VEHICLE BODY STRUCTURE OF CAB-OVER TYPE VEHICLE

A vehicle body structure of a cab-over type vehicle includes: a floor cross member extending in a vehicle width direction along a lower surface of a floor panel of a cab body and including a pair of mount portions to which mounts are attached on both sides in the vehicle width direction; and a gusset extending in a vehicle front-rear direction between the pair of mount portions below the floor panel, including one end portion joined to the lower surface of the floor panel and the other end portion joined to a lower surface of the floor cross member, and linearly connecting the lower surface of the floor panel and the lower surface of the floor cross member.

TECHNICAL FIELD

The present invention relates to a vehicle body structure of a cab-over type vehicle.

BACKGROUND ART

As a structure of a vehicle such as an automobile, there is a cab-over type vehicle in which a cab body constituting a cabin (a vehicle compartment) is supported by a chassis frame via a mount.

Patent Literature 1 discloses a cab-over type vehicle in which a cab body includes a floor panel partitioning a lower portion of a cabin, a floor cross member extending in a vehicle width direction and joined to a lower surface of the floor panel, and a pair of mount portions provided at both ends of the floor cross member in the vehicle width direction and to which mounts are attached.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

In such a cab-over type vehicle, when a load due to vibration during traveling is input to the floor cross member via the mounts, torsion occurs in the floor cross member, and thus vibration of the floor panel is likely to occur. Therefore, there is room for improvement in preventing swing and noise in the cabin and improving steering stability.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle body structure of a cab-over type vehicle which is advantageous in preventing swing and noise in a cabin and improving steering stability.

Solution to Problem

To achieve the above object, an embodiment according to the present invention provides a vehicle body structure of a cab-over type vehicle in which a cab body is supported by a chassis frame via mounts. The vehicle body structure of a cab-over type vehicle includes: a floor cross member extending in a vehicle width direction along a lower surface of a floor panel of the cab body and including a pair of mount portions to which the mounts are attached on both sides in the vehicle width direction; and a gusset extending in a vehicle front-rear direction between the pair of mount portions below the floor panel, including one end portion joined to the lower surface of the floor panel and the other end portion joined to a lower surface of the floor cross member, and linearly connecting the lower surface of the floor panel and the lower surface of the floor cross member.

Advantageous Effects of Invention

According to an embodiment of the present invention, a strength and rigidity of a floor cross member can be further improved by a gusset, and even when a load due to vibration during traveling is input to mount portions on both sides of the floor cross member, torsional deformation of the floor cross member can be prevented.

Therefore, vibration and noise in a cabin can be prevented, and rigidity of a cab body (floor panel) is improved by the gusset, which is advantageous in improving steering stability.

DESCRIPTION OF EMBODIMENTS

Hereinafter, a vehicle body structure of a cabin portion of a cab-over type vehicle according to an embodiment of the present invention will be described with reference to the drawings.

In the following drawings, a reference numeral FR denotes a vehicle front side, a reference numeral UP denotes a vehicle upper side, and a reference numeral HL denotes a vehicle width direction.

First, a configuration of a vehicle to which the present invention is applied will be described.

As shown inFIG.1, a vehicle10to which the present invention is applied is a cab-over type vehicle, and is a truck including a chassis frame12, a cab body16supported by the chassis frame12via front mounts14A and rear mounts14B, and a loading platform (not shown).

The chassis frame12supports the cab body16and the loading platform from below, and includes a pair of chassis side members18, a plurality of chassis cross members20, and a chassis bumper beam22.

InFIG.1, a portion of the chassis frame12that is located on a vehicle rear side is not shown.

The pair of chassis side members18extend in a vehicle front-rear direction at an interval in the vehicle width direction.

The plurality of chassis cross members20extend in the vehicle width direction at an interval in the vehicle front-rear direction, and both ends thereof are joined to the pair of chassis side members18.

In the present embodiment, the chassis cross members20includes a front side chassis cross member20A disposed between the chassis side members18on the vehicle front side, and a rear side chassis cross member20B disposed between the chassis side members18below a vehicle rear side portion of a cabin.

The chassis bumper beam22extends in the vehicle width direction and joins front ends of the pair of chassis side members18.

A pair of front mount portions24A are provided at positions of the pair of chassis side members18on the vehicle front side.

