WO2022149481A1

WO2022149481A1 - Vehicle chassis frame structure

Info

Publication number: WO2022149481A1
Application number: PCT/JP2021/047911
Authority: WO
Inventors: 康雄秋本; 渉末廣; 謙志荒木; 駿輝門脇; 弘基片村
Original assignee: 三菱自動車工業株式会社
Priority date: 2021-01-08
Filing date: 2021-12-23
Publication date: 2022-07-14
Also published as: JPWO2022149481A1; WO2022149323A1; BR112023013133A2

Abstract

This vehicle chassis frame structure comprises: a pair of right and left side members (11); a bumper frame (17); a first crossmember (13a); and a second crossmember (19) which is disposed below the side members and between the first crossmember and the bumper frame so as to extend in the vehicle width direction; columnar members (31) which extend downward from the respective side members so as to support the right and left ends of the second crossmember; and extension members (33) which extend toward the outer side of the vehicle width direction from the columnar members at the right and left ends of the second crossmember and which extend to the position facing the inner side, in the vehicle front-back direction, of an extension part of the bumper frame.

Description

Chassis frame structure

The present invention relates to the frame structure of the chassis, and particularly relates to a technique for improving collision safety.

A bumper frame extending in the width direction of the vehicle is arranged at the front of the vehicle to absorb the impact at the time of a front collision. In addition, the cushioning portion of the side member that supports the bumper frame absorbs the impact by deforming at the time of a front collision, and can alleviate the impact on the vehicle interior and the like.
Further, in the front collision of the vehicle, there are a plurality of cases such as a so-called full overlap in which the vehicles face each other and collide on the entire surface, and a so-called offset collision in which the vehicles collide with only one of the left and right sides. In particular, in the case of an offset collision, a local load is applied to the left and right ends of the bumper frame, so it is considered that the shock absorbers of the bumper frame and side members are deformed more than expected and cannot sufficiently absorb the impact. ..

Therefore, by arranging side stays that extend from the cross members arranged on the side members and support the left and right ends of the bumper frame, even when a local load is generated on the left and right ends of the bumper frame, A technique for suppressing the deformation of the bumper frame and the cushioning portion of the side member more than expected has been developed (Patent Document 1).

Japanese Patent Application Laid-Open No. 10-203411

However, in the technique disclosed in Patent Document 1, the load at the position corresponding to the side member or the side stay may be locally increased in consideration of the load applied to the other vehicle in the event of an offset collision. , Not preferable.
On the other hand, if the rigidity of the cushioning portion and the side stay of the side member is lowered, the impact absorption performance may be lowered, so that there is room for further improvement.

The present invention has been made in view of such a problem, and an object of the present invention is to maintain the impact absorption performance at the time of a vehicle collision and to apply a local load to the other vehicle (collision object). The purpose is to provide an chassis frame structure that can reduce the occurrence.

In order to achieve the above object, the frame structure of the chassis of the present invention is a frame structure of the chassis that supports the body of the vehicle, and has a pair of left and right side members extending in the front-rear direction of the vehicle and the front-rear direction of the side members. It is provided between the bumper frame having an extension portion extending in the vehicle width direction from the side member and extending outward in the vehicle width direction at the outer end portion, and the pair of left and right side members, and extending in the vehicle width direction. A second cross member located below the side member and between the first cross member and the bumper frame and extending in the vehicle width direction, and a second cross member extending downward from the side member and described above. The pillar member that supports the left and right ends of the second cross member and the pillar member at the left and right ends of the second cross member extend outward in the vehicle width direction, and the extension portion of the bumper frame extends in the vehicle front-rear direction. It is characterized by including an extension member extending to a position facing each other on the inside.

As a result, the second cross member extending in the vehicle width direction is positioned below the side member between the first cross member and the bumper frame, and the second cross is provided by the pillar member extending downward from the cushioning portion of the side member. Supporting the left and right ends of the member, extending members extending outward in the vehicle width direction and located inside the vehicle front-rear direction outside the side member of the bumper frame in the vehicle width direction are arranged at the left and right ends of the second cross member. By supporting the left and right ends of the second cross member with the pillar member, the second cross member is swung outward from the vehicle around the upper end of the pillar member and pressed to bring it into contact with the collided object at an early stage. Is possible.

As another aspect, it is preferable to have a cushioning portion between the bumper frame of the side member and the first cross member, which buckles and absorbs an impact when a load of a predetermined value or more is applied in the front-rear direction of the vehicle.
As a result, a cushioning portion is provided between the bumper frame of the side member and the first cross member to absorb the impact by buckling when a load exceeding a predetermined value is applied in the front-rear direction of the vehicle, for example, as in a full overlap collision. When the entire bumper frame receives an impact, the extension member and the second cross member do not prevent the shock absorber from collapsing, and when the impact is biased to one side in the vehicle width direction of the bumper frame such as an offset collision. It is possible to reduce the local increase in rigidity at the position corresponding to the cushioning portion by allowing the extension member or the second cross member to support the bumper frame.

As another embodiment, the side member is provided with a mount bracket provided at a position where the pillar member is provided and supports the body, and the mount bracket is provided with a mount support portion to which the mount member connected to the body is attached. It has a front wall portion and a rear wall portion that extend downward from the front and rear of the mount support portion at intervals from each other and are joined to the outer side surface in the vehicle width direction of the side member, and the pillar member is the mount. It is preferable that the bracket is joined to the side surface of the side member between the front wall portion and the rear wall portion.

