JP2011037413A - Underfloor air flow controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control an air flow generated under the floor of a vehicle body without using a mechanical mechanism. <P>SOLUTION: An underfloor air flow controller includes an elastic under-panel 21 provided in the lower surface of the front part of the vehicle body 2 and a stopper part 22 for regulating an elastic deformation of the under-panel 21 by a prescribed variation. The under-panel 21 is deformed downward from the lower surface of the vehicle body 2 by travelling wind pressure introduced from a vent hole 13. Thus, the under-panel 21 can be deformed by the force of air without using the mechanical mechanism and the air flow generated under the floor of the vehicle body 2 can be controlled. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an underfloor air flow control device for controlling an air flow generated around a vehicle during traveling, particularly an air flow generated between the under floor of the vehicle and the ground.

  In general, in order to improve the behavior stability of the vehicle, external force obtained by rectifying the air flow during traveling around the vehicle body, for example, air resistance reducing members using drag and lift are attached to various parts of the vehicle body Yes. Examples of conventional air resistance reducing members include a front under spoiler provided at the lower end of a bumper at the front of the vehicle body, a rear under spoiler provided at the rear of the vehicle body, and the like.

  Further, when the vehicle travels at a high speed of 80 km / h or higher, the air resistance generated around the vehicle body has a relatively small frictional resistance, and the pressure drag occupies 90% or more. Therefore, the exterior of the vehicle body is devised to reduce the pressure by the shape of each part and parts. For example, an underfloor airflow control device such as an under panel is provided on the front spoiler or the lower surface of the vehicle body to reduce the gap between the vehicle and the road surface.

  As described above, when the gap between the vehicle and the road surface is reduced, a negative pressure region is generated between the ground surface and the vehicle floor. As a result, the effect of pressing the vehicle against the ground surface can be enhanced by the negative pressure region generated between the ground surface and the vehicle floor, and the behavior stability of the vehicle can be improved.

  In Patent Document 1 and Patent Document 2, there is a technique for controlling the air flowing under the floor portion of the vehicle by moving an under panel provided on the lower surface of the front portion of the vehicle body by a mechanical movable mechanism including a link mechanism and an actuator. It is disclosed.

JP-A-6-255542 Japanese Patent Laid-Open No. Sho 62-251281

  However, in the techniques disclosed in Patent Document 1 and Patent Document 2, a movable mechanism for moving the under panel is provided at the front end lower part of the vehicle body or the front part under the floor of the vehicle body (in the vicinity of the so-called approach angle). As described above, in the prior art, the mechanical structure such as the movable mechanism is located near the lowest ground height, near the ground, and near the front end of the vehicle body. It was easy to interfere with road surfaces such as entrances and exits of nasty slopes and obstacles such as wheel stops. Furthermore, there is a problem that there is a high probability of causing damage or failure of the movable mechanism itself due to external force at the time of interference.

  Also, if the movable mechanism breaks down while traveling, the problem is that if the movable mechanism breaks down with the under panel lowered below the vehicle body, the under panel may be damaged by contact with the road surface, or the vehicle may not be able to travel. There was also.

  An object of the present invention is to consider the above-described problems and to control the air flow generated in the vehicle body without using a mechanical mechanism in order to improve traveling and handling stability at high speeds. It is to provide a flow control device.

  In order to solve the above problems and achieve the object of the present invention, an underfloor air flow control device of the present invention is an underfloor air flow control device provided in a vehicle having a ventilation opening at the front portion of a vehicle body. An under panel disposed on a lower surface of the front portion of the vehicle body and having elasticity that can be deformed downward from the lower surface of the vehicle body by a traveling wind pressure introduced from a ventilation opening, and elastic deformation of the under panel with a predetermined change And a stopper portion that regulates the amount.

  Further, another underfloor airflow control device of the present invention is provided on an underside of a front part of a vehicle body in a vehicle, and has an under panel having elasticity that can be deformed downward from the underside of the vehicle body, and elastic deformation of the under panel And a stopper portion that regulates the amount by a predetermined deformation amount. Furthermore, an airbag that is disposed above the under panel and elastically deforms the under panel by inflating, an air tank that sends air to the airbag, and an operating pressure that controls the air tank according to the speed of the vehicle and sends it to the airbag And a control unit for adjusting.

