JP3309696B2 - Battery frame structure for electric vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a battery frame structure for an electric vehicle.

[0002]

2. Description of the Related Art In an electric vehicle, a vehicle-mounted battery occupies a considerable weight and a mounting space. Therefore, conventionally, for example, as shown in Japanese Patent Laid-Open Publication No. A battery frame having a dedicated rigid structure is provided, a plurality of batteries are mounted on the battery frame, and the batteries are hermetically stored between the vehicle body floor and the battery frame.

[0003]

In a battery frame, the rigidity of an outer frame composed of front, rear, left and right frames is increased by using a closed cross-section structural material, and the inner bottom of the outer frame is closed with a bottom plate. An intermediate frame that partitions the inside of the outer frame into a lattice shape is joined to the upper part, and the battery is mounted on this partitioned part,
Even if the intermediate frame is joined and arranged on the bottom plate in this way, the bottom plate has a large area, so that the center of the bottom plate tends to bend and deform due to the weight of a plurality of mounted batteries, which is disadvantageous in terms of sound vibration. It cannot be denied that it becomes.

In order to increase the rigidity of the bottom plate, it is necessary to increase the thickness of the bottom plate itself or to increase the sectional shape of the intermediate frame. However, this only increases the weight of the battery frame. In addition, the battery frame becomes bulky and layout becomes difficult in consideration of the ground height.

Accordingly, the present invention provides a battery frame structure for an electric vehicle in which the strength and rigidity of the bottom plate can be increased without increasing the weight and bulkiness, and the bending deformation of the center portion of the bottom plate can be prevented. is there.

[0006]

According to a first aspect of the present invention, there is provided an outer frame formed of front and rear, left and right frames, a bottom plate for closing an inner bottom of the outer frame, and an outer frame joined to the bottom plate. And an intermediate frame that partitions the inside of the battery pack on a lattice, and a battery is mounted on the partition portion. And a through hole is formed in a substantially central portion of the bridge frame.
And bend the flange downward at the edge of the hole
And insert a substantially cylindrical bracket into the through hole to insert
The racket is fixedly joined to the upper surface of the through hole edge and the flange.
And insert bolts through the bottom seating surface of the bracket
And the approximate center of the bridge frame is
And is fastened and fixed to the intermediate frame.

[0007]

According to a second aspect of the present invention, the bottom seating surface of the bracket according to the first aspect is positioned so as to straddle adjacent corners of the mounted battery, and a bolt is formed between these adjacent corners. The bridge frame is inserted through the gap, and a substantially central portion of the bridge frame is fastened and fixed to the intermediate frame together with the battery via the bracket.

According to a third aspect of the present invention, a battery cover for covering the mounted battery is mounted on the outer frame according to the first and second aspects, and the bridge frame is received in a portion of the battery cover corresponding to the bridge frame. The embossed recess is formed, and the inner surface of the bridge frame and the inner surface of the battery cover are flush with each other.

[0010]

According to the first aspect, the battery load acting on the central portion of the bottom plate can be distributed and loaded on the outer frame via the bolt and the bridge frame. It is possible to prevent bending deformation of the center portion of the bottom plate without enlarging the cross-sectional shape of the frame.

As a result, it is possible to improve the sound and vibration performance without increasing the weight and bulkiness of the battery frame and without bending deformation due to vibration during traveling of the central portion of the bottom plate.

Further, since the strength and rigidity of the bottom plate can be enhanced, the mounting stability of the battery can be enhanced, and the sense of quality and reliability can be further improved.

In addition , the bolt can be shortened by the length of the bracket, so that the number of fastening steps can be reduced. In addition, local deformation due to bolt fastening of the bridge frame can be prevented, and the coupling rigidity can be increased.

According to the second aspect , in addition to the effect of the first aspect , since the battery is interposed as a rigid body between the bracket and the intermediate frame, bending deformation of the bridge frame due to bolt fastening can be prevented, and coupling rigidity can be prevented. Can be further increased.

