Device for generating a haptic signal, apparatus comprising the device, and method for manufacturing the device

Abstract

A device (1) for generating a haptic signal has one or more piezoelectric elements (3) and at least one connection element (4, 4a, 4b) for electrical connection of the piezoelectric element (3).

Description

[0001] P2024,0090 WO N January 30, 2025 - 1 - Description Device for generating a haptic signal, device comprising the device, and method for producing the device The present invention relates to a device for generating a haptic signal. In particular, the device can be used in a touch-sensitive display to generate a haptically perceptible signal for a user upon touch. Such devices are known, for example, from US 2022 / 0066557 A1 and WO 2022 / 171492 A1. In these devices, piezoelectric elements are attached to a carrier, and a mechanical resonant oscillation of the carrier is generated by applying an alternating voltage to the piezoelectric elements. The device is attached to the back of a touch-sensitive screen and generates a standing surface wave on a front side of the screen, whereby a haptically perceptible signal for a useris generated. In such devices, a high mechanical deflection is required. The mechanical fastening and electrical contacting of the piezoelectric elements are crucial for the performance of the device. US 2022 / 0066557 A1 describes a connection of the piezoelectric elements to the carrier by means of a conductive adhesive. WO 2022 / 171492 describes a connection of the piezoelectric elements by means of a solder connection, which produces less mechanical damping on the vibration than an adhesive connection and thus enables increased performance. P2024,0090 WO N January 30, 2025 - 2 - An object of the present invention is to provide a device for generating a haptic signal with improved properties. For example, the electrical contacting of the piezoelectric elements can be improved. According to a first aspect, a device for generating ahaptic signal, one or more piezoelectric elements. The device has at least one connection element for electrically connecting the piezoelectric elements. The device can have a plurality of piezoelectric elements. The piezoelectric elements can be arranged next to one another. The piezoelectric elements can, for example, be arranged such that the piezoelectric elements do not overlap when viewed from above onto an electrode surface. For example, the piezoelectric elements are arranged in a single row. Other arrangements are also possible. For example, the device can have only a single piezoelectric element. All statements regarding a piezoelectric element apply accordingly to a plurality of piezoelectric elements and vice versa. The piezoelectric element can have any geometric shape. Preferably, the piezoelectric element can have a flat shape."Flat" in this context means in particular that the piezoelectric element has a significantly smaller spatial extent along a vertical axis than it has dimensions in a longitudinal and width axes. P2024,0090 WO N January 30, 2025 - 3 - The piezoelectric element can have a monolithic piezoelectric layer. The piezoelectric layer can be arranged between two electrodes arranged on the outer surfaces of the piezoelectric element. In particular, the outer electrodes can be arranged on the main surfaces of a flat piezoelectric element. The piezoelectric element can also be designed as a multilayer element which has piezoelectric layers and inner electrodes stacked one above the other. The piezoelectric element can be a piezoelectric ceramic, for example a lead-containing ceramic such as lead zirconate titanate ceramic (PZT ceramic) or a lead-free ceramic such asBismuth ferrate barium titanate (BFO-BT ceramic). Alternatively, the piezoelectric element may comprise a piezoelectric polymer, for example, polyvinylidene fluoride (PVDF). Alternatively, the piezoelectric element may comprise, for example, a composite material. The device may comprise a carrier. The piezoelectric element may be arranged on the carrier, in particular attached to the carrier. The piezoelectric element may be attached to the carrier, for example, by means of a joining agent. It is also possible for the piezoelectric element to be deposited on the carrier. "Deposition" is also intended to be encompassed by the term "attached" hereinafter. A haptic device may comprise the carrier, wherein the piezoelectric elements are arranged on the carrier, in particular attached. For example, the carrier may be designed to be attached to a touch element of a haptic device. The carriercan also be formed directly by the touch element. The device can have only one or several carriers. At least one piezoelectric element can be fastened to each carrier. The device can have any number of carriers, on which any number of piezoelectric elements can be fastened. For example, a plurality of piezoelectric elements is fastened to one, in particular a single, carrier. The carrier can be designed to be arranged, in particular fastened, to a touch element or another element of a device. The carrier can be fastened, for example, by means of a joining means or can also be deposited on the element. Here, too, the term "fastening" is intended to include deposition. A touch element is designed to be touched by a user directly or indirectly, e.g., via a pin. TheThe haptic signal generated by the device is output to the user. For example, the touch element is a screen, in particular a touch-sensitive screen. The touch element can also be designed as an input element that can be used for input and outputs haptic feedback. The carrier is attached, for example, to a back of the touch element. The piezoelectric element can, for example, be designed as an actuator and, at the same time, as a sensor for detecting an input. It is also possible for the piezoelectric element to function only as an actuator. It is also possible for the carrier to be formed by the touch element and thus be an integral part of the touch element. The carrier can protrude from a remaining back of the touch element. The carrier can also be designed flush with the remaining back of the touch element. The carrier can also be designed asanother element of the device, for example, as an intermediate element to transmit the haptic signal to a touch element. An integral design of carrier and touch element has the advantage that there are fewer joints in the device. Such joints are often critical for the risk of failure of the device due to different thermal expansion coefficients of the elements to be connected and the mechanical movement. A first joint can be the connection from the carrier to the one or more piezoelectric elements. A second joint can be the connection from the touch element to the carrier. A joint can be formed using an electrically conductive or electrically non-conductive joining means. In particular, a joint can be formed using an adhesive, solder, welding, friction welding, thermode welding, or bonding means. For example, a joint can be formed using a conductive adhesive, a non-conductive adhesive, aEpoxy adhesive, a hard solder, a soft solder, a lead-containing solder, or a lead-free solder. It is also possible for the piezoelectric elements to be connected to the carrier without a joining agent. In particular, in the case of a piezoelectric element comprising a piezoelectric plastic or a composite material with a plastic as the matrix material, no joining agent may be present for arranging the piezoelectric element on the carrier. In this case, the piezoelectric element can be deposited directly onto the carrier during production from solution or melt and thus formed directly onto it as a materially bonded piezoelectric element. The piezoelectric element is therefore not formed directly from the carrier material, as in other embodiments, but is applied to the carrier material. If the piezoelectric elements are arranged directly on the back of a touch elementare, any joining means between a piezoelectric element and a touch element can be dispensed with. Likewise, a carrier can be deposited directly onto a touch element or another element of a device and thus bonded materially. The device can also be designed such that it is first provided in a carrierless form and then attached to a device. For example, the device is attached to the back of a touch element or an intermediate element. The carrier can comprise an electrically conductive or electrically non-conductive material. The carrier can comprise, for example, a metal, a plastic, a glass, a ceramic, or a (fiber) composite material. For example, the carrier can be aluminum, steel, titanium, boron-silicate glass, Plexiglas, aluminum oxide, GRP (glass fiber reinforced plastic) or CFRP (carbon fiber reinforced plastic).If the carrier is not directly formed by the element in which it is intended to stimulate a haptically perceptible signal, the carrier can comprise a similar or identical material to the element or can be adapted to a material of the element in terms of properties, in particular the mechanical and / or thermomechanical properties. The element can be, for example, a touch element of a haptic device. For example, the element can comprise an aluminum, glass, or plastic material. In this case, it can be advantageous if the carrier also comprises a similar or identical aluminum, glass, or plastic material. In the case of an element comprising a plastic material, for example Plexiglas, the device can comprise a (fiber) composite material, for example a GRP material. In particular, a matrix material for a (fiber) composite material of the carrier can be a plastic material of theobject. The connection element can be attached to the carrier. Alternatively or additionally, the connection element can be attached to at least one piezoelectric element. The connection element can also be attached to the carrier and at least one piezoelectric element. For example, the connection element can be attached directly to a piezoelectric element and directly to the carrier. By attaching it to the piezoelectric element, one polarity can be contacted, and by attaching it to the carrier, the other polarity can be contacted. It is also possible for the device to have multiple connection elements. These can be attached to the carrier and / or to one or more piezoelectric elements. The connection elements can be designed for connecting the same polarity or different polarities. For example, multiple connection elements are provided which are designed for connecting the same polarityare formed. The connection elements can be attached at different positions of the device. By subdividing the connections in this way, mechanical damping of the device can be reduced. In addition, mechanical damping can be distributed evenly across the device. Furthermore, the connection elements can be led out of the device at different points, for example, at opposite end faces. This allows for flexible further contacting. The at least one connection element can be attached to at least one carrier. In particular, the connection element can be attached only to the carrier and not to any piezoelectric element. In particular, in the case of multiple connection elements, all connection elements of the device can be attached only to one carrier and not to the piezoelectric elements. By attaching the connection element to the carrier, in particular only to the carrier,a lower damping of the vibration can be achieved than with attachment to the piezoelectric elements. In particular, the connection element can be attached to the carrier in an area that expands little during vibration. In addition, when the connection element is attached to the carrier, the reliability of the connection can be increased because the connection is subjected to less mechanical stress. The one or more piezoelectric elements can, for example, be attached to a main surface of the at least one carrier. The main surface can, for example, have a rectangular shape. The piezoelectric elements can, for example, be arranged along a row in the longitudinal direction of the main