Body structure for a light tricycle-type vehicle equipped with a battery pack protection device

Abstract

The invention relates to a welded steel body structure (100) for a light electric vehicle of the tricycle type, comprising a subframe (110) including two side members (111, 112), two front (113) and rear cross members extending fixedly between the front and rear ends of said side members, a central side member (114) extending fixedly between said front and rear cross members, and an intermediate reinforcing cross member (115) extending fixedly between said side members, said structure also comprising a box (130) defining a housing for a propulsion battery pack (B) and having a chassis comprising an upper frame (132) supported in particular by two uprights (133, 134) extending fixedly between said intermediate reinforcing cross member (115) and the front edge of said upper frame, being arranged on either side of said central side member,said structure further comprising a protective device (150) including a metal apron extending fixedly between said uprights. Figure to be published with the abbreviation: Fig. 2,

Description

Title of the invention: Body structure for a light tricycle-type vehicle equipped with a battery pack protection device technical field

[0001] The invention relates generally to lightweight, electrically powered tricycle-type vehicles with a compact size particularly suited to urban use. More specifically, it relates to a welded steel body structure for such a vehicle. Previous technique

[0002] The continued increase in the number of vehicles in circulation poses many congestion problems related to the movement and parking of these vehicles, particularly in city centre areas.

[0003] In order to facilitate traffic and parking, an ever-increasing number of users are turning to motorized two-wheeled vehicles such as motorcycles or scooters, but these do not offer the same level of safety and protection against the weather to the driver and any passenger.

[0004] For these reasons, recent years have seen the appearance on the market of light electric-powered tricycle-type vehicles whose reduced dimensions are particularly suited to use in urban environments.

[0005] These light tricycle-type vehicles are generally equipped with a welded body structure classically comprising a subframe including two side rails, two front and rear cross members extending fixedly between the front and rear ends of said side rails, a central side rail extending fixedly between said front and rear cross members, and an intermediate reinforcing cross member extending fixedly on either side of the central side rail between the side rails.

[0006] Such a body structure also includes a cab sub-assembly resting on the front part of the underbody and comprising a central strut intended to support the steering column and extending diagonally upwards and forwards from the central area of ​​the front crossmember and the front end of the central side member of the underbody.

[0007] The rear portion of such a cab sub-assembly may further include a box defining a housing for a propulsion battery pack providing power to the vehicle's electric machine and on which the driver's seat is generally intended to rest fixedly.

[0008] Such a box is classically formed of a tubular metal frame covered by an outer envelope of thin sheet metal covering, this frame comprising an upper frame supported in particular by two uprights extending fixedly between the intermediate cross member of reinforcement of the base and the front edge of this upper frame.

[0009] In the event of a violent frontal impact with an obstacle such as a wall or another vehicle, the front wheel, acting as a rigid point, is driven rearward and strikes the central portion of the front crossmember of the underbody. This crossmember transmits almost all of the impact forces to the central side member of the underbody, the front end of which first deforms elastically and then detaches by tearing, at a rupture zone located between the front crossmember and the intermediate reinforcing crossmember, from the rest of the central side member. This front end of the central side member then continues its rearward movement, coming into contact with the outer casing of the body, which it pulls along with it until it impacts the battery pack.

[0010] Such damage to the integrity of the battery pack can cause the deterioration of some of its electrochemical cells and thus generate serious consequences for the safety of the driver, in particular when they cause an explosion, a fire or an acid leak. Description of the invention

[0011] The present invention therefore aims to improve the situation.

[0012] For this purpose, it proposes a welded steel body structure for a light electric-powered tricycle-type vehicle, comprising a base including two side rails, two front and rear cross members extending fixedly between the front and rear ends of said side rails, a central side member extending fixedly between said front and rear cross members, and an intermediate reinforcing cross member extending fixedly on either side of said central side member between said side rails, said body structure also comprising a box defining a housing for a propulsion battery pack and having a chassis comprising an upper frame supported in particular by two uprights extending fixedly between said intermediate reinforcing cross member and the front edge of said upper frame, being arranged on either side of said central side member; characterized in that said box structure further comprises a protective device including a metal apron extending fixedly between said uprights of said box.