As a result, a mount bracket for supporting the body is provided at a place where the pillar member of the side member is provided, and extends downward from between the front wall portion and the rear wall portion joined to the outer side surface of the side member in the vehicle width direction. By providing the column member, it is possible to increase the strength of the portion of the side member to which the column member is attached.
As another aspect, the extension member has an inner protrusion that protrudes toward the center from the inner end of the second cross member in the vehicle front-rear direction, and the inner protrusion is the left and right side members. When any one of the portions between the bumper frame and the first cross member is crushed, it is preferably provided at a position where it comes into contact with the first cross member.

As a result, the inner protruding portion protruding toward the center from the inner inner end portion of the second cross member in the vehicle front-rear direction is one of the locations between the bumper frame and the first cross member of the left and right side members. By contacting the first cross member when one of them is crushed, the inner protruding portion contacts the first cross member at the time of offset collision, and the inside of the second cross member in the vehicle width direction is in the vehicle front-rear direction with the inner protruding portion as an axis. It is possible to swing to the center side and press the extension member located outside the vehicle width direction from the inner protrusion to the outside in the vehicle front-rear direction, that is, to the other vehicle side.

As another aspect, the extension member has a fixing portion in which one end is fixed to the outer end portion of the extension member in the vehicle width direction and the other end is fixed to the extension portion of the bumper frame. preferable.
As a result, by providing a fixed portion extending from the outer end portion of the extension member in the vehicle width direction to the outer end portion in the vehicle width direction from the side member of the bumper frame, the bumper frame moves in the vehicle front-rear direction in the event of a vehicle collision. It is possible to suppress rocking.

As another aspect, the extension member has a first member having an opening open to the center side in the front-rear direction of the vehicle, and a second member having a second member closing at least a part of the opening of the first member. preferable.
This makes it possible to secure the rigidity of the extension member.

As another aspect, it is preferable that the second cross member is formed with a rigidity reducing portion in the center in the vehicle width direction, which reduces the rigidity against a force of bending in the vehicle front-rear direction.
As a result, a rigidity lowering portion that reduces the rigidity against the force of bending in the vehicle front-rear direction is formed at the center of the second cross member in the vehicle width direction, so that the rigidity reduction portion of the second cross member is centered in the vehicle front-rear direction at the time of a collision. The bumper frame can be pressed outward by the reinforcing portion by utilizing the force pressed to the side.

As another embodiment, the extension member is connected to the pillar member and has a connection portion extending in the vehicle front-rear direction and a left-right extension portion extending outward in the vehicle width direction from an end portion of the connection portion on the outside in the vehicle front-rear direction. The left and right extension portions have the fixing portion fixed by a fixing member extending in the vertical direction of the vehicle at the outer end portion in the vehicle width direction.
As a result, in the event of a full overlap collision, the fixing portion rotates around the fixing member extending in the vertical direction of the vehicle, so that the impact is absorbed while reducing the increase in the rigidity of the cushioning portion due to the extending member and the fixing portion. be able to.

According to the frame structure of the chassis of the present invention, a second cross member extending in the vehicle width direction is positioned below the side member and between the first cross member and the bumper frame, and the second cross member extends from the cushioning portion of the side member. The left and right ends of the second cross member are supported by the pillar members extending downward, extending outward in the vehicle width direction to the left and right ends of the second cross member, and inside the vehicle front-rear direction outside the side member of the bumper frame in the vehicle width direction. Since the extension member located at is arranged and the left and right ends of the second cross member are supported by the pillar member, the second cross member is swung outward and pressed with the upper end of the pillar member as an axis. It can be brought into contact with the collided object at an early stage. As a result, it is possible to reduce the generation of a local load applied to the collided body while maintaining the impact absorption performance at the time of a vehicle collision.

It is a rear perspective view of the front part of the chassis of a vehicle. It is a side view of the front part of the chassis. It is a lower view of the front part of the chassis. It is an enlarged view of the range A in FIG. It is a top view of the extension member. It is explanatory drawing explaining the deformation of the front part of the chassis when another vehicle collides from the front of the vehicle with full overlap. It is explanatory drawing explaining the deformation of the front part of the chassis when another vehicle makes an offset collision from the front of a vehicle. It is explanatory drawing explaining the deformation of the front part of the chassis when another vehicle makes an offset collision from the front of a vehicle. It is explanatory drawing explaining the deformation of the front part of the chassis when another vehicle makes an offset collision from the front of a vehicle. It is the upper view of the front part of the chassis in the modification. It is a perspective view which shows the periphery of the extension member in the modification. It is a perspective view of the extension member in the modification.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
Referring to FIG. 1, a rear perspective view of the front portion of the chassis 3 of the vehicle 1 is shown. The vehicle 1 is an automobile having a chassis 3 having a frame structure. That is, the vehicle 1 is configured by mounting a body including the cabin 2, an upper body (not shown), an engine, and the like on the chassis 3.

The chassis 3 is the skeleton of the vehicle 1 formed by combining a plurality of frame members. Specifically, the chassis 3 includes a side member 11, a suspension frame 13, a mount bracket 15, a bumper frame 17, and a lower cross member (second cross member) 19.