surface. The one or more connection elements can be attached next to a piezoelectric element. If a carrier is present, the connection elements can be attached to the carrier.In an initially support-free design, the connecting elements can be designed to be attached to a support later. "Next to" in this context means in particular that no further piezoelectric element is located between the attached region of the connecting element and the piezoelectric region. The one or more connecting elements can be attached between two adjacent piezoelectric elements. "Adjacent" in this context means that no further piezoelectric element is located between the piezoelectric elements. In such an arrangement, the connecting element can be attached near a neutral fiber, which does not experience any change in length upon deformation of the device or the support. Thus, such an attachment point is low-damping and reliable. P2024,0090 WO N January 30, 2025 - 10 - It is also possible for the at least one connecting element to be attached to one or morepiezoelectric elements, in particular on a top side of a piezoelectric element. A top side is a side that faces away from a side of the piezoelectric element that is designed for attachment to a carrier. The attachment “on” or “at” a piezoelectric element or carrier means in particular that the attachment is located directly on the piezoelectric element or the carrier. A connection element can have an electrical conductor. A connection element can additionally have electrical insulation. A connection element can, for example, have a flexible, insulating carrier material and at least one conductor, in particular a conductor track, that is applied to the carrier material. The conductor track can be embedded in an electrically insulating carrier material. In particular, a connection element can be designed in the form of a flexible printed circuit board. According to aIn one embodiment, the piezoelectric elements are arranged, in particular fastened, to a carrier. The connecting element is fastened to the carrier and / or to at least one of the one or more piezoelectric elements, wherein the connecting element is designed as a flexible printed circuit board. This embodiment is particularly advantageous because a particularly low-damping connection can be made using a flexible printed circuit board that is fastened directly to the carrier and / or to a piezoelectric element. Furthermore, no additional contact points are required for further contacting. The connecting element can be attached to the carrier and / or to the piezoelectric element in such a way that the connection is made at vibration nodes and other non-vibrating points, so that mechanical damping of the device can be kept as low as possible and maximum utilization of the haptic signal is possible.A connection element can be designed to contact only one polarity. The other polarity can be contacted, for example, via another connection element or via a carrier. Alternatively, it is possible for a connection element to be designed to contact both polarities. In this case, a connection element can have two or more electrical conductors, in particular conductor tracks. Likewise, several electrical insulations can be present. For example, a connection element can be designed to contact only one polarity, but have several conductor tracks. In particular, a connection element can be designed in the form of a flexible printed circuit board with several conductor tracks. A connection element can extend over the entire or almost the entire length of a carrier and / or along all piezoelectric elements. In particular, a fastening of the connection element can be provided next to each piezoelectric element.Alternatively or additionally, a connection element can be attached to each piezoelectric element. A combination of attachment next to and attachment on the piezoelectric elements is also possible. This enables particularly simple attachment of all piezoelectric elements. Alternatively, a connection element can extend only over a short distance along the length of the carrier and / or along the one or more piezoelectric elements. For example, a connection element extends along less than half the length. In particular, the connection element is attached to the carrier only next to a few piezoelectric elements or is provided for attachment to a carrier, in particular next to less than half of the piezoelectric elements. Thus, fewer contact points of the connection element are present or provided on the carrier. This has the advantage that the connection elementis more cost-effective. Furthermore, such a connection element contributes less to the attenuation of a haptically perceptible signal. The connection element can contact both a first electrode of a piezoelectric element and a second electrode of the piezoelectric element. For example, the connection element has a contact surface for contacting the second electrode on a bottom side and a further contact surface for contacting the first electrode on a top side. The contact surface is, for example, directly attached to the carrier and electrically connected to it, so that the second electrode can be electrically connected via it. The first electrode is connected to the further contact surface, for example, by a bonding wire. The contact surfaces can lie directly above one another. This makes contacting both electrodes efficient and possible with few connection points, allowing a particularly low-attenuation connection.can. P2024,0090 WO N January 30, 2025 - 13 - In another embodiment, it is also possible for the connection element to contact a first electrode and a second electrode via contact surfaces that are arranged on the same side of the connection element, for example, a bottom side. In this case, for example, both contact surfaces are connected to conductive regions on the carrier. It is also possible for only one contact surface to be connected to the carrier, in particular for contacting a first, lower electrode, and the further contact surface to be attached directly to the piezoelectric element, for contacting the second, upper electrode. A connection element can have at least one contact finger that is attached to the carrier. In particular, a connection element can have a web from which the contact finger extends. The web can in this case be in plan view onto a main surface of the carrier or the upper sides of the piezoelectricElements can be arranged next to the carrier or the piezoelectric elements and extend in the longitudinal direction of the carrier or the arrangement of piezoelectric elements. The contact fingers can extend from the web into an area next to or between the piezoelectric elements or onto the piezoelectric elements. A connection element can partially or completely cover one or more of the piezoelectric elements when viewed from above on a main surface. Alternatively, a connection element can not cover any of the piezoelectric elements, neither partially nor completely, when viewed from above on a main surface of the device. The web can in particular be arranged in such a way that it does not cover the carrier or is not intended to cover a carrier. This has the advantage that damping of the vibration, and thus damping of a haptically perceptible signal, can be achieved by theConnection element can be kept low. A connection element can also have several webs. These webs can extend, for example, on different sides of the piezoelectric elements or a carrier. A web can have several contact fingers. These contact fingers can extend at different points along a web into an area between the piezoelectric elements. The one or more piezoelectric elements can each have a first electrode facing the carrier and a second electrode facing away from the carrier. If the device is still carrierless, the electrodes can each be designed to face or face away from a carrier. The connection element contacts, for example, at least the second electrode. It is also possible for the connection element to contact both electrodes. The connection element can be designed such that it is connected to one or moreof the piezoelectric elements. Alternatively, the connecting element can be designed such that it is not directly attached to any of the piezoelectric elements. Thus, contacting the upper, second electrode from the connecting element can be established by attachment to the carrier and not directly to the second electrode. P2024,0090 WO N January 30, 2025 - 15 - A contact finger of the connecting element can contact both polarities. The connecting element can have several such contact fingers. It is also possible for a first contact finger of the connecting element to contact only one polarity, for example, first electrodes, and a second contact finger to contact only the other polarity, for example, second electrodes. Furthermore, it is also possible for the connecting element to contact only the second electrodes. The second electrode can be electrically connected to a connecting element via a connecting structure.The connecting structure extends, in particular in plan view of a main surface of the carrier or the arrangement of piezoelectric elements, beyond the contacted piezoelectric element. In particular, the connecting structure can extend longitudinally beyond the piezoelectric element. The connecting structure is fastened, for example, with a first end to the second electrode and with a second end to a contact surface of a connection element. In one embodiment, the connecting structure has a bonding wire. This can, in particular, be a thick wire. The bonding wire can be fastened by bonding to the second electrode on the top side of a piezoelectric element and extend to a contact surface of a connection element and here also be fastened to an top side by bonding. The connection element can be fastened to the carrier on its underside or for fastening to an undersidea carrier. P2024,0090 WO N January 30, 2025 - 16 - A connection by bonding has the advantage that a connection can be established in a process-safe and reliable manner. Since the connection is made on an upper side of the piezoelectric element and the connection element, the connection can also be visually inspected. A connection by thick-wire bonding is particularly easy to handle due to the rigidity of the bonding wire. The bonding wire can extend in the longitudinal direction of the device. In this way, the damping of the vibration can be kept low. In a further embodiment, the connection structure has a conductive region on the carrier. As explained above, the carrier can also be a touch element or another element of a device. To contact the upper, second electrode, the second electrode can be guided to the underside of the piezoelectric element. TheThe piezoelectric element is placed on the conductive region and electrically connected thereto. The connection element is also placed on the conductive region and electrically connected thereto. The device can further comprise a contact structure for electrically connecting one of the piezoelectric elements to the connection element via at least one further piezoelectric element. This is particularly advantageous if the connection element does not extend along the entire length of the carrier and / or the arrangement of the piezoelectric elements and, in particular, is not attached to the carrier next to each of the piezoelectric elements or is designed for attachment to a carrier. P2024,0090 WO N January 30, 2025 - 17 - According to one embodiment, a contact structure comprises a bonding wire and a contact surface. In particular, the contact structure can comprise a bonding wire extending from a piezoelectric element to theThe contact surface extends and have a further bonding wire that extends from the contact surface to a further piezoelectric element. The further piezoelectric element can then be connected to a connection element by means of a connecting structure or can be connected to a further contact structure. The bonding wire for the contact structure can be designed like the bonding wire for the previously described connecting