JP2000025646A - Cross member and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a light cross member with a low cost by providing a first member having a first web, formed integrally with a first flange, with a shape entered in a blank and a second member having a second web fixed to one end of the first web. SOLUTION: A first member 50 has a first flange 52 for tightening both ends 52a of a longitudinal direction to a side member and a first web 54 formed integrally with the first flange 52. A recessed blank 52c is formed on one end of the first flange 52. The shape of a second member 60 is same as that of the first member 50 and both ends 62a of the longitudinal direction are tightened to the side members and the second member has a second flange 62 facing together with the first flange 52 and a second web 64 formed integrally with the second flange 62. One end of the width direction of the second web 64 is tightened to one end of the width direction of the first web 54. Thereby, the light cross member with a low cost can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cross member used for vehicles such as medium-sized and large-sized trucks and buses, and a method for manufacturing the same.

[0002]

2. Description of the Related Art A frame called a ladder-shaped frame is generally used as a frame (vehicle frame) for a medium or large truck or bus. This ladder-shaped frame usually has two side members (longitudinal members) extending at predetermined intervals in the longitudinal direction of the vehicle, and a plurality of side members fixed to the side members at both longitudinal ends by rivets or welding. And a cross member (horizontal member).

An example of a conventional ladder frame will be described with reference to FIG.

FIG. 7 is a perspective view showing an example of a conventional ladder frame.

The ladder-shaped frame 10 has two groove-shaped side members 12 and 14 extending at a predetermined distance in the longitudinal direction of the vehicle (the direction of arrow A). The cross section of these two groove-shaped side members 12, 14 is in the shape of a "U".
It is sometimes called a shaped side member. The channel-shaped side members 12, 14 are composed of webs 12a, 14a and flanges 12 integrally formed with the webs 12a, 14a.
b, 14b.

[0006] The two grooved side members 12 and 14 are provided with the grooved cross member 1 and the grooved side members 12 and 14.
6 are connected by being fixed at both ends 16b. Although only one grooved cross member 16 is shown in FIG. 7, a plurality of grooved cross members 16 are usually used. The cross-section of the groove-shaped cross member 16 is “U”.
, The web 16a and the web 16a
Two flanges 1 integrally formed with each other and facing each other
6b. Although the groove-shaped cross member 16 is shown in FIG. 7 as the cross member, a Z-shaped cross member having a “Z” cross section may be used.

Referring to FIGS. 8 and 9, a grooved cross member will be described as an example of a cross member.

FIG. 8 is a perspective view showing a grooved cross member called a gusset type, and FIG. 9 is a perspective view showing a grooved cross member called an integral type.

A groove-shaped cross member 18 called a gusset type shown in FIG. 8 has a cross member body 20 having a U-shaped cross section and a flange 2 of the cross member body 20.
The gusset 22 is composed of four gussets 22 fixed to two at both ends in the longitudinal direction of Ob. The cross member body 20 and the gusset 22 are fastened with rivets 24. FIG.
Is bent, and the bent portion 22a is fastened to the webs 12a, 14a of the channel-shaped side members 12, 14 (see FIG. 7) by rivets. Thus, the web 1 of the grooved side members 12, 14 is
The type fastened to 2a, 14a is called a web fastening type. Note that the gusset 22 is not bent and the flanges 12 of the grooved side members 12 and 14 (see FIG. 7) are
Also, a flange fastening type which is fastened with rivets to b and 14b is used. Further, instead of using rivets, they may be fixed by bolts or welding.

A groove-shaped cross member 28 called an integral type shown in FIG. 9 has a U-shaped cross section.
An integrally molded web 28a and two flanges 28
b. The two flanges 28b face each other, and three rivet holes 28c are formed at both ends in the longitudinal direction. A rivet (not shown) is passed through the hole 28c to insert the groove side member 12,
The groove-shaped cross member 28 is fastened to the flanges 12b and 14b of the 14 (see FIG. 7). This type is called a flange fastening type. The central portion of the two flanges 28b of the groove-shaped cross member 28 is thinner than both end portions for the reason described later. In addition, two flanges 28b
Are bent at both ends to form rivet holes in the bent portions, and rivets (not shown) are passed through the holes to form webs 12a, 14a of the grooved side members 12, 14.
There is also used a so-called web fastening type for fastening the grooved cross member 28 to the web.