  According to the underfloor air flow control device of the present invention, the under panel is elastically deformed downward from the lower surface of the vehicle body by the force of air without using a mechanical movable mechanism such as a link mechanism or an actuator that is prone to failure. ing. As a result, it is possible to prevent failure and breakage of the movable mechanism of the under panel due to the impact force generated during traveling, and it is possible to improve the safety of the apparatus. Further, the underfloor air flow control device of the present invention has a very simple structure of the control mechanism of the under panel, so that the weight of the entire device can be reduced and the number of parts can be reduced. There are also advantages.

1 is a side view showing a vehicle provided with an underfloor air flow control device according to a first embodiment of the present invention. It is the perspective view which looked at the vehicle provided with the underfloor airflow control device which concerns on the 1st Example of this invention from the front. It is sectional drawing which shows the principal part of the vehicle provided with the underfloor airflow control apparatus which concerns on the 1st Example of this invention. It is sectional drawing of the principal part of the vehicle in the state which the under panel of the underfloor airflow control apparatus which concerns on the 1st Example of this invention deform | transformed. It is a side view of a vehicle in the state where the under panel of the underfloor airflow control device concerning the 1st example of an embodiment of the present invention changed. It is a front view of a vehicle in the state where the under panel of the underfloor airflow control device concerning the 1st example of an embodiment of the present invention changed. It is a graph which shows the relationship between the deformation | transformation amount of an under panel in the underfloor airflow control apparatus which concerns on the 1st Example of this invention, and the wind speed of the air which passes a ventilation opening. It is a side view which shows the vehicle provided with the underfloor airflow control apparatus which concerns on the 2nd Example of this invention. It is sectional drawing which shows the principal part of the vehicle provided with the underfloor airflow control apparatus which concerns on the 2nd Example of this invention. It is explanatory drawing which shows the principal part of the underfloor airflow control apparatus which concerns on the 2nd Example of this invention. It is a block diagram which shows the circuit structure of the underfloor airflow control apparatus which concerns on the 2nd Example of this invention. It is sectional drawing of the principal part of the vehicle in the state which the airbag of the underfloor airflow control apparatus which concerns on the 2nd Example of this invention inflated. It is a side view of the vehicle in the state where the airbag of the underfloor airflow control device according to the second embodiment of the present invention is inflated. It is a block diagram which shows the deformation | transformation mechanism of the underfloor airflow control apparatus which concerns on the 3rd Example of this invention.

Hereinafter, embodiments of the underfloor air flow control device of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the common member in each figure. The present invention is not limited to the following form.
The description will be given in the following order.
1. First embodiment example 1-1. Configuration example of underfloor air flow control device 1-2. 1. Operation of the underfloor air flow control device Second embodiment example 3. FIG. Third embodiment

<1. First Embodiment>
1-1. Configuration Example of Underfloor Air Flow Control Device First, with reference to FIGS. 1 to 3, a configuration example of an underfloor air flow control device according to a first embodiment of the present invention (hereinafter referred to as “this example”). explain.
FIG. 1 is a side view showing a vehicle equipped with an underfloor airflow control device of this example, and FIG. 2 is a perspective view of the main part of the vehicle as seen from the front. FIG. 3 is a cross-sectional view showing a main part of the vehicle.

  As shown in FIG. 1, an automobile 1 that is a vehicle equipped with an underfloor air flow control device of this example includes a sedan-type vehicle body 2 that forms the entire outer shell, a skeleton of the vehicle body 2, and supports a chassis and the like. Frame 4 and four wheels 4 attached to the front, rear, left and right lower parts of the vehicle body 2.