The side members 11 are, for example, iron prism members that are arranged in pairs on the left and right and extend in the front-rear direction of the vehicle. The side member 11 is located below the center of the vehicle 1 in the vertical direction. Further, the pair of left and right side members 11 are fixed to each other by a plurality of cross member members extending in the vehicle width direction such as the suspension frame 13 and the lower cross member 19, and relative swinging is suppressed.

The suspension frame 13 is a frame provided between a pair of left and right side members 11 and including a front cross member member (first cross member) 13a extending in the vehicle width direction and a rear cross member member 13b. By providing a lower arm (not shown), the suspension frame 13 can alleviate vibrations and impacts transmitted from the ground to the vehicle 1 while supporting the drive shaft.

With reference to FIG. 2, a side view of the front part of the chassis 3 is shown. Further, referring to FIG. 3, a lower view of the front portion of the chassis 3 is shown. An extension (buffer) 12 is formed on the front portion of the side member 11. The extension 12 is formed in a range from the front end (end) 11a of the side member 11 to the front end of the front cross member member 13a of the suspension frame 13, and buckles when a predetermined load or more is applied in the front-rear direction of the vehicle. It is formed to absorb impact.

With reference to FIG. 4, an enlarged view of the range A in FIG. 1 is shown. The mount bracket 15 is a frame on which the cabin (body) 2 of the vehicle 1 is mounted via the mount member 16. Further, the mount bracket 15 is arranged on the outer side of the pair of left and right side members 11 in the vehicle width direction from the front end 11a of the side members 11 to the front end of the front cross member member 13a, that is, on the extension 12.

The mount bracket 15 has a mount support portion 15a to which a mount member 16 connected to the cabin 2 is attached by bending a flat plate member, and a lower portion of the mount support portion 15a at a distance from the front end portion and the rear end portion. A front wall portion 15b and a rear wall portion 15c, which extend to the side member 11 and are joined to the outer side surface in the vehicle width direction of the side member 11, are formed. As a result, the mount bracket 15 is formed in a box shape that opens outward and downward in the vehicle width direction.

The bumper frame 17 has a lower cushioning member 21, an upper cushioning member 23, and a fixing bracket 25, and is located at the front end of the chassis 3. The front side of the bumper frame 17 is covered with a resin bumper (not shown) provided at the front end of the vehicle 1.
The lower cushioning member 21 is a cushioning member that extends in the vehicle width direction and is fixed to the front end 11a of the side member 11 by, for example, a bolt. The lower cushioning member 21 is bent so that an end portion (extension portion) 21a extending outward in the vehicle width direction from a position fixed to the front end 11a of the side member 11 is inclined toward the rear. The upper cushioning member 23 is a cushioning member that extends in the vehicle width direction and is located above the lower cushioning member 21. The upper cushioning member 23 is bent so that the end portion on the outer side in the vehicle width direction is inclined toward the rear. Further, the upper cushioning member 23 is fixed to the lower cushioning member 21 by a plurality of fixing brackets 35 extending in the vertical direction of the vehicle.

Therefore, when a load is applied from the front to the rear of the vehicle, for example, in a front collision accident of the vehicle 1, the bumper frame 17 receives the load applied to the front of the side member 11 and from above and behind the side member 11 as a whole. Can be done.
The lower cross member 19 is a frame member that is located below the side member 11 and is located between the suspension frame 13 and the bumper frame 17 and extends in the vehicle width direction. By providing the lower cross member 19, the chassis 3 suppresses the relative swing of the pair of left and right side members 11 and the chassis rigidity, similarly to the plurality of cross member members (not shown) provided on the side member 11. Can be enhanced. The lower cross member 19 is provided with a deformation hole (rigidity lowering portion) 19a extending in the vertical direction at the center in the vehicle width direction. Further, a pillar member 31 and an extension member 33 are provided at the left and right ends of the lower cross member 19, and are fixed to the side member 11 by the pillar member 31.

The pillar member 31 is a skeleton member extending downward from the inside in the front-rear direction of the position vehicle between the front wall portion 15b and the rear wall portion 15c of the mount bracket 15 on the left and right side members 11. The lower end of the pillar member 31 is welded to the left and right ends of the lower cross member 19, for example. Therefore, the lower cross member 19 is supported below the mount bracket 15 so as to be suspended at both the left and right ends by the pillar member 31.

Thereby, the mount bracket 15 can firmly support the pillar member 31, and the mount bracket 15 can also be increased in rigidity by providing the pillar member 31 on the mount bracket 15. Further, since the mount bracket 15 is arranged on the extension 12, it is possible to appropriately allow the extension member 33 to move due to the deformation of the extension 12.

With reference to FIG. 5, an upper view of the extension member 33 is shown. According to FIGS. 4 and 5, the extension member 33 is a pair of left and right members that are joined to the left and right ends of the lower cross member 19 via the lower end of the pillar member 31 and extend outward in the left-right direction. Further, the extension member 33 is formed in an arc shape when viewed from the vertical direction of the vehicle, and the rear side (one end) in the vehicle front-rear direction extends in the vehicle front-rear direction to the outer end portion of the lower cross member 19 in the vehicle width direction. It is welded and the front side (the other end) extends in the vehicle width direction.