As described above, the groove-shaped cross member includes:
There are a gusset type which is fixed to the side member via a gusset, and an integrated type which is directly fixed to the side member. Further, these two types include a flange fastening type which is fastened to a flange of the side member. And a web fastening type which is fastened to the web of the side member.

By the way, in any of the above-mentioned grooved cross members, the central portion in the longitudinal direction is thinner than both ends in the longitudinal direction of the flange. In the gusset-type grooved cross member 18 (see FIG. 8), a gusset 22 having a width larger than the width of the flange 20b of the cross member body 20 is used, and the center in the longitudinal direction is made thinner than both ends in the longitudinal direction of the flange. ing. On the other hand, in the integral type grooved cross member 28 (see FIG. 9), the central portion 28d of the flange portion 28 is removed to form a blank portion (nothing portion), and is longer than both ends in the longitudinal direction of the flange. The center of the direction is narrower.

As described above, the reason why the central portion in the longitudinal direction is made thinner than both ends in the longitudinal direction of the flange of the groove-shaped cross member is that when a force acts on the groove-shaped cross member,
By bending the central portion in the longitudinal direction of the flange, the stress acting on the rivet (not shown) fastened to the side members 12, 14 (see FIG. 7) is reduced. In addition, the area of both ends in the longitudinal direction of the flange is increased to increase the number of rivets for fastening the side members 12, 14 and the cross members 18, 28, or to increase the number of rivets.
One of the reasons is to increase the area of welding with No. 14. Note that, even in a Z-shaped cross member having a “Z” cross section, the central portion in the longitudinal direction is thinner than both ends in the longitudinal direction of the flange for the same reason as described above.

Referring to FIG. 10, an example of a method of manufacturing the integral type grooved cross member 28 shown in FIG. 9 will be described.

FIG. 10A is a schematic diagram showing a punching line when punching a long material, and FIG. 10B is a schematic diagram showing a flat plate obtained by punching a long material. .

When manufacturing the groove-shaped cross member 28, as shown in FIG.
Punching a plate-like long material 30 having a width equal to the length of
And a flat plate 3 as shown in FIG.
6 are manufactured. This single flat plate 36 is
By bending along the line 6a, the groove-shaped cross member 28 shown in FIG. 9 is manufactured. When the long material 30 is punched to obtain the flat plate 36, an elliptical scrap 34 is generated because the central portion in the longitudinal direction of the flange 28b is made thinner than both ends in the longitudinal direction for the above-described reason.

[0017]

As described above, there are two types of ladder-type frame cross members used for medium-sized and large-sized trucks and buses.

Gusset type cross member 18 (FIG. 8)
4), there is a problem in that four gussets 22 are used for one cross member 18 and the number of parts is accordingly large. In addition, since the overlap margin between the cross member body 20 and the gusset 22 is required, there is a problem that the weight increases accordingly. Further, there is a problem that it takes time to fix the four gussets 22 to the cross member body 20.

On the other hand, the integrated cross member 28 does not use a gusset, so that there is no increase in weight or the number of parts. However, an oval scrap 34 (see FIG. 10) is generated at the time of manufacturing, and the material is not used. There is a problem that the yield is lowered and the cost is increased. It is said that the amount of the scrap corresponds to about 30% of the long material 30.

In view of the above circumstances, an object of the present invention is to provide a lightweight and low-cost cross member and a method of manufacturing the same.

[0021]

According to the present invention, there is provided a cross member comprising two vehicle side members extending parallel to each other at a predetermined distance and having both longitudinal ends fixed thereto. (1) a first flange having the both ends and a concave blank portion formed at one end in the width direction; and a longitudinal direction from the other end opposite to the one end in the width direction. A first member having a first web formed integrally with the first flange and entering the blank portion; (2) a second flange having the same shape as the first flange, and the first web; And a second end in which one end in the width direction is fixed to one end in the width direction of the first web.
A second member having a web is provided.