  The vehicle body 2 includes a pair of left and right doors 6 constituting left and right side surfaces of the front and rear intermediate portion, a pair of left and right front fenders 7, a bonnet 8, and a trunk 9 provided at the rear. The front fender 7 constitutes the front left and right side surfaces of the vehicle body 2 adjacent to the doors 6. A bonnet 8 continues from the upper part of the front fender 7 and constitutes the upper surface of the front part of the vehicle body 2.

  The bonnet 8 is provided so as to be openable and closable, and a mounting space 11 in which various parts are divided and incorporated is formed in the front portion of the vehicle body 2 with the bonnet 8 opened upward. A rear tail gate spoiler 10 which is an air resistance reducing member is attached to the upper portion of the trunk 9.

  As shown in FIG. 2, a front cover 12 having a ventilation hole 13 is attached to the front portion of the vehicle body 2. Further, as shown in FIG. 3, a radiator 14 and an AC capacitor 16 are fixed to the mounting space 11 in a state of being supported by a radiator core support 17 behind the vent hole 13 of the front cover 12. Then, the cooling air is introduced into the radiator 14 and the AC condenser 16 from the air vent 13 of the front cover 12.

  Further, an underfloor air flow control device 20 is provided at the front portion of the vehicle body 2. This underfloor airflow control device includes an under panel 21 having elasticity, a stopper portion 22 that supports the under panel 21 to be deformable on the vehicle body 2 and restricts deformation of the under panel 21, and a traveling wind introduction guide 15. is doing. The stopper portion 22 includes a restriction plate 23 that supports the under panel 21 and a plurality of stopper pieces 24 that restrict deformation of the under panel 21.

  As shown in FIG. 3, the restriction plate 23 is disposed between the under panel 21, the radiator 14, and the AC capacitor 16. The restriction plate 23 is formed in a substantially flat plate shape, and is provided with a plurality of insertion holes 23a. And the control board 23 is arrange | positioned in the front part of the vehicle body 2 in the state supported by the two attachment stays 33 and 33 (refer FIG. 2). As shown in FIG. 3, the under panel 21 is attached to the restriction plate 23 via a fixing screw 31 and a spring 32 so as to be elastically deformable.

  The under panel 21 is formed as a substantially flat member having elasticity, and is disposed on the lower surface of the front portion of the vehicle body 2 in the vicinity of the vent hole 13. The under panel 21 is disposed below the radiator 14 and the AC capacitor 16 that are supported by the restriction plate 23 that constitutes the stopper portion 22 and is mounted on the vehicle body 2. Specifically, one end of the under panel 21 on the front side of the vehicle body 2 is fixed to the front cover 12 together with the restriction plate 23 via a fixing screw 31, and the other end is fixed to the restriction plate 23 via a spring 32. Has been.

  The material of the under panel 21 includes, for example, a thermoplastic resin, but is not limited thereto, and other flat plate materials having various elasticity can be used.

  In addition, the under panel 21 is provided with a plurality of stopper pieces 24 constituting the stopper portion 22. The plurality of stopper pieces 24 protrude from one surface of the under panel 21 toward the mounting space 11 of the vehicle body 2. The stopper piece 24 includes a rod-shaped shaft portion 24a and a substantially circular contact portion 24b provided at the tip of the shaft portion 24a.

  The shaft portions 24 a of the plurality of stopper pieces 24 are inserted through insertion holes 23 a provided in the restriction plate 23 so as to be movable in the vertical direction. Further, the outer diameter of the contact portion 24b is set larger than the diameter of the insertion hole 23a of the restriction plate 23. And the contact part 24b of this some stopper piece 24 contact | abuts the circumference | surroundings of the penetration hole 23a of the control board 23, and the downward deformation | transformation in the under panel 21 is controlled by predetermined amount (refer FIG. 4). .

  In addition, although the contact part 24b is normally formed in a substantially circular shape, this shape is not necessarily limited to a substantially circular shape, For example, you may form in a square or a hexagon. That is, the shape of the contact portion 24b can be variously set as long as it can contact the periphery of the insertion hole 23a of the restriction plate 23 and stop the deformation of the under panel 21.

