JP3226005B2 - Railcar side structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin plate structure using mutually intersecting frame members as a frame of an outer plate, and more particularly to a thin plate structure suitable for use as a side structure of a railway vehicle. It is.

[0002]

2. Description of the Related Art In order to increase the speed and energy saving of railway vehicles, it is important to reduce the weight of a vehicle structure.
BACKGROUND ART A side structure of a conventional railway vehicle is configured by integrally joining a thin outer plate to a thin frame structure by spot welding or the like in order to secure strength while reducing the weight. An example of such a side structure will be described with reference to FIGS. In FIG. 13, a plurality of vertical members 2 and a plurality of horizontal members 3 are arranged inside the outer plate 1 so as to intersect. A three-dimensional joint 4 is arranged at the intersection, and the outer panel 1, the vertical member 2, and the horizontal member 3
Are joined together. The vertical member 2 and the horizontal member 3 constitute a frame. The cross-sectional shape of the vertical member 2 and the horizontal member 3 is a hat shape, and the two flanges at the tips are
Is in contact with

As shown in FIG. 14, a hat type is a U-shaped U-shaped cross section composed of webs 2b, 3b and bottom surfaces 2c, 3c.
And a flange 2a, 3a provided at the end of the web of the U-shaped portion. At the intersection of the vertical member 2 and the horizontal member 3, the vertical member 2 is continuous in the vertical direction, and the horizontal members 3 and 3 are provided on both sides of the vertical member 2. That is, the vertical member 2 has priority.

[0004] The three-dimensional joint 4 is integrally formed three-dimensionally to join the vertical member 2 and the horizontal member 3 together. 3D joint 4 and flange 2 of vertical member 2 by spot welding 5A
a, and the outer plate 1 are connected, and the three-dimensional joint 4 and the member at the center of the vertical member 2 are connected by spot welding 5B. 3D joint 4 and flange 2 of horizontal member 3 by spot welding 6A
a, and the outer plate 1 are connected, and the three-dimensional joint 4 and the member at the center of the horizontal member 3 are connected by spot welding 6B. 2
Flange 2a of the vertical member 2 between the three solid joints 4, 4;
The flange 3a of the horizontal member 3 is joined to the outer plate 1 by a plurality of spot welds 7, respectively.

[0005] As shown in FIG.
The vertical member 2 is located near the web 2b. Therefore, the end of the horizontal member 3 overlaps the flange 2 a of the vertical member 2. For this reason, the height of the end of the horizontal member 3 is shorter by the thickness of the flange 2a of the vertical member.

Reference numeral 4 denotes a three-dimensional joint integrally formed for joining the frames, which is fixed to a vertical member by spot welding 5 and to a horizontal member by spot welding 6. The connection between the outer plate and the skeleton between the three-dimensional joints (d dimension) is performed by spot welding 7. In this case, since the outer plate side flanges of the lateral member 3 are continuously arranged, the pitch of the spot welding can be arbitrarily determined, but three plates of the outer plate 1, the frame members 2, 3 and the three-dimensional joint 4 are provided. The position of the lap spot weld 8 is restricted by the structure of the joint.

In the above-mentioned conventional structure, a blank portion 9 (see FIG. 16) surrounded by the longitudinal member 2 and the outer plate 1 which are preferentially passed is formed at the intersection of the frame, so that the vertical member has a horizontal member. When an axial force is applied from above, a discontinuous portion is likely to be generated in out-of-plane bending of the vehicle body side structure portion and transmission of the axial force of the lateral member 3, and when the load condition is severe, bending of the outer plate is likely to occur. There are drawbacks.

[0008] In addition, regarding the structural structure of railway vehicles, etc., see Japanese Utility Model Application Laid-Open No. 56-186183, "Pillar Structures in Railway Vehicles".
Also, there are known examples such as JP-A-59-186762 "Joint structure of frame". Japanese Utility Model Laid-Open No. 56-161853 aims to prevent poor transmission of axial force and decrease in bending rigidity due to discontinuous joints between columns and horizontal members. A pillar structure that reinforces the pillar and includes a reinforcing pillar that also serves as a lining plate and a fixture mounting material is shown. This known example does not mention prevention of local buckling of the skin.

