JP2001171454A - Cabin internal air pressure relieving method and device, and vehicle with the device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dissolve an eardrum ache by relieving the sudden rise of air pressure in a cabin generated by the expansion of an air bag. SOLUTION: A first opening closing member 3 and a second opening closing member 4 are provided at both ends of a pressure tight hollow body 2, and the interior of the pressure tight hollow body 2 is in a lower pressure state than the atmospheric pressure. When a rupture member 6 is ruptured by a signal from a sensor 5 for detecting the action of the air bag, the first opening closing part 3 is crushed to open this part, and air in the cabin is sucked into the pressure tight hollow body 2 in the pressure reduced state. The second opening closing part 4 is opened in succession by the suction of air into the pressure tight hollow body 2, and pressurized air in the cabin is released to the outside of the cabin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for alleviating air pressure in a vehicle compartment for reducing air pressure in the vehicle interior. More specifically, a method and apparatus for mitigating air pressure in a vehicle cabin that avoids a sudden rise in air pressure in the vehicle cabin caused by the expansion of an air bag that is activated by a collision of a vehicle such as an automobile, and a vehicle equipped with the device About.

[0002]

2. Description of the Related Art Airbags are widely used to ensure the safety of occupants in the interior of an automobile when a collision occurs. At first, airbags were used only in the driver's seat. However, due to the improvement of airbag quality and cost reduction due to the improvement of airbag technology, and the demand for more safety, airbags used in one car The types and number of bags are increasing.

[0003] That is, airbags are installed not only in the driver's seat but also in the passenger seat and also in the rear seat to prevent injuries caused by a steep forward inclination of the occupant's condition that occur when the vehicle collides with a frontal object. It has become so. Further, side airbags and curtain shield airbags have been widely used to prevent occupants from being injured when another vehicle collides with the side surface (see FIG. 2).

[0004]

As is known, an air bag inflates a flexible bag at the time of collision of a vehicle to prevent the occupant's upper body from suddenly hitting an article in the vehicle. On the other hand, the cabin of an automobile is often closed, especially when it is traveling on a highway, with its windows closed. Therefore, if the airbag operates in the vehicle compartment in a sealed state, the air pressure in the passenger compartment will rise sharply.

[0005] Recently, a phenomenon has been heard that the ear hurts when the airbag is activated. That is, there are cases where the eardrum feels painful. Although a medical study on this condition is considered to be unpublished, according to the inventor's findings during swimming in water, 5 m below the water surface, namely 1.
It is said that the eardrum starts to feel pain at 5 atm.

On the other hand, the space in the cabin of an automobile varies greatly depending on the type of vehicle, the number of occupants, the amount of baggage loaded, and the like, but is estimated to be about 500 liters to 1500 liters. If this space, to be precise, the remaining space is compressed by the operation of the airbag, the air pressure in the vehicle naturally rises instantaneously. For example, if the remaining space is compressed to 1 / 1.5, that is, 67%, the air pressure in the remaining space in the vehicle, which was initially 1 atm, becomes 1.5 atm. Conversely, 335 for a car with 500 liters of remaining space
When compressed to liters, that is, when the space for 165 liters is reduced, the pressure becomes 1.5 atm, and in the case of a 1500 liter automobile, when compressed to 1000 liters,
That is, when the space for 500 liters becomes narrow, the pressure becomes 1.5 atm.

Next, the increase in volume due to the expansion of the airbag will be considered. Widely used for the current driver's seat,
Before inflation, the volume of the airbag with a diameter of 70 cm when inflated is
It is estimated to be about 40-50 liters.

Therefore, the occurrence of pain in the eardrum of the occupant, which is not a problem when only one airbag for the driver's seat is used, is more likely to occur as the number of airbags in the automobile increases. That is taken for granted.
In addition, according to the findings regarding the above-mentioned underwater swimming, the airbag is operated in 0.1 second units, while the pressure reaches 1.5 atm, at which pain occurs in the eardrum, and is gradually applied to the human body. It is considered that the occurrence of pain in the eardrum is caused even by a smaller pressure increase.

FIG. 7 is a graph showing the timing of inflation and contraction of various airbags of an automobile. In the example of FIG. 7, the side airbag, the curtain shield airbag, and the driver's seat airbag operate in this order to expand and then contract. The timing differs depending on the vehicle model, but the common thing is that the timing of inflation and deflation differs depending on the type of airbag (the purpose of protection). The rise in indoor air pressure is not a mere addition of the expansion of all airbags used. However, it is understood that it is caused by the integrated result of expansion and contraction.

