Electric vehicle with axle modules

Abstract

Electric vehicle (1) for transporting persons and / or loads, comprising a frame structure (2) and axle modules (7, 8) coupled to the frame structure (2), a front axle module (7) and a rear axle module (8), to which the wheels (9) are kinematically coupled, wherein at least one of the axle modules (7, 8) has a drive and an energy source, wherein at least one of the axle modules (7, 8) has four suspension points (11, 12) for connection to the frame structure (2) by means of elastic bearings, wherein two suspension points (11, 12) form a pair and the pairs are located at different heights in the vehicle vertical direction (Z), and that one axle module (7, 8) has a battery carrier which is arranged centrally in the axle module (7, 8), characterized in thatthat a connecting line (24) from an upper suspension point (11) to a lower suspension point (12) passes through a center of mass (22) of the battery carrier in side view.

Description

[0001] The present invention relates to an electric vehicle for the transport of persons or loads according to the features in the preamble of claim 1.

[0002] Electric vehicles are a well-established technology. They use electrical energy to power an electric motor vehicle. However, new concepts exist that differ from vehicles operated by a single driver. These vehicles are also called people movers. Their aim is to transport multiple people or goods as comfortably as possible, especially in urban areas.

[0003] A people mover is known, for example, from WO 2018 / 222375 A1.

[0004] This type of vehicle consists of a body or chassis. Axle modules are attached to the chassis. Such an electric vehicle can travel in both directions. Therefore, the classic forward and reverse directions of travel are no longer applicable.

[0005] The aim is to have the lowest possible ground clearance to facilitate easy entry and exit for multiple people in the low-floor area, and to make access easier for people with physical disabilities. Alternatively or additionally, the goal is to maximize the available interior volume, especially for transporting goods.

[0006] From DE 10 2010 043 901 A1 a generic electrically driven axle of a two-track vehicle is known.

[0007] An axle of a motor vehicle is also known from DE 10 2018 214 288 A1.

[0008] The object of the present invention is to improve the driving comfort of a generic electric motor vehicle, starting from the prior art, while maintaining a modular design.

[0009] The aforementioned problem is solved according to the invention with the features in claim 1.

[0010] Advantageous design variants are described in the dependent claims.

[0011] The electric vehicle is designed for transporting people and / or cargo and features a frame structure. A frame structure can also be called a chassis frame or cabin frame. This is a frame structure constructed from profiles in a grid-like configuration. The frame structure can then be clad externally with windows and / or side walls, as well as roof panels and an underbody. This makes it possible to manufacture the electric vehicle as cost-effectively as possible, while simultaneously ensuring a high degree of interior flexibility and, thanks to the frame's torsional rigidity, also guaranteeing high crash safety. Furthermore, the electric vehicle's own weight is particularly low. The frame can be made of steel and / or aluminum profiles.

[0012] Axle modules are coupled to the frame structure. To differentiate them, one axle module is called a front axle module and another a rear axle module. It should be noted, however, that the forward and reverse directions of travel can be essentially identical in terms of speed, steering behavior, and other kinematic properties.

[0013] The wheels are kinematically coupled to each axle module. This is preferably achieved via wishbones; in particular, a McPherson strut suspension can also be used, i.e., a lower wishbone and a McPherson strut. However, the suspension can also be achieved via double wishbones. A transverse leaf spring is particularly preferred.

[0014] At least one of the axle modules, preferably both, has a drive and an energy source. In a particularly preferred embodiment of the invention, wheel hub motors are used as the drive. A corresponding battery housing or battery pack, also referred to as a battery tray, is also used as the energy source and is centrally located in the axle module. Most preferably, the battery housing itself is an integral part of the axle module. This ensures a particularly compact and simple modular design, especially in conjunction with the wheel hub motors. The axle module only needs to be coupled to the frame structure and connected electrically and / or for cooling. Driving functionality is thus provided. The axle module can also have a crash management system, such that, for example, a cross member is preferably arranged on the axle module itself via crash boxes.

[0015] The essential feature of the invention is that at least one of the axle modules has four suspension points for connection to the frame structure by means of elastic bearings. Two suspension points form a pair. The pairs themselves are arranged at different heights in the vertical direction of the vehicle.

[0016] It is therefore possible that the elastic mounting allows for decoupling from the frame structure. This significantly improves ride comfort, particularly interior vibration and, consequently, interior noise. Furthermore, the kinematic arrangement of the suspension points at different heights relative to the vehicle's vertical axis significantly improves the connection strength while simultaneously enhancing crash safety, as well as the torsional rigidity applied under driving or braking torque, which also contributes to ride comfort.