The pair of front mount portions24A includes chassis side front brackets23A disposed on the chassis side members18, and a pair of front mounts14A disposed on the chassis side front brackets23A and formed of an elastic member such as rubber.

A pair of rear mount portions24B is provided at positions of the pair of chassis side members18corresponding to the cabin on the vehicle rear side.

The pair of rear mount portions24B includes chassis side rear brackets23B disposed on upper surfaces of the chassis side members18, and a pair of rear mounts14B disposed on the chassis side rear brackets23B and formed of an elastic member such as rubber.

The cab body16includes a cabin frame (not shown) and a cabin main body30including a floor panel28that partitions a lower portion of the cabin.

The cabin frame is provided on a lower surface of the floor panel28, may be molded integrally with the floor panel28, or may be molded separately and attached to the floor panel28.

The cabin frame includes a pair of floor side members (not shown) and a plurality of floor cross members.

The pair of floor side members extends in the vehicle front-rear direction at an interval in the vehicle width direction on an inner side in the vehicle width direction relative to the chassis side members18, and has a length from the vicinity of a front end of the cab body16to a central portion of the cab body16in the vehicle front-rear direction.

The plurality of floor cross members extend in the vehicle width direction at an interval in the vehicle front-rear direction.

The plurality of floor cross members include a rear floor cross member36(seeFIG.2) that is provided at the floor panel28at a position that is separated rearward from rear ends of the floor side members, and at least one floor cross member (not shown) including both ends joined to the pair of floor side members at a front side relative to the rear floor cross member36.

As shown inFIG.2, a pair of floor side rear brackets40that are attached to the rear mount portions24B (the rear mounts14B) are provided at both end lower portions of the rear floor cross member36.

In the present embodiment, the rear floor cross member36extends in the vehicle width direction along a lower surface of the floor panel of the cab body, and corresponds to a floor cross member including mount portions to which mounts are attached on both sides in the vehicle width direction.

InFIG.2, a reference numeral26denotes side sills extending in the vehicle front-rear direction at an interval in the vehicle width direction, and both ends of the floor panel28in the vehicle width direction and both ends of the rear floor cross member36in the vehicle width direction are joined to the side sills26.

The cabin main body30includes the floor panel28that partitions the lower portion of the cabin, a front panel42that stands upright from a front portion of the floor panel28, a pair of side panels44that stand upright from both sides of the floor panel28in the vehicle width direction, a back panel46that stands upright from a rear portion of the floor panel28, and a roof panel (not shown) that connects upper ends of the panels.

In the present embodiment, the lower surface of the floor panel28is joined by welding to the pair of floor side members and the plurality of cross members including the rear floor cross member36.

As shown inFIG.2, in the present embodiment, front seats48and a rear seat50disposed behind the front seats48are disposed in the cabin.

The front seats48include a driver seat and a passenger seat.

The rear seat50is a bench seat on which three occupants can sit, and is disposed above the rear floor cross member36.

InFIG.2, a reference numeral T denotes a front wheel.

As shown inFIG.1, the floor panel28includes a front floor panel28A and a rear floor panel28B that is connected to a rear portion of the front floor panel28A and is displaced further upward than the front floor panel28A.

The front seats48are disposed above the front floor panel28A, and the rear seat50is disposed above the rear floor panel28B.

Positions on both sides of a front portion of the front floor panel28A are attached to the pair of front mount portions24A (the front mounts14A) via a pair of floor side front brackets (not shown). Therefore, the positions on the both sides of the front portion of the front floor panel28A are supported by the chassis frame12via the pair of front mount portions24A (the front mounts14A).

As shown inFIGS.2and3, the rear floor cross member36is joined to a lower surface of a rear end of the rear floor panel28B via a reinforcement52.

Specifically, the reinforcement52is provided between the rear floor cross member36and the rear floor panel28B, and extends in the vehicle front-rear direction while overlapping the rear floor panel28B from the rear floor cross member36.

As shown inFIG.3, the reinforcement52has a hat-shaped cross-section open upward.

The reinforcement52includes a reinforcement lower surface portion5202, a reinforcement front surface portion5204, a reinforcement rear surface portion5206, a reinforcement front flange portion5208, a reinforcement rear flange portion5210, and a reinforcement rear standing portion5212.

The reinforcement lower surface portion5202is located at a lowest level among the portions constituting the reinforcement52.

