Leaf spring device and leaf spring and damper assembly

Abstract

A leaf spring arrangement (1) for a motor vehicle is disclosed, comprising a leaf spring unit (2) made of a fiber-reinforced composite and a piezoelectric element arrangement (11, 17, 20, 25, 28, 34, 35) attached to the leaf spring unit (2), wherein the piezoelectric element arrangement (11, 17, 20, 25, 28, 34, 35) is designed to generate a voltage depending on a deformation of the leaf spring unit (2).

Description

Technical Field

[0001] The present invention relates to leaf spring devices for motor vehicles and leaf spring and damper assemblies including such leaf spring devices. Background Technology

[0002] Active suspension systems for motor vehicles may include actively controlled dampers, and, where applicable, actively controlled air springs. In such vehicles, the damping can be adjusted according to a predetermined driving mode (e.g., comfort, normal, dynamic), thereby affecting driving performance. The same applies to air springs. Determining dynamic loads with this type of system is either impossible or only possible within limited limits. This also means that driving conditions cannot be intervened in a load-sensitive manner.

[0003] The applicant is aware of existing sensor-based technologies that are additionally placed on existing chassis components to detect changes in load. These sensors are typically powered by an external power source and require physical connection to the vehicle. The sensors require voltage and signal transmission. The additional components require additional mounting space and typically provide only one input parameter to the chassis control system. The additional components add weight, especially unloaded mass, which may adversely affect ride comfort and safety. Furthermore, the additional components and their connection to existing chassis components are cost-intensive and error-prone. Summary of the Invention

[0004] With this in mind, one object of the present invention is to provide an improved leaf spring device.

[0005] Therefore, a leaf spring device for motor vehicles is proposed. The leaf spring device includes a leaf spring unit made of fiber composite plastic and a piezoelectric element configuration group attached to the leaf spring unit, wherein the piezoelectric element configuration group is configured to generate a voltage in response to deformation of the leaf spring unit.

[0006] Because the piezoelectric element assembly is located on the leaf spring unit, the load or deformation of the leaf spring assembly can be detected directly and in real time. This can be accomplished using the generated voltage. Therefore, the load and condition of a vehicle equipped with this leaf spring assembly can be determined, and this data can be used to influence, for example, the spring characteristic curve of the vehicle's leaf spring assembly and the damper characteristic curve of the damper. This improves ride comfort. Furthermore, in addition to determining the load on the leaf spring unit, energy recovery can also be performed simultaneously.

[0007] In this context, "leaf spring unit" should be understood as a spring or spring element constructed from multiple leaf spring elements or leaf spring segments connected to each other, and therefore preferably forming a zigzag or meandering geometry. Each leaf spring segment may have a sheet-like or plate-like geometry. However, "sheet-like" or "plate-like" does not preclude the leaf spring segment from being curved or having any three-dimensional shape. Unlike leaf spring units, cylindrical springs or disc springs have a helical continuous wire, giving the disc spring a cylindrical geometry.

[0008] The leaf spring unit is preferably a compression spring. However, the leaf spring unit can also be a tension spring. The leaf spring device differs from a leaf spring unit in that a leaf spring device includes both a leaf spring unit and a piezoelectric element configuration group. That is, the leaf spring unit and the piezoelectric element configuration group are parts of the leaf spring device. On the other hand, the piezoelectric element configuration group is not part of the leaf spring unit. However, this does not preclude the piezoelectric element configuration group from being attached to or fixed to the leaf spring unit. A leaf spring device may include multiple leaf spring units.

[0009] Fiber-reinforced plastics (FRP) can also be referred to as fiber-reinforced plastic materials. Fiber-reinforced plastics include plastic materials, particularly a plastic matrix, into which fibers, such as natural fibers, glass fibers, carbon fibers, and aramid fibers, are embedded. The plastic material can be thermosetting, such as epoxy resin. However, the plastic material can also be thermoplastic. The fibers can be continuous fibers. However, the fibers can also be short or medium length fibers, ranging from a few millimeters to a few centimeters in length. The fibers can be oriented or non-oriented in the plastic material. The spring unit can have a layered or delamination structure. For this purpose, for example, layers of fiber fabric or woven fabric can be impregnated with the plastic material. Alternatively, however, so-called prepregs (i.e., pre-impregnated fibers, fiber fabrics, or woven fabrics) can also be used to manufacture the leaf spring unit.