[0017] In a particularly preferred embodiment, a frame is formed around the top of the axle module. The frame itself is designed to form and / or house a battery box. Batteries can be arranged within the battery box. The batteries can also be arranged in two, three, or more layers.

[0018] This in turn makes it possible to maximize the interior space of the electric vehicle itself, since the space required for the drive, energy source and kinematic wheel suspension is compressed and optimally arranged in a respective axle module.

[0019] The upper pair of suspension components is formed on a corresponding support structure, which is coupled to the top-encircling frame. This structure is positioned approximately at the level of the top or upper end of the axle module.

[0020] In the longitudinal direction of the motor vehicle, the second pair of suspension points is preferably arranged on the opposite side.

[0021] Preferably, the axle module has an axle subframe. The axle subframe forms the underside or is located below the axle module. The lower suspension points are then arranged on the axle subframe. In particular, these are located at the level of an underside of the axle module. In the vertical direction of the vehicle, this is located below the upper suspension points.

[0022] Surprisingly, it has been found according to the invention that a connecting line from an upper suspension point to a lower suspension point preferably intersects the wheel center. This means that, viewed from the side, i.e., in the lateral or transverse direction of the vehicle, the center of gravity of the battery carrier lies at the level of the line through the two suspension points. It has also been found that, according to the invention, improved driving characteristics and ride comfort can be achieved; in particular, vibrations are compensated for, so that natural oscillations or other unnecessary increases in driving influences are prevented.

[0023] Further advantages, features, properties, and aspects are the subject of the following description. Preferred embodiments are illustrated in schematic figures. These serve to facilitate understanding of the invention. They show: Fig. 1. A perspective view of an electric vehicle, Fig. 2 and Fig. 3 perspective views of a front axle module, Fig. 4 and Fig. 5 a side view and front view of a basic structure of a front axle module and Fig. 6 a preferred embodiment with regard to the suspension points with bearing axial direction in the vehicle vertical direction.

[0024] Fig. Figure 1 shows an electric vehicle 1 according to the invention in the form of a people or carry mover.

[0025] The diagram shows a frame structure 2, which is made of profiles. This results in a relatively large interior space 3, which can also be referred to as the passenger compartment. The vehicle 1 also has a low ground clearance 4 in the low-floor area, allowing for easy side entry and exit. The vehicle 1 itself can be configured identically in both directions. For the sake of simplicity, however, a front 5 and a rear 6 are shown. A front axle module 7 is located at the front 5 and a rear axle module 8 at the rear 6. Wheels 9 are kinematically coupled to the respective axle modules 7 and 8, allowing for suspension travel to provide a comfortable ride. A front crossmember 10 is also shown, which incorporates a crash management system to absorb crash energy in the event of a collision.

[0026] Described here as an example using the front axle module 7, but possibly also the rear axle module 8, the suspension on the frame structure 2 is achieved via four suspension points 11. Two suspension points 11 are grouped together to form a pair. In the vehicle's vertical direction Z, the upper front suspension points 11 are arranged higher than the rear suspension points 12 located below them in the vehicle's vertical direction Z. A rubber elastomer bearing is preferably arranged at each suspension point 12, via which the respective suspension point 11, 12 is coupled to the frame structure 2.

[0027] The front axle module 7 is shown in a perspective front view in Fig. 2 shown as well as in a perspective view from below in Fig. 3. The front axle module 7 has a surrounding frame 13. In this case, the frame 13 itself forms a battery carrier for accommodating batteries 14. The battery carrier is thus an integral part of the front axle module 7. Arms 15 are arranged laterally on the frame 13 in the transverse direction Y of the vehicle. An axle subframe 16 is formed on the underside. The axle subframe 16 also forms an integral part of the front axle module 7. Furthermore, a transverse leaf spring 17 is arranged. Control arms 18 are coupled to the axle subframe 16 via this leaf spring. A shock absorber strut 19 is arranged on a strut mount 20, the strut mount 20 being attached to the frame 13. Furthermore, power electronics 21, for example in the form of an on-board charger, are provided. A cooling system, for example, may also be a component of the front axle module 7 (not shown in detail). Furthermore, optional wheel hub motors are shown, which drive the wheels 9.

