JPH0976948A - Engine undercover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the air introducing performance of an air introducing type engine under cover and the hot air discharging performance of an engine room. SOLUTION: In an air introducing type engine under cover 2 to direct and introduce lower air to a floor tunnel, a twisted-down fin 3 is mounted to the side edge of the engine under cover 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine undercover having a function of introducing air under the engine undercover into a floor tunnel.

[0002]

2. Description of the Related Art Conventionally, there is an air introduction type engine undercover 01 as shown in FIG. In this conventional technique, hot air 0c from the engine room is distributed to the left and right of the front part of the floor tunnel 02 and discharged, thereby preventing mixing with the cool air guided to the underfloor air introduction duct 03. As a result, air having a lower temperature can be supplied to the floor tunnel 02, so that the ambient temperature of the fuel tank 04 installed downstream thereof can be lowered. as a result,
The temperature of the fuel in the fuel tank 03 is lowered, and the generation of gasoline vapor can be reduced. In the drawing, 05 is a center member, 06 is an exhaust pipe, 07 is a suspension member, and 0 is a suspension member.
8 is a floor tunnel air duct, 09 is a catalyzer,
Reference numeral 010 is a heat shield plate, and 011 is a muffler. Further, 0a is cooling air, and 0b is exhaust pipe hot air flow. Incidentally, FIG. 7 shows a cross section taken along lines SB-SB, SC-SC, and SD-SD in FIG.

[0003]

However, in the above-described conventional air-introduction type engine undercover 01, since the air introduction to the floor tunnel 08 depends on the uneven flow performance of the underfloor air introduction duct 03, Tunnel 0
There is a limit to the flow rate of cooler air that can be introduced into the fuel cell No. 8, and the limit is to obtain the effect of lowering the lower surface temperature of the fuel tank 04 by about 3 ° C. In order to prevent the generation of gasoline vapor, it is necessary to further reduce the ambient temperature on the lower surface of the fuel tank 04.

The present invention has been made by paying attention to such a conventional problem, and solves the above problem by improving the air introduction performance of the air introduction type engine undercover, and further, the hot air in the engine room The purpose is to improve the discharge performance.

[0005]

In order to achieve the above-mentioned object, in an engine undercover having an introduction means for introducing air under the front engine undercover toward a floor tunnel, a side end of the engine undercover is provided. I attached a twisted fin to.

[0006]

When air flows under the engine under-cover having the air introduction means, a blade tip vortex is generated due to the pressure difference between the upper and lower sides of the twist fin, and at this time, a cold and fast flow is generated at the end of the twist fin. By hitting, the wingtip vortex becomes stronger.

Since the lower surface of the twisted fin has a high flow velocity, the pressure is low, and the upper surface has a high pressure, so that the pressure difference accelerates the discharge of hot air in the engine room.

[0008] Further, the vortex at the tip of the blade generated by the twist-down fin produces a blow-up induced wind and a blow-down induced wind. Then, the blow-up guide wind can promote the deflection of the flow introduced by the introduction means, while the blow-down guide wind can deflect the hot air from the engine room toward the ground (downward).

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing an embodiment of the present invention. In addition,
This embodiment is applied to a vehicle having the same structure as the conventional art. First, the structure will be described. A conventional twisting fin 3 as shown in the figure is attached to an underfloor air introduction duct 1. The fin 3 is located at a position satisfying the following three conditions, that is, the side end of the air-introducing undercover 2 and the upstream of the underfloor air-introducing duct 1, and the twist-down fin 3 The side edge of the floor is in a position where a sufficiently fast flow under the floor hits it.

FIG. 2 shows the mounting position of the engine undercover 1 with the twist-down fins 3, which is installed on one side of the center member 4 as shown. In the figure, 5 is a suspension member, and 6 is an exhaust pipe.

FIG. 3 shows a three-sided view of the engine undercover 1 with the twist-down fins 3, which is shown in FIG.
Is a plan view, (b) is a front view, and (c) is a side view.

