JP7548465B2 - Vehicle battery compartment - Google Patents

Description

The present invention relates to a battery storage section of a vehicle.

2. Description of the Related Art Vehicles such as hybrid vehicles and plug-in hybrid vehicles are provided with an auxiliary battery that supplies power to auxiliary devices mounted on the vehicle, in addition to a drive battery that supplies power to a motor for driving the vehicle.
As an example of a vehicle equipped with such an auxiliary battery, there is disclosed a vehicle having a battery storage section that is recessed downwardly in the rear floor panel that defines the luggage compartment and that houses the battery (see Patent Document 1).
The battery storage section has a bottom wall on which the bottom surface of the auxiliary battery is placed and side walls rising from the periphery of the bottom wall, and an opening is provided in the center of the bottom wall for discharging unnecessary electrocoating paint during electrocoating of the battery storage section.
The auxiliary battery weighs, for example, about 14 kg. Therefore, when the vehicle is traveling on uneven roads, a large load is input from the auxiliary battery to the battery housing in the vertical direction, and therefore it is necessary to reinforce the bottom wall of the battery housing to ensure strength and rigidity.
Therefore, in the above-mentioned conventional technology, a pair of beads are provided on the bottom wall, which are formed in an upwardly convex shape on either side of the opening, and the pair of beads extend linearly parallel to each other in the fore-and-aft direction of the vehicle.

Japanese Patent Application Publication No. 2018-95110

When a vertical load is input to the bottom wall from the auxiliary battery while the vehicle is traveling, a first stress is generated by a bending moment that tries to bend the bottom wall in the fore-and-aft direction of the vehicle, and a second stress is generated by a bending moment that tries to bend the bottom wall in the vehicle width direction.
In the above-described conventional technology, since the pair of beads extend in the fore-and-aft direction of the vehicle, the pair of beads can increase the strength and rigidity against a first stress, but it is difficult to increase the strength and rigidity against a second stress, and there is room for improvement in ensuring the durability of the battery storage section.
The present invention has been developed in consideration of the above circumstances, and has an object to provide a battery storage section for a vehicle that is advantageous in terms of increasing strength and rigidity against the load input from the battery during driving, and improving durability.

In order to achieve the above object, one embodiment of the present invention provides a vehicle battery storage section that is formed in a recessed shape recessed downward in a floor panel of a vehicle and stores a battery therein, the battery storage section comprising:
The battery accommodating section comprises a bottom wall on which the battery is placed, side walls rising from the periphery of the bottom wall and surrounding the bottom wall, an opening provided in the center of the bottom wall, and a pair of upwardly convex beads provided on the bottom wall facing each other across the opening, wherein the beads include a first bead portion extending in the fore-and-aft direction or the width direction of the vehicle, and a pair of second bead portions extending from both longitudinal ends of the first bead portion toward the opening side in a direction intersecting the extension direction of the first bead portion.
In one embodiment of the present invention, the second bead on one side and the second bead on the other side of the opening are disposed with a predetermined interval therebetween.
In addition, one embodiment of the present invention is characterized in that the first bead portion has a first straight edge portion whose peripheral edge is formed in a straight line extending in the fore-and-aft direction of the vehicle or the width direction of the vehicle, and the second bead portion has a second straight edge portion whose peripheral edge is formed in a straight line extending in a direction intersecting the extension direction of the first straight edge portion.
Moreover, one embodiment of the present invention is characterized in that the inner peripheral edge of the first bead portion located on the opening side and the inner peripheral edge of the second bead portion located on the opening side are shaped to follow the outline of the opening, the first straight edge portion is formed on the outer peripheral edge of the first bead portion located opposite the opening, and the second straight edge portion is formed on the outer peripheral edge of the second bead portion located opposite the opening.
In addition, one embodiment of the present invention is characterized in that the opening is circular, and the inner peripheral edge of the first bead portion and the inner peripheral edge of the second bead portion are formed by a smooth single curve that follows the circumferential direction of the opening.
In addition, one embodiment of the present invention is characterized in that the boundary portion between the outer peripheral edge portion of the first bead portion and the outer peripheral edge portion of the second bead portion is an inclined edge portion that diagonally connects the first straight edge portion and the second straight edge portion.
In one embodiment of the present invention, the bottom wall is formed in a substantially rectangular shape having a pair of first sides that are parallel to each other and extend in a front-rear direction of the vehicle, and a pair of second sides that are parallel to each other and extend in a width direction of the vehicle, and the side walls are formed of a pair of first side walls that stand up from the pair of first sides and face each other,
The cylindrical member has a pair of second side walls which rise from the pair of second sides and face each other, and the first straight edge portion of the first bead portion extends parallel to either the first side wall or the second side wall, and the second straight edge portion of the second bead portion extends parallel to the other of the first side wall or the second side wall.
In one embodiment of the present invention, a tip end portion of the second bead portion is formed in a curved shape that is convex toward the front in the extension direction of the second bead portion.
In addition, one embodiment of the present invention is characterized in that the bottom wall is annularly recessed, with a central portion including the opening bulging downward, and the opening is positioned at the lowest position on the bottom wall.