Specifically, the extending member 33 is formed with a connecting portion 33a, a left and right extending portion 33b, a rear protruding portion (inner protruding portion) 33c, and a fixing portion 33d. The connecting portion 33a is formed so as to extend in the front-rear direction of the vehicle, and is connected to the outer surface of the pillar member 31 connected to the left and right ends of the lower cross member 19. The left-right extending portion 33b extends in an arc shape from the end portion of the connecting portion 33a on the front side in the vehicle front-rear direction toward the outside in the vehicle width direction. The rear protruding portion 33c extends rearward from the rear end portion of the connecting portion 33a in the vehicle front-rear direction and extends inward in the vehicle width direction to project rearward from the rear end 19b of the lower cross member 19, and the vehicle width of the suspension frame 13. It is formed so as to be located outward from the end on the outer side in the direction.

The fixed portion 33d is a member formed by bending a flat plate member. The fixed portion 33d is welded to the upper surface of the left end (outer end in the vehicle width direction) of the left and right extending portions 33b of the extending member 33, and extends toward the rear side surface of the end portion 21a of the lower cushioning member 21. Therefore, when the load in the vehicle front-rear direction is applied to the end portion 21a of the lower cushioning member 21, the fixed portion 33d transmits the load to the left end (outer end in the vehicle width direction) of the left and right extension portions 33b of the extension member 33. Can be made to. Further, in the fixed portion 33d, when a load in the front-rear direction of the vehicle is applied from the lower cross member 19 to the extending member 33 as in the case of an offset collision described later, the load is applied to the left end (vehicle) of the lower cushioning member 21. It can be transmitted to the outer end in the width direction).

The extension member 33 includes a first member 41 (outer member) having an opening that opens rearward (center side in the front-rear direction of the vehicle) and a second member 43 (the second member 43) that closes at least a part of the opening of the first member 41. Inner member) and. Since the second member 43 of the present embodiment is arranged inside the first member 41, the first member 41 is also referred to as an outer member 41, and the second member 43 is also referred to as an inner member 43 for convenience. The outer member 41 is a member formed in an arc shape by bending a flat plate member so as to extend forward and to the left (outside in the vehicle width direction) from the outer end portion of the lower cross member 19 in the vehicle width direction. Further, the outer member 41 has a rear end on the lower cross member 19 side extending rearward from the rear end surface of the lower cross member 19 to form a part of the rear protruding portion 33c. The outer member 41 has an upper end surface and a lower end surface formed by bending the upper end and the lower end to the rear and left, in other words, an opening that opens to the rear and left (outside in the vehicle width direction) is formed. Being done.

The inner member 43 is formed by bending a flat plate member in an arc shape along the outer member 41. The inner member 43 extends from the end portion 41a of the upper end surface of the outer member 41 toward the end portion 41b of the lower end surface. Further, the inner member 43 is formed with a protruding portion 43a extending downward from the end portion 41b of the lower end surface of the outer member 41. The inner member 43 is located inside the outer member 41 and has a shape that opens forward (outward in the front-rear direction of the vehicle). As a result, the inner member 43 closes at least a part of the opening of the outer member 41.

Thereby, the extension member 33 can transmit the load to the lower cross member 19 without being deformed even when the load in the vehicle front-rear direction is applied to the left end portion (the outer end portion in the vehicle width direction). On the other hand, since the extension member 33 is thinner and has lower rigidity than the lower cross member 19, when another vehicle 100 collides from the front of the vehicle 1 described later, the extension member 33 is compared with the lower cross member 19. It deforms greatly.

Next, the deformation and action effect of the front part of the chassis 3 when another vehicle (collision body) 100 collides from the front of the vehicle 1 will be described. Hereinafter, the case where another vehicle 100 collides with the entire left-right direction of the bumper frame 17 as shown in FIG. 6 is referred to as a “full overlap collision”, and is referred to as a “full overlap collision” from the center of the bumper frame 17 in the left-right direction as shown in FIGS. The case where another vehicle 100 collides with the left side is called "offset collision".

With reference to FIG. 6, an explanatory diagram explaining the deformation of the front part of the chassis 3 when another vehicle 100 collides with the other vehicle 100 from the front of the vehicle 1 is shown. When another vehicle 100 collides in front of the vehicle 1 with full overlap and a load is uniformly applied in the vehicle width direction of the bumper frame 17, the shock absorber C is crushed so as to contract in the vehicle front-rear direction. Here, the shock absorber C corresponds to a portion of the chassis 3 from the front end 11a of the side member 11 to the front cross member member 13a of the suspension frame 13. That is, the cushioning portion C includes the extension 12.

When another vehicle 100 collides with the front part of the bumper frame 17 and a predetermined load is applied to the left and right extensions 12, the left and right extensions 12 collapse toward the rear. At this time, since the rear protruding portion 33c of the extending member 33 is located outside the left and right outer ends of the front cross member member 13a, the rear contracting portion 12a is crushed and the lower cross member 19 and the front cross member member 13a are collapsed. Even if they are close to each other, they do not come into contact with the front cross member member 13a. Therefore, when the other vehicle 100 collides with the vehicle 1 in full overlap, the rear protrusion 33c of the extension member 33 does not come into contact with the front cross member member 13a, so that the collapse margin of the rear contraction portion 12a is maintained. can do.

