Haptic device

Abstract

A haptic device (100) is proposed, having a piezoelectric actuator (1) with a base body (10) and at least one amplification element (30) on a first main surface (11) of the piezoelectric actuator (1), wherein the at least one amplification element (30) has at least one fixing region (39) and a stroke region (31), the at least one amplification element (30) being fixed at the base body (10) by means of the fixing region, the stroke region being arranged spaced apart above the first main surface (11), wherein a connecting layer (20) is arranged between the at least one fixing region (39) and the first main surface (11).

Description

Technical Field

[0001] A tactile device is proposed. This device has an actuator capable of generating and / or detecting motion. For example, the tactile device can be coupled to a movable element, which may be configured as a touch-sensitive surface or the tip of a pen-like device. The actuator is, for example, a piezoelectric actuator, particularly a piezoelectric ceramic actuator. Background Technology

[0002] Haptic devices can be configured to generate haptic feedback upon touch, also known as haptic feedback. Haptic devices can be used in touchscreens, touchpads, buttons, or styluses (pen-like devices). Furthermore, haptic devices can also be used in the automotive industry.

[0003] Devices for generating tactile feedback are known from documents WO 2017 / 032 868 A1, WO 2018 / 046 201 A1, WO 2020 / 011 403 A1, and WO2021 / 019 083 A1, in which an amplifying element for amplifying the stroke is fixed at the piezoelectric actuator. The amplifying element is, for example, constructed in the form of a metal plate. Reliable fixing of the amplifying element is of particular importance here. Summary of the Invention

[0004] At least one objective of a particular implementation is to provide a tactile device.

[0005] This objective is achieved by the subject matter according to the independent claim. Advantageous embodiments and improvements of the subject matter are given in the dependent claims and further derived from the following description and drawings.

[0006] According to at least one embodiment, a tactile device is proposed. For example, the tactile device can be configured to detect tactile input. Furthermore, the tactile device can also be configured to output tactile feedback. In other words, the tactile device can, for example, be configured such that tactile signals from a user can be received through the tactile device. Furthermore, the tactile device can be configured such that tactile signals can be output to the user. In particular, the tactile device can therefore be configured to generate tactile feedback. The tactile device can therefore be configured to provide user-perceptible feedback upon a specific action or input.

[0007] The haptic device particularly preferably has a piezoelectric actuator. The piezoelectric actuator can be configured to detect tactile input and / or to output tactile feedback. The piezoelectric actuator can be based on a piezoelectric material, particularly a piezoelectric ceramic material or a piezoelectric polymer material. The piezoelectric actuator can have a substrate with a piezoelectric material. In the following, the term "piezoelectric actuator" may include both the substrate and the substrate.

[0008] Furthermore, one or more electrodes may be provided on and / or within the substrate. If no electrodes are present in the substrate, i.e., the substrate does not have internal electrodes, the piezoelectric actuator can be configured as a monolithic actuator, such as a disk or plate. For example, the piezoelectric actuator may have at least one or more internal electrodes. In this case, the substrate of the piezoelectric actuator can be constructed in a multilayer structure using multiple piezoelectric layers and internal electrodes stacked along the stacking direction.

[0009] The substrate, and thus the piezoelectric actuator, is preferably configured as a cuboid shape and has a longitudinal direction. For example, the longitudinal direction may correspond to the direction of maximum elongation of the substrate. If the substrate is constructed in a multi-layered structure, the longitudinal direction is preferably perpendicular to the stacking direction.

[0010] By applying a suitable electrical signal, a piezoelectric actuator can undergo a change in elongation in at least one direction, where such a change can be part of a tactile signal. When an alternating voltage is applied, periodic changes can be generated, thus producing vibration. In particular, the change in elongation of the piezoelectric actuator can be caused at least by the d31 effect and corresponds at least to a change in the length of the piezoelectric actuator along the longitudinal direction. Conversely, a change in elongation of the substrate in at least one direction, particularly preferably the longitudinal direction, can be caused by mechanical action induced by tactile input. This change in elongation can generate a voltage in the piezoelectric material through the inverse piezoelectric effect, which can be detected, for example, via internal electrodes.

[0011] Using piezoelectric actuators to detect and / or generate tactile signals offers significant advantages. Piezoelectric actuators have short response and decay times. Consequently, the timing and duration of detecting or generating tactile signals can be determined with great precision. Furthermore, when generating tactile signals by varying the manipulation signals applied to the piezoelectric actuator (e.g., changing the frequency, voltage, pulse sequence, and signal type), the amplitude, frequency, and duration of the piezoelectric actuator's vibration can be determined. Different manipulation signals can be used to generate different tactile signals.

[0012] According to another embodiment, the tactile device has at least one mechanical amplifying element, hereinafter simply referred to as at least one amplifying element. The at least one amplifying element is fixed at a piezoelectric actuator. In particular, the at least one amplifying element can be fixed at the piezoelectric actuator such that a change in the elongation of the piezoelectric actuator in at least one direction deforms the at least one amplifying element, thereby causing movement at least a region of the first amplifying element. Particularly preferably, the at least one amplifying element can be fixed at the piezoelectric actuator such that a change in the length of the piezoelectric actuator, and especially the substrate, at least along its longitudinal direction causes movement of a region of the at least one amplifying element in a direction perpendicular to the longitudinal direction. Furthermore, a direction having an angle greater than 0° and less than 90° with the longitudinal direction is also feasible. In other words, a region of the at least one amplifying element can move in a direction inclined relative to the longitudinal direction.

[0013] In particular, the substrate may have a first main surface and a second main surface opposite to the first main surface. The first and second main surfaces may each have a main extension direction parallel to the longitudinal direction. The orientation from the first main surface to the second main surface (which, in a multi-layered substrate, is preferably aligned with the stacking direction) is particularly preferably perpendicular to the longitudinal direction. At least one amplifying element is preferably applied to and fixed on one of the main surfaces. Without being construed as limiting, it is assumed below that, for the tactile device having only one amplifying element, this amplifying element is disposed on the first main surface of the substrate.

[0014] The substrate may also have side surfaces connecting the first and second main surfaces to each other. In particular, the substrate may have two opposing longitudinal side surfaces. Furthermore, the substrate may have two opposing end side surfaces. The longitudinal side surfaces extend along the longitudinal direction, while the end side surfaces are preferably oriented perpendicular to the longitudinal direction.

[0015] At least one amplifying element may have a first mechanical amplifying element, hereinafter simply referred to as the first amplifying element, which is applied to and fixed on a first main surface of the substrate, thereby being applied to and fixed on the first main surface of the piezoelectric actuator. Furthermore, at least one amplifying element may have at least one second mechanical amplifying element, hereinafter simply referred to as the second amplifying element, which is applied to and fixed on a second main surface of the substrate, thereby being applied to and fixed on the second main surface of the piezoelectric actuator. Therefore, the tactile device particularly preferably includes a piezoelectric actuator disposed between the first and second amplifying elements.

[0016] The following description is essentially limited to the foregoing at least one amplifying element and applies to the first amplifying element, and correspondingly also to the second amplifying element if present in a tactile device. The features and characteristics described above and below for at least one amplifying element can therefore be correspondingly applied to the first amplifying element, and also to the second amplifying element if present in a tactile device. Particularly preferably, the first amplifying element and (if present) the second amplifying element are identically configured, thereby having the same features and characteristics. If the tactile device has more than two amplifying elements, the described features and embodiments are correspondingly applicable.

[0017] At least one amplifying element may be made of metal, such as steel and / or titanium, or constructed thereof. For example, at least one amplifying element may be plate-shaped. Furthermore, at least one amplifying element may be planar, i.e., a plate formed as a plane, which is fixed to the piezoelectric actuator by means of at least one fixing region (which may be, for example, an edge region or a middle region) or also the entire surface. Particularly preferably, at least one amplifying element may be a metal arcuate member, i.e., a metal strip or plate having a non-planar geometry. For example, at least one amplifying element may be fixed to one or two end regions of the substrate along the longitudinal direction of the piezoelectric actuator, or at two end regions and one middle region, by means of at least one or preferably at least two fixing regions (which may preferably be edge regions or may be an edge region and at least one middle region along the longitudinal direction of the amplifying element). Adjacent to one fixing region or located between at least two fixing regions, there is at least one travel region spaced apart from the piezoelectric actuator. Therefore, at least one amplifying element preferably has at least one fixing region (by means of which at least one amplifying element is fixed to the substrate) and travel regions (which are spaced apart above the respective main surfaces). If at least one amplifying element has more than one fixed region, these fixed regions, as well as the corresponding fixing methods and means, are particularly preferably configured identically. The features and embodiments described below in conjunction with at least one fixed region are therefore equally applicable to all fixed regions of at least one amplifying element.

