JPH0747840A - Door structure for automobile - Google Patents

Abstract

PURPOSE:To suppress bending deformation to a small amount in an intermediate part of a beam by inflating boots, provided in the intermediate part of the beam, with gas generated in a gas generator, brought into contact with an inner panel internal surface, when a side impact beam is bent by side collision. CONSTITUTION:Another vehicle collides against a side door 10 in a car body side surface, and when this side collision is detected by a collision sensor 18, an ignition signal is output from a control part, to ignite a gas generating agent in an inflater 12. In this way, a large amount of gas is generated from the gas generating agent, and the generated gas, after the inside of a steel pipe (beam) in a sealed condition is filled with the gas, is jetted from a plurality of through holes 13 formed in intermediate two parts of the beam 11, to instantaneously inflate boots 14 of covering the outside. As a result, in the intermediate point two parts of the beam 11 supporting only both ends by a bracket 15, a new supporting point by the inflated boots 14 is formed, and a span of generating bending deformation is shortened to suppress the bending deformation to a small amount.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a side impact beam provided in a door at the time of a side collision of a vehicle so that a side impact beam is deformed by an external force due to the collision so as to reduce a deformation amount. The present invention relates to an automobile door structure in which the number of supporting points of the impact beam is increased to reduce the deformation amount of the side impact beam.

[0002]

2. Description of the Related Art As a conventional door structure having a side impact beam of an automobile, there is one shown in FIGS. 13 to 15, for example. In this structure, a side impact beam 3 in which brackets 2 are welded to both ends of a straight pipe 1 made of steel pipe is provided in a door between an outer panel 5 and an inner panel 6 of a door 4, and a front and rear body of the door 4 is provided. The brackets 2, 2 are bolted to beam mounting stays (not shown) at both ends in the direction, and are mounted substantially horizontally at a position close to the inner surface of the outer panel 5 (see FIG. 14).

When another vehicle collides with the side door, the side impact beam 3 causes
The collision vehicle is prevented from entering the vehicle interior and the impact is absorbed by the deformation of the side impact beam 3, the bracket 2 and the stay. However, the collision vehicle has an extremely high speed and is input by the collision. When the external force applied is particularly large, this side impact beam 3
The structure is such that the impact is absorbed by bending.

[0004]

However, in the above-mentioned conventional door structure having the side impact beam, since the side impact beam 3 is fixed only at both ends thereof, the central portion of the beam is collided at the time of side collision. However, there was a problem that the bending moment was maximized and the amount of bending deformation was increased.

Therefore, it is conceivable to reinforce the beam central portion where the bending moment of the side impact beam is maximum. Japanese Utility Model Publication No. 62-194117 discloses a side impact beam made of a steel plate having two beads formed in the longitudinal direction. In this side impact beam, a steel pipe having an outer diameter inscribed in the recess is cut into a predetermined size and fitted into the recess of the two beads as a reinforcing material for increasing the bending strength of the central portion. A steel plate is welded to the opening side of the recess to close it. Therefore, by providing the side impact beam made of steel plate in the door, even if the bending moment is concentrated in the central portion of the side impact beam at the time of a side collision of the vehicle, the two steel pipes suppress the bending deformation of the central portion. It is like this.

However, in order to suppress the bending deformation of the middle portion of the side impact beam, a reinforcing steel pipe having a large strength is required, so that the wall thickness of the steel pipe to be used becomes large or the diameter becomes large, and There is a problem that the impact beam becomes large and the weight also increases.

The present invention has been made in view of the above circumstances, and it is possible to suppress the bending deformation amount of the intermediate portion of the side impact beam which is deformed at the time of a side collision, without increasing the beam cross-sectional area and the beam weight. It is an object of the present invention to provide an automobile door structure that can be used.

[0008]

As a means for solving the above problems, the present invention provides a vehicle door structure having a pipe-shaped side impact beam in a door between a door outer panel and a door inner panel. The side impact beam is airtightly closed at both ends thereof and is supported and attached near both ends of the door in the vehicle front-rear direction, and the collision of the side impact beam to the side impact beam attachment position is caused in the hollow beam. A gas generator that ignites and generates a large amount of gas when detected is further provided with a plurality of through holes on the outer peripheral wall of the beam. It expands by the gas ejected from a plurality of through holes and expands between the side impact beam and the door inner panel to produce a side impact. It is characterized in that the boot has a flexible to form a new support points over arm is provided in a deflated state.