[0010] The fact that the piezoelectric element assembly is “attached” to the leaf spring unit, especially in the present case, means that the piezoelectric element assembly is preferably firmly connected to the leaf spring unit. For example, the piezoelectric element assembly is bonded to the leaf spring unit. However, “attachment” can also mean that the piezoelectric element assembly merely abuts or rests against the leaf spring unit. As used herein, “attachment” also includes embodiments where the piezoelectric element assembly is an integral part of the leaf spring unit. “Integral” in this embodiment can mean that the piezoelectric element assembly is at least partially surrounded by a fiber composite plastic, particularly by a plastic material or plastic matrix. The piezoelectric element assembly can also be at least partially covered by a fiber layer of the fiber composite plastic. In general, “attachment” in the broadest sense particularly means that there is contact between the leaf spring unit and the piezoelectric element assembly, thereby allowing force to be transmitted between the leaf spring unit and the piezoelectric element assembly.

[0011] In this context, "piezoelectric element" should be understood as a component that utilizes the so-called piezoelectric effect to perform mechanical movement by applying a voltage or to generate voltage when a mechanical force is applied. That is, when current is applied to a piezoelectric element configuration, the configuration can affect the leaf spring unit, for example, in a way that changes the spring stiffness or spring constant. Conversely, the voltage change at the piezoelectric element configuration can be inferred from the deformation of the leaf spring unit.

[0012] However, preferably, when the leaf spring unit deforms, the piezoelectric element configuration also elastically deforms, thereby generating a voltage due to the deformation of the leaf spring unit. The piezoelectric element configuration thus converts deformation energy into electrical energy. Any load or loading on the leaf spring unit causes its deformation, at least on a microscopic scale. Any deformation of the leaf spring unit further causes the piezoelectric element configuration to generate a voltage. Any number of piezoelectric element configurations can be provided. The leaf spring unit also deforms during acceleration, lateral acceleration, and deceleration in the direction of travel (e.g., during braking). This means that acceleration, lateral acceleration, and deceleration in the direction of travel can also be detected by means of the piezoelectric element configuration.

[0013] According to one embodiment, the piezoelectric element configuration group is attached to the end section of the leaf spring unit located at the end of the leaf spring unit.

[0014] For example, the piezoelectric element assembly is attached to the end section. However, the piezoelectric element assembly can also be attached to any other area of ​​the leaf spring unit. However, the piezoelectric element assembly does not necessarily need to be fixedly attached to the end section. Thus, the leaf spring unit can be easily replaced without replacing the piezoelectric element assembly. The piezoelectric element assembly can be fixedly connected to the support unit that receives the end section. For example, the piezoelectric element assembly is bonded to the support unit, particularly to the receiving cavity of the support unit.

[0015] According to a further embodiment, the leaf spring unit includes a first end section and a second end section, a first piezoelectric element configuration group is attached to the first end section, and a second piezoelectric element assembly is attached to the second end section.

[0016] The second piezoelectric element configuration group is optional. That is, the leaf spring unit includes at least the first piezoelectric element configuration group disposed at the first end section. The first end section can be arranged above the second end section relative to the direction of gravity. In this case, when viewed along the direction of gravity, the first piezoelectric element configuration group is positioned above the first end section. The second piezoelectric element configuration group is disposed below the second end section relative to the direction of gravity. This configuration ensures that the forces acting on the leaf spring assembly also act on the piezoelectric element configuration group.

[0017] According to a further embodiment, the leaf spring unit also includes a support unit in which an end section is received, wherein a piezoelectric element configuration group is disposed between the support unit and the end section.

[0018] Preferably, a first support unit is provided, to which a first end section is associated. Correspondingly, a second support unit is provided, to which a second end section is associated. The support unit may also be referred to as a spring support. The end section may be glued to the corresponding support unit or otherwise fixedly connected to the support unit. For example, the first support unit may be part of the frame of a motor vehicle. The second support unit may be part of the wheel axle guide of a motor vehicle. The first support unit is positioned above the second support unit relative to the direction of gravity.

[0019] According to a further embodiment, the leaf spring unit includes multiple leaf spring sections and multiple deflection sections, wherein one deflection section connects two adjacent leaf spring sections to each other.

[0020] Therefore, the leaf spring sections and deflection sections are arranged alternately. The leaf spring sections preferably have an S-shaped cross-section. The leaf spring sections are configured such that the leaf spring unit has the aforementioned Z-shaped or meandering geometry. The leaf spring sections can be integrally connected to each other by means of deflection sections, especially integrally made of a single material. "Integrally" or "one-piece" in this context means that the leaf spring sections and deflection sections form a common component, rather than being composed of different components. "Integrally made of a single material" in this context particularly means that the leaf spring sections and deflection sections are made entirely of the same material. Preferably, the deflection sections have a larger cross-sectional area than the leaf spring sections. This ensures that when the leaf spring unit is compressed, it is primarily the leaf spring sections that deform elastically, while the deflection sections do not. Alternatively, the leaf spring sections can be connected to each other by means of clamp-shaped deflection sections. In this case, the leaf spring unit is neither integrally formed nor integrally made of a single material.

[0021] According to a further embodiment, the deflection section has a higher stiffness than the leaf spring section.

