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

Abstract

Device (28) for outputting a haptic signal, comprising a device (1) for generating a haptic signal and a surface (30) for interaction with a user, wherein the device (1) is configured to generate a haptic signal via the surface (30), wherein the device (1) comprises several piezoelectric elements (3) and at least one connection element (4, 4a, 4b) for electrical connection of the piezoelectric elements (3), wherein the piezoelectric elements (3) are arranged side by side, wherein the connecting element (4, 4a, 4b) has a bridge (5) extending along the multiple piezoelectric elements (4, 4a, 4b) and has multiple contact fingers (6) extending from the bridge (5) into an area next to, between or onto the piezoelectric elements (4, 4a, 4b).

Description

[0001] The present invention relates to a device for generating a haptic signal. In particular, the device can be used with a touch-sensitive display to generate a haptically perceptible signal for a user upon touch.

[0002] 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 substrate, and a mechanical resonant vibration of the substrate 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 the front of the screen, thereby producing a haptically perceptible signal for the user.

[0003] Such devices require a high mechanical displacement. The mechanical fastening and electrical contacting of the piezoelectric elements are crucial for the device's performance. US 2022 / 0066557 A1 describes attaching the piezoelectric elements to the substrate using a conductive adhesive. WO 2022 / 171492 A1 describes attaching the piezoelectric elements using a solder joint, which produces less mechanical damping of the vibration than an adhesive bond, thus enabling improved performance.

[0004] Other piezoelectric transducers are described in DE 102021129229 B9, DE 102013201928 A1, DE 10126656 A1, DE 19928178 A1, DE 102010054589 A1 and DE 10348836 B3.

[0005] An object of the present invention is to provide a device comprising a mechanism for generating a haptic signal with improved properties. For example, the electrical contact of the piezoelectric elements can be improved. The scope of protection is defined by the subject matter of the independent claims. The further claims describe advantageous embodiments.

[0006] According to a first aspect, a device for outputting a haptic signal includes a device for generating a haptic signal, which comprises several piezoelectric elements. The device includes at least one connection element for electrically connecting the piezoelectric elements. The device has a surface for interaction with a user, wherein the device for generating a haptic signal is formed via the surface.

[0007] For example, the piezoelectric elements are arranged in a single row. Other arrangements are also possible. According to the invention, the device does not have only a single piezoelectric element. However, all descriptions relating to a single piezoelectric element apply accordingly to a plurality of piezoelectric elements and vice versa.

[0008] The piezoelectric element can have any 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 along a longitudinal and transverse axis.

[0009] The piezoelectric element can have a monolithic piezoelectric layer. The piezoelectric layer can be arranged between two electrodes located on the outer surfaces of the piezoelectric element. In particular, the outer electrodes can be located on the main surfaces of a flat piezoelectric element. The piezoelectric element can also be designed as a multilayer element, which has stacked piezoelectric layers and inner electrodes.

[0010] The piezoelectric element can be made of 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 can be made of a piezoelectric polymer, for example, polyvinylidene fluoride (PVDF). Alternatively, the piezoelectric element can be made of a composite material.

[0011] The device may have a support. The piezoelectric element may be arranged on the support, in particular attached to the support. The piezoelectric element may be fixed to the support, for example by means of an adhesive. It is also possible that the piezoelectric element is deposited onto the support. The term "fixed" shall also include "deposition" in the following.

[0012] The device can have one or more supports. At least one piezoelectric element can be attached to each support. The device can have any number of supports, on which any number of piezoelectric elements can be attached. For example, a plurality of piezoelectric elements can be attached to one, and in particular a single, support.

[0013] The carrier can be designed to be arranged, in particular attached, to a contact element or another element of a device. The carrier can, for example, be attached by means of an adhesive or deposited onto the element. Here too, the term "attachment" is intended to include deposition.

[0014] A touch element is designed to be touched by a user directly or indirectly, for example, via a stylus. The haptic signal generated by the device is transmitted to the user via a surface of the touch element. For example, the touch element could be a screen, particularly a touch-sensitive screen. The touch element can also be designed as an input element that can be used for input and provides haptic feedback. The carrier is attached, for example, to the back of the touch element. The piezoelectric element can be designed, for example, as both an actuator and a sensor for detecting input. It is also possible for the piezoelectric element to function solely as an actuator.

[0015] It is also possible that the carrier is formed by the touch element and is thus an integral part of the touch element. The carrier may protrude from the remaining rear surface of the touch element. The carrier may also be flush with the remaining rear surface of the touch element. Alternatively, the carrier may be designed as a separate element of the device, for example, as an intermediate element to transmit the haptic signal to a touch element.

[0016] Integrating the carrier and contact element has the advantage of reducing the number of joints in the device. Such joints are often critical to the device's failure risk due to differing coefficients of thermal expansion of the elements being joined and the mechanical movement involved. A first joint can be the connection between the carrier and the one or more piezoelectric elements. A second joint can be the connection between the contact element and the carrier.

[0017] A joint can be formed using an electrically conductive or non-conductive joining material. In particular, a joint can be formed using an adhesive, solder, welding, friction welding, thermode welding, or bonding agent. For example, a joint can be formed using a conductive adhesive, a non-conductive adhesive, an epoxy adhesive, a hard solder, a soft solder, a leaded solder, or a lead-free solder.

[0018] It is also possible for the piezoelectric elements to be connected to the substrate without any adhesive. In particular, in the case of a piezoelectric element comprising a piezoelectric polymer or a composite material with a polymer as the matrix material, no adhesive may be required to attach the piezoelectric element to the substrate. In this case, the piezoelectric element can be deposited directly onto the substrate during manufacturing from a solution or melt, thus forming a directly bonded piezoelectric element. The piezoelectric element is therefore not formed directly by the substrate material, as in other embodiments, but is deposited onto the substrate material.

[0019] If the piezoelectric elements are arranged directly on the back of a touch element, any adhesive between the piezoelectric element and the touch element can be omitted. Similarly, a substrate can be deposited directly onto a touch element or another element of a device, thus forming a material bond.

[0020] The device can also be designed such that it is initially provided in a carrier-free form and then attached to a device. For example, the device is attached to the back of a touch element or an intermediate element.

[0021] The substrate can be made of an electrically conductive or non-conductive material. For example, the substrate can be a metal, a plastic, a glass, a ceramic, or a (fiber) composite material.

[0022] For example, the support can be made of aluminium, steel, titanium, boron-silicate glass, plexiglass, aluminium oxide, GRP (glass fiber reinforced plastic) or CFRP (carbon fiber reinforced plastic).

[0023] If the carrier is not directly formed by the element in which it is intended to stimulate a haptically perceptible signal, the carrier can be made of a similar or identical material to the element or be adapted to a material of the element with regard to its properties, in particular its mechanical and / or thermomechanical properties. The element could, for example, be a touch element of a haptic device.

[0024] For example, the element may be made of aluminum, glass, or plastic. In this case, it may be advantageous if the support is also made of a similar or identical aluminum, glass, or plastic material. If the element is made of a plastic material, such as Plexiglas, the device may be made of a (fiber) composite material, such as a GRP (glass fiber reinforced plastic) material. In particular, the matrix material for a (fiber) composite material of the support may be a plastic material of the object.

[0025] 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.

[0026] For example, the connecting element can be attached directly to a piezoelectric element and directly to the support. Attaching it to the piezoelectric element allows one polarity to be contacted, while attaching it to the support allows the other polarity to be contacted.