  The length of the shaft portion 24a in the plurality of stopper pieces 24 is set so that the stopper piece 24 arranged in the vicinity of the radiator 14 and the AC capacitor 16 is the longest, and becomes shorter as the distance from the radiator 14 and the AC capacitor 16 increases. Is set to The shape of the under panel 21 at the time of maximum deformation is determined by the length of the shaft portion 24a of the plurality of stopper pieces 24.

  That is, by adjusting the lengths of the plurality of stopper pieces 24, the shape of the under panel 21 at the time of maximum deformation and the maximum amount of deformation can be arbitrarily set. For example, it is set to the minimum height from the road surface defined by law, the distance between the vehicle body 2 and the road surface, or the like.

  Of the plurality of stopper pieces 24, the upper restricting stopper piece 24 </ b> A disposed below the radiator core support 17 is set to be shorter than the other stopper pieces 24. The upper restricting stopper piece 24A is interposed between the under panel 21 and the radiator core support 17, and restricts the upward movement of the under panel 21.

  A traveling wind introduction guide 15 formed in an arch shape is provided above the under panel 21. The traveling wind introduction guide 15 guides the traveling wind that has passed through the ventilation port 13 to the under panel 21 side. Thereby, the traveling wind from the ventilation opening 13 can be efficiently guided to the under panel 21 by the traveling wind introduction guide 15.

1-2. Operation of the underfloor airflow controller
Next, the operation of the underfloor airflow control device of this example will be described with reference to FIGS.
FIG. 4 is a cross-sectional view of the main part of the vehicle showing a state where the under panel is deformed. FIG. 5 is a side view of the vehicle showing a state where the under panel is deformed, and FIG. 6 is a front view of the vehicle showing a state where the under panel is deformed.

  As shown in FIG. 4, when the automobile 1 travels at a high speed of, for example, 80 km / h or more, air flows from the air vent 13 of the front cover 12 toward the radiator 14 and the AC condenser 16. The air also flows into the traveling wind introduction guide 15 that guides the traveling wind to the under panel 21 from the vent hole 13. Therefore, the under panel 21 is pushed below the vehicle body 2 by the pressure of the traveling wind introduced from the ventilation port 13. As a result, the stopper piece 44 is lowered downward along the insertion hole 43a of the restricting plate 43, and the under panel 21 is elastically deformed in a substantially arc shape toward the lower side of the vehicle body 2 against the elastic force.

  Thus, in this example, without using a mechanical mechanism, the under panel 21 is deformed by the air passing through the air vent 13 generated when the automobile 1 travels, that is, the traveling wind of the automobile 1. As a result, an underfloor air flow control device 20 is provided that has a very simple configuration that does not use a mechanical movable mechanism such as a link mechanism or an actuator, and therefore is less likely to fail or break due to an impact force caused by uneven steps on the road surface. Is possible. As a result, it is possible to increase the safety of the apparatus and reduce the number of parts of movable mechanisms such as actuators and gears.

  Further, as shown in FIG. 5, the under panel 21 is elastically deformed toward the lower side of the vehicle body 2, thereby narrowing the gap between the under panel 21 and the road surface. And a negative pressure generate | occur | produces between the under panel 21 and a road surface, and the force by which the under panel 21 is pulled to the road surface side acts. Therefore, a force that is pushed down by the pressure from the traveling wind introduced from the air vent 13 from the inside and a force that is pulled toward the road surface by the negative pressure with the road surface act on the under panel 21. Thereby, the under panel 21 can be deformed very easily.

  Further, when the speed of the automobile 1 is increased and the under panel 21 is deformed downward of the vehicle body 2, the contact portion 24b of the stopper piece 24 contacts the periphery of the insertion hole 23a of the restriction plate 23 (see FIG. 4). Thereby, the downward deformation in the under panel 21 can be restricted by a predetermined deformation amount. Furthermore, the shape of the under panel 21 at this time can be set by the lengths of the shaft portions 24 a of the plurality of stopper pieces 24.