Here, it is preferable that each of the first and second webs has (3) the same shape as the blank portion.

[0023] The first web and the second web are: (4) one in which the center portions in the width direction or the center portion and the tip portion are fixed instead of one end portions in the width direction. It is preferred that

According to the present invention, there is provided a cross member manufacturing method for manufacturing a cross member in which both longitudinal ends are fixed to two vehicle side members extending parallel to each other at a predetermined interval. In the method, (5) a first cutting line extending in the width direction of the long material at both ends in the width direction of the long material having a width substantially equal to the length of the cross member. At the center of the long material in the width direction, the long material is cut so as to form a bow-shaped or mountain-shaped second cutting line continuous with the first cutting line. A cutting step of forming a plurality of flat plates having a square shape and having a curved shape at the center in the width direction of the long material. (6) The bending of the flat plates with respect to a line extending in the longitudinal direction of the flat plates. Part of the shape Bending step of forming a partial cross member having an L-shaped cross section by bending. (7) A fixing step of fixing the distal ends of the curved portions of the two partial cross members. It is assumed that.

Here, the fixing step is as follows: (8) Instead of fixing the end portions of the curved portions of the two partial cross members, instead of fixing the center portions of the curved portions, It is preferable that the center part and the tip part are fixed.

[0026]

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

FIG. 1 is a perspective view showing an embodiment of the cross member of the present invention.

The cross member 40 has a U-shaped cross section, is called a groove-shaped cross member, and includes a first member 50 and a second member 60 having the same shape. As will be described later, the first and second members 50 and 60 are integrally formed by fastening one ends of the first and second webs 54 and 64 in the width direction with rivets 42. Further, in FIG. 1, one end portions of the first and second webs 54 and 64 in the width direction are fastened to each other.
Alternatively, the central portion in the width direction and one end may be fastened. By changing the fastening position in this manner, the width of the web of the cross member 40 can be changed, and cross members having various web widths can be easily manufactured.

The first member 50 is in the longitudinal direction (the direction of arrow B).
The both ends 52a of the side members 12 and 14 (see FIG. 7)
And a first web 54 molded integrally with the first flange 52. A plurality (three in this case) of rivet fastening holes 52b are formed in both end portions 52a of the first flange 52, respectively. The portion where the hole 52b is formed is bent substantially at a right angle, and is configured to be fastened to the webs 12a and 14a of the side members 12 and 14 (see FIG. 7) by rivets.

The width direction of the first flange 52 (arrow B)
(In the direction perpendicular to the plane) has a concave blank portion 52c
Are formed. The first web 54 extends in the direction of arrow B from the other end opposite to the one end, and has a shape that enters the blank portion 52c. Therefore, the blank portion 52c and the first web 54 have the same shape in conformity with each other.

The second member 60 has the same shape as the first member 50. Both ends 62a in the longitudinal direction (the direction of arrow B) are fastened to the side members 12, 14 (see FIG. 7). Facing second flange 62 and the second
It has a second web 64 integrally formed with the flange 62. A plurality (three in this case) of rivet fastening holes 62b are formed in both end portions 62a of the second flange 62, respectively. The portion where the hole 62b is formed is bent substantially at a right angle, and is configured to be riveted to the webs 12a and 14a of the side members 12 and 14 (see FIG. 7).

Further, one end of the second web 64 in the width direction is fastened to one end of the first web 54 in the width direction by the rivet 42, whereby the first member 50 and the second member 60 are connected.
And are united. A concave blank portion 6 is provided at one end of the second flange 62 in the width direction (the direction perpendicular to the arrow B).
2c is formed. The second web 64 extends in the direction of arrow B from the other end opposite to the one end, and has a shape that enters the blank portion 62c. Therefore, the blank portion 62c and the second web 64 have the same shape in conformity with each other.

Here, the strength of the portion where the one ends of the first and second webs 54 and 64 are riveted together will be examined.

The portion fastened with the rivets corresponds to the center of the cross member 40 in the width direction of the web. When a force acts on the cross member 40, the central portion in the width direction of the web becomes a neutral axis (a portion where a lower stress acts than other portions), so that the rigidity and durability of the cross member 40 do not decrease.