According to one embodiment of the present invention, when the vehicle is traveling, a vertical load is input to the bottom wall from the auxiliary battery, generating a bending moment that tends to bend the first bead portion in its extension direction, and also generating a bending moment that tends to bend the second bead portion in its extension direction. In this case, the first bead portion increases the strength and rigidity of the bottom wall against the bending moment, and the second bead portion increases the strength and rigidity of the bottom wall against the bending moment.
Therefore, the strength and rigidity of the bottom wall against both the first stress and the second stress that are perpendicular to each other and occur in the bottom wall can be increased, which is advantageous in ensuring the durability of the battery tray.
Furthermore, according to one embodiment of the present invention, excess electrocoating paint can be allowed to flow from between the second bead portions into the opening during electrocoating, and the strength and rigidity of the bottom wall can be increased while ensuring the dischargeability of the electrocoating paint, which is advantageous in achieving both the dischargeability of the electrocoating paint and the durability of the battery tray.
Furthermore, according to one embodiment of the present invention, the battery storage section has a first straight edge portion and a second straight portion, which increases the strength and rigidity of the battery storage section against stress in the fore-and-aft direction or the width direction of the vehicle, making it more advantageous in ensuring the durability of the battery storage section.
Furthermore, according to one embodiment of the present invention, the inner peripheral edge of the first bead portion and the inner peripheral edge of the second bead portion are positioned along the opening and at a fixed interval between them, which is advantageous in allowing unnecessary electrocoating paint remaining around the opening to be smoothly discharged from the opening, and is also advantageous in increasing the strength and rigidity of the battery storage portion against stress in the vehicle fore-and-aft direction or vehicle width direction, thereby ensuring the durability of the battery storage portion.
Furthermore, according to one embodiment of the present invention, stress concentration at the point where the inner peripheral edge of the first bead portion and the inner peripheral edge of the second bead portion intersect can be alleviated, which is more advantageous in terms of increasing the strength and rigidity of the bottom wall against both the first stress and the second stress that are perpendicular to each other and occur in the bottom wall, and is more advantageous in terms of ensuring the durability of the battery storage section.
It is also advantageous in preventing unnecessary electrocoating paint from accumulating and remaining at the boundary between the inner peripheral edge of the first bead portion and the inner peripheral edge of the second bead portion, which is more advantageous in efficiently painting the battery storage portion.
Furthermore, according to one embodiment of the present invention, stress concentration at the point where the first straight edge portion and the second straight edge portion intersect can be alleviated, which is more advantageous in terms of increasing the strength and rigidity of the bottom wall against both the first stress and the second stress that are perpendicular to each other and occur in the bottom wall, and is more advantageous in terms of ensuring the durability of the battery storage section.
Furthermore, according to one embodiment of the present invention, it is advantageous in simplifying the structure of the battery accommodating section which is composed of a bottom wall, a pair of first side walls, and a pair of second side walls, and it is advantageous in reducing the manufacturing costs of the battery accommodating section.
Furthermore, according to one embodiment of the present invention, stress concentration at the tip of the second bead portion can be alleviated, which is more advantageous in terms of increasing the strength and rigidity of the bottom wall against both the first stress and the second stress, and is more advantageous in terms of ensuring the durability of the battery storage section.
Furthermore, according to one embodiment of the present invention, the strength and rigidity of the bottom wall around the opening can be improved, and it is advantageous for unnecessary electrocoating paint remaining on the bottom wall to be smoothly discharged from the annular recess through the opening, which is more advantageous for achieving both ensuring the durability of the battery storage section and ensuring the dischargeability of the electrocoating paint.