  As shown in FIGS. 5 and 6, the under panel 21 is deformed toward the lower side of the vehicle body 2, whereby the flow velocity of the air flowing between the under panel 21 and the road surface increases. According to Bernoulli's theorem, when the flow velocity increases, the pressure under the floor of the vehicle body 2 and the road surface decreases. As a result, a negative pressure region is obtained between the road surface and the under floor of the vehicle body 2, the effect of pressing the vehicle 1 against the road surface is enhanced, and the behavioral stability of the vehicle 1 can be enhanced.

  Further, when the speed of the automobile 1 is slowed down, the pressure from the traveling wind introduced from the ventilation port 13 decreases, and the force pushing the under panel 21 by the traveling wind decreases. Then, the under panel 21 is deformed toward the upper side of the vehicle body 2 by the elastic force of the under panel 21 and the elastic force of the spring 32 connecting the under panel 21 and the regulating plate 23, and returns to the initial state shown in FIG. .

  Thus, the under panel 21 can return to the initial state by its own elastic force. As a result, the problem that the under panel 21 always protrudes below the vehicle body 2 when the movable mechanism fails as in the conventional mechanical device is solved.

Next, with reference to FIG. 7 and Table 1, the relationship between the speed of the automobile 1 and the amount of deformation of the under panel 21 will be described.
FIG. 7 is a graph showing the relationship between the deformation amount of the under panel and the wind speed passing through the ventilation opening. Table 1 also shows that the speed of the vehicle 1 (km / h), the wind speed of air passing through the ventilation port 13 (m / s), the dynamic pressure acting on the under panel 21 (kgf / m ³ ), and the under panel 21 It is a table | surface which shows deformation amount (mm).

  As shown in Table 1, it can be seen that when the speed of the automobile 1 is increased, the wind speed passing through the ventilation port 13 is also increased. Further, as the wind speed increases, the dynamic pressure acting on the under panel 21 also increases substantially proportionally. As the dynamic pressure acting on the under panel 21 increases in proportion to the wind speed, the amount of deformation of the under panel 21 also increases substantially in proportion to the wind speed. That is, since the under panel 21 changes in proportion to the speed of the automobile 1, the distance between the under panel 21 and the road surface can be changed with a very simple configuration.

  Furthermore, it can be seen that when the speed of the automobile 1 exceeds 100 km / h, the deformation amount of the under panel 21 stops at about 70 mm. This is because the deformation of the under panel 21 is restricted by the stopper portion 22 when the deformation amount of the under panel 21 reaches about 70 mm. Therefore, even if the speed of the automobile 1 exceeds 100 km / h, the under panel 21 is not deformed by about 70 mm or more. Thereby, it can prevent that the under panel 21 deform | transforms larger than the space | interval of the vehicle body 2 and a road surface, and the under panel 21 and a road surface contact.

  In addition, the wind speed which passes the ventilation port 13, the dynamic pressure which acts on the under panel 21, and the deformation amount of the under panel 21 are the position and opening area of the ventilation port 13, and the internal space S behind the ventilation port 13 (refer FIG. 4). It changes variously according to the magnitude | size of this and the elastic modulus of the under panel 21.

  In addition, according to the underfloor airflow control device 20 of the present example, the vehicle 1 having the air vent 13 at the front portion of the vehicle body 2 can be provided regardless of the appearance design of the vehicle body 2.

<2. Second Embodiment>
Next, a configuration example of the underfloor air flow control device according to the second embodiment of the present invention will be described with reference to FIGS.
FIG. 8 is a side view showing a vehicle equipped with an underfloor airflow control device according to a second embodiment, and FIG. 9 is a cross-sectional view showing the main part of the vehicle. FIG. 10 is a schematic diagram showing the main part of the underfloor air flow control mechanism according to the second embodiment, and FIG. 11 is a block diagram showing the circuit configuration of the underfloor air flow control mechanism according to the second embodiment. FIG.

  The difference between the underfloor air flow control device 40 according to the second embodiment and the underfloor air flow control device 20 according to the first embodiment is a deformation mechanism for deforming the under panel. Here, parts that are common to the underfloor airflow control device 20 are assigned the same reference numerals, and redundant descriptions are omitted.

