be in contact with the cross member inside the concave groove portion.

Advantages of the Invention

[0010] According to the vehicle front structure disclosed in this specification, since the front end portion of the duct louvre is provided at a position facing the concave groove portion, when the running wind flows in, the front end portion moves and contacts the surface in the concave groove portion. That is, the front end portion enters the concave groove portion. As a result, the sealing performance between the duct and the cross member is improved and it is difficult for a gap to occur. Further, even when a gap occurs, since the flow velocity decreases when the running wind bends when flowing into the concave groove portion, the sound pressure of the generated abnormal noise is reduced.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Mode for Carrying Out the Invention

[0012] Hereinafter, the vehicle front structure will be described with reference to the drawings. In each figure, "Fr", "Up", and "Rh" indicate the front, upper, and right side directions of the vehicle, respectively.

[0013] FIG. 1 is a side view schematically showing a conventional vehicle front structure. Further, FIG. 2 is a side view schematically showing a vehicle front structure according to an embodiment. First, with reference to FIG. 1, the conventional vehicle front structure 10 will be described.

[0014] FIG. 1 is a side view showing the inside of the front room of the vehicle. As shown in FIG. 1, the vehicle front structure 10 includes a cross member 12, a heat exchange device 14, and a duct 16. The cross member 12 is, for example, a cylindrical member having a substantially square cross section and extends in the vehicle width direction at the lower part of the vehicle. More specifically, the cross member 12 is a strength member that crosses the lower part of the vehicle and is coupled to side sills (not shown) below both side doors of the vehicle.

[0015] The heat exchange device 14 is a heat exchanger disposed rearward of the cross member 12 in the vehicle front-rear direction. More specifically, the heat exchange device 14 is composed of a radiator for cooling an engine or a motor provided in the front room of the vehicle, a condenser for cooling a refrigerant used in the refrigeration cycle of the air conditioner, and the like.

[0016] The duct 16 is disposed between the cross member 12 and the heat exchange device 14 and guides the running wind to the heat exchange device 14. The duct 16 is connected to the heat exchange device 14 so as to cover a part or all of the outer peripheral portion of the heat exchange device 14 such as a condenser or a radiator. For example, if the heat exchange device 14 is square, the duct 16 has a rectangular frame shape surrounding it.

[0017] As shown in FIG. 1, the bottom surface of the duct 16 is constituted by the duct lower part 18. And the front end part 20 of the duct lower part 18 is provided at a position facing the surface on the vehicle rear side of the cross member 12. Since the front end part 20 is not fixed to the cross member 12, when the running wind passes near the front end part 20, the front end part 20 and the cross member 12 come into contact with and separate from each other. For example, when the inflow speed of the running wind increases and the wind pressure becomes high, the front end part 20 moves so as to be pressed against the cross member 12 side. On the other hand, when the wind pressure is not relatively high, the front end part 20 simply sways, that is, it only vibrates. And this vibration becomes one of the causes of abnormal noise from the front room. In FIG. 1, the flow of the inflowing running wind is illustrated by a two-dot chain line A.

[0018] In FIG. 1, the state where the front end portion of the duct louver 18 contacts the cross member 12 in the vehicle longitudinal direction is shown in faint ink and is designated by reference numeral 20a. As shown by this front end portion 20a, when there is no gap between the duct 16 and the cross member 12 and the front end portion 20a is pressed against the cross member 12 by a strong wind pressure, problems such as generation of abnormal noise are unlikely to occur. However, since the contact between the duct 16 and the cross member 12 is only in one direction in the vehicle longitudinal direction, the sealing property is low, and as described above, vibration is likely to occur at the front end portions 20 and 20a. Further, when there are variations during manufacturing or assembly, it is more likely to be affected as a sealing function. As a result, abnormal noise may occur when the traveling wind flowing through the gap generated by the wind pressure passes through.

[0019] Next, with reference to FIG. 2, the vehicle front structure disclosed in this specification will be described. In FIG. 2, the same members as those in FIG. 1 are denoted by the same reference numerals, and the description will be omitted as appropriate. As shown in FIG. 2, the cross member 12 has a concave groove portion 22 that is recessed toward the vehicle front side and extends in the vehicle width direction on the vehicle rear side surface. Therefore, when the traveling wind A passes near the front end portion 20 of the duct louver 18, a part of the air flows into the concave groove portion 22 of the cross member 12 and bends at that time. Further, as shown by the broken line, when the front end portion 20 enters the concave groove portion 22, the sealing property between the duct 16 and the cross member 12 is improved. The sealing property will be further described below with reference to FIG. B in which a part of the cross member 12 and the duct 16 is surrounded by a two-dot chain line and enlarged.

[0020] In the enlarged view B of FIG. 2, a cross member 12, a duct louver 18, and a front end portion 20 of the duct louver 18 are shown. As described above, since the front end portion 20 is provided at a position facing the concave groove portion 22 of the cross member 12, its position may be pushed forward due to the influence of running wind, wind pressure in the front room, etc. For example, in the enlarged view B, the state where the front end portion 20 has moved forward is shown by thick ink and thin ink portions, and is displayed as a front end portion 20a and a front end portion 20b, respectively. Here, as shown in the enlarged view B, the front end portion 20a is in contact with the vertical surface inside the concave groove portion 22. On the other hand, the front end portion 20b indicating a state of being further pushed forward is in contact with the front-rear surface inside the concave groove portion 22. That is, in the vehicle front structure disclosed in this specification, different from the conventional configuration, the contact between the duct 16 and the cross member 12 is within the concave groove portion 22, and further becomes two directions in the front-rear direction and the vertical direction. Therefore, the sealing performance is improved compared with the conventional configuration. As a result, even when there are variations during manufacturing and assembly, it is less likely to be affected as a sealing function. This suppresses the generation of a gap between the duct 16 and the cross member 12.

[0021] In addition, in the vehicle front structure disclosed in this specification, in addition to enabling a configuration in which there is no gap between the duct 16 and the cross member 12 as described above, it is also possible to cope with the occurrence of an unexpected gap. As described above, by providing the concave groove portion 22 in the cross member 12, when the running wind passes near the front end portion 20, a part of the air flows into the concave groove portion 22, and the air flow bends at that time. That is, since a part of the air flow path is narrowed, the downstream pressure is narrowed and the pressure loss increases. As a result, since the air is difficult to flow and the flow velocity of the running wind decreases, even if a strange noise is generated due to the gap, the sound pressure of the strange noise is reduced.

[0022] Note that the above description is just an example. In the vehicle front structure disclosed in this specification, it is sufficient that the cross member has a concave groove portion and the front tip portion of the duct lower part that constitutes the bottom surface of the duct is provided at a position facing the concave groove portion. Therefore, other configurations may be changed as appropriate.

Explanation of Signs

[0023] 10 Vehicle front structure, 12 Cross member, 14 Heat exchange device, 16 Duct, 18 Duct lower part, 20 Front tip portion of the duct lower part, 22 Concave groove portion.

Claims

【Claim 1】 At the lower part of the vehicle, a cross member extending in the vehicle width direction, In the vehicle longitudinal direction, a heat exchanger disposed rearward of the cross member, A duct disposed between the cross member and the heat exchanger and guiding running air to the heat exchanger, Comprising, The cross member has a concave groove portion that is recessed toward the vehicle front side on the vehicle rear side surface and extends in the vehicle width direction, The front end portion of the duct lower surface constituting the duct lower is provided at a position facing the concave groove portion, A vehicle front structure characterized by this.

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