1 is a perspective view of a rear floor panel of a vehicle to which a battery storage unit for a vehicle according to an embodiment is applied; 2 is a plan view of a battery storage section of the vehicle according to the embodiment; FIG. 3 is a cross-sectional view taken along line AA in FIG. 2, showing the states of the battery housing of the vehicle before and after deformation when a load is input from the auxiliary battery. FIG. 2 is a perspective view showing an auxiliary battery, a battery holder, and a hook bolt.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In the following drawings, the symbol FR indicates the front of the vehicle, the symbol UP indicates the upper side of the vehicle, and the symbol HL indicates the vehicle width direction.
The vehicle battery storage portion (battery tray) according to this embodiment is applied to a vehicle equipped with an auxiliary battery, such as a hybrid vehicle or a plug-in hybrid vehicle.
The auxiliary battery supplies power to auxiliary devices mounted on the vehicle, and is provided separately from the drive battery that supplies power to the motor that drives the vehicle.

As shown in FIG. 1, the luggage compartment of a vehicle is defined by a floor panel 10 (a rear floor panel 10 in this embodiment) made of a steel plate.
The battery storage section 16 is formed by recessing the rear floor panel 10 downward, and stores an auxiliary battery 14 therein.
In this embodiment, the battery storage section 16 is formed as a separate body from the rear floor panel 10 by pressing a steel plate.
The battery storage section 16 is painted by electrocoating as described below.

As shown in Figures 1, 2, and 3, the battery accommodating section 16 is configured to include a bottom wall 24, a side wall 12, a flange 18, an opening 30 described later, and a pair of beads 36 described later.
The bottom wall 24 is a portion on which the auxiliary battery 14 is placed. In the present embodiment, the bottom wall 24 is formed in a substantially rectangular shape having a pair of first sides 2402 that are parallel to each other and extend in the front-rear direction of the vehicle, and a pair of second sides 2404 that are parallel to each other and extend in the width direction of the vehicle.
In this embodiment, the bottom wall 24 has a rectangular shape in a plan view, with a first side 2402 being the short side and a second side 2404 being the long side.

The side wall 12 is provided so as to rise from the peripheral edge of the bottom wall 24 and surround the periphery of the bottom wall 24 .
As shown in FIG. 2, in this embodiment, the side wall 12 has a pair of first side walls 20 that rise from a pair of first sides 2402 (short sides) and face each other in the vehicle width direction, and a pair of second side walls 22 that rise from a pair of second sides 2404 (long sides) and face each other in the vehicle fore-and-aft direction.
The flanges 18 protrude outward from the upper ends of the pair of first side walls 20 and the upper ends of the pair of second side walls 22 to the outside of the battery accommodating portion 16, and have a rectangular frame shape in a plan view.
The battery storage section 16 is fitted from above into an opening (not shown) formed in the rear floor panel 10, and is integrally attached to the rear floor panel 10 by welding a flange 18 to the portion of the rear floor panel 10 surrounding the opening.
In this embodiment, with the battery storage section 16 attached to the rear floor panel 10 in this manner, the battery storage section 16 is located between the two cross members 26A, 26B as shown in Figure 2. The auxiliary battery 14 stored in the battery storage section 16 is protected by the two cross members 26A, 26B.

As shown in FIGS. 2 and 3 , the bottom wall 24 includes a bottom wall main body 28 , an opening 30 , a bottom wall inclined portion 32 , an annular plate portion 34 , and a pair of beads 36 .
The bottom wall body 28 is connected to the lower ends of the pair of first side walls 20 and the pair of second side walls 22 .
The opening 30 is a portion for discharging unnecessary electrocoating paint during electrocoating. The opening 30 is provided in the center of the bottom wall body 28, and in this embodiment, the opening 30 has a circular shape.
The bottom wall inclined portion 32 is displaced downward from the bottom wall main body 28 around the opening 30 toward the opening 30. In this embodiment, the bottom wall inclined portion 32 has a conical surface shape.
The ring plate portion 34 connects the lower ends of the bottom wall inclined portions 32 and extends in the shape of a ring plate around the opening 30 , so that the opening 30 is located inside the ring plate portion 34 .
The ring plate portion 34 is located at the lowest position on the bottom wall 24 .
In other words, the bottom wall 24 has a central portion including the opening 30 that bulges downward to form an annular recess 35 , and the opening 30 is located at the lowest position on the bottom wall 24 .