The reinforcement front surface portion5204stands from a vehicle front end of the reinforcement lower surface portion5202, and the reinforcement rear surface portion5206stands from a vehicle rear end of the reinforcement lower surface portion5202.

The reinforcement front flange portion5208extends toward the vehicle front side from an upper end of the reinforcement front surface portion5204, and overlaps a lower surface2802of the rear floor panel28B.

In other words, the reinforcement52extends toward the vehicle front side from the rear floor cross member36while overlapping the rear floor panel28B.

The reinforcement front flange portion5208is formed such that a width of the reinforcement front flange portion5208along the vehicle front-rear direction is larger than a width of the reinforcement lower surface portion5202along the vehicle front-rear direction.

The reinforcement rear flange portion5210extends toward the vehicle rear side from an upper end of the reinforcement rear surface portion5206and overlaps the lower surface2802of the rear floor panel28B.

The reinforcement rear standing portion5212stands upward from a rear end of the reinforcement rear flange portion5210, and overlaps a standing portion2804at a rear end of the rear floor panel28B from the vehicle rear side.

As shown inFIG.3, the rear floor cross member36has a hat-shaped cross-section open upward.

The rear floor cross member36includes a cross member lower surface portion3602, a cross member front surface portion3604, a cross member rear surface portion3606, a cross member front flange portion3608, a cross member rear flange portion3610, and a cross member rear standing portion3612.

The cross member lower surface portion3602is located at a position spaced apart from the reinforcement lower surface portion5202below the reinforcement lower surface portion5202.

The cross member front surface portion3604stands upright from a vehicle front end of the cross member lower surface portion3602, and is located at a position away from a vehicle front side of the reinforcement front surface portion5204.

The cross member rear surface portion3606stands upright from a vehicle rear end of the cross member lower surface portion3602, and is located at a position away from a vehicle rear side of the reinforcement rear surface portion5206.

The cross member front flange portion3608extends forward from an upper end of the cross member front surface portion3604and overlaps a lower surface of the reinforcement front flange portion5208.

The cross member front flange portion3608is formed such that a width of the cross member front flange portion3608along the vehicle front-rear direction is smaller than a width of the reinforcement front flange portion5208along the vehicle front-rear direction. The cross member rear flange portion3610extends rearward from an upper end of the cross member rear surface portion3606and overlaps a lower surface of the reinforcement rear flange portion5210.

The cross member rear standing portion3612stands upward from a rear end of the cross member rear flange portion3610and overlaps the reinforcement rear standing portion5212from the vehicle rear side.

The reinforcement front flange portion5208and the cross member front flange portion3608overlap the lower surface2802of the rear floor panel28B and are joined by welding in a three-layer manner, and the reinforcement rear flange portion5210and the cross member rear flange portion3610overlap the lower surface2802of the rear floor panel28B and are joined by welding in a three-layer manner.

As shown inFIGS.1and2, both ends of the cross member lower surface portion3602in the vehicle width direction are attached to the pair of rear mount portions24B (the rear mounts14B) via the pair of floor side rear brackets40. Therefore, the both ends of the rear floor cross member36are supported by the chassis frame12via the pair of rear mount portions24B (the rear mounts14B).

Therefore, the cab body16is supported by the chassis frame12via the front mounts14A and the rear mounts14B.

Next, an attachment structure of the rear seat50will be described.

As shown inFIG.3, the rear seat50includes a seat cushion5002on which the occupant sits, and a seat back5004standing from a rear portion of the seat cushion5002and serving as a backrest for the occupant.

The seat cushion5002includes a seat cushion frame5006constituting a frame of the seat. The seat back5004includes a seat back frame5008constituting a frame of the seat.

The seat cushion frame5006and the seat back frame5008are connected to a shaft54extending in the vehicle width direction at a position below a rear portion of the seat cushion5002.

Both ends of the shaft54in an extending direction are attached to the rear floor panel28B via a pair of seat attachment members56.

As shown inFIG.3, each of the seat attachment members56includes a connecting plate5602that is welded to an outer periphery of the shaft54and extends downward, and an attachment piece5604that protrudes outward in the vehicle width direction from a lower end of the connecting plate5602.

The attachment piece5604has a bolt insertion hole5606.

A stud bolt58that passes through the rear floor panel28B and protrudes upward is provided at a position of the reinforcement front flange portion5208corresponding to the bolt insertion hole5606of the attachment piece5604.