structure. According to a further embodiment, a contact structure has a conductive region on a carrier, on which two adjacent piezoelectric elements are placed. To contact the upper, second electrode, the second electrode is guided to the underside of the piezoelectric element. In particular, a piezoelectric element can be placed on the conductive region and electrically connected to it, and a further piezoelectric element can be placed on the same conductive region andThe further piezoelectric element can then be connected to the connection element by means of a connecting structure or connected to a further contact structure. The conductive regions can be formed like the previously described conductive regions for the connecting structure. Such a contact structure has the advantage that fewer separate parts have to be connected to one another and the formation of a conductive region is easier to handle and more cost-effective than a connection via a bonding wire. It is possible to combine the above-described embodiments for the connecting structure and the contact structure. For example, in one device, the connecting structure is formed by means of bonding wires and the contact structure by means of conductive regions. Conversely, in one device, the connecting structure can also be formed by means of conductive regions.and the contact structure can be formed by means of bonding wires. It is also possible for the contact structure and the connection structure to be formed accordingly. According to a further aspect, a device for outputting a haptic signal has a surface for interaction with a user and a device for generating a haptic signal is formed on the surface. In particular, this can be a deformation, in particular a vibration, of the surface. The device can in particular be the device described above. The device can in particular be designed as a touch-sensitive screen. The device can have a touch element which has the surface, wherein the carrier is attached to the touch element, in particular to a back side of the input element. The carrier can also be attached to another element of the device. The element can be coupled to a touch element, so thatthe deformation of the object is transferred to the touch element. P2024,0090 WO N January 30, 2025 - 19 - Alternatively, it is also possible for the carrier to be formed by the touch element and thus be an integral part of the touch element. The carrier can protrude on a rear side of the touch element. The rear side of the touch element can also be flat. An integral design of carrier and touch element has the advantage that fewer joining points, in particular having a joining means, are present in the device. Such joining points are often critical for the risk of failure of the device due to different thermal expansion coefficients of the elements to be connected and the mechanical movement. A joining point provides a mechanical and / or electrical coupling between two components. A first joining point can be the connection from the carrier to the piezoelectric elements. A second joining point can be the connection from the touch elementto the carrier. Additional joints may also be present. First, second, third, or further joints can be joined using the same means or different means. The selection of the individual joining means and the coordination between multiple joining means can be based on the mechanical coupling, the (thermo-)mechanical behavior, and / or the long-term stability of the joint. It is also possible for the piezoelectric element to be deposited on the contact element or another element of the device, so that in this case, too, no joint having a joining means is present. To improve the stability of the overall system, the parts to be joined can be adapted in terms of their material in terms of their P2024,0090 WO N January 30, 2025 - 20 - thermal expansion coefficient. Furthermore, mechanical stresses can be compensated for by the flexibility of the connecting material and / or the elements.In particular, the aforementioned properties can be coordinated and / or adjusted to the corresponding properties of the parts to be joined by the joining means. In this case, the properties of the joined component assembly can be optimized. However, a compromise between signal yield and compensation of mechanical stresses is necessary. According to a further aspect, a method for producing a device for generating a haptic signal and / or a device comprising the device is specified. This can in particular be the device and / or the device described above. Thus, all structural and functional properties of the device and / or the device also apply to the method and vice versa. In the method, one or more piezoelectric elements are connected to at least one connection element. A carrier can be provided and theOne or more piezoelectric elements are arranged, in particular fastened, on the carrier. For example, a joining agent is used. It is also possible for the piezoelectric elements to be deposited on the carrier. As explained with regard to the device, a carrier can be a separate element or also a touch element or another element of the device. P2024,0090 WO N January 30, 2025 - 21 - The connection element can be fastened to the carrier. For example, at least one of the piezoelectric elements is electrically connected to the connection element by bonding a bonding wire. Alternatively, for example, at least one of the piezoelectric elements is electrically connected to the connection element via a conductive region on the carrier. In addition, as described for the device, further piezoelectric elements can be connected to the connection element via a contact structure. The presentThe invention encompasses several aspects, in particular devices and methods. The features, properties and embodiments described for one of the aspects shall also apply accordingly to the other aspect. Furthermore, the description of the subject matter specified here is not limited to the specific embodiments. Rather, the features of the individual embodiments can be combined with one another - as far as technically expedient. The subject matter described here is explained in more detail below using schematic exemplary embodiments. They show: Figure 1A shows an embodiment of a device in perspective view, Figure 1B shows a detail of the device from Figure 1A in perspective view, P2024,0090 WO N January 30, 2025 - 22 - Figure 1C shows a detail around a contact point of a connection element in the device from Figure 1A in cross section, Figure 2A shows a carrier with piezoelectric elements in an embodiment of the device inperspective view, Figure 2B shows the carrier with piezoelectric elements in the device from Figure 2A in cross section, Figure 3A shows a further embodiment of the device in perspective view, Figure 3B shows a detail of a contact connection in the device from Figure 3A in perspective view, Figure 3C shows a detail of a contact surface in the device from Figure 3A in perspective view, Figure 4A shows a further embodiment of a device in perspective view, Figure 4B shows a detail of the device from Figure 4A in perspective view, Figure 5A shows a piezoelectric element for the device from Figure 4A in perspective view from below, Figure 5B shows a piezoelectric element for the device from Figure 4A in perspective view from above, Figure 6 shows a further embodiment of a device in P2024,0090 WO N January 30, 2025 - 23 - perspective view, Figure 7 shows a further embodiment of a device in perspectiveView, Figure 8 shows a further embodiment of a device in perspective view, Figure 9 shows a further embodiment of a device in perspective view, Figure 10 shows a further embodiment of a device in perspective view, Figure 11 shows a further embodiment of a device in perspective view, Figure 12 shows an embodiment of a device in sectional view, Figure 13 shows a further embodiment of a device in sectional view, Figure 14 shows a further embodiment of a device in sectional view. Preferably, in the following figures, the same reference numerals refer to functionally or structurally corresponding parts of the various embodiments. Figure 1A shows a device 1 for generating a haptic signal. The device 1 is designed, for example, to deflect a touch-sensitive screen P2024,0090 WO N January 30, 2025 - 24 - so that when touched by a user, a haptic impressionis created. The device 1 is designed, for example, to be attached to the back of a screen. The device 1 has a carrier 2 and a plurality of piezoelectric elements 3 attached thereto. The piezoelectric elements 3 are designed to cause the carrier 2 to oscillate when an electrical voltage is applied. For example, this oscillation has a frequency in the ultrasonic range. The movement of the piezoelectric elements 3 is transmitted to the carrier 2, so that the carrier 2 is also excited to oscillate in the ultrasonic range. The carrier 2 can, for example, be designed to be attached to a touch element, for example a haptic surface, of a haptic device. It is also possible for the carrier 2 to be formed directly by a touch element or another element of a haptic device. The carrier 2 can also have a different geometry than that shown here.For example, the carrier 2 can extend significantly laterally over the piezoelectric elements 3. The piezoelectric elements 3 are flat, for example, in the rectangular shape shown here. A round disc shape is also possible. The piezoelectric elements 3 can have a single piezoelectric layer or be designed as multilayer components. The piezoelectric elements 3 are designed as piezoelectric actuators and can be configured to generate vibrations with a frequency in the ultrasonic range. Vibrations with a frequency between 40 kHz and 120 kHz can be excited. In particular, frequencies between 60 and 80 kHz can be excited. The piezoelectric elements 3 can also be designed as sensors to detect pressure acting on a touch element of a haptic device. For the electrical connection of thepiezoelectric elements 3, the device 1 has a connecting element 4. The connecting element 4 is fastened to the carrier 2. The connecting element 4 is fastened next to the piezoelectric elements 3, in particular between the piezoelectric elements 3 on the carrier 2. To generate an oscillation, an alternating voltage can be applied to the electrodes 8, 9. Thus, the connecting element 4 is not directly fastened to the piezoelectric elements 3. In a top view of the carrier 2, the connecting element 4 does not partially or completely cover one of the piezoelectric elements 3. The connecting element 4 is spaced apart from all piezoelectric elements 3 in the longitudinal direction L. This has the advantage that the connecting element 4 and in particular the connection point of the connecting element 4 on the carrier 2 is exposed to a lower mechanical load during an oscillation than when fastened directly to a piezoelectric element 3 or when guided viapiezoelectric elements 3. In addition, a damping effect on the vibration by the connection element 4 can be kept low. P2024,0090 WO N January 30, 2025 - 26 - At the position of the connection point next to and between the piezoelectric elements 3, less strain occurs. In particular, the position of the connection point is as close as possible to a neutral fiber of the device 1. A neutral fiber is defined by the fact that it does not experience any change in length upon deformation of the composite of piezoelectric elements 3 and carrier 2. In particular, attachment can be as close as possible to a so-called "nodal point". The "nodal point" is a point in section parallel to the vertical axis of the carrier 2, at which no vibration occurs on the surface facing the piezoelectric elements 3. In the plan view of the device 1, this is in particular a point at which the neutral fiber runs along a surface of the carrier 2.runs. With a mechanical connection at this point, the signal attenuation can be kept low and the service life of the connection can be maximized. In the present embodiment, the connection element 4 extends in the longitudinal direction L along almost the entire length