[0027] 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 to connect the same or different polarities. For example, there may be several connection elements designed to connect the same polarity.

[0028] The connection elements can be attached to different positions on the device. Such a division of the connections reduces mechanical damping of the device. Furthermore, mechanical damping can be distributed evenly across the device. In addition, the connection elements can exit the device at various points, for example, on opposite end faces. This allows for flexible further contact arrangement.

[0029] The at least one connection element can be attached to at least one support. In particular, the connection element can be attached only to the support and not to any piezoelectric element. Specifically, in the case of multiple connection elements, all connection elements of the device can be attached only to one support and not to the piezoelectric elements. Attaching the connection element to the support, and in particular only to the support, results in lower vibration damping than attaching it to the piezoelectric elements. Specifically, the connection element can be attached to an area on the support that expands little during vibration. Furthermore, attaching the connection element to the support can increase the reliability of the connection, as the connection is subject to less mechanical stress.

[0030] The one or more piezoelectric elements can, for example, be attached to a main surface of the at least one support. 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.

[0031] The one or more connection elements can be attached next to a piezoelectric element. If a support is present, the connection elements can be attached to the support. In a supportless design, the connection elements can be configured to be attached to a support later. In this context, "next to" means, in particular, that no other piezoelectric element is located between the attached area of ​​the connection element and the piezoelectric area. The one or more connection elements can be attached between two adjacent piezoelectric elements. In this context, "adjacent" means that no other piezoelectric element is located between the piezoelectric elements. In such an arrangement, the connection element can be attached near a neutral fiber that does not change length when the device or the support is deformed.Therefore, such a mounting point is low-damping and reliable.

[0032] It is also possible that at least one connecting element is attached to one or more piezoelectric elements, in particular to a top surface of a piezoelectric element. A top surface is a side facing away from a side of the piezoelectric element that is designed for attachment to a support. Attachment "on" or "to" a piezoelectric element or support means, in particular, that the attachment is located directly on the piezoelectric element or the support.

[0033] A connection element can have an electrical conductor. A connection element can also have electrical insulation. For example, a connection element can have a flexible, insulating substrate and at least one conductor, in particular a conductive track, applied to the substrate. The conductive track can be embedded in an electrically insulating substrate. In particular, a connection element can be in the form of a flexible printed circuit board.

[0034] A terminal element can be designed to connect only one polarity. The other polarity can be connected, for example, via another terminal element or a carrier. Alternatively, a terminal element can be designed to connect both polarities. In this case, a terminal element can have two or more electrical conductors, in particular conductive tracks. It can also have multiple electrical insulation layers. For example, a terminal element can be designed to connect only one polarity but have multiple conductive tracks. In particular, a terminal element can be in the form of a flexible printed circuit board with multiple conductive tracks.

[0035] A connection element can extend over the entire or nearly the entire length of a carrier and / or along all piezoelectric elements. Specifically, a connection element can be mounted next to each piezoelectric element. Alternatively or additionally, a connection element can be mounted directly on each piezoelectric element. A combination of mounting next to and on top of the piezoelectric elements is also possible. This allows for particularly simple mounting of all piezoelectric elements.

[0036] Alternatively, a connection element can extend only 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 intended for attachment to a carrier, especially next to less than half of the piezoelectric elements. Thus, fewer contact points of the connection element on the carrier are present or provided. This has the advantage that the connection element is less expensive. Furthermore, such a connection element contributes less to the attenuation of a haptically perceptible signal.

[0037] According to the invention, the connecting element has a bridge from which several contact fingers extend. The bridge can be arranged next to the carrier or the piezoelectric elements when viewed from above, and can extend in the longitudinal direction of the carrier or the arrangement of the piezoelectric elements.

[0038] The contact fingers extend from the bridge into an area adjacent to or between the piezoelectric elements, or onto the piezoelectric elements themselves. A connecting element can partially or completely cover one or more of the piezoelectric elements when viewed from above. Alternatively, a connecting element can, when viewed from above from above, not cover any of the piezoelectric elements, either partially or completely. The bridge can be arranged, in particular, such that it does not cover the support or is not designed to cover a support. This has the advantage that damping of the vibration, and thus damping of a haptically perceptible signal, by the connecting element can be minimized.

[0039] A connecting element can also have multiple ridges. These ridges can extend, for example, along different sides of the piezoelectric elements or a support. A ridge can have multiple contact fingers. These contact fingers can extend at different points along a ridge into the area between the piezoelectric elements.

[0040] The one or more piezoelectric elements can each have a first electrode facing the support and a second electrode facing away from the support. If the device is still without a support, the electrodes can each be configured to face a support or to face away from it.

[0041] The connecting element contacts at least the second electrode. It is also possible for the connecting element to contact both electrodes. The connecting element can be designed to be directly attached to one or more of the piezoelectric elements. Alternatively, the connecting element can be designed so that it is not directly attached to any of the piezoelectric elements. Thus, contact with the upper, second electrode can be achieved by the connecting element being attached to the support rather than directly to the second electrode.

[0042] A contact finger of the connection element can contact both polarities. The connection element can have several such contact fingers. It is also possible that a first contact finger of the connection element contacts only one polarity, for example, the first electrodes, and a second contact finger contacts only the other polarity, for example, the second electrodes. Furthermore, it is also possible that the connection element contacts only the second electrodes.

[0043] The second electrode can be electrically connected to a terminal element via a connection structure. This connection structure extends, particularly in a top view, beyond the contacted piezoelectric element on a main surface of the support or the arrangement of piezoelectric elements. Specifically, the connection structure can extend longitudinally beyond the piezoelectric element. For example, the connection structure is attached at one end to the second electrode and at the other end to a contact surface of a terminal element.

[0044] In one embodiment, the connection structure includes a bond wire. This can be, in particular, a thick wire. The bond wire can be bonded to the second electrode on the top surface of a piezoelectric element and extend to a contact surface of a terminal element, where it can also be bonded to the top surface. The terminal element can be attached to the carrier on its underside or be designed for attachment to the underside of a carrier.

[0045] Bonding offers the advantage of a reliable and process-safe connection. Since the bond is made on the top side of both the piezoelectric element and the connection element, it can also be visually inspected. Thick-wire bonding is particularly easy to handle due to the stiffness of the bonding wire. The bonding wire can extend lengthwise along the device, minimizing vibration damping.

[0046] In another embodiment, the connection structure has a conductive area on the support. As described above, the support can also be a contact element or another component of a device. To connect the upper, second electrode, the second electrode can be positioned on the underside of the piezoelectric element. The piezoelectric element is placed on the conductive area and electrically connected to it. The connection element is also placed on the conductive area and electrically connected to it.

[0047] The device can further comprise a contact structure for electrically connecting one of the piezoelectric elements to the connection element via at least one other piezoelectric element. This is particularly advantageous if the connection element does not extend along the entire length of the support and / or the arrangement of the piezoelectric elements, and in particular if it is not attached to the support next to each of the piezoelectric elements or designed for attachment to a support.

[0048] According to one embodiment, a circumferential contact structure comprises a bond wire and a circumferential contact surface. In particular, the circumferential contact structure can include a bond wire extending from a piezoelectric element to the circumferential contact surface and a further bond wire extending from the circumferential contact surface to another piezoelectric element. The further piezoelectric element can then be connected to a terminal element or to another circumferential contact structure via a connecting structure. The bond wire for the circumferential contact structure can be configured in the same way as the bond wire for the connecting structure described above.