The pair of beads 36 are formed in an upwardly convex shape on the bottom wall body 28 so as to face each other with the opening 30 therebetween.
As shown in FIG. 2, the pair of beads 36 are provided on either side of the bottom wall inclined portion 32, the annular plate portion 34, and the opening 30 in the vehicle width direction.
The pair of beads 36 includes a first bead portion 38 and a pair of second bead portions 40 .
An upper surface 3810 of the first bead portion 38 and an upper surface 4010 of the second bead portion 40 extend on the same plane.
The first bead portion 38 extends in the front-rear direction of the vehicle or in the width direction of the vehicle.
In the present embodiment, the first bead portion 38 has a width in the vehicle width direction and extends in the vehicle front-rear direction. In other words, the first bead portion 38 extends linearly in parallel with the extension direction of the first side wall 20.
The first bead portion 38 has a first straight edge portion 3802, a part of whose periphery is formed in a straight line extending in the front-rear direction or the width direction of the vehicle. In the present embodiment, the first straight edge portion 3802 extends in the front-rear direction of the vehicle.
The first straight edge portion 3802 is formed on the outer circumferential edge portion of the first bead portion 38 located on the opposite side to the opening 30 .
The first straight edge portion 3802 extends parallel to either the first side wall 20 or the second side wall 22. In this embodiment, the first straight edge portion 3802 extends parallel to the first side wall 20.
The pair of second bead portions 40 extend from both longitudinal ends of the first bead portion 38 toward the opening 30 in a direction intersecting (orthogonal to) the extending direction of the first bead portion 38 .
In the present embodiment, the pair of second bead portions 40 have a width in the vehicle front-rear direction and extend in the vehicle width direction. In other words, the pair of second bead portions 40 extend in directions approaching each other from both ends of the first bead portion 38 in the longitudinal direction.
The pair of second bead portions 40 are disposed at a predetermined interval between one side and the other side in the vehicle width direction across the opening 30. More specifically, the tip portions 4006 of the pair of second bead portions 40 face each other at a predetermined interval.
The pair of second bead portions 40 have second straight edge portions 4002 that are formed in a straight line shape such that part of the peripheral edge portion extends in a direction intersecting the extending direction of the first straight edge portions 3802 .
The second straight edge portion 4002 is formed on the outer circumferential edge portion of the second bead portion 40 located on the opposite side to the opening 30 .
The second straight edge portions 4002 of the pair of second bead portions 40 extend parallel to the other of the first side wall 20 or the second side wall 22. In the present embodiment, the second straight edge portions 4002 extend parallel to the second side wall 22.
The boundary between the outer circumferential edge of the first bead portion 38 and the outer circumferential edge of the pair of second bead portions 40 is an inclined edge portion 41 that diagonally connects the first straight edge portion 3802 and the second straight edge portion 4002 .

As shown in FIG. 2 , the inner peripheral edge 3804 of the first bead portion 38 located on the opening 30 side and the inner peripheral edge 4004 of the pair of second bead portions 40 located on the opening 30 side are shaped to follow the outline of the opening 30, and the inner peripheral edge 3804 of the first bead portion 38 and the inner peripheral edge 4004 of the pair of second bead portions 40 are formed by a smooth single curve that follows the circumferential direction of the opening 30.
In this embodiment, the inner peripheral edge 3804 of the first bead portion 38 and the inner peripheral edge 4004 of the pair of second bead portions 40 are formed as arcs with the opening 30 as the center.

A tip end 4006 of the second bead portion 40 is formed in a curved shape that is convex toward the front in the extension direction of the second bead portion 40 .
The tip ends 4006 of the pair of second bead portions 40 of each bead 36 face each other. A portion of the bottom wall body 28 located between the tip ends 4006 of the pair of second bead portions 40 facing each other forms a passage 2802 that connects the bottom wall body 28 located on the outside of the bead 36 with the bottom wall body 28 located on the inside of the bead 36.

Next, the electrodeposition coating of the battery storage section 16 will be described.
The battery storage section 16 is entirely immersed in the electrocoating paint, and a predetermined direct current is passed between the battery storage section 16 and an electrode immersed in the electrocoating paint, causing the electrocoating paint to adhere to the surface of the battery storage section 16 and form a coating, thereby performing electrocoating.
After the coating is formed, the battery storage section 16 is lifted up from the electrocoating paint and then dried in a position in which the pair of beads 36 face upward and the bottom wall body 28 is substantially horizontal.
At this time, unnecessary electrocoating paint remaining in the battery housing section 16 flows down from the battery housing section 16 and is discharged.