Further, in a full overlap collision, the vehicle 1 collides with the other vehicle 100 on the entire surface in the vehicle width direction by the bumper frame 17, so that the rigidity on the vehicle 1 side is suppressed from being locally increased, and eventually the other vehicle 100. It is possible to suppress the application of a high load locally.
In particular, since the lower cross member 19 is supported by the pillar member 31, it can swing so as to move backward with the upper end of the pillar member 31 as an axis, and thus is buffered by the extending member 33 and the fixing portion 33d. It is possible to absorb the impact while reducing the increase in the rigidity of the portion C.

Further, since the fixing portion 33d is not directly attached to the lower cross member 19, but is attached to the extension member 33 having a lower rigidity than the lower cross member 19, the extension member 33 and the extension member 33 when the front cross member member 13a is crushed. It is possible to absorb the impact while satisfactorily reducing the increase in the rigidity of the cushioning portion C by the fixing portion 33d.
With reference to FIGS. 7 to 9, explanatory views illustrating deformation of the front portion of the chassis 3 when another vehicle 100 offset-collides from the front of the vehicle 1 are shown. When another vehicle 100 collides offset from the front of the vehicle 1 and a load is applied to the left side of the bumper frame 17 from the center in the vehicle width direction to the rear, the left side of the shock absorber C from the center in the left-right direction is shown in FIGS. 7 to 9. As shown in order, it collapses in the front-rear direction of the vehicle.

Specifically, first, the posterior contracted portion 12a is crushed (see FIG. 7). As a result, not only the impact can be absorbed by the extension 12, but also the impact can be absorbed by absorbing the impact when bending the lower cross member 19.
Further, when another vehicle 100 collides with an offset from the front of the vehicle 1, the lower cross member 19 is curved in the vicinity of the deformation hole 19a, so that the lower cross member 19 is not provided with, for example, the deformation hole 19a. It is possible to contact the other vehicle 100 earlier than when the member is used. Further, since the lower cross member 19 is formed with the deformed hole 19a, the lower cross member 19 can be curved in the vicinity of the deformed hole 19a, so that the extending member 33 swings around the deformed hole 19a and protrudes rearward. The portion 33c can be brought into contact with the left end front side of the front cross member member 13a. In particular, since the extension member 33 swings toward the rear side of the vehicle with the upper end of the pillar member 31 as the axis, the rear protrusion 33c can be brought into contact with the other vehicle 100 at an early stage.

After that, when the other vehicle 100 advances toward the vehicle 1, the lower cross member 19 curves at the deformation hole 19a (see FIGS. 8 and 9). In the lower cross member 19 curved in the deformed hole 19a in this way, the portion in the vicinity of the deformed hole 19a is pressed backward by the other vehicle 100. At this time, a force in the rotational direction is generated on the extending member 33 to push the left end forward with the pillar member 31 as the axis.
As a result, the lower cross member 19 on the left side directs the left and right extension portions 33b of the extension member 33 toward the front of the vehicle as the portion near the deformation hole 19a is pressed backward by the other vehicle 100. The left side of the bumper frame 17 can be pressed against the other vehicle 100 via the fixing portion 33d. In particular, when the extending member 33 is pressed backward via the fixing portion 33d, the lower cross member 19 faces the vehicle front side (outside the vehicle) in the vicinity of the deformation hole 19a with the pillar member 31 as an axis in the vertical direction. The lower cross member 19 can be brought into contact with the other vehicle 100 at an early stage. Therefore, by bringing the lower cross member 19 into contact with the other vehicle 100 at an early stage, the left side of the bumper frame 17 can be pressed against the other vehicle 100 at an early stage via the fixing portion 33d.

Therefore, even if the extension 12 on the right side is not crushed due to the offset collision, the impact absorption is insufficient with the extension 12 on the left side alone, and the cushioning property is lower than that of the full overlap collision, the lower cross The member 19 is deformed so as to be curved, and the extension member 33 presses the left side of the bumper frame 17 against the other vehicle 100 via the fixing portion 33d to increase the rigidity of the left side of the cushioning portion C to make it full. It is possible to secure the same cushioning property as the overlap collision (see FIG. 9).

Further, as described above, the bumper frame 17 is formed by fixing the upper cushioning member 23 to the upper side of the lower cushioning member 21 attached to the front end 11a of the side member 11 with the fixing bracket 25. Here, considering the case where the fixing portion 33d is not provided, the upper end of the bumper frame 17 is the side member 11 when the upper cushioning member 23 is positively pressed backward in the front-rear direction of the vehicle. It swings so as to tilt backward with the front end 11a of the above as an axis.

Therefore, by providing the fixing portion 33d and pulling the lower end of the lower cushioning member 21 downward and rearward, the extension 12 accurately exerts an impact while suppressing the bumper frame 17 from swinging as described above. Can be absorbed.

Next, a modification of the present invention will be described with reference to FIGS. 10 to 12. FIG. 10 is an upper view of the front portion of the chassis 3 in the modified example. FIG. 11 is a perspective view showing the periphery of the extension member 33 in the modified example. FIG. 12 is a perspective view of the extension member 33 in the modified example. In FIG. 12, the fixed portion 33d of the extending member 33 is not shown.

The shape of the extension member 33 of this modification is different from that of the above-described embodiment. More specifically, the left and right extension portions 33b of the extension member 33 of the above-described embodiment are formed in an arc shape when viewed from the vertical direction of the vehicle (see FIG. 5), but the extension member of this modification The left and right extending portions 33b of 33 are formed in a substantially straight line when viewed from the vertical direction of the vehicle.

