REAR-END IMPACT FORCE DISTRIBUTION STRUCTURE FOR AN ELECTRIC-DRAWN TRUCK

Abstract

A structure (ST) is part of a three-wheeled vehicle (TM) with an electric drive unit and a rechargeable battery. It comprises two lower longitudinal members (LI), right and left, curved and coupled at the front (PVS) by lower cross members supporting the battery just before a rear (PRS), and two upper longitudinal members (LS), right and left, extending throughout this rear (PRS) and coupled to the lower longitudinal members (LI) by support members (PSL1-PSL2). Each of these upper longitudinal members (LS) includes at least one upward or downward corrugation (OV) framed by two straight sub-sections (SPR) such that, in the event of a rear-end impact, the OV and SPR transmit the vertical and longitudinal components of this force, respectively, in order to distribute the impact energy vertically and longitudinally. Figure 2

Description

Title of the invention: Force-distributed structure in case of rear-end collision, for a three-wheeled vehicle with an electric drive Technical field of the invention

[0001] The invention relates to three-wheeled vehicles with an electric drive unit and comprising one front wheel and two rear wheels, and more specifically to the structure of such three-wheeled vehicles. Prior art

[0002] Certain three-wheeled cargo bikes (or "cargo motorcycles") with an electric drive unit comprise one front wheel and two rear wheels, and a structure having, on the one hand, two lower side members, right and left, coupled at the front by lower cross members supporting a rechargeable battery associated with their electric drive unit just before a rear section, and having a curved shape in the latter, and, on the other hand, two upper side members, right and left, extending throughout this rear section and being coupled to the lower side members by support pieces. It will be understood that the lower side members are installed at a lower vertical level than the upper side members and that their curved shape allows them to come into contact with the rear sections of the upper side members. It should be noted that this type of three-wheeled cargo bike has a shape that is generally described as delta-shaped.

[0003] Generally, the distance along the transverse direction separating the upper stringers is substantially the same as that separating the lower stringers, and the possible rear floor, supported by the upper stringers, is wider than the front floor supported by the lower stringers and lower cross members.

[0004] When the three-wheeled vehicle is struck from behind at the rear ends of its upper frame members, these members absorb a significant force, primarily longitudinal in nature. There is then a high probability that the structure will deform, at least by bending its upper frame members, displacing the front upper crossmember and / or the front end of any rear floor towards the driver's seat and / or the battery, and causing the rear wall of any cab of the three-wheeled vehicle to dent (or break). This can injure the driver and / or damage the battery, which may then leak and / or cease to function and / or overheat internally, or even catch fire.

[0005] It would be possible to strengthen the protection of the driver and the battery by permanently installing a dedicated protective panel (or by significantly reinforcing the rear wall of the cab) in a vertical and transverse plane behind the seat of the driver and battery (at the interface between the front and rear parts of the structure). But this would lead to an increase not only in the cost of the tricycle, but also in its weight and therefore its electrical energy consumption (which would result in a reduction of its range in kilometers).

[0006] The invention therefore aims in particular to improve the situation, in particular to increase the passive protection of the battery and the driver in the event of a rear impact suffered by the three-wheeled vehicle. Presentation of the invention

[0007] In particular, it proposes for this purpose a structure, on the one hand, intended to be part of a three-wheeled vehicle with an electric drive unit associated with a rechargeable battery, and, on the other hand, comprising two lower longitudinal members, right and left, curvilinear and coupled in a front part by lower cross members suitable for supporting this battery just before a rear part, and two upper longitudinal members, right and left, extending throughout this rear part by being coupled to the lower longitudinal members by support pieces.

[0008] This structure is characterized by the fact that its upper longitudinal members each include at least one upward or downward undulation framed by two straight sub-parts so that in the event of absorbing a force resulting from a shock from the rear, the former and the latter transmit respectively vertical and longitudinal components of this force so as to distribute vertically and longitudinally an energy of the shock.

[0009] Thanks to the invention, the force transmitted forward by the straight sub-parts is significantly less than the large force absorbed (having mainly a longitudinal component) due to the distribution into vertical and longitudinal components, and therefore the probability that the upper front cross member and / or the front end of a possible rear floor will hit the driver's seat and / or the battery is greatly reduced, which makes it possible to increase the passive protection of the driver and the battery.