[0022] In particular, the deflection section has a much higher stiffness compared to the leaf spring section. This can be achieved, for example, by increasing the cross-section in the region of the deflection section. This reliably prevents deformation of the deflection section when the leaf spring unit is compressed. Therefore, the spring effect is preferably achieved only through the leaf spring section. Thus, the deflection section is the deactivated region of the leaf spring unit, or can be called the non-active region. "Stiffness" describes the body's (in this case, the forming section's) resistance to elastic deformation.

[0023] According to a further embodiment, the piezoelectric element configuration group is attached to at least one of the deflection segments.

[0024] For example, piezoelectric element assemblies are integrated into deflection sections. Multiple such piezoelectric element configurations can be provided, each disposed on multiple deflection sections. Each deflection section can also be selectively equipped with a piezoelectric element configuration.

[0025] According to a further embodiment, the piezoelectric element configuration group is attached to the outer radius of the at least one deflection segment, and / or the piezoelectric element configuration group is attached to the inner radius of the at least one deflection segment, the inner radius being opposite to the outer radius.

[0026] The outer radius extends outward from two adjacent leaf spring sections. The inner radius is located inside the deflection section and close to two adjacent leaf spring sections. In particular, the outer radius is larger than the inner radius. For example, exactly one piezoelectric element configuration group can be set at the outer radius, exactly one piezoelectric element configuration group can be set at the inner radius, or piezoelectric element configuration groups can be set at both the outer and inner radii.

[0027] According to a further embodiment, the piezoelectric element configuration group is disposed inside at least one of the deflection segments.

[0028] In this context, "internal" means that the piezoelectric element assembly is at least partially surrounded by the material of the deflection section. In this case, the piezoelectric element assembly is integrated into the deflection section. In other words, the piezoelectric element assembly is at least partially surrounded by a fiber-reinforced plastic, particularly a plastic material or a plastic matrix of a fiber-reinforced plastic. For example, the piezoelectric element assembly is covered by an outermost or innermost layer of the fiber-reinforced plastic. In this respect, the piezoelectric element assembly can be arranged near the outer radius or the inner radius. Therefore, the piezoelectric element assembly can be laminated into the leaf spring unit, particularly into the deflection section of the leaf spring unit.

[0029] According to a further embodiment, the piezoelectric element configuration group includes a plurality of piezoelectric elements arranged in a matrix manner.

[0030] The arrangement of piezoelectric elements can also be referred to as a pad-like arrangement. Therefore, a group of piezoelectric element arrangements can also be called a piezoelectric element matrix or a piezoelectric element pad. In this context, "matrix-like" means that multiple piezoelectric elements are arranged in rows and columns side-by-side, one on top of another. The individual piezoelectric elements can be interconnected. For this purpose, materials such as plastics and rubber can be used, and the piezoelectric elements are at least partially embedded in the plastic, rubber, etc.

[0031] According to a further embodiment, the leaf spring device also includes a detection and evaluation device configured to detect and evaluate the voltage generated by the piezoelectric element configuration group to generate data describing the deformation of the leaf spring unit.

[0032] The testing and evaluation equipment is also suitable for comparing predetermined parameters with generated data, such as determining the magnitude of the load on the leaf spring unit or the extent of compression of the leaf spring unit based on the generated voltage. The testing and evaluation equipment can also be used to supply voltage to a motor vehicle, such as to the vehicle's energy storage device. In this case, recovery can occur.

[0033] According to a further embodiment, the detection and evaluation device is configured to describe the loading state and / or spring travel of the leaf spring unit.

[0034] "Loading condition" can be understood as, for example, the force acting on the leaf spring unit due to the load on a motor vehicle. "Spring travel" or "displacement" should be understood as the shortening distance of the leaf spring unit from an unloaded state to a loaded state or a spring-loaded state. "Description" should be understood as, for example, the spring travel of the leaf spring unit output by a detection and evaluation device.

[0035] According to a further embodiment, the voltage generated by the piezoelectric element configuration group is used to transmit data.

[0036] This means that the piezoelectric element configuration serves as both a sensor and a voltage supplier, eliminating the need for an additional energy source. This also means that the leaf spring assembly can operate autonomously without an external power supply.

[0037] Furthermore, a leaf spring and damper assembly, including a damper and such a leaf spring device, has been proposed. In this case, the piezoelectric element configuration group is operably connected to the damper in such a way that the damper characteristics of the damper change according to the voltage.

[0038] For example, voltage can be used to control the valve of the damper. Furthermore, voltage can be used to influence the properties of the electrorheological or magnetorheological materials included in the damper. Therefore, depending on the deformation of the leaf spring unit, the damper may become stiffer or softer. This significantly improves ride comfort.

[0039] According to one embodiment, the piezoelectric element configuration group and the damper are operably connected in such a way that the piezoelectric element configuration group and the damper cooperate autonomously.