[0010] As described above, means for preventing occupant injuries that occur at the time of a car collision have been researched and developed to further improve the performance mainly by using an airbag. But,
Generation of eardrum pain caused by inflation of the airbag,
No measures have been taken to prevent occasional tears of the eardrum.

An object of the present invention is to eliminate the pain of the eardrum caused by the rapid rise in the air pressure in the passenger compartment caused by the expansion of the airbag.

[0012]

According to the present invention, there is provided a method of alleviating air pressure in a vehicle compartment, the method comprising the steps of: The increase in the air pressure in the passenger compartment due to the inflation of the airbag is reduced.

According to another aspect of the present invention, there is provided a method for alleviating the air pressure in a passenger compartment, wherein a hollow body communicating between the inside and the outside of the passenger compartment is kept at a pressure lower than atmospheric pressure.
The air in the vehicle compartment is accommodated in the depressurized hollow body by communicating the vehicle interior with the hollow body in accordance with the operation of the two airbag devices, and then the air in the vehicle interior is communicated by communicating the hollow body with the outside of the vehicle interior. Is discharged to the outside of the passenger compartment.

Further, a vehicle interior air pressure relieving device according to the present invention for achieving the above object has, for example, the following configuration. That is, a hollow body, first opening means provided in a part of the hollow body, and opening a part of the hollow body in response to an operation of an airbag provided in a vehicle compartment, A second opening means provided at a position different from the disposition position to open the hollow body to the outside and discharge the air in the vehicle room to the outside through the hollow body, The inside of the hollow body is constantly maintained at an air pressure equal to or lower than the atmospheric pressure, and the first opening means is opened in response to the expansion of at least one airbag activated by an accident during traveling of the vehicle, and the inside of the vehicle interior is opened. The air is sucked into the hollow body, and the second opening means is operated to discharge the pressurized air in the vehicle compartment to the outside.

Further, a vehicle interior air pressure reducing apparatus according to another aspect of the present invention for achieving the above object has, for example, the following configuration. That is, a communication part that communicates between the vehicle interior space and the outside of the vehicle interior, a closing means that closes the communication part, and the closing means that acts on the closing means in response to an inflation operation of the airbag in the vehicle interior to open the communication part. Opening means.

Further, according to the present invention, there is provided a vehicle provided with one or a plurality of the cabin air pressure mitigation devices.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings showing a preferred example of a vehicular cabin air pressure rapid reduction device to which the present invention is applied.

FIG. 1 is a perspective view illustrating the basic structure of a vehicle interior air pressure reducing apparatus according to an embodiment of the present invention. 1 (hereinafter, referred to as an air reduction device) shown in FIG.
Denotes a pressure-resistant hollow body 2, a first opening closing portion 3 provided at an opening of the pressure-resistant hollow body 2 on the vehicle compartment 9 side, and a second opening provided at an opening of the pressure-resistant hollow body 2 on the vehicle exterior 10 side. Includes closure 4. A rupture member 6 is provided in the first opening closing portion 3. The rupturable member 6 senses a sudden increase in air pressure in the passenger compartment 9 with the sensor 5, and transmits the sensor 5 via a conductor 7.
To open a part of the pressure-resistant hollow body 2 (the opening on the passenger compartment side).

The second opening closing portion 4 provided at the opening on the other end side (outside of the passenger compartment 10) of the pressure-resistant hollow body 2 opens the pressure-resistant hollow body 2 outward to operate the pressure-resistant hollow body 2 during operation. The air in the passenger compartment 9 is discharged to the outside 10 through the vehicle. Therefore, the second opening closing portion 4 is provided on the body plate 8 of the automobile.

In the emptying device 1 of this embodiment, the inside of the pressure-resistant hollow body 2 is maintained at a pressure lower than the atmospheric pressure, preferably a vacuum, before being loaded on a vehicle such as an automobile. Thereby, when the air pressure in the vehicle suddenly increases due to the expansion of the air bag activated by an accident during running of the vehicle, first, the first opening closing portion 3 is opened to release the air in the cabin 9 to the pressure-resistant hollow body 2. Then, the second opening closing portion 4 is actuated to discharge the pressurized air in the cabin 9 to the outside 10.

The air-reducing device 1 of this embodiment adopts a configuration in which the pressure-resistant hollow body 2 is maintained at a pressure lower than the atmospheric pressure so that the air having the suddenly increased air pressure in the passenger compartment is sucked into the pressure-resistant hollow body 2 more quickly. Therefore, the sudden increase in the air pressure in the passenger compartment 9 can be reduced more quickly.