of the carrier 2. The connection element 4 merely does not extend along a single one of the piezoelectric elements 3. The connection element 4 has a web 5, from which a plurality of contact fingers 6 extend between the piezoelectric elements 3. In particular, the contact fingers 6 extend between directly adjacent piezoelectric elements 3 and are fastened there to the carrier 2. The connection element 4 has a comb-like shape. The connection element 4 has a connection surface 7 for external contacting. P2024,0090 WO N January 30, 2025 - 27 - Figure 1B shows an enlarged view of the contacting of the piezoelectric elements 3 by the connection element4. Figure 1B shows a cross-sectional view of an area around a contact point of the connection element 4. The piezoelectric elements 3 each have a first electrode 8 and a second electrode 9. The first electrode 8 has a first polarity and the second electrode 9 has a second polarity. The first electrodes 8 are each arranged on a surface of the piezoelectric element 3 that faces the carrier 2. The second electrode 9 is each arranged on a surface of the piezoelectric element 3 that faces away from the carrier 2. The piezoelectric elements 3 are electrically connected to the connection elements 4 via a connecting structure 10 in the form of bonding wires 11. The bonding wires 11 are each connected at one end to the second electrode 9 and at the other end to the connection element 4. The bonding wires 11 each lead from a piezoelectric element 3 to a contact finger 6 directly adjacent thereto. In particular, theConnection element 4 has a contact surface 12 in the region of the contact fingers 6, to which the bonding wire 11 is mechanically and electrically connected. The contact surface 12 is connected to an electrical conductor track 13 of the connection element 4, which leads to the connection surface 7. Thus, the connection element 4 provides an electrical connection of the second electrodes 9. Thus, the second electrode 9 is connected to the connection element 4 via bonding. In particular, the bonding wire 11 can be a thick wire, so that a connection is made via thick wire bonding. For example, the thick wire is made of aluminum. A connection by bonding has the advantage over other connection types, such as soldering or gluing, that a visual inspection of the contact point is possible, so that quality assurance measures can be easily implemented. Another advantage of wire bonding is theGood automation and reproducibility of the process control. A connection by thick wire bonding is particularly easy to handle due to the strength of the thick wire and has a high load-bearing capacity. The bonding wires 11 extend in the longitudinal direction L of the device 1. The bonding wires 11 thus have only a small connection cross-section to the longitudinal direction L, so that the bonding wires 11 lead to only minimal damping when the device 1 is stretched in the longitudinal direction L due to vibration. Thus, a large deflection of the device 1 can be achieved. The piezoelectric elements 3 are attached by their first electrodes 8 (see Figure 2B) to the carrier 2 by an electrically conductive connection. For example, the first electrode 8 is attached to the carrier 2 by a conductive adhesive or a solder connection. A solder connection has the advantage that the vibration is only slightly damped due to its high rigidity.In the case of an electrically conductive carrier 2, contact can be established via the carrier 2 to a further contact surface 14 of the connection element 4 facing the carrier 2. For example, the further contact surface 14 is attached to the carrier 2 with a conductive adhesive. It is also possible for the further contact surface 14 to be soldered to the carrier 2. The further contact surface 14 can also be designed directly as a fastening means. The further contact surface 14 is electrically connected to a further conductor track 15 of the connection element 4. The further conductor track 15 is led to the connection surface 7. Thus, the connection element 4 also provides an electrical connection of the first electrodes 8. The further contact surface 14 and the further conductor track 15 are separated from the contact surface 12 and the conductor track 13 by an electrically insulating layer 16. The insulating layer 16 forms, in particular, a carrierfor the conductor tracks 13, 15. The connection element 4 is designed in particular as a flexible printed circuit board (FPC). Instead of conductor tracks 13, 15, the connection element 4 can also have other conductors. In the present case, contact fingers 6 are arranged on both sides of all piezoelectric elements 3, with the exception of the piezoelectric elements 3 arranged at the longitudinal ends of the device 1. These piezoelectric elements 3 are each connected to each of the contact fingers 6 by a connecting structure 10 in the form of a bonding wire 11. In this way, a redundant contact is created, so that the reliability of the piezoelectric elements 3 is increased. The piezoelectric elements 3 located at the longitudinal ends are each connected to the connection element 4 by only one bonding wire 11. Alternatively, it is also possible that all piezoelectric elements 3 are each connected to only oneBonding wire 11 is connected to the connection element 4. For example, a contact finger 6 can then only be arranged between every second pair of adjacent piezoelectric elements 3. The electrodes 8, 9 can completely cover the top and bottom of the respective piezoelectric element 3 or can also be applied only to parts of the respective sides. The top side is the side of the piezoelectric element 3 facing away from the carrier 2, and the bottom side is the side of the piezoelectric element 3 facing the carrier 2. Figures 2A and 2B show an arrangement of carrier 2 and piezoelectric elements 3 for the device 1 from Figure 1A in a perspective detailed view and a sectional view. The carrier 2 has a T-shaped cross-section. The carrier 2 has a first region 17, which forms a horizontal line of the T-shape, and a second region 18, which forms a vertical line of the T-shape. The first region 17 is designed as a bar with aWidth b1, and the second region 18 is formed as a bar with a width b2 that is less than the width b1. The length l is significantly greater than the widths b1 und b 2 .The piezoelectric elements 3 are attached to a side of the first region 17 that faces away from the second region 18. The piezoelectric elements 3 are arranged in the form of a row with regular spacing on the carrier 2. The piezoelectric elements 3 are attached to the carrier 2 by a fastening material 19, such as a solder connection or an adhesive connection. In addition to the mechanical fastening, the fastening material 19 can also ensure electrical contact between the piezoelectric element 3 and the carrier 2. In particular, the first electrode 8 can be electrically connected to the carrier 2 via the fastening material 19. As described for Figures 1A to 1C, both electrodes 8, 9 can be contacted via the connection element 4.It is also possible for only the second electrode 9 to be contacted via the connection element 4, and for the first electrode 8 to be contacted via another connection or to be at ground potential by grounding the carrier 2. The electrodes 8, 9 can be produced using thin-film or thick-film technology. For example, they involve metallization, for example with a silver paste in a thick-film process. The carrier 2 can comprise a conductive material or consist of a conductive material. For example, it can be aluminum, steel, or titanium. To improve solderability, a coating can be provided for a solder connection. The carrier 2 can also comprise a non-conductive material such as plastic, glass, ceramic, or a glass-reinforced plastic as its base material. P2024,0090 WO N 30.January 2025 - 32 - In the case of a carrier 2 made of a non-conductive base material, electrical contact with the first electrode 8 and / or the second electrodes 9 can be achieved by applied conductor tracks. For example, conductor tracks are applied using a coating process. The piezoelectric elements 3 comprise, for example, a ceramic. This can be a lead-containing ceramic, such as PZT, or a lead-free ceramic. Alternatively, the piezoelectric elements 3 can comprise a polymer as the piezoelectric material. However, the carrier 2 can also be designed differently than shown here, for example as shown in Figures 12, 13, or 14. For example, the carrier 2 can also be formed integrally with a touch element, and it can also not have a T-shaped cross-section. Figure 3A shows a further embodiment of the device 1.In contrast to the device 1 from Figure 1A, the connection element 4 extends only over a short distance along the longitudinal direction L. In particular, the connection element 4 extends over less than half of the longitudinal direction, in particular less than one-fifth of the longitudinal direction. The connection element 4 has only two contact fingers 6, which are fastened to the carrier 2 between piezoelectric elements 3. Thus, only three of the piezoelectric elements 3 are contacted via a connecting structure 10 in the form of bonding wires 11, which are attached to a contact surface 12 of the connection element 4. P2024,0090 WO N January 30, 2025 - 33 - The piezoelectric elements 3, to which no contact finger 6 is directly adjacent, are electrically connected to the connection element 4 via recontacts. In this case, contact with the connection element 4 is established at least via another piezoelectric element 3.Figures 3B and 3C show in detail a contact reversal structure 20 in the form of bonding wires 11 and a contact reversal area 21. Between two adjacent piezoelectric elements 3, a contact reversal area 21 is provided on the carrier 2 for contact reversal of the second electrode 9 of the piezoelectric element 3, which is not directly adjacent to a contact area 12 of the connection element 4. The second electrode 9 of the respective piezoelectric element 3 (see left in Figure 3B) is electrically connected to the contact reversal area 21 by a contact reversal structure 20 in the form of a bonding wire 11. One end of the bonding wire 11 is connected directly to the second electrode 9 and the other end is connected directly to the contact reversal area 21. Another bonding wire 11 connects the contact reversal area 21 to another piezoelectric element 3 (right in Figure 3B).The further piezoelectric element 3 is either connected to a contact surface 21 via a contact structure 20 or to a contact surface 12 of the connection element 4 via a connecting element 11. The contact surface 21 is electrically insulated from the carrier 2. As shown in Figure 3B, the contact surface 21 has a first, uppermost layer 32 that is electrically conductive. P2024,0090 WO N January 30, 2025 - 34 - This can be a metallic layer. The bonding wires 11 are attached to the uppermost layer 32. In addition, the contact surface 21 has a middle layer 33 that is electrically insulating. The contact surface 21 has a lowermost layer 34 that establishes the connection to the base material of the carrier 2. For example, it is an adhesive layer.The insulating layer 33 electrically insulates the carrier 2, which is electrically connected to the first electrode 8, from the contact surface 21, which is electrically connected to the second electrode 9. If the base material of the carrier 2 is non-conductive, the electrically insulating layer 33 is not required. Thus, all piezoelectric elements 3 that are not adjacent to a contact surface 12 are connected to the connection element 4 via a contact structure 20 comprising one or more bonding wires 11, one or more contact surfaces 21, and one or more further piezoelectric elements 3. The embodiment shown here has the advantage that the connection element 4 is only guided along a short section of the carrier 2 and thus contributes less to damping. Furthermore, a short connection element 4 is more cost-effective. In addition, the connection element 4 is only attached to the carrier 2 at a few points, thus simplifying the process.The