Further, since the brackets press the corners of the adjacent batteries with each other, they also function as a battery clamp, thereby avoiding an increase in the number of steps for mounting the battery.

According to the third aspect , in addition to the effects of the first and second aspects, the central portion of the battery cover can be reinforced by the bridge frame, and the battery cover itself has a reinforcing bead formed by embossing the concave portion. Since the surface rigidity is increased, the vibration of the battery cover can be suppressed, and the sound vibration performance can be further improved.

Further, since the inner surface of the battery cover and the inner surface of the bridge frame are flush with each other, the ventilation of the cooling air flowing between the upper surface of the battery and the battery cover is reduced.
There is no hindrance and the cooling performance of the battery is not hindered in any way.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings.

1 to 5, reference numeral 1 denotes a bottomed battery frame on which a plurality of batteries 14 are mounted, and an outer frame 2 comprising front and rear frames 3, 4 and left and right frames 5, 6; Bottom plate 7 for closing the inner bottom of 2
And an intermediate frame 8 joined and arranged on the bottom plate 7 to partition the inside of the outer frame 2 in a lattice shape.

The intermediate frame 8 is joined to the bottom plate 7 and extends in the front-rear direction. A plurality of front-rear frames 9 joined to the front and rear frames 3 and 4 are joined together. It comprises a plurality of vehicle width direction frames 10 extending in the width direction and joined to the left and right frames 5 and 6 in abutting manner.

A battery 14 is mounted on the intermediate frame 8 and separated from the bottom plate 7 on each of the grid-shaped portions.
Is formed.

The front frame 3 has a cooling air inlet 12 connected to each air passage 11, and the outside air taken in from an outside air duct 13 connected to the cooling air inlet 12.
1 is introduced.

The battery 14 is constituted by accommodating a plurality of battery cells (not shown) in a rectangular cell case 14a, and a plurality of vent holes (not shown) are provided on upper and lower walls of the cell case 14a. The cooling air introduced into the ventilation passage 11 is circulated upward in each cell case 14a to cool the battery cells, and the cooled air after circulating passes through a gap between a battery cover 19 and a battery upper surface described later. The air is exhausted to the outside from an exhaust duct (not shown) provided at the rear of the battery cover 19.

Front and rear frames 3, 4 and left and right frames 5,
Each of the intermediate frame 6 and the intermediate frame 8 is formed by extruding a lightweight metal material such as an aluminum alloy into a closed section.

In this embodiment, the end faces of the front and rear frames 3 and 4 abut against the side faces of the left and right frames 5 and 6 and their peripheral edges are welded and joined, so that the outer frame 2 is formed in a flat rectangular shape.

Steps 14b are formed at the four corners of the rectangular cell case 14a of the battery 14 by chamfering at an angle of 45 ° over an appropriate height from the upper surface.

A plurality of the batteries 14 are placed close to each other on the grid-partitioned portion of the intermediate frame 8, and the stepped portions 14 at the corners of the batteries 14, 14 adjacent to each other are placed.
b and 14b, the washer 15 is fixed, and the bolt 16 is passed through a gap 14c formed between the adjacent corners, so that each intersection between the front-rear direction frame 9 of the intermediate frame 8 and the vehicle width direction frame 10 is provided. Is fixedly fastened to the threaded portion 17 provided in the above.

In the frontmost portion of the battery frame 1, a junction box 18 of these batteries 14, 14 is fastened and fixed to the intermediate frame 8 by bolts 16 like the batteries 14.

The battery frame 1 has an outer frame 2
A battery case 19 made of resin fixed by a suitable fastening means is mounted on the upper surface of the battery case, and the mounted battery 14 and junction box 18 are hermetically housed.

Since the junction box 18 penetrates through the battery case 19 and protrudes upward, the penetrating portion is appropriately sealed.