Referring to FIG. 2, cross member 40 of FIG.
Will be described.

FIG. 2A is a plan view showing a long material used as the material of the cross member 40, and FIG. 2B is a plan view showing a flat plate obtained by cutting the long material.

In order to manufacture the cross member 40, first, a plate-like long material 70 having a width equal to the length of the cross member 40 is prepared. It is more convenient to use the long material 70 wound in a coil shape. Also, here
The length of the cross member 40 refers to the first and second flanges 5.
The length includes both the bent end portions 52a and 62a of the cross member 40, and is longer than the actual length of the cross member 40 by the length of the both end portions 52a and 62a.

While feeding the long material 70 in the direction of arrow C, the long material 70 is cut (or punched) along a cutting line 72 using a known cutting device. The cutting line 72 is continuous with a first cutting line 72a extending in the width direction of the long material 70 at both ends in the width direction of the long material 70 and a first cutting line 72a at the center in the width direction of the long material 70. And a second cutting line 72b in the shape of a bow or a chevron. By cutting the long material 70 along the cutting line 72, the flat plate 8 shown in FIG.
A plurality of 0s are formed. As shown in (b), the flat plate 80 has a square shape at both ends 82 in the longitudinal direction (the width direction of the long member 70) of the flat plate 80, while a curved shape at the central portion 84 in the longitudinal direction of the flat plate 80. Or it has an arcuate shape.

The central portion 84 in the longitudinal direction of the flat plate 80 obtained as described above is connected to a line 86 extending in the longitudinal direction of the flat plate 80.
Or, bend about 90 ° near the border. As a result, a partial cross member having an L-shaped cross section is formed. Further, both ends 82 in the longitudinal direction of the flat plate 80 are bent by about 90 ° at a line 88 extending in the width direction of the flat plate 80. Thereby, the first and second members 50, 50 shown in FIG.
60 are formed. Regarding the order of bending at and near the lines 86 and 88, either may be bent first or the lines may be bent simultaneously. Although the step of forming the rivet holes 82a and 84a is omitted here,
The holes 82a and 84a may be formed before or simultaneously with the cutting of the long material 70, or the holes 82a and 84a may be formed in the state of the flat plate 80.

Thus, the first and second members 50, 6
0 (see FIG. 1), and the first and second webs 54, 6
The first and second members 50 and 60 are arranged such that the first and second flanges 52 and 62 are located on the same side with respect to the first and second webs 4, and one ends of the first and second webs 54 and 64 are riveted together. To conclude. That is, the tips of the curved portions of the two partial cross members are fastened with rivets. Thus, the cross member 40 shown in FIG. 1 is manufactured.
Here, one ends of the first and second webs 54 and 64 are fastened with rivets, but bolt fastening, spot welding,
It may be fixed by arc welding, laser welding, or the like.

As described above, the first and second members 5
When the cross member 40 is manufactured by forming 0 and 60, the blank portions 52c and 62c of the first and second members 50 and 60 are formed.
Correspond to the first and second webs 54 and 64. Therefore, in manufacturing the cross member 70 from the long material 70, scraps are removed except for holes 82a and 84a for rivets, mounting holes for other components to be processed as necessary, and holes for weight reduction. Does not occur. As a result, the yield of the material is almost 100%, and the cross member can be manufactured at low cost.

Also, since the gusset 22 (see FIG. 8) is directly fixed to the side members 12, 14 (see FIG. 7) without using the gusset 22, the number of parts can be reduced, and furthermore, no overlap with the gusset is required. And it can be made lighter. Furthermore, since the operation of fastening the gusset is not required, the number of operation steps can be reduced accordingly. Specifically, for example,
When the cross member 40 of FIG. 1 is used as a cross member of a 6-ton medium-sized truck, the material cost can be reduced by about 20 kg per vehicle as compared with the one-piece cross member 28 shown in FIG. In addition, since about 5 cross members of this type are used in a medium truck of 4 to 6 tons, when the cross member 40 of FIG. 1 is used, the gusset type cross member 18 shown in FIG. Than about 15 parts per vehicle.