[0049] According to a further embodiment, a circumferential contact structure has a conductive area on a carrier on which two adjacent piezoelectric elements are mounted. To connect the upper, second electrode, the second electrode is brought to the underside of the piezoelectric element. In particular, one piezoelectric element can be placed on the conductive area and electrically connected to it, and another piezoelectric element can be placed on the same conductive area and connected to it. The second piezoelectric element can then be connected to the terminal element by means of a connection structure or to another circumferential contact structure. The conductive areas can be configured like the conductive areas for the connection structure described above.Such a circumferential contact structure has the advantage that fewer separate parts need to be connected and that forming a conductive area is easier to manage and more cost-effective than a connection using a bond wire.

[0050] It is possible to combine the embodiments described above for the connection structure and the contact structure. For example, in one device, the connection structure may be formed using bond wires and the contact structure using conductive areas. Conversely, in another device, the connection structure may be formed using conductive areas and the contact structure using bond wires. It is also possible for the contact structure and connection structure to be configured accordingly.

[0051] The device for outputting a haptic signal has a surface for interaction with a user and the device for generating a haptic signal on the surface. In particular, this can be a deformation, especially a vibration, of the surface. The device can be configured, in particular, as a touch-sensitive screen.

[0052] The device can have a touch element with a surface, wherein the carrier is attached to the touch element, in particular to a rear 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 that the deformation of the object is transmitted to the touch element.

[0053] Alternatively, the support can be formed by the contact element and thus be an integral part of it. The support can protrude from the back of the contact element. The back of the contact element can also be flat.

[0054] An integrated design of the carrier and contact element has the advantage of reducing the number of joints, particularly those requiring a joining material, within the device. Such joints are often critical to the device's failure risk due to differing coefficients of thermal expansion of the elements being joined and the mechanical movement involved. A joint provides a mechanical and / or electrical coupling between two components. A first joint can be the connection between the carrier and the piezoelectric elements. A second joint can be the connection between the contact element and the carrier. Additional joints may also be present.

[0055] First, second, third, or subsequent joints can be joined using the same or different joining materials. The selection of individual joining materials and the coordination between several joining materials can be based on the mechanical coupling, the (thermo-)mechanical behavior, and / or the long-term durability of the joint.

[0056] It is also possible that the piezoelectric element is deposited on the contact element or another element of the device, so that in this case too, no joining point is present and no joining medium is involved.

[0057] To improve the overall system stability, the materials used to join can be matched to their coefficients of thermal expansion. Furthermore, mechanical stresses can be compensated for by the flexibility of the joining material and / or the components. In particular, the aforementioned properties can be tailored to match the corresponding properties of the parts being joined by the joining agent. This allows for the optimization of the properties of the joined component assembly. However, a compromise between signal yield and the compensation of mechanical stresses is necessary.

[0058] According to a further aspect, a method for manufacturing a device for generating a haptic signal and / or a device incorporating the device is specified. This may, 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.

[0059] In this method, one or more piezoelectric elements are connected to at least one terminal element. A carrier can be provided, and the one or more piezoelectric elements can be arranged, in particular attached, to the carrier. An adhesive is used, for example. It is also possible for the piezoelectric elements to be deposited onto the carrier. As described with regard to the device, the carrier can be a separate element, a contact element, or another element of the device.

[0060] The connection element can be attached to the carrier. For example, at least one of the piezoelectric elements is electrically connected to the connection element by bonding a bond wire. Alternatively, at least one of the piezoelectric elements is electrically connected to the connection element via a conductive area on the carrier. Furthermore, as described for the device, additional piezoelectric elements can be connected to the connection element via a contact loop.

[0061] The present invention comprises several aspects, in particular devices and methods. The features, properties and embodiments described for one aspect shall also apply accordingly to the other aspect.

[0062] Furthermore, the description of the items listed here is not limited to the specific embodiments. Rather, the features of the individual embodiments can be combined with one another – insofar as this is technically feasible.

[0063] The following section provides a more detailed explanation of the items described here, using schematic examples.

[0064] They show: Fig. 1A an embodiment of a device in perspective view, Fig. 1B a detail of the device from Fig. 1A in perspective view, Fig. 1C a detail around a contact point of a connecting element in the device made of Fig. 1A in cross-section, Fig. 2A a carrier with piezoelectric elements in an embodiment of the device in perspective view, Fig. 2B the carrier with piezoelectric elements in the device Fig. 2A in cross-section, Fig. 3A another embodiment of the device in perspective view, Fig. 3B a detail of a re-contact in the device Fig. 3A in perspective view, Fig. 3C a detail of a contact surface in the device made of Fig. 3A in perspective view, Fig. 4A another embodiment of a device in perspective view, Fig. 4B a detail of the device from Fig. 4A in perspective view, Fig. 5A a piezoelectric element for the device made of Fig. 4A in perspective view from below, Fig. 5B a piezoelectric element for the device made of Fig. 4A in perspective view from above, Fig. 6 another embodiment of a device in perspective view, Fig. 7 another embodiment of a device in perspective view, Fig. 8 another embodiment of a device in perspective view, Fig. 9 another embodiment of a device in perspective view, Fig. 10 another embodiment of a device in perspective view, Fig. 11 another embodiment of a device in perspective view, Fig. 12 an embodiment of a device in sectional view, Fig. 13 another embodiment of a device in sectional view, Fig. 14 another embodiment of a device in sectional view.

[0065] Preferably, in the following figures, the same reference numerals refer to functionally or structurally corresponding parts of the different embodiments.

[0066] Fig. Figure 1A shows a device 1 for generating a haptic signal. The device 1 is, for example, designed to deflect a touch-sensitive screen so that a haptic impression is created when touched by a user. The device 1 is, for example, designed to be attached to the back of a screen.

[0067] The device 1 comprises a carrier 2 and a plurality of piezoelectric elements 3 attached to it. The piezoelectric elements 3 are configured to cause the carrier 2 to vibrate when an electrical voltage is applied. For example, this vibration occurs at a frequency in the ultrasonic range. The movement of the piezoelectric elements 3 is transmitted to the carrier 2, causing the carrier 2 to also vibrate in the ultrasonic range.

[0068] The carrier 2 can, for example, be designed to be attached to a touch element, such as a haptic surface, of a haptic device. It is also possible that the carrier 2 is formed directly by a touch element or another element of a haptic device. The carrier 2 can also have a different geometry than shown here. For example, the carrier 2 can extend significantly laterally over the piezoelectric elements 3.

[0069] 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.

[0070] 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 simultaneously be configured as sensors to detect pressure acting on a touch element of a haptic device.

[0071] For the electrical connection of the piezoelectric elements 3, the device 1 has a connection element 4. The connection element 4 is attached to the support 2. The connection element 4 is attached to the support 2 next to, and in particular between, the piezoelectric elements 3. An alternating voltage can be applied to the electrodes 8, 9 to generate an oscillation.

[0072] Thus, the connecting element 4 is not directly attached to the piezoelectric elements 3. Viewed from the support 2, the connecting element 4 does not partially or completely cover any of the piezoelectric elements 3. The connecting element 4 is spaced longitudinally L away from all piezoelectric elements 3.

[0073] 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 subjected to less mechanical stress during vibration than when attached directly to a piezoelectric element 3 or guided by piezoelectric elements 3. Furthermore, the damping effect of the connecting element 4 on the vibration can be minimized.