At this time, unnecessary electrocoating paint remaining on the first side wall 20, the second side wall 22, and the bottom wall 24 of the battery storage section 16 flows toward the opening 30 and is eventually discharged from the opening 30.
The unnecessary electrocoating paint then passes through the passage 2802 to the portion of the bottom wall main body 28 inside the beads 36, and flows into the bottom wall inclined portion 32 together with the electrocoating paint remaining in the portion of the bottom wall main body 28 inside the pair of beads 36, from the bottom wall inclined portion 32 to the ring plate portion 34, and is discharged from the opening 30.

Next, the installation of the auxiliary battery 14 will be described.
As shown in FIG. 4 , the auxiliary battery 14 has a rectangular parallelepiped shape and includes a rectangular bottom surface 1402 that is slightly smaller than the outline of the bottom wall 24 of the battery storage section 16, side surfaces 1404 rising from the four sides of the bottom surface 1402, and a rectangular top surface 1406 connecting the upper ends of the side surfaces 1404.
The auxiliary battery 14 has a weight of, for example, about 14 kg.
First, the bottom surface 1402 of the auxiliary battery 14 is placed on the bottom wall 24 of the battery storage section 16 , in other words, on the upper surface 3810 of the first bead portion 38 and the upper surface 4010 of the second bead portion 40 .
Next, the holder body 4202 of the battery holder 42 is placed extending onto the upper surface 1406 of the auxiliary battery 14 , and the pair of bent portions 4204 of the battery holder 42 are engaged with the step portions 1410 on the upper surface 1406 of the auxiliary battery 14 .
Next, the hook portion 4402 at the lower end of the hook bolt 44, which is suspended from the mounting pieces 4206 at both ends of the battery holder 42, is engaged with the locking bracket 46 (see Figure 1) attached to the upper part of the second side wall 22 of the battery accommodating section 16, and then the shaft portion of the hook bolt 44 is inserted through the screw insertion hole of the mounting piece 4206 of the battery holder 42 so as to protrude above the mounting piece 4206. A nut 48 is tightened to the male thread 4404 of the shaft portion protruding from the mounting piece 4206. The auxiliary battery 14 is then attached to the battery accommodating section 16 by sandwiching the auxiliary battery 14 from above and below between the battery holder 42 and the bottom wall 24 of the battery accommodating section 16.

Next, the effects will be described.
According to this embodiment, a pair of upwardly convex beads 36 are arranged on the bottom wall 24 facing each other across the opening 30, and are configured to include a first bead portion 38 extending in the fore-and-aft direction of the vehicle, and a pair of second bead portions 40 extending from both longitudinal ends of the first bead portion 38 toward the opening 30 in a direction intersecting the extension direction of the first bead portion 38.
Therefore, when the unevenness of the road surface while the vehicle is traveling causes an upward and downward load from the auxiliary battery 14 to be input to the bottom wall 24, generating a bending moment that tends to bend the first bead portion 38 in its extension direction, the strength and rigidity of the bottom wall 24 against that bending moment is increased by the first bead portions 38 of the pair of beads 36.
In addition, when the vehicle is traveling and unevenness in the road surface causes an upward and downward load from the auxiliary battery 14 to be input to the bottom wall 24, generating a bending moment that tends to bend the second bead portion 40 in its extension direction, the strength and rigidity of the bottom wall 24 against that bending moment is increased by the second bead portions 40 of the pair of beads 36.
Therefore, the strength and rigidity of the bottom wall 24 against both the first stress and the second stress that are generated in the bottom wall 24 and are perpendicular to each other can be increased, which is advantageous in ensuring the durability of the battery storage section 16.
In other words, the pair of beads 36 having a first bead portion 38 and a second bead portion 40 increase the strength and rigidity of the battery storage portion 16 against vibrations and loads in the fore-and-aft or width direction of the vehicle, which is advantageous in ensuring the durability of the battery storage portion 16.