Next, the operation will be described.

As shown in FIG. 4, the cold air A passing under the air introduction type under cover 2 is deflected by the underfloor air introduction duct 1 and guided to the floor tunnel. Further, a blade tip vortex B is generated at the rear end of the fin 3 due to the pressure difference between the upper and lower sides of the twisted fin 3 (see FIG. 5, which is the S5-S5 cross section of FIG. 4). At this time, since the side ends of the fins 3 are twisted down, the following actions occur.

Since the rear end of the side end of the twisted fin 3 is thrust into the fast flow under the floor, a cold fast flow hits the side end, so that the blade tip vortex B is strengthened.

Since the lower surface of the twisted fin 3 has a high flow velocity, the pressure is low (L), and the upper surface thereof has a high pressure (H), so that the pressure difference accelerates the discharge of the hot air C in the engine room, and further, the discharge. The hot air C in the engine room is easily discharged due to the widened outlet and low ventilation resistance.

The blow-up induced wind D induced by the blade tip vortex B generated by the twisted fins 3 promotes the deflection of the flow by the underfloor air introduction duct 1 and introduces more underfloor cold flow into the floor tunnel. Therefore, the amount of cold air introduced into the underfloor air introduction duct 1 increases.

The downwind induction wind E induced by the wing tip vortex B generated by the twisting fins 3 deflects the hot air C from the engine room toward the ground (downward), so that the hot air C discharged from the engine room is generated. Biased under the floor.

As described above, in this embodiment, the temperature difference in the engine room is lowered because the discharge of the hot air C in the engine room is promoted by the pressure difference between the upper and lower sides of the twisting fin 3 (see above). The effect that can be obtained is obtained.

Further, since the amount of cold air introduced into the underfloor air introduction duct 1 is increased by the blow-up induced wind D induced by the blade tip vortex B (see above), the cold air that has entered the floor tunnel is rearward of the floor. Thus, the effect of hitting the front portion of the fuel tank and reducing the heating of the fuel tank by the underfloor flow and cooling the fuel tank depending on the temperature, resulting in a decrease in the fuel temperature and a reduction in the generation of gasoline vapor can be obtained.

Further, since the downwinding induction wind E induced by the blade tip vortex B deflects the hot air C from the engine room to the underfloor (see above), the hot air C in the engine room is deflected downward to cool the underfloor. The rapid flow and hot air can be mixed, and as a result, the effect of lowering the ambient temperature of the lower surface of the tank and reducing the generation of gasoline vapor can be obtained. By the way, when the hot air C flows toward the rear of the floor while licking the floor without deflecting it under the floor, hot air hits the tank and heats the fuel tank.

Further, since the blade fin vortex B is strengthened by providing the twisting fin 3, the above three effects can be increased (see above).

[0022]

As described above, according to the present invention, since the structure is such that the twist-down fins are attached to the conventional air-introduction type engine undercover, the ambient temperature of the fuel tank is lowered, As a result, the effect of lowering the gasoline temperature, the generation of gasoline vapor, and the effect of lowering the temperature in the engine room are obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment.

FIG. 2 is a mounting view of the embodiment.

FIG. 3 is a three-view drawing of an embodiment.

FIG. 4 is an operation diagram of the embodiment.

5 is a sectional view taken along line S5-S5 of FIG.

FIG. 6 is a perspective view of a conventional technique.

7 (b) is an SB-SB sectional view of FIG. 6, (c) is an SC-SC sectional view of FIG. 6, and (d) is an SD-SD sectional view of FIG.

[Explanation of symbols]

 1 Underfloor air introduction duct 2 Air introduction type engine under cover 3 Twisting fin

Claims (1)

[Claims] 1. An engine undercover having an introduction means for introducing air below a front engine undercover into a floor tunnel by directing the twisted fins to a side end of the engine undercover. Undercover.