placement of contact surfaces 21 and the use of bond wires 11 as contact structure 20 has advantages analogous to the placement of contact surfaces 12 and connection structure 10 in Figure 1A. Thus, the contact surfaces 21 are arranged between piezoelectric elements 3 and close to the neutral fibers of the device 1. Due to the extension of the bond wires 11 in the longitudinal direction L, vibration damping is kept to a minimum. The contact structure 20 formed as bond wires 11 can be designed and secured in a manner corresponding to the connection structure 10 formed as bond wires 11. In principle, it is also possible to use connecting elements other than bond wires 11 for the connection structure 10. The arrangement and geometry of the connection element 4 is not limited to the embodiments shown.In particular, different configurations are conceivable, each of which can be optimized for the target application, overall system performance, and / or service life. For example, the connection element 4 can also be led out on the other side of the system, so that the web 5 runs along the side of the contact surfaces 12. Furthermore, it is also possible to lead the connection element 4 out on the front side of the device 1. In this case, the web 5 can also run above piezoelectric elements 3 on the front side. Figure 4A shows a further embodiment of a device 1 for generating a haptic signal. Here, too, as in the embodiment of Figure 3A, re-contacting of piezoelectric elements 3 that are not directly adjacent to a contact surface 12 of a connection element 4 is performed. P2024,0090 WO N 30.January 2025 - 36 - In contrast to the embodiment of Figure 3A, the re-contacting and connection to the connecting element 4 is not performed using bonding wires, but rather using conductive regions 20 and insulating regions 23 on an upper side of the carrier 2. Figure 4B shows a detailed view of the re-contacting and the connection to the connecting element 4; for clarity, the two piezoelectric elements 3, which are arranged closest to the end face of the carrier 2, on which the connecting element 4 is also arranged, are not shown. Thus, the device 1 for connecting to the connecting element 4 has a connection structure 10 in the form of a conductive region 22 on the carrier 2. The conductive region 22 extends in the longitudinal direction L of the carrier 2.The conductive region 22 extends beneath two piezoelectric elements 3 (see Figure 4A) and extends in the longitudinal direction L beyond the piezoelectric elements 3. The piezoelectric elements 3 extend in the width direction beyond the conductive region 22. The configuration of the electrodes 8, 9 of the respective piezoelectric elements 3 of this embodiment is shown in Figures 5A and 5B, wherein Figure 5A shows a view of the underside of the piezoelectric element 3 and Figure 5B shows a view of the top side. To contact the second electrode 9, which is arranged on the top side of the piezoelectric element 3, the second electrode 9 is guided to the underside. In particular, the second electrode 9 is guided over both long sides to the underside. At the bottom, the second electrode 9 is separated from the first electrode by an insulating region 25.The piezoelectric elements 3 are placed with one of the partial regions 26, 27 on a conductive region 22 and connected to it. With the exception of the piezoelectric elements 3 arranged on opposite end faces, the piezoelectric elements 3 are placed with the other of the partial regions 26, 27 on an adjacent conductive region 22 and connected to it. The piezoelectric elements 3, which are adjacent to a contact finger 6 used to contact the second electrode 9, are connected to a conductive region 22 formed as a connecting structure 10. The contact surface 12 of the connection element 4, intended for contacting the second electrode 9, is arranged on the connecting structure 10 formed as a conductive region 22 and fastened to it.The additional piezoelectric elements 3, which are not adjacent to a contact finger 6 used to contact the second electrode 9, are placed on the conductive regions 22 formed as contact structures 20 and are connected to the latter. The first electrode 8 is attached to a further conductive region 24 of the carrier 2 and is electrically connected thereto. The attachment and electrical connection of the partial regions 26, 27 of the second electrode 9 and the first electrode 8 to the conductive regions 22, 24 can be achieved, for example, by soldering or by means of a conductive adhesive. The attachment can be carried out in a common process step. Thus, in this embodiment, both polarities are contacted on an underside of the piezoelectric element 3.A further difference from the previous embodiments is that the contact surface 12 of the connection element 4 for contacting the second electrode 9 is arranged on an underside of the contact finger 6. The connection of the contact surface 12 to the connection structure 10 is made, for example, by soldering or by means of a conductive adhesive. The first electrode 8 is contacted via the further conductive region 24 with a further contact surface 14 of the connection element 4. In contrast to the previous embodiments, the further contact surface 14 is arranged on a different contact finger 6 than the contact surface 12 of the other polarity. The contact surface 14 faces the further conductive region 24 and can be attached to the further conductive region 24, for example, by soldering or by means of a conductive adhesive. The carrier 2 has, for example, a non-conductive base material.In this case, the conductive regions 22, 24 can be applied to the carrier 2 as coatings. It is also possible for the carrier 2 to have a conductive base material. In this case, at least one of the electrically conductive regions 22, 24 is electrically insulated from the carrier material by an electrically non-conductive layer lying underneath. The embodiment shown here has the advantage that fewer elements are required for the contacting. In particular, no bonding wires are required in addition to contact surfaces 12 or contact surfaces 21. Furthermore, the connection element 4 is attached to the respective contact surface 12, 14 only at the respective conductive region 22, 24 and is not contacted at the bottom and top. This can facilitate process control and increase the stability of the attachment.In this embodiment too, the materials and geometries, apart from the details of the connection to the connection element 4 and the re-contacting, can be designed as in the previous embodiments. It is also possible to provide other geometries for the conductive regions 22. For example, with a corresponding design of the electrodes 8, 9, a continuous conductor track can be provided instead of the individual conductive regions 22. Here, too, it is possible to contact the first electrode 8 not via the connection element 4, but via another connection of the carrier 2 and / or a grounding of the carrier 2. In this case, only one contact finger 6 is required. Furthermore, it is also possible to provide several contact fingers 6 for contacting the second electrode 9, for example as in the embodiments of Figures 1A and 3A.Here, too, the connection element 4 can extend over the entire or almost the entire length of the carrier 2 P2024,0090 WO N January 30, 2025 - 40 - . The arrangement and geometry of the connection element 4 is not limited to the embodiment shown here. Furthermore, it is also possible to combine the embodiment according to Figure 3A with the embodiment according to Figure 4A. For example, the re-contacting can be carried out using bonding wires 11 and re-contact areas 21 according to Figure 3A, and the connection to the connection element 4 can be made as in Figure 4A. Likewise, the re-contacting can be carried out using electrically conductive regions 22 according to Figure 4A, and the connection to the connection element 4 can be carried out using bonding wires 11 according to Figure 3A. Figure 6 shows a further embodiment of a device 1.As in the embodiments of Figures 3A to 4B, the connection element 4 extends only over a short distance along the longitudinal direction of the carrier 2 and only along a few of the piezoelectric elements 3. The connection element 4 here runs above the carrier 2 and above two piezoelectric elements 3. The connection element 4 has a contact finger 6 that is directly attached to a piezoelectric element 3. The connection element 4 can have a structure as in Figure 1C, so that it has an upper contact surface 12 and a lower contact surface 14. In the present case, a bonding wire 11 is attached to the upper contact surface 12, which, as part of a contact structure 20, connects more distant piezoelectric elements 3 to the connection element 4 via contact surfaces 21 and further bonding wires 11. The lower contact surface 14 can be directly connected to a second P2024,0090 WO N 30.January 2025 - 41 - Electrode 9 can be contacted on the top side of the piezoelectric element 3, to which the connection element 4 is fastened. Furthermore, the connection element 4 is also designed to contact the first electrodes 8. The connection element 4 has two further contact surfaces 14, which are fastened directly to the carrier 2 and are contacted with the first electrodes 8. The fastening can also be designed here corresponding to the other embodiments. The connection element 4 extends from the front side of the device 1 only along a few piezoelectric elements 3. Thus, the damping can be kept low here too. Figure 7 shows a further embodiment of a device 1, which is designed similarly to the embodiment according to Figure 3A, wherein here the contact structure 20 with bonding wires 11 and contact surfaces 21 is arranged alternately in the region of one long side and in the region of an opposite long side.In this way, the mechanical coupling of the contact structure 20 to the carrier 2 is distributed more evenly over a main surface of the carrier 2, so that no one-sided loading occurs and the overall signal attenuation is reduced. Figure 8 shows a further embodiment of a device 1, wherein two connection elements 4a, 4b are provided here. The connection elements 4a, 4b are designed to connect P2024,0090 WO N January 30, 2025 - 42 - of the same polarity, in particular second electrodes 9. The connection elements 4a, 4b each have contact fingers 6, which each extend from a web 5 between adjacent piezoelectric elements 3. The webs 5 run along opposite longitudinal sides of the device 1. The connection elements 4a, 4b are brought to the piezoelectric elements 3 from different end faces.The connection of the second electrodes 9 to the connection elements 4a, 4b is implemented via bonding wires 11, as in the embodiment of Figure 1A. Along a longitudinal direction L of the device 1, a contact finger 6 of the first connection element 4a and a contact finger 6 of the second connection element 4b extend alternately between piezoelectric elements 3. Furthermore, the bonding wires 11 are arranged alternately in the region of opposite longitudinal sides. The bonding wires 11 and contact fingers 6 are thus distributed as evenly as possible across the device 1. This reduces the mechanical coupling of the respective connection elements 4a, 4b to the carrier 2 and decreases the attenuation. By extending the connection elements 4a, 4b to different end faces, further contacting in the device can be simplified and made more flexible. This embodiment can also be combined, for example, with the re-contacting of Figures 4A and 4B.Figure 9 shows a further embodiment of a device 1, in which two connection elements 4a, 4b are also present for contacting the same polarity. P2024,0090 WO N January 30, 2025 - 43 - In contrast to the embodiment of Figure 7, the connection elements 4a, 4b each extend only a short distance along the longitudinal direction L. The further piezoelectric elements 3 are electrically connected to the connection elements 4a, 4b by means of a re-contact, as shown in Figures 3A or 4A (not shown in detail here). Figures 10 and 11 each show a further embodiment of a device 