[0074] At the connection point next to and between the piezoelectric elements 3, less strain occurs. In particular, the connection point is positioned as close as possible to a neutral fiber of the device 1. A neutral fiber is defined as one that does not change in length when the assembly of piezoelectric elements 3 and support 2 is deformed.

[0075] In particular, the attachment can be made as close as possible to a so-called "nodal point." The "nodal point" is a point in the cross-section parallel to the vertical axis of the carrier 2 where no vibration occurs on the surface facing the piezoelectric elements 3. Looking at the device 1 from above, this is specifically a point where the neutral fiber runs along a surface of the carrier 2. By mechanically attaching the device at this point, signal attenuation can be kept low and the service life of the connection maximized.

[0076] In the present embodiment, the connecting element 4 extends in the longitudinal direction L along almost the entire length of the carrier 2. The connecting element 4 does not extend along any single one of the piezoelectric elements 3.

[0077] The connection element 4 has a bridge 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 attached there to the carrier 2. The connection element 4 has a comb-like shape. The connection element 4 has a contact surface 7 for external contact.

[0078] Fig. Figure 1B shows an enlarged view of the contacting of the piezoelectric elements 3 by the connecting element 4. Fig. Figure 1B shows an area around a contact point of the connecting element 4 in cross-section.

[0079] 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 a second polarity. The first electrodes 8 are each arranged on a surface of the piezoelectric element 3 facing the support 2. The second electrode 9 is each arranged on a surface of the piezoelectric element 3 facing away from the support 2.

[0080] The piezoelectric elements 3 are electrically connected to the terminal elements 4 via a connection structure 10 in the form of bond wires 11. Each bond wire 11 is connected at one end to the second electrode 9 and at the other end to the terminal element 4. The bond wires 11 each extend from a piezoelectric element 3 to a directly adjacent contact finger 6.

[0081] In particular, the connecting element 4 has a contact surface 12 in the area of ​​each contact finger 6, to which the bond wire 11 is mechanically and electrically connected. The contact surface 12 is connected to an electrical conductor 13 of the connecting element 4, which leads to the connection surface 7. Thus, the connecting element 4 provides an electrical connection for the second electrodes 9.

[0082] Thus, the second electrode 9 is connected to the connecting 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.

[0083] Bonding offers an advantage over other joining methods, such as soldering or gluing, in that the contact point can be visually inspected, thus facilitating effective quality assurance measures. Furthermore, wire bonding benefits from its high degree of automation and reproducibility. Thick-wire bonding is particularly easy to handle due to the strength of the wire and offers high load-bearing capacity.

[0084] The bond wires 11 extend in the longitudinal direction L of the device 1. The bond wires 11 thus have only a small cross-sectional area for contact with the longitudinal direction L, so that the bond wires 11 cause only minimal damping when the device 1 is stretched in the longitudinal direction L due to vibration. Therefore, a large deflection of the device 1 can be achieved.

[0085] The piezoelectric elements 3 are connected to their first electrodes 8 (see Fig. 2B) is attached to the support 2 by an electrically conductive connection. For example, the first electrode 8 is attached to the support 2 by a conductive adhesive or a solder connection. A solder connection has the advantage that the vibration is only slightly damped due to the high stiffness.

[0086] In the case of an electrically conductive carrier 2, a 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 that the further contact surface 14 is soldered to the carrier 2. The further contact surface 14 can also be designed directly as a fastening element. The further contact surface 14 is electrically connected to a further conductor track 15 of the connection element 4. The further conductor track 15 leads to the connection surface 7. Thus, the connection element 4 also provides an electrical connection for the first electrodes 8.

[0087] 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 support for the conductor tracks 13 and 15.

[0088] The connection element 4 is designed in particular as a flexible printed circuit board (FPC).

[0089] Instead of conductor tracks 13, 15, the connecting element 4 can also have other conductors.

[0090] In this case, contact fingers 6 are arranged on both sides of all piezoelectric elements 3, with the exception of those located at the longitudinal ends of the device 1. Each of these piezoelectric elements 3 is connected to each of the contact fingers 6 by a connection structure 10 in the form of a bond wire 11. This creates a redundant contact, thus increasing the reliability of the piezoelectric elements 3. The piezoelectric elements 3 located at the longitudinal ends are each connected to the terminal element 4 by only one bond wire 11.

[0091] Alternatively, it is also possible that all piezoelectric elements 3 are connected to the terminal element 4 by only one bond wire 11. For example, a contact finger 6 can then only be arranged between every second pair of adjacent piezoelectric elements 3.

[0092] The electrodes 8, 9 can completely cover the top and bottom surfaces of the respective piezoelectric element 3 or be applied only to parts of the respective surfaces. The top surface is defined as the surface facing away from the support 2, and the bottom surface of the piezoelectric element 3 facing the support 2 is defined as the surface.

[0093] The Fig. 2A and Fig. Figure 2B shows an arrangement of support 2 and piezoelectric elements 3 for the device 1. Fig. 1A in a perspective detail view and a section view.

[0094] Beam 2 has a T-shaped cross-section. Beam 2 has a first section 17, which forms a horizontal line of the T-shape, and a second section 18, which forms a vertical line of the T-shape. The first section 17 is designed as a beam with a width b1, and the second section 18 is designed as a beam with a width b2, which is less than the width b1. The length l is significantly greater than the widths b1 and b2.

[0095] The piezoelectric elements 3 are attached to one side of the first region 17, facing away from the second region 18. The piezoelectric elements 3 are arranged in a row at regular intervals on the support 2.

[0096] The piezoelectric elements 3 are attached to the carrier 2 by a fastening material 19, such as a solder joint or an adhesive bond. In addition to mechanical fastening, the fastening material 19 can also provide 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.

[0097] How to the Fig. As described in sections 1A to 1C, both electrodes 8 and 9 can be contacted via the connection element 4. It is also possible that only the second electrode 9 is contacted via the connection element 4 and the first electrode 8 is contacted via another connection or is at earth potential due to the grounding of the carrier 2.

[0098] Electrodes 8 and 9 can be produced using thin-film or thick-film technology. For example, they can be metallized, for instance with a silver paste in a thick-film process.

[0099] The support 2 can be made of or consist of a conductive material. For example, it could be aluminum, steel, or titanium. A coating can be applied to improve solderability in a solder joint. The support 2 can also be made of a non-conductive material such as plastic, glass, ceramic, or glass-reinforced plastic.

[0100] In the case of a carrier 2 made of a non-conductive base material, electrical contact between the first electrode 8 and / or the second electrodes 9 can be achieved by means of applied conductive traces. For example, conductive traces are applied by a coating process.

[0101] The piezoelectric elements 3, for example, incorporate a ceramic material. This can be a lead-containing ceramic, such as PZT, or a lead-free ceramic. Alternatively, the piezoelectric elements 3 can incorporate a polymer as the piezoelectric material.

[0102] However, support 2 can also be designed differently than shown here, for example as in the Fig. 12, Fig. 13 or Fig. Figure 14 shows. For example, the support 2 can also be integrally designed with a contact element and it can also not have a T-shaped cross-section.

[0103] In Fig. 3A shows another embodiment of device 1. In contrast to device 1 from Fig. 1A the connecting element 4 extends only a short distance along the longitudinal direction L.

[0104] In particular, the connection element 4 extends over less than half of the longitudinal direction, specifically less than one-fifth of the longitudinal direction. The connection element 4 has only two contact fingers 6, which are attached to the carrier 2 between piezoelectric elements 3. Thus, only three of the piezoelectric elements 3 are contacted via a connection structure 10 in the form of bond wires 11, which are attached to a contact surface 12 of the connection element 4.

