JPH07323736A - Battery mounting structure of electric vehicle - Google Patents

Abstract

PURPOSE:To provide battery mounting structure of an electric vehicle capable of temporarily fastening a battery tray on a skeletal member. CONSTITUTION:This is to fix both end parts of a battery tray 19 on which a battery 20 is placed by inserting them into a recessed part 32 from one end side, a protruded part 33 is formed on an opening 31 of the recessed part 32 along the longitudinal direction, a groove part 34 is formed on a part except for a front end and a rear end on an inner surface of the protruded part 33, a hook part 24 the head end part of which can be engaged with the inside of the groove part 34 on each of the both end parts of the battery tray 19 and a closed section part 25 along the longitudinal direction is formed at a position to place the battery 20 of the battery tray 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery mounting structure for an electric vehicle.

[0002]

2. Description of the Related Art As a conventional battery mounting structure for an electric vehicle, for example, the structures shown in FIGS. 8 and 9 are known (see Japanese Patent Laid-Open No. 5-208617).

Reference numeral 1 is a floor panel of an automobile. Below the floor panel 1, there are three skeleton members 2 along the front-rear direction,
3 and 4 are provided. The skeleton members 2, 3 and 4 have a closed cross-section structure, and cross members 5 and 6 along the vehicle width direction are provided at front and rear ends of the skeleton members 2, 3 and 4, respectively.
Are arranged.

A battery tray 7 has a plurality of batteries 8 mounted on the battery tray 7. The battery tray 7 is once removed from the vehicle body, and a plurality of batteries 8 are placed thereon. The battery tray 7 on which the battery 8 is placed is carried to the lower side of each of the frame members 2, 3 and 4 by a truck (not shown) or the like, and the mounting hole 9 of the battery tray 7 and the screw holes of the frame members 2, 3 and 4 are carried. After the 10 and 10 are aligned with each other, the two are fixed with a bolt 11. A radiating fin 7a for removing heat generated by the battery 8 is formed on the lower surface of the battery tray 7.

[0005]

However, in such a conventional technique, when the battery tray 7 on which a plurality of batteries 8 are mounted is attached to the skeleton members 2, 3, 4, the battery is Since the tray 7 is directly attached to the skeleton members 2, 3 and 4 by the bolts 11,
Installation of the battery tray 7 is very troublesome. That is, since the battery tray 7 cannot be temporarily fixed to the skeleton members 2, 3, and 4, the battery tray 7 and the skeleton member 2 of the battery tray 7 can be left in a state in which the battery tray 7 is placed on a dolly or the like. Since the screw holes 10 of 3 and 4 must be aligned, the mounting work is very difficult and its improvement is desired.

The present invention has been made in view of such a conventional technique, and provides a battery mounting structure of an electric vehicle capable of temporarily fixing a battery tray to a frame member.

[0007]

In order to achieve the above object, a battery mounting structure for an electric vehicle according to the present invention has at least a pair of skeleton members arranged in parallel with each other at a predetermined interval on a vehicle body, A recess with openings facing each other is formed in each corresponding portion of the skeleton member along the longitudinal direction from one end side of the skeleton member, and both ends of a battery tray on which a battery is mounted are inserted into the recess at one end. A battery mounting structure for an electric vehicle that is inserted and fixed from the side, wherein a convex portion is formed along the longitudinal direction in the opening of the concave portion, and a groove portion is formed on the inner surface of the convex portion other than the front end and the rear end. Then, at both ends of the battery tray, hooks are formed whose tips are engageable with the groove of the convex portion, and a closed cross section along the longitudinal direction is formed at a position where the battery is placed on the battery tray. It is intended.

[0008]

When the battery tray on which the battery is placed is lifted by, for example, a dolly, the closed cross section is vertically sandwiched by the battery and the dolly, and the width of the battery tray slightly expands. It can be inserted into the recess without interfering with the end of the part. Then, when the dolly is removed with the hook part inserted in the recess,
The width of the battery tray is slightly restored and the central part of the battery tray bends downward, so the tip of the hook part engages with the groove of the convex part and the battery tray is temporarily fixed to the frame member. Becomes Since the groove with which the tip of the hook engages is not formed at the front end and rear end of the convex part, once in the temporarily fixed state, the front end and rear end serve as stoppers, and the battery tray will not come out of the groove. .
Therefore, by finely adjusting the position of the battery tray in the temporarily fixed state, the mounting position of the battery tray can be accurately and easily aligned, and the workability of mounting the battery tray is improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to FIGS.
It will be described based on. It should be noted that the description overlapping with the conventional one is omitted.