The pressure resistance and volume of the pressure-resistant hollow body 2 may be set based on conditions such as the volume inside the vehicle, the number of airbags installed, the degree of vacuum in the pressure-resistant hollow body 2, and the like. In consideration of weight reduction of the automobile, the pressure-resistant hollow body 2 is 1.5
It is preferable to use a material that is as light as possible, with a pressure resistance of about the atmospheric pressure.

In FIG. 1, a rupturable member (eg, explosive) is used.
6, if the first opening closing portion 3 is configured to be destroyed by a sudden increase in the pressure in the passenger compartment 9 as described later, it is not necessary to use the special rupturable member 6 and the sensor 5. Is more preferable.

Alternatively, an airbag sensor for operating the airbag may be used as the sensor 5.

FIG. 2 is a diagram showing an example of an arrangement of the emptying device according to the present embodiment in a passenger car. (A) of FIG.
Shows a plan view of an automobile, and (B) shows a partial sectional view.

In the example shown in FIG. 2A, the driver airbag 18, the passenger airbag 19, and the side airbag 20
A, 20B, and curtain shield airbag 21A,
21B are arranged, and these airbags
A collision with another object is detected by 5A, 15B, 16A, 16B, and a signal processed by a central processing unit (computer) 17 is transmitted and expanded. In the example shown in FIG. 2, as shown in more detail in FIG. 2B, the emptying device 1 is disposed below the rear seat 14, and the second opening closing portion 4 is disposed below the vehicle body. .

The emptying device 1 is arranged such that the first opening closing portion 3 is arranged toward the interior space of the vehicle, and the second opening closing portion 4 can be opened to the outside space as long as the space allows. Position. That is, as shown in FIG. 2, in addition to being placed on the floor of an automobile, it can be placed in a space inside a door, a space on a ceiling, or the like. Alternatively, the first opening closing portion 3 may be disposed in the front space 22 or the back space 23 of the vehicle, and the first opening closing portion 3 may be disposed facing the vehicle interior space. In this case, the air in the passenger compartment is
Alternatively, it flows to the back space 23. Alternatively, the second opening closing portion 4 may be arranged so as to be openable toward the back space 23 after being arranged on the floor as shown in FIG.

In any case, it is necessary to arrange the emptying device 1 of the present embodiment by utilizing the space in the automobile. Therefore, it is necessary to form the pressure-resistant hollow body of the air-reducing device 1 in various shapes according to the space in the automobile and to exhibit an efficient air discharging function. Hereinafter, FIG.
FIG. 6 illustrates various modes of the pressure-resistant hollow body.

FIG. 3 shows an example of a typical pressure-resistant hollow body 31. The pressure-resistant hollow body 31 shown in FIG.
Air flow 3 as shown in (A) and (B)
6 is preferably formed so that its cross-sectional area increases. Further, it is preferable that the upstream plate-like member 32 be configured to be crushable so as to function as the first opening closing portion 3. That is, FIG. 3 (C) (FIG. 3 (B)
3 (D) showing a cross section taken along line CC in FIG. 3 (a view from the direction of arrow A), a notch 37 is formed on a plate member 32 made of, for example, synthetic resin so as to be stiff but easy to crush. Should be provided. In this case, it is preferable to press the plate-shaped member 32 on the end of the pressure-resistant hollow body 31. In addition, 33 is a rupture member for crushing the plate-like member 32.

As shown in FIG. 3 (E), the plate-like member 34 is attached to the pressure-resistant hollow body 31 by using a hinge 35, and the plate-like member 4 is further provided with a spring (not shown). 34 is preferably pressed against the left end of the pressure-resistant hollow body 31.

FIG. 4 shows various modifications of the pressure-resistant hollow body shown in FIG. The cross-sectional shape of the pressure-resistant hollow body 41 in the example shown in FIG. 4A is flat, and such a shape allows the hollow body 41 to be arranged in a space below the sheet or the like. Also, a trumpet-type pressure-resistant hollow body 51 may be used as shown in FIG. Further, as shown in FIG. 4C, a spiral pressure-resistant hollow body 61 may be used.

In the pressure-resistant hollow body 71 shown in FIG. 5, a plurality of partitions 76a to 76e are arranged inside the body. Properly disposing the partition walls in this way is preferable because a rapid change in the flow velocity of air can be prevented. The plate member 72, the plate member 74, and the hinge 75 correspond to the plate member 32, the plate member 34, and the hinge 35 of FIG. 3, respectively.