The stud bolt58is inserted through the bolt insertion hole5606of the attachment piece5604, a nut60is fastened to the stud bolt58, and the seat attachment member56is attached to the rear floor panel28B. Therefore, the rear seat50is attached to the rear floor panel28B via the shaft54and the seat attachment members56.

Therefore, in the present embodiment, the stud bolt58forms a seat attachment portion62that is provided at a position of the floor panel28and that is used for attaching a seat frame (the seat cushion frame5006and the seat back frame5008) forming the rear seat50. The seat attachment portion62is provided at a position at which the reinforcement52and the rear floor panel28B overlap each other on the vehicle front side of the rear floor cross member36and on the vehicle rear side relative to a position of the reinforcement52on the vehicle front side.

In other words, the seat attachment portion62is provided at the position at which the reinforcement52and the rear floor panel28B overlap each other, at one end portion side of the reinforcement52relative to the rear floor cross member36and at a rear floor cross member36side relative to one end portion of the reinforcement52in the vehicle front-rear direction.

Further, in a plan view, the seat attachment portion62(the stud bolt58) is provided at a position of the floor panel28that is located inside a contour of a gusset76to be described later.

As shown inFIG.5, the rear seat50is provided with three three-point seat belt devices64corresponding to the three occupants.

The seat belt device64includes a seat belt (not shown), a seat belt anchor (not shown), a retractor (not shown), a tongue (not shown), a buckle66, and a buckle anchor68.

The seat belt restrains the occupant seated on the rear seat50at a time of a collision, and one end of the seat belt is attached to a cab body16side via the seat belt anchor.

The retractor accommodates the other end of the sheet belt to be able to wind and unwind.

The tongue is provided at an intermediate portion of the seat belt.

The tongue is inserted into and removed from the buckle66, and the buckle66is detachably connected to the tongue. The buckle66is attached to a cab body16side via the buckle anchor68.

The buckle66is disposed toward a front side relative to the gusset76to be described later in the vehicle front-rear direction.

In the present embodiment, the seat belt anchors (not shown) of the seat belt devices64of left and right seats included in the rear seat50are attached to the rear floor panel28B. As shown inFIG.5, the buckle anchor68is attached to the rear floor panel28B.

Further, the seat belt anchor (not shown) of the seat belt device64of a center seat included in the rear seat50is attached to a position of the rear floor panel28B. As shown inFIG.5, the buckle anchor68is attached to the rear floor panel28B.

As shown inFIG.5, the buckle66is connected to the buckle anchor68via a connecting member6602, and a first bolt insertion hole6802is provided in the buckle anchor68.

Second and third bolt insertion holes2820and5220are respectively formed at positions of the rear floor panel28B and the reinforcement front flange portion5208corresponding to the first bolt insertion hole6802of the buckle anchor68. A plate nut70is provided coaxially with the second and third bolt insertion holes2820and5220at the lower surface of the reinforcement front flange portion5208.

A bolt72is inserted through the first bolt insertion hole6802of the buckle anchor68, the second bolt insertion hole2820of the rear floor panel28B, and the third bolt insertion hole5220of the reinforcement front flange portion5208. The buckle anchor68is attached to the rear floor panel28B by the bolt72being fastened to the plate nut70.

Therefore, in the present embodiment, the plate nut70forms an anchor attachment portion74for attaching the buckle anchor68. Then, the anchor attachment portion74is provided at a position at which the reinforcement52and the rear floor panel28B overlap each other on the vehicle front side of the rear floor cross member36and on the vehicle rear side relative to the position of the reinforcement52on the vehicle front side.

In other words, the anchor attachment portion74is provided at the position at which the reinforcement52and the rear floor panel28B overlap each other on the one end portion side of the reinforcement52relative to the rear floor cross member36and on the rear floor cross member36side relative to the one end portion of the reinforcement52in the vehicle front-rear direction.

Further, in the plan view, the anchor attachment portion74(the plate nut70) is provided at a position of the floor panel28which is located inside the contour of the gusset76(seeFIG.2) to be described later.

As shown inFIGS.2and6, a plurality of the gussets76are provided from a position of the rear floor cross member36sandwiched between the pair of rear mount portions24B (the floor side rear brackets40) to the position of the rear floor panel28B located on the vehicle front side of the rear floor cross member36. In the present embodiment, four gussets76are provided at an interval in the vehicle width direction.