Japanese Patent Application Laid-Open No. 59-186762 has a structure in which a skeleton and an outer plate are joined by a joining material. This known example is effective in preventing buckling of the outer plate. However, when the load condition becomes severe and the axial force of the transverse member increases, there is a problem that the adhesive has lower strength reliability than spot welding.

[0010]

In a conventional structure of a railway vehicle, a cross-shaped joint of a frame is provided with a hat-shaped vertical frame member which is preferentially inserted and an outer plate of a discontinuous portion surrounded by an outer plate. The transmitted axial force of the lateral member is transmitted only by the outer plate. Therefore, when the load condition is severe, there is a problem in the strength of the vehicle body, such as a local buckling phenomenon occurring in the outer plate of the relevant portion during out-of-plane bending of the vehicle body side structure portion or transmission of the axial force of the lateral member. there were. That is, in the above-described conventional structure, since the cross section of the vertical member is a hat shape, that is, a U-shaped cross section with one end opened,
The interval between the two U-shaped sides is likely to be reduced. Therefore, when an axial force is applied to the vertical member from the horizontal member, discontinuous portions are likely to be generated in the out-of-plane bending of the vehicle body side structure and the transmission of the axial force of the horizontal member. Has the disadvantage that it is easily bent.

An object of the present invention is to provide a side structure for a vehicle having a strength capable of withstanding a severe load condition.

Another object of the present invention is to provide a side structure for a vehicle which is lightweight and has sufficient strength to prevent buckling of an outer plate.

[0013]

SUMMARY OF THE INVENTION The present invention provides a vertical member and a horizontal member constituting a frame member, a joint for integrally connecting the vertical member and the horizontal member, and a thin outer member fixed to the frame member. consists of a plate, each <br/> of the longitudinal member and transverse member comprises a member of a hat-shaped cross section and a pair of web and flange surface extending from the respective web edge, the furan
In a side structure of a railway vehicle, which is spot-welded to the outer plate , at a portion surrounded by both webs of the one frame member of the frame member and the outer plate , and intersects with the other member of the frame member. Where the reinforcing plate is located,
The reinforcing plate has a cross section along the longitudinal direction of the one frame member.
L-shape is a combination of vertical and flange parts
Portion of the reinforcing plate in a direction orthogonal to the longitudinal direction.
Both end faces are welded to the two webs of the one frame member.
The flange portion of the reinforcing plate is spot fused to the outer plate.
And the one of the frame members is
Holes for spot welding the
, Is characterized.

[0014]

Another feature of the present invention is that in the side structure of the railway vehicle, the reinforcing plate has an L-shape in which a cross-sectional shape along a longitudinal direction of the hat-shaped frame member is a combination of a vertical portion and a flange portion. An end portion of the vertical portion is connected to the two webs of the skeleton member, and the flange portion is connected to the outer plate by spot welding.
Another feature of the present invention is that, in the side structure of the railway vehicle, the reinforcing plate has an L-shape in which a cross-sectional shape along a longitudinal direction of the hat-shaped skeleton member extends to a U-shaped base portion and both sides thereof. A flange portion of a mold, wherein both end surfaces of the base portion are respectively connected to the two webs of the framing member, the flange portion is parallel to a bottom surface of the base portion, and the flange portion is It is that it is connected to the outer plate by spot welding.

Another feature of the present invention is that, in the side structure of the railway vehicle, the reinforcing plate has a cross-sectional shape along a longitudinal direction of the hat-shaped frame member, which is a combination of a base portion and webs on both sides thereof. It is U-shaped, the webs on both sides being respectively connected to both webs of the framing member, and the base being connected to the outer plate by spot welding.

According to the present invention, by arranging a reinforcing plate in a U-shaped section having a U-shaped cross section at a joint portion of a frame member having a hat-shaped cross section, the reinforcing plate functions as a tension member. Since the reinforcing plate and the outer plate are combined, it is possible to provide a side structure that prevents buckling of the outer plate and can withstand severe load conditions.

Further, according to the present invention, since the flange portion is connected to the outer plate by spot welding, the distance L between fixing the outer plate can be shortened. Therefore, the buckling strength due to the out-of-plane bending of the outer plate and the axial force transmission load can be improved.