[0040] In this context, "autonomous" means that the leaf spring and damper configuration requires neither an external energy supply nor signals or data from the central vehicle control system to influence the damper characteristic curve. This significantly reduces the amount of wiring required.

[0041] As used herein, “one” should not be construed as being limited to exactly one element. Rather, multiple elements may be provided, such as two, three, or more. Similarly, any other numerals used herein should not be construed as limiting the number of elements to exactly that number. Rather, unless otherwise indicated, variations in the number are possible.

[0042] Further possible embodiments of the leaf spring device and / or leaf spring and damper configuration include combinations of features or embodiments not explicitly mentioned above or below. In this regard, those skilled in the art will also add aspects as improvements or additions to the corresponding basic form of the leaf spring device and / or leaf spring and damper configuration.

[0043] Further advantageous embodiments and aspects of the leaf spring assembly and / or leaf spring and damper configuration are the subject of the dependent claims and embodiments of the leaf spring assembly and / or leaf spring and damper configuration described below. Furthermore, the leaf spring assembly and / or leaf spring and damper configuration will be explained in more detail with reference to the accompanying drawings and preferred embodiments. Attached Figure Description

[0044] Figure 1 A schematic diagram of an embodiment of the leaf spring device is shown;

[0045] Figure 2 It shows that according to Figure 1 Another schematic diagram of the leaf spring device;

[0046] Figure 3 It shows that according to Figure 1 Detailed view III;

[0047] Figure 4 It shows that according to Figure 1 Detailed view IV;

[0048] Figure 5 It shows that according to Figure 1 Detailed view V;

[0049] Figure 6 It was shown again according to Figure 1 Detailed view V;

[0050] Figure 7 It was shown again according to Figure 1 Detailed view V; and

[0051] Figure 8 It shows that according to Figure 3 A cross-sectional view of the leaf spring assembly along section line IIX-IIX.

[0052] In the accompanying drawings, unless otherwise indicated, the same or functionally equivalent elements are given the same reference numerals. Detailed Implementation

[0053] Figure 1 A schematic diagram of leaf spring device 1 is shown. Leaf spring device 1 is suitable for motor vehicles, especially wheeled vehicles. Leaf spring device 1 can be used in the area of ​​the wheel suspension of a motor vehicle.

[0054] The leaf spring device 1 includes leaf spring units 2, which are made of fiber-reinforced plastic material or fiber-reinforced composite plastic (FRP). The leaf spring device 1 may include multiple leaf spring units 2. Fiber-reinforced plastics include plastic materials, especially plastic matrices, in which fibers, such as natural fibers, glass fibers, carbon fibers, aramid fibers, etc., are embedded. The plastic material can be thermosetting, such as epoxy resin. However, the plastic material can also be thermoplastic. The fibers can be continuous fibers. However, the fibers can also be short or medium length fibers, which can have a fiber length of a few millimeters to a few centimeters.

[0055] Leaf spring unit 2 has a meandering geometry. Leaf spring unit 2 has multiple leaf spring segments 3, which connect to each other at deflection segment 4. The number of leaf spring segments 3 is arbitrary. Figure 1 In the figure, only one leaf spring section 3 and one deflection section 4 are marked with reference numerals. In the side view, each leaf spring section 3 has an S-shaped geometry or an S-shaped orientation.

[0056] The leaf spring section 3 and the deflection section 4 are designed such that when the leaf spring unit 2 is loaded, no deformation or at least no perceptible deformation occurs in the deflection section 4. On the other hand, the leaf spring sections 3 all deform in the central region 5 and generate a spring force to counteract the load from the outside.

[0057] The first end section 6 of the leaf spring unit 2 is supported in the first support unit 7. The second end section 8 of the leaf spring unit 2 is correspondingly supported in the second support unit 9. The first support unit 7 may be, for example, part of the frame of a motor vehicle. The second support unit 9 may be part of the wheel axle guide of a motor vehicle. Support units 7 and 9 are parts of the leaf spring assembly 1. The first support unit 7 is positioned above the second support unit 9 relative to the direction of gravity g. Support units 7 and 9 are spring supports or may be referred to as spring supports.

[0058] Figure 1 The leaf spring device 1 is shown in an unloaded or inelastically functioning state. Conversely, Figure 2 The leaf spring assembly 1 in a compressed state is shown. The leaf spring section 3, which is S-shaped in the unloaded state, has a flat shape in the compressed state.

[0059] Figure 3 It shows that according to Figure 1 Detailed view III. From Figure 3 It can be seen that the first support unit 7 can be configured to receive the first end section 6 of the leaf spring unit 2 therein. For this purpose, the first support unit 7 may include a receiving cavity 10. For example, the first end section 6 is glued into the receiving cavity 10. However, the connection between the first end section 6 and the first support unit 7 can be achieved in any other way.