An underfloor structure 12 constitutes the lower part of the automobile. Reference numeral 13 denotes a center member serving as a "skeleton member", and side members 14 and 15 serving as "skeleton members" are similarly arranged on both left and right sides of the center member 13. The center member 13 and the side members 14 and 15 are extruded products made of aluminum alloy and have the same rectangular cross section in the front-rear direction. In addition, the side members 14 and 15 have outwardly projecting portions 16 respectively.
Are formed on the front and rear sides, and side sill portions 17 having a closed cross-section structure are provided between the front and rear ends of the front and rear protruding portions 16, respectively.

Between the center member 13 and each of the side members 14 and 15, there are provided an upper plate 18 serving as a "floor panel" of the passenger compartment and a battery tray 19. The battery tray 19, the side surface of the center member 13, and the side surfaces of the side members 14 and 15 define a storage space 21 for storing a plurality of batteries 20. The upper plate 22 is also provided between the side members 14 and 15 and the side sill portion 17.
And a lower plate (not shown).

The upper plate 18 forming the upper part of the storage space 21 is attached to the upper surfaces of the center member 13 and the side members 14 and 15 by known fastening means such as bolts.

Next, the shape of the battery tray 19 and its mounting structure will be described.

The battery tray 19 is also an extruded product made of aluminum alloy and has the same cross-sectional shape in the longitudinal direction. Hook portions 24 are formed so as to be folded back downward at both ends of the battery tray 19, and a closed cross-section portion 25 is formed at a position corresponding to the battery 20 along the longitudinal direction. A plurality of attachment holes 26 are formed in the hook portion 24 along the longitudinal direction. The closed cross-section portions 25 are formed in two rows corresponding to the rows of the batteries 20 in order to mount the two rows of the batteries 20 in the storage space 21, and have the same cross-sectional shape. That is, the cross-sectional shape of each closed cross section 25 has a shape having two small trapezoidal bead portions 27 on the upper side and a large trapezoidal bead portion 28 on the lower side. Therefore, when a force is applied to the closed cross section 25 from above and below, the closed cross section 25 is deformed so as to expand laterally.

At the lower ends of the corresponding portions of the side member 13 and the center members 14 and 15, an upper flange 29 and a lower flange 30 are formed so as to face each other in the longitudinal direction so as to face each other. A recess 32 is formed between the flange 30 and the opening 31 facing each other. A convex portion 33 is formed at the opening 31 of the lower flange 30, and the inner surface of the convex portion 33 further has a convex portion 33.
Except for the front end 33a and the rear end 33b, a groove 34 continuous in the longitudinal direction is formed (see FIGS. 2 and 5). The groove 34 has a width with which the tip of the hook portion 24 of the battery tray 19 can be engaged, and its front-rear length is slightly longer than the hook portion 24. As a method of forming the groove portion 34, first, the groove portion 34 is formed over the entire length of the convex portion 33 by extrusion molding.
To form the front end 33a and the rear end 33b of the groove 34.
It is formed by embedding only another member. Further, mounting holes 35 corresponding to the mounting holes 26 of the hook portion 24 are formed in the upper flange 29 and the lower flange 30, respectively.

Next, a procedure for actually mounting the battery 20 will be described. First, the plurality of batteries 20 are placed on the closed cross section 25 of the battery tray 19, and the closed cross section 25 of the battery tray 19 is lifted from below by the stay 36 of the carriage. Then, it is carried as it is to the front of the storage space 21, and the hook portion 24 of the battery tray 19 and the concave portion 32 are aligned.

The battery tray 1 is provided by the stay 36 of the carriage.
When the battery 9 is lifted, the weight of the battery 20 is concentrated and applied only to the closed cross section 25, and the closed cross section 25 is sandwiched by the battery 20 and the stay 36 in the vertical direction. The width expands slightly. In this way, the tip position of the hook portion 24 in the state where the width of the battery tray 19 is widened is in a state of being positioned outside the convex portion 33 in the left-right direction. Therefore, if the battery tray 19 is horizontally moved as it is, the hook portion 24 is inserted into the concave portion 32 without interfering with the convex portion 33.

