JPH05301529A - Lower car body structure for automobile - Google Patents

Abstract

PURPOSE:To suppress the occurrence of thermal damage, through which a car room temperature is increased, owing to transfer of hot air in an engine room to a car room, in an automobile wherein a spot below a floor panel forms the engine room. CONSTITUTION:Heat insulating chambers 17a and 17b are formed between a floor panel 3 and an upper partition wall 6 with which an engine room 4 is surrounded. A suction port 16 is formed in the front end parts of the heat insulating chambers 17a and 17b and an exhaust port 18 in the rear end parts thereof. A fan 21 rotated by means of an engine output and sucking external air through the suction port 16 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lower body structure of an automobile in which an engine room is provided below a floor panel.

[0002]

2. Description of the Related Art As a method of mounting an engine on an automobile, for example, Japanese Utility Model Laid-Open No. 3-82679 discloses a technique for accommodating an engine in a space below the floor panel obtained by lifting a floor panel on the front seat side. Has been done. According to this, it is not necessary to mount the engine in the hood at the front of the vehicle like a typical automobile,
To that extent, the degree of freedom in terms of design such as vehicle body design will be expanded.

[0003]

By the way, when the engine is mounted below the floor panel, the hot air in the engine room is transferred to the vehicle interior through the floor panel. The heat damage of rising is inevitable.

Therefore, an object of the present invention is to provide a lower vehicle body structure capable of effectively suppressing the above heat damage in an automobile having an engine room below the floor panel.

[0005]

That is, the invention according to claim 1 of the present invention (hereinafter referred to as the first invention) is a lower body structure of an automobile in which an engine room is provided below a floor panel. There, a heat insulating chamber is formed between the floor panel and a partition wall provided below and covering the upper part of the engine room, and an intake port is provided at a front end portion thereof, and an exhaust port is provided at a rear end portion thereof, It is characterized in that it is provided with an air supply means for flowing the air sucked from the intake port to the exhaust port side through the heat insulating chamber.

The invention according to claim 2 (hereinafter, referred to as the second
(Referred to as an invention), the air supply means is a fan rotated by the output of the engine.

Further, the invention according to claim 3 (hereinafter referred to as the third invention) is characterized in that the air supply means is a fan of a radiator, and the intake port is provided facing the fan.

[0008]

According to the first aspect of the present invention, the heat insulating chamber is formed between the floor panel and the engine room partition wall, and the outside air is positively sent from the intake port to the heat insulating chamber by the air supply means and the exhaust gas is discharged. Since it is discharged from the mouth, the heat insulation chamber is constantly scavenged, and as a result, hot air in the engine room is suppressed from reaching the vehicle interior through the floor panel.

Further, according to the second aspect of the invention, since the fan as the air supply means is driven by the engine output, it is not necessary to provide a drive motor exclusively for the air supply means.

Further, according to the third aspect of the invention, since the fan of the radiator is used as the air supply means, a fan dedicated to air supply is not required.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 show an automobile 1 according to a first embodiment, in which a floor panel 3 is lifted upward in a convex shape between the left and right seats 2 and 2 on the front seat side. The lower part of the floor panel including the space formed by 3a into the lower surface of the floor panel to be fitted upward is used as the engine room 4. In that case, the engine room 4 is formed in a substantially hermetically-sealed state in which only the rear part of the engine room is opened by the upper partition wall 6 covering the upper part of the engine 5 and the transmission housed therein and the lower partition wall 7 covering the lower part. The tips of both partition walls 6 and 7 are extended to a position below the front grille 8 and joined vertically.

Further, in the above automobile 1, the hood 9
A cooler condenser 1 in which traveling wind taken in from the front grille 8 is blown into a chamber 10 formed inside
1, radiator 12 and radiator fan 13,
Other devices such as a battery (not shown) are housed in the room 10 while being connected to the floor panel 3 described above.
The bottom panel 14 forming the bottom wall of the panel is spaced apart from the upper partition wall 6 so that the panel 1
4 and the upper partition wall 6, an air passage 15 is formed, and the air passage 15 opens below the front grill 8 to serve as an intake port 16.