[0010] The structure according to the invention may include other features which may be taken separately or in combination, and in particular:

[0011] - its upper longitudinal members may each comprise at least two corrugations up or down;

[0012] - the undulations can be defined in positions of the upper stringers which are identical along the longitudinal direction (of the tricycle);

[0013] - the undulations can all have the same upward orientation or downwards the bottom;

[0014] - Alternatively, and in the presence of the first two options, the successive undulations each upper spar can have different orientations respectively upwards and downwards or downwards and upwards;

[0015] - it may include a floor supported by the upper stringers;

[0016] - in the presence of the last option, the upward undulations may be characteristic of transmit to the floor the vertical components of the absorbed force;

[0017] - its upper longitudinal members can be monobloc or can be made by assembly, by welding, of corrugation(s) and straight sub-parts.

[0018] The invention also proposes a three-wheeled vehicle comprising, on the one hand, an electric drive machine associated with a rechargeable battery, and, on the other hand, a structure of the type presented above and on which these electric drive machines and batteries are fixedly installed. Brief description of the figures

[0019] Other features and advantages of the invention will become apparent from an examination of the detailed description below, and the accompanying drawings (obtained using CAD / CAM (“Computer-Aided Design / Computer-Aided Manufacturing”)), in which:

[0020] [Fig-1] schematically illustrates, in a perspective view, part of a example of a three-wheeled vehicle with an electric motor and including an example of an embodiment of a structure according to the invention, without a floor, and

[0021] [Fig.2] schematically illustrates, in a left-side view, the three-wheeled vehicle with electric motive machine of the [Fig.l] with a floor. Detailed description of the invention

[0022] The invention aims in particular to provide an ST structure with force distribution in case of rear impact, and intended to be part of a TM three-wheeled vehicle with an electric drive machine and delta shape (one front wheel and two rear wheels).

[0023] In what follows, the TM tricycle (with an electric drive unit) is considered, by way of non-limiting example, to be dedicated to the transport of goods. However, the invention is not limited to this type of tricycle with an electric drive unit. It relates, in fact, to any tricycle with an electric drive unit comprising a structure with two lower, curved side members coupled at the front by lower cross members designed to support a rechargeable battery associated with its electric drive unit just before a rear section, and two upper side members extending throughout this rear section and coupled to the lower side members by support pieces. Thus, the invention also relates to tricycles with an electric drive unit dedicated to the transport of passengers.

[0024] In Figures 1 and 2, the X direction is the longitudinal direction of the TM tricycle, which is substantially parallel to the lateral (or longitudinal) sides, the Y direction is the transverse direction of the TM tricycle, which is perpendicular to the longitudinal direction X, and the Z direction is the vertical direction of the TM tricycle, which is perpendicular to the longitudinal direction X and the transverse direction Y.

[0025] Furthermore, in the preceding and following text, the term "front" is defined with respect to the front end of the TM tricycle, and the term "rear" is defined with respect to the rear end of the TM tricycle (opposite the front end). Consequently, the front part of an element is (intended to be) oriented towards the front end of the TM tricycle, while the rear part of that element is (intended to be) oriented towards the rear end of the TM tricycle.

[0026] Figures 1 and 2 schematically illustrate part of an example of a TM tricycle with a delta shape (one front wheel and two rear wheels), with an electric drive machine associated with a rechargeable BR battery, and comprising an example of an embodiment of an ST structure according to the invention.

[0027] Although only partially shown in Figures 1 and 2, the ST structure includes, in particular, two lower longitudinal members LI, right and left, lower cross members TI, and upper longitudinal members LS. This ST structure can be subdivided into a front section PVS and a rear section PRS, which extend mutually via the lower longitudinal members LI. The front section PVS includes a ZSB area in which, in particular, the driver's seat SC and the rechargeable battery BR are installed (here, under this driver's seat SC). It should be noted that this front section PVS can support a cab that is at least partially enclosed, comprising a rear wall PR at the interface with the rear section PRS and housing the battery BR and the driver's seat SC (as partially and non-limitingly illustrated in [Fig. 2]).Note that in figures 1 and 2 the cabin is essentially represented by its CC frame, but it generally includes walls, a possible windscreen and one (or two) possible door(s).