When the stay 36 of the truck is removed after inserting the hook portion 24 into the concave portion 32, the weight of the battery 20 is distributed over the entire battery tray 19, so that the width of the battery tray 19 is slightly restored. As
Since the central portion of the battery tray 19 bends downward due to the weight of the battery 20, the tips of the hook portions 24 formed at both end portions of the battery tray 19 enter into the groove portions 34 formed in the convex portions 33 of the concave portion 32. The battery tray 19 is engaged and temporarily fixed to the center member 13 and the side members 14 and 15. In this way, once in the temporarily fixed state, the groove 3 is formed on the front end 33a and the rear end 33b of the convex portion 33.
4 is not formed, the front end 33a and the rear end 3
3b serves as a stopper, and the battery tray 19 is provided with the groove 34
You will never get out of it.

Therefore, by finely adjusting the position of the battery tray 19 in the temporarily fixed state, the mounting hole 26 of the battery tray 19 and the mounting holes 35 of the upper flange 29 and the lower flange 30 can be easily and surely. Therefore, the workability of attaching both by the bolt / nut means 37 is good.

Here, with reference to FIGS. 6 and 7, the amount of lateral expansion (expansion amount) of the battery tray 19 due to the deformation of the closed cross section 25 will be described in detail. Since the closed cross section 25 of this embodiment has two trapezoidal bead portions 27 on the upper portion, first, in order to consider the amount of extension of one bead portion 27, a simple cross section as shown in FIG. Hollow hexagon 3
8 and further an arc 39 indicated by a dotted line based on this shape. As shown in FIG. 7, the arc 39 has one end fixed and the other end movable, and considering a model in which the load F acts on the arc 39 from directly above,
The amount of elongation in one bead portion 27 is calculated.

The calculation conditions are as follows. Oblique side A = 70 mm, top side B = 30 mm of hollow hexagonal body 38 in cross section,
Thickness t = 1 mm, angle θ = 45 °, load F = 20 kgf
(Since the weight of one battery 20 is 40 kg, half the weight is added.) The material is aluminum alloy.

Young's modulus E = 7000 kgf / m
m ² , radius of arc R = Acos θ + (B / 2), cross section 2
Next moment I = (t ³ b) / 12, cross-section width b = 4
If it is 00 mm, the extension amount of the arc is δx = 0.257.
7 × [(FR ³ ) / (EI) = 0.5 mm.

Since one closed cross section 25 has two bead sections 27 used as the above-described calculation model, and one battery tray 19 has two closed cross sections 25, one battery tray is provided. As a whole, the width is 0.5 × 4 = 2 m
m (each of the left and right hook portions 24 is 1 mm). However, the actual closed cross-section portion 25 is more likely to extend in the left-right direction due to stress concentration at the corners, and the actual extension amount of each hook portion 24 may be a value (1 mm + α) slightly larger than the above value. .

Since each hook portion 24 of the battery tray 19 exhibits the above-described amount of extension, considering the amount of extension,
The width size of the battery tray 19 and the width size between the left and right recesses 32 may be set.

Further, in this embodiment, when the vehicle is traveling, air enters the storage space 21 for storing the battery 20, so that the air flowing in the storage space 21 can radiate heat from the battery 20. Moreover,
Since the battery tray 19 has the closed cross section 25, the surface area of the battery tray 19 increases and
Since air also flows into the closed cross section 25, the battery 20
The heat can be dissipated more efficiently.

In addition, the closed cross section 25 has the battery tray 1
Since the battery tray 19 is continuously formed in the longitudinal direction, the rigidity of the battery tray 19 in the longitudinal direction is increased, and the bending of the battery tray 19 in the longitudinal direction can be reduced.

The closed cross section 25 has the battery tray 1
9 is formed continuously in the longitudinal direction, the closed cross section 25 is formed when an external force from the lateral direction is applied to the battery tray 19 due to a side collision of an automobile or the like.
Is mainly deformed to absorb the external force, and damage to the battery tray 19 and the battery 20 can be suppressed to the minimum.