[0105] The piezoelectric elements 3, to which no contact finger 6 is directly adjacent, are electrically connected to the terminal element 4 via contact reversals. A contact to the terminal element 4 is established via at least one further piezoelectric element 3.

[0106] In the Fig. 3B and Fig. 3C shows a re-contact structure 20 in the form of bond wires 11 and a re-contact surface 21 in detail. Between two adjacent piezoelectric elements 3, a re-contact surface 21 is provided on the carrier 2 for re-contacting the second electrode 9 of the piezoelectric element 3, which is not directly adjacent to a contact surface 12 of the connection element 4.

[0107] The second electrode 9 of the piezoelectric element 3 in question (see left in Fig. 3B) is electrically connected to the contact surface 21 by a contact structure 20 in the form of a bond wire 11. One end of the bond wire 11 is directly connected to the second electrode 9 and the other end directly to the contact surface 21. Another bond wire 11 connects the contact surface 21 to another piezoelectric element 3 (right in Fig. 3B). The further piezoelectric element 3 is either connected again via a contact structure 20 to a contact surface 21 or via a connecting element 11 to a contact surface 12 of the connection element 4.

[0108] The contact surface 21 is electrically insulated from the carrier 2. As in Fig. As shown in Figure 3B, the contact surface 21 has a first, uppermost layer 32, which is electrically conductive. This layer can be metallic. The bond wires 11 are attached to the uppermost layer 32. The contact surface 21 also has a middle layer 33, which is electrically insulating. Finally, the contact surface 21 has a bottom layer 34, which establishes the connection with the base material of the carrier 2. This layer could, for example, be an adhesive layer.

[0109] The insulating layer 33 electrically isolates 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 carrier 2 is made of a non-conductive base material, the electrically insulating layer 33 is not required.

[0110] Thus, all piezoelectric elements 3 that are not adjacent to a contact surface 12 are connected to the terminal element 4 via a re-contact structure 20, comprising one or more bond wires 11, one or more re-contact surfaces 21 and one or more further piezoelectric elements 3.

[0111] The embodiment shown here has the advantage that the connecting element 4 is guided only along a short section of the support 2 and therefore contributes less to damping. Furthermore, a short connecting element 4 is more cost-effective. In addition, the connecting element 4 is attached to the support 2 at only a few points, thus simplifying process control.

[0112] The placement of re-contact surfaces 21 and the use of bond wires 11 as re-contact structure 20 has analogous advantages to the placement of contact surfaces 12 and connection structure 10 in Fig. 1A. The contact surfaces 21 are arranged between piezoelectric elements 3 and close to the neutral fibers of the device 1. The longitudinal extension of the bond wires 11 in the direction L minimizes vibration damping. The contact structure 20, designed as bond wires 11, can be configured and attached in a manner corresponding to the connection structure 10, which is also designed as bond wires 11.

[0113] In principle, it is also possible to use other connecting elements than bond wires 11 for the connection structure 10.

[0114] The arrangement and geometry of the connection element 4 are not limited to the embodiments shown. In particular, various configurations are conceivable, each optimized for the target application, overall system performance, and / or service life. For example, the connection element 4 can also be routed out on the other side of the system, so that the web 5 runs along the side of the contact surfaces 12. It is also possible to route the connection element 4 out at the end face of the device 1. In this case, the web 5 can also run above piezoelectric elements 3 on the end face.

[0115] Fig. Figure 4A shows another embodiment of a device 1 for generating a haptic signal. Here too, as in the embodiment above, the following components are used: Fig. 3A a re-contacting of piezoelectric elements 3 was carried out which are not directly adjacent to a contact surface 12 of a connection element 4.

[0116] In contrast to the embodiment made of Fig. 3A the re-contacting and connection with the terminal element 4 is not carried out by means of bond wires, but by means of conductive areas 20 and insulating areas 23 on a top side of the carrier 2.

[0117] In Fig. Figure 4B shows a detailed view of the re-contacting and the connection to the terminal element 4, whereby, for better illustration, the two piezoelectric elements 3, which are located closest to the front face of the carrier 2, on which the terminal element 4 is also located, are not shown.

[0118] Thus, the device 1 for connection with the connecting element 4 has a connection structure 10 in the form of a conductive area 22 on the carrier 2. The conductive area 22 extends in the longitudinal direction L of the carrier 2. The conductive area 22 extends below two piezoelectric elements 3 (see Fig. 4A) and extends longitudinally L beyond the piezoelectric elements 3. The piezoelectric elements 3 extend laterally beyond the conductive area 22.

[0119] The formation of the electrodes 8, 9 of the respective piezoelectric elements 3 of this embodiment is described in the Fig. 5A and Fig. 5B shown, where Fig. 5A a view of the underside of the piezoelectric element 3 and Fig. 5B shows a view of the top.

[0120] To make contact with the second electrode 9, which is located on the top side of the piezoelectric element 3, the second electrode 9 extends to the underside. Specifically, the second electrode 9 extends to the underside along both longitudinal sides. On the underside, the second electrode 9 is separated from the first electrode by an insulating section 25.

[0121] The piezoelectric elements 3 are placed on and connected to a conductive area 22 with one of the sub-areas 26, 27. With the exception of the piezoelectric elements 3 arranged on opposite end faces, the piezoelectric elements 3 are placed on and connected to an adjacent conductive area 22 with the other of the sub-areas 26, 27. The piezoelectric elements 3 adjacent to a contact finger 6, which is used to contact the second electrode 9, are connected to a conductive area 22 designed as a connection structure 10. The contact surface 12 of the connecting element 4, intended for contacting the second electrode 9, is arranged on and attached to the connection structure 10 designed as a conductive area 22.

[0122] The other piezoelectric elements 3, which are not adjacent to a contact finger 6 used to contact the second electrode 9, are placed on and connected to the conductive areas 22 designed as circum-contact structures 20.

[0123] The first electrode 8 is attached to and electrically connected to another conductive area 24 of the carrier 2. The attachment and electrical connection of the sub-areas 26, 27 of the second electrode 9 and the first electrode 8 to the conductive areas 22, 24 can be achieved, for example, by soldering or by using a conductive adhesive. The attachment can be carried out in a single process step.

[0124] Thus, in this embodiment, both polarities are contacted on one underside of the piezoelectric element 3.

[0125] Another difference from the previous embodiments is that the contact surface 12 of the connecting 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 effected, for example, by soldering or by means of a conductive adhesive.

[0126] The first electrode 8 is contacted via the further conductive area 24 with a further contact surface 14 of the connecting 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 opposite polarity. The contact surface 14 faces the further conductive area 24 and can be attached to the further conductive area 24, for example, by soldering or by means of a conductive adhesive.

[0127] For example, the support 2 has a non-conductive base material. In this case, the conductive areas 22, 24 can be applied to the support 2 as coatings. It is also possible that the support 2 has a conductive base material. In this case, at least one of the electrically conductive areas 22, 24 is electrically insulated from the support material by an underlying electrically non-conductive layer.

[0128] The embodiment shown here has the advantage that fewer elements are required for the re-contacting. In particular, no bond wires are needed in addition to contact surfaces 12 or re-contact surfaces 21. Furthermore, the connection element 4 is attached to the respective conductive area 22, 24 of the respective contact surface 12, 14 and is not contacted on the underside and top side. This can simplify process control and increase the stability of the attachment.