By adopting the present invention to a side structure of a railway vehicle, means for forming a framework of a lightweight thin plate body structure can be used to prevent distortion of an outer plate at the time of manufacturing the structure and to buckle the outer plate when the load condition is severe. It is effective in preventing. Further, since the connection to the reinforcement of the outer plate can be performed by spot welding in the same manner as other frames, there is no sense of incongruity in appearance due to the addition of the spot welding.

When the load condition is more severe, a reinforcing plate having an appropriate thickness is added in advance to the outer plate side of the reinforcing plate and connected to the outer plate, so that the buckling can be further increased without increasing the weight. Strength can be improved.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a drawing in which a side structure constituting a side surface of a railway vehicle is viewed from the inside. E is a space for the entrance of the passenger. A plurality of vertical members 2 and a plurality of horizontal members 3 are arranged inside the side plate 1 so as to intersect. A three-dimensional joint 4 is arranged at the intersection, and the three members of the outer plate 1, the vertical member 2, and the horizontal member 3 are integrally connected. Vertical member 2 and horizontal member 3
Constitute a skeleton.

In the present invention, the structure shown in FIGS. 2 to 4 is adopted as the structure of the three-dimensional joint of the side structure of the vehicle. In the figure, the cross-sectional shapes of the vertical member 2 and the horizontal member 3 are hat-shaped, and two flanges at the tips are in contact with the outer plate 1. As described above, the hat type includes a U-shaped section having a U-shaped cross section including a pair of webs and a bottom surface.
Refers to the shape consisting of flanges provided at the end of the web of the shape.

The three-dimensional joint 4 is a joint for connecting the two frame members 2 and 3 and is composed of an outer plate side flange 4a, an indoor side flange 4b, and a web 4c connecting the two flanges. The three-dimensional joint 4 is fixed to the vertical member 2 by spot welding 5 and to the horizontal member 3 by spot welding 6. The joint between the outer plate 1 and the skeleton between the three-dimensional joints (d dimension) is performed by spot welding 7. In addition, the joint between the outer plate, the frame member and the three-dimensional joint of the three-dimensional joint is performed by spot welding 8.

In the present invention, the reinforcing plate 10 having the flange surface 10a which is flush with the flange surface 2a on the outer plate side of the vertical member 2 is previously joined to the U-shaped portion of the vertical member 2. At this time, the reinforcing plate 10 is disposed at a position surrounded by the vertical member 2 and the outer plate 1 and at a position on a parallel line crossing the horizontal member 3. That is, the reinforcing plate 10 exists in a range L2 on an extension of the end of the flange 3a of the horizontal member 3. As shown in FIG. 2 and the like, the upper and lower ends of the reinforcing plate 10 may protrude vertically from the range L2 of the flanges 3a, 3a. Then, the flange surface 10 of the outer plate 1 and the reinforcing plate 10
a are joined by spot welding 11 and 12.

Generally, a buckling limit stress σcr of a flat plate as shown in FIG.

[0026]

(Equation 1)

Here, E: modulus of longitudinal elasticity of a flat plate ν: Poisson's ratio t: plate thickness a: length of a long side of a rectangle b: length of a short side of a rectangle K: stress distribution, peripheral conditions, ratio of length to length a The coefficient is determined by / b, and generally, K decreases as a / b decreases.

In the above equation, when t and b are constant, K becomes larger as a becomes smaller, and the buckling limit stress σcr becomes larger. From this, it can be seen that when the plate thickness t is constant, buckling is less likely to occur as the fixed distance (long side length a) is smaller.

In view of the above, the present invention is to fix the outer plate to the frame members 2 and 3 by spot welding at multiple points including on the flange surface 10a of the reinforcing plate 10.

The manufacturing state of the three-dimensional joint of the side structure of the vehicle according to the present invention will be described with reference to FIGS. FIG. 6 is a perspective view of the reinforcing plate 10 according to one embodiment of the present invention. Reinforcement plate 10
Has flange surfaces 10a, 10a in contact with the outer plate 1, a bottom surface 10c in contact with the bottom surface 2c of the vertical member 2, and side edges 10b in contact with the web surfaces 2b, 2b of the vertical member 2.

As shown in FIG. 7, the vertical member 2 has flange surfaces 2a, 2a. The reinforcing plate 10 is
b is firmly fixed to the web surfaces 2b, 2b of the vertical member 2 by welding 15.