As shown inFIGS.2to5, the gusset76is provided from positions of the cross member lower surface portion3602and the cross member front surface portion3604of the rear floor cross member36to a position of the lower surface2802of the rear floor panel28B located on the vehicle front side of the rear floor cross member36.

Specifically, the gusset76extends in the vehicle front-rear direction between the pair of rear mount portions24B below the rear floor panel28B. One end portion of the gusset76is joined to the lower surface2802of the rear floor panel28B. The other end portion of the gusset76is joined to a lower surface (the cross member lower surface portion3602) of the rear floor cross member36. The gusset76linearly connects the lower surface2802of the rear floor panel28B and the lower surface of the rear floor cross member36.

Further, as shown inFIG.5, the gusset76extends linearly from the lower surface (the cross member lower surface portion3602) of the rear floor cross member36to the lower surface2802of the rear floor panel28B in a forward and obliquely upward direction.

As shown inFIGS.6,7A, and7B, the gusset76includes a central portion78extending linearly and a flange portion80provided around an entire periphery of the central portion78.

The central portion78includes a bottom portion7802and a pair of side portions7804.

The flange portion80extends from the bottom portion7802and end portions of the side portions7804along the cross member front surface portion3604, which is a side surface of the rear floor cross member36, and the lower surface2802of the rear floor panel28B. The flange portion80includes a first flange8002, a second flange8004, third flanges8006, fourth flanges8008, fifth flanges8010, and sixth flanges8012.

As shown inFIGS.3,5,6,7A, and7B, in a state in which the gusset76is attached to the cross member front surface portion3604, the cross member lower surface portion3602, and the lower surface2802of the rear floor panel28B, the bottom portion7802extends obliquely in the vehicle front-rear direction, and the bottom portion7802has an inclination that is displaced downward from the vehicle front side toward the vehicle rear side.

In other words, the bottom portion7802has a predetermined width in the vehicle width direction, and extends linearly from the lower surface (the cross member lower surface portion3602) of the rear floor cross member36to the lower surface2802of the rear floor panel28B.

The first flange8002protrudes toward the vehicle front side from an edge of the bottom portion7802located on the vehicle front side. The second flange8004protrudes toward the vehicle rear side from an edge of the bottom portion7802located on the vehicle rear side. The first and second flanges8002and8004are formed by curved surfaces protruding downward.

As shown inFIGS.6,7A, and7B, the pair of side portions7804stand upward from edges of the bottom portion7802on both sides which are located on both sides in the vehicle width direction.

In other words, each of the side portions7804extends from an end portion of the bottom portion7802toward a side surface of the rear floor cross member36on one end side in the vehicle width direction and the lower surface2802of the rear floor panel28B.

Specifically, each of the side portions7804includes a front side surface7804A that is provided at a position of the side portion7804on the vehicle front side and becomes higher as it goes toward the vehicle rear side, a rear side surface7804B that is provided at a vehicle rear end of the side portion7804and becomes lower rapidly as it goes toward the vehicle rear side, and an intermediate side surface7804C that connects the front side surface7804A and the rear side surface7804B.

Each of the third flanges8006protrudes outward in the vehicle width direction from an edge of the front side surface7804A of each of the side portions7804, and is connected to the first flange8002.

Each of the fourth flanges8008protrudes outward in the vehicle width direction from an edge of the intermediate side surface7804C of each of the side portions7804, and is connected to the third flange8006.

Each of the fifth flanges8010protrudes outward in the vehicle width direction from an edge of the rear side surface7804B of each of the side portions7804, and is connected to the fourth flange8008.

Each of the sixth flanges8012protrudes toward the vehicle rear side from a lower end of each of the fifth flanges8010, and is connected to the second flange8004.

As shown inFIG.3, a space S1is formed between a curved surface of the first flange8002and the lower surface of the reinforcement front flange portion5208, and when electrodeposition coating is performed in a state in which the rear floor panel28B, the reinforcement52, the rear floor cross member36, and the gussets76are joined, a coating liquid is circulated inside the gussets76via the space S1.

As shown inFIG.3, a space S2is formed between a curved surface of the second flange8004and a lower surface of the cross member lower surface portion3602, and when the electrodeposition coating is performed in the state in which the rear floor panel28B, the reinforcement52, the rear floor cross member36, and the gussets76are joined, the coating liquid is circulated inside the gussets76via the space S2.