[0060] When viewed along the direction of gravity g, the piezoelectric element arrangement 11 is positioned above the first end section 6. The piezoelectric element arrangement 11 includes a plurality of piezoelectric elements 12 arranged in a matrix or pad-like manner. Therefore, the piezoelectric element arrangement 11 can also be referred to as a piezoelectric element pad. In this context, "piezoelectric element" should be understood as a component that utilizes the so-called piezoelectric effect to perform mechanical movement by applying a voltage or to generate a voltage when a mechanical force is applied.

[0061] The piezoelectric element assembly 11 is part of the leaf spring device 1. The piezoelectric element assembly 11 is positioned between the first end section 6 and the first support unit 7, such that the force F acting on the leaf spring unit 2 also acts on the piezoelectric element assembly 11. Preferably, the piezoelectric element assembly 11 is integrated into the receiving cavity 10. This allows for replacement of the leaf spring unit 2 without disassembling the piezoelectric element assembly 11. However, the piezoelectric element assembly 11 can also be fixedly connected to the end section 6.

[0062] The piezoelectric element configuration group 11 is equipped with a testing and evaluation device 13, which is connected to the piezoelectric element configuration group 11 via wires 14 and 15. The testing and evaluation device 13 is suitable for testing and evaluating the voltage generated by the piezoelectric element configuration group 11.

[0063] Figure 4 It shows that according to Figure 1 Detailed view IV. From Figure 4 It can be seen that the second support unit 9 can be configured to receive the second end segment 8 of the leaf spring unit 2 therein. For this purpose, the second support unit 9 may include a receiving cavity 16. For example, the second end segment 8 is glued into the receiving cavity 16. However, the connection between the second end segment 8 and the second support unit 9 can be achieved in any other way. In other words, the second support unit 9 is constructed similarly to the first support unit 7.

[0064] The second support unit 9 may have an optional associated piezoelectric element configuration group 17, which is structurally identical to the piezoelectric element configuration group 11. The leaf spring device 1 may include only the piezoelectric element configuration group 11, only the piezoelectric element configuration group 17, or both. Like the piezoelectric element configuration group 11, the piezoelectric element configuration group 17 includes a plurality of piezoelectric elements 12 arranged in a matrix or pad-like manner. Therefore, the piezoelectric element configuration group 17 may also be referred to as a piezoelectric element pad. Preferably, the piezoelectric element configuration group 17 is incorporated into the receiving cavity 16. This allows the leaf spring unit 2 to be replaced without disassembling the piezoelectric element configuration group 17. However, the piezoelectric element configuration group 17 may also be fixedly connected to the end section 8.

[0065] When viewed along the direction of gravity g, the piezoelectric element assembly 17 is positioned below the second end section 8. The piezoelectric element assembly 17 is positioned between the second end section 8 and the second support unit 9, such that the force F acting on the leaf spring unit 2 also acts on the piezoelectric element assembly 17. The piezoelectric element assembly 17 is connected to the testing and evaluation device 13 via lines 18 and 19. Alternatively, the piezoelectric element assembly 17 may also be equipped with its own testing and evaluation device 13.

[0066] Figure 5 It shows that according to Figure 1 Detailed view V. (See example) Figure 5 As shown, the piezoelectric element assembly 20 can be mounted on one or more deflection segments 4 on the outer side. The piezoelectric element assembly 20 can be coupled to a corresponding deflection segment 4. The deflection segment 4 includes an outer radius 21 to which the piezoelectric element assembly 20 is attached and an inner radius 22 opposite to the outer radius 21. The deflection segment 4 undergoes almost no deformation. However, even slight deformation of the deflection segment is sufficient to sufficiently deform the piezoelectric element assembly 20.

[0067] However, the piezoelectric element configuration group 20 can also be attached to any other region of the leaf spring unit 2, such as to a leaf spring segment 3. The piezoelectric element configuration group 20 is constructed in a similar manner to piezoelectric element configuration groups 11, 17. That is, the piezoelectric element configuration group 20 can include a plurality of piezoelectric elements 12 arranged in a matrix or pad-like manner. The piezoelectric element configuration group 20 can be provided as an addition to or alternative to piezoelectric element configuration groups 11, 17. Lines 23, 24 can be used to connect the piezoelectric element configuration group 20 to the testing and evaluation device 13. Alternatively, the piezoelectric element configuration group 20 can have its own testing and evaluation device 13.