FIG. 8 is a perspective view of the horizontal member 3 in which the three-dimensional joint 4 is combined. The horizontal member 3 has flange surfaces 3a, 3a.
And a bottom surface 3b and webs 3c and 3c therebetween.
The three-dimensional joint 4 is fixed to the outer plate side flanges 4a, 4a and the indoor side flange 4b, respectively.

FIG. 9 is a perspective view of a combination of a skeleton including the vertical member 2 and the horizontal member 3. The reinforcing plate 10 is disposed at a position surrounded by the vertical member 2 and the outer plate 1 and at a position on a parallel line crossing the horizontal member 3. The sides 10b of the reinforcing plate 10 are fixed to the web surfaces 2b of the vertical member 2 by welding 15 in advance.

The flange surface 2a on the outer plate side of the vertical member 2
Flange surfaces 10a, 10aa of the reinforcing plate in the same plane as
The outer plate 1 is joined by spot welding. That is,
When the outer plates 1 and 1a are combined with the frame structure, the outer plates 1 are spot-welded 11 and 12 to form the flange surfaces 10aa and 10aa.
Bind to 10a. FIG. 14 is a perspective view of the structure to which the outer plate 1 is attached.

Numeral 11 indicates two spot weldings of the outer plate 1a and the flange surface 10aa of the reinforcing plate 10. 12
Indicates spot welding of three sheets of the outer plates 1 and 1a and the flange surface 10b of the reinforcing plate 10. Reference numeral 14 denotes one electrode for spot welding, and the bottom 2c of the vertical member 2 so that the electrode 14 can be inserted into the back surface of the flanges 10aa, 10a.
Are provided with holes 16,16. Spot welding 11-1
2 is the distance L2 between the flanges 3a-3a of the horizontal member.
It is slightly smaller than that. The spot welding position 12 is a portion where the outer plate 1a and the outer plate 1 are overlapped and joined. The outer plate 1a is located outside the outer position 1. For this reason, a step 13 is provided at the outer position 1 a by the thickness of the outer plate 1. This is commonly referred to as a breach.

By adopting such a structure, it is possible to obtain a structure in which the outer plate 1 does not buckle even under severe load conditions. That is, the distance L between the fixing points of the outer plate 1 by spot welding can be shortened, for example, to 比 べ, as compared with the conventional case in which the outer plate 1 is fixed by the flange portion on the outer plate side of the framed vertical member 2. Therefore, it is possible to improve the buckling strength due to the out-of-plane bending of the outer plates 1 and 1a and the axial force transmission load.

Conventionally, the webs 2b and 2b
b, the overlapping portion of the outer plate 1 and the outer plate 1a (that is, near the end surfaces of the outer plates 1 and 1a) is not spot-welded. Therefore, when an axial force is applied from the lateral member 3, the outer plates 1 and 1a at this portion (near the end face) are easily buckled as is well known. The end face is more likely to buckle. But,
In the above embodiment, since the outer plates 1 and 1a of the overlapping portion are fixed to the flange surfaces 10a and 10aa of the reinforcing plate 10 fixed to the vertical member 2 by spot welding 12 and 11, buckling can be prevented. is there.

The structure of the three-dimensional joint of the side structure of the vehicle according to the present invention is used as a means for forming a framework of a lightweight thin plate body structure, in order to prevent the distortion of the outer plate at the time of manufacturing the structure and to seat the outer plate when the load condition is severe. It is effective to prevent buckling. Further, since the connection to the reinforcement of the outer plate is performed by spot welding as in the case of other frames, there is no sense of incongruity in appearance due to the addition of the spot welding.

The reinforcing plate 10 of the joint portion is firmly fixed in advance to the vertical member 2 by welding 15, and the axial force of the horizontal member 3 is relatively increased via the reinforcing plate 10 and the outer plate 1 connected thereto. Can be smoothly transmitted to the horizontal member 3. In addition, by joining the reinforcing plate 10 and the outer plate 1 by spot welding 11 and 12, the distance between the fixing of the outer plates can be shortened, so that the buckling strength of the outer plate is greatly improved.

The reinforcing plate 10 has a flange 10b, and the height from the flanges 10a, 10aa to the bottom 10c is preferably equal to the height from the inside of the bottom 2c of the bone member 2 to the flange 2a. According to this, the reinforcing plate 10 is connected to the bone member 2.
When it is inserted into the inside, the surfaces of the flanges 10a and 10aa and the surface of the flange 2a are at the same position, so that a special positioning jig is not required and the welding operation can be simplified.