[0018] According to another embodiment, a connecting layer is provided between at least one fixed region and the first main surface. Therefore, the fixing of at least one fixed region at the substrate, and thus at the piezoelectric actuator, is particularly preferably achieved through the connecting layer. The connecting layer is particularly preferably an adhesive or an adhesive layer. Therefore, the term "connecting layer" hereinafter may also encompass the material of the connecting layer, i.e., an adhesive. At least one amplifying element can therefore preferably be fixed to the piezoelectric actuator by an adhesive connection. If the at least one amplifying element is made of titanium or is made of titanium, this has the advantage that its coefficient of thermal expansion is very similar to that of the piezoelectric actuator, resulting in only small or no mechanical stress during temperature changes, so that the adhesive connection is subjected to little or no mechanical load during temperature changes. Furthermore, the connecting layer may also be, for example, a solder layer, a weld layer, or a silver sintered layer, or have these layers.

[0019] A dielectric material may be disposed, for example, between the travel region of the at least one amplifying element and the main surface, and the at least one amplifying element is disposed and fixed on the main surface. The dielectric material may be one or more materials, selected from air, plastic film, and plastic foam.

[0020] With at least one amplifying element, as described above, the elongation change and, particularly preferably, the length change of the piezoelectric actuator can be converted into an elongation change and / or a stroke motion perpendicular or inclined to the elongation change and, preferably, the length change of the piezoelectric actuator. Conversely, elongation changes and / or stroke motions, for example, mechanically induced by the user, can be converted into elongation changes perpendicular or inclined to them, and, particularly preferably, a length change of the piezoelectric actuator, wherein, in the case of a piezoelectric actuator in a multilayered configuration, the direction of the stroke motion preferably corresponds to the stacking direction. The stroke motion can have a much larger amplitude than the length change. For example, the amplitude of the stroke motion can be 5 to 40 times the amplitude of the length change. Amplification can thus be achieved by combining the piezoelectric actuator with at least one amplifying element.

[0021] At least one amplifying element may be without a notch and have a constant wall thickness. By omitting the notch in the at least one amplifying element, the manufacture of the at least one amplifying element can be simplified. Furthermore, the at least one amplifying element may have at least one notch, which reduces the mechanical resistance to deformation of the at least one amplifying element. Especially when the amplifying element has a thickness at which deformation would require very large forces, the use of a notch in the amplifying element can be meaningful because the notch facilitates deformation. The notch can be produced, for example, by methods such as milling, stamping, and / or embossing.

[0022] According to another embodiment, the tactile device has at least one fixation improvement element, which is configured to enhance the reliability of fixation of at least one fixation region at the substrate. Particularly preferably, the at least one fixation improvement element can be configured to enhance the durability of fixation of at least one fixation region, achieved through a connecting layer, at the piezoelectric actuator. Forces, such as shear forces, may arise in the region of the connecting layer due to the deformation of the piezoelectric actuator and at least one amplifying element as described above. These forces may promote the detachment of at least one fixation region from the piezoelectric actuator. This is especially true under harsh conditions, such as increased humidity and / or increased temperature, as the connecting layer may be weakened as a result. The at least one fixation improvement element can be configured to counteract this detachment effect. The embodiments and features for the at least one fixation improvement element described below can exist individually or in combination. If the at least one amplifying element has multiple fixation regions, these fixation regions can each have one or more identical or different fixation improvement elements. Accordingly, the embodiments and features for the at least one fixation improvement element described below are equally applicable to all fixation regions of the tactile device.

[0023] According to another embodiment, at least one fixing improvement element is part of at least one amplifying element. In other words, the fixing improvement element may have a structure, or be located within or at least in the amplifying element, which is configured to, for example, counteract the aforementioned detachment effect promoted by shear force.

[0024] For example, at least one fixing improvement element may have a surface structure in at least one fixing region facing the substrate and thus the fixing surface facing the piezoelectric actuator, wherein at least a portion of the connecting layer is provided in the surface structure. The surface structure may, for example, have or have at least one recess. By having at least one recess (which may, for example, form a groove in the form of a wedge-shaped opening in the fixing surface), a local increase in the amount of material used in the connecting layer can be achieved, thereby achieving a locally larger thickness of the connecting layer. Particularly preferably, the recess may be formed at the edge of the at least one fixing region facing the travel region. A particularly high tendency to detach may exist at the edge of the fixing region facing the travel region, which can be offset by a locally larger thickness of the connecting layer. Furthermore, as a surface structure, the fixing improvement element may have a surface-enlarged structure in which at least a portion of the connecting layer is provided. The surface-enlarged structure may, for example, have grooves or recesses, such as longitudinal or transverse grooves. By having a surface-enlarged structure, the interface between the fixing surface and the connecting layer can be increased, thereby improving the fixing effect of the connecting layer.

[0025] Furthermore, at least one fixing improvement element may have at least one wing-shaped element adjacent to the fixing region, wherein the wing-shaped element extends at least partially along a side of the substrate adjacent to the first main surface, particularly preferably a longitudinal side. The wing-shaped element may be integrally formed with the fixing region and, for example, form a web or clip that covers or surrounds a portion of the side. Additionally, at least one fixing improvement element may have two wing-shaped elements that extend at least partially along two opposing side surfaces of the substrate, particularly preferably two longitudinal side surfaces. At least one wing-shaped element is particularly preferably oriented perpendicular to the fixing surface.

[0026] Additionally, the connecting layer can be disposed not only between the fixed surface and the main surface of the substrate, but also between at least one wing-shaped element and the substrate. In other words, at least one wing-shaped element can increase the interface between at least one amplifying element and the substrate. Furthermore, by disposing the wing-shaped element on the side of the substrate, support and force guidance different from those in the fixed area can be achieved, thereby counteracting the detachment effect. An improved and defined force distribution and increased stiffness of the fixed area can therefore be achieved by at least one wing-shaped element. Furthermore, as described above, the first and second amplifying elements described above are formed, wherein the connecting layer is additionally disposed between at least one wing-shaped element of at least one amplifying element and at least one wing-shaped element of the fixed area and / or another amplifying element. In other words, the two amplifying elements can be fixed to each other by the connecting layer between the respective wing-shaped elements and / or the fixed area, thereby counteracting the detachment effect. Accordingly, at least one wing-shaped element of at least one amplifying element can be fixed to the substrate and / or the fixed area and / or the wing-shaped element of the other amplifying element by means of a portion of the connecting layer. Furthermore, at least one wing-shaped element of at least one amplifying element may have a toothed structure, which is arranged and configured to engage with a complementary toothed structure of a wing-shaped element or a fixed region of another amplifying element. In this case, a connecting layer may preferably also be additionally provided between the toothed structures of the two amplifying elements. The toothed structure may, for example, be formed such that a wing-shaped element of one amplifying element, or a portion thereof, is disposed longitudinally next to a wing-shaped element of another amplifying element, or a portion thereof.

[0027] According to another embodiment, the fixed improvement element has a region with at least one amplifying element, or a region that extends beyond the base on a side opposite to the travel region. In other words, at least one amplifying element can extend beyond the base on a side opposite to the travel region. This provides protection for the end region of the piezoelectric actuator, i.e., especially edge protection, preferably along the longitudinal direction.

[0028] According to another embodiment, the fixing improved element has at least one fixing region with at least one amplifying element covered by a connecting layer. In other words, the fixing region can be covered by the material of the connecting layer. In particular, the connecting layer can form a cap over the substrate and the amplifying element in the fixing region, such that the fixing region, together with a region of the substrate, is enclosed in the connecting layer.

[0029] According to another embodiment, at least one fixing improvement element has a prepreg between the first main surface and the fixing region, and particularly the fixing surface, of at least one amplifying element, which is filled with the material of the bonding layer. The prepreg can be, in particular, a flat, planar textile semi-finished product prepregned with a thermoplastic or thermosetting matrix, having one or more unidirectional layers, said unidirectional layers having or being composed of filaments or fabrics or nonwoven fabrics having filaments preferably arranged at right angles. The prepreg can be, for example, a base material for a circuit board, and preferably has a glass fiber fabric impregnated with an epoxy adhesive. By using one or more such layers, the thickness of the bonding layer can be adjusted and thus optimized.

[0030] According to another embodiment, the fixed improvement element has an element that is additionally present to at least one amplification element. This allows for the realization that, compared to a tactile device without a fixed improvement element, no substantial changes need to be made at the at least one amplification element.