1, wherein here a connection element 4 has two contact arms 35a, 35b. The contact arms 35a, 35b run along opposite longitudinal sides of the carrier 2 and each have a contact finger 6 that extends between or next to adjacent piezoelectric elements 3.The contact arms 35a, 35b form a plurality of webs 5 of the connection element 4. In Figure 10, the contact fingers 6 are arranged on one end face of the carrier 2. In Figure 11, the contact arms 35a, 35b extend longer along the longitudinal side. In both embodiments, bonding wires 11 can be arranged on different longitudinal sides. Re-contacting of more distant piezoelectric elements 3 can be carried out, for example, using the options shown in Figures 3A or 4A. Figure 12 shows an embodiment of a device 28 for haptic interaction with a user. The device 28 has a device 1 with a carrier 2, piezoelectric elements 3, and a connection element 4. The device 1 is designed, for example, according to one of the previously described embodiments. P2024,0090 WO N January 30, 2025 - 44 - The device 28 has a touch element 29 for interaction with a user.The touch element 29 serves as an output element for the haptic signal. The touch element 29 is designed, for example, in the form of a touch-sensitive screen. The touch element 29 has a surface 30 that can be touched by a user, for example, with a finger or a stylus, and transmits a haptic signal to the user. The device 1 is attached to a rear side of the input element 29, which is facing away from the surface 30. In particular, the second region 18 of the carrier 2 is attached to the rear side 31. The carrier 2 is designed to transmit vibrations to the touch element 29 when the carrier 2 is excited to vibrate by the piezoelectric elements 3. The vibration transmitted to the touch element 29 generates a standing surface wave on the surface 30 of the touch element 29.A user touching the surface 30 of the touch element 29 feels a modulation of the friction generated by the standing wave, and thus a haptically perceptible signal. In particular, the standing wave can generate a deformation of the surface 30 with an amplitude in the micrometer range. The piezoelectric elements 3 can also be designed as sensors and detect pressure on the touch element 29. The haptic perceptible signal can then represent feedback to the application of pressure. P2024,0090 WO N January 30, 2025 - 45 - The device 1 is attached to the touch element 29, for example, using an adhesive or a solder connection. The piezoelectric elements 3 can also be attached to the carrier 2 using an adhesive or a solder connection.The device 28 thus has a first joint between the carrier 2 and piezoelectric elements 3 and a second joint between the contact element 29 and the carrier 2. The thermomechanical properties of the elements involved play a major role in the stability of the joints and the service life of the device 28. In particular, it is advantageous to adapt the thermal expansion coefficients of the elements to be joined in order to prevent premature detachment and / or damage to the elements. The joining agent can also absorb thermomechanical stresses. On the other hand, with sufficient rigidity of the joining agent, lower damping is generated and the signal yield can be increased. In the case of piezoelectric elements 3 comprising a ceramic, adaptation of the thermal expansion coefficients can be achieved by a carrier 2 comprising glass, ceramic, or a glass-reinforced plastic.When a solder is used simultaneously as a joining agent between the piezoelectric elements 3 and the carrier 2, a good signal yield can be achieved due to the rigid connection. By using an adhesive as a joining agent, compensation for mechanical stresses is possible due to the increased material flexibility. However, in this case, the signal yield is reduced compared to a rigid connecting agent. P2024,0090 WO N January 30, 2025 - 46 - In the case of piezoelectric elements 3 comprising a polymer, the piezoelectric elements 3 can compensate for a difference in the expansion coefficients through their own mechanical flexibility. This is not the case with a ceramic material due to the material's brittleness. Thus, with a piezoelectric polymer, the material of the carrier 2 can be selected more freely. Here, too, coupling using a solder material is advantageous for achieving a high signal yield.In the case of piezoelectric elements 3 comprising a composite material, this material can be adapted to the carrier with regard to its properties, in particular the mechanical and / or thermomechanical properties. In particular, the matrix material can be adapted accordingly or consist of similar or identical materials. In general, an adaptation of the mechanical and / or thermomechanical properties of the materials can mean, for example, that the respective characteristic parameters of the materials differ only slightly from one another. For example, the elastic moduli and / or a thermal expansion coefficient differ from one another by a maximum factor of 10, in particular by a maximum factor of 2. In general, soldering as a joining technique combined with materials matched with regard to their thermal expansion coefficients appears to be particularly advantageous in the system composite chain.A material with increased extensibility can also be used as the solder material in order to compensate for stresses due to differences in the thermal expansion coefficients. At the joint between the carrier 2 and the contact element 29, an adaptation of the thermal expansion coefficients can be achieved with a contact element 29 comprising glass or a plastic with a carrier 2 also comprising glass, a plastic, or a glass-reinforced plastic. In the case of a glass-reinforced plastic, the plastic of the contact element 29 can serve as a matrix. The simultaneous use of a solder can ensure optimal signal transmission. Here, too, a compromise must be made between signal yield and the durability of the connection.For example, glass, as a brittle material, can easily break; however, a good match between the expansion coefficients of the contact element 29, the carrier 2, and the ceramic piezoelectric elements 3 can be achieved. Furthermore, the low flexibility allows for high signal yield. By selecting a plastic or glass-reinforced plastic for the contact element 29 and the carrier 2 and a polymer material for the piezoelectric elements 3, a good match between the expansion coefficients can also be achieved, and mechanical stresses can also be compensated. However, greater mechanical flexibility can lead to a lower signal yield. The material combinations proposed here in connection with the device 28 also apply to the device 1. P2024,0090 WO N 30.January 2025 - 48 - Figure 13 shows a further embodiment of a device 28 comprising a device 1 with a carrier 2, piezoelectric elements 3, and connection element 4. In contrast to the embodiment of Figure 13, here the carrier 2 is formed integrally with the touch element 29. Thus, the carrier 2 is formed by the touch element 29. The carrier 2 has, for example, the geometry according to Figures 2A and 2B with a first region 17 and a second region 18. Thus, the device 28 has no joint between the carrier 2 and the input element 28, thereby increasing the stability of the device 28. Figure 14 shows a further embodiment of a device 28 comprising a device 1 with a carrier 2, piezoelectric elements 3 and connection element 4. In contrast to the embodiments of Figures 12 and 13, the carrier 2 does not protrude from a rear side on the contact element 29, but is flush with the rear side.The carrier 2 is formed by the touch element 29. The carrier 2 therefore does not have the structure according to Figures 2A and 2B, but merely a plate-shaped structure of the touch element 29. Otherwise, the device 1 can be designed as described in the previous embodiments. The piezoelectric elements 3 are attached, for example, by means of a conductive adhesive or solder to the carrier 2 designed as a touch element 29. In all embodiments, it is also possible for only one piezoelectric element 3 to be present instead of several piezoelectric elements 3. The piezoelectric elements 3 can also be arranged on several carriers 2. The device 1 can also not have a carrier 2 and can only be attached to a carrier 2 later, for example, directly to the back of a screen.Furthermore, in some embodiments, the one or more piezoelectric elements 3 can have any desired geometric shape. Preferably, the piezoelectric element can have a flat shape. In this context, “flat” means in particular that the piezoelectric element has a significantly smaller spatial extent along a vertical axis than it has extents in a longitudinal and width axes. In particular, the piezoelectric element can be designed as a flat cylinder (“disk”) or as a flat prism (“plate”). In the case of a plate, its base area can be in the shape of a 3-, 4-, 5-, 6-, or n-gon (n is a natural number >6 here). In the case of a disk, its base area can be circular or elliptical. In particular, the piezoelectric element can be designed as a rectangular plate.The piezoelectric elements 3 can each have a monolithic piezoelectric layer. The piezoelectric layer can be arranged between two electrodes 8, 9 arranged on the outer surfaces of the piezoelectric element 3. In particular, the outer electrodes can be arranged on the main surfaces of a flat piezoelectric element 3. The electrodes 8, 9 can be formed, for example, as sputtered electrodes or as single-penetration electrodes. P2024,0090 WO N January 30, 2025 - 50 - For example, the electrodes can be formed as sputtered Cr / Ni / Ag or Cr / Ni / Au electrodes or as Ag, Cu, or Al single-penetration electrodes. A piezoelectric element 3 may comprise a piezoelectric ceramic, for example a lead-containing ceramic such as lead zirconate titanate ceramic (PZT ceramic) or a lead-free ceramic such as bismuth ferrate barium titanate (BFO-BT ceramic).Alternatively, the piezoelectric element 3 can comprise a piezoelectric polymer, for example polyvinylidene fluoride (PVDF). Alternatively, the piezoelectric element 3 can comprise a composite material. For example, a piezoelectric material can be embedded in a matrix material. The matrix material can itself be piezoactive or piezoinactive. In particular, a piezoelectric ceramic material can be embedded in a matrix of piezoelectric plastic. The composite material can also contain further components, for example for adjusting mechanical or thermomechanical properties. For example, glass, mineral, or carbon fibers can additionally be present in the composite material. Alternatively, the piezoelectric element 3 can be a multilayer element comprising stacked piezoelectric layers and internal electrodes.The piezoelectric layers can comprise the aforementioned materials or composite materials. In this case, too, electrodes 8, 9 can be arranged on the main surfaces. The electrodes 8, 9 contact the internal electrodes of the same polarity. The piezoelectric elements 3 can also be used as piezoelectric sensors. The piezoelectric elements 3 can be configured to detect a pressure exerted on a touch element 29 connected to the device 1 or a carrier 2. A piezoelectric element 3 used as a sensor can be the same piezoelectric element 3 that is configured as a piezoelectric actuator. The element that acts as a sensor can be the same element that acts as an actuator. In particular, each element can be configured to act as both an actuator and a sensor.The piezoelectric elements 3 can be attached to the carrier 2 by a joining agent. It is also possible for the piezoelectric elements 3 to be deposited directly onto the carrier 2 without a joining agent. The device 1 can have a coating. This coating can be applied to the piezoelectric elements 3, connection elements 4, 4a, 4b, carriers 2, bonding wires 11, and / or other parts. In particular, the coating provides additional protection for the device 1 and / or the contact element 29 and / or the device 28 against unwanted mechanical influences, dust, moisture, corrosion, static charge, leakage currents, and / or short circuits.