The position of the weld 15 of the reinforcing plate 10 is
This is the position facing c. Since welding is not performed at the positions of the flanges 2a and 10a, it is not necessary to cut a weld bead at that portion.

Since the position of the weld 15 may be a position close to the flange 2a, the welding operation can be simplified.

The interval between the webs 10b-10b of the reinforcing plate 10 is equal to the interval between the webs 3b-3b of the horizontal member 3.
The width of the flanges 10a, 10a is the same as the width of the flanges 3a, 3a. Therefore, the vertical member 2 and the like are prevented from being deformed, and the axial force of the horizontal member 3 is applied to the horizontal member 3 via the vertical member 2.
Can be transmitted to

When the load condition is more severe, a reinforcing plate having an appropriate thickness may be added in advance to the outer plate side of the reinforcing plate 10 and connected to the outer plate 1 without increasing the weight. Buckling strength can be improved.

The present invention is not limited to railcars, and is a structure using crossing members having a cross section composed of an outer plate side flange, an indoor side flange, and a web connecting both flanges, as a frame of the outer plate. The present invention can be applied to a structure for preventing buckling of an outer plate in which a connecting portion of members becomes discontinuous.

In order to apply the present invention, it is sufficient that at least one of the vertical member 2 and the horizontal member 3 has a hat-shaped cross section. What is necessary is just to fix a reinforcement board to the framework member of a hat-shaped cross section. Further, the joint portion may be not only a three-dimensional joint but also a planar joint.

As described above, according to the embodiment of the present invention, it is possible to provide a side structure capable of withstanding a severe load condition by arranging the reinforcement at the member connecting portion in the thin body frame structure. That is, 1) The reinforcing plate 10 provided on the joint constituting portion of the vertical member 2 can be made as a single item and incorporated into the skeleton member at the time of the component.

2) Since the reinforcing plate 10 is disposed on the extension of the horizontal member, the transmission of the axial force of the horizontal member is performed smoothly.

3) The outer plate facing the center of the conventional joint structure is formed by spot welding 8 as shown in FIG.
And the horizontal member 3, the distance between the fixed outer plates is L
, And could not be further reduced in structure. As in the present invention, the reinforcing plate 10 is disposed and the outer plate is spot-welded 1
By connecting the reinforcing plate 10 to the reinforcing plate 10 by using the joints 1 and 12, the distance between the fixing of the outer plates can be shortened, so that the buckling strength of the joint outer plate can be improved.

The embodiment shown in FIG. 11 is another embodiment of the reinforcing plate 10, in which two short C-shaped (channel-shaped) reinforcing plates 10A and 10B are used in combination, and the respective webs 10Ab and 10Bb are used. This is obtained by welding 15, 17 to the web 2b of the vertical member 2. Flanges 10Aa, 10B
“a” corresponds to the flanges 10aa and 10a.

The embodiment shown in FIG. 12 is another embodiment of the reinforcing plate 10, in which a reinforcing plate 10C which is long in the longitudinal direction of the vertical member 2 is used, and both ends in the longitudinal direction are bent to form a flange 10Cc.
I have to. The flange 10Cc is welded to the web 2b.
are doing. The flange 10Ca between the flanges 10Cc and 10Cc is welded 15 to the flange 2a. The bead of the welded portion 18 is cut and flattened.

When the horizontal member 3 has priority in relation to the vertical member, the reinforcing plate 10 is installed in the space of the horizontal member 3.

[0053]

According to the present invention, by arranging a reinforcing plate at a member connecting portion in a body frame structure using a thin plate,
A side structure for a vehicle that can withstand severe load conditions can be provided.

Further, since the reinforcing plate is disposed on an extension of another member intersecting one of the longitudinal members or the transverse members constituting the frame member, the axial force of the other member is smoothly transmitted. Done in

Further, since the distance between the fixing positions of the outer plate can be made shorter than before, the buckling strength of the joint outer plate can be improved.

[Brief description of the drawings]

FIG. 1 is a main part front view showing a general configuration of a skeleton of a side structure of a vehicle to which the present invention is applied.

FIG. 2 is a front view of a joint structure according to an embodiment of the present invention, which is used as a joint portion of the cross-frame shown in FIG.