[0031] For example, at least one fixing improvement element may have a clamping device that is pushed onto at least one amplifying element and the substrate in at least one fixing region of at least one amplifying element. Particularly preferably, the clamping device is clamp-shaped, ring-shaped, or cap-shaped. In other words, the clamping device can be a clamp element, a ring element, or a cap-shaped element. The clamping device may surround at least one fixing region and a portion of the substrate of the piezoelectric actuator, thereby counteracting the tendency to detach.

[0032] According to another embodiment, the fixing improvement element has a conformal coating covering the tactile device. This conformal coating is, in particular, a coating that differs from, for example, a volumetric potting portion covering the surface of the tactile device with a substantially uniform thin layer. The function of the covered element is preferably not hindered by the conformal coating, and the original profile remains substantially unchanged. The conformal coating can have a thickness greater than or equal to 1 µm and less than or equal to 5 mm, or less than or equal to 1 mm, or less than or equal to 100 µm, and can in particular be made of a plastic material, such as silicone- or acrylate-based plastics or materials thereof. By virtue of the conformal coating, which preferably covers all exposed surface areas, or all exposed surface areas except for the external electrodes, at least one bonding layer can be protected from harmful external influences, such as moisture, which may cause degradation of at least one bonding layer, thereby leading to fixation deterioration of at least one amplification element. The conformal coating can be applied, for example, by dip coating, spraying, or brushing.

[0033] According to another embodiment, the tactile device has a side surface adjacent to a first main surface of a substrate, where at least two external electrodes for electrically contacting the tactile device are disposed. In particular, the at least two external electrodes can be disposed and configured for electrically manipulating the substrate, thereby electrically manipulating a piezoelectric actuator. The at least two external electrodes are particularly preferably the only external electrodes of the piezoelectric actuator, and are all disposed on the same longitudinal side surface. Flexible wiring elements, such as so-called flexible printed circuits (FPCs) or cables, especially multi-pole or bi-pole cables, can be connected via the at least two external electrodes on the substrate, which may have connection portions, such as soldered contacts or plugs, on the side facing away from the substrate. If the tactile device has a conformal coating as described above, this conformal coating particularly preferably covers a portion of the flexible wiring element together with the piezoelectric actuator.

[0034] According to another embodiment, the piezoelectric actuator has at least one passive region in the substrate, i.e., a region that does not participate in the length variation of the piezoelectric actuator. The at least one passive region is preferably adjacent to at least one fixed region. At least one fixed enhancement element may have a passive region or be formed therefrom. For example, the substrate may have internal electrodes, and the passive region may be a region of the substrate without any internal electrodes. Accordingly, the piezoelectric actuator may have multiple internal electrode layers in the substrate, and the fixed enhancement element may have a region of the substrate in at least one fixed region adjacent to the at least one fixed region and without internal electrode layers. By having at least one passive region adjacent to the at least one fixed region, length variation of the piezoelectric actuator in the at least one fixed region can be avoided, thereby reducing or preventing stress that may act on the connection layer.

[0035] In the tactile devices described herein, as introduced above, it is preferable to include measures that can improve the manufacturability and / or service life of the tactile devices. Particularly advantageous features and characteristics are summarized again below.

[0036] As described, external electrodes can be applied to the same longitudinal side, rather than the end side. This can reduce the manufacturing cost of the metallization portion used for the external electrodes by 50%, because the two external electrodes can be applied in one step as contact pads without rotating the substrate. Another advantage is the possibility of using flexible wiring elements such as FPCs for electrical connections. Compared to brazed metal wires, flexible wiring elements are easier to process, thinner, and lighter in mass production, and easier to handle when assembling with dedicated FPC connectors.

[0037] In addition, as described, one or more fixed improvement elements can be provided to improve the connection between the amplification element and the piezoelectric actuator, thereby increasing the resistance to detachment.

[0038] For example, at least one amplifying element can be designed such that one or more wing-shaped elements bend over the corners of the piezoelectric actuator. This is particularly advantageous when using a liquid adhesive as the material for the connecting layer. With this configuration, it is also possible to connect the two separate amplifying elements to each other via the connecting layer, i.e., preferably by adhesive bonding. This can have the advantage that a portion of the detachment force and splitting force acting on the connecting layer cancel each other out. Furthermore, the stiffness of the connecting layer can be increased compared to a flattened embodiment of the fixed region. The increased stiffness reduces the detachment force acting on the amplifying element, which may be a critical load at the inner side of the fixed region.

[0039] Furthermore, especially with designs featuring wing-shaped elements, the material for the bonding layer can be comprehensively coated around the entire component in a fixed area. This reduces the likelihood of areas with poor bonding layer coverage and results in a uniform force distribution within the bonding layer.

[0040] Furthermore, to improve the amplification element-substrate connection of the mechanism, at least one clamping device can be provided, in the form of an arcuate element, clamp, ring, or cap, preferably made of metal, such as aluminum, stainless steel, or titanium, and preferably having a function similar to that of a wing-shaped element. In addition to bonding with the piezoelectric actuator, the clamping device can be designed to press one or more amplification elements against the substrate and maintain position, for example, by friction alone, such as via a conical internal structure.

[0041] Furthermore, the mounting area of ​​the amplifying element can be modified to form grooves or recesses. This typically results in an increased amount of material used for the bonding layer and an increased amount of material in contact with the surface of the amplifying element, thereby strengthening the connection and ensuring a more uniform force distribution. To increase the amount of material used for the bonding layer in a critical area on the inner side of the mounting area, recesses with a wedge-like shape can be machined into the amplifying element. Additionally, prepreg can be applied between the substrate and the amplifying element and filled using an adhesive for the bonding layer to achieve a uniform material distribution in the mounting area.

[0042] In addition, the substrate can be designed to form passive regions in the fixed area in order to reduce the shear forces generated by the contraction and expansion of the piezoelectric actuator at these locations.

[0043] Constructions with wing-shaped elements or clamping devices also protect the piezoelectric actuator from impacts and mechanical contact, as it is fully covered by the connecting layer and the amplifying element, preferably made of metal. This protection is not limited to specific variations of the amplifying element and can be applied to any shape. Furthermore, the amplifying element can be designed to be flush with the substrate, which also protects the piezoelectric actuator from impacts or collisions.

[0044] To improve the durability of the bonding layer under harsh conditions, a conformal coating can be applied as a protective measure. This coating is specifically applied to protect the bonding layer from damage and failure. Before the coating process, the edges of the substrate can be rounded. This has the advantage of resulting in a very uniform layer thickness across the entire component. This uniformity helps ensure reliable resistance to high humidity. In addition to the rounded edges, it is advantageous to harmonize the viscosity of the coating material itself, such as the resin, with the piezoelectric actuator to further improve the wettability of the component edges. Attached Figure Description

[0045] Other advantages, advantageous implementation methods and improvements can be derived from the embodiments described below in conjunction with the accompanying drawings.

[0046] Figure 1A and Figure 1B A schematic illustration of a tactile device according to one embodiment is shown;

[0047] Figure 2A and Figure 2B A schematic illustration of a tactile device according to other embodiments is shown;

[0048] Figures 3A to 3C A schematic illustration of a tactile device according to another embodiment is shown;

[0049] Figure 4 A schematic illustration showing a portion of a tactile device according to another embodiment;

[0050] Figures 5A to 5C A schematic illustration of a tactile device according to another embodiment is shown;

[0051] Figures 6A to 6C A schematic illustration of a tactile device according to another embodiment is shown;

[0052] Figures 7A to 7G A schematic illustration of a tactile device according to other embodiments is shown;

[0053] Figure 8A and Figure 8B A schematic illustration of a tactile device according to another embodiment is shown;

[0054] Figures 9A to 9C A schematic illustration of a tactile device according to another embodiment is shown;

[0055] Figures 10A to 10C A schematic illustration of a tactile device according to another embodiment is shown;

[0056] Figures 11A to 11C A schematic illustration of a tactile device according to another embodiment is shown;

[0057] Figures 12A to 12C A schematic illustration of a tactile device according to another embodiment is shown;

[0058] Figures 13 to 15 A schematic illustration of a tactile device according to other embodiments is shown;

[0059] Figure 16A Figure 18C shows a schematic illustration of a tactile device according to another embodiment;

[0060] Figures 19A to 22B A schematic illustration of a tactile device according to other embodiments is shown.