  As shown in FIG. 8, the underfloor air flow control device 40 according to the second embodiment is similar to the underfloor air flow control device 20 according to the first embodiment. It is arranged on the lower surface of the part. As shown in FIG. 9, the underfloor air flow control device 40 includes an under panel 21, a stopper portion 42 that restricts elastic deformation of the under panel by a predetermined deformation amount, and a deformation mechanism 46 that deforms the under panel 21 (FIG. 10). Reference).

  In the second embodiment, the under panel 21 has one end on the front side of the vehicle body 2 fixed to the front cover 12 via a fixing screw 31 and the other end not shown on the floor plate 18 of the vehicle body 2. It is fixed via a spring.

  The stopper portion 42 includes a restriction plate 43 that is fixed to the floor plate 18 of the vehicle body 2 and a plurality of stopper pieces 44 that protrude from the under panel 21 toward the mounting space 11 of the vehicle body 2. The plurality of stopper pieces 44 are disposed on the front side and the rear side of the under panel 21 so as to sandwich an airbag 47 of a deformation mechanism 46 described later.

  As shown in FIG. 10A, the deformation mechanism 46 includes an airbag 47 that deforms the under panel 21, an air tank 48, a compressor 51, a control unit 52, a control solenoid valve 53, a tank pressure sensor 54, and two And a line pressure sensor 56.

  On one surface of the airbag 47, a presser plate 49 that restricts the direction in which the airbag 47 inflates is attached. The airbag 47 is connected to an air tank 48 that supplies air to the airbag 47 via two pipes 58. The two pipes 58 are respectively provided with line pressure sensors 56 for detecting the pressure of the air in the airbag 47. A control solenoid valve 53 is provided at one end of the two pipes 58 on the air tank 48 side.

  By opening and closing the control solenoid valve 53, air can be sent from the air tank 48 to the air bag 47, or air accumulated in the air bag 47 can be removed. The air tank 48 is provided with a tank pressure sensor 54 that detects the pressure in the air tank 48. Further, the air tank 48 is connected to a compressor 51 that sends compressed air to the air tank 48 via a pipe 59.

  As shown in FIG. 11, the control unit 52 is connected to two line pressure sensors 56, a tank pressure sensor 54, a compressor 51, and a control solenoid valve 53. The control unit 52 receives the pressure information of the airbag 47 from the two line pressure sensors 56 and the pressure information of the air tank 48 from the tank pressure sensor 54. The control unit 52 is electrically connected to the vehicle ECU 61. Then, the speed signal of the automobile 1 detected by the vehicle speed sensor 62 connected to the vehicle ECU 61 is input to the control unit 52.

  As described above, the control unit 52 outputs a control signal to the compressor 51 and the control solenoid valve 53 based on the speed signal of the automobile 1 and the pressure information of the airbag 47 and the air tank 48. The compressor 51 performs opening / closing control of the control solenoid valve 53 based on a control signal from the control unit 52 and supplies compressed air to the air tank 48. That is, the amount of air supplied to the airbag 47 is adjusted by opening / closing control of the control solenoid valve 53.

  Returning to FIG. 9 again, the airbag 47 is arranged above the under panel 21 with the presser plate 49 in contact with the regulating plate 43 side. That is, the airbag 47 is interposed between the regulation plate 43 and the under panel 21. Further, the air tank 48 is disposed at the front portion of the vehicle body 2. The location where the air tank 48 is disposed is not limited to the front portion of the vehicle body 2 and may be disposed in the trunk 9 or the mounting space 11 (see FIG. 2) of the vehicle body 2.

  Other configurations are the same as those of the underfloor airflow control device 20 according to the first embodiment described above, and thus the description thereof is omitted. Also with the underfloor air flow control device 40 having such a configuration, the same operation and effect as the underfloor air flow control device 20 according to the first embodiment described above can be obtained.

  The underfloor airflow control device 40 according to the second embodiment can be mounted on the automobile 1 that does not have the vent hole 13 in the front portion of the vehicle body 2.