Referring to FIG. 3, a second embodiment of the cross member of the present invention will be described.

FIG. 3 is a perspective view showing a cross member according to the second embodiment.

The cross member 90 has a U-shaped cross section and is called a groove-shaped cross member, and includes a first member 100 and a second member 110 having the same shape. In the first and second members 100 and 110, one ends of the first and second webs 104 and 114 in the width direction are fastened with rivets 42 to be integrated.

In the first member 100, both end portions 102a in the longitudinal direction (the direction of arrow B) have side members 12, 14 (FIG. 7).
1), and the first web 10 integrally molded with the first flange 102.
Four. Both ends 102a of the first flange 102
Are formed with a plurality of (three in this case) holes 102b for fastening rivets. The portions in which the holes 102b are formed are the side members 12, 14 (see FIG. 7).
Are fastened with rivets to the flanges 12b and 14b. Further, a concave blank portion 102c is formed at one end of the first flange 102 in the width direction (the direction orthogonal to the arrow B). The first web 104 extends in the direction of arrow B from the other end opposite to the one end, and has a shape that enters the blank portion 102c.
Therefore, the shape of the blank portion 102c and the first web 104
Are identical to each other.

The second member 110 has the same shape as the first member 100, and has both ends 112a in the longitudinal direction (the direction of arrow B).
Are fastened to the side members 12 and 14 (see FIG. 7), the second flange 112 facing the first flange 102, and the second flange 112 integrally formed with the second flange 112.
It has a web 114. A plurality (three in this case) of rivet fastening holes 112b are formed in both end portions 112a. The portion where the hole 112b is formed is the flange 1 of the side members 12, 14 (see FIG. 7).
It is configured to be rivet-fastened to 2b and 14b.

Further, one end of the second web 114 in the width direction is fastened to one end of the first web 104 in the width direction by a rivet 42, whereby the first member 100 and the second member 110 are integrated. It has become. A concave blank portion 112c is formed at one end of the second flange 112 in the width direction (the direction orthogonal to the arrow B). Second web 114
Extends in the direction of arrow B from the other end opposite to the one end, and has a shape that enters the blank portion 112c. Therefore, the blank portion 112c and the second web 114
Are identical and have the same shape.

Here, the first and second webs 104, 11
The strength of the part where the one end of No. 4 is fastened with a rivet will be examined.

Similar to the case of the cross member 40 shown in FIG.
0 corresponds to the center in the width direction of the web. When a force acts on the cross member 90, the central portion in the width direction of the web becomes a neutral shaft (a portion where a lower stress acts on other portions), so that the rigidity and durability of the cross member 90 do not decrease.
The method of manufacturing the cross member 90 is almost the same as the method of manufacturing the cross member 40 shown in FIG. 2. In FIG. 2, the step of bending both ends 82 in the longitudinal direction of the flat plate 80 by about 90 ° at the line 88 is illustrated. If omitted, cross member 9
0 can be produced.

The cross member 90 fixed to the side member will be described with reference to FIGS.

FIG. 4 is a side view schematically showing the cross member 90 fixed to the side member.

The width of the web 122 of the side member 120 to which the cross member 90 is fixed varies depending on the position. The width of the web 122 is the narrowest at the position 122a,
It becomes wider toward the positions 122b and 122c. In order to fasten the cross member 90 to such a web 122, the position where the first and second webs 104 and 114 are fastened is changed according to the width of the web 122. For example, the flange 1 at the position 122c where the width of the web 122 is wide
When the cross member 90 is fastened to the 24, one ends of the first and second webs 104 and 114 in the width direction are fastened to each other as shown in FIG. Thus, the cross member 90 having the wide web width 90a is manufactured, and the cross member 90 can be fastened to the flange 124 at the position 122c where the width of the web 122 of the side member 120 is wide.

On the other hand, the position 122 where the width of the web 122 is narrow
When fastening the cross member to the flange 124 of a,
The central portions of the first and second webs 104 and 114 in the width direction are fastened to each other. Thus, the cross member 92 having a narrow web width 92a can be manufactured, and the cross member 90 can be fastened to the flange 124 at a position 122a where the width of the web 122 of the side member 120 is narrow.