In the pressure-resistant hollow body 81 shown in FIG. 6, fluid flow adjusting plates 81a, 81b, 81c and 81d are arranged inside the body along the longitudinal axis of the body. If such an adjusting plate is arranged, the body pressure hollow body 8
This is preferable because the air flow in the airbag 1 can be made laminar, and enables smooth outflow of air.

As a material for forming the emptying device of the present embodiment, metal materials such as iron and aluminum, and various synthetic resins can be used. In consideration of reducing the weight of an automobile, it is necessary to use a material as light as the pressure resistance and durability allow, for example, by forming the pressure-resistant hollow body 81 using a flexible material such as a cloth or a film, and A structure in which a frame for preventing compression at the time is arranged inside may be adopted.

As described above, according to the present embodiment, the pressurized air in the cabin is first housed in the depressurized pressure-resistant hollow body, and then operates to be discharged out of the cabin. A quick discharge of the pressurized air can be achieved. For this reason, a sudden rise in air pressure in the vehicle cabin can be quickly eliminated, which helps to prevent the occurrence of pain in the eardrum of the occupant.

Also, a plurality of emptying devices of the present embodiment are provided,
It is preferable to shift the operation timings since the rise in air pressure of the indoor vehicle body can be completely removed. One configuration example for realizing such an operation will be described with reference to FIG.

FIG. 8 shows a plurality of emptying devices 1A, 1B, 1C.
FIG. 3 is a block diagram showing a schematic configuration for driving the.
In this example, the air reduction device corresponding to each airbag is arranged,
The corresponding emptying device operates according to the operation timing of each airbag. That is, the airbag sensor 1
Based on the detection signals from 5A, 15B, 16A and 16B, the central processing unit 17 outputs an airbag operation signal for operating each airbag such as the driver airbag 18, the passenger airbag 19 and the like.

Each of the air bag operation signals is also used as a signal for driving each of the emptying devices 1A, 1B, 1C,..., And the timing adjusters 101A, 101B, 101C are used.
After the timing is optimally adjusted by ..., the emptying device 1
Are output as drive signals for driving A, 1B, 1C,... According to the above configuration, a plurality of emptying devices are
It can be operated at a different timing.

<Other Embodiments> In the above-described embodiment, the first opening closing portion 3 and the second opening closing portion 4, as shown in FIG. The hollow body 2 is hermetically closed, the inside of the pressure-resistant hollow body 2 is kept at or below the atmospheric pressure, and when the airbag is activated, the first opening closing portion 3 is opened so that the air in the passenger compartment is sucked into the pressure-reduced hollow body. ing. However, the decompression speed in the cabin may be somewhat sacrificed, but the following simple configuration may be adopted.

For example, in the configuration of FIG. 1, the inside of the hollow body 2 is not depressurized, only the first opening closing portion 3 is provided, and the other end of the hollow body 2 is always kept open. Then, the first opening closing portion 3 is opened in accordance with the operation of the airbag, and a communication between the vehicle interior and the exterior of the vehicle interior is established, thereby forming an escape route for air and preventing a rise in air pressure in the vehicle interior. In this case, there is no need to maintain the inside of the hollow body under reduced pressure,
The configuration becomes extremely easy. Further, by arranging a plurality of such emptying devices in the vehicle interior, it is possible to cover the slow pressure reduction speed.

Further, in the above-mentioned structure, since the depressurized closed space is not formed, there is no need to intentionally provide the hollow body 2. Therefore, it is also possible to provide a communication hole in a partition separating the vehicle interior and the outside of the vehicle interior, and to close the communication hole with a lid functioning as the first opening closing portion 3. Note that the sensor 5 shown in FIG.
And the pressure-resistant hollow body 2 may be assembled integrally.

[0042]

As described above, according to the present invention,
It is possible to alleviate a sudden increase in the air pressure in the vehicle cabin caused by the expansion of the airbag, and it is possible to eliminate the pain of the eardrum accompanying this.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one configuration example of a vehicle interior air pressure relief device according to an embodiment of the present invention.

FIGS. 2A and 2B are schematic diagrams illustrating an example of an in-vehicle arrangement of a vehicle cabin air pressure mitigation device according to an embodiment, wherein FIG. 2A is a plan view of the vehicle and FIG. It is a partial sectional view.