[0129] In this embodiment as well, the materials and geometries can be designed as in the previous embodiments, apart from the details of the connection with the connecting element 4 and the re-contacting.

[0130] It is also possible to provide other geometries for the conductive areas 22. For example, with appropriate design of the electrodes 8, 9, a continuous conductor track can be provided instead of the individual conductive areas 22.

[0131] It is also possible here to contact the first electrode 8 not via the connection element 4, but via another connection of the carrier 2 and / or an earth connection of the carrier 2. In this case, only one contact finger 6 is required. Furthermore, it is also possible for several contact fingers 6 to be provided for contacting the second electrode 9, for example as in the embodiments of Fig. 1A and Fig. 3A. Here too, the connecting element 4 can extend over the entire or almost the entire length of the support 2. The arrangement and geometry of the connecting element 4 are also not limited to the embodiment shown.

[0132] Furthermore, it is also possible to design the embodiment according to Fig. 3A with the embodiment according to Fig. 4A to combine. For example, the re-contacting can be carried out using bond wires 11 and re-contact surfaces 21 according to Fig. 3A and the connection with the terminal element 4 as shown in Fig. 4A. Similarly, re-contacting can be carried out using electrically conductive areas 22 according to Fig. 4A and the connection to the terminal element 4 by means of bond wires 11 according to Fig. 3A will be carried out.

[0133] Fig. Figure 6 shows another embodiment of a device 1. As in the embodiments of Fig. In sections 3A to 4B, the connecting element 4 extends only a short distance along the longitudinal direction of the carrier 2 and only along a few of the piezoelectric elements 3.

[0134] The connecting element 4 runs above the support 2 and above two piezoelectric elements 3. The connecting element 4 has a contact finger 6 which is directly attached to a piezoelectric element 3.

[0135] The connecting element 4 can have a structure as shown in Fig. The 1C has an upper contact surface 12 and a lower contact surface 14. In this case, a bond wire 11 is attached to the upper contact surface 12. This bond wire, as part of a recirculating contact structure 20, connects more distant piezoelectric elements 3 to the terminal element 4 via recirculating contact surfaces 21 and further bond wires 11. The lower contact surface 14 can be directly contacted with a second electrode 9 on the top surface of the piezoelectric element 3 to which the terminal element 4 is attached.

[0136] Furthermore, the connecting element 4 is also designed to contact the first electrodes 8. The connecting element 4 has two further contact surfaces 14, which are directly attached to the carrier 2 and are contacted with the first electrodes 8. The attachment can be designed accordingly, as in the other embodiments.

[0137] The connecting element 4 extends from the front face of the device 1 only along a few piezoelectric elements 3. Thus, the damping can also be kept low here.

[0138] Fig. Figure 7 shows a further embodiment of a device 1, which is similar to the embodiment according to Fig. 3A is formed, wherein the re-contact structure 20 with bond wires 11 and re-contact surfaces 21 is arranged alternately in the area of ​​one longitudinal side and in the area of ​​an opposite longitudinal side.

[0139] In this way, the mechanical coupling of the circumferential contact structure 20 with the carrier 2 is distributed more evenly over a main area of ​​the carrier 2, so that no one-sided load occurs and the attenuation of the signal is reduced overall.

[0140] Fig. Figure 8 shows a further embodiment of a device 1, wherein two connection elements 4a, 4b are provided. The connection elements 4a, 4b are designed for connecting the same polarity, in particular second electrodes 9.

[0141] The connecting elements 4a, 4b each have contact fingers 6 extending from a bridge 5 between adjacent piezoelectric elements 3. The bridges 5 run along opposite longitudinal sides of the device 1. The connecting elements 4a, 4b are brought into contact with the piezoelectric elements 3 from different end faces. The connection of the second electrodes 9 to the connecting elements 4a, 4b is as in the embodiment shown. Fig. 1A is carried out via bond wires 11.

[0142] 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 alternately extend between piezoelectric elements 3. In addition, the bond wires 11 are alternately positioned on opposite longitudinal sides. The bond wires 11 and contact fingers 6 are thus distributed as evenly as possible over the device 1. This reduces the mechanical coupling of the respective connection elements 4a, 4b with the carrier 2 and decreases the damping. By extending the connection elements 4a, 4b from different end faces, further contacting within the device can be simplified and made more flexible.

[0143] This embodiment can also be achieved, for example, by re-contacting the Fig. 4A and Fig. 4B can be combined.

[0144] Fig. Figure 9 shows another embodiment of a device 1 in which two connection elements 4a, 4b are also provided for contacting the same polarity.

[0145] The connecting elements 4a, 4b extend in contrast to the embodiment of the Fig. 7 each only over a short distance along the longitudinal direction L. The further piezoelectric elements 3 are connected by means of a re-contacting, as in the Fig. 3A or Fig. 4A shown, electrically connected with connection elements 4a, 4b (not shown in detail here).

[0146] The Fig. 10 and Fig. Figures 11 each show a further embodiment of a device 1, wherein a connecting element 4 has two contact arms 35a, 35b. The contact arms 35a, 35b extend along opposite longitudinal sides of the carrier 2 and each has a contact finger 6 that extends between or alongside adjacent piezoelectric elements 3. The contact arms 35a, 35b form several webs 5 of the connecting element 4.

[0147] In Fig. 10. The contact fingers 6 are arranged on one end face of the carrier 2. In Fig. In embodiment 11, the contact arms 35a, 35b extend further along the longitudinal side. In both embodiments, bond wires 11 can be arranged on different longitudinal sides. For example, re-contacting of more distant piezoelectric elements 3 can be achieved by means of the [missing information - likely a specific feature or feature]. Fig. 3A or Fig. The possibilities shown in 4A can be carried out.

[0148] In Fig. Figure 12 shows an embodiment of a device 28 for haptic interaction with a user. The device 28 comprises a device 1 with a carrier 2, piezoelectric elements 3, and a connection element 4. The device 1 is configured, for example, according to one of the embodiments described above.

[0149] 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, for example, designed 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 which transmits a haptic signal to the user. The device 1 is attached to a rear side of the input element 29 that faces away from the surface 30. In particular, the second area 18 of the carrier 2 is attached to the rear side 31.

[0150] 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 perceives a modulation of friction generated by the standing wave, thus experiencing a haptically perceptible signal. In particular, the standing wave can generate a deformation of the surface 30 with an amplitude in the micrometer range.

[0151] The piezoelectric elements 3 can also be configured as sensors and detect pressure on the touch element 29. The haptically perceptible signal can then represent feedback on a pressure application.

[0152] The device 1 is attached to the contact element 29, for example, by means of an adhesive or a soldered connection. The piezoelectric elements 3 can also be attached to the carrier 2 by means of an adhesive or a soldered connection.

[0153] The device 28 thus has a first joint between carrier 2 and piezoelectric elements 3 and a second joint between contact element 29 and carrier 2. The thermomechanical properties of the elements involved play a significant role in the stability of the joints and the service life of the device 28. In particular, it is advantageous to match the coefficients of thermal expansion of the elements to be joined in order to prevent premature detachment and / or damage to the elements. The joining material can also absorb thermomechanical stresses. Conversely, if the joining material has sufficient stiffness, less damping is generated and the signal yield can be increased.