The position 1 where the width of the web 122 is slightly narrower
When the cross member is fastened to the flange 124 of the second web 22b, the widthwise central portion of the first web 104 and the one widthwise end of the second web 114 bent at an angle smaller than 90 ° with respect to the first flange. And conclude. As a result, the cross member 94 having a slightly narrow web width 94a and the first flange and the second flange not parallel to each other is easily manufactured, and the upper and lower portions 122a of the side member 120 where the width of the web 122 is narrow are not parallel. The cross member 94 can be fastened to the flange 124.

As described above, by changing the fastening position and the angle of one of the members, the web widths 90a, 92a, 94a of the cross members 90, 92, 94 can be changed, and cross members having various web widths can be easily formed. At low cost. On the other hand, in the conventional cross members 18 and 28 (see FIGS. 8 and 9), in order to change the web width, the cross members are manufactured using a plurality of types of dies corresponding to the web width. For this reason, the cost of the mold used when manufacturing the cross member increases.

Referring to FIG. 5, a third embodiment of the cross member of the present invention will be described.

FIG. 5 is a perspective view showing a cross member according to the third embodiment.

The cross member 130 has a cross section of “Z” and is called a Z-shaped cross member, and includes a first member 140 and a second member 150 having the same shape. As will be described later, the first and second members 140 and 150 are integrally formed by fastening one ends of the first and second webs 144 and 154 in the width direction with rivets 42. FIG. 5 shows the first and second webs 14.
4,154 are fastened at one end in the width direction, but may be fastened at the center in the width direction or at the center in the width direction and the one end. By changing the fastening position in this way, the width of the web of the cross member 130 can be changed,
Cross members having various web widths can be easily manufactured.

In the first member 140, both end portions 142a in the longitudinal direction (the direction of arrow B) have side members 12, 14 (FIG. 7).
1), and the first web 14 integrally molded with the first flange 142.
Four. Both ends 142a of the first flange 142
Are formed with a plurality (three in this case) of holes 142b for fastening rivets. The portion in which the hole 142b is formed is bent substantially at a right angle, and is configured to be fastened to the webs 12a, 14a of the side members 12, 14 (see FIG. 7) by rivets.

A concave blank portion 14 is provided at one end of the first flange 142 in the width direction (the direction perpendicular to the arrow B).
2c is formed. The first web 144 extends in the direction of arrow B from the other end opposite to the one end,
It is shaped to fit into the blank part 142c. Therefore, the blank portion 142c and the first web 144 have the same shape in conformity with each other.

The second member 150 has the same shape as the first member 140, and has both ends 152a in the longitudinal direction (the direction of arrow B).
Are fastened to the side members 12 and 14 (see FIG. 7), the second flange 152 facing the first flange 142, and the second flange 152 integrally formed with the second flange 152.
It has a web 154. Holes 152b for fastening rivets are formed at both ends 152a of the second flange 152, respectively.
(Here, three each) are formed. This hole 1
The portion where 52b is formed is bent at substantially a right angle,
The webs 12a of the side members 12, 14 (see FIG. 7)
It is configured to be rivet-fastened to 14a.
Further, one end of the second web 154 in the width direction is fastened to one end of the first web 144 in the width direction by the rivet 42, whereby the first member 140 and the second member 150 are integrated. I have. One end of the second flange 152 in the width direction (the direction orthogonal to the arrow B) has a concave blank portion 15.
2c is formed. The second web 154 extends in the direction of arrow B from the other end opposite to the one end,
It is shaped to fit into the blank part 152c. Therefore, the blank portion 152c and the second web 154 have the same shape in conformity with each other.

Here, the first and second webs 144, 15
The strength of the part where one end of 4 is riveted is
As described above, since the fastening portion becomes a neutral shaft, the rigidity and durability of the cross member 130 do not decrease. The method of manufacturing the cross member 130 is almost the same as the method of manufacturing the cross member 40 shown in FIG. 2, but the first and second flanges 142 are opposite to each other with respect to the first and second webs 144 and 154. , 152 are located on the first
And the second members 140 and 150 are arranged, and the first and second members are arranged.
One ends of the webs 144 and 154 are fastened with rivets.