FIG. 3 is a cross-sectional view taken along line AA of FIG.
In the drawing, the symbol A indicates the cross-sectional shape of the battery storage section 16 in the embodiment when the load of the auxiliary battery 14 is not input and the bottom wall 24 is not deformed.
Reference symbol B indicates a cross-sectional shape of the battery storage section 16 in the embodiment in which the bottom wall 24 of the battery storage section 16 is deformed due to input of the load of the auxiliary battery 14 .
Symbol C shows the cross-sectional shape of a battery storage section 16 of the conventional technology in which only a pair of beads 36 extending in the fore-and-aft direction of the vehicle are formed, in which the load of the auxiliary battery 14 is input and the bottom wall 24 is deformed.
In FIG. 3, the amount of deformation of the bottom wall 24 is exaggerated compared to the actual amount of deformation in order to make it easier to compare.
As is clear from the symbols B and C in Figure 3, the amount of deformation of the bottom wall 24 in the battery accommodating section 16 of this embodiment is suppressed compared to the amount of deformation of the bottom wall 24 in the battery accommodating section 16 of the prior art, and it can be seen that the strength and rigidity of the bottom wall 24 against the bending moment that attempts to bend the second bead portion 40 in its extension direction is ensured.

In addition, the pair of second bead portions 40 may extend from both ends of the first bead portion 38 in the longitudinal direction toward the opening 30 in a direction intersecting the extension direction of the first bead portion 38. For example, the pair of second bead portions 40 may extend from both ends of the first bead portion 38 in the longitudinal direction perpendicular to the first bead portion 38, or may extend from both ends of the first bead portion 38 in the longitudinal direction while inclining toward each other, or may extend from both ends of the first bead portion 38 in the longitudinal direction while inclining away from each other, and the first bead portion 38 and the pair of second bead portions 40 may extend in a C-shape in a plan view. Even with such a configuration, the effect is almost the same as that of the present embodiment.

In this embodiment, the pair of second bead portions 40 are arranged such that the tip portions 4006 on one side and the other side in the vehicle width direction face each other with a predetermined gap therebetween, sandwiching the opening 30 therebetween.
Therefore, during electrocoating, excess electrocoating paint can flow from between the pair of second bead portions 40 into the opening 30, which is advantageous in ensuring both the durability of the battery tray and the dischargeability of the electrocoating paint.

In addition, in this embodiment, the first bead portion 38 has a first straight edge portion 3802, a portion of whose peripheral edge is formed in a straight line extending in the fore-and-aft direction of the vehicle, and the second bead portion 40 has a second straight edge portion 4002, a portion of whose peripheral edge is formed in a straight line extending in a direction intersecting the extension direction of the first straight edge portion 3802.
Therefore, by having the first straight edge portion 3802 and the second straight edge portion 4002, the battery accommodating portion 16 increases the strength and rigidity of the battery accommodating portion 16 against stress in the fore-and-aft direction or the width direction of the vehicle, which is advantageous in ensuring the durability of the battery accommodating portion 16.

In addition, in this embodiment, the inner peripheral edge 3804 of the first bead portion 38 located on the opening 30 side and the inner peripheral edge 4004 of the second bead portion 40 located on the opening 30 side are shaped to follow the outline of the opening 30, the first straight edge portion 3802 is formed on the outer peripheral edge portion of the first bead portion 38 located opposite the opening 30, and the second straight edge portion 4002 is formed on the outer peripheral edge portion of the second bead portion 40 located opposite the opening 30.
Therefore, the inner peripheral edge 3804 of the first bead portion 38 and the inner peripheral edge 4004 of the second bead portion 40 are disposed along the opening 30 with a fixed distance therebetween.
This is advantageous in smoothly discharging unnecessary electrocoating paint remaining between the inner peripheral edge 3804 of the first bead portion 38 and the inner peripheral edge 4004 of the second bead portion 40 and the opening 30 from the opening 30.
In addition, the first straight edge portion 3802 and the second straight edge portion 4002 formed on the outer peripheral edge portion of the first bead portion 38 and the second bead portion 40 increase the strength and rigidity of the battery accommodating portion 16 against stress in the fore-and-aft direction or the width direction of the vehicle, which is advantageous in ensuring the durability of the battery accommodating portion 16.