[0154] In the case of piezoelectric elements 3 comprising a ceramic substrate, the coefficients of thermal expansion can be adjusted by using a substrate 2 comprising glass, ceramic, or a glass-reinforced plastic. When a solder is used as an adhesive between the piezoelectric elements 3 and the substrate 2, a good signal yield can be achieved due to the rigid connection. Using an adhesive as an adhesive allows for compensation of mechanical stresses due to the increased material flexibility. However, in this case, the signal yield is reduced compared to a rigid connection.

[0155] In the case of piezoelectric elements 3 comprising a polymer, the piezoelectric elements 3 can compensate for differences in their coefficients of thermal expansion due to their own mechanical flexibility. This is not the case with a ceramic material due to its brittleness. Therefore, with a piezoelectric polymer, the substrate material 2 can be chosen more freely. Here too, coupling via a solder material is advantageous for achieving a high signal yield.

[0156] In the case of piezoelectric elements 3 comprising a composite material, this material can be adapted to that of the substrate with regard to its properties, in particular its mechanical and / or thermomechanical properties. In particular, the matrix material can be adapted accordingly or consist of similar or identical materials.

[0157] In general, adjusting 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 moduli of elasticity and / or a coefficient of thermal expansion differ from one another by a factor of at most 10, and in particular by a factor of at most 2.

[0158] In general, soldering as a joining technique, combined with materials matched in terms of their coefficients of thermal expansion, appears to be particularly advantageous in the system assembly chain. A material with increased ductility can also be used as the solder material to compensate for stresses resulting from differences in the coefficients of thermal expansion.

[0159] At the joint between carrier 2 and contact element 29, an adjustment of the coefficients of thermal expansion can be achieved for a contact element 29 comprising glass or a plastic, and for 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. Optimal signal transmission can be ensured by simultaneously using a solder.

[0160] Here, too, a compromise must be made between signal yield and connection durability. For example, glass, being a brittle material, can break easily; however, a good match of the expansion coefficients of the contact element 29, carrier 2, and ceramic piezoelectric elements 3 can be achieved. Furthermore, the low flexibility allows for high signal yield. Choosing a plastic or glass-reinforced plastic for the contact element 29 and carrier 2, and a polymer material for the piezoelectric elements 3, also allows for a good match of the expansion coefficients and compensation of mechanical stresses. However, higher mechanical flexibility can lead to lower signal yield.

[0161] The material combinations proposed here in connection with device 28 also apply to device 1.

[0162] Fig. Figure 13 shows a further embodiment of a device 28 comprising a device 1 with carrier 2, piezoelectric elements 3 and connection element 4.

[0163] In contrast to the embodiment made of Fig. In section 13, the support 2 is formed as a single unit with the contact element 29. Thus, the support 2 is formed by the contact element 29. The support 2 has, for example, the geometry according to the Fig. 2A and Fig. 2B with first area 17 and second area 18.

[0164] Thus, the device 28 has no joint between carrier 2 and input element 28, thereby increasing the stability of the device 28.

[0165] Fig. Figure 14 shows a further embodiment of a device 28 comprising a device 1 with a carrier 2, piezoelectric elements 3 and a connection element 4. In contrast to the embodiments of Fig. 12 and Fig. 13. The carrier 2 does not protrude from a rear side of the contact element 29, but is flush with the rear side. The carrier 2 is formed by the contact element 29.

[0166] Carrier 2 therefore does not exhibit the structure according to the Fig. 2A and Fig. 2B, but merely a plate-shaped structure of the contact element 29. Otherwise, the device 1 can be configured as described in the preceding embodiments. The piezoelectric elements 3 are, for example, attached to the carrier 2, which serves as the contact element 29, by means of a conductive adhesive or solder.

[0167] In all embodiments, it is also possible that instead of several piezoelectric elements 3, only one piezoelectric element 3 is present. The piezoelectric elements 3 can also be arranged on several supports 2. The device 1 can also have no support 2 and only be attached to a support 2 later, for example, directly to the back of a screen.

[0168] Furthermore, in individual embodiments, the one or more piezoelectric elements 3 can have any 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 along a longitudinal and transverse axis.

[0169] 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 can be in the form of a 3-, 4-, 5-, 6-, or n-gon (n being a natural number > 6). In the case of a disk, its base can be circular or elliptical. The piezoelectric element can also be designed as a rectangular plate.

[0170] The piezoelectric elements 3 can each have a monolithic piezoelectric layer. The piezoelectric layer can be arranged between two electrodes 8, 9, which are located on the outer surfaces of the piezoelectric element 3. In particular, the outer electrodes can be located on the main surfaces of a flat piezoelectric element 3.

[0171] Electrodes 8 and 9 can be designed, for example, as sputtered electrodes or as burn-in electrodes. For example, the electrodes can be designed as sputtered Cr / Ni / Ag or Cr / Ni / Au electrodes or as Ag, Cu, or Al burn-in electrodes.

[0172] A piezoelectric element 3 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 as bismuth ferrate barium titanate (BFO-BT ceramic). Alternatively, the piezoelectric element 3 can be a piezoelectric polymer, for example, polyvinylidene fluoride (PVDF). Alternatively, the piezoelectric element 3 can be a composite material. For example, a piezoelectric material can be embedded in a matrix material. The matrix material itself can be piezoactive or piezoinactive. In particular, a piezoelectric ceramic material can be embedded in a matrix of piezoelectric polymer. The composite material can also contain other components, for example, for adjusting mechanical or thermomechanical properties.For example, glass, mineral or carbon fibers may also be present in the composite material.

[0173] Alternatively, the piezoelectric element 3 can be a multilayer element comprising stacked piezoelectric layers and inner electrodes. The piezoelectric layers can be made of the aforementioned materials or composite materials. In this case as well, electrodes 8 and 9 can be arranged on the main surfaces. Electrodes 8 and 9 contact the inner electrodes of the same polarity.

[0174] The piezoelectric elements 3 can also be used as piezoelectric sensors. In this context, the piezoelectric elements 3 can be configured to detect pressure exerted on a contact element 29 connected to the device 1 or a support 2. A piezoelectric element 3 used as a sensor can be the same piezoelectric element 3 configured as a piezoelectric actuator. The element acting as a sensor can be the same element acting as an actuator. In particular, each element can be configured to act as both an actuator and a sensor.

[0175] The piezoelectric elements 3 can be attached to the substrate 2 by means of an adhesive. It is also possible that the piezoelectric elements 3 are deposited directly onto the substrate 2 without an adhesive.