Further, in a door structure of an automobile having a pipe-shaped side impact beam in the door between the door outer panel and the door inner panel, both ends of the side impact beam are hermetically closed, and the vehicle body of the door. It is supported and attached near both ends in the front-rear direction,
A through hole is formed in the outer peripheral wall of the beam, and the through hole is sealed with an easily openable closing member, and high-pressure gas is enclosed in the hollow beam while facing the inside of the through hole. When the side impact beam is deformed, a needle-like member that breaks the blocking member and ejects the enclosed gas is provided. Further, the side impact beam is expanded to the outside of the through hole by the gas ejected from the through hole. It is characterized in that the flexible boot that is expanded between the door inner panel and the door inner panel to form a new support point of the side impact beam is provided in a contracted state.

[0010]

When a side collision to the side impact beam mounting position is detected by the collision sensor, an ignition signal is sent directly or indirectly from the collision sensor to the gas generator provided in the hollow portion of the side impact beam. And gas is generated. The generated gas fills the side impact beam whose both ends are closed, and then is ejected from a plurality of through holes to expand the boots that cover the outside of the through holes. Therefore, when the side impact beam is deformed and bent due to the external force due to the side collision, the boot developed between the inner panel and the inner panel is brought into contact with the inner surface of the inner panel at the intermediate portion of the side impact beam whose both ends are supported. As a result, it becomes a new supporting point in the middle portion of the side impact beam and suppresses bending due to external force.

Further, high-pressure gas is enclosed in a hollow side impact beam whose both ends are airtightly closed, and
When the needle-like member formed on the outer peripheral wall of the side impact beam and facing the through hole that is airtightly closed by the closing member breaks through the closing member that closes the through hole as the side impact beam is deformed. High-pressure gas is ejected from this through hole to inflate the boot covering the outside.
Therefore, when the side impact beam is deformed and bent due to the external force due to the side collision, the boot developed between the inner panel and the inner panel is brought into contact with the inner surface of the inner panel at the intermediate portion of the side impact beam whose both ends are supported. As a result, it becomes a new supporting point in the middle portion of the side impact beam and suppresses bending due to external force.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A vehicle door structure of the present invention will be described below with reference to FIGS.

FIGS. 1 to 3 show a first embodiment of the present invention. A side impact beam 11 mounted in a side door 10 of a vehicle has a steel pipe 11a cut into a predetermined size at a substantially central portion thereof. An inflator 12 containing a gas generating agent is arranged. Also, this steel pipe 11a
A plurality of through-holes 1 are provided at intermediate points near both ends of
3 are formed on the same circumference. Further, outside the plurality of through holes 13 formed at two points of these midpoints, a flexible and inflatable boot 14 is provided in a contracted state to surround the outer circumference of both the midpoints of the steel pipe 11a. Each is mounted so as to wrap it airtight. At both ends of the steel pipe 11a, a bracket 15 made of steel is fitted in the mounting holes 15a at both ends of the steel pipe 11a in an airtight manner to hermetically seal and simultaneously firmly weld the side impact beam 11 to each other. It is configured.

The side impact beam 11 constructed as described above is provided with brackets 15 and 15 at both ends thereof in the inner space between the door outer panel 10a and the door inner panel 10b of the side door 10.
Stays 16 attached to both ends of the vehicle body in the front-rear direction,
16 are respectively fastened to the door outer panel 10a by bolts and nuts 17, and are mounted horizontally and parallel to the door outer panel 10a.

Reference numeral 12a in FIG. 1 indicates a steel pipe 1.
A lead wire of the inflator 12 that extends airtight from the inside of the la 1 and a bolt hole 15b for fastening the bracket 15 are shown. Further, in FIG. 2, reference numeral 18 indicates a door outer panel 1
It is a collision sensor attached to the inner surface of 0a. As the collision sensor for detecting the side collision, it is necessary to detect the collision as soon as possible and to inflate the boots 14, 14, and therefore the door outer panel 10 that is first deformed at the time of the side collision.
A strain gauge that is attached to a and detects a collision when it is distorted by a certain amount or more is suitable. Further, since this strain gauge is small, it is also suitable to be installed in a narrow side door 10.