Referring to FIG. 6, a fourth embodiment of the cross member of the present invention will be described.

FIG. 6 is a perspective view showing a cross member according to the fourth embodiment.

The cross member 160 has a Z-shaped cross section and is called a Z-shaped cross member, and includes a first member 170 and a second member 180 having the same shape. The first and second members 170 and 180 are integrally formed by fastening one end of each of the first and second webs 174 and 184 in the width direction with a rivet 42.

In the first member 170, both ends 172a in the longitudinal direction (the direction of arrow B) have side members 12, 14 (FIG. 7).
1), and the first web 17 integrally formed with the first flange 172.
Four. Both ends 172a of the first flange 172
Are formed with a plurality (three in this case) of holes 172b for fastening rivets. The portions where the holes 172b are formed are the side members 12, 14 (see FIG. 7).
Are fastened with rivets to the flanges 12b and 14b. Further, a concave blank portion 172c is formed at one end of the first flange 172 in the width direction (the direction orthogonal to the arrow B). The first web 174 extends in the direction of arrow B from the other end opposite to the one end, and has a shape that enters the blank portion 172c.
Therefore, the blank portion 172c and the first web 174 have the same shape in conformity with each other.

The second member 180 has the same shape as the first member 170, and has both ends 182a in the longitudinal direction (the direction of arrow B).
Are fastened to the side members 12 and 14 (see FIG. 7), the second flange 182 facing the first flange 172, and the second flange integrally formed with the second flange 182.
It has a web 184. Riveting holes 182b are formed at both ends 182a of the second flange 182, respectively.
(Here, three each) are formed. This hole 1
The portion where 82b is formed is configured to be rivet-fastened to flanges 12b and 14b of side members 12 and 14 (see FIG. 7).

Further, one end of the second web 184 in the width direction is fastened to one end of the first web 174 in the width direction by the rivet 42, whereby the first member 170 and the second member 180 are integrated. It has become. A concave blank portion 182c is formed at one end of the second flange 182 in the width direction (the direction orthogonal to the arrow B). Second web 184
Extends in the direction of arrow B from the other end opposite to the one end, and has a shape that enters the blank portion 182c. Therefore, the blank portion 182c and the second web 184
Are identical and have the same shape.

Here, the first and second webs 174, 18
The strength of the part where one end of 4 is riveted is
As high as the case of the cross member 90 shown in FIG.
The rigidity and durability of the cross member 160 do not decrease. The manufacturing method of the cross member 160 is almost the same as the manufacturing method of the cross member 90 shown in FIG.
The first and second members 170 and 180 are arranged so that the first and second flanges 172 and 182 are located on opposite sides of the first and second webs 174 and 184, respectively.
Then, one ends of the second webs 174 and 184 are fastened with rivets.

In each of the above embodiments, the first member and the second
Although the shapes of the members are the same, the blank portion and the web may be formed in the same shape for each member, and the first member and the second member may be used.
The object of the present invention can be achieved without making the blank portions of the members exactly the same shape. For example, in the fourth embodiment shown in FIG. 6, while the width of the web 174 of the first member 170 is reduced to make the blank portion 172c shallower in accordance with this width,
The width of the web 184 of the member 180 may be increased, and the blank portion 182c may be formed deep according to the width.

As described above, according to the cross member of the present invention, since the first web enters the blank portion of the first flange, the first member is prevented from being scraped from one long material. Can be formed. Further, since the second web enters the blank portion of the second flange, the second member can be formed from one piece of the long material so that the scrap does not come out. In addition, since both ends of the flange of each member are fixed to the side members, gussets are not required, and the number of parts can be reduced accordingly. Therefore, a lightweight and low-cost cross member can be obtained.

Here, each of the first and second webs is
When the blank has the same shape as the blank portion, almost no scrap is produced, so that a lower cost cross member can be obtained.

In the case where the first web and the second web are such that the center portions in the width direction or the center portion and the tip portion are fixed instead of the one end portions in the width direction, The width of the web of the cross member can be changed as appropriate.