The extension member 33 of this modification includes a connection portion 33a, a left and right extension portion 33b, a rear protrusion (inner protrusion) 33c, and a fixing portion 33d, as in the above-described embodiment.

The connecting portion 33a is formed so as to extend in the front-rear direction of the vehicle, and is connected to the outer surface of the pillar member 31 connected to the left and right ends of the lower cross member 19. The left and right extending portions 33b extend substantially linearly from the front end portion of the connecting portion 33a in the vehicle front-rear direction toward the outside in the vehicle width direction. The rear protruding portion 33c extends rearward from the rear end portion of the connecting portion 33a in the vehicle front-rear direction and extends inward in the vehicle width direction to project rearward from the rear end 19b of the lower cross member 19.

The rear end portion of the fixing portion 33d is fixed to the upper surface of the left end (outer end in the vehicle width direction) of the left and right extending portions 33b by a bolt 40 as a fixing member, and the end portion 21a of the lower cushioning member 21 of the bumper frame 17 ( It extends toward the rear side surface (see FIG. 1). Through holes (not shown) for fixing the bolts 40 are formed in the fixing portion 33d and the left and right extending portions 33b in the vertical direction of the vehicle. Therefore, the bolt 40 screwed and fixed to the through hole is arranged so as to extend in the vertical direction of the vehicle.

The front end of the fixing portion 33d is fixed to the rear side surface of the end portion 21a (see FIG. 1) of the lower cushioning member 21 of the bumper frame 17 by a bolt 42 extending in the front-rear direction of the vehicle. The fixed portion 33d is arranged so as to be inclined so as to extend outward in the vehicle width direction toward the front. That is, the line connecting the rear end portion of the fixed portion 33d and the left and right extension portions 33b by the bolt 40 and the front end portion of the fixed portion 33d and the connecting portion of the bumper frame 17 by the bolt 42 is the front. It extends outward in the width direction toward.

The extension member 33 has a first member 41 having an opening that opens rearward (center side in the front-rear direction of the vehicle), and a second member 43 that closes at least a part of the opening of the first member 41. The first member 41 is a member having a substantially L-shape when viewed from the vertical direction of the vehicle, extending forward and to the left (outside in the vehicle width direction) from the outer end portion of the lower cross member 19 in the vehicle width direction. Further, the outer member 41 has a rear end on the lower cross member 19 side extending rearward from the rear end surface of the lower cross member 19 to form a part of the rear protruding portion 33c. The outer member 41 has an upper end surface and a lower end surface formed by bending the upper end and the lower end to the rear and left, in other words, an opening 41c that opens to the rear and left (outside in the vehicle width direction). It is formed.

The inner member 43 is formed by bending a flat plate member along the outer member 41. That is, the inner member 43 includes a first portion 43c extending in the front-rear direction to form a connecting portion 33a, and a second portion 43d extending outward from the front end of the first portion 43c in the vehicle width direction to form a left-right extending portion 33b. It has a third portion 43e extending inward in the vehicle width direction from the rear end of the first portion 43c to form a rear protrusion 33c.

The inner member 43 extends from the end portion 41a of the upper end surface of the outer member 41 toward the end portion 41b of the lower end surface. Further, the inner member 43 is formed with a protruding portion 43a extending downward from the end portion 41b of the lower end surface of the outer member 41 and another protruding portion 43b extending upward from the end portion 41a of the upper end surface of the outer member 41. It becomes. As a result, the inner member 43 closes at least a part of the opening 41c of the outer member 41.

In this modification, the fixing portion 33d and the left and right extending portions 33b are fixed by bolts 40 as fixing members extending in the vertical direction of the vehicle, and therefore, as will be described later, a full overlap collision (see FIG. 6). It is possible to improve the shock absorbing effect when the above occurs.

As described above with reference to FIG. 6, when another vehicle 100 collides with the front of the vehicle 1 in full overlap and a predetermined load is applied to the left and right extensions 12, as shown in FIG. 10, the front end portion of the fixed portion 33d A load Fa is applied to the connection portion between the bumper frame 17 and the bumper frame 17 by the bolt 42 toward the rear. Here, the connection portion between the rear end portion of the fixing portion 33d and the left and right extension portions 33b by the bolt 40 is located inside in the vehicle width direction with respect to the connection portion between the front end portion of the fixing portion 33d and the bumper frame 17 by the bolt 42. Therefore, a moment load Fb that tries to rotate the fixed portion 33d with the bolt 40 as the central axis is generated. When this moment load Fb exceeds the fastening force between the fixing portion 33d by the bolt 40 and the left and right extension portions 33b, the fixing portion 33d rotates in the direction of the moment load Fb. Therefore, it is possible to absorb the impact while reducing the increase in the rigidity of the cushioning portion C by the extending member 33 and the fixing portion 33d. The fixing member for fixing the left and right extending portions 33b and the fixing portion 33d is not limited to the bolt 40, and for example, a pin or the like may be adopted.