[0061] In the embodiments and figures, identical, similar, or equivalent elements may be provided with the same reference numerals. The elements shown and their dimensional proportions relative to each other should not be considered proportional; rather, individual elements, such as layers, components, parts, and regions, may be shown exaggerated for better illustration and / or for better understanding.

[0062] The features and embodiments described in conjunction with the accompanying drawings can be combined with each other according to other embodiments, even if not all combinations are explicitly described. Furthermore, the embodiments described in conjunction with the accompanying drawings may alternatively or additionally have other features as described in the general overview section. Detailed Implementation

[0063] exist Figure 1A and Figure 1B The image shows an embodiment of a tactile device 100 having a piezoelectric actuator 1 and an amplifying element 30, in perspective and cross-sectional view. Figure 1A and Figure 1B The geometry of the piezoelectric actuator 1 and amplifying element 30 shown is to be understood purely by way of example in order to illustrate the functional principles and interaction of the piezoelectric actuator 1 and the amplifying element 30. Variations of the illustrated embodiment, such as variations in geometric design, are not excluded from the following description. Furthermore, in the illustrated embodiment and the embodiments described below, for example, only one amplifying element 30 may be present.

[0064] The piezoelectric actuator 1 has a substrate 10 having a first main surface 11 and a second main surface 12, on which one of an amplifying element 30 is disposed respectively. The substrate 10 has a stack consisting of internal electrodes 13 and piezoelectric layers 14 alternately stacked vertically in a stacking direction S, the piezoelectric layers being electrically contacted via the internal electrodes 13. The internal electrodes 13 can be electrically contacted from the outside via external electrodes 15 on the surface of the substrate 10. Although in Figure 1B The diagram shows multiple internal electrodes 13, but the substrate 10 may also have only one, two, or other numbers of internal electrodes 13. Furthermore, the substrate 10 may also be without internal electrodes, allowing it to be configured as a monolith or plate without internal electrodes. In this case, electrical contact is made solely via external electrodes 15.

[0065] The substrate 10 is preferably constructed in a cuboid shape as shown in the figure, and is elongated, having a longitudinal direction of length L, which corresponds to the main extension direction of the substrate 10. Perpendicular to the longitudinal direction, the substrate 10 has a width direction of width B. Perpendicular to the longitudinal direction, the substrate 10 terminates at an end face 16. Along the width direction, the substrate 10 terminates at a longitudinal face 17, which is oriented perpendicular to the width direction. The end face 16 and the longitudinal face 17 form the sides of the substrate 10. In a height direction perpendicular to both the longitudinal and width directions, the substrate 10 has a height H and terminates at an upper side 18 (which forms a first main surface 11) and a lower side 19 (which forms a second main surface 12), which are perpendicular to the height direction. The height direction preferably corresponds to the stacking direction S. Alternatively to the cuboid shape shown, the substrate 10 may also have other shapes, wherein preferably at least the upper side 18 and the lower side 19 are parallel to each other.

[0066] A first amplifying element 30 is disposed on the substrate 10 and thus on the first main surface 11 of the piezoelectric actuator 1, and a second amplifying element of the amplifying element 30 is disposed on the substrate 10 and thus on the second main surface 12 of the piezoelectric actuator 1 opposite to the first main surface 11 along the stacking direction S. Although two amplifying elements 30 are always shown here and below, it is also possible, for example, for only the first amplifying element 30 to be present on the first main surface 11. The amplifying element 30 has a fixing region 39 by means of which the amplifying element 30 is fixed on the respective main surfaces 11, 12.

[0067] As described above, the piezoelectric actuator 1 also has two external electrodes 15, which are arranged for external electrical contact with the substrate 10 and thus the piezoelectric actuator 1. The external electrodes 15, such as... Figure 1AAs shown, the electrode is preferably applied to one of the longitudinal side surfaces 17 of the substrate 10. The internal electrode 13 alternately contacts one of the external electrodes 15 in the stacking direction S. The external electrode 15 is preferably applied in the form of one or more metal layers by means of sputtering, screen printing, dip coating or other suitable methods. By arranging the external electrodes 15 side by side on the same longitudinal side surface 17, it is preferable to carry out the process in a common process step.

[0068] The piezoelectric layer 14 can be, for example, lead zirconate titanate ceramic (PZT ceramic). The PZT ceramic may also additionally contain Nd and Ni. Alternatively, the PZT ceramic may additionally contain Nd, K, and optionally Cu. Alternatively, the piezoelectric layer 14 may contain Pb(Zr) x Ti 1-x )O3 + y Pb(Mn 1 / 3 Nb 2 / 3 The composition of O3. Piezoelectric ceramic materials can be used as alternatives, such as piezoelectric polymers. The internal electrode 13 and the external electrode 15 are preferably made of copper or an alloy of copper.

[0069] The substrate 10 and thus the piezoelectric actuator 1 may, for example, have a length L greater than or equal to 5 mm and less than or equal to 100 mm and a width B greater than or equal to 2 mm and less than or equal to 8 mm. The height H of the piezoelectric actuator 10 may, for example, be greater than or equal to 300 μm and less than or equal to 3 mm.

[0070] The piezoelectric actuator 1 is designed such that when a voltage is applied to the external electrode 15 and thus also to the internal electrode 13, the substrate 10 deforms, particularly along the multilayer structure with the internal electrode 13 shown. Figure 1B The length change occurs in the direction R1 indicated in the diagram. Specifically, the piezoelectric layer 14 is polarized such that applying a voltage between the internal electrodes 13 causes the substrate 10 to contract, resulting in a change in the length L of the substrate 10 perpendicular to the stacking direction S. Therefore, the substrate 10 and thus the piezoelectric actuator 1 elongate transversely to the polarization direction and the electric field, also known as the d31 effect. Other elongation changes can also be achieved through other configurations with or without internal electrodes in the substrate 10. For clarity, the following description relates to the multilayer structure embodiment with the aforementioned length changes, without constituting limitation.

[0071] To direct the effect of the length variation towards the stacking direction S, an amplifying element 30 is present. When a voltage is applied to the piezoelectric actuator 1, the amplifying element 30 deforms at least partially due to the elongation of the substrate 10. Specifically, the amplifying element 30 is sized and connected to the substrate 10 of the piezoelectric actuator 1 such that the respective travel regions 31 of the amplifying element 30 are adjusted along the length L of the substrate 10 due to the change in length L. Figure 1BThe stroke movement corresponding to the stroke direction R2 of the stacking direction S is indicated in the figure, wherein the amplitude of the stroke movement can preferably be greater than the variation amplitude of the length L of the piezoelectric actuator 1.

[0072] The piezoelectric actuator 1 is preferably disposed between the amplifying elements 30 as shown. Each amplifying element 30 is preferably integral and, in the illustrated embodiment, is constructed in a strip shape with a basic rectangular shape. Furthermore, each amplifying element 30 is constructed in a curved or bent manner and is arc-shaped. Alternatively, the amplifying elements 30 may also be constructed in a flat manner. For example, the amplifying elements 30 are respectively made of or have slats thereof, especially of or have been made of steel and / or titanium.

[0073] Each amplifying element in the amplifying element 30 is preferably subdivided into multiple regions or segments. Thus, each amplifying element 30 has an edge region 32 in addition to the travel region 31, the edge region being connected to the corresponding travel region 31 via a transition region 33. These two edge regions 32 of each amplifying element 30 are placed on one of the main surfaces 11, 12 of the substrate 10. The edge region 32 is preferably inseparably connected to the corresponding main surface 11, 12, such that in the illustrated embodiment, the edge region 32 of the amplifying element 30 is a fixed region 39 of the amplifying element 30. In particular, each fixed region of the fixed region 39 is connected to the corresponding main surface 11, 12 via a connecting layer 20, the connecting layer... Figure 1B It is indicated in the text. Despite being... Figure 1A As shown in the accompanying drawings described below, the connecting layer 20 is not shown, but a connecting layer is always provided between the fixed region 39 and the piezoelectric actuator 1.

[0074] The connecting layer 20 can be particularly preferably formed by an adhesive, such as epoxy resin, so that the amplifying element 30 is preferably bonded to the substrate 10 and thus connected to the piezoelectric actuator by adhesive bonding. Alternatively, a solder layer, microsilver, or solder layer is also possible for the connecting layer 20.

[0075] The travel region 31 is spaced apart from the corresponding main surfaces 11, 12. In particular, a free region 38 is provided between the travel region 31 of each amplifying element 30 and the corresponding main surface 11. When no voltage is applied to the piezoelectric actuator 1 and no external force is applied to the amplifying element 30, the free region 38 has a height of, for example, greater than or equal to 0.1 mm and less than or equal to 5.0 mm.