The battery frame 1 on which the plurality of batteries 14 and the junction box 18 are mounted as described above.
Are attached by bolts and nuts to the lower surface of the floor frame member 21 joined to the lower surface of the floor panel 20 of the vehicle body.

The junction box 18 penetrates the floor panel 20 and protrudes toward the vehicle interior, and the protruding portion is covered with a lid 22.

Here, the battery frame 1 extends across substantially the center between the left and right frames 5 and 6 of the outer frame 2,
A bridge frame 23 that stands up in a gate shape is provided.

The bridge frame 23 is made of a lightweight metal material such as an aluminum alloy like the outer frame 2 and the like, and has a plurality of ribs 24 formed in the longitudinal direction to increase rigidity.

The lower edges of the legs of the bridge frame 23 are dropped into steps 5a, 6a formed on the upper inner edges of the left and right frames 5, 6, and are fastened and fixed by bolts (not shown).

A through hole 25 is formed at a substantially central portion of the bridge frame 23, and a substantially cylindrical bracket 26 is arranged to project downward through the through hole 25.

The outer shapes of the through hole 25 and the bracket 26 are formed in the same shape as the space surrounded by the corner chamfers of the four batteries 14 adjacent to the center mounted on the battery frame 1. A pair of flanges 25a are bent downward at the hole edge of the through hole 25 so as to face each other, while a pair of flanges 26a are bent at the upper edge of the bracket 26. The body is joined to the flange 25a, and the flange 26a is joined to the upper surface of the peripheral edge of the through hole 25 so that the load acts on each joint in a shear direction that is advantageous in terms of strength. Has been raised.

The bracket 26 is located adjacent to the central portion.
Battery 14 is inserted into the space surrounded by the corner chamfers, and the bottom seat surface 26b is
4 and 14, and is fixed over the step portions 14b, 14b. The bolt 16 for the battery clamp is used to screw the bolt 16 through the bolt insertion hole 26c in the bottom seat surface and the gap 14c between the battery corners. Screw into part 17,
A substantially central portion of the bridge frame 23 is fastened and fixed to the intermediate frame 8 together with the batteries 14 via the bracket 26.

On the other hand, the battery cover 19 has a bridge frame 2 at a portion corresponding to the bridge frame 23.
The recess 27 for receiving the battery cover 3 is embossed, and the inner surface of the bridge frame 23 and the inner surface of the battery cover 19 are flush with each other.
The inner surface of the battery protrudes in the vehicle width direction so that the cooling air flowing on the upper surface side of the battery 14 does not have a ventilation resistance.

According to the structure of the above-described embodiment, the central portion of the bridge frame 23 laid between substantially the central portions of the left and right frames 5 and 6 of the battery frame 1 and the central portion of the intermediate frame 8 joined on the bottom plate 7 A substantially cylindrical bracket 26 joined to the bridge frame 23 between
The battery load acting on the central portion of the bottom plate 7 can be distributed and burdened on the outer frame 2 having a rigid structure via the bolts 16, the bracket 26, and the bridge frame 23. .

Therefore, without increasing the thickness of the bottom plate 7 or enlarging the cross-sectional shape of the intermediate frame 8 in order to secure rigidity, the central portion of the bottom plate 7 and the intermediate frame 8 as shown by the chain line in FIG. It is possible to prevent the battery frame 1 from being flexed and deformed, and it is possible to improve the sound vibration performance by eliminating the flexure deformation due to the vibration during traveling of the central portion of the bottom plate 7 without increasing the weight and bulkiness of the battery frame 1.

In addition, since the strength and rigidity of the bottom plate 7 can be increased in this way, the mounting stability of the battery 14 can be improved, and the quality and reliability can be further improved.

On the other hand, apart from the effect on the sound vibration performance, in this embodiment, in particular, in the present embodiment, a substantially cylindrical bracket 26 is protruded below the bridge frame 23, and the bolt 16 is inserted through the bracket 26. Bridge frame 23
And the intermediate frame 8, the local deformation of the bridge frame 23 due to the bolt head can be prevented, and the coupling rigidity can be increased.