FIG. 3 is a sectional view taken along line DD of FIG. 2;

FIG. 4 is a sectional view taken along line EE of FIG. 2;

FIG. 5 is a view showing a calculation model of a buckling limit stress of a flat plate.

FIG. 6 is a perspective view of a reinforcing plate in the embodiment of FIG.

FIG. 7 is a perspective view of a skeleton vertical member to which a reinforcing plate is attached in the embodiment of FIG. 2;

FIG. 8 is a perspective view of a lateral member combined with a three-dimensional joint in the embodiment of FIG. 2;

FIG. 9 is a perspective view showing a state where a vertical member and a horizontal member are combined in the embodiment of FIG. 2;

FIG. 10 is a perspective view of a structure in which the skin is attached to the skeleton in the embodiment of FIG. 2;

FIG. 11 is a perspective view of a reinforcing plate according to another embodiment of the present invention.

FIG. 12 is a perspective view of a reinforcing plate according to another embodiment of the present invention.

13 is used as a joint part of the cruciform skeleton of FIG. 1,
It is a front view showing an example of the conventional joint structure.

14 is a perspective three-dimensional view of a part of the right half of FIG. 13;

FIG. 15 is a sectional view taken along line BB of FIG. 13;

FIG. 16 is a sectional view taken along line CC of FIG. 13;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Outer plate, 2 ... Frame vertical member, 3 ... Frame horizontal member, 4 ... Solid joint, 5,6,7,8 ... Spot welding, 9 ... Vertical member blank portion, 10,17,18 ... Reinforcement plate, 11 ... Spot welding of two sheets of reinforcement of outer plate, 12: Spot welding of three sheets of reinforcement of outer panel, 13 ... Behind the joint of outer plate, 14 ... Electrode, 15 ... Welding, 16 ... Through hole.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-54431 (JP, A) JP-A-7-172303 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B61D 17/08

Claims (6)

(57) [Claims] 1. A vertical member and a horizontal member constituting a frame member;
A joint for integrally connecting the vertical member and the horizontal member,
It consists of a thin outer skin fixed to the frame member, the vertical
Each of the member and the lateral member has a hat-shaped cross-sectional shape having a pair of webs and a flange surface extending from each web end.
The flange is spot welded to the outer plate
In the side structure of the railway vehicle , a reinforcing plate is disposed at a portion surrounded by both webs and the outer plate of one of the framing members of the framing member and at a position intersecting with the other member of the framing member. The reinforcing plate is cut along the longitudinal direction of the one skeleton member.
L-shape where the surface shape is a combination of a vertical part and a flange part
The reinforcing plate in a direction orthogonal to the longitudinal direction, including a mold portion
Are welded to the two webs of the one frame member.
Are, the flange portion of the reinforcing plate is spot welded to the outer plate
And the flange portion of the reinforcing plate and the outer
A side structure of a railway vehicle, wherein a hole for spot welding a plate is provided . 2. The side structure of a railway vehicle according to claim 1, wherein said reinforcing plate has a U-shaped section and an L-shaped section extending on both sides thereof along a longitudinal direction of said one frame member. Wherein the distance between the sides on both sides of the U-shaped part is substantially the same for both webs of the other skeleton member, and the sides on both sides of the U-shaped part are The side structure of a railway vehicle, wherein the flanges are connected to the outer plate by spot welding, respectively. 3. The side structure of a railway vehicle according to claim 1, wherein the reinforcing plate has a U-shape in which a cross-sectional shape along a longitudinal direction of the one frame member is a combination of a base portion and webs on both sides thereof. A side structure of a railway car, wherein the webs on both sides are respectively connected to both webs of the one skeleton member, and the base portion is connected to the outer plate by spot welding. 4. The side structure of a railway vehicle according to claim 2, wherein a plurality of said U-shaped reinforcing plates are arranged along a longitudinal direction of said one frame member. Side structure of the rolling stock to be used. 5. The side structure of a railway vehicle according to claim 3, wherein a distance between the two U-shaped webs of the reinforcing plate is substantially the same as a distance between the two webs of the other frame member. A side structure of a railway vehicle, characterized in that: 6. The side structure of a railway vehicle according to claim 1, wherein one of the frame members on which the reinforcing plate is disposed is the vertical member.