[0076] Preferably, the travel region 31 is configured such that it runs substantially parallel to the orientation of the main surfaces 11, 12. The transition region 33 is inclined to the orientation of the main surfaces 11, 12. In other words, each of the transition regions 33 forms an angle with the main surfaces 11, 12. This angle is preferably less than or equal to 45°. As a result, the height of the free region 38 decreases in the direction from the travel region 31 toward the edge region 32 and thus toward the fixed region 39 of the corresponding amplifying element 30.

[0077] If a voltage is now applied to the piezoelectric actuator 1, for example by a control device connected to the external electrode 15 of the piezoelectric actuator 1, then as described above, the travel region 31 of the amplifying element 30 moves relative to the substrate 10 in the travel direction R2, which can be perceived by the user, for example, as a tactile signal. Here, the amplifying element 30 preferably bends at the transition between the travel region 31 and the transition region 33, and between the transition region 33 and the edge region 32. The movement of the edge region 32 in the travel direction R2 is prevented by means of the fixing of the connecting layer 20 to the piezoelectric actuator 1. Instead, the edge region 32 moves together with the substrate 10 in the longitudinal direction R1. Therefore, relative movement occurs between the edge region 32 and the travel region 31.

[0078] If a force is applied to the piezoelectric actuator 1 along the stroke R2, such as through tactile input from a user, the amplifying element 30 deforms such that the pressing stroke area 31 is brought closer to the corresponding main surfaces 11, 12 and the edge areas 32 are pressed apart from each other in the longitudinal direction R1. The amplifying element 30 is fixed at the base 10 of the piezoelectric actuator 1, causing the base to also deform in the longitudinal direction R1. This generates a voltage in the piezoelectric actuator 1. This voltage can be detected at the external electrode 15, and the tactile input can be inferred in this way. The piezoelectric actuator 1 can therefore be used as a sensor that can identify the force applied by the user. For this purpose, the piezoelectric actuator 1 can be connected to a control device at the external electrode 15, which evaluates the voltage generated at the piezoelectric actuator 1.

[0079] Modifications and improvements to the tactile device 100 according to the foregoing embodiments are shown in conjunction with the accompanying drawings described below. Therefore, the following description is essentially limited to the differences from the foregoing embodiments. For clarity, it may be possible that not all elements and components are shown in the accompanying drawings described below, or although shown, they may not be labeled or explained. Elements and components not shown or unlabeled in a drawing may be incorporated, for example, according to the description of the corresponding foregoing or subsequent embodiments.

[0080] like Figure 2AIn another embodiment of the tactile device 100 having a piezoelectric actuator 1 and an amplifying element 30, the amplifying element 30 may have a thinning portion 34 between the aforementioned regions, which enables better deformability of the amplifying element 30 and simplification of the aforementioned stroke movement. Furthermore, an opening 35 may be present in the stroke region 31 of the amplifying element 30, which may, for example, enable mechanical connection of the amplifying element 30 to other components, such as by riveting or threading. As shown in the following figures, the stroke region 31 may also have, for example, a connecting plate or be connected to a connecting plate, by means of which the tactile device 100 can be mounted to other components.

[0081] exist Figure 2B Another embodiment of the tactile device 100 is shown, which has a flexible wiring element 40, such as a so-called flexible printed circuit (FPC), connected to two external electrodes. For example, the wiring element 40 may be soldered to the external electrodes on the longitudinal side.

[0082] By electrically connecting the piezoelectric actuator 1 to the longitudinal side via wiring element 40, a reduction in process steps can be achieved, for example, in the fabrication of external contacts on the substrate. Typically, in elongated piezoelectric ceramic devices, external electrodes are located at both ends of the substrate. This positioning of the electrical contacts increases costs in mass production and limits the possibilities for electrical connections. Thus, for example, FPC connections become difficult or impossible to achieve. By placing the external electrodes side-by-side on the single longitudinal side of the piezoelectric actuator 1, production costs can be essentially halved, as both external electrodes can be applied in a single, common process step. Furthermore, the piezoelectric actuator 1 can be connected via wiring element 40 formed by an FPC, as described above, which reduces the overall space requirement in the system integration of the tactile device 100 and simplifies operation. This also reduces production costs, especially in mass production, because the connection process for wiring the wiring element 40 is performed only on one side of the piezoelectric actuator 1. Furthermore, processes such as reflow soldering, laser soldering, thermoforming, or the use of anisotropic conductive film (ACF) can only be reasonably used with respect to the aforementioned geometry.

[0083] As described above, the amplifying element 30 is fixed to the piezoelectric actuator 1 by means of the connecting layer 20 with a corresponding fixing area 39. In this configuration, there is a risk of delamination of the amplifying element 30 when the tactile device operates under harsh conditions, i.e., at elevated temperatures and / or in an atmosphere with high humidity and / or other harmful substances. During operation, deformation of the piezoelectric actuator 1 and the amplifying element 30, as described above, particularly shear forces, are applied to the connecting layer 20, which, as described, may be, for example, made of or composed of an adhesive. Most commercially available adhesives have reduced shear strength under harsh conditions, especially at elevated temperatures. If the applied shear force exceeds the shear strength of the adhesive, this can cause the connecting layer to peel off over time. Typically, initial cracks appear at the edges of the connecting layer, which propagate until the associated fixing area is completely delaminated.

[0084] As demonstrated in the simulations, delamination is primarily induced by two factors. The first factor is the potential shrinkage and expansion of the ceramic substrate material beneath the fixed region 39 during operation. The second factor is the force acting perpendicular to the bonding layer 20 due to the enhanced movement of the amplifying element 30 during operation. Simulations show that, during operation, the anticipated shear load induced by these two factors on the bonding layer may be equal to or higher than the shear strength of most commercially available adhesives. Furthermore, the shear strength of the adhesive is temperature-dependent, meaning that increased temperature may lead to a decrease in shear strength. For most adhesives, the shear strength at elevated temperatures is lower than the shear load typically acting during operation as determined by simulations. Long-term operation may lead to cracks in the bonding layer at the interface with the fixed region of the amplifying element. After the appearance of such cracks, each subsequent operation promotes crack growth along the contact surface from the bonding layer to the amplifying element until delamination occurs in the corresponding fixed region. Crack propagation is primarily caused by the second factor mentioned above.

[0085] To enhance the reliability of the fixation of the amplifying element 30 at the piezoelectric actuator 1 via the fixed region 39, the tactile device 1 also includes at least one fixation improvement element. The embodiments for at least one fixation improvement element described below can also be provided in the foregoing embodiments. Furthermore, the embodiments for at least one fixation improvement element can be combined such that multiple described fixation improvement elements can be provided in the tactile device 100.

[0086] In particular, at least one fixed improvement element 50 may be part of one amplification element 30 or two amplification elements 30. In particular, at least one fixed improvement element 50 may have or be a structure in or at least one amplification element, which is set and configured to, for example, resist the shear force-induced peeling effect described above.

[0087] exist Figure 3AAn embodiment of a tactile device 100 with a fixed improvement element 50 is shown. Figure 3B The two amplifying elements 30 of the tactile device 100 are shown in the figure, while Figure 3C Only one of the amplifying elements 30 is shown in the image.

[0088] The amplifying element 30 has a fixing improvement element 50 in each fixing region 39. The fixing improvement element 50 is respectively formed at the fixing surface 390 of each fixing region 39 facing the substrate and thus towards the piezoelectric actuator 1, and is formed by a surface structure in which a portion of the connecting layer is disposed. The corresponding surface structure in the illustrated embodiment has at least one recess 51 or is configured as such a recess. Through the corresponding recess 51, which, for example, can form a wedge-shaped depression in the fixing surface 390, a local increase in the amount of material used in the connecting layer can be achieved, thereby achieving a locally greater thickness of the connecting layer. Particularly preferably, the recess 51 is formed at the edge of the edge region 32 of the fixing region 39 facing the travel region 31. At the edge of the edge region 32 facing the travel region 31, there may be a particularly high tendency for peeling, which can be offset by a locally greater thickness of the connecting layer.

[0089] Furthermore, in the described and subsequent embodiments, the thickness of the bonding layer 20 can be increased by applying prepreg 21 to precisely define the thickness, such as... Figure 4 As indicated in the description, the prepreg 21 can be a basic component of the circuit board, as described in the overview section, and can have a glass fiber fabric impregnated with an epoxy adhesive. The specific thickness of the bonding layer 20 can be adjusted by using multiple fabric layers, which are then filled with adhesive 22.