[0028] The two lower longitudinal members LI each comprise front sections PVL coupled to the front section PVS of the ST structure by lower cross members TI designed to support the battery BR (and the driver's seat SC) just before the rear section PRS of the ST structure. Furthermore, and preferably, each lower longitudinal member LI comprises, in the rear section PRS, a first front sub-section SPVL extending rearward from its front PVL section, positioned at a first vertical level (along the vertical direction Z) and extended rearward from the three-wheeled vehicle TM by a first rear sub-section SPRL positioned at a second vertical level (along the vertical direction Z) higher than the first level. In other words, in the rear section PRS, each lower longitudinal member LI has a curvilinear (upward) shape.

[0029] The two upper longerons LS extend (longitudinally) throughout the entire rear portion PRS of the ST structure, being coupled to the lower longerons LI by support members PSLm. It should be noted that in the illustrated example (which is not exhaustive) In Figures 1 and 2, each upper longitudinal member LS is coupled in the rear section PRS to the corresponding lower longitudinal member LI (and more precisely to its first front sub-section SPVL) by first PSL1 (m = 1) and second PSL2 (m = 2) support members (for example, metal profiles extending substantially vertically (along the vertical Z direction)), the second support member PSL2 being located downstream of the first support member PSL1 (relative to the front end of the tricycle TM). However, the number of support members PSLm ensuring the coupling of an upper longitudinal member LS to the corresponding lower longitudinal member LI (in the rear section PRS) can take any value greater than or equal to one.

[0030] Furthermore, and as illustrated in Figures 1 and 2, since the lower side members LI have an upward curvilinear shape, each upper side member LS comprises a second rear sub-section positioned directly above and in contact with a portion of the first rear sub-section SPRL of the corresponding lower side member LI (and thus coupled to the latter (SPRL)), and a second front sub-section extending this second rear sub-section towards the front of the three-wheeled vehicle TM (being positioned at the same vertical level) and vertically spaced (along the vertical direction Z, being positioned above) from the first front sub-section SPVL of the corresponding lower side member LI. Thus, the first rear sub-sections SPRL (curvilinear) respectively support the second rear sub-sections of the corresponding upper side members LS, and the second rear sub-sections are fixedly attached, by welding and / or screwing, to the first rear sub-sections SPRL.

[0031] These upper longitudinal members LS are coupled together by upper cross members TS and in particular front and rear upper cross members.

[0032] For example, and as partially and non-limitingly illustrated in [Fig. 2], the structure ST may comprise a floor PS supported by the upper stringers LS. It should be noted that in the illustrated example, only the frame of the floor PS is shown (the substantially flat platform of the floor PS which is attached to the frame and which supports objects (or goods) is not shown).

[0033] According to the invention, the upper side members LS each comprise at least one upward or downward corrugation OV, framed by two straight sub-parts SPR. This arrangement is intended, in the event of absorbing a force Fl resulting from a rear impact, to cause the transmission of the vertical component (F2) of this force Fl by the corrugation(s) OV and the transmission of the longitudinal component (F3) of this force Fl by the straight sub-parts SPR, in order to distribute the energy of the impact vertically and longitudinally.

[0034] Herein, "rear impact" means an impact sustained by the rear ends of the upper longitudinal members LS and lower longitudinal members LI and / or the possible floor PS along a direction having a non-zero longitudinal component (along the longitudinal direction X).

[0035] Furthermore, here we mean by "oval" a sub-part of an upper spar LS which has a rounded (or curved) curvilinear shape in an XZ (longitudinal and vertical) plane.

[0036] Thanks to this distribution of the impact energy from the rear along the vertical Z and longitudinal X directions, the force F3 transmitted forward by the straight sub-sections SPR is significantly lower than the substantial force Fl absorbed (which has primarily a longitudinal component). Consequently, the probability of the front upper crossmember TS and / or the front end of the rear floor PS striking the driver's seat SC and / or the battery BR is virtually nil, and therefore the risk of injury to the driver and / or damage to the battery BR is also virtually nil. The invention thus makes it possible to increase the passive protection of the driver and the battery BR, without increasing the weight of the three-wheeled vehicle TM, thereby avoiding a reduction in its driving range.

[0037] It should be noted that the upper spars LS can be monolithic (and therefore their shape can result from molding or bending, for example). But in an alternative embodiment, the upper spars LS can be made by assembling, by welding, corrugation(s) OV and straight sub-parts SPR.