[0068] Figure 6 It was shown again according to Figure 1 However, a detailed view V shows a further embodiment of the leaf spring device 1. (See attached image.) Figure 6 As shown, with Figure 5 Unlike other piezoelectric element configurations, the piezoelectric element configuration group 25 can also be attached to the inner side of one or more deflection segments 4, i.e., the inner radius 22. The piezoelectric element configuration group 25 can be incorporated into the corresponding deflection segment 4, specifically the inner radius 22. However, the piezoelectric element configuration group 25 can also be attached to any other region of the leaf spring unit 2, for example, to one of the leaf spring segments 3. The piezoelectric element configuration group 25 is constructed in a similar manner to piezoelectric element configuration groups 11, 17, and 20. That is, the piezoelectric element configuration group 25 can include a plurality of piezoelectric elements 12 arranged in a matrix or pad-like manner.

[0069] Piezoelectric element configuration group 25 can be provided as an addition to or alternative to piezoelectric element configuration groups 11, 17, and 20. Piezoelectric element configuration group 25 can be connected to testing and evaluation equipment 13 via lines 26 and 27. Alternatively, piezoelectric element configuration group 25 can have its own testing and evaluation equipment 13.

[0070] Figure 7 It was shown again according to Figure 1 However, a detailed view V shows a further embodiment of the leaf spring device 1. (See attached image.) Figure 7 As shown, with Figure 5 and Figure 6 Unlike other components, the piezoelectric element configuration group 28 can be integrated into the leaf spring unit 2, and more particularly into a deflection segment of the deflection segment 4. In this context, "integration" means that the piezoelectric element configuration group 28 is at least partially surrounded by the material of the leaf spring unit 2. For example, the piezoelectric element configuration group 28 may be covered only by the outermost or innermost layer of a fiber composite plastic, of which the leaf spring unit 2 is made.

[0071] Preferably, the piezoelectric element arrangement group 28 is disposed on one or more deflection segments in the deflection segment 4. However, the piezoelectric element arrangement group 28 may also be disposed in any other region of the leaf spring unit 2, such as in one leaf spring segment of the leaf spring segment 3. The piezoelectric element arrangement group 28 is constructed in a similar manner to piezoelectric element arrangement groups 11, 17, 20, and 25. That is, the piezoelectric element arrangement group 28 may include a plurality of piezoelectric elements 12 arranged in a matrix or pad-like manner.

[0072] Piezoelectric element configuration group 28 can be provided as an addition to or alternative to piezoelectric element configuration groups 11, 17, 20, and 25. Piezoelectric element configuration group 28 can be connected to testing and evaluation equipment 13 via lines 29 and 30. Alternatively, piezoelectric element configuration group 28 can have its own testing and evaluation equipment 13.

[0073] Figure 8 It shows that according to Figure 3However, cross-sectional views IIX-IIX show a further embodiment of the leaf spring device 1. (See diagram for reference.) Figure 8 As shown, other piezoelectric element configuration groups 34, 35 may be laterally disposed on the end section 6. These piezoelectric element configuration groups may be bonded into the receiving cavity 10. The second support unit 9 may include corresponding piezoelectric element configuration groups 34, 35. Piezoelectric element configuration groups 34, 35 are optional. Advantageously, piezoelectric element configuration groups 34, 35 can be used to detect lateral acceleration. Each piezoelectric element configuration group 34, 35 includes a plurality of piezoelectric elements 12 arranged in a pad-like or matrix-like manner.

[0074] In this regard, such as Figure 8 As shown, two piezoelectric element configuration groups 34 and 35 can be provided, such that the end section 6 is disposed between the piezoelectric element configuration groups 34 and 35. However, only one piezoelectric element configuration group 34 and 35 can also be provided. The piezoelectric element configuration groups 34 and 35 can be provided as an addition to piezoelectric element configuration groups 11, 17, 20, 25, and 28.

[0075] Using lines 36 and 37, piezoelectric element configuration group 34 can be connected to testing and evaluation equipment 13. Alternatively, piezoelectric element configuration group 34 can have its own testing and evaluation equipment 13. Using lines 38 and 39, piezoelectric element configuration group 35 can be connected to testing and evaluation equipment 13. Alternatively, piezoelectric element configuration group 35 can also include its own testing and evaluation equipment 13.

[0076] The piezoelectric element assemblies 11, 17, 20, 25, and 28 can be used for energy recovery or restoration. For this purpose, piezoelectric element assembly 11 is provided at least at the first support unit 7. Alternatively, piezoelectric element assembly 17 can be provided at the second support unit 9. When the leaf spring unit 2 is compressed or when the leaf spring unit 2 moves, the piezoelectric element assemblies 11 and 17 elastically deform, thereby converting this deformation energy into electrical energy. This can be supplied to a motor vehicle equipped with such a leaf spring device 1.

[0077] In particular, the piezoelectric element assemblies 11 and 17 generate voltage or current respectively due to deformation. The piezoelectric element assemblies 11 and 17 can therefore be used as voltage or current sources. As part of the recovery process, the generated voltage or current can, for example, be supplied back to the vehicle. For example, an energy storage device, especially a battery, can be recharged. In this case, the detection and evaluation device 13 can be adapted to supply the electrical energy generated by the piezoelectric element assemblies 11 and 17 to the energy storage device. The detection and evaluation device 13 can, in particular, be or include a charger.