[0090] exist Figures 5A to 5C In the middle, in with Figure 4 A to Figure 4 Another embodiment is shown in the view corresponding to view C, wherein the fixing improvement element 50 has a surface enlargement structure 52 as a surface structure, in which at least a portion of the connecting layer is provided. The surface enlargement structure 52 is formed in the form of a groove or recess, such as a longitudinal groove, or, as shown, a transverse groove. By means of the corresponding surface enlargement structure 52, the interface between the fixing surface 390 and the corresponding connecting layer can be increased, thereby improving the fixing effect of the connecting layer.

[0091] The described fixed improvement element 50, configured as a surface structure in the fixed surface 390, can form measures to reduce crack initiation, particularly by increasing the thickness of the connecting layer inside the fixed region 39, i.e., towards the edge of the corresponding travel region 31. By increasing the thickness of the connecting layer in said region, the acting shear load can be distributed over a larger volume of the connecting layer material, thereby reducing the maximum shear load in the fixed region 39. In the two illustrated embodiments, the fixed region 39 is therefore divided into two regions, namely an outer region away from the corresponding travel region 31 and an inner region towards the corresponding travel region 31. According to Figures 3A to 3C In one embodiment, the corresponding outer region has a thinner portion of the connecting layer, which reinforces the integral connection between the amplifying element 30 and the piezoelectric actuator 1, while the corresponding inner region contains a thicker portion of the connecting layer to distribute the shear load. According to... Figures 5A to 5C In this embodiment, the corresponding internal area is preferably reduced to half the thickness of the plate, and the grooves or recesses are preferably formed perpendicular to the longitudinal direction of the tactile device 100. This increases the thickness of the connecting layer and the area of ​​the corresponding fixing region 39 that interacts with the connecting layer.

[0092] exist Figures 6A to 6C In the middle, in with Figure 4 A to Figure 4 Another embodiment is shown in the view corresponding to view C, wherein each fixing improvement element 50 has at least one wing-shaped element 53 adjacent to the fixing region 39, wherein each wing-shaped element 53 extends at least partially along the side (longitudinal side in the illustrated embodiment) of the piezoelectric actuator 1 adjacent to the main surface. The wing-shaped element 53 is integrally formed with the corresponding fixing region 39 and forms a tab or clip that covers or surrounds a portion of the side.

[0093] For each of the fixed improved elements 50 configured as wing-shaped elements 53, the connecting layer is preferably provided not only between the fixed surface 390 and the corresponding main surface of the piezoelectric actuator 1, but also additionally between the wing-shaped element 53 and the piezoelectric actuator 1. This allows the wing-shaped element 53 to increase the adhesion area between the amplifying element 30 and the piezoelectric actuator 1. Furthermore, by providing the wing-shaped element 53 on the side of the substrate of the piezoelectric actuator 1, support and force output different from that in the fixed region 39 can be achieved, thereby resisting peeling effects. Additionally, the corresponding connecting layer can be additionally provided between the wing-shaped element 53 of one amplifying element 30 and the fixed region 39 and / or the wing-shaped element 53 of another amplifying element 30, such that the two amplifying elements 30 are fixed to each other between the corresponding wing-shaped element 53 and / or fixed region 39 by the connecting layer.

[0094] exist Figures 7A to 7C In the middle, in with Figure 4 A to Figure 4 Another embodiment is shown in the view corresponding to view C, wherein the fixed improvement element 50, configured as a wing-shaped element 53, also has a toothed structure 54, which is provided and configured for engagement with the complementary toothed structure 54 of the wing-shaped element 53 or the fixed region 39 of the corresponding other amplifying element 30. Figure 7D A portion of the tactile device 100 is shown. Figure 7E The image shows a longitudinal view of the tactile device 100. A connecting layer is preferably additionally disposed between the toothed structures 54 of the two amplifying elements 30.

[0095] Furthermore, in the illustrated embodiment, the amplifying element 30 has, purely exemplarily, a connecting plate 31' for mounting the tactile device 100 at the travel region 31. Each of the connecting plates 31' is adjacent to and extends away from the corresponding travel region 31. The connecting plate 31' preferably extends away from the piezoelectric actuator 1 and the corresponding travel region 31 along the width direction, thereby preferably forming an angle of 90° or substantially 90° with the longitudinal side of the piezoelectric actuator 1 and the travel region 31. In the transition between the travel region 31 parallel to the longitudinal side direction and the connecting plate 31', the illustrated amplifying element 30 has an amplifying region 31'', particularly an amplifying region 31'' bent at an angle of 180° or substantially 180°. By bending at 180° or substantially 180°, it is feasible to centrally direct the force of the travel movement to the fixed region 39, such as Figure 7E As can be seen, this can avoid or at least reduce the torsion and twisting of the amplifying element 30.

[0096] In addition, such as Figure 7F and Figure 7G As indicated, the connecting plate 31' can be secured to the corresponding travel region 31 by means of at least one connecting element 37. The at least one connecting element 37 may, for example, be welded or bonded, and may be configured as one or more weld points, weld seams, bond points, and / or bond seams. The connecting element 37 between the travel region 31 and the connecting plate 31', for example as... Figure 7F The solder joints or adhesive joints indicated in the document, or as shown in the document. Figure 7G The welds or adhesive seams indicated herein, as well as the amplification region 31'', can increase the stiffness of the amplification element 30 so that energy can be transferred with very little loss. This can result in enhanced tactile feedback. Embodiments described later may also have a connecting plate or a connecting plate and an amplification region, but for clarity, no reference numerals are provided.

[0097] exist Figure 8A and Figure 8B Another embodiment is shown, wherein... Figures 7A to 7DCompared to the previous embodiment, the amplifying element 30 extends beyond the piezoelectric actuator 1 in the longitudinal direction. Figure 8A The diagram corresponds to Figure 7A The illustration shows a tactile device 100, while Figure 8B The diagram shows a piezoelectric actuator 1 with only one of the connecting elements 30. By extending the amplifying element 30 beyond the piezoelectric actuator 1 in the longitudinal direction, protection of the edges in the region of the end face 16 can be achieved. Unlike the aforementioned variant, the protruding region does not form a clip that matches the shape of the piezoelectric actuator 1, but rather results in a protrusion in the longitudinal direction. This protrusion can be used as stress relief for possible electrical connections such as the flexible wiring element described above. The enclosed area can be filled with the material of the connecting layer, so that the end face 16 of the piezoelectric actuator 1 can be covered by the material of the connecting layer and prevented from misoperation.

[0098] exist Figures 9A to 9C In the middle, in with Figure 4 A to Figure 4 Another embodiment is shown in the view corresponding to view C, wherein each of the fixed regions 39 of the amplifying element 30 has two wing-shaped elements 53 with toothed structures 54 as fixed improvement elements 50, the wing-shaped elements extending at least partially along two opposing longitudinal sides of the piezoelectric actuator 1.

[0099] Furthermore, each of the amplifying elements 30 has a stabilizing region 31''' adjacent to the travel region 31, extending from the travel region 31 toward the piezoelectric actuator 1. In particular, the stabilizing region 31''' can be formed by bending, i.e., an extension of the travel region 31 along a direction perpendicular to the longitudinal direction of the piezoelectric actuator 1, preferably bent at 90° or substantially 90° toward the piezoelectric actuator 1. The stabilizing region 31''' reinforces the travel region 31.

[0100] exist Figures 10A to 10C In the middle, in with Figure 4 A to Figure 4 Another embodiment is shown in the view corresponding to view C, wherein, compared with the aforementioned embodiment, the fixed improved element 50 portion configured as wing-shaped element 53 extends above the end side of piezoelectric actuator 1.

[0101] Combination Figures 6A to 11C The described wing-shaped element 53 particularly functions as a clamp, which partially surrounds the piezoelectric actuator 1, and preferably forms a clamp-like structure that engages with each other via toothed structures 54 on each side of the fixing region 39. In particular, the fixing region 39 and the wing-shaped element 53 can form a closed structure, which is filled or even covered by a connecting layer material. In a preferred variation, such as... Figures 7A to 9CAs shown, the wing-shaped element 53 and the toothed structure 54 are configured as mirror images of each other. When the tactile device 100 is fully installed, the fixing region 39 and the wing-shaped element 53 completely surround the piezoelectric actuator 1 within the fixing region 39.