3A and 3B are views showing an example of a pressure-resistant hollow body according to the embodiment, wherein FIG. 3A is an overview, FIG. 3B is a side sectional view, and FIG.
Is a front view seen from the A direction, (D) is a cross-sectional view taken along line CC of (C), and (E) is a front view seen from the B direction.

4A and 4B are perspective views showing various examples of a pressure-resistant hollow body according to an embodiment, wherein FIG. 4A is a view of a pressure-resistant hollow body having a special cross-sectional shape, and FIG. 4B is a pressure-resistant hollow body having a trumpet-like shape; (C) is a view of a helical pressure-resistant hollow body.

FIG. 5 is a side sectional view showing a pressure-resistant hollow body having a partition therein.

6A and 6B are views showing a pressure-resistant hollow body in which a fluid flow adjusting plate is disposed along a longitudinal axis direction, wherein FIG. 6A is a side sectional view, and FIG. FIG.

FIG. 7 is a diagram showing an example of timings of inflation and contraction of various airbags used in a vehicle.

FIG. 8 is a block diagram illustrating control porosity for operating a plurality of vehicle interior air pressure relief devices at different timings.

[Explanation of symbols]

1 Cabin air pressure mitigation device 2,31,41,51,61,71,81 Pressure-resistant hollow body 3,32,42,52,62,72,82 First opening closing part 4,34,44,54,64, 74, 84 Second opening / closing portion 5, 15A, 15B, 16A, 16B Airbag sensor 6, 33 Rupture member 8 Body plate 9 Vehicle interior 10 Vehicle exterior 11 Passenger car (vehicle) 18 Driver seat airbag 19 Passenger seat air Back 20A, 20B Side airbag 21A, 21B Curtain shield airbag 22 Front space of vehicle 23 Backspace of vehicle 35, 45, 55, 65, 75, 86 Hinge 37 Notch 76a-76e Partition wall 86a-86d Fluid flow control plate

Continued on the front page (72) Inventor Kazuhisa Watanabe 2-12-8 Nishi Mizuhodai, Fujimi-shi, Saitama W-Data Service Co., Ltd. F-term (reference) 3D054 AA02 AA03 AA04 AA16 AA20 EE06 EE19 EE20 EE30 EE34 FF06

Claims (30)