Moreover, the corner steps 14 of the four batteries 14, 14 adjacent to the center on the bottom seating surface of the bracket 26.
Since the batteries 14, 14 are pressed and fastened together with the batteries 14, 14 by the bolts 16, the batteries 14, 14 are interposed as rigid bodies between the bracket 26 and the intermediate frame 8, and the bending of the bridge frame 23 due to the fastening of the bolts 16 is performed. Deformation can be prevented, and the connection rigidity can be further increased.

Further, the bolt length can be reduced by the length of the protrusion of the bracket 26, so that the number of working steps can be reduced.
Since the bolt 16 for the battery clamp can also be used to function as a battery clamp, the connecting operation between the bridge frame 23 and the intermediate frame 8 is performed by the battery 1.
It can be avoided that the number of man-hours for mounting the battery is increased due to being incorporated as a part of the clamp work of 4, 14.

On the other hand, the central portion of the battery cover 19 can be reinforced by the bridge frame 23, and the battery cover 19 itself has a reinforcing bead formed by embossing the concave portion 27 for receiving the bridge frame 23, thereby increasing the surface rigidity. Therefore, the vibration of the battery cover 19 can be suppressed, and the sound vibration performance can be further improved.

Further, since the inner surface of the battery cover 19 and the inner surface of the bridge frame 23 are flush with each other, the ventilation of cooling air flowing between the upper surfaces of the batteries 14 and 14 and the battery cover 19 is hindered. And the cooling performance of the batteries 14 and 14 is not hindered.

[Brief description of the drawings]

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

FIG. 2 is an exploded perspective view showing a relationship between a bridge frame and a bracket according to the embodiment of the present invention.

FIG. 3 is a cross-sectional view corresponding to the line AA of FIG. 1 showing a mounted state on the vehicle body according to the embodiment of the present invention.

FIG. 4 is a cross-sectional view corresponding to the line BB of FIG. 1 showing a mounted state on the vehicle body according to the embodiment of the present invention.

FIG. 5 is a sectional view showing a connection portion between the bridge frame and the intermediate frame according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery frame 2 Outer frame 3,4 Front and rear frame 5,6 Left and right frame 7 Bottom plate 8 Intermediate frame 14 Battery 16 Bolt 19 Battery cover 23 Bridge frame 25 Through hole 25a Flange 26 Bracket 27 Recess

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60K 1/04 B62D 25/20

Claims (3)

(57) [Claims] 1. An outer frame comprising front, rear, left and right frames, a bottom plate for closing an inner bottom of the outer frame, and an intermediate frame joined on the bottom plate to partition the inside of the outer frame into a lattice. In the battery frame in which a battery is mounted on the partition part, a bridge frame that rises in a gate-shape straddling between substantially the center portions of the left and right frames of the outer frame is joined ,
A through hole is provided in the approximate center and the edge of the hole faces downward.
To form a substantially cylindrical bracket into the through hole.
And insert the bracket to the upper surface of the through hole
To the bracket and through the bottom seating surface of the bracket.
Insert the bolts and place approximately the center of the bridge frame.
Fastened and fixed to the intermediate frame via the bracket
A battery frame structure for an electric vehicle, comprising: 2. A bottom seating surface of the bracket is positioned across adjacent corners of the mounted battery and bolts are inserted through gaps formed between the adjacent corners to substantially approximate the center of the bridge frame. battery frame structure for an electric vehicle according to claim 1, characterized in that fastened to the intermediate frame with the battery via the bracket. 3. A battery cover for covering the mounted battery is mounted on the outer frame, and a concave portion for receiving the bridge frame is embossed at a portion of the battery cover corresponding to the bridge frame. The battery frame structure for an electric vehicle according to claim 1 , wherein an inner surface of the cover is flush with the inner surface of the cover.