Next, the operation of this embodiment configured as described above will be explained. When another vehicle collides with the side door 10 on the side surface of the vehicle body, this side collision is first caused.
The collision sensor 18 provided on the inner surface of the outer panel 10a of No. 0 detects and transmits a collision detection signal to a control unit (not shown), and an ignition signal (ignition current) from this control unit is transmitted via the lead wire 12a of the inflator 12. The gas generating agent in the inflator 12 is ignited by flowing through a squib (electric detonator) (not shown). The ignited gas generating agent momentarily burns to generate a large amount of gas, and the generated gas fills the steel pipe 11a in a sealed state, and then a plurality of the gas pipes are formed at two intermediate points of the steel pipe 11a. The boots 13 and 13 which are sprayed from the through holes 13 of the above and cover the outside are instantly expanded.

Therefore, the boot 14 is inflated in an extremely short time after the collision sensor 18 detects a side collision,
As a result, new supporting points due to the inflated boot 14 are formed at two intermediate points of the side impact beam 11 whose both ends are supported by the bracket 15, and as a result, the inflating of the boots 14 and 14 is almost the same. At the same time or with a slight delay, when the side impact beam 11 is deformed by an external force due to a collision, the hard and inflated boots 14 and 14 are interposed between the door inner panel 10b and the side impact beam 11, so that bending deformation occurs. The span is shortened, so that the amount of bending deformation is suppressed to a small amount and the amount of displacement toward the passenger compartment is also reduced (see FIG. 3).

In particular, since the inflated boots 14 and 14 come into contact with the inner surface of the door inner panel 10b over a relatively large area, the external force applied to the impact beam 11 is dispersed over a large area, and the door inner panel 10b is exposed. The amount of deformation can also be kept small.

Further, in this embodiment, since the plurality of through holes 13 through which the gas is ejected are formed near both ends of the steel pipe 11a having a relatively small bending moment, the strength of the side impact beam 11 can be reduced. Can be avoided.

4 to 6 show a second embodiment of the present invention. In the first embodiment, an electric sensor and an electric ignition type inflator are used, whereas electricity is used. It employs a method of mechanically ejecting gas without doing so, and will be described below with reference to the drawings.

The side impact beam 21 installed in the side door 20 of the vehicle has a hole 23 for gas injection in the portion facing the door inner panel 20b at the time of installing the door, in the approximate center of the steel pipe 21a cut into a predetermined size. While being formed, this hole 23 is airtightly closed by a thin film 23a so that it can be easily perforated with a needle or the like. Further, in the steel pipe 21a, a needle 23b is provided so as to face the inside of the hole 23 closed by the thin film 23a, and is substantially perpendicular to the axis of the steel pipe 21a on the inner wall surface of the steel pipe 21a on the door outer panel 20a side. Is erected so that Further, a boot 24 having flexibility is airtightly attached to the outer periphery of the steel pipe 21a so as to cover substantially the entire length of the steel pipe 21a except both ends thereof.
Inflatable portions 24a and 24a, which are preliminarily formed to be easily inflated, are provided at two locations corresponding to 3 and 23.

At both ends of the steel pipe 21a, brackets 25 made of steel are hermetically fitted by fitting the ends of the steel pipe 21a into the mounting holes 25a, respectively, and further firmly connected by welding. The side impact beam 21 is configured by filling a non-combustible and harmless high-pressure gas such as nitrogen gas into the hollow portion of the steel pipe 21a from a gas filling valve 29 having a check function attached to one bracket 25. .

The side impact beam 21 constructed as described above is provided between the door outer panel 20a and the door inner panel 20b of the side door 20 with brackets 25, 25 at both ends thereof via stays 26, 26. It is attached to both ends of the side door 20 in the vehicle front-rear direction. In FIG. 4, reference numeral 25a is a bracket 25.
Bolts for fastening the stays to the stay 26, reference numeral 2 in FIG.
1b is a hole formed in the door inner panel 20b so as not to hinder the stroke of the needle 23b.

Next, the operation of this embodiment configured as described above will be explained. When another vehicle collides with the side door 20 on the side surface of the vehicle body, the door outer panel 20a of the side door 20 is first deformed, and then, The side impact beam 21 is pressed by the deformed door outer panel 20a,
It deforms into two folds at the center where the bending moment is maximum. The side impact beam 21 that is deformed into two folds is crushed at its central portion, and the needle 23b erected on the inner wall surface approaches the hole 23, pierces the thin film 23a blocking this hole 23 and breaks it. Then, from the hole 23 to the steel pipe 21
The high-pressure gas filled in a is ejected. Then, the ejected gas is distributed inside the boot 24 toward both ends, and instantly inflates the two inflating portions 24a, 24a at both ends.