Next, the operation of the underfloor air flow control device 40 according to the second embodiment will be described with reference to FIGS. 10B, 12, and 13.
10B is a schematic diagram of a deformation mechanism showing a state where the airbag 47 is inflated, FIG. 12 is a cross-sectional view showing a main part of the automobile 1 in a state where the airbag 47 is inflated, and FIG. It is a side view of the automobile 1 in the state.

  First, the control unit 52 configuring the deformation mechanism 46 acquires the speed signal of the automobile 1 from the vehicle ECU 61 and the pressure information of the airbag 47 and the air tank 48 from the tank pressure sensor 54 and the line pressure sensor 56. Next, the control unit 52 calculates the working air pressure supplied to the airbag 47 from the acquired speed signal and pressure information. The control unit 52 controls the control solenoid valve 53 and the compressor 51 in accordance with the calculated working air pressure. Air is supplied to the airbag 47 from the control solenoid valve 53 and the compressor 51, and an operating pressure is generated in the airbag 47. Thereby, as shown to FIG. 10B, the airbag 47 expand | swells.

  Here, as shown in FIG. 12, the airbag 47 is interposed between the regulation plate 43 and the under panel 21. Furthermore, a presser plate 49 that restricts the direction in which the airbag 47 inflates is provided on the side of the regulation plate 43 in the airbag 47. Therefore, the airbag 47 is inflated toward the under panel 21 side. As a result, when pressed downward by the airbag 47, the under panel 21 is elastically deformed in a substantially arc shape toward the lower side of the vehicle body 2 against its elastic force. As a result, as shown in FIG. 13, the under panel 21 is deformed toward the lower side of the vehicle body 2, whereby a negative pressure region is obtained between the road surface and the floor under the vehicle 1.

  In addition, when the speed of the automobile 1 becomes slow, the control unit 52 opens the control solenoid valve 53 to reduce the air pressure of the airbag 47. Then, the air pressure of the airbag 47 becomes smaller than the elastic force of the under panel 21, and the air accumulated in the airbag 47 is pushed out by the under panel 21 and is deflated. As a result, the under panel 21 is deformed toward the upper side of the vehicle body 2 so as to return to the initial state shown in FIG.

  In this example, the example in which the deformation amount of the under panel 21 is estimated by the air pressure of the airbag 47 and the elastic coefficient of the under panel 21 and the working air pressure supplied to the airbag 47 is adjusted has been described. It is not limited. For example, a position sensor may be provided in the shaft portion 44 a of the stopper piece 44 and the insertion hole 43 a of the restriction plate 43, and the deformation amount of the under panel 21 may be estimated from the movement amount of the shaft portion 44 a of the stopper piece 44. Thereby, the air quantity supplied to the airbag 47 and / or the air pressure of the airbag 47 can also be adjusted.

<3. Third Embodiment>
Next, an underfloor air flow control device according to a third embodiment of the present invention will be described with reference to FIG.
FIG. 14 is a block diagram showing a deformation mechanism of the underfloor airflow control device according to the third embodiment.

  The difference between the underfloor air flow control device 70 according to the third embodiment and the underfloor air flow control device 40 according to the second embodiment is the configuration of the deformation mechanism. Therefore, here, the deformation mechanism will be described. In addition, since structures other than the deformation | transformation mechanism of the underfloor airflow control apparatus 70 are the same as the underfloor airflow control apparatus 40 concerning 2nd Embodiment, the overlapping description is abbreviate | omitted.

  As shown in FIG. 14, the deformation mechanism 76 of the underfloor airflow control device 70 according to the third embodiment includes an air tank 78, an airbag 77, a compressor 81, and a solenoid valve 83. . The air tank 78 and the solenoid valve 83 are connected by a pipe 88. Further, a pressure reducing valve 91 and a relief valve 92 are provided between the air tank 78 and the solenoid valve 83. Pressure sensors 93 and 93 are connected to the pressure reducing valve 91 and the relief valve 92, respectively.

  The decompression valve 91 is a valve that decompresses air passing from the air tank 78 side, which is the primary side, to the air bag 77, which is the secondary side, by changing the opening of the valve body. Is to do.