As described above, the chassis frame structure according to the present invention is a chassis frame structure that supports the cabin 2 that is a part of the body of the vehicle 1, and has a pair of left and right side members 11 extending in the front-rear direction of the vehicle. , A bumper frame 17 having an end portion 21a extending in the vehicle width direction from the side member 11 outside the vehicle front-rear direction, that is, the front end 11a on the front side of the side member 11 and extending outward from the side member 11 in the vehicle width direction. , A front cross member member 13a of the suspension frame 13, which is provided between the side members 11 and extends in the vehicle width direction.

Further, in the end structure of the vehicle 1 according to the present invention, the lower cross member 19 which is located below the side member 11 and is located between the front cross member member 13a and the bumper frame 17 and extends in the vehicle width direction. A pillar member 31 that extends downward from the side member 11 and supports the left and right ends of the lower cross member 19, and is arranged at the left and right ends of the lower cross member 19 via the pillar member 31 and faces outward in the vehicle width direction. The extension member 33 extends to a position facing the end portion 21a of the bumper frame 17 in the vehicle front-rear direction.

Therefore, the lower cross member 19 extending in the vehicle width direction is positioned below the side member 11 between the front cross member member 13a and the bumper frame 17, and the pillar member extending downward from the extension 12 of the side member 11. 31 supports the left and right ends of the lower cross member 19, extends outward in the vehicle width direction to the left and right ends of the lower cross member 19, and is on the rear side in the vehicle front-rear direction outside the side member 11 of the bumper frame 17. The extension member 33 to be located is arranged so that the extension member 33 supports the bumper frame 17, and the lower cross member 19 is located below the side member 11, so that it is attached to the side member 11. It is possible to promote the swing of the lower cross member 19 and the extension member 33 at the time of a collision, as compared with the case where the lower cross member 19 and the extension member 33 are oscillated. That is, since the left and right ends of the lower cross member 19 are supported by the pillar member 31, the lower cross member 19 is swung toward the front side of the vehicle and pressed with the upper end of the pillar member 31 as an axis to contact the other vehicle 100 at an early stage. Can be made to.

Then, between the bumper frame 17 of the side member 11 and the front cross member member 13a of the suspension frame 13, an extension 12 that buckles and absorbs an impact when a predetermined load or more is applied in the front-rear direction of the vehicle is provided. Therefore, when the entire bumper frame 17 is impacted, for example, in a full overlap collision, the bumper frame 17 is supported so that the load is evenly applied to the left and right extensions 12, and the extensions 12 are crushed equally on the left and right. In the case of an impact that is biased in the vehicle width direction of the bumper frame 17 such as an offset collision, the extension member 33 supports the bumper frame 17 so as to support the bumper frame 17 locally at a position corresponding to the extension 12. It is possible to reduce the increase in rigidity.

Further, an extension 12 of the side member 11 in the front-rear direction of the vehicle, that is, a mount bracket 15 provided at a position where the mount bracket 15 is provided and supporting the cabin 2 which is a part of the body of the vehicle 1, is provided, and the mount bracket 15 is provided. Before the mount support portion 15a to which the mount member 16 connected to the cabin 2 is attached and the mount support portion 15a extend downward from the front and rear at a distance from each other and are joined to the outer side surface of the side member 11 in the vehicle width direction. Since the extension member 33 has a wall portion 15b and a rear wall portion 15c so as to extend from the side member 11 between the front wall portion 15b and the rear wall portion 15c, the pillar member 31 in the side member 11 is formed. The strength of the part to be attached can be increased.

The extension member 33 has a rear protrusion 33c that protrudes toward the center from the rear end (inner end) 19b of the lower cross member 19, and the rear protrusion 33c is the bumper frame 17 and the front side of the side member 11. It is provided at a position where it comes into contact with the front cross member member 13a when any one of the portions between the cross member member 13a and the cross member member 13a is crushed. As a result, the rear protruding portion 33c comes into contact with the front cross member member 13a at the time of an offset collision, and the inside of the lower cross member 19 in the vehicle width direction is swung toward the center side in the vehicle front-rear direction with the rear protruding portion 33c as an axis. The extension member 33 located outside the vehicle width direction from the portion 33c can be pressed outward in the vehicle front-rear direction, that is, toward the other vehicle side.

In particular, since the rear protruding portion 33c is located outward from the outer end portion of the front cross member member 13a in the vehicle width direction, the rear protruding portion 33c is in contact with the front cross member member 13a at the time of an offset collision. It is possible to prevent the rear protrusion 33c from coming into contact with the front cross member member 13a during a full overlap collision.

Since one end has a fixed portion 33d fixed to the outer end portion of the extension member 33 in the vehicle width direction and the other end fixed to the end portion 21a of the bumper frame 17, the bumper frame 17 has a fixed portion 33d when the vehicle 1 collides. Can be suppressed from swinging in the front-rear direction of the vehicle.

Further, since the lower cross member 19 is formed with a deformation hole 19a in the center in the vehicle width direction to reduce the rigidity against the force of bending in the vehicle front-rear direction, the deformation hole 19a of the lower cross member 19 is formed in the vehicle front-rear direction at the time of a collision. The bumper frame 17 can be pressed outward by the reinforcing portion by utilizing the force pressed toward the center side.

The left and right extension portions 33b of the extension member 33 include a first member 41 having an opening that opens toward the center in the front-rear direction of the vehicle, and a second member 43 that closes at least a part of the opening of the first member 41. Therefore, the rigidity of the extension member 33 can be ensured.