Further, according to the cross member manufacturing method of the present invention, a plurality of flat plates are formed by cutting a long plate-like material having a width substantially equal to the length of the cross member, and the flat plates are bent to form a cross section. Form an L-shaped partial cross member, and 2
Since the cross member is manufactured by fixing the distal ends of the curved portions of the two partial cross members, the cross member can be manufactured so that the scrap does not come out of one long material. Further, by fixing both ends in the longitudinal direction of the flat plate to the side members, a gusset becomes unnecessary, and the number of parts can be reduced accordingly. Therefore, a lightweight and low-cost cross member can be obtained.

Here, in the fixing step, instead of fixing the tip portions of the curved portions of the two partial cross members, the center portions of the curved portions or the center portion and the tip portion are fixed. Is fixed, the width of the web of the cross member can be appropriately changed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a cross member of the present invention.

FIG. 2 (a) is a plan view showing a long material used as a material of the cross member of the present invention, and FIG. 2 (b) shows a flat plate obtained by cutting the long material shown in FIG. FIG.

FIG. 3 is a perspective view showing a second embodiment of the cross member of the present invention.

FIG. 4 is a side view schematically showing a cross member fixed to a side member.

FIG. 5 is a perspective view showing a third embodiment of the cross member of the present invention.

FIG. 6 is a perspective view showing a fourth embodiment of the cross member of the present invention.

FIG. 7 is a perspective view showing an example of a conventional ladder frame.

FIG. 8 is a perspective view showing a conventional grooved cross member called a gusset type.

FIG. 9 is a perspective view showing a conventional grooved cross member called an integral type.

10A is a schematic diagram showing a punching line when punching a conventional long material, and FIG. 10B is a cross member of a flat plate obtained by punching the long material shown in FIG. FIG.

[Explanation of symbols]

40, 90 Groove-shaped cross member 130, 160 Z-shaped cross member 50, 100, 140, 170 First member 60, 110, 150, 180 Second member 52, 102, 142, 172 First flange 62, 112, 152, 182 Second flange 54, 104, 144, 174 First web 64, 114, 154, 184 Second web 70 Long member 52c, 62c, 102c, 112c, 142c, 15
2c, 172c, 182c Blank part

Claims (5)

[Claims] 1. A cross member having longitudinal ends fixed to two vehicle side members extending parallel to each other at a predetermined distance, wherein the cross member has the both ends and is concave at one end in a width direction. Formed in the first flange, and extending in the longitudinal direction from the other end opposite to the one end in the width direction. The first flange is formed integrally with the first flange and enters the blank portion. A first member having a first web, a second flange having the same shape as the first flange, and having the same shape as the first web, wherein one end in the width direction is one end in the width direction of the first web; A second member having a second web fixed to the portion. 2. The cross member according to claim 1, wherein each of the first and second webs has the same shape as the blank portion. 3. The first web and the second web are such that center portions in the width direction or a center portion and a front end portion are fixed instead of one end portions in the width direction. The cross member according to claim 1 or 2, wherein: 4. A method for manufacturing a cross member in which both longitudinal ends are fixed to two vehicle side members extending parallel to each other at a predetermined distance, wherein the plate has a width substantially equal to the length of the cross member. The long material is formed as a first cutting line extending in the width direction of the long material at both ends in the width direction of the long material, and the first cutting line is formed at the center in the width direction of the long material. By cutting so as to be a continuous bow-shaped or chevron-shaped second cutting line, the long material has a square shape at both ends in the width direction and a curved shape at the center in the width direction of the long material. A cutting step of forming a plurality of flat plates having, by bending a portion of the flat plate having the curved shape with respect to a line extending in a longitudinal direction of the flat plate,
A cross member comprising: a bending step of forming a partial cross member having an L-shaped cross section; and a fixing step of fixing tips of curved portions of the two partial cross members. Production method. 5. The fixing step, instead of fixing the tip portions of the curved portions of the two partial cross members, instead of fixing the tip portions of the curved portions, or between the center portions of the curved portions, or the tip portion. The method for manufacturing a cross member according to claim 4, wherein the cross member is fixed.