[0013] The addition of such a protective device thus makes it possible, in the event of a violent frontal impact causing the front end portion of the central longitudinal member to be torn off and its separation from the rest of this longitudinal member, to absorb the kinetic energy of this front end portion of this central longitudinal member driven backwards with the front crossmember of the underbody, so as to ensure the blocking of this front end before it reaches the battery pack.

[0014] According to preferred characteristics of said case structure according to the invention: - said protective device is fixedly mounted in a removable manner by screwing it onto said uprights; - said apron is formed by a plate of high-strength, high-yield-strength steel sheet; - said protective device further comprises several transverse hollow metal tubes, each fixed by weld beads against the front face of said plate; - said tubes are obtained by rolling and welding from a sheet of high strength and high yield strength steel; - said tubes are distributed regularly over the height of said plate according to a predetermined vertical spacing; - said spacing is between 10 and 20 millimeters; - said deck is made up of a mesh of metal strips intersecting in rows and columns; and / or - said slats are spaced less than or equal to 5 millimeters apart. The invention also aims, in a second aspect, at a light electrically powered tricycle-type vehicle comprising such a body structure. Brief description of the drawings

[0015] The description of the invention will now be continued by a detailed description of an example embodiment, given below by way of illustration but not limitation, with reference to the accompanying drawings, on which: - [Fig.1] represents a partial perspective top view of a body structure, according to a first embodiment of the invention, of a light electrically powered tricycle-type vehicle; - [Fig.2] is an enlarged perspective view from another angle of the front part of the body structure of [Fig.1]; - [Fig.3] represents a perspective view of the protection device included in the box structure of [Fig.1]; - [Fig. 4] is a view similar to [Fig. 2] of the front part of a body structure, according to a second embodiment of the invention, of a light electrically powered tricycle-type vehicle; and - [Fig.5] represents a perspective view of the protection device included in the box structure of [Fig.4]. Description of the implementation methods

[0016] Fig. 1 represents a partial view of the body structure 100 of a light electrically powered tricycle-type vehicle according to the invention.

[0017] A direct orthogonal frame XYZ is defined with respect to this vehicle, comprising three axes perpendicular in pairs, namely: - a horizontal longitudinal axis X, parallel to the ground and oriented according to the general direction of movement of the vehicle; - a horizontal transverse axis Y, also parallel to the ground and perpendicular to the X axis; and - a vertical axis Z, perpendicular to the ground as well as to the horizontal XY plane.

[0018] In the following description, and by convention, the terms "lower," "upper," "front," and "rear" shall be understood in relation to the overall orientation of the vehicle. The terms "lower" and "bottom" shall indicate a closer proximity to the ground in the vertical direction than the terms "upper" or "top." The term "front" shall indicate a forward-facing position of a vehicle in the horizontal direction, and the term "rear" shall indicate a rearward-facing position of a vehicle in the same horizontal direction.

[0019] The terms "external" and "internal" will be used to define the relative position of an element with reference to the vehicle's median vertical longitudinal plane. The element closest to this plane will thus be described as internal, as opposed to the other element further from this same plane, which will be described as external.

[0020] Furthermore, the term "substantially" will be used to indicate that a slight deviation is permitted from a predetermined nominal position or arrangement, while remaining within the scope of the invention. For example, "substantially vertical" will indicate that a deviation of approximately 20° from a strictly perpendicular orientation is permitted within the scope of the invention.

[0021] Made from metal parts assembled together by mechanical welding, the body structure 100 includes a platform or body base 110.

[0022] This base 110 comprises two side rails 111, 112, a front cross member 113 extending fixedly between the front ends of these side rails 111, 112 to which it is welded, as well as a rear cross member not visible in the figures and extending fixedly between the front ends of these side rails 111, 112 to which it is welded.

[0023] As can be seen more clearly in [Fig.2], the underframe 110 also includes a central longitudinal member 114 extending fixedly between the front cross members 113 and rear cross members to which it is welded, an intermediate reinforcing cross member 115 extending fixedly on either side of the central longitudinal member 114 between the lateral longitudinal members 111, 112 to which it is welded, as well as several intermediate reinforcing longitudinal members extending fixedly between two cross members to which they are welded, including in particular two longitudinal members 117, 118 extending between the front cross member 113 and the intermediate reinforcing cross member 115 symmetrically on either side of the central longitudinal member 114.