In addition, in this embodiment, the opening 30 is circular, and the inner peripheral edge 3804 of the first bead portion 38 and the inner peripheral edge 4004 of the second bead portion 40 are formed by a smooth single curve that follows the circumferential direction of the opening 30.
Therefore, stress concentration at the point where the inner peripheral edge 3804 of the first bead portion 38 and the inner peripheral edge 4004 of the second bead portion 40 intersect can be alleviated, which is more advantageous in increasing the strength and rigidity of the bottom wall 24 against both the first stress and the second stress that are perpendicular to each other and occur in the bottom wall 24, and is more advantageous in ensuring the durability of the battery storage section 16.
In addition, since the corners at the boundary between the inner peripheral edge 3804 of the first bead portion 38 and the inner peripheral edge 4004 of the second bead portion 40 have been eliminated, this is advantageous in preventing unnecessary electrocoating paint from accumulating and remaining at the boundary between the inner peripheral edge 3804 of the first bead portion 38 and the inner peripheral edge 4004 of the second bead portion 40, and is advantageous in efficiently painting the battery storage portion 16.

In addition, in this embodiment, the boundary portion between the outer peripheral edge portion of the first bead portion 38 and the outer peripheral edge portion of the second bead portion 40 is an inclined edge portion 41 that diagonally connects the first straight edge portion 3802 and the second straight edge portion 4002.
Therefore, compared to the case where the first straight edge portion 3802 and the second straight edge portion 4002 are connected perpendicularly, stress concentration at the point where the first straight edge portion 3802 and the second straight edge portion 4002 intersect can be alleviated, which is more advantageous in terms of increasing the strength and rigidity of the bottom wall 24 against both the first stress and the second stress that are perpendicular to each other and occur in the bottom wall 24, and is more advantageous in terms of ensuring the durability of the battery storage section 16.

In addition, in this embodiment, the bottom wall 24 is formed in a substantially rectangular shape having a pair of parallel first sides 2402 extending in the fore-and-aft direction of the vehicle and a pair of parallel second sides 2404 extending in the width direction of the vehicle, the side wall 12 has a pair of first side walls 20 rising from the pair of first sides 2402 and facing each other, and a pair of second side walls 22 rising from the pair of second sides 2404 and facing each other, the first straight edge portion 3802 of the first bead portion 38 extends parallel to the first side walls 20, and the second straight edge portion 4002 of the second bead portion 40 extends parallel to the second side walls 22.
Therefore, this is advantageous in simplifying the structure of the battery accommodating section 16, which is composed of the bottom wall 24, a pair of first side walls 20, and a pair of second side walls 22, and is advantageous in reducing the manufacturing costs of the battery accommodating section 16.

In this embodiment, the tip portion 4006 of the second bead portion 40 is formed in a curved shape that is convex toward the front in the extension direction of the second bead portion 40 .
Therefore, stress concentration on the tip portion 4006 of the second bead portion 40 can be alleviated, which is more advantageous in increasing the strength and rigidity of the bottom wall 24 against both the first stress and the second stress, and is more advantageous in ensuring the durability of the battery storage section 16.

In addition, in this embodiment, the bottom wall 24 has a central portion including the opening 30 which is formed as an annular recess 35 that bulges downward, and the opening 30 is located at the lowest position on the bottom wall 24.
Therefore, this is advantageous in ensuring the strength and rigidity of the bottom wall 24 around the opening 30, and is also advantageous in smoothly discharging unnecessary electrocoating paint remaining on the bottom wall 24 from the annular recess 35 through the opening 30, making it more advantageous in achieving both the durability of the battery storage section 16 and the ability to discharging the electrocoating paint.

In this embodiment, a bottom wall inclined portion 32 and a ring plate portion 34 are provided around the periphery of the opening 30 .
Therefore, during painting, the electrocoating paint remaining on the bottom wall main body 28 around the opening 30 flows smoothly down from the bottom wall main body 28 through the bottom wall inclined portion 32 toward the ring plate portion 34 and is efficiently discharged from the opening 30.
This prevents unnecessary electrocoating paint from accumulating and remaining around the opening 30, which is advantageous for efficiently painting the battery storage section 16.

In this embodiment, the first side wall 20 and the first bead portion 38 extend parallel to the fore-and-aft direction of the vehicle. However, the present invention is of course applicable even when the first side wall 20 and the first bead portion 38 extend parallel to the vehicle width direction, and the same effects as this embodiment are achieved.
In addition, in this embodiment, the case has been described where the battery storage section 16 stores and holds an auxiliary battery 14 for a hybrid vehicle, a plug-in hybrid vehicle, or the like, but the present invention is of course also applicable to a battery tray that stores and holds a battery mounted on a vehicle such as a gasoline-powered vehicle that uses only fossil fuels as energy.

Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to such examples. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the claims, and it is understood that these naturally fall within the technical scope of the present invention. Furthermore, the components in the above embodiments may be combined in any manner as long as it does not deviate from the spirit of the invention.

This application is based on a Japanese patent application (Patent Application No. 2022-024489) filed on February 21, 2022, the contents of which are incorporated by reference into this application.

10 Rear floor panel 12 Side wall 14 Auxiliary battery 1402 Bottom surface 1404 Side surface 1406 Top surface 1410 Step portion 16 Battery storage portion 18 Flange 20 First side wall 22 Second side wall 24 Bottom wall 2402 Rectangular in plan view First side 2404 Second side 28 Bottom wall main body 2802 Passage 30 Opening 32 Bottom wall inclined portion 34 Annular plate portion 35 Annular recess 36 Pair of beads 38 First bead portion 3802 First straight edge portion 3804 Inner peripheral edge portion 3810 Top surface 40 Second bead portion 4002 Second straight edge portion 4004 Inner peripheral edge portion 4006 Tip portion 4010 Top surface 41 Inclined edge portions 26A, 26B Cross member 42 Battery holder 4202 Holder main body 4204 Bent portion 4206 Mounting piece 44 Hook bolt 4402 Hook portion 4404 Male thread 46 Locking metal fitting 48 Nut

Claims (9)

A battery storage unit for a vehicle, the battery storage unit being formed in a recessed shape recessed downward in a floor panel of the vehicle and housing a battery therein,
The battery accommodating section includes a bottom wall on which the battery is placed, a side wall rising from a peripheral edge of the bottom wall and surrounding the periphery of the bottom wall, an opening provided in the center of the bottom wall, and a pair of upwardly convex beads provided on the bottom wall so as to face each other across the opening, the beads being:
A first bead portion extending in a front-rear direction or a width direction of the vehicle;
a pair of second bead portions extending from both longitudinal ends of the first bead portion toward the opening side in a direction intersecting the extending direction of the first bead portion,
A battery storage unit for a vehicle. 2. The vehicle battery storage unit according to claim 1, wherein the second bead on one side and the second bead on the other side of the opening are disposed with a predetermined interval therebetween. The first bead portion has a first linear edge portion, a part of whose peripheral edge portion is formed in a linear shape extending in the front-rear direction or the width direction of the vehicle,
3. The battery storage section of a vehicle according to claim 1, wherein the second bead portion has a second straight edge portion formed in a straight line extending in a direction intersecting with the extension direction of the first straight edge portion, the second bead portion having a peripheral edge portion extending in a straight line. an inner peripheral edge portion of the first bead portion located on the opening side and an inner peripheral edge portion of the second bead portion located on the opening side are shaped to follow an outer shape of the opening,
the first linear edge portion is formed on an outer peripheral edge portion of the first bead portion located on the opposite side to the opening,
The battery storage unit for a vehicle according to claim 3 , wherein the second straight edge portion is formed on an outer circumferential edge portion of the second bead portion located on an opposite side to the opening portion. The opening has a circular shape,
An inner peripheral edge portion of the first bead portion and an inner peripheral edge portion of the second bead portion are formed by a smooth single curve along the circumferential direction of the opening.
5. The vehicle battery storage unit according to claim 4. a boundary portion between an outer circumferential edge portion of the first bead portion and an outer circumferential edge portion of the second bead portion is an inclined edge portion that obliquely connects the first linear edge portion and the second linear edge portion;
4. The vehicle battery storage unit according to claim 3 . The bottom wall is formed in a substantially rectangular shape having a pair of first sides that are parallel to each other and extend in a front-rear direction of the vehicle, and a pair of second sides that are parallel to each other and extend in a width direction of the vehicle,
the side walls include a pair of first side walls that rise from the pair of first sides and face each other, and a pair of second side walls that rise from the pair of second sides and face each other,
the first linear edge portion of the first bead portion extends parallel to either the first side wall or the second side wall,
4. The battery storage section of a vehicle according to claim 3 , wherein the second linear edge portion of the second bead portion extends parallel to the other of the first side wall or the second side wall. A tip end of the second bead portion is formed in a convex curved shape toward the front in the extension direction of the second bead portion.
3. The vehicle battery storage unit according to claim 1 or 2 . 3. The battery storage section of a vehicle according to claim 1, wherein the bottom wall has a central portion including the opening, the central portion being an annular recess bulging downward, and the opening is positioned at the lowest position on the bottom wall.

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