Accordingly, new supporting points are formed by the inflated boots 24, 24 at two intermediate points of the side impact beam 21 whose both ends are supported by the bracket 25. As a result, the side impact beam 21 that is in the process of being deformed has the inflated boots 24, 24
Is the door inner panel 20b and side impact beam 2
1, the span causing bending deformation is shortened. Therefore, the amount of bending deformation is suppressed to a small amount, and the amount of displacement toward the passenger compartment is also reduced (see FIG. 6).

In particular, since the inflated boots 24, 24 come into contact with the inner surface of the door inner panel 20b over a relatively large area, the external force applied to the impact beam 21 is dispersed over a wide area, and the door inner panel 20b is exposed. The amount of deformation can also be kept small.

Further, in this embodiment, an electric sensor for detecting a collision is unnecessary, an inflator composed of a gas generating agent and a squib is not necessary, and electric equipments and electric circuits are not used. There is no cause of malfunction due to noise, it has high reliability, and cost can be reduced. Also, stable operation performance can be obtained without disconnection at the time of collision or inoperable state due to damage to the power supply section. Furthermore, even if different doors are hit one after another,
Since the mechanism is independent for each door, the airbag can be activated each time.

FIGS. 7 to 9 show a third embodiment of the present invention. In the second embodiment, one hole for ejecting high pressure gas is formed at the center of the steel pipe. Since it is formed at two locations, the same components as those of the second embodiment are designated by the same reference numerals, detailed description thereof will be omitted, and the following description will be made with reference to the drawings.

The side impact beam 31 installed in the side door 30 of a vehicle has holes 33, 33 for ejecting gas on the side facing the door inner panel 20a near both ends of a steel pipe 31a cut into a predetermined size. While being formed, the holes 33, 33 are airtightly closed by a thin film 33a so that they can be easily perforated with a needle or the like. Further, in the steel pipe 31a, a narrow metal plate is formed to be shorter than the overall length of the steel pipe 31a, needles 33b and 33b are erected at both ends of the same surface, and the surface on which the needle 33b is erected is formed. A pushing bar 32 bent in a V shape at the center so as to be on the inside is attached by welding the central portion to the center of the inner surface of the steel pipe on the door outer panel 20a side. The needles 33b, 33 that are erected on both ends of the
b are arranged close to each other inside the holes 33, 33 formed in the steel pipe 31a.

The holes 3 formed near the both ends of the steel pipe 31a and closed by the thin films 33a, 33a.
Flexible and inflatable boots 34 are independently provided on the outer sides of 3, 33, and each boot 34 is attached so as to wrap the outer circumference of the steel pipe 31a in an airtight manner in a contracted state. . At both ends of the steel pipe 31a, steel brackets 25 are attached to the mounting holes 25a of the respective ends of the steel pipe 31a in an airtight manner to hermetically seal and firmly connect them by welding. A side impact beam 31 is configured by filling a non-combustible and harmless high-pressure gas such as nitrogen gas into the hollow portion of the steel pipe 31a from a gas filling valve 29 having a check function attached to the side impact beam 31.

The side impact beam 31 constructed as described above is provided between the door outer panel 30a and the door inner panel 30b of the side door 30 with brackets 25, 25 at both ends thereof via stays 26, 26. It is attached to both ends of the side door 30 in the vehicle front-rear direction. In FIG. 7, reference numeral 25a is a bracket 25.
It is a bolt hole for fastening.

Next, the operation of this embodiment configured as described above will be explained. When another vehicle collides with the side door 30 on the side surface of the vehicle body, the door outer panel 20a of the side door 30 is first deformed. Then, the side impact beam 21 is pressed by the deforming door outer panel 20a and is deformed into two folds at the center where the bending moment is maximum. When the side impact beam 21 is deformed into two folds, the needles 33b, 33b erected at both ends of the push bar 32 mounted inside the side impact beam 21 approach the holes 33, 33, respectively, and close the hole 33. The thin film 33a is stuck and broken. As a result, the high pressure gas with which the steel pipe 31a is filled is ejected from the hole 33 and flows into the boots 34, 34 to instantly expand.

Therefore, as in the case of the second embodiment, new support points are formed by the inflated boots 34 and 34 at two intermediate points of the side impact beam 31 whose both ends are supported by the bracket 25. As a result, as a result, the side impact beam 3 in the middle of deformation
Since the boots 34, 34 in which 1 is hard and inflated are interposed between the door inner panel 30b and the side impact beam 31, the span between the supporting points is shortened, and therefore the amount of bending deformation is suppressed to a small extent, and is directed toward the passenger compartment. The amount of displacement of is also reduced (see FIG. 9).