[0002] P2024,0090 WO N January 30, 2025 - 52 - Reference numeral 1 Device 2 Carrier 3 Piezoelectric element 4 Connection element 4a First connection element 4b Second connection element 5 Web 6 Contact finger 7 Connection surface 8 First electrode 9 Second electrode 10 Connection structure 11 Bonding wire 12 Contact surface 13 Conductor track 14 Further contact surface 15 Further conductor track 16 Insulating layer 17 First region 18 Second region 19 Fastening material 20 Contact structure 21 Contact surface 22 Conductive region 23 Insulating region 24 Further conductive region 25 Insulating region 26 First partial region 27 Second partial region 28 Device 29 Touch element P2024,0090 WO N January 30, 2025 - 53 - 30 Surface 31 Rear side 32 Top layer 33 Middle layer 34 bottom layer 35a contact arm 35b contact arm L length direction l length b 1Width first area b 2Width second area

Claims

P2024,0090 WO N January 30, 2025 - 54 - Patent claims 1. Device (1) for generating a haptic signal, comprising one or more piezoelectric elements (3) and at least one connection element (4, 4a, 4b) for electrically connecting the piezoelectric element (3).

2. Device (1) according to claim 1, wherein the piezoelectric elements (3) are arranged on a carrier (2).

3. Device (1) according to claim 2, wherein the connection element (4, 4a, 4b) is fastened to the carrier (2) and / or to at least one of the one or more piezoelectric elements (3), wherein the connection element (4, 4a, 4b) is designed as a flexible printed circuit board.

4. Device (1) according to one of the preceding claims, comprising a plurality of piezoelectric elements (3). 5.Device (1) according to one of claims 2 to 4, wherein the carrier (2) is designed for attachment to a touch element (29) of a haptic device (28), wherein the touch element (29) is designed to output the haptic signal to a user.