[0176] The device 1 may have a coating. This coating may be applied to the piezoelectric elements 3, connection elements 4, 4a, 4b, supports 2, bond wires 11 and / or other parts. In particular, the coating serves to provide additional protection for the device 1 and / or the contact element 29 and / or the device 28 against unwanted mechanical impact, dust, moisture, corrosion, static charge, leakage currents and / or short circuits. Reference sign 1 Device 2 carriers 3 piezoelectric element 4 Connection element 4a first connection element 4b second connection element 5 Bridge 6 contact fingers 7 Connection area 8 first electrode 9 second electrode 10 Connection structure 11 Bond wire 12 Contact area 13 conductor track 14 additional contact surfaces 15 more conductor tracks 16 insulating layer 17 first area 18 second area 19 Fastening material 20 Re-contact structure 21 Contact area 22 conductive area 23 insulating area 24 additional conductive areas 25 insulating area 26 first sub-area 27 second sub-area 28 device 29 Touch element 30 surface 31 Back 32 top layer 33 middle layer 34 bottom layer 35a Contact arm 35b Contact arm L Longitudinal direction l length b1 Width first area b2 Width second area

Claims

[1] Device (28) for outputting a haptic signal, comprising a device (1) for generating a haptic signal and a surface (30) for interacting with a user, wherein the device (1) for generating a haptic signal is configured via the surface (30), wherein the device (1) comprises several piezoelectric elements (3) and at least one connection element (4, 4a, 4b) for electrical connection of the piezoelectric elements (3), wherein the piezoelectric elements (3) are arranged side by side, wherein the connecting element (4, 4a, 4b) has a bridge (5) extending along the multiple piezoelectric elements (4, 4a, 4b) and has multiple contact fingers (6) extending from the bridge (5) into an area next to, between or onto the piezoelectric elements (4, 4a, 4b). [2] Device (28) according to claim 1, wherein the device (1) has a carrier (2) on which the piezoelectric elements (3) are arranged. [3] Device (28) according to claim 2, wherein the carrier (2) is designed for attachment to a touch element (29) of the haptic device (28), wherein the touch element (29) is designed for outputting the haptic signal to a user. [4] Device (28) according to claim 2, wherein the carrier (2) is formed by a touch element (29) or an element of the haptic device (28) coupled to a touch element (29), wherein the touch element (29) is configured to output the haptic signal to a user. [5] Device (28) according to one of claims 2 to 4, wherein the connecting element (4, 4a, 4b) is attached to the carrier (2). [6] Device (28) according to one of the preceding claims, wherein the connecting element (4, 4a, 4b) is attached to the piezoelectric elements (3). [7] Device (28) according to one of the preceding claims, comprising a carrier (2) to which the one or more piezoelectric elements (3) are attached, wherein the connecting element (4, 4a, 4b) is attached to the carrier (2) in view of a main surface of the carrier (2) next to a piezoelectric element (3) and / or between two adjacent piezoelectric elements (3). [8] Device (28) according to one of the preceding claims, wherein the connecting element (4, 4a, 4b) extends along the piezoelectric elements (3) such that the connecting element (4) is attached to and / or next to each piezoelectric element (3). [9] Device (28) according to one of the preceding claims, wherein the connecting element (4, 4a, 4b) extends along less than half of the piezoelectric elements (3). [10] Device (28) according to one of the preceding claims, wherein the connection element (4, 4a, 4b) is designed as a flexible printed circuit board. [11] Device (28) according to one of the preceding claims, wherein a connecting element (4, 4a, 4b) has several webs (5) arranged on different sides of the piezoelectric elements (3). [12] Device (28) according to one of the preceding claims, comprising a carrier (2) to which the multiple 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 connecting element (4, 4a, 4b) contacts at least the second electrode (9). [13] Device (28) according to claim 12, wherein the second electrode (9) is electrically connected to the connection element (4, 4a, 4b) via a connection structure (10), the connection structure (20) extending beyond the piezoelectric element (3) when viewed from above on a main surface of the carrier (2). [14] Device (28) according to claim 13, wherein the connection structure (10) is designed as a bond wire (11). [15] Device (28) according to claim 13, wherein the connection structure (10) is formed as a conductive area (22) on the carrier (2) and the second electrode (9) is guided to the side of the piezoelectric element (3) facing the carrier (2). [16] Device (28) according to claim 13, wherein the connecting element (4) is directly connected to at least one second electrode (9) on a top side of a piezoelectric element (3) and directly connected to at least one first electrode (8) on the support. [17] Device (28) according to one of the preceding claims, 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 of the piezoelectric elements (3). [18] Device (28) according to claim 17, wherein the re-contact structure (20) comprises two bond wires (11) and a re-contact surface (21). [19] Device (28) according to claim 17, wherein the circum-contact structure (20) has a conductive area (22) on which two adjacent piezoelectric elements (3) are mounted. [20] Device (28) according to one of the preceding claims, wherein the connecting 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). [21] Device (28) according to any one of claims 1 to 19, wherein a first contact finger (6) contacts only a first polarity of the piezoelectric elements (3) and a second contact finger (6) contacts only a second polarity of the piezoelectric elements (3). [22] Device (28) according to any one of claims 1 to 19, wherein the connecting element (4, 4a, 4b) contacts only one polarity of the one or more piezoelectric elements (3). [23] Device (28) 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 one or more piezoelectric elements (3). [24] Device (28) according to one of the preceding claims, comprising a carrier (2) to which the multiple piezoelectric elements (3) are attached, wherein the material of the carrier (2) is adapted to the material of the piezoelectric elements (3) with respect to the mechanical and / or thermomechanical properties. [25] Device (28) according to one of the preceding claims, comprising a carrier (2) to which the multiple piezoelectric elements (3) are attached, wherein the piezoelectric elements (3) comprise a composite material, the composite material comprising a matrix material and a further material embedded therein, wherein the carrier (2) comprises a corresponding matrix material. [26] Device (28) according to one of the preceding claims, comprising a carrier (2) wherein the multiple piezoelectric elements (3) are deposited on the carrier (2). [27] Device (28) according to one of claims 1 to 24, comprising a carrier (2), wherein the multiple piezoelectric elements (3) are attached to the carrier (2) by an joining means. [28] Device according to one of the preceding claims, 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). [29] Device (28) according to one of the preceding claims, comprising a carrier (2) on which the one or more piezoelectric elements (3) are arranged, wherein the carrier (2) is arranged on a contact element (29) or another element of the device (28), wherein the material of the carrier (2) is adapted to the material of the contact element (29) or the other element with respect to its mechanical and / or thermomechanical properties. [30] Device (28) according to one of the preceding claims, wherein the carrier (2) is arranged on the touching element (29) or another element of the device (28), wherein the carrier (2) has an aluminium, glass or plastic material and the touching element (29) or the other element has a corresponding material. [31] Device according to one of the preceding claims, wherein the carrier (2) is deposited on the contact element (29) or another element of the device (28). [32] Device according to one of the preceding claims, wherein the carrier (2) is attached to the touching element (29) or to another element of the device (28) by means of an joining means. [33] Device according to any one of claims 1 to 27, comprising a touch element (29) for interaction with a user, wherein the touch element (29) has the surface (30), wherein the support (2) is formed by the touch element (29). [34] Device according to claim 33, wherein the carrier (2) protrudes from a remaining rear side (31) of the touching element (29). [35] Device according to claim 33, wherein the carrier (2) is formed flat with a remaining rear side (31) of the touching element (29). [36] Method for manufacturing the device (28) according to one of the preceding claims, wherein the multiple piezoelectric elements (3) are arranged side by side and electrically connected to the connection element (4, 4a, 4b), the connection element (4, 4a, 4b) having a bridge (5) extending along the multiple piezoelectric elements (4, 4a, 4b) and having multiple contact fingers (6) extending from the bridge (5) into an area next to, between or onto the piezoelectric elements (4, 4a, 4b), the device (28) having a surface (30) for interaction with a user, the device (1) being designed to generate a haptic signal via the surface (30). [37] Method according to claim 36, wherein a carrier (2) is provided, the multiple piezoelectric elements (3) are arranged on the carrier (2) and the connection element (4, 4a, 4b) is attached to the carrier (2). [38] Method according to claim 37, wherein at least one of the piezoelectric elements (3) is electrically connected to the connection element (4, 4a, 4b) by bonding a bond wire (11). [39] Method according to claim 37, wherein at least one of the piezoelectric elements (3) is electrically connected to the connection element (4, 4a, 4b) via a conductive area (22) on the support (2).

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