The extension member 33 in the modified example is connected to the pillar member 31, and has a connection portion 33a extending in the vehicle front-rear direction and a left-right extension portion extending outward in the vehicle width direction from the end portion of the connection portion 33a outside the vehicle front-rear direction. It has a 33b and a fixing portion 33d fixed by a bolt 40 as a fixing member at an end portion of the left and right extending portions 33b on the outer side in the vehicle width direction. Therefore, at the time of a full overlap collision, the fixing portion 33d rotates around the fastening portion by the bolt 40, so that the impact is absorbed while reducing the increase in the rigidity of the cushioning portion C by the extending member 33 and the fixing portion 33d. can do.

The description of the frame structure of the chassis according to the present invention is completed above, but the present invention is not limited to the above embodiment and can be changed without departing from the gist of the present invention.

For example, in the present embodiment, the extension 12, the bumper frame 17, the lower cross member 19, and the like are arranged in the front part of the vehicle 1, and the case where the other vehicle 100 collides from the front of the vehicle 1 has been described. The rear portion of 1 may be configured in the same manner to prepare for a case where another vehicle 100 collides from behind the vehicle 1.

Further, in the present embodiment, the rear protruding portion 33c is formed on the extending member 33, but it may be formed on the lower cross member 19, and the rear cross member member 13a of the suspension frame 13 may be formed on the rear protruding portion 33c. A portion protruding forward may be formed at a corresponding position.

Further, in the present embodiment, the fixed portion 33d is used, but the lower end of the lower cushioning member 21 of the bumper frame 17 is extended, and the extended member 33 is used as a bumper when the vehicle 1 collides with another vehicle 100. It may be in direct contact with the frame 17.

This application is based on the Japanese patent application 2021-002080 filed on January 8, 2021 and the PCT international application PCT / JP2021 / 037404 filed on October 8, 2021, the contents of which are incorporated herein by reference. ..

1 vehicle 2 cabin (body)
3 Chassis 11 Side member 11a Front end (end)
12 Extension (buffer)
13a Front cross member member (first cross member)
15 Mount bracket

15a Mount support

15b Front wall

15c Rear wall 16 Mount member 17 Bumper frame 19 Lower cross member (second cross member)
19a Deformation hole (stiffness reduction part)
19b Rear end (inner end)
21a End (extension)
31 Pillar member 33 Extension member 33a Connection part 33b Left and right extension part 33c Rear protrusion (inner protrusion)
33d fixing part 40 bolt (fixing member)
41 Outer member (first member)
43 Inner member (second member)
100 Other vehicle (collision object)

Claims

The frame structure of the chassis that supports the body of the vehicle,
A pair of left and right side members extending in the front-rear direction of the vehicle,
A bumper frame extending in the vehicle width direction at the outer end of the side member in the vehicle front-rear direction and having an extension portion extending outward in the vehicle width direction from the side member.
A first cross member provided between the pair of left and right side members and extending in the vehicle width direction,
A second cross member located below the side member and between the first cross member and the bumper frame and extending in the vehicle width direction.
A pillar member extending downward from the side member and supporting the left and right ends of the second cross member.
An extension member extending outward from the pillar member at the left and right ends of the second cross member toward the outside in the vehicle width direction and extending to a position facing the inside of the extension portion of the bumper frame in the vehicle front-rear direction. Chassis frame structure with.
The first aspect of the present invention is characterized in that, between the bumper frame of the side member and the first cross member, there is a shock absorber that buckles and absorbs an impact when a load of a predetermined value or more is applied in the front-rear direction of the vehicle. The frame structure of the chassis described.
A mount bracket provided at a position where the pillar member of the side member is provided and supporting the body is provided.
The mount bracket extends downward with a distance from the front and rear of the mount support portion to which the mount member connected to the body is attached, and is joined to the outer side surface of the side member in the vehicle width direction. It has a front wall part and a rear wall part,
The frame structure of the chassis according to claim 1 or 2, wherein the pillar member is joined to a side surface of the side member between the front wall portion and the rear wall portion of the mount bracket.
The extension member has an inner protrusion that protrudes toward the center from the inner end of the second cross member in the vehicle front-rear direction.
The inner protrusion is provided at a position where the inner protrusion comes into contact with the first cross member when any one of the left and right side members between the bumper frame and the first cross member is crushed. The frame structure of the chassis according to any one of claims 1 to 3.
The extension member is characterized by having a fixing portion having one end fixed to the outer end portion of the extension member in the vehicle width direction and the other end fixed to the extension portion of the bumper frame. The frame structure of the chassis according to 4.
The extension member is characterized by having a first member having an opening that opens toward the center in the front-rear direction of the vehicle, and a second member that closes at least a part of the opening of the first member. The frame structure of the chassis according to 4 or 5.
According to any one of claims 1 to 6, the second cross member is formed with a rigidity reducing portion for reducing the rigidity against a force of bending in the vehicle front-rear direction at the center in the vehicle width direction. The frame structure of the chassis described.
The extension member is
A connection portion connected to the pillar member and extending in the front-rear direction of the vehicle,
The left and right extension portions extending outward in the vehicle width direction from the outer end portion of the connection portion in the vehicle front-rear direction,
The fixing portion fixed to the outer end of the left and right extension portions in the vehicle width direction by a fixing member extending in the vertical direction of the vehicle, and the fixing portion.
Have,
The frame structure according to claim 5.