[0078] To increase energy harvesting, piezoelectric element configurations 20, 25, 28, or at least one of them, may be additionally provided. However, this is not mandatory. Preferably, piezoelectric element configurations 20, 25, 28 are arranged in the low-motion region of the leaf spring unit 2, i.e., the deflection section 4, in order to generate energy from small movements or deformations of the leaf spring unit 2.

[0079] The piezoelectric element configuration groups 11, 17, 20, 25, and 28 can also be used for data generation or acquisition, particularly for generating or acquiring data on the movement, deformation, and loading of the leaf spring unit 2. Again, at least one piezoelectric element configuration group 11 associated with the first support unit 7 is provided. The more piezoelectric element configuration groups 11, 17, 20, 25, and 28 provided, the better the data quality and accuracy of the motion detection for the leaf spring unit 2.

[0080] In addition to supplying the energy generated by the piezoelectric element configuration groups 11, 17, 20, 25, and 28 back to the motor vehicle, this energy can also be used for data transmission and / or for controlling the damper 31 of the motor vehicle. Figure 1 and Figure 2 In the latter case, the control of the damper 31 can be performed, for example, without being coupled to the vehicle. In other words, the piezoelectric element configuration groups 11, 17, 20, 25, 28 and the damper 31 work together autonomously. As previously stated, the leaf spring device 1 and the damper 31 together form the leaf spring and damper configuration group 32 of the vehicle 33, which is only... Figure 1 and Figure 2 The diagram is schematically shown. The leaf spring and damper configuration group 32 is preferably autonomous, that is, it operates without external power or control.

[0081] During the operation of the leaf spring device 1, for example when the vehicle 33 is in motion, information about the load on the vehicle 33 and the current load on the leaf spring unit 2 can be obtained, for example, by monitoring and comparing the voltage and current of the piezoelectric element configuration groups 11, 17, 20, 25, and 28. This information can be used, for example, to dynamically adjust the damper characteristics of the damper 31 and adapt it to the current driving conditions. Since the piezoelectric element configuration groups 11, 17, 20, 25, and 28 themselves generate voltage, data transmission can be implemented without additional wiring. This results in cost savings. Furthermore, since the required energy is supplied by the piezoelectric element configuration groups 11, 17, 20, 25, and 28, the variable characteristics of the damper 31 can be achieved without a voltage supply from the vehicle 33.

[0082] For data transmission, piezoelectric element configuration groups 11, 17, 20, 25, and 28 can be connected to a suitable device for data transmission. The detection and evaluation device 13 is such a device or may include such a device. This connection can be independent of the installation location of the piezoelectric element configuration groups 11, 17, 20, 25, and 28 and / or the number of piezoelectric element configuration groups 11, 17, 20, 25, and 28. With this connection, real-time data regarding the loading of the leaf spring device 1 can be obtained. By comparing the data of multiple leaf spring devices 1 of the vehicle 33, the load conditions of the vehicle 33 can be derived, which allows the characteristics of the damper 31 to be adjusted for comfort gains and / or driving safety gains.

[0083] Advantageously, the loading state of the vehicle 33 or the current compression stroke of the corresponding leaf spring device 1 can be determined by comparing the voltage and / or current of one or more of the piezoelectric element configuration groups 11, 17, 20, 25, 28 of one or more leaf spring devices 1 of the vehicle 33. Based on the compression stroke and / or the frequency of loading and / or the supplied voltage, the characteristic curve of the damper 31 can be adjusted in a load-sensitive and dynamic manner. The obtained electrical energy can be used for recovery and / or for data transmission.

[0084] Furthermore, the voltage generated by the piezoelectric element configuration groups 11, 17, 20, 25, 28 can also be used, for example, to change the properties of magnetorheological or electrorheological materials and thus achieve, for example, acoustic improvements by integrating the corresponding materials between the leaf spring device 1 and the vehicle 33. Advantageously, this change in the properties of the magnetorheological or electrorheological materials can also be performed without an external energy supply, and furthermore, dynamically and / or selectively. Based on the voltage or current supplied by one or more of the piezoelectric element configuration groups 11, 17, 20, 25, 28, the load on the vehicle 33 can be determined, such that, for example, in the case of overload of the vehicle 33 (the vehicle is no longer ready to move), this can be indicated to the driver via a corresponding signal.

[0085] Although the invention has been described with reference to examples of embodiments, it can be modified in many ways.