The upper partition wall 6 has a convex portion 3a at a portion corresponding to the convex portion 3a of the floor panel 3.
A bulging portion 6a that protrudes from below is formed, and the upper portion of the main body of the engine 5 is housed in the bulging portion 6a, so that the engine mounting position is increased and the air between the floor panel 3 and the upper partition wall 6 is increased. A space communicating with the passage 15 is provided, and the space serves as a heat insulating chamber. In that case, in the heat insulating chamber, in the portion of the bulging portion 6a, as shown in FIG. 3, the heat insulating chamber 17a above the bulging portion 6a and the bulging portion 6a are provided.
It is composed of heat insulating chambers 17b, 17b on both sides of "a", which are connected to the air passage 15 on the front side of the engine room and to the exhaust port 18 on the rear side of the engine room in a state of communicating with each other. .. Therefore, the intake port 16
As shown in FIG. 2, the air flowing in from the air flows into the heat insulating chambers 17a, 17b, 17b from the air passages 15, passes through these heat insulating chambers 17a, 17b, merges at the exhaust port 18, and then flows out. As described above, it flows above the engine room 4.

Therefore, as shown in FIGS. 2 to 4, the floor panel 3, the bottom panel 14 and the upper partition wall 6 are
On both sides of the upper partition wall 6, the above-mentioned air passages 15 or 19 which are connected to each other by substantially U-shaped frames (not limited to this shape) 19 and which continue from the intake port 16 to the exhaust port 18. Heat insulation chambers 17a, 17b, 17b
Is formed into a duct shape. Further, both side portions of the lower partition wall 7 are also joined to the upper partition wall 6 at the portions of the frames 19 and 19 described above. In that case, welding or fasteners 33 such as bolts and nuts are used for the above-mentioned connection and joining.

Further, the shape of the air passage 15 is such that the air flowing in from the intake port 16 is smoothly insulated.
7b, 17b and is shaped by the upper partition wall 6 so as to be discharged from the exhaust port 18, and a fan 21 is provided in the middle of the air passage 15 by a bracket 20.
Is installed, and the fan 21 keeps the inflow air 17
It is driven by the output of the engine 5 so as to be sent to a, 17b, 17b. That is, in the engine room 4, there is provided a pulley 22 which is rotated by the engine output taken out from the crankshaft or the like, the rotational force of which is transmitted to the first transmission pulley 23 (see FIG. 1) by the belt 24, and the shaft is further rotated. It is transmitted to the second transmission pulley 26 via 25. On the other hand, a pulley 28 is attached to the fan shaft 27 (see FIG. 4) of the fan 21 described above, and a belt 30 spanned between the pulley 28 and the second transmission pulley 26 through an opening 29 provided in the upper partition wall 6. The above rotational force is applied to the fan 21 by. Therefore, while the engine 4 is being driven, the fan 21 rotates, and the outside air is sucked in through the intake port 16 so that the above-described heat insulating chambers 17a, 17b, 17b are obtained.
Will be forcibly supplied to.

As described above, since the air passage 15 is equipped with the fan 21 as an air supply means, outside air is positively discharged from the intake port 16 not only while the vehicle 1 is running but also when the vehicle is idling. It is taken in, flows from the air passage 15 through the heat insulating chambers 17a, 17b, 17b to the exhaust port 18, and is discharged to the outside. Therefore, even if the hot air in the engine room 4 warms the air in the heat insulating chambers 17a, 17b, 17b on the upper partition wall 6, the air in the heat insulating chambers 17a, 17b, 17b flows and is constantly scavenged, and the hot air becomes hot. Since it is carried to the outside, the heating of the floor panel 3 is suppressed, and the rise of the passenger compartment temperature is suppressed.

Further, the air discharged from the exhaust port 18 allows the opening 31 at the rear of the engine room (see FIG. 1).
A negative pressure state is generated in the vicinity of, and the air in the engine room 4 is sucked and discharged to the outside through the opening 31 by the negative pressure, so that the air in the engine room 4 is always replaced, and the engine is It is possible to prevent hot air from being accumulated in the room 4. As a result, the effect of hot air on the passenger compartment side can be better avoided.

In addition, since the fan 21 described above is rotated by the engine output, a drive motor dedicated to the fan is not required, and the cost can be reduced accordingly.