[Claims] A vehicle according to claim 1, wherein a communication portion communicating between the inside and outside of the vehicle compartment is opened in response to the operation of at least one airbag device, so that an increase in air pressure in the vehicle compartment due to inflation of the airbag is reduced. Air pressure relief method. 2. A hollow body communicating between the inside and outside of the vehicle compartment is maintained at a pressure lower than the atmospheric pressure, and air in the vehicle compartment is decompressed by communicating the vehicle room with the hollow body in response to operation of at least one airbag device. A method of alleviating air pressure in a vehicle interior, comprising: receiving the air in the vehicle interior to the outside of the vehicle interior by communicating the hollow body with the outside of the vehicle interior after receiving the air in the hollow interior. 3. The method according to claim 2, wherein a plurality of the hollow bodies are provided, and the timing of communication between each hollow body and the vehicle compartment is shifted. 4. A hollow body, first opening means provided in a part of the hollow body, and opening a part of the hollow body in response to an operation of an airbag provided in a vehicle compartment, the first opening means; A second opening means which is provided at a position different from the arrangement position of the opening means, opens the hollow body to the outside, and discharges the air in the vehicle interior to the outside through the hollow body. The inside of the hollow body is always maintained at an air pressure equal to or lower than the atmospheric pressure, and the first opening means is opened in response to the expansion of at least one airbag activated by an accident during traveling of the vehicle. An air pressure relieving device for a vehicle interior, wherein air in a vehicle interior is sucked into a hollow body, and then the second opening means is operated to discharge pressurized air in the vehicle interior to the outside. 5. The method according to claim 1, wherein the first opening means is a plate-shaped member disposed in a part of the hollow body, and the plate-shaped member is provided with at least one notch-shaped weak portion. The vehicle interior air pressure relieving device according to claim 4. 6. The apparatus according to claim 1, wherein said second opening means is a plate-shaped member which is normally pressed against said hollow body by a pressure difference between the inside of said hollow body and atmospheric pressure. The vehicle interior air pressure relieving device according to claim 4. 7. The airtight hollow body has a cylindrical cross-sectional shape, a first opening means is provided at one end thereof, and a second opening means is provided at the other end thereof. 3. The air pressure relieving device for a vehicle interior according to claim 1. 8. The vehicle interior air pressure mitigation device according to claim 4, wherein a cross-sectional shape of the hollow body is a deformed shape adapted to a shape of a spare space in the vehicle interior. 9. The vehicle interior air pressure mitigation device according to claim 5, wherein a cross-sectional shape of the hollow body changes in a longitudinal direction corresponding to a shape of a spare space in the vehicle interior. 10. The air pressure mitigation device according to claim 4, wherein a sectional area of the second opening means is larger than an area of the first opening means. 11. The apparatus of claim 4, wherein the hollow body has a helical shape. 12. At least one interior of said hollow body
The vehicle compartment air pressure mitigation device according to claim 4, wherein the plurality of partition walls are arranged in a cross-sectional direction, and the partition walls are provided with an opening for air circulation. 13. The air pressure mitigation according to claim 12, wherein two or more partition walls are arranged inside the hollow body, and a cross-sectional area of an air flow opening of the partition wall changes. apparatus. 14. At least one interior of said hollow body
The apparatus according to claim 4, wherein a plurality of fluid flow control plates are disposed along a longitudinal axis of the hollow body. 15. At least a first of said airtight hollow body.
5. The apparatus according to claim 4, wherein the portion excluding the opening means and the second opening means is made of a material selected from a group of metals including iron and aluminum. 16. The air pressure of a vehicle interior according to claim 4, wherein said air-resistant hollow body is made of a material selected from a non-metal group including a synthetic resin and a reinforced synthetic resin. Mitigation device. 17. The method according to claim 4, wherein the hollow body has a shape holding frame inside, and is formed by arranging a flexible material such as a cloth and a film outside the frame. A vehicle interior air pressure relieving device as described in the above. 18. An output of a sensor for activating at least one airbag provided in a vehicle interior for opening a part of the hollow body in response to an operation of an airbag. The vehicle interior air pressure mitigation device according to claim 4, wherein a signal is used in combination. 19. The air pressure of the vehicle compartment, wherein the first opening means is provided independently of a sensor for operating an airbag to open a part of the hollow body in response to the operation of the airbag. The air pressure alleviation device according to claim 4, wherein a signal from a pressure sensor for detecting a rapid increase in the vehicle interior is used. 20. The apparatus according to claim 19, wherein a sensor for detecting a sudden increase in the cabin air pressure and the hollow body are integrally assembled. 21. The apparatus according to claim 4, wherein said second opening means is arranged to directly communicate with the outside of the vehicle.
3. The air pressure relieving device for a vehicle interior according to claim 1. 22. The vehicle interior air pressure relieving device according to claim 4, wherein the second opening means is arranged so as to communicate with a front or rear trunk room of the vehicle. 23. A communication portion that communicates between the vehicle interior space and the outside of the vehicle interior, a closing device that closes the communication portion, and the communication portion that acts on the closing device in response to an inflation operation of an airbag in the vehicle interior. Opening means for opening the vehicle interior air pressure reducing device. 24. The communication part includes a hollow body having a vehicle-side opening and an external-side opening, and the closing means includes a first closing part that closes the vehicle-body-side opening of the hollow body. And a second closing portion for closing the external opening, wherein a closed space is formed in the hollow body by the closing means, and a pressure in the closed space is maintained at an atmospheric pressure or less. An air pressure mitigation device according to claim 23. 25. The cabin according to claim 24, wherein the opening means acts on the closing means so that the second closing part is opened after opening the first closing part. Air pressure relief device. 26. The opening means acts on the first closing portion in response to an inflation operation of an airbag to open a compartment-side opening of the hollow body, and the second closing portion connects the hollow body to the hollow body. 26. The vehicle interior air pressure relieving device according to claim 24, wherein the opening is opened by inflow of air. 27. The air conditioner according to claim 27, wherein the opening means detects air pressure in the vehicle interior and acts on the closing means to open the communication part when the air pressure in the vehicle interior exceeds a predetermined value. Item 24. A vehicle interior air pressure reducing device according to item 23. 28. The opening means detects an air pressure in a vehicle interior, and acts on the closing means to open the communication part when an increasing speed of the air pressure in the vehicle interior exceeds a predetermined value. The vehicle interior air pressure relief device according to claim 23, wherein: 29. The opening means acts on the closing means to open the communication part based on a signal from a sensor for operating at least one airbag in the vehicle interior. 24. The vehicle interior air pressure relieving device according to claim 23. 30. A vehicle provided with one or more of the cabin air pressure mitigation devices according to claim 4.