[0024] The body structure 100 also includes a cab sub-assembly 120 resting on the front part of the underbody 110, as well as a loading sub-assembly 140 resting on the rear part of this underbody.

[0025] The cab subassembly 120 includes two side frames 121, 122 each defining an access opening to the vehicle's passenger compartment, as well as a central strut 123 extending diagonally upwards and forwards from the central area of ​​the front crossmember 113 and the front end of the central side member 114 of the underbody 110.

[0026] This cab sub-assembly 120 also includes a steering column 124 comprising a tubular metal cylindrical sleeve welded to the top of the central strut 122 and extending along an axis forming a predetermined angle with the vertical determining the caster angle.

[0027] This steering column 124 is traversed by the steering shaft, not shown, of the front steering fork 125 of the vehicle partially visible on [Fig.1] and conventionally provided with at least one lateral suspension arm at the lower end of which a front wheel 126 is articulated for free rotation.

[0028] The rear portion of the cab sub-assembly 120 further includes a box 130, of rectangular parallelepiped shape extending over the width of the underbody 110 while being backed against the loading sub-assembly 140, and defining a housing for a propulsion battery block B ensuring the supply of the vehicle's electric machine.

[0029] This box 130, on which a seat not shown for the driver of the vehicle is intended to rest fixedly, comprises a tubular chassis including a horizontal upper frame 132 supported in particular by two uprights 133, 134 (see [Fig.2]) extending fixedly between the intermediate reinforcing cross member 115 of the base 110 and the front edge of this upper frame 132, being arranged symmetrically on either side of the central longitudinal member 114.

[0030] The box 130 also includes an outer sheet metal cover covering the front, top and side faces of this frame and of which only the top wall 135 is shown in [Fig.2].

[0031] According to the invention and with reference to this [Fig.2], the body structure 100 includes a device 150 for protecting the battery pack B in the event of a frontal impact, fixedly mounted between the two uprights 133, 134 of the box 130, preferably in a removable manner by screwing so as to facilitate, if necessary, its removal and replacement, for example to allow access to certain control elements present on the battery pack B.

[0032] Represented alone on [Fig.3], the protection device 150 comprises a rectangular apron 151 extending vertically from or near the intermediate reinforcing cross member 115 over at least the lower half height of the box 130.

[0033] This apron 151 is in this case formed by a metal sheet plate, advantageously made of a high-strength, high-yield-strength steel such as, for example, HD380LA, and having a thickness preferably between 2 and 4 millimeters,

[0034] The protective device 150 also includes several transverse hollow metal tubes 152, each fixed by weld beads against the front face of the apron 151, being distributed regularly over its height according to a vertical spacing e advantageously between 10 and 20 millimeters.

[0035] Extending transversely between the two uprights 133, 134 without being fixed to them and having an external diameter preferably between 10 and 20 millimeters, these tubes 152 are preferably obtained by rolling and welding from a high strength and high yield strength steel sheet such as for example HD380LA and whose thickness is preferably between 2 and 4 millimeters.

[0036] As can be seen in [Fig.3], the plate 151 has two lateral end portions 151A, 151B projecting laterally on either side of the tubes 152 and attached respectively by screwing against the rear faces of the two uprights 133, 134 by means of several non-visible screws passing through screw holes 153 provided in these lateral portions 151A, 151B and screwing into corresponding nuts welded or crimped on these rear faces of the uprights 133, 134.

[0037] In the event of a violent frontal impact causing the front end portion of the central longitudinal member 114 to be torn off and displaced towards the rear, the protective device 150 will absorb the kinetic energy of this front end of the central longitudinal member 114 by deforming at least some of the tubes 152 and the plate 151, so as to ensure that this front end of the central longitudinal member 114 is blocked before it reaches the battery pack B and risks damaging some of these electrochemical cells.