As shown inFIG.4, the third flange8006overlaps and is welded to the lower surface2802of the rear floor panel28B via the reinforcement front flange portion5208. Therefore, the third flange8006, the first flange8002, the reinforcement front flange portion5208, and the rear floor panel28B overlap with one another and are joined in a three-layer manner.

That is, a position of the gusset76on the vehicle front side overlaps from below a position on the vehicle front side of the reinforcement52overlapping the rear floor panel28B, and is joined by welding together with the rear floor panel28B and the reinforcement52.

In other words, the one end portion of the gusset76overlaps from below one end portion in the vehicle front-rear direction of the reinforcement52overlapping the rear floor panel28B, and is joined together with the rear floor panel28B and the reinforcement52.

As shown inFIG.4, when viewed in the vehicle width direction, the fourth flange8008forms a triangular space S3between the lower surface2802of the rear floor panel28B and the cross member front surface portion3604.

Therefore, when the electrodeposition coating is performed in the state in which the rear floor panel28B, the reinforcement52, the rear floor cross member36, and the gussets76are joined, the coating liquid is circulated inside the gussets76via the space S3.

The fifth flange8010overlaps and is welded to a lower portion of the cross member front surface portion3604, and therefore the fifth flange8010and the cross member front surface portion3604overlap each other and are joined in a two-layer manner.

The sixth flange8012overlaps and is welded to the cross member lower surface portion3602, and therefore the sixth flange8012and the cross member lower surface portion3602overlap each other and are joined in a two-layer manner.

InFIGS.3,6,7A, and7B, a reference numeral7801denotes holes formed in the bottom portion7802of the central portion78. The holes7801allow the coating liquid to flow through insides of the gussets76through the holes7801when the electrodeposition coating is performed in the same manner as described above.

As shown inFIGS.4and6, in the present embodiment, on a position of the cross member lower surface portion3602to which the sixth flanges8012are welded, a recess3620that is recessed upward relative to another position of the cross member lower surface portion3602is formed. Surface rigidity of the cross member lower surface portion3602to which the sixth flanges8012are welded is increased by the recess3620, and a joining strength between the gussets76and the rear floor cross member36is improved.

In other words, as shown inFIGS.4and6, on one end portion of the lower surface of the rear floor cross member36in the vehicle front-rear direction, a step3620A that extends in the vehicle width direction and a step surface3620B that is a lower surface on one end side in the vehicle front-rear direction relative to the step3620A and larger in height than a lower surface on the other end side in the vehicle front-rear direction relative to the step3620A are formed.

Further, the sixth flanges8012(the other end portions) of the gusset76are joined to the step surface3620B.

Next, functions and effects will be described.

According to the present embodiment, the gusset76is provided that extends between the pair of rear mount portions24B below the rear floor panel28B in the vehicle front-rear direction, includes one end portion joined to the lower surface2802of the rear floor panel28B, includes the other end portion joined to the lower surface (the cross member lower surface portion3602) of the rear floor cross member36, and linearly connects the lower surface2802of the rear floor panel28B and the lower surface of the rear floor cross member36.

Therefore, a strength and rigidity of the rear floor cross member36can be increased by the gussets76, which is advantageous in preventing torsional deformation of the rear floor cross member36even when a load due to vibration during traveling is input to the rear mount portions24B on both sides.

Therefore, vibration and noise in the cabin can be prevented, and rigidity of the cab body16(the rear floor panel28B) is improved by the gussets76, which is advantageous in improving steering stability.

Further, in the present embodiment, on the one end portion of the lower surface of the rear floor cross member36in the vehicle front-rear direction, the step3620A and the step surface3620B that is a lower surface larger in height than the lower surface on the other end side in the vehicle front-rear direction relative to the step3620A are formed. The sixth flanges8012(the other end portions) of the gusset76are joined to the step surface3620B.

Therefore, by increasing the rigidity of the rear floor cross member36by the step3620A and the step surface3620B, it is more advantageous in preventing the torsional deformation of the rear floor cross member36, and a shift of an attachment position of the gusset76with respect to the rear floor cross member36can be prevented by the step3620A at a time of an attachment operation of the gusset76, which is advantageous in improving workability.