In the above description, the case where the side door 30 collides with the side door 30 at the center thereof, that is, the case where the external force is applied to the center of the side impact beam 31, the collision point is the front-back direction of the side door 30. In the case of the position biased to, the hole 33 of the two holes 33, 33 closer to the side of the side impact beam 31 where the amount of deformation is greater is opened, and the boot 34 on the side of greater deformation expands. It is advantageous from the viewpoint of protection.

Further, FIGS. 10 to 12 show a fourth embodiment of the door structure according to the present invention. Instead of the two independent boots provided in the third embodiment, the boots are integrally formed. 44, the same components as those in the third embodiment are designated by the same reference numerals, detailed description thereof will be omitted, and the following description will be made with reference to the drawings.

The side impact beam 41 mounted in the side door 40 of the vehicle is provided with gas injection holes 33, 33 on the side facing the door inner panel 30a near both ends of the steel pipe 31a cut into a predetermined size. The holes 33 and 33 are airtightly closed by a thin film 33a so that they can be easily perforated with a needle or the like. Also,
In the steel pipe 31a, needles 33b,
33b is erected, and the push bar 32 is bent in a V shape at the center so that the surface on which the needle 33b is erected is the inside.
The center portion is welded and attached to the center of the inner surface of the steel pipe, and the needles 33 are provided upright at both ends of the push bar 32.
b and 33b are arranged close to the inner sides of the holes 33 and 33, respectively. In addition, the steel pipe 31
A boot 44 having flexibility is airtightly attached to the outer periphery of a so as to cover almost the entire length except both ends.
Near the both ends of the boot 44, the holes 3 of the steel pipe 31a
On the outside of 3, 33, inflatable portions 44a, 44a, which are formed in advance so as to be easily inflated, are arranged.

At both ends of the steel pipe 31a, steel brackets 25 are attached to the mounting holes 25a by hermetically fitting the ends of the steel pipe 31a, respectively, and firmly connecting them by welding. A side impact beam 41 is configured by filling a non-combustible and harmless high-pressure gas such as nitrogen gas into a hollow portion of the steel pipe 31a from a gas filling valve 29 having a check function attached to one bracket 25. .

In the side impact beam 41 constructed as described above, brackets 25, 25 at both ends of the side door 40 are provided between the door outer panel 30a and the door inner panel 30b via stays 26, 26. The side doors 40 are attached to both ends of the vehicle body in the front-rear direction.

Next, the operation of this embodiment constructed as described above will be described in the case where another vehicle collides with a position deviated from the center of the side door on the side surface of the vehicle body. First, from the center of the side door 40, The removed door outer panel 30a is deformed, and this deformed door outer panel 30a
The side impact beam 41 is pressed by and is bent at a position biased to one end side (the left end side in FIG. 12).
When the side impact beam 41 is bent, one end (left end side in FIG. 12) of the push bar 32 attached inside is pushed, and the needle 3 erected at this end portion is pushed.
3b approaches the corresponding hole 33, pierces the thin film 33a blocking the hole 33, and breaks it. As a result, the high pressure gas filled in the steel pipe 31a is ejected from the hole 33. Then, the ejected gas is distributed so that the inside of the boot 44 is directed toward both ends, and the two inflated portions 44 at both ends are distributed.
4 a and 44a are instantly expanded.

In this way, the inflated portions 44a, 44a at both ends are
Since the high pressure gas is ejected from either one of the holes 33, 33 formed near both ends of the steel pipe 31a, both the inflating parts 44a, 44a can be inflated respectively.

Therefore, as in the case of the third embodiment, new support points are formed by the inflated boots 44, 44 at two positions in the middle of the side impact beam 41 whose both ends are supported by the bracket 25. As a result, the boots 44, 44 in which the side impact beam 41 in the middle of deformation expands are attached to the door inner panel 3.
0b and the side impact beam 41 are interposed, the span that causes bending deformation is shortened, and as a result, the amount of bending deformation is suppressed to a small amount, and the amount of displacement toward the passenger compartment is also reduced (Fig. 12).

In the above description, the case where the side door 40 collides with the side door 40 at the position deviated from the center thereof is explained. However, when the side door 40 collides with the side door 40 near the center thereof, the push bar 32 is pressed. 33b, 33b at both ends of the
Are holes 3 formed at two locations near both ends of the steel pipe 31a.
The high pressure gas ejected from the holes 33 and 33 respectively causes the two expansion parts 44a and
44a is directly filled and expanded, and the same effect as in the case of the third embodiment is obtained.