[0038] We will now quickly describe, with support from Figures 4 and 5, a body structure 100' of a light electrically powered tricycle-type vehicle according to a second embodiment of the invention.

[0039] In the following and in these figures, the same references have been kept for the elements identical to the first embodiment described above and a prime has been added for the similar elements.

[0040] The crate structure 100' is similar to the crate structure 100 with the notable exception of its protection device 160 which differs from the device 150.

[0041] As illustrated by [Fig.4], this protective device 160 is also fixedly mounted between the two uprights 133, 134 of the box 130, preferably in a removable manner by screwing so as to facilitate its removal and replacement.

[0042] Represented alone on [Fig.5], the protection device 160 comprises a rectangular apron 161 made up of a mesh of metal slats 162 intersected in rows and columns.

[0043] Advantageously formed from a high-strength, high-yield-strength steel sheet such as, for example, HD380LA, these slats 162 preferably have a thickness between 1.5 and 2 millimeters and are spaced apart from each other by a gap advantageously less than or equal to 5 millimeters.

[0044] In the same way as the apron 151 of the protective device 150, the apron 161 has two end lateral portions 161A, 161B attached respectively by screwing against the rear faces of the two uprights 133, 134 by means of several non-visible screws passing through these lateral portions and screwing into corresponding nuts welded or crimped on these rear faces of the uprights 133, 134.

[0045] In the event of a violent frontal impact causing the front end portion of the central longitudinal member 114 to be torn off and displaced towards the rear, the mesh apron 161 will absorb the kinetic energy of this front end of the central longitudinal member 114 by deforming at least some of its slats 162, so as to ensure the blocking of this front end of the central longitudinal member 114 before it reaches the battery pack B and risks damaging some of these electrochemical cells.

[0046] Finally, it should be noted that the invention is not limited to the particular embodiments described herein by way of example. A person skilled in the art may, depending on the applications of the invention, make various modifications and variations falling within the scope of the invention's protection.

Claims

Demands

1. Welded body structure (100; 100') for a light electrically powered tricycle-type vehicle, comprising a subframe (110) including two side members (111, 112), two front (113) and rear cross members extending fixedly between the front and rear ends of said side members (111, 112), a central side member (114) extending fixedly between said front (113) and rear cross members, and an intermediate reinforcing cross member (115) extending fixedly on either side of said central side member (114) between said side members (111, 112), said body structure (100;100') also comprising a box (130) defining a housing for a propulsion battery pack (B) and having a chassis comprising an upper frame (132) supported in particular by two uprights (133, 134) extending fixedly between said intermediate reinforcing cross member (115) and the front edge of said upper frame (132) being arranged on either side of said central longitudinal member (114); characterized in that said body structure (100; 100') further comprises a protection device (150; 160) comprising a metal apron (151; 161) extending fixedly between said uprights (133, 134) of said box (130).;

2. Carcass structure (100; 100') according to claim 1, characterized in that said protective device (150; 160) is fixedly mounted in a removable manner by screwing onto said uprights (133, 134).

3. Body structure (100) according to any one of claims 1 or 2, characterized in that said apron (151) is formed by a high-strength, high-yield-strength steel sheet plate.

4. Carriage structure (100) according to claim 3, characterized in that said protection device (150) further comprises several transverse hollow metal tubes (152) each fixed by weld beads against the front face of said plate (151).

5. Carriage structure (100) according to claim 4, characterized in that said tubes (152) are obtained by rolling and welding from a high strength and high yield strength steel sheet.

6. A body structure (100) according to any one of claims 4 or 5, characterized in that said tubes (152) are distributed in such a way regular on the height of said plate (151) according to a predetermined vertical spacing.

7. Carcass structure (100) according to claim 6, characterized in that said spacing is between 10 and 20 millimeters.

8. Car body structure (100') according to any one of claims 1 or 2, characterized in that said apron (161) is made up of a mesh of metal slats (162) intersecting in rows and columns.

9. Box structure (100') according to claim 8, characterized in that said slats (162) are spaced apart from each other by a gap less than or equal to 5 millimeters.

10. A light, electrically powered tricycle-type vehicle comprising a body structure (100; 100') according to any one of claims 1 to 9.

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