[0028] Fig. 4 and Fig. Figure 5 shows a schematic front view and side view of the front axle module 7. According to Fig. Figure 4 shows the center of mass 22 of the batteries 14 or the battery carrier, as well as the wheel center 23 of a wheel 9. Also shown are the upper suspension points 11 and the lower suspension points 12 located below them in the vehicle's vertical direction Z, each pair. It is also shown that an axial direction A of the bearings is oriented in the vehicle's vertical direction Z. By using rubber-metal bearings in the suspension points 11 and 12, support in the vertical direction can thus be achieved due to the axial orientation in the vehicle's vertical direction Z. At the same time, the radial stiffness of the bearings in the vehicle's longitudinal direction X and in the vehicle's transverse direction Y can be designed to achieve improved comfort when driving over obstacles.

[0029] Fig. Figure 5 shows the side view in cross-sectional area Y of the vehicle. A connecting line 24 passes through the wheel center 23 and the center of mass 22 of the battery carrier in the side view. In a projected side view, the connecting line 24 passes through one of the two points 22, 23.

[0030] The axial alignment of the suspension points 11, 12 in the vehicle vertical direction Z is also shown again in Fig. 6. Reference symbol: 1 electric vehicle 2. Framework structure 3 Interior 4 Ground clearance 5 Front 6 Back 7 Front axle module 8 Rear axle module 9 wheels 10 crossbeams 11 upper suspension points 12 lower suspension points 13 frames 14 batteries 15 Arm 16 axle subframes 17 transverse leaf spring 18 wishbones 19 shock absorber 20 strut mounts 21 Power Electronics 22 Center of mass of the battery carrier 23 Wheel center 24 connecting straight A Axial direction X Motor vehicle longitudinal direction Y Motor vehicle transverse direction Z Motor vehicle vertical direction

Claims

[1] Electric vehicle (1) for transporting persons and / or loads, comprising a frame structure (2) and axle modules (7, 8) coupled to the frame structure (2), a front axle module (7) and a rear axle module (8), to which the wheels (9) are kinematically coupled, wherein at least one of the axle modules (7, 8) has a drive and an energy source, wherein at least one of the axle modules (7, 8) has four suspension points (11, 12) for connection to the frame structure (2) by means of elastic bearings, wherein two suspension points (11, 12) form a pair and the pairs are located at different heights in the vehicle vertical direction (Z), and that one axle module (7, 8) has a battery carrier which is arranged centrally in the axle module (7, 8), characterized by, that a connecting line (24) from an upper suspension point (11) to a lower suspension point (12) passes through a center of mass (22) of the battery carrier in side view. [2] Electric vehicle (1) according to claim 1, characterized by , that the battery carrier is arranged as an integral component in the axle module (7, 8). [3] Electric vehicle (1) according to claim 1 or 2, characterized by , that a top-circulating frame (13) is formed on the axle module (7, 8), wherein two upper suspension points (11) are arranged laterally from the frame (13). [4] Electric vehicle (1) according to any of the aforementioned claims, characterized by , that an axle subframe (16) is arranged in the lower area of ​​the axle module (7, 8). [5] Electric vehicle (1) according to claim 4, characterized by that two lower suspension points (12) are arranged on the axle subframe (16). [6] Electric vehicle (1) according to any one of claims 1 to 5, characterized by , that the lower suspension points (12) are arranged in the longitudinal direction (X) of the motor vehicle on a side of the axle module (7, 8) opposite the upper suspension points (11). [7] Electric vehicle (1) according to any one of claims 1 to 6, characterized by , that a connecting line (24) from an upper suspension point (11) to a lower suspension point (12) in side view passes through the wheel center (23) or is offset ± 100 mm at the wheel center (23) in the motor vehicle vertical direction (Z) to the wheel center (23). [8] Electric vehicle (1) according to any one of claims 1 to 7, characterized by , that the axle module (7, 8) has wheel hub motors and / or a transverse leaf spring (17). [9] Electric vehicle (1) according to any one of claims 1 to 8, characterized by , that the axle module (7, 8) has a cooling structure for the battery carrier. [10] Electric vehicle (1) according to any one of claims 1 to 9, characterized by , that the frame structure (2) is made of profiles. [11] Electric vehicle (1) according to any one of claims 1 to 10, characterized by , that an axial direction (A) of the bearings in the upper suspension points (11) and / or lower suspension points (12) is oriented in the vehicle vertical direction (Z).

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