[0043]

As described above, the vehicle door structure of the present invention is provided with the gas generator in the side impact beam whose both ends are airtightly closed, and has a plurality of through holes formed in its beam peripheral wall. Since the boot having flexibility is provided outside the through hole so as to cover the outer circumference of the beam in an airtight manner, the boot expanded and hardened by being filled with the gas generated from the gas generator at the time of collision becomes a new supporting point. Therefore, the amount of bending deformation of the side impact beam can be suppressed to be small without increasing the weight and size of the side impact beam.

If high pressure gas is previously filled in the side impact beam whose both ends are airtightly closed, a hole is formed in the side impact beam at the time of collision, and this gas is ejected to inflate the boot, Since the hard and inflated boot serves as a new support point to support the side impact beam, the span of the side impact beam on which the bending moment acts is shortened, and the amount of bending deformation of the side impact beam is reduced, resulting in The amount of displacement toward the passenger compartment is also reduced. In addition, since devices and electric circuits that use electricity, such as collision sensors and inflators equipped with squibs, are not used, it is possible to prevent malfunctions such as malfunctions due to short circuits in wiring and malfunctions such as disconnection during collisions. You can

[Brief description of drawings]

FIG. 1 is a side view of a side impact beam in a first embodiment of an automobile door structure according to the present invention.

FIG. 2 is a cross-sectional plan view of a side door showing the door structure of the first embodiment.

3 is a cross-sectional plan view showing a state in which an external force due to a collision is applied to the side door of FIG.

FIG. 4 is a side view of a side impact beam in the second embodiment of the vehicle door structure of the present invention.

FIG. 5 is a cross-sectional plan view of a side door showing the door structure of the second embodiment.

6 is a cross-sectional plan view showing a state in which an external force due to a collision is applied to the side door of FIG.

FIG. 7 is a side view of a side impact beam in a third embodiment of the automobile door structure according to the present invention.

FIG. 8 is a cross-sectional plan view of a side door showing the door structure of the third embodiment.

9 is a cross-sectional plan view showing a state in which an external force due to a collision is applied to the side door of FIG.

FIG. 10 is a side view of a side impact beam in the fourth embodiment of the automobile door structure according to the present invention.

FIG. 11 is a cross-sectional plan view of a side door showing the door structure of the fourth embodiment.

12 is a cross-sectional plan view showing a state in which an external force due to a collision is applied to the side door of FIG.

FIG. 13 is a side view of an automobile door including a conventional side impact beam.

14 is a sectional view taken along line XIV-XIV in FIG.

FIG. 15 is a partially omitted side view of a conventional side impact beam.

[Explanation of symbols]

 10 Side Door 10a Outer Panel 10b Inner Panel 11 Side Impact Beam 12 Inflator 13 Through Hole 14 Boots 21 Side Impact Beam 23 Hole 23a Thin Film 23b Needle 29 Gas Filling Valve 32 Push Bar

Claims (2)

[Claims] 1. A door structure for an automobile, comprising a pipe-shaped side impact beam in the door between an outer door panel and a door inner panel, wherein both ends of the side impact beam are hermetically closed. It is supported and attached near both ends in the vehicle front-rear direction, and inside the hollow beam,
It is equipped with a gas generator that ignites and generates a large amount of gas when a collision with this side impact beam attachment position is detected. Furthermore, a plurality of through holes are formed in the outer peripheral wall of the beam, and outside of this through hole. , Expanded by the gas generated in the gas generator and ejected from the plurality of through holes,
A door structure for an automobile, characterized in that flexible boots that expand between the side impact beam and the door inner panel to form new support points for the side impact beam are provided in a contracted state. . 2. A door structure for an automobile, comprising a pipe-shaped side impact beam in a door between an outer door panel and a door inner panel, wherein both ends of the side impact beam are hermetically closed. The beam is supported and attached in the vicinity of both ends in the front-rear direction, and a through hole is formed in the beam outer peripheral wall, and the through hole is sealed with a closing member that can be easily opened. A needle-shaped member that is enclosed and faces the inside of the through-hole and that breaks the blocking member and ejects the enclosed gas when the side impact beam is deformed is further provided outside the through-hole. It expands due to the gas ejected from the through-holes and expands between the side impact beam and the door inner panel to expand the side impact beam. Door structure of a motor vehicle boot having flexibility for forming the the Do support point, characterized in that it is provided in a deflated state.