Abstract: According to a body structure of the present invention, a floor panel member is reinforced by a pair of first members, and the second member comprised of plural pipes is disposed along the width of a vehicle so as to integrate the first members. An end of the second member is extended along the longitudinal side of the vehicle and is fixed by welding in the state of penetrating into a side sill. There is no necessity of providing any reinforcement material because the second member has a high strength continuously along the width of the vehicle. Moreover, there is no necessity of increasing a board thickness for the purpose of securing the rigidity because the second member penetrates into the side sill. On the other hand, the second member can be manufactured by cutting an existing steel pipe to a predetermined side. It is therefore possible to cope with the change in the width of the vehicle only by changing a cutting size.

Abstract: A front side member extending in the longitudinal direction of a vehicle is comprised of a kick up portion, and a cylindrical front side member body with an octagonal sectional form extending from the front end to the rear end in front of the kick up portion. The kick up portion and the front side member body are integrated together by joining an inner member and an outer member. The respective portions of the inner member and the outer member between the kick up portion and the front side member are concaved to be in contact with each other, and are welded together to form a joint. A first closed section is formed at the upper side of the joint, and a second closed section is formed at the lower side of the joint. The result realizes a vehicle body structure having a lightweight front side member with an improved impact resistance and a high energy absorbing efficiency.

Abstract: A front side member extending in the longitudinal direction of a vehicle is comprised of a kick up portion, and a cylindrical front side member body with an octagonal sectional form extending from the front end to the rear end in front of the kick up portion. The kick up portion and the front side member body are integrated together by joining an inner member and an outer member. The respective portions of the inner member and the outer member between the kick up portion and the front side member are concaved to be in contact with each other, and are welded together to form a joint. A first closed section is formed at the upper side of the joint, and a second closed section is formed at the lower side of the joint. The result realizes a vehicle body structure having a lightweight front side member with an improved impact resistance and a high energy absorbing efficiency.

Abstract: A pair of cylindrical impact absorbing members, which is unintegrated with side members and is formed to have a substantially equilateral octagonal sectional form, is fixed on the side members in such a manner as to extend forward from the side members. Since the impact absorbing members are unintegrated with the side members, the impact absorbing members can be formed of optimum material with an optimum board thickness and can be formed to have an ideal sectional form by an optimum forming process under no restriction from a manufacturing method and the like for the side member.

Abstract: According to a body structure of the present invention, a floor panel member is reinforced by a pair of first members, and the second member comprised of plural pipes is disposed along the width of a vehicle so as to integrate the first members 1. An end of the second member is extended along the longitudinal side of the vehicle and is fixed by welding in the state of penetrating into a side sill. There is no necessity of providing any reinforcement material because the second member has a high strength continuously along the width of the vehicle. Moreover, there is no necessity of increasing a board thickness for the purpose of securing the rigidity because the second member penetrates into the side sill. On the other hand, the second member can be manufactured by cutting an existing steel pipe to a predetermined side, and it is therefore possible to cope with the change in the width of the vehicle only by changing a cutting size.