6. Device (1) according to one of claims 2 to 5, wherein the carrier (2) is formed by a touch element (29) or an element of a haptic device (28) coupled to a touch element (29), wherein the touch element (29) is designed to output the haptic signal to a user. P2024,0090 WO N January 30, 2025 - 55 - 7. Device (1) according to one of claims 2 to 6, wherein the connection element (4, 4a, 4b) is fastened to the carrier (2).

8. Device (1) according to one of claims 2 to 7, wherein the connection element (4, 4a, 4b) is fastened to the piezoelectric elements (3).

9. Device (1) according to one of the preceding claims, comprising a carrier (2) to which the one or more piezoelectric elements (3) are fastened, wherein the connection element (4, 4a, 4b) is fastened to the carrier (2) next to a piezoelectric element (3) and / or between two adjacent piezoelectric elements (3) in a plan view of a main surface of the carrier (2).Device (1) according to one of the preceding claims, comprising a plurality of piezoelectric elements (3), in which the connection element (4, 4a, 4b) extends along the piezoelectric elements (3) such that the connection element (4) is fastened to and / or next to each piezoelectric element (3).

11. Device (1) according to one of the preceding claims, comprising a plurality of piezoelectric elements (3), in which the connection element (4, 4a, 4b) extends along less than half of the piezoelectric elements (3).

12. Device (1) according to one of the preceding claims, in which the connection element (4, 4a, 4b) is designed as a flexible printed circuit board.

13. Device (1) according to one of the preceding claims. P2024,0090 WO N January 30, 2025 - 56 - wherein the connection element (4, 4a, 4b) has at least one contact finger (6) that is attached to or next to a piezoelectric element (3).

14. The device (1) according to claim 13, wherein the connection element (4, 4a, 4b) has a web (5) from which the contact finger (6) extends.

15. The device (1) according to claim 14, wherein a connection element (4, 4a, 4b) has a plurality of webs (5) that are arranged on different sides of the piezoelectric elements (3).

16. Device (1) according to one of the preceding claims, comprising a carrier (2) to which the one or more piezoelectric elements (3) are attached, wherein the piezoelectric elements (3) each have a first electrode (8) facing the carrier (2) and a second electrode (9) facing away from the carrier (2), wherein the connection element (4, 4a, 4b) contacts at least the second electrode (9).The device (1) according to claim 16, wherein the second electrode (9) is electrically connected to the connection element (4, 4a, 4b) via a connecting structure (10), wherein the connecting structure (20) extends beyond the piezoelectric element (3) when viewed from above onto a main surface of the carrier (2).

18. The device (1) according to claim 17, wherein the connecting structure (10) is designed as a bonding wire (11). P2024,0090 WO N January 30, 2025 - 57 - 19. The device (1) according to claim 17, wherein the connecting structure (10) is formed as a conductive region (22) on the carrier (2), and the second electrode (9) is guided to the side of the piezoelectric element (3) facing the carrier (2).

20. The device (1) according to claim 17, wherein the connection element (4) is directly connected to at least one second electrode (9) on an upper side of a piezoelectric element (3) and directly connected to at least one first electrode (8) on the carrier.

21. Device (1) according to one of the preceding claims, comprising a plurality of piezoelectric elements (3) and comprising a contact structure (20) for electrically connecting one of the piezoelectric elements (3) to the connection element (4, 4a, 4b) via at least one further one of the piezoelectric elements (3). 22.Device (1) according to claim 21, wherein the contact structure (20) has two bonding wires (11) and a contact surface (21).

23. Device (1) according to claim 21, wherein the contact structure (20) has a conductive region (22) onto which two adjacent piezoelectric elements (3) are placed.

24. Device (1) according to one of the preceding claims, wherein the connection element (4, 4a, 4b) comprises both a first electrode (8) of a piezoelectric element (3) and a second electrode (9) of the piezoelectric element (3). P2024,0090 WO N January 30, 2025 - 58 - contacted, wherein the connection element (4) has a contact surface (12) for contacting the second electrode (9) on an upper side and a further contact surface (14) for contacting the first electrode (8) on an underside.

25. Device (1) according to one of the preceding claims, wherein the connection element (4, 4a, 4b) has at least one contact finger (6) which contacts both a first polarity and a second polarity of the one or more piezoelectric elements (3).

26. Device (1) according to one of claims 1 to 24, wherein the connecting element (4, 4a, 4b) has a plurality of contact fingers (6), wherein a first of the contact fingers (6) contacts only a first polarity of the one or more piezoelectric elements (3) and a second of the contact fingers (6) contacts only a second polarity of the one or more piezoelectric elements (3). 27.Device (1) according to one of claims 1 to 23, wherein the connection element (4, 4a, 4b) contacts only one polarity of the one or more piezoelectric elements (3).

28. Device (1) according to one of the preceding claims, comprising at least two connection elements (4, 4a, 4b), wherein both connection elements (4, 4a, 4b) contact the same polarity of the one or more piezoelectric elements (3).

29. Device (1) according to one of the preceding claims, comprising a carrier (2) to which the one or more piezoelectric elements (3) are fastened, wherein the. P2024,0090 WO N January 30, 2025 - 59 - The material of the carrier (2) and the material of the piezoelectric elements (3) are adapted with regard to the mechanical and / or thermomechanical properties.

30. Device (1) according to one of the preceding claims, comprising a carrier (2) to which the one or more piezoelectric elements (3) are fastened, wherein the piezoelectric elements (3) comprise a composite material, wherein the composite material comprises a matrix material and a further material embedded therein, wherein the carrier (2) comprises a corresponding matrix material.

31. Device (1) according to one of the preceding claims, comprising a carrier (2), wherein the one or more piezoelectric elements (3) are deposited on the carrier (2).

32. Device (1) according to one of claims 1 to 29, comprising a carrier (2), wherein the one or more piezoelectric elements (3) are attached to the carrier (2) by a joining means. 33.A device for outputting a haptic signal, comprising the device (1) according to any one of the preceding claims and a surface (30) for interaction with a user, wherein the device (1) is configured to generate a haptic signal via the surface (30).

34. A device according to claim 32, comprising a touch element (29) for interaction with a user, wherein the touch element (29) has the surface (30), wherein the carrier (2) is arranged on the touch element (29). P2024,0090 WO N January 30, 2025 - 60 - 35. Device (28) according to one of claims 33 or 34, comprising a carrier (2) on which the one or more piezoelectric elements (3) are arranged, wherein the carrier (2) is arranged on a touch element (29) or another element of the device (28), wherein the material of the carrier (2) is adapted to the material of the touch element (29) or the other element with regard to the mechanical and / or thermomechanical properties.

36. Device according to one of claims 33 to 35, wherein the carrier (2) is arranged on the touch element (29) or another element of the device (28), wherein the carrier (2) comprises an aluminum, glass, or plastic material and the touch element (29) or the other element comprises a corresponding material.

37. Device according to one of claims 33 to 35, wherein the carrier (2) is deposited on the contact element (29) or another element of the device (28).Device according to one of claims 33 to 35, wherein the carrier (2) is attached to the touch element (29) or another element of the device (28) by a joining means.

39. Device according to claim 33, comprising a touch element (29) for interaction with a user, wherein the touch element (29) has the surface (30), wherein the carrier (2) is formed by the touch element (29).

40. Device according to claim 39. P2024,0090 WO N January 30, 2025 - 61 - wherein the carrier (2) protrudes on a remaining rear side (31) of the touch element (29).

41. Device according to claim 39, wherein the carrier (2) is formed flush with a remaining rear side (31) of the touch element (29).

42. Method for producing the device (1) and / or the device (28) according to one of the preceding claims, wherein the one or more piezoelectric elements (3) are electrically connected to the connection element (4, 4a, 4b).

43. Method according to claim 42, wherein a carrier (2) is provided, wherein the one or more piezoelectric elements (3) are arranged on the carrier (2) and the connection element (4, 4a, 4b) is fastened to the carrier (2).

44. The method according to claim 43, wherein at least one of the piezoelectric elements (3) is electrically connected to the connection element (4, 4a, 4b) by bonding a bonding wire (11). 45.Method according to claim 43, wherein at least one of the piezoelectric elements (3) is electrically connected to the connection element (4, 4a, 4b) via a conductive region (22) on the carrier (2).

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