[0038] For example, and as illustrated non-limitingly in Figures 1 and 2, each of the upper spars LS may include at least two upward or downward undulations OV, associated with at least three straight sub-parts SPR.

[0039] It should be noted that in the example illustrated, but not limited to, in Figures 1 and 2, the number of undulations OV is equal to three, and therefore the number of straight sub-parts SPR is equal to four. However, the number of undulations OV can take any value greater than or equal to one, and the number of straight sub-parts SPR can take any value greater than or equal to two.

[0040] Also, for example, and as illustrated non-limitingly in [Fig. 1], the OV undulations can be defined in identical positions of the upper spars LS (in pairs) along the longitudinal direction X. In other words, if one upper spar LS has an OV undulation in a first longitudinal position, then the other upper spar LS also has an OV undulation in that same first longitudinal position. The same applies to the longitudinal positions of the straight sub-parts SPR framing each OV undulation. This optimizes the transmission of the vertical component F2 of the absorbed force.

[0041] Also, for example, and as illustrated non-limitingly in Figures 1 and 2, the OV undulations can all have the same upward orientation or downwards. Note that in the example illustrated (but not limited to) in Figures 1 and 2, the OV undulations all have the same upward orientation. However, in an alternative embodiment not shown, the OV undulations could all have the same downward orientation.

[0042] In another embodiment not illustrated, and concerning the case where each upper spar LS comprises several corrugations OV, the successive corrugations OV of each upper spar LS may have different orientations, respectively upwards and downwards, or downwards and upwards. It will be understood that in this embodiment, if an OV corrugation of an upper spar LS is oriented upwards (respectively downwards), then the next OV corrugation of the same upper spar LS is oriented downwards (respectively upwards), and so on alternately (up / down / up / down ..., or down / up / down / up...).

[0043] Also, for example, and as illustrated non-limitingly in [Fig.2], when the structure ST includes a floor PS supported by the upper stringers LS, the upward undulations OV are suitable for transmitting to this floor PS the vertical components F2 of the absorbed force FL. This allows the floor PS to participate in absorbing part of the shock energy and thus to limit the deformations of the upper stringers LS towards the front part PVS of the structure ST (and more precisely towards the ZSB zone).

Claims

Demands

1. Structure (ST) suitable for forming part of a three-wheeled vehicle (TM) with an electric power unit associated with a rechargeable battery (BR), and comprising i) two lower longitudinal members (LI), right and left, curvilinear and coupled in a front part (PVS) by lower cross members (TI) suitable for supporting said battery (BR) just before a rear part (PRS), and ii) two upper longitudinal members (LS), right and left, extending throughout said rear part (PRS) being coupled to said lower longitudinal members (LI) by support pieces (PSLm),characterized in that said upper longitudinal members (LS) each comprise at least one upward or downward corrugation (OV) framed by two straight sub-parts (SPR) such that, in the event of absorbing a force resulting from a rear impact, the first (OV) and the latter (SPR) transmit respectively vertical and longitudinal components of this force so as to distribute vertically and longitudinally the energy of said impact.

2. Structure according to claim 1, characterized in that said upper stringers (LS) each comprise at least two upward or downward undulations (OV).

3. Structure according to claim 1 or 2, characterized in that said undulations (OV) are defined in identical positions of the upper stringers (LS) along said longitudinal direction.

4. Structure according to any one of claims 1 to 3, characterized in that said undulations (OV) all have the same upward or downward orientation.

5. Structure according to the combination of claims 2 and 3, characterized in that said successive undulations (OV) of each upper spar (LS) have different orientations respectively upwards and downwards or downwards and upwards.

6. Structure according to any one of claims 1 to 5, characterized in that it comprises a floor (PS) supported by said upper stringers (LS).

7. Structure according to claim 4 or 5 taken in combination with claim 6, characterized in that said upward undulations (OV) are suitable for transmitting said floor (PS) said vertical components of said absorbed force.

8. Structure according to any one of claims 1 to 7, characterized in that said upper stringers (LS) are monobloc.

9. Structure according to any one of claims 1 to 7, characterized in that said upper stringers (LS) are made by welding together corrugation(s) (OV) and straight sub-parts (SPR).

10. Triporteur (TM) comprising an electric drive unit associated with a rechargeable battery (BR), characterized in that it further comprises a structure (ST) according to any one of the preceding claims on which said electric drive unit and battery (BR) are fixedly installed.

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