  In addition, the relief valve 92 has a function of automatically opening the valve when a predetermined pressure (set pressure) is reached and releasing the fluid, and closing the valve when the pressure drops. Therefore, when a pressure higher than a predetermined value is applied by the relief valve 92, the pressure can be reduced, and the airbag 77 can be prevented from rupturing or the solenoid valve 83 can be broken. Further, the relief valve 92 and the pressure sensor 93 control the speed of the working air pressure when the air bag 77 is depressurized. As a result, when the speed of the vehicle becomes slow, the pressure of the airbag 77 can be quickly reduced.

  The solenoid valve 83 and the airbag 77 are connected by two pipes 89 and 89. The two pipes 89 and 89 have two flow rate control valves 94 and 94 that keep the flow rate of air supplied to the airbag 77 constant, and two pressure sensors 86 and 86 that detect the pressure of the airbag 77. Is provided.

  Other configurations are the same as those of the underfloor airflow control device 20 according to the first embodiment described above, and thus the description thereof is omitted. Also with the underfloor air flow control device 70 having such a configuration, the same operations and effects as those of the underfloor air flow control device 20 according to the first embodiment described above can be obtained.

  The present invention is not limited to the embodiment described above and shown in the drawings, and various modifications can be made without departing from the scope of the invention described in the claims. For example, in the underfloor air flow control device 40 according to the second embodiment and the underfloor air flow control device 70 according to the third embodiment, a plurality of airbags and / or air tanks may be provided.

  DESCRIPTION OF SYMBOLS 1 ... Automobile (vehicle), 2 ... Vehicle body, 11 ... Installation space, 12 ... Front cover, 13 ... Ventilation opening, 15 ... Running wind introduction guide, 18 ... Floor board, 20, 50, 70 ... Underfloor airflow control device, 21 ... Under panel, 22 ... Stopper part, 23,43 ... Regulating plate, 24,44 ... Stopper piece, 24A ... Upper restricting stopper piece, 24a ... Shaft part, 24b ... Abutting part, 31 ... Fixing screw, 32 ... Spring, 33 ... Mounting stay, 46 ... Deformation mechanism, 47 ... Air bag, 48 ... Air tank, 49 ... Presser plate, 51 ... Compressor, 52 ... Control part, 53 ... Control solenoid valve, 54 ... Tank pressure sensor, 56 ... Line pressure sensor 58, 59 ... piping, 61 ... vehicle ECU, 62 ... vehicle speed sensor, S ... internal space

Claims (6)

An underfloor airflow control device provided in a vehicle having a ventilation opening at a front portion of a vehicle body,
An under panel having elasticity that is disposed on a lower surface of a front portion of the vehicle body and is deformable downward from a lower surface of the vehicle body by a traveling wind pressure introduced from the ventilation port;
A stopper for restricting elastic deformation of the under panel with a predetermined amount of change;
An underfloor air flow control device comprising: The underfloor air flow control device according to claim 1, wherein the traveling wind pressure acting on the under panel changes according to a speed of the vehicle. The underfloor air flow control device according to claim 1, wherein the ventilation port also serves as a cooling air introduction port for a cooling device mounted on the vehicle. An under panel disposed on a front lower surface of a vehicle body in a vehicle and having elasticity that is deformable downward from the lower surface of the vehicle body;
A stopper portion that regulates elastic deformation of the under panel by a predetermined deformation amount;
An airbag disposed above the under panel and elastically deforming the under panel by inflating; and
An air tank for sending air to the airbag;
A control unit for controlling the air tank according to the speed of the vehicle and adjusting an air operating pressure to be sent to the airbag;
An underfloor air flow control device comprising: The stopper part is
A plurality of stopper pieces projecting upward from the under panel;
The underfloor airflow control device according to any one of claims 1 to 4, further comprising a restriction plate that restricts downward movement of the plurality of stopper pieces. The underfloor air flow control device according to any one of claims 1 to 5, wherein the under panel is made of a thermoplastic resin.

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