In the above description, the center member 13, the side members 14 and 15 as the "skeletal member", and the battery tray 19 are formed by extrusion molding of aluminum alloy, but the present invention is not limited to this. However, it may be a metal other than an aluminum alloy, or a molded product other than an extruded product.

In this embodiment, each recess 32 is formed over the entire length of the center member 13 and the side members 14 and 15, but at least one hook side (in this embodiment, the hook portion 24 is inserted). Then, only the front end side) needs to be opened, and the other end side may be closed.

Further, in this embodiment, an example in which three "skeleton members" are formed and the battery tray 19 is provided between the respective skeleton members is shown, but the number of "skeleton members" is two, four or more. May be

In this embodiment, the "skeleton member" is arranged in the front-rear direction of the vehicle body, and the battery tray 19 is slid in the front-rear direction to be attached thereto. Alternatively, the battery tray 19 may be attached by sliding it in the left-right direction.

In this embodiment, the upper flange 29 and the lower flange 30 are projected and the recess 32 is formed between them. However, the upper flange 29 and the lower flange 30 are not provided, and the center member is not provided. The concave portion 32 may be provided in the side surface of 13 or the side members 14 and 15.

[0033]

The battery mounting structure of the electric vehicle according to the present invention has the contents described above.
When the battery tray on which the battery is placed is lifted by, for example, a dolly, the closed cross section is vertically sandwiched by the battery and the dolly, and the width of the battery tray is slightly expanded.
The hook portion of the battery tray can be inserted into the concave portion without interfering with the convex portion, and when the dolly is removed, the tip of the hook portion engages with the groove portion of the convex portion and is temporarily fixed. Therefore, by finely adjusting the position of the battery tray in the temporarily fixed state, the mounting position of the battery tray can be accurately and easily aligned, and the workability of mounting the battery tray is improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an underfloor structure of a battery mounting structure for an electric vehicle according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a relationship between a skeleton member and a battery tray.

FIG. 3 is a cross-sectional view taken along the line SA-SA indicated by an arrow in FIG. 1, showing a state before fixing the battery tray (however, the upper plate is omitted).

FIG. 4 is a cross-sectional view corresponding to FIG. 3 showing a state after fixing the battery tray.

FIG. 5 is an enlarged view showing a DA portion indicated by an arrow in FIG.

FIG. 6 is a shape in which one bead portion above the closed cross-section portion is simply assumed in order to calculate the amount of extension in the left-right direction.

FIG. 7 is a diagram showing an arc in which the shape of FIG. 6 is further simplified.

FIG. 8 is a sectional view of a vehicle showing a battery mounting structure of a conventional electric vehicle.

9 is a cross-sectional view taken along the line SB-SB shown in FIG.

[Explanation of symbols]

 13 Center Member (Skeletal Member) 14, 15 Side Member (Skeletal Member) 19 Battery Tray 20 Battery 24 Hook 25 Closing Section 31 Open 32 Recess 33 Convex 33a Convex Front End 33b Convex Rear End 34 Groove

Claims (4)

[Claims] 1. A skeleton member having at least a pair of skeleton members arranged in parallel with each other at a predetermined interval on a vehicle body, and a recess having openings facing each other at corresponding portions of the skeleton member from one end side of the skeleton member. A battery mounting structure for an electric vehicle, which is formed along a longitudinal direction, and inserts and fixes both ends of a battery tray on which a battery is mounted into the recess by inserting the battery tray from one end side in the longitudinal direction. A groove is formed on a portion other than the front end and the rear end on the inner surface of the convex portion along with forming a convex portion, and both ends of the battery tray have hook portions having tips that can be engaged in the groove portion of the convex portion. A battery mounting structure for an electric vehicle, characterized in that a closed cross section along the longitudinal direction is formed at the position where the battery is placed on the battery tray. 2. The electric vehicle according to claim 1, wherein the cross-sectional shape of the closed cross section is a shape having two small trapezoidal bead portions on the upper side and a large trapezoidal bead portion on the lower side. Battery mounting structure. 3. A frame member comprising a center member arranged at the center of the vehicle body and side members arranged on both left and right sides of the center member, and a battery tray is mounted between the center member and each side member. Alternatively, the battery mounting structure of the electric vehicle according to claim 2. 4. The battery mounting structure for an electric vehicle according to claim 1, wherein the frame member and the battery tray are extruded products.