[0102] exist Figures 11A to 11C , Figures 12A to 12C and Figure 13 Another embodiment of the tactile device 100 is shown, which has an element in the form of a clamping device 55 as a fixing improvement element 50, which is additional to the amplifying element 30 compared to the previous embodiment. Figure 11A and Figure 12A as well as Figure 11B and Figure 12B The views correspond to Figure 4 A's view or Figure 4 B's view, while Figure 11C and Figure 12C The clamping device 55 is shown separately. The clamping device 55 is moved within the fixing region 39 of the amplifying element 30 onto the amplifying element 30 and the piezoelectric actuator 1. Particularly preferably, the clamping device 55 is as follows: Figures 11A to 11C The image shown is circular, or as... Figures 12A to 12C The image shown is cap-shaped. Accordingly, the clamping device can preferably be configured as a ring element or a cap-shaped element.

[0103] To prevent crack growth in the bonding layer, a clamping device 55 can be used to resist forces acting perpendicular to the bonding layer. The fixing region 39 is clamped by the clamping device 55, preventing movement of the fixing region 39 relative to the main surface of the piezoelectric actuator 1 in the vertical direction. Additionally, a separate adhesive or bonding layer material can be applied to fix the position of the clamping device 55 on the fixing region 39. This also compensates for possible tolerances in the amplifying element 30, ensuring defect-free clamping during operation.

[0104] Alternatively or additionally, the clamping device 55 can be tapered, such as... Figure 13 As shown in the cross-sectional view of a tactile device 100 configured as a clamping device 55 in a hat-shaped element, in this embodiment, the amplifying element 30 additionally has a recess 51 for connecting the layer 20 as a fixing improvement element 50, such as in combination. Figure 4 A to Figure 4 As described in C. Due to its shape, the clamping device 55 can be secured by friction. However, applying an additional filler adhesive to the clamping device 55 can serve as an additional safety measure for reliability.

[0105] In corresponding Figure 1B The view Figure 14Another embodiment of the tactile device 100 is shown, wherein the fixed improvement element 50 has a passive region 56 in the piezoelectric actuator 1, i.e., a region that does not participate in the length change of the piezoelectric actuator 1. As mentioned above, one of the main reasons for the shear load in the fixed region 39 having the connecting layer 20 is the contraction and expansion of the region of the piezoelectric actuator 1 below the fixed region 39. Therefore, in the illustrated embodiment, the passive region 56 is disposed in the region of the fixed region 39 and preferably adjacent to the fixed region 39. Figure 14 As shown, the passive region 56 is the area of ​​the substrate 10 without any internal electrodes 13. Therefore, the areas of the main surfaces 11, 12 that contact the connecting layer 20 are passive surfaces that do not experience length changes. Simulations show that this can significantly reduce the shear load acting on the fixed region 39 during operation. In particular, it can be shown that the shear load is reduced below the shear strength of most commercially available adhesives, at least for some adhesives even at elevated temperatures, thus greatly expanding the possible material choices for the connecting layer 20. Particularly preferably, the fixed improvement element 50 configured as the passive region 56 can be coupled with... Figures 11A to 13 The clamping device 55 assembly of the embodiment.

[0106] exist Figure 15 The diagram shows a partial cross-sectional view of another embodiment of the tactile device 100, which, as a fixation improvement element 50, has a conformal coating 57 that covers at least the connecting layer 20 and the fixation area 39, and particularly preferably covers the entire tactile device 100. The conformal coating 57 covers the surface of the tactile device 100 in a substantially uniform thin layer and is made of a plastic material, such as a silicone- or acrylate-based plastic material, or composed thereof. By virtue of the conformal coating 57, which preferably covers all exposed surface areas, or at least all exposed surface areas except for the external electrodes, the connecting layer 20 can be protected from harmful external influences such as moisture, which can cause degradation of the connecting layer 20, thereby leading to deterioration of the fixation of the amplification element 30. Especially at high air humidity, such as 85% RH or higher, and high temperatures, such as 85°C or higher, the adhesive properties of the connecting layer 20 may be severely degraded during operation of the tactile device 100, which can significantly reduce its service life. The conformal coating 57, as a fixation improvement element 50, can resist this effect.

[0107] To manufacture the conformal coating 57, in a first step, the substrate 10 of the piezoelectric actuator 1 is manufactured such that all edges are rounded. Rounding the edges improves the coverage of the edges using the coating material. Typically, problems with poor edge coverage during coating are attributed to the high surface tension of the component to be coated and the mismatched viscosity of the coating material. Therefore, the viscosity of the coating material used for the conformal coating 57 is further set to achieve optimal coverage of the entire surface. This ensures that the rounded edges of the substrate 10 are covered by the coating material in subsequent steps, preventing the formation of diffusion paths for moisture to and from the connecting layer 20. Therefore, the sealed coating 57 is particularly advantageous for enabling reliable functioning of the tactile device 100. In another step, the piezoelectric actuator 1 with the fixed amplifying element 30 is coated with the coating material to form the conformal coating 57. This can be done, for example, by methods such as spraying, brushing, and dipping.

[0108] The tactile device 100 is not limited to the geometry of the foregoing embodiments. The tactile device 100 may also be based on, for example, the geometry of the foregoing embodiments. Figure 16A It is composed of one of the structural forms shown in Figure 18C.

[0109] especially, Figure 16A The embodiment shown in FIG18C may have at least one or more fixed improvement elements according to one or more of the foregoing embodiments.

[0110] like Figure 16A and Figure 16B As shown in the three-dimensional view and cross-sectional view, the amplifying element 30 can be flush with the end face 16 of the piezoelectric actuator 1 along the longitudinal direction, or even extend beyond the end face 16. Thus, the piezoelectric actuator 1 can be protected from impacts and shocks at the end face 16.

[0111] exist Figures 17A to 17C China and Israel Figure 4 A to Figure 4 The view corresponding to view C shows another embodiment, in which the amplifying element 30 has a plurality of travel regions 31, thereby having a plurality of tactile active regions, with intermediate regions 36 provided between the travel regions, which additionally form fixed regions 39 of the corresponding amplifying element 30 relative to the edge regions 32. The features described in the foregoing embodiments also apply to the intermediate regions 36 for the fixed regions 39 formed by the edge regions 32. Particularly preferably, the piezoelectric actuator 1 may also have a passive region in the region of the external electrode 15 (which is adjacent to the intermediate region 36 of the amplifying element 30) as a fixed improvement element.

[0112] In addition, such as Figure 18A To Figure 18C with Figure 4 A to Figure 4As shown in the view corresponding to view C, the travel region 31 of the magnifying element 30 may, for example, be directly adjacent to the edge region 32, without a transition region between the travel region 31 and the associated edge region 32.

[0113] exist Figure 19A and Figure 19B China and Israel Figure 7A and Figure 7C The view corresponding to the view shows another embodiment, wherein the magnifying element 30 serves as a fixed improvement element 50 having Figures 7A to 9C Implementation examples and Figures 10A to 10C The combination of embodiments. In particular, the amplifying element 30 has three wing-shaped elements 53 at each fixed region 39, two of which extend at least partially along two opposing longitudinal sides of the base of the piezoelectric actuator 1, and the other extends at least partially along an end side. In particular, one wing-shaped element 53 of the amplifying element 30 extends entirely over an end side.

[0114] exist Figures 20A to 20C China and Israel Figure 8A , Figure 8B and Figure 7C The view corresponding to the previous view shows another embodiment, which illustrates the foregoing embodiment and... Figures 9A to 9C The combination of embodiments, wherein the amplifying element 30 additionally has a stable region 31''' adjacent to the travel region 31 in the implementation of the foregoing embodiments, which extends from the travel region 31 toward the piezoelectric actuator 1.

[0115] exist Figure 21A and Figure 21B China and Israel Figure 7A The view and its corresponding cross-sectional view illustrate another embodiment, representing a modification of the aforementioned embodiment, wherein the connecting plate 31' of each of the amplifying elements 30 is configured as a separate component, which is fixed to the corresponding travel region 31 by means of the aforementioned connecting element 37, i.e., a welded or bonded portion. In other words, the connecting plate 31' of each of the amplifying elements 30 is a separately manufactured component, which is fixed to the corresponding travel region 31 by means of at least one connecting element 37. Each of the amplifying elements 30 is therefore a two-piece component, wherein the connecting plate 31' is preferably vertically disposed in the corresponding travel region 31 and fixed by welding or bonding in a material-fit manner.