Further, in the present embodiment, since the seat attachment portion62for attaching the rear seat50is provided at the position of the rear floor panel28B which is located inside the contour of the gusset76in the plan view, a strength and rigidity of a position of the rear floor panel28B at which the seat attachment portion62is provided are improved by the gusset76, which is advantageous in preventing an amount of movement of the seat attachment portion62toward the vehicle front side at a time of a frontal collision of the vehicle10and which is advantageous in improving evaluation in a frontal collision test.

Further, in the present embodiment, since the anchor attachment portion74on which the buckle anchor68is attached is provided at the position of the rear floor panel28B which is located inside the contour of the gusset76in the plan view, a strength and rigidity of a position of the rear floor panel28B at which the anchor attachment portion74is provided are improved by the gusset76, which is advantageous in preventing an amount of movement of the anchor attachment portion74toward the vehicle front side at the time of the frontal collision of the vehicle10and which is advantageous in improving the evaluation in the frontal collision test.

Further, in the present embodiment, the buckle66is disposed on a front side relative to the gusset76in the vehicle front-rear direction, and the gusset76extends linearly from the lower surface (the cross member lower surface portion3602) of the rear floor cross member36to the lower surface2802of the rear floor panel28B in the forward and obliquely upward direction.

Therefore, an extending direction of the gusset76and a load direction of the seat belt to which a burden is applied via the buckle66at a time of a collision coincide with each other, which is advantageous in preventing deformation of the gusset76due to the load burden.

Further, in the present embodiment, the reinforcement52extends in the vehicle front-rear direction while overlapping the rear floor panel28B from the rear floor cross member36. The one end portion of the gusset76overlaps from below the one end portion in the vehicle front-rear direction of the reinforcement52overlapping the rear floor panel28B, and is joined together with the rear floor panel28B and the reinforcement52.

Therefore, connection between the gusset76and the rear floor cross member36is further reinforced by the reinforcement52, which is advantageous in reinforcing peripheries of the gusset76and the rear floor cross member36.

Further, in the present embodiment, the seat attachment portion62is provided at the position at which the reinforcement52and the rear floor panel28B overlap each other on the one end portion side of the reinforcement52relative to the rear floor cross member36and on the rear floor cross member36side relative to the one end portion of the reinforcement52.

Therefore, the strength and the rigidity of the position of the rear floor panel28B on which the seat attachment portion62is attached are improved by the reinforcement52, which is further advantageous in improving the evaluation in the frontal collision test.

Further, in the present embodiment, the anchor attachment portion74is provided at the position at which the reinforcement52and the rear floor panel28B overlap each other on the one end portion side of the reinforcement52relative to the rear floor cross member36and on the rear floor cross member36side relative to the one end portion of the reinforcement52.

Therefore, the strength and the rigidity of the position of the rear floor panel28B at which the anchor attachment portion74is provided are improved by the reinforcement52, which is advantageous in preventing the amount of movement of the anchor attachment portion74toward the vehicle front side at the time of the frontal collision of the vehicle10and which is advantageous in improving the evaluation in the frontal collision test.

Further, in the present embodiment, the gusset76includes the bottom portion7802having the predetermined width in the vehicle width direction and extending linearly from the lower surface (the cross member lower surface portion3602) of the rear floor cross member36to the lower surface2802of the rear floor panel28B, the side portions7804each extending from the end portion of the bottom portion7802toward the side surface of the rear floor cross member36on the one end side in the vehicle width direction and the lower surface2802of the rear floor panel28B, and the flange portion80extending from the bottom portion7802and end portions of the side portions7804along the cross member front surface portion3604, which is the side surface of the rear floor cross member36, and the lower surface2802of the rear floor panel28B.

Therefore, it is advantageous in improving rigidity around attachment portions of the rear floor panel28B and the rear floor cross member36to which the gussets76are attached.

The present embodiment discloses a case where the one end portion of the gusset76is joined to the lower surface2802of the rear floor panel28B in front of the rear floor cross member36, However, the one end portion of the gusset76may be joined to the lower surface2802of the rear floor panel28B at rear of the rear floor cross member36, and the floor cross member to which the gusset76is joined may be a floor cross member other than the rear floor cross member36.

Even in this case, there is no need to say that the same operations and effects as those according to the embodiment are exhibited.

The present application is based on Japanese patent application No. 2021-056634 filed on Mar. 30, 2021, and contents thereof are incorporated herein as reference.

REFERENCE SIGNS LIST