[0086] List of reference numerals

[0087] 1. Leaf Spring Device

[0088] 2 leaf spring units

[0089] 3. Leaf Spring Section

[0090] 4 Deflection Section

[0091] 5 areas

[0092] 6. End Section

[0093] 7 Support Unit

[0094] 8. End Section

[0095] 9 Support Units

[0096] 10 Reception cavity

[0097] 11 Piezoelectric Component Configuration Group

[0098] 12 Piezoelectric elements

[0099] 13. Testing and evaluation equipment

[0100] 14 lines

[0101] Line 15

[0102] 16 Reception cavity

[0103] 17 Piezoelectric Component Configuration Group

[0104] 18 lines

[0105] Line 19

[0106] 20 Piezoelectric Component Configuration Group

[0107] 21 Radius

[0108] 22 radius

[0109] Line 23

[0110] 24 lines

[0111] 25 Piezoelectric Component Configuration Group

[0112] 26 lines

[0113] Line 27

[0114] 28 Piezoelectric Component Configuration Group

[0115] Line 29

[0116] 30 lines

[0117] 31 Dampers

[0118] 32 Leaf Spring and Damper Configuration

[0119] 33 Motor vehicles

[0120] 34 Piezoelectric Component Configuration Group

[0121] 35 Piezoelectric Component Configuration Group

[0122] 36 lines

[0123] Line 37

[0124] 38 lines

[0125] Line 39

[0126] g direction of gravity

[0127] F force

Claims

1. A leaf spring device (1) for a motor vehicle (33), comprising: A leaf spring unit (2) made of fiber composite plastic, and The piezoelectric element configuration group (11, 17, 20, 25, 28, 34, 35) attached to the leaf spring unit (2) The piezoelectric element configuration group (11, 17, 20, 25, 28, 34, 35) is configured to generate voltage in response to the deformation of the leaf spring unit (2). The piezoelectric element configuration group (11, 17, 34, 35) is attached to the end section (6, 8) of the leaf spring unit (2) located at the end of the leaf spring unit (2). The support unit (7, 9) is provided in which the end sections (6, 8) are received, wherein the piezoelectric element configuration group (11, 17, 34, 35) is disposed between the support unit (7, 9) and the end sections (6, 8).

2. The leaf spring device according to claim 1, characterized in that, The leaf spring unit (2) includes a first end section (6) and a second end section (8), a first piezoelectric element configuration group (11, 34, 35) is attached to the first end section (6), and a second piezoelectric element configuration group (17, 34, 35) is attached to the second end section (8).

3. The leaf spring device according to claim 1 or 2, characterized in that, The leaf spring unit (2) includes multiple leaf spring sections (3) and multiple deflection sections (4), and a deflection section (4) connects two adjacent leaf spring sections (3) to each other.

4. The leaf spring device according to claim 3, characterized in that, The deflection section (4) has a higher stiffness than the leaf spring section (3).

5. The leaf spring device according to claim 3, characterized in that, The piezoelectric element configuration group (20, 25) is attached to at least one of the deflection segments (4).

6. The leaf spring device according to claim 5, characterized in that, The piezoelectric element configuration group (20) is attached to the outer radius (21) of the at least one deflection segment (4), and / or the piezoelectric element configuration group (25) is attached to the inner radius (22) of the at least one deflection segment (4), the inner radius (22) being opposite to the outer radius (21).

7. The leaf spring device according to claim 3, characterized in that, The piezoelectric element configuration group (28) is disposed inside at least one of the deflection sections (4).

8. The leaf spring device according to claim 1 or 2, characterized in that, The piezoelectric element configuration group (11, 17, 20, 25, 28, 34, 35) includes a plurality of piezoelectric elements (12) arranged in a matrix.

9. The leaf spring device according to claim 1 or 2, characterized in that, It has a detection and evaluation device (13) configured to detect and evaluate the voltage generated by the piezoelectric element configuration group (11, 17, 20, 25, 28, 34, 35) in order to generate data describing the deformation of the leaf spring unit (2).

10. The leaf spring device according to claim 9, characterized in that, The detection and evaluation device (13) is configured to describe the loading state and / or spring travel of the leaf spring unit (2).

11. The leaf spring device according to claim 9, characterized in that, The voltage generated by the piezoelectric element configuration group (11, 17, 20, 25, 28, 34, 35) is used for data transmission.

12. A leaf spring and damper assembly (32), comprising a damper (31) and a leaf spring device (1) according to any one of claims 1 to 11, wherein the piezoelectric element configuration group (11, 17, 20, 25, 28, 34, 35) is operably connected to the damper (31) in such a way that the damper characteristics of the damper (31) change according to voltage.

13. The leaf spring and damper assembly according to claim 12, characterized in that, The piezoelectric element configuration group (11, 17, 20, 25, 28, 34, 35) and the damper (31) are operably connected in such a way that the piezoelectric element configuration group (11, 17, 20, 25, 28, 34, 35) and the damper (31) cooperate autonomously.

Images