[0116] exist Figure 22A and Figure 22B China and Israel Figure 2B The view corresponding to the view is for Figures 20A to 20C The embodiments exemplify the connection possibilities via flexible wiring element 40, as described above in conjunction with... Figure 2BAs described above. Flexible wiring element 40, as... Figure 2B In some embodiments, it can be a flexible circuit board, such as Figure 22A The wing-shaped element 53 of the amplifying element 30 shown can be disposed between the base of the piezoelectric actuator 1 and the wing-shaped element 53. For example, the flexible wiring element 40 can be clamped and / or bonded to the underside of the wing-shaped element 53. This allows for stress relief at the connection between the flexible wiring element 40 and the piezoelectric actuator 1. Alternatively, the wiring element 40 may not be disposed between the wing-shaped element 53 and the base, but rather as shown in the diagram. Figure 2B In some embodiments, it can freely traverse along the longitudinal side. Figure 22B As indicated, the flexible wiring element 40 can also be a multi-core cable, such as a multi-core cable with a plug. In this case, the wiring element 40 can also be combined as follows: Figure 22A The ground is disposed between at least one wing-shaped element 53 and the base.

[0117] The invention is not limited thereto by the description of the embodiments. Rather, the invention includes any new features and any combination of features, particularly any combination of features in the claims, even if the feature or combination itself is not explicitly stated in the claims or embodiments.

[0118] List of reference numerals

[0119] 1. Piezoelectric actuator

[0120] 10 Matrix

[0121] 11, 12 Main Surfaces

[0122] 13 Internal Electrodes

[0123] 14 Piezoelectric layer

[0124] 15 External Electrodes

[0125] 16 End Side

[0126] 17. Longitudinal side view

[0127] 18 upper side

[0128] 19. Lower side

[0129] 20 Connection Layer

[0130] 21 Prepreg

[0131] 22 Adhesives

[0132] 30 Amplifying elements

[0133] 31 Travel Area

[0134] 31' Connecting plate

[0135] 31'' Magnified area

[0136] 31''' Stable region

[0137] 32 Edge Area

[0138] 33 Transition Zone

[0139] 34 Thinning section

[0140] 35 Opening

[0141] 36. Middle area

[0142] 37 Connecting elements

[0143] 38 Free Zone

[0144] 39 Fixed Area

[0145] 390 Fixed surface

[0146] 40 Wiring components

[0147] 50 Fixed Improvement Components

[0148] 51 Recessed area

[0149] 52 Surface Enlargement Structure

[0150] 53. Wing-shaped element

[0151] 54. Tooth structure

[0152] 55 Clamping equipment

[0153] 56 Passive Region

[0154] 57 Coating

[0155] 100 tactile devices

[0156] B width

[0157] H height

[0158] L length

[0159] Direction of length change of R1

[0160] R2 travel direction

[0161] S stacking direction

Claims

1. A tactile device (100), comprising: - A piezoelectric actuator (1), having a substrate (10), and - At least one amplifying element (30) on the first main surface (11) of the piezoelectric actuator (1). The at least one amplifying element (30) has at least one fixed region (39) and a travel region (31), the at least one amplifying element (30) being fixed to the substrate (10) by means of the fixed region, the travel regions being spaced apart above the first main surface (11). A connecting layer (20) is provided between the at least one fixed region (39) and the first main surface (11).

2. The tactile device (100) according to claim 1, wherein the at least one fixed region (39) of the at least one amplifying element (30) is the edge region (32) or the middle region (36) of the at least one amplifying element (30).

3. The tactile device (100) according to claim 1 or 2, wherein the tactile device (100) has at least one fixing improvement element (50) configured to improve the reliability of fixing the at least one fixing region (39) at the substrate (10).

4. The tactile device (100) according to claim 3, wherein the at least one fixed improvement element (50) is part of the at least one amplifying element (30).

5. The tactile device (100) according to claim 4, wherein the at least one fixing improvement element (50) has a recess (51) at the fixing surface (390) of the at least one fixing region (39) facing the piezoelectric actuator (1), and at least a portion of the connecting layer (20) is disposed in the recess.

6. The tactile device (100) according to claim 5, wherein the recess (51) is formed at the edge of the at least one fixed region (39) toward the travel region (31).

7. The tactile device (100) according to any one of claims 4 to 6, wherein the at least one fixing improvement element (50) has a surface enlargement structure (52), in particular a groove, at a fixing surface (390) facing the piezoelectric actuator (1), wherein at least a portion of the connecting layer (20) is disposed in the surface enlargement structure.

8. The tactile device (100) according to any one of claims 4 to 7, wherein the at least one fixing improvement element (50) has at least one wing-shaped element (53) adjacent to the fixing region (39), the wing-shaped element extending at least partially along the side (16, 17) of the substrate (10) adjacent to the first main surface (11).

9. The tactile device (100) according to claim 8, wherein the at least one fixed improvement element (50) has two wing-like elements (53) that extend at least partially along two opposing longitudinal sides (17) of the base (10).

10. The tactile device (100) according to claim 8 or 9, wherein the at least one fixed improvement element (50) has two wing elements (53), wherein one wing element extends at least partially along the longitudinal side (17) of the base (10), and wherein the other wing element extends at least partially along the end side (16).

11. The tactile device (100) according to any one of claims 8 to 10, wherein the at least one fixed improvement element (50) has three wing elements (53), wherein two wing elements extend at least partially along two opposing longitudinal sides (17) of the base (10), and wherein another wing element extends at least partially along an end side (16) adjacent to the two opposing sides (17).

12. The tactile device (100) according to any one of claims 8 to 11, wherein the at least one wing-shaped element (53) is fixed to the base (10) and / or fixed to another amplifying element (30) by means of a portion of the connecting layer (20).

13. The tactile device (100) according to any one of claims 8 to 12, wherein the at least one wing-shaped element (53) has a toothed structure (54) configured to engage with a complementary toothed structure (54) of an additional amplifying element (30).

14. The tactile device (100) according to any one of claims 3 to 13, wherein the at least one fixing improvement element (50) has a prepreg (21) between the first main surface (11) and the fixing region (39) of the at least one amplifying element (30).

15. The tactile device (100) according to any one of claims 3 to 14, wherein the at least one fixed improvement element (50) has a clamping device (55) which is pushed in the fixing region (39) of the at least one amplifying element (30) onto the at least one amplifying element (30) and the substrate (10).

16. The tactile device (100) according to any one of claims 3 to 15, wherein the at least one fixed improvement element (50) has at least one passive region (57) in the piezoelectric actuator (1), the passive region being adjacent to the at least one fixed region (39).

17. The tactile device (100) according to any one of claims 3 to 16, wherein the at least one fixing improvement element (50) has a conformal coating (57) covering the tactile device (100).

18. The tactile device (100) according to any one of the preceding claims, wherein the at least one amplifying element (30) extends beyond the base (10) on a side opposite to the travel region (31).

19. The tactile device (100) according to any one of the preceding claims, wherein the fixed area (39) is covered by the connecting layer (20).

20. The tactile device (100) according to any one of the preceding claims, wherein the at least one amplifying element (30) has a connecting plate (31') adjacent to the travel region (31) for mounting the tactile device (100).

21. The tactile device (100) according to the preceding claim, wherein the at least one amplifying element (30) has an amplifying region (31'') in the transition between the travel region (31) and the connecting plate (31').

22. The tactile device (100) according to claim 21, wherein the connecting plate (31') is fixed at the travel region (31) by means of at least one connecting element (37).

23. The tactile device (100) according to claim 20, wherein the at least one amplifying element (30) has a connecting plate (31') for mounting the tactile device (100), the connecting plate being manufactured separately and fixed at the travel region (31) by means of at least one connecting element (37).

24. The tactile device (100) according to any one of the preceding claims, wherein the at least one amplifying element (30) has a stable region (31''') adjacent to the travel region (31), the stable region extending from the travel region (31) toward the piezoelectric actuator (1).

25. The tactile device (100) according to any one of the preceding claims, wherein the piezoelectric actuator (1) has a longitudinal side (17) and two external electrodes (15) are disposed on the longitudinal side for electrically contacting the tactile device (100).

26. The tactile device (100) according to the preceding claim, wherein the flexible wiring element (40) is connected to the two external electrodes (15).

27. The tactile device (100) according to claim 26, wherein the flexible wiring element (40) is a flexible circuit board or a multi-core cable.

28. The tactile device (100) according to claim 26 or 27 and any one of claims 8 to 13, wherein a portion of the flexible wiring element (40) is disposed between the at least one wing-shaped element (53) and the side surface (16, 17) of the base (10).

29. The tactile device (100) according to any one of claims 26 to 28 and claim 17, wherein a portion of the flexible wiring element (40) together with the piezoelectric actuator (1) and the at least one amplifying element (30) is covered by the conformal coating (57).

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