Of the partition walls surrounding the engine room 4, the lower partition wall 7 serves to rectify the air flowing under the engine room and protects the engine 5 and others from flying stones.

FIG. 5 shows a second embodiment of the present invention.
The radiator fan 13 is used as an air supply means to the heat insulation chamber. That is, the hood 32 forming the intake port 116 and the air passage 115 is provided so as to surround the radiator 12, and the air that flows in from the front grill 8 and blows against the cooler condenser 11 and the radiator 12 flows into the radiator fan 13. It is configured to be fed into the intake port 116 by a rotational force. In addition, the air passage 115 includes the floor panel 3 and the upper partition 106.
Insulation chambers 117a, 11 formed between the bulging portions 106a of the
7b so that the air is transferred to the heat insulating chamber 117.
After flowing into a and 117b, it flows into the exhaust port 118 and is discharged to the outside.

Further, in the second embodiment, unlike the first embodiment, the upper partition wall 1 constituting the engine room 104 is formed.
06 and the lower partition wall 107 are opened at their tips to serve as the air inlet 34.

In this embodiment, rotation of the radiator fan 13 blows air into the intake port 116,
In addition, since the heat flows from the heat insulating chambers 117a and 117b to the exhaust port 118 and is discharged to the outside, the scavenging inside the heat insulating chambers 117a and 117b is performed, so that the vehicle interior caused by the hot air in the engine room 104, as in the first embodiment. The rise in temperature is suppressed. When the automobile 101 is traveling, traveling wind is taken into the engine room 104 from the air inlet 34 and flows from the opening 131 at the rear part of the engine room to the outside. Is carried out, the engine room 104
The rise in temperature will be suppressed.

In particular, in the second embodiment, since the radiator fan 13 is used as the air supply means, there is no need to equip a fan dedicated to the air supply, and there is an advantage that the cost increase can be prevented accordingly. ..

[0025]

As is apparent from the above description, according to the present invention, the heat insulating chamber is formed between the floor panel and the engine room partition wall, and the outside air is positively supplied from the intake port by the air supply means. Since it is sent to the heat insulation room and discharged from the exhaust port, the heat insulation room is always scavenged and the hot air from the engine room side is carried out, and this hot air reaches the passenger compartment through the floor panel. Is suppressed. For this reason, heat damage such as an increase in the vehicle compartment temperature can be avoided.

Further, by driving the fan as the air supply means with the engine output, it is not necessary to provide a drive motor exclusively for the air supply means, and the cost can be reduced.

Further, by using a radiator fan as the air supply means, a fan dedicated to air supply is unnecessary,
This can also reduce the cost.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an automobile according to a first embodiment of the present invention.

FIG. 2 is a drawing out of a lower body structure portion with a floor panel removed.

FIG. 3 is a sectional view corresponding to line AA in FIG.

FIG. 4 is an enlarged front view of a fan mounting portion.

FIG. 5 is a schematic configuration diagram of an automobile according to a second embodiment.

[Explanation of symbols]

 1 Car 3 Floor panel 4,104 Engine room 5 Engine 6,106 Upper partition wall 13 Radiator fan 16,116 Intake port 17a, 17b Insulation chamber 18,118 Exhaust port 21 Fan 117a, 117b Insulation chamber

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shiro Nakatani No. 3 Shinchi Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Inventor Koichiro Shimada No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd. (72) Inventor Toru Furusawa No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Inventor Katsumi Sakane No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture (72) Inventor Sachiyo Oyama 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Motor Corporation

Claims (3)

[Claims] 1. A lower vehicle body structure for an automobile, wherein an engine room is provided below a floor panel, wherein a heat insulation chamber is provided between the floor panel and a partition wall provided below the floor panel and covering an upper portion of the engine room. Is provided with an intake port at its front end and an exhaust port at its rear end, and an air supply means for flowing the air sucked from the intake port to the exhaust port side through the heat insulation chamber. The lower body structure of an automobile. 2. The lower body structure for an automobile according to claim 1, wherein the air supply means is a fan rotated by the output of the engine. 3. The lower vehicle body structure of the automobile according to claim 1, wherein the air supply means is a radiator fan, and an intake port is provided facing the fan.